[ { "id": "authors:2ma17-86y37", "collection": "authors", "collection_id": "2ma17-86y37", "cite_using_url": "https://authors.library.caltech.edu/records/2ma17-86y37", "type": "article", "title": "Spindle-localized F-actin regulates polar MTOC organization and the fidelity of meiotic spindle formation", "author": [ { "family_name": "Soto-Moreno", "given_name": "Edgar J." }, { "family_name": "Ali", "given_name": "Nourhan N." }, { "family_name": "K\u00fcllmer", "given_name": "Florian", "orcid": "0000-0002-0671-1546" }, { "family_name": "Nasufovic", "given_name": "Veselin", "orcid": "0000-0001-6812-637X" }, { "family_name": "Frolikova", "given_name": "Michaela", "orcid": "0000-0002-9834-8405" }, { "family_name": "Tepla", "given_name": "Olga" }, { "family_name": "Masata", "given_name": "Jaromir" }, { "family_name": "Trauner", "given_name": "Dirk", "orcid": "0000-0002-6782-6056" }, { "family_name": "Patterson", "given_name": "Amanda A." }, { "family_name": "Arndt", "given_name": "Hans-Dieter", "orcid": "0000-0002-0792-1422" }, { "family_name": "Komrskova", "given_name": "Katerina", "orcid": "0000-0002-6837-2148" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Balboula", "given_name": "Ahmed Z.", "orcid": "0000-0001-9663-6262" } ], "abstract": "Mammalian oocytes are notoriously prone to chromosome segregation errors leading to aneuploidy. The spindle provides the machinery for accurate chromosome segregation during cell division. Mammalian oocytes lack centrioles and, therefore, mouse meiotic spindle relies on the organization of numerous acentriolar microtubule organizing centers into two poles (polar microtubule organizing centers, pMTOCs). The traditional view is that, in mammalian oocytes, microtubules are the sole cytoskeletal component responsible for regulating pMTOC organization and spindle assembly. We identify a previously unrecognized F-actin pool that surrounds pMTOCs, forming F-actin cage-like structure. We demonstrate that F-actin localization on the spindle depends on unconventional myosins X and VIIb. Selective disruption of spindle-localized F-actin, using myosin X/VIIb knockdown oocytes or photoswitchable Optojasp-1, perturbs pMTOC organization, leading to unfocused spindle poles and chromosome missegregation. Here, we unveil an important function of spindle-localized\u00a0F-actin in regulating pMTOC organization, a critical process for ensuring the fidelity of meiotic spindle formation and proper chromosome segregation.", "doi": "10.1038/s41467-025-63586-w", "issn": "2041-1723", "publisher": "Nature Publishing Group", "publication": "Nature Communications", "publication_date": "2025-09-19", "series_number": "1", "volume": "16", "issue": "1", "pages": "8323" }, { "id": "authors:v16b0-swc65", "collection": "authors", "collection_id": "v16b0-swc65", "cite_using_url": "https://authors.library.caltech.edu/records/v16b0-swc65", "type": "article", "title": "Interactions of N- and C-terminal parts of Ana1 permitting centriole duplication but not elongation", "author": [ { "family_name": "Nagy", "given_name": "Agota", "orcid": "0000-0002-9510-0797", "clpid": "Nagy-Agota" }, { "family_name": "Kov\u00e1cs", "given_name": "Levente", "orcid": "0000-0002-3226-3740", "clpid": "Levente-Kov\u00e1cs" }, { "family_name": "Rangone", "given_name": "Helene", "orcid": "0000-0002-0744-4822" }, { "family_name": "Fu", "given_name": "Jingyan" }, { "family_name": "Ladinsky", "given_name": "Mark", "orcid": "0000-0002-1036-3513", "clpid": "Ladinsky-Mark-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "

The conserved process of centriole duplication requires the establishment of a Sas6-centred cartwheel initiated by Plk4's phosphorylation of Ana1/STIL. Subsequently, the centriole undergoes conversion to a centrosome requiring its radial expansion and elongation, mediated by a network requiring interactions between Cep135, Ana1/Cep295 and Asterless/Cep152. Here, we show that mutant alleles encoding overlapping N- and C-terminal parts of Ana1 are capable of intragenic complementation to rescue radial expansion. This permits the recruitment of Asl and thereby centriole duplication and mechanosensory cilia formation to restore the coordination defects of these mutants. This genetic combination also rescues centriole duplication in the male germ line but does not rescue the elongation of the triplet microtubule-containing centrioles of primary spermatocytes. Consequently, these males are coordinated but sterile. Such centriole elongation is rescued by the continuous, full-length Ana1 sequence. We define a region that when deleted within otherwise intact Ana1 does not permit primary spermatocyte centrioles to elongate but still allows recruitment of Asl. Our findings point to differing demands upon the physical organization of Ana1 for the distinct processes of radial expansion and elongation of centrioles.

", "doi": "10.1098/rsob.240325", "pmcid": "PMC11793955", "issn": "2046-2441", "publisher": "The Royal Society", "publication": "Open Biology", "publication_date": "2025-02", "series_number": "2", "volume": "15", "issue": "2", "pages": "240325" }, { "id": "authors:cmhcw-3j511", "collection": "authors", "collection_id": "cmhcw-3j511", "cite_using_url": "https://authors.library.caltech.edu/records/cmhcw-3j511", "type": "article", "title": "Protocol for preparing Drosophila genomic DNA to create chromosome-level de novo genome assemblies", "author": [ { "family_name": "Sperling", "given_name": "Alexis L.", "orcid": "0000-0001-6298-4832", "clpid": "Sperling-Alexis-L" }, { "family_name": "Fabian", "given_name": "Daniel K.", "orcid": "0000-0002-9895-2848", "clpid": "Fabian-Daniel-K" }, { "family_name": "Garrison", "given_name": "Erik", "orcid": "0000-0003-3821-631X", "clpid": "Garrison-Erik" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "
\n
\n

De novo genome assemblies are common tools for examining novel biological phenomena in non-model organisms. Here, we present a protocol for preparing Drosophila genomic DNA to create chromosome-level de novo genome assemblies. We describe steps for high-molecular-weight DNA preparation with phenol or Genomic-tips, quality control, long-read nanopore sequencing, short-read DNA library preparation, and sequencing. We then detail procedures of genome assembly, annotation, and assessment that can be used for downstream comparison and functional analysis.

\n

For complete details on the use and execution of this protocol, please refer to Sperling et al.1

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\n
\n
", "doi": "10.1016/j.xpro.2024.102974", "pmcid": "PMC11002874", "issn": "2666-1667", "publisher": "Cell Press", "publication": "STAR Protocols", "publication_date": "2024-06-21", "series_number": "2", "volume": "5", "issue": "2", "pages": "102974" }, { "id": "authors:p0c7c-e1m61", "collection": "authors", "collection_id": "p0c7c-e1m61", "cite_using_url": "https://authors.library.caltech.edu/records/p0c7c-e1m61", "type": "article", "title": "Greatwall-Endos-PP2A/B55\u1d40\u02b7\u1da6\u207f\u02e2 network regulates translation and stability of maternal transcripts in the Drosophila oocyte-to-embryo transition", "author": [ { "family_name": "Rangone", "given_name": "H\u00e9l\u00e8ne", "orcid": "0000-0002-0744-4822", "clpid": "Rangone-H\u00e9l\u00e8ne" }, { "family_name": "Bond", "given_name": "Laura", "orcid": "0000-0001-6115-655X", "clpid": "Bond-Laura-D" }, { "family_name": "Weil", "given_name": "Timothy T.", "orcid": "0000-0003-0490-849X", "clpid": "Weil-Timothy-T" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "
\n

The transition from oocyte to embryo requires translation of maternally provided transcripts that in Drosophila is activated by Pan Gu kinase to release a rapid succession of 13 mitotic cycles. Mitotic entry is promoted by several protein kinases that include Greatwall/Mastl, whose Endosulfine substrates antagonize Protein Phosphatase 2A (PP2A), facilitating mitotic Cyclin-dependent kinase 1/Cyclin B kinase activity. Here we show that hyperactive greatwallScant can not only be suppressed by mutants in its Endos substrate but also by mutants in Pan Gu kinase subunits. Conversely, mutants in me31B or trailer hitch, which encode a complex that represses hundreds of maternal mRNAs, enhance greatwallScant . Me31B and Trailer Hitch proteins, known substrates of Pan Gu kinase, copurify with Endos. This echoes findings that budding yeast Dhh1, orthologue of Me31B, associates with Igo1/2, orthologues of Endos and substrates of the Rim15, orthologue of Greatwall. endos-derived mutant embryos show reduced Me31B and elevated transcripts for the mitotic activators Cyclin B, Polo and Twine/Cdc25. Together, our findings demonstrate a previously unappreciated conservation of the Greatwall-Endosulfine pathway in regulating translational repressors and its interactions with the Pan Gu kinase pathway to regulate translation and/or stability of maternal mRNAs upon egg activation.

\n
", "doi": "10.1098/rsob.240065", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2024-06", "series_number": "6", "volume": "14", "issue": "6", "pages": "240065" }, { "id": "authors:jxhr6-3rs91", "collection": "authors", "collection_id": "jxhr6-3rs91", "cite_using_url": "https://authors.library.caltech.edu/records/jxhr6-3rs91", "type": "article", "title": "9-fold symmetry is not essential for centriole elongation and formation of new centriole-like structures", "author": [ { "family_name": "Panda", "given_name": "Pallavi", "orcid": "0000-0001-7572-6728", "clpid": "Panda-Pallavi" }, { "family_name": "Ladinsky", "given_name": "Mark S.", "orcid": "0000-0002-1036-3513", "clpid": "Ladinsky-Mark-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "
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\n

As daughter centrioles assemble during G2, they recruit conserved Ana3/RTTN followed by its partner Rcd4/PPP1R35. Together, this contributes to the subsequent recruitment of Ana1/CEP295, required for the centriole’s conversion to a centrosome. Here, we show that Rcd4/PPP1R35 is also required to maintain 9-fold centriole symmetry in the Drosophila male germline; its absence causes microtubule triplets to disperse into a reduced number of doublet or singlet microtubules. rcd4-null mutant spermatocytes display skinny centrioles that elongate normally and localize centriolar components correctly. Mutant spermatocytes also have centrioles of normal girth that splay at their proximal ends when induced to elongate by Ana1 overexpression. Skinny and splayed spermatid centrioles can still recruit a proximal centriole-like (PCL) structure marking a capability to initiate features of centriole duplication in developing sperm. Thus, stable 9-fold symmetry of microtubule triplets is not essential for centriole growth, correct longitudinal association of centriole components, and aspects of centriole duplication.

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\n
", "doi": "10.1038/s41467-024-48831-y", "pmcid": "PMC11127918", "issn": "2041-1723", "publisher": "Nature Publishing Group", "publication": "Nature Communications", "publication_date": "2024-05-25", "volume": "15", "pages": "4467" }, { "id": "authors:z9c19-88t83", "collection": "authors", "collection_id": "z9c19-88t83", "cite_using_url": "https://authors.library.caltech.edu/records/z9c19-88t83", "type": "article", "title": "Protocol for screening facultative parthenogenesis in Drosophila", "author": [ { "family_name": "Sperling", "given_name": "Alexis L.", "orcid": "0000-0001-6298-4832", "clpid": "Sperling-Alexis-L" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "

Most species of sexually reproducing Drosophila are capable of some degree of facultative parthenogenesis, which involves the initiation of development in an unfertilized egg. Here, we present an optimized protocol to screen facultative parthenogenesis in Drosophila. We describe steps for the collection and maintenance of virgin flies. We then detail offspring screening for the analysis of parthenogenesis. This protocol can be applied to different Drosophila strains and can be adapted for the analysis of parthenogenesis in other animals.

For complete details on the use and execution of this protocol, please refer to Sperling et al.1

", "doi": "10.1016/j.xpro.2023.102585", "pmcid": "PMC10520562", "issn": "2666-1667", "publisher": "Cell Press", "publication": "STAR Protocols", "publication_date": "2023-12-15", "series_number": "4", "volume": "4", "issue": "4", "pages": "102585" }, { "id": "authors:8pqja-mn072", "collection": "authors", "collection_id": "8pqja-mn072", "cite_using_url": "https://authors.library.caltech.edu/records/8pqja-mn072", "type": "article", "title": "Aneuploidy during development in facultative parthenogenetic Drosophila", "author": [ { "family_name": "Sperling", "given_name": "A. L.", "orcid": "0000-0001-6298-4832", "clpid": "Sperling-Alexis-L" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "

From concatenated chromosomes to polyploidization, large-scale genome changes are known to occur in parthenogenetic animals. Here, we report mosaic aneuploidy in larval brains of facultatively parthenogenetic Drosophila. We identified a background of aneuploidy in D. mercatorum strains and found increased levels of aneuploidy in the larval brain tissue of animals arising parthenogenetically versus those arising from sexual reproduction. There is also intra-individual variation in germline-derived aneuploidy within the same strain. To determine if this is a general feature of facultative parthenogenesis in drosophilids, we compared sexually reproduced and parthenogenetic offspring from an engineered facultative parthenogenetic strain of D. melanogaster. In addition to germline-derived aneuploidy, this revealed somatic aneuploidy that increased by up to fourfold in parthenogens compared to sexually reproduced offspring. Therefore, the genetic combination identified in D. mercatorum that causes facultative parthenogenesis in D. melanogaster results in aneuploidy, which indicates that the loss of mitotic control resulting in parthenogenesis causes subsequent genome variation within the parthenogenetic offspring. Our findings challenge the assumption that parthenogenetic offspring are near genetic replicas of their mothers.

", "doi": "10.1038/s41437-023-00664-z", "issn": "0018-067X", "publisher": "Nature Publishing Group", "publication": "Heredity", "publication_date": "2023-11-28" }, { "id": "authors:9adss-x9h08", "collection": "authors", "collection_id": "9adss-x9h08", "cite_using_url": "https://authors.library.caltech.edu/records/9adss-x9h08", "type": "article", "title": "A genetic basis for facultative parthenogenesis in Drosophila", "author": [ { "family_name": "Sperling", "given_name": "Alexis L.", "orcid": "0000-0001-6298-4832", "clpid": "Sperling-Alexis-L" }, { "family_name": "Fabian", "given_name": "Daniel K.", "orcid": "0000-0002-9895-2848", "clpid": "Fabian-Daniel-K" }, { "family_name": "Garrison", "given_name": "Erik", "orcid": "0000-0003-3821-631X", "clpid": "Garrison-Erik" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "

Facultative parthenogenesis enables sexually reproducing organisms to switch between sexual and asexual parthenogenetic reproduction. To gain insights into this phenomenon, we sequenced the genomes of sexually reproducing and parthenogenetic strains of Drosophila mercatorum and identified differences in the gene expression in their eggs. We then tested whether manipulating the expression of candidate gene homologs identified in Drosophila mercatorum could lead to facultative parthenogenesis in the non-parthenogenetic species Drosophila melanogaster. This identified a polygenic system whereby increased expression of the mitotic protein kinase polo and decreased expression of a desaturase, Desat2, caused facultative parthenogenesis in the non-parthenogenetic species that was enhanced by increased expression of Myc. The genetically induced parthenogenetic Drosophila melanogaster eggs exhibit de novo centrosome formation, fusion of the meiotic products, and the onset of development to generate predominantly triploid offspring. Thus, we demonstrate a genetic basis for sporadic facultative parthenogenesis in an animal.

", "doi": "10.1016/j.cub.2023.07.006", "pmcid": "PMC11044649", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2023-09-11", "series_number": "17", "volume": "33", "issue": "17", "pages": "3545-3560.e13" }, { "id": "authors:5bqk7-b1e47", "collection": "authors", "collection_id": "5bqk7-b1e47", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230602-251540000.11", "type": "article", "title": "Stem cell-derived synthetic embryos self-assemble by exploiting cadherin codes and cortical tension", "author": [ { "family_name": "Bao", "given_name": "Min", "orcid": "0000-0003-0992-9388", "clpid": "Bao-Min" }, { "family_name": "Cornwall-Scoones", "given_name": "Jake", "orcid": "0000-0002-7435-486X", "clpid": "Cornwall-Scoones-Jake" }, { "family_name": "Sanchez-Vasquez", "given_name": "Estefania", "orcid": "0000-0002-6585-8548", "clpid": "Sanchez-Vasquez-Estefania" }, { "family_name": "Cox", "given_name": "Andy L.", "clpid": "Cox-Andy-L" }, { "family_name": "Chen", "given_name": "Dong-Yuan", "orcid": "0000-0003-2179-2847", "clpid": "Chen-Dong-Yuan" }, { "family_name": "De Jonghe", "given_name": "Joachim", "orcid": "0000-0003-0584-8265", "clpid": "De-Jonghe-Joachim" }, { "family_name": "Shadkhoo", "given_name": "Shahriar", "orcid": "0000-0003-3582-0634", "clpid": "Shadkhoo-Shahriar" }, { "family_name": "Hollfelder", "given_name": "Florian", "orcid": "0000-0002-1367-6312", "clpid": "Hollfelder-Florian" }, { "family_name": "Thomson", "given_name": "Matt", "orcid": "0000-0003-1021-1234", "clpid": "Thomson-M-W" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Mammalian embryos sequentially differentiate into trophectoderm and an inner cell mass, the latter of which differentiates into primitive endoderm and epiblast. Trophoblast stem (TS), extraembryonic endoderm (XEN) and embryonic stem (ES) cells derived from these three lineages can self-assemble into synthetic embryos, but the mechanisms remain unknown. Here, we show that a stem cell-specific cadherin code drives synthetic embryogenesis. The XEN cell cadherin code enables XEN cell sorting into a layer below ES cells, recapitulating the sorting of epiblast and primitive endoderm before implantation. The TS cell cadherin code enables TS cell sorting above ES cells, resembling extraembryonic ectoderm clustering above epiblast following implantation. Whereas differential cadherin expression drives initial cell sorting, cortical tension consolidates tissue organization. By optimizing cadherin code expression in different stem cell lines, we tripled the frequency of correctly formed synthetic embryos. Thus, by exploiting cadherin codes from different stages of development, lineage-specific stem cells bypass the preimplantation structure to directly assemble a postimplantation embryo.", "doi": "10.1038/s41556-022-00984-y", "pmcid": "PMC9481465", "issn": "1465-7392", "publisher": "Nature Publishing Group", "publication": "Nature Cell Biology", "publication_date": "2023-09", "series_number": "9", "volume": "24", "issue": "9", "pages": "1341-2349" }, { "id": "authors:n9tz9-r2n12", "collection": "authors", "collection_id": "n9tz9-r2n12", "cite_using_url": "https://authors.library.caltech.edu/records/n9tz9-r2n12", "type": "article", "title": "Mob4 is essential for spermatogenesis in Drosophila melanogaster", "author": [ { "family_name": "Santos", "given_name": "In\u00eas B.", "clpid": "Santos-In\u00eas-B" }, { "family_name": "Wainman", "given_name": "Alan", "orcid": "0000-0002-6292-4183", "clpid": "Wainman-Alan" }, { "family_name": "Garrido-Maraver", "given_name": "Juan", "orcid": "0000-0003-4534-4109", "clpid": "Garrido-Maraver-Juan" }, { "family_name": "Pires", "given_name": "Vanessa", "orcid": "0000-0002-1514-685X", "clpid": "Pires-Vanessa" }, { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "orcid": "0000-0003-2084-019X", "clpid": "Riparbelli-Maria-Giovanna" }, { "family_name": "Kov\u00e1cs", "given_name": "Levente", "orcid": "0000-0002-3226-3740", "clpid": "Kov\u00e1cs-Levente" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-Giuliano" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Tavares", "given_name": "\u00c1lvaro A.", "orcid": "0000-0002-7137-0944", "clpid": "Tavares-\u00c1lvaro-A" } ], "abstract": "
\n

Gamete formation is essential for sexual reproduction in metazoans. Meiosis in males gives rise to spermatids that must differentiate and individualize into mature sperm. In Drosophila melanogaster, individualization of interconnected spermatids requires the formation of individualization complexes that synchronously move along the sperm bundles. Here, we show that Mob4, a member of the Mps-one binder family, is essential for male fertility but has no detectable role in female fertility. We show that Mob4 is required for proper axonemal structure and its loss leads to male sterility associated with defective spermatid individualization and absence of mature sperm in the seminal vesicles. Transmission electron micrographs of developing spermatids following mob4RNAi revealed expansion of the outer axonemal microtubules such that the 9 doublets no longer remained linked to each other and defective mitochondrial organization. Mob4 is a STRIPAK component, and male fertility is similarly impaired upon depletion of the STRIPAK components, Strip and Cka. Expression of the human Mob4 gene rescues all phenotypes of Drosophila mob4 downregulation, indicating that the gene is evolutionarily and functionally conserved. Together, this suggests that Mob4 contributes to the regulation of the microtubule- and actin-cytoskeleton during spermatogenesis through the conserved STRIPAK complex. Our study advances the understanding of male infertility by uncovering the requirement for Mob4 in sperm individualization.

\n
", "doi": "10.1093/genetics/iyad104", "pmcid": "PMC10411562", "issn": "1943-2631", "publisher": "Oxford University Press", "publication": "GENETICS", "publication_date": "2023-08", "series_number": "4", "volume": "224", "issue": "4", "pages": "iyad104" }, { "id": "authors:7ry8h-kf209", "collection": "authors", "collection_id": "7ry8h-kf209", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230726-217422400.25", "type": "article", "title": "Parthenogenesis in dipterans: a genetic perspective", "author": [ { "family_name": "Sperling", "given_name": "A. L.", "orcid": "0000-0001-6298-4832", "clpid": "Sperling-Alexis-L" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Parthenogenesis has been documented in almost every phylum of animals, and yet this phenomenon is largely understudied. It has particular importance in dipterans since some parthenogenetic species are also disease vectors and agricultural pests. Here, we present a catalogue of parthenogenetic dipterans, although it is likely that many more remain to be identified, and we discuss how their developmental biology and interactions with diverse environments may be linked to different types of parthenogenetic reproduction. We discuss how the advances in genetics and genomics have identified chromosomal loci associated with parthenogenesis. In particular, a polygenic cause of facultative parthenogenesis has been uncovered in Drosophila mercatorum, allowing the corresponding genetic variants to be tested for their ability to promote parthenogenesis in another species, Drosophila melanogaster. This study probably identifies just one of many routes that could be followed in the evolution of parthenogenesis. We attempt to account for why the phenomenon has evolved so many times in the dipteran order and why facultative parthenogenesis appears particularly prevalent. We also discuss the significance of coarse genomic changes, including non-disjunction, aneuploidy, and polyploidy and how, together with changes to specific genes, these might relate to both facultative and obligate parthenogenesis in dipterans and other parthenogenetic animals.", "doi": "10.1098/rspb.2023.0261", "pmcid": "PMC10031431", "issn": "0962-8452", "publisher": "Royal Society", "publication": "Proceedings of the Royal Society of London. Series B, Biological Sciences", "publication_date": "2023-03-29", "series_number": "1995", "volume": "290", "issue": "1995", "pages": "Art. No. 20230261" }, { "id": "authors:me6as-3t797", "collection": "authors", "collection_id": "me6as-3t797", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230124-9343400.1", "type": "article", "title": "Behind the developing brains and beating hearts of stem cell-derived embryo models", "author": [ { "family_name": "Amadei", "given_name": "Gianluca", "orcid": "0000-0001-5405-968X", "clpid": "Amadei-Gianluca" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Studies over the past decade have shown how stem cells representing embryonic and extra-embryonic tissues of the mouse can self-assemble in the culture dish to recapitulate an astonishing part of early embryonic development. A systematic analysis has demonstrated how pluripotent embryonic stem cells can be induced to behave like the implanting epiblast; how they can interact with trophectoderm stem cells to form a patterned structure resembling the implanting embryo prior to gastrulation; and how the third stem cell type\u2014extra-embryonic endoderm cells\u2014can be incorporated to generate structures that undergo the cell movements and gene expression patterns of gastrulation. Moreover, such stem cell-derived embryo models can proceed to neurulation and establish progenitors for all parts of the brain and neural tube, somites, beating heart structures and gut tube. They develop within extra-embryonic yolk sacs that initiate haematopoiesis. Here we trace this journey of discovery.", "doi": "10.1098/rsob.220325", "pmcid": "PMC9833437", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2023-01", "series_number": "1", "volume": "13", "issue": "1", "pages": "Art. No. rsob.220325" }, { "id": "authors:96ffw-mva24", "collection": "authors", "collection_id": "96ffw-mva24", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230301-701033500.4", "type": "article", "title": "Targeting Drosophila Sas6 to mitochondria reveals its high affinity for Gorab", "author": [ { "family_name": "Kovacs", "given_name": "Levente", "orcid": "0000-0002-3226-3740", "clpid": "Kovacs-Levente" }, { "family_name": "Fatalska", "given_name": "Agnieszka", "orcid": "0000-0002-1720-4742", "clpid": "Fatalska-Agnieszka" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The ability to relocalize proteins to defined subcellular locations presents a powerful tool to examine protein-protein interactions that can overcome a tendency of non-targeted exogenous proteins to form inaccessible aggregates. Here, we show that a 24-amino-acid sequence from the Drosophila proapoptotic protein Hid's tail anchor (HTA) domain can target exogenous proteins to the mitochondria in Drosophila cells. We use this HTA tag to target the Drosophila centriole cartwheel protein Sas6 to the mitochondria, and show that both exogenous and endogenous Gorab can be co-recruited from the Golgi to the new mitochondrial site. This accords with our previous observation that monomeric Drosophila Gorab binds Sas6 to become centriole associated with a 50-fold greater affinity than dimeric Gorab binds Rab6 to become localized at the Golgi. Strikingly, Drosophila Sas6 can bind both Drosophila Gorab and its human GORAB ortholog, whereas human SAS6 is unable to bind either GORAB or Gorab. We discuss these findings in relation to the evolutionary conservation of Gorab and the divergence of Sas6, possibly reflecting known differences in persistence of the cartwheel in the centriole duplication cycle of fly and human cells.", "doi": "10.1242/bio.059545", "pmcid": "PMC9836085", "issn": "2046-6390", "publisher": "Company of Biologists", "publication": "Biology Open", "publication_date": "2022-11-15", "series_number": "11", "volume": "11", "issue": "11", "pages": "Art. No. bio059545" }, { "id": "authors:ny5rx-x3886", "collection": "authors", "collection_id": "ny5rx-x3886", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221010-454096500.25", "type": "article", "title": "Embryo\u00a0model completes gastrulation to neurulation and organogenesis", "author": [ { "family_name": "Amadei", "given_name": "Gianluca", "orcid": "0000-0001-5405-968X", "clpid": "Amadei-Gianluca" }, { "family_name": "Handford", "given_name": "Charlotte E.", "orcid": "0000-0002-5245-8027", "clpid": "Handford-Charlotte-E" }, { "family_name": "Qiu", "given_name": "Chengxiang", "orcid": "0000-0002-6346-8669", "clpid": "Qiu-Chengxiang" }, { "family_name": "De Jonghe", "given_name": "Joachim", "orcid": "0000-0003-0584-8265", "clpid": "De-Jonghe-Joachim" }, { "family_name": "Greenfeld", "given_name": "Hannah", "clpid": "Greenfeld-Hannah" }, { "family_name": "Tran", "given_name": "Martin", "clpid": "Tran-Martin" }, { "family_name": "Martin", "given_name": "Beth K.", "orcid": "0000-0002-9661-014X", "clpid": "Martin-Beth-K" }, { "family_name": "Chen", "given_name": "Dong-Yuan", "orcid": "0000-0003-2179-2847", "clpid": "Chen-Dong-Yuan" }, { "family_name": "Aguilera-Castrejon", "given_name": "Alejandro", "orcid": "0000-0002-1339-7778", "clpid": "Aguilera-Castrejon-Alejandro" }, { "family_name": "Hanna", "given_name": "Jacob H.", "orcid": "0000-0003-2042-9974", "clpid": "Hanna-Jacob-H" }, { "family_name": "Elowitz", "given_name": "Michael B.", "orcid": "0000-0002-1221-0967", "clpid": "Elowitz-M-B" }, { "family_name": "Hollfelder", "given_name": "Florian", "orcid": "0000-0002-1367-6312", "clpid": "Hollfelder-Florian" }, { "family_name": "Shendure", "given_name": "Jay", "orcid": "0000-0002-1516-1865", "clpid": "Shendure-Jay" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Embryonic stem (ES) cells can undergo many aspects of mammalian embryogenesis in vitro, but their developmental potential is substantially extended by interactions with extraembryonic stem cells, including trophoblast stem (TS) cells, extraembryonic endoderm stem (XEN) cells and inducible XEN (iXEN) cells. Here we assembled stem cell-derived embryos in vitro from mouse ES cells, TS cells and iXEN cells and showed that they recapitulate the development of whole natural mouse embryo in utero up to day 8.5 post-fertilization. Our embryo model displays headfolds with defined forebrain and midbrain regions and develops a beating heart-like structure, a trunk comprising a neural tube and somites, a tail bud containing neuromesodermal progenitors, a gut tube, and primordial germ cells. This complete embryo model develops within an extraembryonic yolk sac that initiates blood island development. Notably, we demonstrate that the neurulating embryo model assembled from Pax6-knockout ES cells aggregated with wild-type TS cells and iXEN cells recapitulates the ventral domain expansion of the neural tube that occurs in natural, ubiquitous Pax6-knockout embryos. Thus, these complete embryoids are a powerful in vitro model for dissecting the roles of diverse cell lineages and genes in development. Our results demonstrate the self-organization ability of ES cells and two types of extraembryonic stem cells to reconstitute mammalian development through and beyond gastrulation to neurulation and early organogenesis.", "doi": "10.1038/s41586-022-05246-3", "pmcid": "PMC9534772", "issn": "0028-0836", "publisher": "Nature Publishing Group", "publication": "Nature", "publication_date": "2022-10-06", "series_number": "7930", "volume": "610", "issue": "7930", "pages": "143-153" }, { "id": "authors:am7bp-3g465", "collection": "authors", "collection_id": "am7bp-3g465", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220919-149101800", "type": "article", "title": "Stem cell-derived synthetic embryos self-assemble by exploiting cadherin codes and cortical tension", "author": [ { "family_name": "Bao", "given_name": "Min", "orcid": "0000-0003-0992-9388", "clpid": "Bao-Min" }, { "family_name": "Cornwall-Scoones", "given_name": "Jake", "orcid": "0000-0002-7435-486X", "clpid": "Cornwall-Scoones-Jake" }, { "family_name": "Sanchez-Vasquez", "given_name": "Estefania", "orcid": "0000-0002-6585-8548", "clpid": "Sanchez-Vasquez-Estefania" }, { "family_name": "Cox", "given_name": "Andy L.", "clpid": "Cox-Andy-L" }, { "family_name": "Chen", "given_name": "Dong-Yuan", "orcid": "0000-0003-2179-2847", "clpid": "Chen-Dong-Yuan" }, { "family_name": "De Jonghe", "given_name": "Joachim", "orcid": "0000-0003-0584-8265", "clpid": "De-Jonghe-Joachim" }, { "family_name": "Shadkhoo", "given_name": "Shahriar", "orcid": "0000-0003-3582-0634", "clpid": "Shadkhoo-Shahriar" }, { "family_name": "Hollfelder", "given_name": "Florian", "orcid": "0000-0002-1367-6312", "clpid": "Hollfelder-Florian" }, { "family_name": "Thomson", "given_name": "Matt", "orcid": "0000-0003-1021-1234", "clpid": "Thomson-M-W" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Mammalian embryos sequentially differentiate into trophectoderm and an inner cell mass, the latter of which differentiates into primitive endoderm and epiblast. Trophoblast stem (TS), extraembryonic endoderm (XEN) and embryonic stem (ES) cells derived from these three lineages can self-assemble into synthetic embryos, but the mechanisms remain unknown. Here, we show that a stem cell-specific cadherin code drives synthetic embryogenesis. The XEN cell cadherin code enables XEN cell sorting into a layer below ES cells, recapitulating the sorting of epiblast and primitive endoderm before implantation. The TS cell cadherin code enables TS cell sorting above ES cells, resembling extraembryonic ectoderm clustering above epiblast following implantation. Whereas differential cadherin expression drives initial cell sorting, cortical tension consolidates tissue organization. By optimizing cadherin code expression in different stem cell lines, we tripled the frequency of correctly formed synthetic embryos. Thus, by exploiting cadherin codes from different stages of development, lineage-specific stem cells bypass the preimplantation structure to directly assemble a postimplantation embryo.", "doi": "10.1038/s41556-022-00984-y", "pmcid": "PMC9481465", "issn": "1465-7392", "publisher": "Nature Publishing Group", "publication": "Nature Cell Biology", "publication_date": "2022-09-13", "series_number": "9", "volume": "24", "issue": "9", "pages": "1341-1349" }, { "id": "authors:8s30h-pv815", "collection": "authors", "collection_id": "8s30h-pv815", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210318-140520845", "type": "article", "title": "Mauve/LYST limits fusion of lysosome-related organelles and promotes centrosomal recruitment of microtubule nucleating proteins", "author": [ { "family_name": "Lattao", "given_name": "Ramona", "orcid": "0000-0002-1725-0175", "clpid": "Lattao-Ramona" }, { "family_name": "Rangone", "given_name": "H\u00e9l\u00e8ne", "orcid": "0000-0002-0744-4822", "clpid": "Rangone-H\u00e9l\u00e8ne" }, { "family_name": "Llamazares", "given_name": "Salud", "orcid": "0000-0002-8771-2312", "clpid": "Llamazares-Salud" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Lysosome-related organelles (LROs) are endosomal compartments carrying tissue-specific proteins, which become enlarged in Chediak-Higashi syndrome (CHS) due to mutations in LYST. Here, we show that Drosophila Mauve, a counterpart of LYST, suppresses vesicle fusion events with lipid droplets (LDs) during the formation of yolk granules (YGs), the LROs of the syncytial embryo, and opposes Rab5, which promotes fusion. Mauve localizes on YGs and at spindle poles, and it co-immunoprecipitates with the LDs' component and microtubule-associated protein Minispindles/Ch-TOG. Minispindles levels are increased at the enlarged YGs and diminished around centrosomes in mauve-derived mutant embryos. This leads to decreased microtubule nucleation from centrosomes, a defect that can be rescued by dominant-negative Rab5. Together, this reveals an unanticipated link between endosomal vesicles and centrosomes. These findings establish Mauve/LYST's role in regulating LRO formation and centrosome behavior, a role that could account for the enlarged LROs and centrosome positioning defects at the immune synapse of CHS patients.", "doi": "10.1016/j.devcel.2021.02.019", "pmcid": "PMC8024676", "issn": "1534-5807", "publisher": "Cell Press", "publication": "Developmental Cell", "publication_date": "2021-04-05", "series_number": "7", "volume": "56", "issue": "7", "pages": "1000-1013" }, { "id": "authors:2s3rv-qfm06", "collection": "authors", "collection_id": "2s3rv-qfm06", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210322-091153933", "type": "article", "title": "The dimeric Golgi protein Gorab binds to Sas6 as a monomer to mediate centriole duplication", "author": [ { "family_name": "Fatalska", "given_name": "Agnieszka", "orcid": "0000-0002-1720-4742", "clpid": "Fatalska-Agnieszka" }, { "family_name": "Stepinac", "given_name": "Emma", "clpid": "Stepinac-Emma" }, { "family_name": "Richter", "given_name": "Magdalena", "clpid": "Richter-Magdalena" }, { "family_name": "Kovacs", "given_name": "Levente", "orcid": "0000-0002-3226-3740", "clpid": "Kovacs-Levente" }, { "family_name": "Pietras", "given_name": "Zbigniew", "clpid": "Pietras-Zbigniew" }, { "family_name": "Puchinger", "given_name": "Martin", "clpid": "Puchinger-Martin" }, { "family_name": "Dong", "given_name": "Gang", "orcid": "0000-0001-9745-8103", "clpid": "Dong-Gang" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-Michal" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The duplication and ninefold symmetry of the Drosophila centriole requires that the cartwheel molecule, Sas6, physically associates with Gorab, a trans-Golgi component. How Gorab achieves these disparate associations is unclear. Here, we use hydrogen\u2013deuterium exchange mass spectrometry to define Gorab's interacting surfaces that mediate its subcellular localization. We identify a core stabilization sequence within Gorab's C-terminal coiled-coil domain that enables homodimerization, binding to Rab6, and thereby trans-Golgi localization. By contrast, part of the Gorab monomer's coiled-coil domain undergoes an antiparallel interaction with a segment of the parallel coiled-coil dimer of Sas6. This stable heterotrimeric complex can be visualized by electron microscopy. Mutation of a single leucine residue in Sas6's Gorab-binding domain generates a Sas6 variant with a sixteenfold reduced binding affinity for Gorab that cannot support centriole duplication. Thus, Gorab dimers at the Golgi exist in equilibrium with Sas6-associated monomers at the centriole to balance Gorab's dual role.", "doi": "10.7554/elife.57241", "pmcid": "PMC8009671", "issn": "2050-084X", "publisher": "eLife Sciences Publications", "publication": "eLife", "publication_date": "2021-03-11", "volume": "10", "pages": "Art. No. e57241" }, { "id": "authors:vkf2r-1tq59", "collection": "authors", "collection_id": "vkf2r-1tq59", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201224-085808015", "type": "article", "title": "Novel perspectives of target-binding by the evolutionarily conserved PP4 phosphatase", "author": [ { "family_name": "Karman", "given_name": "Zoltan", "clpid": "Karman-Zoltan" }, { "family_name": "Rethi-Nagy", "given_name": "Zsuzsanna", "clpid": "Rethi-Nagy-Zsuzsanna" }, { "family_name": "Abraham", "given_name": "Edit", "clpid": "Abraham-Edit" }, { "family_name": "Fabri-Ordogh", "given_name": "Lilla", "orcid": "0000-0003-0405-4017", "clpid": "Fabri-\u00d6rd\u00f6gh-Lilla" }, { "family_name": "Csonka", "given_name": "Akos", "orcid": "0000-0002-9628-6095", "clpid": "Csonka-\u00c1kos" }, { "family_name": "Vilmos", "given_name": "Peter", "orcid": "0000-0001-5692-8818", "clpid": "Vilmos-Peter" }, { "family_name": "Debski", "given_name": "Janusz", "orcid": "0000-0002-0171-7797", "clpid": "Debski-Janusz" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-Michal" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Zoltan" } ], "abstract": "Protein phosphatase 4 (PP4) is an evolutionarily conserved and essential Ser/Thr phosphatase that regulates cell division, development and DNA repair in eukaryotes. The major form of PP4, present from yeast to human, is the PP4c-R2-R3 heterotrimeric complex. The R3 subunit is responsible for substrate-recognition via its EVH1 domain. In typical EVH1 domains, conserved phenylalanine, tyrosine and tryptophan residues form the specific recognition site for their target's proline-rich sequences. Here, we identify novel binding partners of the EVH1 domain of the Drosophila R3 subunit, Falafel, and demonstrate that instead of binding to proline-rich sequences this EVH1 variant specifically recognizes atypical ligands, namely the FxxP and MxPP short linear consensus motifs. This interaction is dependent on an exclusively conserved leucine that replaces the phenylalanine invariant of all canonical EVH1 domains. We propose that the EVH1 domain of PP4 represents a new class of the EVH1 family that can accommodate low proline content sequences, such as the FxxP motif. Finally, our data implicate the conserved Smk-1 domain of Falafel in target-binding. These findings greatly enhance our understanding of the substrate-recognition mechanisms and function of PP4.", "doi": "10.1098/rsob.200343", "pmcid": "PMC7776573", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2020-12", "series_number": "12", "volume": "10", "issue": "12", "pages": "Art. No. 200343" }, { "id": "authors:zbzqg-55q85", "collection": "authors", "collection_id": "zbzqg-55q85", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201111-084020109", "type": "article", "title": "Interaction interface in the C-terminal parts of centriole proteins Sas6 and Ana2", "author": [ { "family_name": "Fatalska", "given_name": "Agnieszka", "orcid": "0000-0002-1720-4742", "clpid": "Fatalska-Agnieszka" }, { "family_name": "Dzhindzhev", "given_name": "Nikola S.", "orcid": "0000-0001-9866-3600", "clpid": "Dzhindzhev-Nikola-S" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-Michal" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The centriole is a ninefold symmetrical structure found at the core of centrosomes and, as a basal body, at the base of cilia, whose conserved duplication is regulated by Plk4 kinase. Plk4 phosphorylates a single serine residue at the N-terminus of Ana2 to promote Ana2's loading to the site of procentriole formation. Four conserved serines in Ana2's STAN motif are then phosphorylated by Plk4, enabling Sas6 recruitment. Crystallographic data indicate that the coiled\u2013coil domain of Ana2 forms a tetramer but the structure of full-length Ana2 has not been solved. Here, we have employed hydrogen\u2013deuterium exchange coupled with mass spectrometry (HDX-MS) to uncover the conformational dynamics of Ana2, revealing the high flexibility of this protein with one rigid region. To determine the elusive nature of the interaction surfaces between Ana2 and Sas6, we have confirmed complex formation between the phosphomimetic form of Ana2 (Ana2-4D) and Sas6 in vitro and in vivo. Analysis of this complex by HDX-MS identifies short critical regions required for this interaction, which lie in the C-terminal parts of both proteins. Mutational studies confirmed the relevance of these regions for the Ana2\u2013Sas6 interaction. The Sas6 site required for Ana2 binding is distinct from the site required for Sas6 to bind Gorab and Sas6 is able to bind both these protein partners simultaneously.", "doi": "10.1098/rsob.200221", "pmcid": "PMC7729032", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2020-11", "series_number": "11", "volume": "10", "issue": "11", "pages": "Art. No. 200221" }, { "id": "authors:15arw-j6s22", "collection": "authors", "collection_id": "15arw-j6s22", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200624-070312017", "type": "article", "title": "Tissue specific requirement of Drosophila Rcd4 for centriole duplication and ciliogenesis", "author": [ { "family_name": "Panda", "given_name": "Pallavi", "orcid": "0000-0001-7572-6728", "clpid": "Panda-Pallavi" }, { "family_name": "Kovacs", "given_name": "Levente", "orcid": "0000-0002-3226-3740", "clpid": "Kovacs-Levente" }, { "family_name": "Dzhindzhev", "given_name": "Nikola", "orcid": "0000-0001-9866-3600", "clpid": "Dzhindzhev-Nikola" }, { "family_name": "Fatalska", "given_name": "Agnieszka", "orcid": "0000-0002-1720-4742", "clpid": "Fatalska-Agnieszka" }, { "family_name": "Persico", "given_name": "Veronica", "clpid": "Persico-Veronica" }, { "family_name": "Geymonat", "given_name": "Marco", "orcid": "0000-0002-8792-0517", "clpid": "Geymonat-Marco" }, { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "clpid": "Riparbelli-Maria-Giovanna" }, { "family_name": "Callaini", "given_name": "Giuliano", "clpid": "Callaini-Giuliano" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Rcd4 is a poorly characterized Drosophila centriole component whose mammalian counterpart, PPP1R35, is suggested to function in centriole elongation and conversion to centrosomes. Here, we show that rcd4 mutants exhibit fewer centrioles, aberrant mitoses, and reduced basal bodies in sensory organs. Rcd4 interacts with the C-terminal part of Ana3, which loads onto the procentriole during interphase, ahead of Rcd4 and before mitosis. Accordingly, depletion of Ana3 prevents Rcd4 recruitment but not vice versa. We find that neither Ana3 nor Rcd4 participates directly in the mitotic conversion of centrioles to centrosomes, but both are required to load Ana1, which is essential for such conversion. Whereas ana3 mutants are male sterile, reflecting a requirement for Ana3 for centriole development in the male germ line, rcd4 mutants are fertile and have\nmale germ line centrioles of normal length. Thus, Rcd4 is essential in somatic cells but is not absolutely required in spermatogenesis, indicating tissue-specific roles in centriole and basal body formation.", "doi": "10.1083/jcb.201912154", "pmcid": "PMC7401805", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2020-09-07", "series_number": "8", "volume": "219", "issue": "8", "pages": "Art. No. e201912154" }, { "id": "authors:y1qv7-23k59", "collection": "authors", "collection_id": "y1qv7-23k59", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200805-090719433", "type": "article", "title": "Expression of SARS-CoV-2 receptor ACE2 and the protease TMPRSS2 suggests susceptibility of the human embryo in the first trimester", "author": [ { "family_name": "Weatherbee", "given_name": "Bailey A. T.", "clpid": "Weatherbee-B-A-T" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "While initially recognized as causing respiratory disease, the SARS-CoV-2 virus also affects many other organs leading to other complications. It has emerged that advanced age and obesity are risk factors for complications but questions concerning the potential effects on fetal health and successful pregnancy for those infected with SARS-CoV-2 remain largely unanswered. Here, we examine human pre-gastrulation embryos to determine the expression patterns of the genes ACE2, encoding the SARS-CoV-2 receptor, and TMPRSS2, encoding a protease that cleaves both the viral spike protein and the ACE2 receptor to facilitate infection. We show expression and co-expression of these genes in the trophoblast of the blastocyst and syncytiotrophoblast and hypoblast of the implantation stages, which develop into tissues that interact with the maternal blood supply for nutrient exchange. Expression of ACE2 and TMPRSS2 in these tissues raises the possibility for vertical transmission and indicates that further work is required to understand potential risks to implantation, placental health and fetal health that require further study.", "doi": "10.1098/rsob.200162", "pmcid": "PMC7479935", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2020-08", "series_number": "8", "volume": "10", "issue": "8", "pages": "200162" }, { "id": "authors:f9tsr-wbz63", "collection": "authors", "collection_id": "f9tsr-wbz63", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114540305", "type": "article", "title": "Open Biology in a new decade", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The end of the decade marks the end of my tenure as Editor-in-Chief of Open Biology. How far have we come since the launch of the journal in September 2011? This has certainly been a difficult time to start a new journal in molecular and cell biology, where the competition is fierce. We have made impact, however, with our dreaded Impact Factor oscillating between 3.5 and 5.8 during this time. I anticipate the metrics will soon rise higher because, most importantly, we are now recognized within the community as a journal that truly represents the interests of scientists. There has been a lot of debate about scientific publishing in the past decade and we have seen many new models emerge. We have watched this happen and taken up many suggestions from our readers and editorial board. While considering many different options, however, we have continued to follow a fairly traditional pattern of peer review. I believe this works well for us exactly because the journal is run by scientists for scientists and we know of the problems facing scientific publishing, particularly in molecular and cell biology, and wish to avoid them. It is vital that the academic academies and societies provide their members with publishing opportunities and indeed, the Royal Society serves us all well in this respect. Whereas competition from the publishing houses keeps us on our toes, our motivation is simply one of scientific communication to aid scientific progress.", "doi": "10.1098/rsob.200025", "pmcid": "PMC7058933", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2020-02", "series_number": "2", "volume": "10", "issue": "2", "pages": "Art. No. 200025" }, { "id": "authors:z504g-8q339", "collection": "authors", "collection_id": "z504g-8q339", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191216-145145496", "type": "article", "title": "Self-Organization of Mouse Stem Cells into an Extended Potential Blastoid", "author": [ { "family_name": "Sozen", "given_name": "Berna", "orcid": "0000-0001-5834-5819", "clpid": "Sozen-Berna" }, { "family_name": "Cox", "given_name": "Andy L.", "clpid": "Cox-Andy-L" }, { "family_name": "De Jonghe", "given_name": "Joachim", "orcid": "0000-0003-0584-8265", "clpid": "De-Jonghe-Joachim" }, { "family_name": "Bao", "given_name": "Min", "orcid": "0000-0003-0992-9388", "clpid": "Bao-Min" }, { "family_name": "Hollfelder", "given_name": "Florian", "orcid": "0000-0002-1367-6312", "clpid": "Hollfelder-Florian" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Mammalian blastocysts comprise three distinct cell lineages essential for development beyond implantation: the pluripotent epiblast, which generates the future embryo, and surrounding it the extra-embryonic primitive endoderm and the trophectoderm tissues. Embryonic stem cells can reintegrate into embryogenesis but contribute primarily to epiblast lineages. Here, we show that mouse embryonic stem cells cultured under extended pluripotent conditions (EPSCs) can be partnered with trophoblast stem cells to self-organize into blastocyst-like structures with all three embryonic and extra-embryonic lineages. Morphogenetic and transcriptome profiling analyses reveal that these blastocyst-like structures show distinct embryonic-abembryonic axes and primitive endoderm differentiation and can initiate the transition from the pre- to post-implantation egg cylinder morphology in vitro.", "doi": "10.1016/j.devcel.2019.11.014", "pmcid": "PMC10291877", "issn": "1534-5807", "publisher": "Cell Press", "publication": "Developmental Cell", "publication_date": "2019-12-16", "series_number": "6", "volume": "51", "issue": "6", "pages": "698-712" }, { "id": "authors:2060x-eb964", "collection": "authors", "collection_id": "2060x-eb964", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114540416", "type": "article", "title": "2018: a year in review for Open Biology", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "A new year is with us again and Open Biology moves forward to meet new challenges in the ever-changing world of scientific publishing. Hopefully, we manage to keep the best of the old while keeping abreast of the new.", "doi": "10.1098/rsob.190015", "pmcid": "PMC6367131", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2019-01", "series_number": "1", "volume": "9", "issue": "1", "pages": "Art. No. 190015" }, { "id": "authors:1vvst-jnr69", "collection": "authors", "collection_id": "1vvst-jnr69", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190408-111045813", "type": "article", "title": "CARM1 and Paraspeckles Regulate Pre-implantation Mouse Embryo Development", "author": [ { "family_name": "Hupalowska", "given_name": "Anna", "clpid": "Hupalowsk-A" }, { "family_name": "Jedrusik", "given_name": "Agnieszka", "clpid": "Jedrusik-A" }, { "family_name": "Zhu", "given_name": "Meng", "orcid": "0000-0001-6157-8840", "clpid": "Zhu-Meng" }, { "family_name": "Bedford", "given_name": "Mark T.", "clpid": "Bedford-M-T" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Nuclear architecture has never been carefully examined during early mammalian development at the stages leading to establishment of the embryonic and extra-embryonic lineages. Heterogeneous activity of the methyltransferase CARM1 during these stages results in differential methylation of histone H3R26 to modulate establishment of these two lineages. Here we show that CARM1 accumulates in nuclear granules at the 2- to 4-cell stage transition in the mouse embryo, with the majority corresponding to paraspeckles. The paraspeckle component Neat1 and its partner p54nrb are required for CARM1's association with paraspeckles and for H3R26 methylation. Conversely, CARM1 also influences paraspeckle organization. Depletion of Neat1 or p54nrb results in arrest at the 16- to 32-cell stage, with elevated expression of transcription factor Cdx2, promoting differentiation into the extra-embryonic lineage. This developmental arrest occurs at an earlier stage than following CARM1 depletion, indicating that paraspeckles act upstream of CARM1 but also have additional earlier roles in fate choice.", "doi": "10.1016/j.cell.2018.11.027", "pmcid": "PMC6292842", "issn": "0092-8674", "publisher": "Elsevier", "publication": "Cell", "publication_date": "2018-12-13", "series_number": "7", "volume": "175", "issue": "7", "pages": "1902-1916.e13" }, { "id": "authors:pwkq4-zzr83", "collection": "authors", "collection_id": "pwkq4-zzr83", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190408-111046182", "type": "article", "title": "Self-assembly of embryonic and two extra-embryonic stem cell types into gastrulating embryo-like structures", "author": [ { "family_name": "Sozen", "given_name": "Berna", "orcid": "0000-0001-5834-5819", "clpid": "Sozen-B" }, { "family_name": "Amadei", "given_name": "Gianluca", "clpid": "Amadei-G" }, { "family_name": "Cox", "given_name": "Andy", "clpid": "Cox-Andy" }, { "family_name": "Wang", "given_name": "Ran", "orcid": "0000-0003-4956-5742", "clpid": "Wang-Ran" }, { "family_name": "Na", "given_name": "Ellen", "orcid": "0000-0003-1395-9707", "clpid": "Na-Ellen" }, { "family_name": "Czukiewska", "given_name": "Sylwia", "clpid": "Czukiewska-S" }, { "family_name": "Chappell", "given_name": "Lia", "clpid": "Chappell-L" }, { "family_name": "Voet", "given_name": "Thierry", "clpid": "Voet-T" }, { "family_name": "Michel", "given_name": "Geert", "clpid": "Michel-G" }, { "family_name": "Jing", "given_name": "Naihe", "orcid": "0000-0003-1509-6378", "clpid": "Jing-Naihe" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Embryonic stem cells can be incorporated into the developing embryo and its germ line, but, when cultured alone, their ability to generate embryonic structures is restricted. They can interact with trophoblast stem cells to generate structures that break symmetry and specify mesoderm, but their development is limited as the epithelial\u2013mesenchymal transition of gastrulation cannot occur. Here, we describe a system that allows assembly of mouse embryonic, trophoblast and extra-embryonic endoderm stem cells into structures that acquire the embryo's architecture with all distinct embryonic and extra-embryonic compartments. Strikingly, such embryo-like structures develop to undertake the epithelial\u2013mesenchymal transition, leading to mesoderm and then definitive endoderm specification. Spatial transcriptomic analyses demonstrate that these morphological transformations are underpinned by gene expression patterns characteristic of gastrulating embryos. This demonstrates the remarkable ability of three stem cell types to self-assemble in vitro into gastrulating embryo-like structures undertaking spatio-temporal events of the gastrulating mammalian embryo.", "doi": "10.1038/s41556-018-0147-7", "issn": "1465-7392", "publisher": "Nature Publishing Group", "publication": "Nature Cell Biology", "publication_date": "2018-08", "series_number": "8", "volume": "20", "issue": "8", "pages": "979-989" }, { "id": "authors:kqdcb-tbz42", "collection": "authors", "collection_id": "kqdcb-tbz42", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114540050", "type": "article", "title": "Gorab is a Golgi protein required for structure and duplication of Drosophila centrioles", "author": [ { "family_name": "Kovacs", "given_name": "Levente", "orcid": "0000-0002-3226-3740", "clpid": "Kovacs-Levente" }, { "family_name": "Chao-Chu", "given_name": "Jennifer", "orcid": "0000-0001-6740-8797", "clpid": "Chao-Chu-Jennifer" }, { "family_name": "Schneider", "given_name": "Sandra", "clpid": "Schneider-Sandra" }, { "family_name": "Gottardo", "given_name": "Marco", "orcid": "0000-0001-8649-7799", "clpid": "Gottardo-Marco" }, { "family_name": "Tzolovsky", "given_name": "George", "clpid": "Tzolovsky-G" }, { "family_name": "Dzhindzhev", "given_name": "Nikola S.", "orcid": "0000-0001-9866-3600", "clpid": "Dzhindzhev-N-S" }, { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "clpid": "Riparbelli-M-G" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We demonstrate that a Drosophila Golgi protein, Gorab, is present not only in the trans-Golgi but also in the centriole cartwheel where, complexed to Sas6, it is required for centriole duplication. In addition to centriole defects, flies lacking Gorab are uncoordinated due to defects in sensory cilia, which lose their nine-fold symmetry. We demonstrate the separation of centriole and Golgi functions of Drosophila Gorab in two ways: first, we have created Gorab variants that are unable to localize to trans-Golgi but can still rescue the centriole and cilia defects of gorab null flies; second, we show that expression of C-terminally tagged Gorab disrupts Golgi functions in cytokinesis of male meiosis, a dominant phenotype overcome by mutations preventing Golgi targeting. Our findings suggest that during animal evolution, a Golgi protein has arisen with a second, apparently independent, role in centriole duplication.", "doi": "10.1038/s41588-018-0149-1", "pmcid": "PMC6097609", "issn": "1061-4036", "publisher": "Nature Publishing Group", "publication": "Nature Genetics", "publication_date": "2018-07", "series_number": "7", "volume": "50", "issue": "7", "pages": "1021-1031" }, { "id": "authors:5bgvt-sh520", "collection": "authors", "collection_id": "5bgvt-sh520", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114540635", "type": "article", "title": "Constitutive regulation of mitochondrial morphology by Aurora A kinase depends on a predicted cryptic targeting sequence at the N-terminus", "author": [ { "family_name": "Grant", "given_name": "Rhys", "orcid": "0000-0003-4027-0972", "clpid": "Grant-Rhys" }, { "family_name": "Abdelbaki", "given_name": "Ahmed", "orcid": "0000-0002-9151-3113", "clpid": "Abdelbaki-Ahmed" }, { "family_name": "Bertoldi", "given_name": "Alessia", "orcid": "0000-0002-5929-2269", "clpid": "Bertoldi-Alessia" }, { "family_name": "Gavilan", "given_name": "Maria P.", "orcid": "0000-0003-3694-8525", "clpid": "Gavilan-M-P" }, { "family_name": "Mansfeld", "given_name": "J\u00f6rg", "orcid": "0000-0002-0562-8206", "clpid": "Mansfield-J\u00f6rg" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Lindon", "given_name": "Catherine", "orcid": "0000-0003-3554-2574", "clpid": "Lindon-Catherine" } ], "abstract": "Aurora A kinase (AURKA) is a major regulator of mitosis and an important driver of cancer progression. The roles of AURKA outside of mitosis, and how these might contribute to cancer progression, are not well understood. Here, we show that a fraction of cytoplasmic AURKA is associated with mitochondria, co-fractionating in cell extracts and interacting with mitochondrial proteins by reciprocal co-immunoprecipitation. We have also found that the dynamics of the mitochondrial network are sensitive to AURKA inhibition, depletion or overexpression. This can account for the different mitochondrial morphologies observed in RPE-1 and U2OS cell lines, which show very different levels of expression of AURKA. We identify the mitochondrial fraction of AURKA as influencing mitochondrial morphology, because an N-terminally truncated version of the kinase that does not localize to mitochondria does not affect the mitochondrial network. We identify a cryptic mitochondrial targeting sequence in the AURKA N-terminus and discuss how alternative conformations of the protein may influence its cytoplasmic fate.", "doi": "10.1098/rsob.170272", "pmcid": "PMC6030116", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2018-06", "series_number": "6", "volume": "8", "issue": "6", "pages": "Art. No. 170272" }, { "id": "authors:1a0xb-6sd70", "collection": "authors", "collection_id": "1a0xb-6sd70", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114540540", "type": "article", "title": "New Year's revolution", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "It is hard to believe that it is already time again to greet another New Year but once again, it is a good opportunity to take stock of how far Open Biology has come, where we are going, and whether we are on the right track. As scientific publishing goes through perhaps its most profound revolution because it was established over 350 years ago, these are questions that we need to keep very much in mind.", "doi": "10.1098/rsob.180005", "pmcid": "PMC5795058", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2018-01", "series_number": "1", "volume": "8", "issue": "1", "pages": "Art. No. 180005" }, { "id": "authors:jxacb-pds65", "collection": "authors", "collection_id": "jxacb-pds65", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114540947", "type": "article", "title": "Two-step phosphorylation of Ana2 by Plk4 is required for the sequential loading of Ana2 and Sas6 to initiate procentriole formation", "author": [ { "family_name": "Dzhindzhev", "given_name": "Nikola S.", "orcid": "0000-0001-9866-3600", "clpid": "Dzhindzhev-N-S" }, { "family_name": "Tzolovsky", "given_name": "George", "clpid": "Tzolovsky-G" }, { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Z" }, { "family_name": "Abdelaziz", "given_name": "Mohammed", "clpid": "Abdelaziz-Mohammed" }, { "family_name": "Debski", "given_name": "Janus", "orcid": "0000-0002-0171-7797", "clpid": "Debski-J" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The conserved process of centriole duplication requires Plk4 kinase to recruit and promote interactions between Sas6 and Sas5/Ana2/STIL (respective nomenclature of worms/flies/humans). Plk4-mediated phosphorylation of Ana2/STIL in its conserved STAN motif has been shown to promote its interaction with Sas6. However, STAN motif phosphorylation is not required for recruitment of Ana2 to the centriole. Here we show that in Drosophila, Ana2 loads onto the site of procentriole formation ahead of Sas6 in a process that also requires Plk4. However, whereas Plk4 is first recruited to multiple sites around the ring of zone II at the periphery of the centriole, Ana2 is recruited to a single site in telophase before Plk4 becomes finally restricted to this same single site. When we over-ride the auto-destruction of Plk4, it remains localized to multiple sites in the outer ring of the centriole and, if catalytically active, recruits Ana2 to these sites. Thus, it is the active form of Plk4 that promotes Ana2's recruitment to the centriole. We now show that Plk4 phosphorylates Ana2 at a site other than the STAN motif, which lies in a conserved region we term the ANST (ANa2-STil) motif. Mutation of this site, S38, to a non-phosphorylatable residue prevents the procentriole loading of Ana2 and blocks centriole duplication. Thus the initiation of procentriole formation requires Plk4 to first phosphorylate a single serine residue in the ANST motif to promote Ana2's recruitment and, secondly, to phosphorylate four residues in the STAN motif enabling Ana2 to recruit Sas6. We discuss these findings in light of the multiple Plk4 phosphorylation sites on Ana2.", "doi": "10.1098/rsob.170247", "pmcid": "PMC5746551", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2017-12", "series_number": "12", "volume": "7", "issue": "12", "pages": "Art. No. 170247" }, { "id": "authors:63361-5pn82", "collection": "authors", "collection_id": "63361-5pn82", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190408-162605585", "type": "article", "title": "Plk4 and Aurora A cooperate in the initiation of acentriolar spindle assembly in mammalian oocytes", "author": [ { "family_name": "Bury", "given_name": "Leah", "orcid": "0000-0002-6218-2837", "clpid": "Bury-Leah" }, { "family_name": "Coelho", "given_name": "Paula A.", "orcid": "0000-0003-0614-7575", "clpid": "Coelho-Paula-A" }, { "family_name": "Simeone", "given_name": "Angela", "clpid": "Simeone-Angela" }, { "family_name": "Ferries", "given_name": "Samantha", "clpid": "Ferries-Samantha" }, { "family_name": "Eyers", "given_name": "Claire E.", "orcid": "0000-0002-3223-5926", "clpid": "Eyers-Claire-E" }, { "family_name": "Eyers", "given_name": "Patrick A.", "orcid": "0000-0002-9220-2966", "clpid": "Eyers-Patrick-A" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Establishing the bipolar spindle in mammalian oocytes after their prolonged arrest is crucial for meiotic fidelity and subsequent development. In contrast to somatic cells, the first meiotic spindle assembles in the absence of centriole-containing centrosomes. Ran-GTP can promote microtubule nucleation near chromatin, but additional unidentified factors are postulated for the activity of multiple acentriolar microtubule organizing centers in the oocyte. We now demonstrate that partially overlapping, nonredundant functions of Aurora A and Plk4 kinases contribute to initiate acentriolar meiosis I spindle formation. Loss of microtubule nucleation after simultaneous chemical inhibition of both kinases can be significantly rescued by drug-resistant Aurora A alone. Drug-resistant Plk4 can enhance Aurora A\u2013mediated rescue, and, accordingly, Plk4 can phosphorylate and potentiate the activity of Aurora A in vitro. Both kinases function distinctly from Ran, which amplifies microtubule growth. We conclude that Aurora A and Plk4 are rate-limiting factors contributing to microtubule growth as the acentriolar oocyte resumes meiosis.", "doi": "10.1083/jcb.201606077", "pmcid": "PMC5674873", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2017-11-06", "series_number": "11", "volume": "216", "issue": "11", "pages": "3571-3590" }, { "id": "authors:70245-bbk69", "collection": "authors", "collection_id": "70245-bbk69", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150624614", "type": "article", "title": "The Centrioles, Centrosomes, Basal Bodies, and Cilia of Drosophila melanogaster", "author": [ { "family_name": "Lattao", "given_name": "Ramona", "orcid": "0000-0002-1725-0175", "clpid": "Lattao-Ramona" }, { "family_name": "Kovacs", "given_name": "Levente", "orcid": "0000-0002-3226-3740", "clpid": "Kovacs-Levente" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Centrioles play a key role in the development of the fly. They are needed for the correct formation of centrosomes, the organelles at the poles of the spindle that can persist as microtubule organizing centers (MTOCs) into interphase. The ability to nucleate cytoplasmic microtubules (MTs) is a property of the surrounding pericentriolar material (PCM). The centriole has a dual life, existing not only as the core of the centrosome but also as the basal body, the structure that templates the formation of cilia and flagellae. Thus the structure and functions of the centriole, the centrosome, and the basal body have an impact upon many aspects of development and physiology that can readily be modeled in Drosophila Centrosomes are essential to give organization to the rapidly increasing numbers of nuclei in the syncytial embryo and for the spatially precise execution of cell division in numerous tissues, particularly during male meiosis. Although mitotic cell cycles can take place in the absence of centrosomes, this is an error-prone process that opens up the fly to developmental defects and the potential of tumor formation. Here, we review the structure and functions of the centriole, the centrosome, and the basal body in different tissues and cultured cells of Drosophila melanogaster, highlighting their contributions to different aspects of development and cell division.", "doi": "10.1534/genetics.116.198168", "pmcid": "PMC5419478", "issn": "0016-6731", "publisher": "Genetics Society of America", "publication": "Genetics", "publication_date": "2017-05", "series_number": "1", "volume": "206", "issue": "1", "pages": "33-53" }, { "id": "authors:cf5qn-19t13", "collection": "authors", "collection_id": "cf5qn-19t13", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353624", "type": "article", "title": "Editorial: Aurora Kinases: Classical Mitotic Roles, Non-Canonical Functions and Translational Views", "author": [ { "family_name": "P\u00e9rez de Castro", "given_name": "Ignacio", "clpid": "P\u00e9rez-de-Castro-I" }, { "family_name": "Carmena", "given_name": "Mar", "orcid": "0000-0002-2352-1066", "clpid": "Carmena-M" }, { "family_name": "Prigent", "given_name": "Claude", "orcid": "0000-0001-8515-8699", "clpid": "Prigent-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Aurora kinases are key mitotic regulators that have also been associated with tumor development and progression. The interest on this highly conserved family of protein kinases has grown exponentially since they were discovered in the 1990s. Despite the steady increase in the number of laboratories involved and the consequent boost of the volume of research output during the last years, the study of Aurora kinases remains a very dynamic area in which new discoveries frequently keep coming to light. From a clinical perspective, the interest on Aurora kinase biology stems from their identification as targets for drug development; an increasing number of Aurora kinase inhibitors are being tested in preclinical projects and clinical trials. In this Frontiers Research Topic, we have aimed to not only review and revisit different aspects of the functions and regulation of Aurora kinases but also provide a forum for the publication of new developments in the field. We have been privileged to count on contributions from authors and reviewers that include some of the most experienced voices in our research area.\n\nIn their introductory article to the Research Topic, two old-timers in the field, David Glover and Bill Earnshaw, have provided a historical perspective of Aurora Kinase research. By looking at the field's origin using genetic screens in Drosophila and yeast and cell biological studies in vertebrates that led to the identification of Aurora kinases and their partner proteins, the authors give us a unique first witness account of the development of the field (Carmena et al.).", "doi": "10.3389/fonc.2017.00048", "pmcid": "PMC5360697", "issn": "2234-943X", "publisher": "Frontiers Research Foundation", "publication": "Frontiers in Oncology", "publication_date": "2017-03-22", "volume": "7", "pages": "Art. No. 48" }, { "id": "authors:csbr3-0x560", "collection": "authors", "collection_id": "csbr3-0x560", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541151", "type": "article", "title": "Rab1 interacts with GOLPH3 and controls Golgi structure and contractile ring constriction during cytokinesis in Drosophila melanogaster", "author": [ { "family_name": "Sechi", "given_name": "Stefano", "orcid": "0000-0003-4253-6770", "clpid": "Sechi-Stefano" }, { "family_name": "Frappaolo", "given_name": "Anna", "orcid": "0000-0002-3270-4139", "clpid": "Frappaolo-A" }, { "family_name": "Fraschini", "given_name": "Roberta", "orcid": "0000-0001-8441-4080", "clpid": "Fraschini-Roberta" }, { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Gottardo", "given_name": "Marco", "orcid": "0000-0001-8649-7799", "clpid": "Gottardo-M" }, { "family_name": "Belloni", "given_name": "Giorgio", "clpid": "Belloni-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Wainman", "given_name": "Alan", "orcid": "0000-0002-6292-4183", "clpid": "Wainman-A" }, { "family_name": "Giansanti", "given_name": "Maria Grazia", "orcid": "0000-0002-6753-7262", "clpid": "Giansanti-M-G" } ], "abstract": "Cytokinesis requires a tight coordination between actomyosin ring constriction and new membrane addition along the ingressing cleavage furrow. However, the molecular mechanisms underlying vesicle trafficking to the equatorial site and how this process is coupled with the dynamics of the contractile apparatus are poorly defined. Here we provide evidence for the requirement of Rab1 during cleavage furrow ingression in cytokinesis. We demonstrate that the gene omelette (omt) encodes the Drosophila orthologue of human Rab1 and is required for successful cytokinesis in both mitotic and meiotic dividing cells of Drosophila melanogaster. We show that Rab1 protein colocalizes with the conserved oligomeric Golgi (COG) complex Cog7 subunit and the phosphatidylinositol 4-phosphate effector GOLPH3 at the Golgi stacks. Analysis by transmission electron microscopy and 3D-SIM super-resolution microscopy reveals loss of normal Golgi architecture in omt mutant spermatocytes indicating a role for Rab1 in Golgi formation. In dividing cells, Rab1 enables stabilization and contraction of actomyosin rings. We further demonstrate that GTP-bound Rab1 directly interacts with GOLPH3 and controls its localization at the Golgi and at the cleavage site. We propose that Rab1, by associating with GOLPH3, controls membrane trafficking and contractile ring constriction during cytokinesis.", "doi": "10.1098/rsob.160257", "pmcid": "PMC5303273", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2017-01", "series_number": "1", "volume": "7", "issue": "1", "pages": "Art. No. 160257" }, { "id": "authors:8ab4r-2a057", "collection": "authors", "collection_id": "8ab4r-2a057", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541047", "type": "article", "title": "A new world for Open Biology", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The New Year is an excellent time to welcome the 38 new members to the editorial board of Open Biology (http://rsob.royalsocietypublishing.org/editorial-board). They are leading scientists from the USA, Canada and China who we hope will be champions for the journal in these countries and beyond. We are truly delighted to have these scientists join us.", "doi": "10.1098/rsob.170002", "pmcid": "PMC5303283", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2017-01", "series_number": "1", "volume": "7", "issue": "1", "pages": "Art. No. 170002" }, { "id": "authors:9tcp4-5sp63", "collection": "authors", "collection_id": "9tcp4-5sp63", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170354727", "type": "article", "title": "Targeting of Fzr/Cdh1 for timely activation of the APC/C at the centrosome during mitotic exit", "author": [ { "family_name": "Meghini", "given_name": "Francesco", "clpid": "Meghini-F" }, { "family_name": "Martins", "given_name": "Torcato", "orcid": "0000-0002-9359-7111", "clpid": "Martins-Torcato" }, { "family_name": "Tait", "given_name": "Xavier", "clpid": "Tait-X" }, { "family_name": "Fujimitsu", "given_name": "Kazuyuki", "clpid": "Fujimitsu-Kazuyuki" }, { "family_name": "Yamano", "given_name": "Hiroyuki", "clpid": "Yamano-Hiroyuki" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Kimata", "given_name": "Yuu", "orcid": "0000-0001-6223-1320", "clpid": "Kimata-Yuu" } ], "abstract": "A multi-subunit ubiquitin ligase, the anaphase-promoting complex/cyclosome (APC/C), regulates critical cellular processes including the cell cycle. To accomplish its diverse functions, APC/C activity must be precisely regulated in time and space. The interphase APC/C activator Fizzy-related (Fzr or Cdh1) is localized at centrosomes in animal cells. However, neither the mechanism of its localization nor its importance is clear. Here we identify the centrosome component Spd2 as a major partner of Fzr in Drosophila. The localization of Fzr to the centriole during interphase depends on direct interaction with Spd2. By generating Spd2 mutants unable to bind Fzr, we show that centrosomal localization of Fzr is essential for optimal APC/C activation towards its centrosomal substrate Aurora A. Finally, we show that Spd2 is also a novel APC/C^(Fzr) substrate. Our study is the first to demonstrate the critical importance of distinct subcellular pools of APC/C activators in the spatiotemporal control of APC/C activity.", "doi": "10.1038/ncomms12607", "pmcid": "PMC5007356", "issn": "2041-1723", "publisher": "Nature Publishing Group", "publication": "Nature Communications", "publication_date": "2016-08-25", "volume": "7", "pages": "Art. No. 12607" }, { "id": "authors:dyvz5-1sg59", "collection": "authors", "collection_id": "dyvz5-1sg59", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541361", "type": "article", "title": "Network of protein interactions within the Drosophila inner kinetochore", "author": [ { "family_name": "Richter", "given_name": "Magdalena M.", "clpid": "Richter-M-M" }, { "family_name": "Poznanski", "given_name": "Jaroslaw", "orcid": "0000-0003-2684-1775", "clpid": "Poznanski-J" }, { "family_name": "Zdziarska", "given_name": "Anna", "clpid": "Zdziarska-A" }, { "family_name": "Czarnocki-Cieciura", "given_name": "Mariusz", "orcid": "0000-0001-5582-2851", "clpid": "Czarnocki-Cieciura-M" }, { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Z" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" } ], "abstract": "The kinetochore provides a physical connection between microtubules and the centromeric regions of chromosomes that is critical for their equitable segregation. The trimeric Mis12 sub-complex of the Drosophila kinetochore binds to the mitotic centromere using CENP-C as a platform. However, knowledge of the precise connections between Mis12 complex components and CENP-C has remained elusive despite the fundamental importance of this part of the cell division machinery. Here, we employ hydrogen\u2013deuterium exchange coupled with mass spectrometry to reveal that Mis12 and Nnf1 form a dimer maintained by interacting coiled-coil (CC) domains within the carboxy-terminal parts of both proteins. Adjacent to these interacting CCs is a carboxy-terminal domain that also interacts with Nsl1. The amino-terminal parts of Mis12 and Nnf1 form a CENP-C-binding surface, which docks the complex and thus the entire kinetochore to mitotic centromeres. Mutational analysis confirms these precise interactions are critical for both structure and function of the complex. Thus, we conclude the organization of the Mis12\u2013Nnf1 dimer confers upon the Mis12 complex a bipolar, elongated structure that is critical for kinetochore function.", "doi": "10.1098/rsob.150238", "pmcid": "PMC4772809", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2016-02", "series_number": "2", "volume": "6", "issue": "2", "pages": "Art. No. 150238" }, { "id": "authors:q6cgq-93x38", "collection": "authors", "collection_id": "q6cgq-93x38", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170349570", "type": "article", "title": "Conserved molecular interactions in centriole-to-centrosome conversion", "author": [ { "family_name": "Fu", "given_name": "Jingyan", "orcid": "0000-0002-5896-8132", "clpid": "Fu-Jingyan" }, { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Z" }, { "family_name": "Rangone", "given_name": "H\u00e9l\u00e8ne", "clpid": "Rangone-H" }, { "family_name": "Min", "given_name": "Mingwei", "clpid": "Min-Mingwei" }, { "family_name": "Mykura", "given_name": "Charlotte", "clpid": "Mykura-Charlotte" }, { "family_name": "Chao-Chu", "given_name": "Jennifer", "orcid": "0000-0001-6740-8797", "clpid": "Chao-Chu-Jennifer" }, { "family_name": "Schneider", "given_name": "Sandra", "clpid": "Schneider-Sandra" }, { "family_name": "Dzhindzhev", "given_name": "Nikola S.", "orcid": "0000-0001-9866-3600", "clpid": "Dzhindzhev-N-S" }, { "family_name": "Gottardo", "given_name": "Marco", "orcid": "0000-0001-8649-7799", "clpid": "Gottardo-Marco" }, { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "clpid": "Riparbelli-M-G" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Centrioles are required to assemble centrosomes for cell division and cilia for motility and signalling. New centrioles assemble perpendicularly to pre-existing ones in G1\u2013S and elongate throughout S and G2. Fully elongated daughter centrioles are converted into centrosomes during mitosis to be able to duplicate and organize pericentriolar material in the next cell cycle. Here we show that centriole-to-centrosome conversion requires sequential loading of Cep135, Ana1 (Cep295) and Asterless (Cep152) onto daughter centrioles during mitotic progression in both Drosophila melanogaster and human. This generates a molecular network spanning from the inner- to outermost parts of the centriole. Ana1 forms a molecular strut within the network, and its essential role can be substituted by an engineered fragment providing an alternative linkage between Asterless and Cep135. This conserved architectural framework is essential for loading Asterless or Cep152, the partner of the master regulator of centriole duplication, Plk4. Our study thus uncovers the molecular basis for centriole-to-centrosome conversion that renders daughter centrioles competent for motherhood.", "doi": "10.1038/ncb3274", "pmcid": "PMC4719191", "issn": "1465-7392", "publisher": "Nature Publishing Group", "publication": "Nature Cell Biology", "publication_date": "2016-01", "series_number": "1", "volume": "18", "issue": "1", "pages": "87-99" }, { "id": "authors:y5a9b-bsh53", "collection": "authors", "collection_id": "y5a9b-bsh53", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541252", "type": "article", "title": "Editorial bring in the new!", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The year 2015 has been a year for celebration when Royal Society publishing has marked the 350th anniversary of the first publication of its Philosophical Transactions, the world's first scientific journal that is still going strong (https://royalsociety.org/journals/publishing350/). \n\nOpen Biology, by contrast, is now an infant of a little over 4 years old but also thriving. Our aim with Open Biology was to establish an open access journal exploring biological systems at a cellular and molecular level of resolution, an area of biology that was underrepresented in the Society's existing journals. Above all, we wanted to have a journal run for cell and molecular biologists by practicing scientists that would bring first class articles to rapid publication without unnecessary rounds of review. We are making excellent progress towards this goal and Open Biology is publishing papers that are catching the attention of the community as evident from its rising impact factor (3.625 in 2012, 4.556 in 2013 and 5.784 in 2014\u2014just one measure of a variety of journal-based metrics used by the journal to assess impact http://rsob.royalsocietypublishing.org/citation-metrics).", "doi": "10.1098/rsob.150264", "pmcid": "PMC4736829", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2016-01", "series_number": "1", "volume": "6", "issue": "1", "pages": "Art. No. 150264" }, { "id": "authors:dz5vf-mz229", "collection": "authors", "collection_id": "dz5vf-mz229", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190405-170315456", "type": "article", "title": "Over-expression of Plk4 induces centrosome amplification, loss of primary cilia and associated tissue hyperplasia in the mouse", "author": [ { "family_name": "Coelho", "given_name": "Paula A.", "orcid": "0000-0003-0614-7575", "clpid": "Coelho-P-A" }, { "family_name": "Bury", "given_name": "Leah", "orcid": "0000-0002-6218-2837", "clpid": "Bury-L" }, { "family_name": "Shahbazi", "given_name": "Marta N.", "orcid": "0000-0002-1599-5747", "clpid": "Shahbazi-M-N" }, { "family_name": "Liakath-Ali", "given_name": "Kifayathullah", "clpid": "Liakath-Ali-K" }, { "family_name": "Tate", "given_name": "Peri H.", "clpid": "Tate-P-H" }, { "family_name": "Wormald", "given_name": "Sam", "clpid": "Wormald-S" }, { "family_name": "Hindley", "given_name": "Christopher J.", "clpid": "Hindley-C-J" }, { "family_name": "Huch", "given_name": "Meritxell", "clpid": "Huch-M" }, { "family_name": "Archer", "given_name": "Joy", "clpid": "Archer-J" }, { "family_name": "Skarnes", "given_name": "William C.", "clpid": "Skarnes-W-C" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "To address the long-known relationship between supernumerary centrosomes and cancer, we have generated a transgenic mouse that permits inducible expression of the master regulator of centriole duplication, Polo-like-kinase-4 (Plk4). Over-expression of Plk4 from this transgene advances the onset of tumour formation that occurs in the absence of the tumour suppressor p53. Plk4 over-expression also leads to hyperproliferation of cells in the pancreas and skin that is enhanced in a p53 null background. Pancreatic islets become enlarged following Plk4 over-expression as a result of equal expansion of \u03b1- and \u03b2-cells, which exhibit centrosome amplification. Mice overexpressing Plk4 develop grey hair due to a loss of differentiated melanocytes and bald patches of skin associated with a thickening of the epidermis. This reflects an increase in proliferating cells expressing keratin 5 in the basal epidermal layer and the expansion of these cells into suprabasal layers. Such cells also express keratin 6, a marker for hyperplasia. This is paralleled by a decreased expression of later differentiation markers, involucrin, filaggrin and loricrin. Proliferating cells showed an increase in centrosome number and a loss of primary cilia, events that were mirrored in primary cultures of keratinocytes established from these animals. We discuss how repeated duplication of centrioles appears to prevent the formation of basal bodies leading to loss of primary cilia, disruption of signalling and thereby aberrant differentiation of cells within the epidermis. The absence of p53 permits cells with increased centrosomes to continue dividing, thus setting up a neoplastic state of error prone mitoses, a prerequisite for cancer development.", "doi": "10.1098/rsob.150209", "pmcid": "PMC4703062", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2015-12", "series_number": "12", "volume": "5", "issue": "12", "pages": "Art. No. 150209" }, { "id": "authors:h6szj-p5e35", "collection": "authors", "collection_id": "h6szj-p5e35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353740", "type": "article", "title": "The Dawn of Aurora Kinase Research: From Fly Genetics to the Clinic", "author": [ { "family_name": "Carmena", "given_name": "Mar", "orcid": "0000-0002-2352-1066", "clpid": "Carmena-M" }, { "family_name": "Earnshaw", "given_name": "William C.", "orcid": "0000-0002-7191-0621", "clpid": "Earnshaw-W-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Aurora kinases comprise a family of highly conserved serine-threonine protein kinases that play a pivotal role in the regulation of cell cycle. Aurora kinases are not only involved in the control of multiple processes during cell division but also coordinate chromosomal and cytoskeletal events, contributing to the regulation of checkpoints and ensuring the smooth progression of the cell cycle. Because of their fundamental contribution to cell cycle regulation, Aurora kinases were originally identified in independent genetic screens designed to find genes involved in the regulation of cell division. The first aurora mutant was part of a collection of mutants isolated in C. Nusslein-Volhard's laboratory. This collection was screened in D. M. Glover's laboratory in search for mutations disrupting the centrosome cycle in embryos derived from homozygous mutant mothers. The mutants identified were given names related to the \"polar regions,\" and included not only aurora but also the equally famous polo. Ipl1, the only Aurora in yeast, was identified in a genetic screen looking for mutations that caused chromosome segregation defects. The discovery of a second Aurora-like kinase in mammals opened a new chapter in the research of Aurora kinases. The rat kinase AIM was found to be highly homologous to the fly and yeast proteins, but localized at the midzone and midbody and was proposed to have a role in cytokinesis. Homologs of the equatorial Aurora (Aurora B) were identified in metazoans ranging from flies to humans. Xenopus Aurora B was found to be in a complex with the chromosomal passenger INCENP, and both proteins were shown to be essential in flies for chromosome structure, segregation, central spindle formation and cytokinesis. Fifteen years on, Aurora kinase research is an active field of research. After the successful introduction of the first anti-mitotic agents in cancer therapy, both Auroras have become the focus of attention as targets for the development of new anti-cancer drugs. In this review we will aim to give a historical overview of the research on Aurora kinases, highlighting the most relevant milestones in the advance of the field.", "doi": "10.3389/fcell.2015.00073", "pmcid": "PMC4646952", "issn": "2296-634X", "publisher": "Frontiers Research Foundation", "publication": "Frontiers in Cell and Developmental Biology", "publication_date": "2015-11-17", "volume": "3", "pages": "Art. No. 73" }, { "id": "authors:9cta9-0r857", "collection": "authors", "collection_id": "9cta9-0r857", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114540212", "type": "article", "title": "DAPPER: a data-mining resource for protein-protein interactions", "author": [ { "family_name": "Haider", "given_name": "Syed", "orcid": "0000-0001-6685-5480", "clpid": "Haider-Syed" }, { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Z" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Ladak", "given_name": "Yaseen", "orcid": "0000-0002-8932-7207", "clpid": "Ladak-Y" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Kimata", "given_name": "Yuu", "orcid": "0000-0001-6223-1320", "clpid": "Kimata-Yuu" }, { "family_name": "Li\u00f3", "given_name": "Pietro", "orcid": "0000-0002-0540-5053", "clpid": "Li\u00f3-Pietro" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Background. The identification of interaction networks between proteins and complexes holds the promise of offering novel insights into the molecular mechanisms that regulate many biological processes. With increasing volumes of such datasets, especially in model organisms such as Drosophila melanogaster, there exists a pressing need for specialised tools, which can seamlessly collect, integrate and analyse these data. Here we describe a database coupled with a mining tool for protein-protein interactions (DAPPER), developed as a rich resource for studying multi-protein complexes in Drosophila melanogaster. \n\nResults. This proteomics database is compiled through mass spectrometric analyses of many protein complexes affinity purified from Drosophila tissues and cultured cells. The web access to DAPPER is provided via an accelerated version of BioMart software enabling data-mining through customised querying and output formats. The protein-protein interaction dataset is annotated with FlyBase identifiers, and further linked to the Ensembl database using BioMart's data-federation model, thereby enabling complex multi-dataset queries. DAPPER is open source, with all its contents and source code are freely available. \n\nConclusions. DAPPER offers an easy-to-navigate and extensible platform for real-time integration of diverse resources containing new and existing protein-protein interaction datasets of Drosophila melanogaster.", "doi": "10.1186/s13040-015-0063-3", "pmcid": "PMC4581157", "issn": "1756-0381", "publisher": "Springer Science and Business Media LLC", "publication": "BioData Mining", "publication_date": "2015-09-24", "volume": "8", "pages": "Art. no. 30" }, { "id": "authors:3txrh-2t313", "collection": "authors", "collection_id": "3txrh-2t313", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150624733", "type": "article", "title": "Establishment of Centromeric Chromatin by the CENP-A Assembly Factor CAL1 Requires FACT-Mediated Transcription", "author": [ { "family_name": "Chen", "given_name": "Chin-Chi", "clpid": "Chen-Chin-Chi" }, { "family_name": "Bowers", "given_name": "Sarion", "clpid": "Bowers-Sarion" }, { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Z" }, { "family_name": "Palladino", "given_name": "Jason", "clpid": "Palladino-Jason" }, { "family_name": "Trusiak", "given_name": "Sarah", "clpid": "Trusiak-Sarah" }, { "family_name": "Bettini", "given_name": "Emily", "clpid": "Bettini-Emily" }, { "family_name": "Rosin", "given_name": "Leah", "clpid": "Rosin-Leah" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "clpid": "Przewloka-M-R" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "O'Neill", "given_name": "Rachel\u00a0J.", "clpid": "O'Neill-Rachel-J" }, { "family_name": "Mellone", "given_name": "Barbara\u00a0G.", "clpid": "Mellone-B-G" } ], "abstract": "Centromeres are essential chromosomal structures that mediate accurate chromosome segregation during cell division. Centromeres are specified epigenetically by the heritable incorporation of the centromeric histone H3 variant CENP-A. While many of the primary factors that mediate centromeric deposition of CENP-A are known, the chromatin and DNA requirements of this process have remained elusive. Here, we uncover a role for transcription in Drosophila CENP-A deposition. Using an inducible ectopic centromere system that uncouples CENP-A deposition from endogenous centromere function and cell-cycle progression, we demonstrate that CENP-A assembly by its loading factor, CAL1, requires RNAPII-mediated transcription of the underlying DNA. This transcription depends on the CAL1 binding partner FACT, but not on CENP-A incorporation. Our work establishes RNAPII passage as a key step in chaperone-mediated CENP-A chromatin establishment and propagation.", "doi": "10.1016/j.devcel.2015.05.012", "pmcid": "PMC4495351", "issn": "1534-5807", "publisher": "Cell Press", "publication": "Developmental Cell", "publication_date": "2015-07-06", "series_number": "1", "volume": "34", "issue": "1", "pages": "73-84" }, { "id": "authors:majcj-1h778", "collection": "authors", "collection_id": "majcj-1h778", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163115453", "type": "article", "title": "The Pentameric Nucleoplasmin Fold Is Present in Drosophila FKBP39 and a Large Number of Chromatin-Related Proteins", "author": [ { "family_name": "Edlich-Muth", "given_name": "Christian", "orcid": "0000-0003-3942-7813", "clpid": "Edlich-Muth-C" }, { "family_name": "Artero", "given_name": "Jean-Baptiste", "clpid": "Artero-J-B" }, { "family_name": "Callow", "given_name": "Phil", "clpid": "Calow-P" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Watson", "given_name": "Aleksandra A.", "clpid": "Watson-A-A" }, { "family_name": "Zhang", "given_name": "Wei", "clpid": "Zhang-Wei" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Debski", "given_name": "Janusz", "orcid": "0000-0002-0171-7797", "clpid": "Debski-J" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-M" }, { "family_name": "Round", "given_name": "Adam R.", "orcid": "0000-0002-0723-8228", "clpid": "Round-A-R" }, { "family_name": "Forsyth", "given_name": "V. Trevor", "orcid": "0000-0003-0380-3477", "clpid": "Forsyth-V-T" }, { "family_name": "Laue", "given_name": "Ernest D.", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" } ], "abstract": "Nucleoplasmin is a histone chaperone that consists of a pentameric N-terminal domain and an unstructured C-terminal tail. The pentameric core domain, a doughnut-like structure with a central pore, is only found in the nucleoplasmin family. Here, we report the first structure of a nucleoplasmin-like domain (NPL) from the unrelated Drosophila protein, FKBP39, and we present evidence that this protein associates with chromatin. Furthermore, we show that two other chromatin proteins, Arabidopsis thaliana histone deacetylase type 2 (HD2) and Saccharomyces cerevisiae Fpr4, share the NPL fold and form pentamers, or a dimer of pentamers in the case of HD2. Thus, we propose a new family of proteins that share the pentameric nucleoplasmin-like NPL domain and are found in protists, fungi, plants and animals.", "doi": "10.1016/j.jmb.2015.03.010", "pmcid": "PMC4414354", "issn": "0022-2836", "publisher": "Elsevier", "publication": "Journal of Molecular Biology", "publication_date": "2015-05-22", "series_number": "10", "volume": "427", "issue": "10", "pages": "1949-1963" }, { "id": "authors:t1pgm-8q605", "collection": "authors", "collection_id": "t1pgm-8q605", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541473", "type": "article", "title": "The 350th anniversary of scientific publishing: van Leeuwenhoek, the most prolific author of the Philosophical Transactions of the Royal Society", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "This year marks the 350th anniversary of the launch of Philosophical Transactions of the Royal Society\u2014the world's first scientific journal. This innovative way of recording the Royal Society's business proved to be a model for scientific publishing as we now know it. It provided a means of reviewing scientific discovery, recording it, and most importantly provided a means for disseminating these findings. The history of the Society's publishing enterprises is truly fascinating and can be accessed at https://royalsociety.org/publishing350/.", "doi": "10.1098/rsob.150044", "pmcid": "PMC4422129", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2015-04", "series_number": "4", "volume": "5", "issue": "4", "pages": "Art. No. 150044" }, { "id": "authors:awk2p-1hd96", "collection": "authors", "collection_id": "awk2p-1hd96", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190405-170316054", "type": "article", "title": "Maternal-zygotic knockout reveals a critical role of Cdx2 in the morula to blastocyst transition", "author": [ { "family_name": "Jedrusik", "given_name": "Agnieszka", "clpid": "Jedrusik-A" }, { "family_name": "Cox", "given_name": "Andy", "clpid": "Cox-Andy" }, { "family_name": "Wicher", "given_name": "Krzysztof B.", "clpid": "Wicher-K-B" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "The first lineage segregation in the mouse embryo generates the inner cell mass (ICM), which gives rise to the pluripotent epiblast and therefore the future embryo, and the trophectoderm (TE), which will build the placenta. The TE lineage depends on the transcription factor Cdx2. However, when Cdx2 first starts to act remains unclear. Embryos with zygotic deletion of Cdx2 develop normally until the late blastocyst stage leading to the conclusion that Cdx2 is important for the maintenance but not specification of the TE. In contrast, down-regulation of Cdx2 transcripts from the early embryo stage results in defects in TE specification before the blastocyst stage. Here, to unambiguously address at which developmental stage Cdx2 becomes first required, we genetically deleted Cdx2 from the oocyte stage using a Zp3-Cre/loxP strategy. Careful assessment of a large cohort of Cdx2 maternal-zygotic null embryos, all individually filmed, examined and genotyped, reveals an earlier lethal phenotype than observed in Cdx2 zygotic null embryos that develop until the late blastocyst stage. The developmental failure of Cdx2 maternal-zygotic null embryos is associated with cell death and failure of TE specification, starting at the morula stage. These results indicate that Cdx2 is important for the correct specification of TE from the morula stage onwards and that both maternal and zygotic pools of Cdx2 are required for correct pre-implantation embryogenesis.", "doi": "10.1016/j.ydbio.2014.12.004", "pmcid": "PMC4319684", "issn": "0012-1606", "publisher": "Elsevier", "publication": "Developmental Biology", "publication_date": "2015-02-15", "series_number": "2", "volume": "398", "issue": "2", "pages": "147-152" }, { "id": "authors:ndbkq-62d43", "collection": "authors", "collection_id": "ndbkq-62d43", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-122117900", "type": "article", "title": "The Centrosome and Its Duplication Cycle", "author": [ { "family_name": "Fu", "given_name": "Jingyan", "orcid": "0000-0002-5896-8132", "clpid": "Fu-Jingyan" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-Iain-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The centrosome was discovered in the late 19th century when mitosis was first described. Long recognized as a key organelle of the spindle pole, its core component, the centriole, was realized more than 50 or so years later also to comprise the basal body of the cilium. Here, we chart the more recent acquisition of a molecular understanding of centrosome structure and function. The strategies for gaining such knowledge were quickly developed in the yeasts to decipher the structure and function of their distinctive spindle pole bodies. Only within the past decade have studies with model eukaryotes and cultured cells brought a similar degree of sophistication to our understanding of the centrosome duplication cycle and the multiple roles of this organelle and its component parts in cell division and signaling. Now as we begin to understand these functions in the context of development, the way is being opened up for studies of the roles of centrosomes in human disease.", "doi": "10.1101/cshperspect.a015800", "pmcid": "PMC4315929", "issn": "1943-0264", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Cold Spring Harbor Perspectives in Biology", "publication_date": "2015-02", "series_number": "2", "volume": "7", "issue": "2", "pages": "Art. No. a015800" }, { "id": "authors:1ppdh-gbq96", "collection": "authors", "collection_id": "1ppdh-gbq96", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170354831", "type": "article", "title": "Centromeric binding and activity of Protein Phosphatase 4", "author": [ { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Z" }, { "family_name": "Lefevre", "given_name": "Stephane", "clpid": "Lefevre-Stephane" }, { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Singleton", "given_name": "Martin R.", "clpid": "Singleton-M-R" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" } ], "abstract": "The cell division cycle requires tight coupling between protein phosphorylation and dephosphorylation. However, understanding the cell cycle roles of multimeric protein phosphatases has been limited by the lack of knowledge of how their diverse regulatory subunits target highly conserved catalytic subunits to their sites of action. Phosphoprotein phosphatase 4 (PP4) has been recently shown to participate in the regulation of cell cycle progression. We now find that the EVH1 domain of the regulatory subunit 3 of Drosophila PP4, Falafel (Flfl), directly interacts with the centromeric protein C (CENP-C). Unlike other EVH1 domains that interact with proline-rich ligands, the crystal structure of the Flfl amino-terminal EVH1 domain bound to a CENP-C peptide reveals a new target-recognition mode for the phosphatase subunit. We also show that binding of Flfl to CENP-C is required to bring PP4 activity to centromeres to maintain CENP-C and attached core kinetochore proteins at chromosomes during mitosis.", "doi": "10.1038/ncomms6894", "pmcid": "PMC4354016", "issn": "2041-1723", "publisher": "Nature Publishing Group", "publication": "Nature Communications", "publication_date": "2015-01-15", "volume": "6", "pages": "Art. No. 5894" }, { "id": "authors:31gpd-f4y21", "collection": "authors", "collection_id": "31gpd-f4y21", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150624931", "type": "article", "title": "Plk4 Phosphorylates Ana2 to Trigger Sas6 Recruitment and Procentriole Formation", "author": [ { "family_name": "Dzhindzhev", "given_name": "Nikola\u00a0S.", "clpid": "Dzhindzhev-N-S" }, { "family_name": "Tzolovsky", "given_name": "George", "clpid": "Tzolovsky-G" }, { "family_name": "Lipinszki", "given_name": "Zoltan", "orcid": "0000-0002-2067-0832", "clpid": "Lipinszki-Z" }, { "family_name": "Schneider", "given_name": "Sandra", "clpid": "Schneider-Sandra" }, { "family_name": "Lattao", "given_name": "Ramona", "orcid": "0000-0002-1725-0175", "clpid": "Lattao-Ramona" }, { "family_name": "Fu", "given_name": "Jingyan", "orcid": "0000-0002-5896-8132", "clpid": "Fu-Jingyan" }, { "family_name": "Debski", "given_name": "Janusz", "orcid": "0000-0002-0171-7797", "clpid": "Debski-J" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Centrioles are 9-fold symmetrical structures at the core of centrosomes and base of cilia whose dysfunction has been linked to a wide range of inherited diseases and cancer [1]. Their duplication is regulated by a protein kinase of conserved structure, the C. elegans ZYG-1 or its Polo-like kinase 4 (Plk4) counterpart in other organisms [2, 3, 4]. Although Plk4's centriolar partners and mechanisms that regulate its stability are known, its crucial substrates for centriole duplication have never been identified. Here we show that Drosophila Plk4 phosphorylates four conserved serines in the STAN motif of the core centriole protein Ana2 to enable it to bind and recruit its Sas6 partner. Ana2 and Sas6 normally load onto both mother and daughter centrioles immediately after their disengagement toward the end of mitosis to seed procentriole formation. Nonphosphorylatable Ana2 still localizes to the centriole but can no longer recruit Sas6 and centriole duplication fails. Thus, following centriole disengagement, recruitment of Ana2 and its phosphorylation by Plk4 are the earliest known events in centriole duplication to recruit Sas6 and thereby establish the architecture of the new procentriole engaged with its parent.", "doi": "10.1016/j.cub.2014.08.061", "pmcid": "PMC4229625", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2014-11-03", "series_number": "21", "volume": "24", "issue": "21", "pages": "2526-2532" }, { "id": "authors:p6r8g-f1h69", "collection": "authors", "collection_id": "p6r8g-f1h69", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170352671", "type": "article", "title": "Insight into the Architecture of the NuRD Complex: Structure of the RbAp48-MTA1 Subcomplex", "author": [ { "family_name": "Alqarni", "given_name": "Saad S. M.", "clpid": "Alqarni-S-S-M" }, { "family_name": "Murthy", "given_name": "Andal", "clpid": "Murthy-Andal" }, { "family_name": "Zhang", "given_name": "Wei", "clpid": "Zhang-Wei" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Silva", "given_name": "Ana P. G.", "clpid": "Silva-Ana-P-G" }, { "family_name": "Watson", "given_name": "Aleksandra A.", "clpid": "Watson-A-A" }, { "family_name": "Lejon", "given_name": "Sara", "clpid": "Lejon-Sara" }, { "family_name": "Pei", "given_name": "Xue Y.", "clpid": "Pei-Xue-Y" }, { "family_name": "Smits", "given_name": "Arne H.", "clpid": "Smits-Ame-H" }, { "family_name": "Kloet", "given_name": "Susan L.", "orcid": "0000-0001-9189-0640", "clpid": "Kloet-S-L" }, { "family_name": "Wang", "given_name": "Hongxin", "clpid": "Wang-Hongxin" }, { "family_name": "Shepherd", "given_name": "Nicholas E.", "orcid": "0000-0001-6234-4456", "clpid": "Shepherd-N-E" }, { "family_name": "Stokes", "given_name": "Philippa H.", "orcid": "0000-0002-2671-6280", "clpid": "Stokes-P-H" }, { "family_name": "Blobel", "given_name": "Gerd A.", "orcid": "0000-0002-0714-9612", "clpid": "Blobel-Gerd-A" }, { "family_name": "Vermeulen", "given_name": "Michiel", "orcid": "0000-0003-0836-6894", "clpid": "Vermeulen-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Mackay", "given_name": "Joel P.", "orcid": "0000-0001-7508-8033", "clpid": "Mackay-J-P" }, { "family_name": "Laue", "given_name": "Ernest D.", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" } ], "abstract": "The nucleosome remodeling and deacetylase (NuRD) complex is a widely conserved transcriptional co-regulator that harbors both nucleosome remodeling and histone deacetylase activities. It plays a critical role in the early stages of ES cell differentiation and the reprogramming of somatic to induced pluripotent stem cells. Abnormalities in several NuRD proteins are associated with cancer and aging. We have investigated the architecture of NuRD by determining the structure of a subcomplex comprising RbAp48 and MTA1. Surprisingly, RbAp48 recognizes MTA1 using the same site that it uses to bind histone H4, showing that assembly into NuRD modulates RbAp46/48 interactions with histones. Taken together with other results, our data show that the MTA proteins act as scaffolds for NuRD complex assembly. We further show that the RbAp48-MTA1 interaction is essential for the in vivo integration of RbAp46/48 into the NuRD complex.", "doi": "10.1074/jbc.m114.558940", "pmcid": "PMC4139204", "issn": "0021-9258", "publisher": "American Society for Biochemistry and Molecular Biology", "publication": "Journal of Biological Chemistry", "publication_date": "2014-08-08", "series_number": "32", "volume": "289", "issue": "32", "pages": "21844-21855" }, { "id": "authors:7065d-wzz65", "collection": "authors", "collection_id": "7065d-wzz65", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-122118067", "type": "article", "title": "Inhibition of Polo kinase by BI2536 affects centriole separation during Drosophila male meiosis", "author": [ { "family_name": "Riparbelli", "given_name": "Maria G.", "clpid": "Riparbelli-M-G" }, { "family_name": "Gottardo", "given_name": "Marco", "orcid": "0000-0001-8649-7799", "clpid": "Gottardo-Marco" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" } ], "abstract": "Pharmacological inhibition of Drosophila Polo kinase with BI2536 has allowed us to re-examine the requirements for Polo during Drosophila male gametogenesis. BI2536-treated spermatocytes persisted in a pro-metaphase state without dividing and had condensed chromosomes that did not separate. Centrosomes failed to recruit \u03b3-tubulin and centrosomin (Cnn) and were not associated with microtubule arrays that were abnormal and did not form proper bipolar spindles. Centrioles, which usually separate during the anaphase of the first meiosis, remained held together in a V-shaped configuration suggesting that Polo kinase regulates the proteolysis that breaks centriole linkage to ensure their disengagement. Despite these defects spermatid differentiation proceeds, leading to axoneme formation.", "doi": "10.4161/cc.29083", "pmcid": "PMC4111698", "issn": "1538-4101", "publisher": "Landes Bioscience", "publication": "Cell Cycle", "publication_date": "2014-07-01", "series_number": "13", "volume": "13", "issue": "13", "pages": "2064-2072" }, { "id": "authors:ja452-76x81", "collection": "authors", "collection_id": "ja452-76x81", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541570", "type": "article", "title": "Differing requirements for Augmin in male meiotic and mitotic spindle formation in Drosophila", "author": [ { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Animal cells divide using a microtubule-based, bipolar spindle. Both somatic, mitotic cells and sperm-producing male meiotic spermatocytes use centrosome-dependent and acentrosomal spindle-forming mechanisms. Here, we characterize the largely undefined, centrosome-independent spindle formation pathway used during male meiosis. Our live and fixed cell analyses of Drosophila spermatocytes reveal that acentrosomal microtubules are nucleated at kinetochores and in the vicinity of chromatin and that together these assemble into functional spindles. Mutational studies indicate that \u03b3-tubulin and its extra-centrosomal targeting complex, Augmin, are vital for this process. In addition, Augmin facilitates efficient spindle assembly in the presence of centrosomes. In contrast to the pronounced recruitment of Augmin on spindles in other cell types, the complex is absent from those of spermatocytes but does accumulate on kinetochores. Polo kinase facilitates this kinetochore recruitment while inhibiting Augmin's spindle association, and this in turn dictates \u03b3-tubulin distribution and spindle density. Polo's negative regulation of Augmin in male meiosis contrasts with its requirement in loading Augmin along mitotic spindles in somatic Drosophila cells. Together our data identify a novel mechanism of acentrosomal spindle formation in spermatocytes and reveal its divergence from that used in mitotic cells.", "doi": "10.1098/rsob.140047", "pmcid": "PMC4042853", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2014-05", "series_number": "5", "volume": "4", "issue": "5", "pages": "Art. No. 140047" }, { "id": "authors:g3jpk-7dm80", "collection": "authors", "collection_id": "g3jpk-7dm80", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190405-170316524", "type": "article", "title": "Spindle Formation in the Mouse Embryo Requires Plk4 in the Absence of Centrioles", "author": [ { "family_name": "Coelho", "given_name": "Paula\u00a0A.", "orcid": "0000-0003-0614-7575", "clpid": "Coelho-P-A" }, { "family_name": "Bury", "given_name": "Leah", "orcid": "0000-0002-6218-2837", "clpid": "Bury-L" }, { "family_name": "Sharif", "given_name": "Bedra", "clpid": "Sharif-B" }, { "family_name": "Riparbelli", "given_name": "Maria\u00a0G.", "clpid": "Riparbelli-M-G" }, { "family_name": "Fu", "given_name": "Jingyan", "clpid": "Fu-Jingyan" }, { "family_name": "Callaini", "given_name": "Giuliano", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David\u00a0M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "During the first five rounds of cell division in the mouse embryo, spindles assemble in the absence of centrioles. Spindle formation initiates around chromosomes, but the microtubule nucleating process remains unclear. Here we demonstrate that Plk4, a protein kinase known as a master regulator of centriole formation, is also essential for spindle assembly in the absence of centrioles. Depletion of maternal Plk4 prevents nucleation and growth of microtubules and results in monopolar spindle formation. This leads to cytokinesis failure and, consequently, developmental arrest. We show that Plk4 function depends on its kinase activity and its partner protein, Cep152. Moreover, tethering Cep152 to cellular membranes sequesters Plk4 and is sufficient to trigger spindle assembly from ectopic membranous sites. Thus, the Plk4-Cep152 complex has an unexpected role in promoting microtubule nucleation in the vicinity of chromosomes to mediate bipolar spindle formation in the absence of centrioles.", "doi": "10.1016/j.devcel.2013.09.029", "pmcid": "PMC3898710", "issn": "1534-5807", "publisher": "Cell Press", "publication": "Developmental Cell", "publication_date": "2013-12-09", "series_number": "5", "volume": "27", "issue": "5", "pages": "586-597" }, { "id": "authors:z3j33-bcv62", "collection": "authors", "collection_id": "z3j33-bcv62", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541678", "type": "article", "title": "Drosophila F-BAR protein Syndapin contributes to coupling the plasma membrane and contractile ring in cytokinesis", "author": [ { "family_name": "Takeda", "given_name": "Tetsuya", "orcid": "0000-0002-3183-6551", "clpid": "Takeda-Tetsuya" }, { "family_name": "Robinson", "given_name": "Iain M.", "clpid": "Robinson-I-M" }, { "family_name": "Savoian", "given_name": "Matthew M.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Griffiths", "given_name": "John R.", "orcid": "0000-0001-8288-5380", "clpid": "Griffiths-J-R" }, { "family_name": "Whetton", "given_name": "Anthony D.", "orcid": "0000-0002-1098-3878", "clpid": "Whetton-A-D" }, { "family_name": "McMahon", "given_name": "Harvey T.", "orcid": "0000-0001-8576-4541", "clpid": "McMahon-H-T" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Cytokinesis is a highly ordered cellular process driven by interactions between central spindle microtubules and the actomyosin contractile ring linked to the dynamic remodelling of the plasma membrane. The mechanisms responsible for reorganizing the plasma membrane at the cell equator and its coupling to the contractile ring in cytokinesis are poorly understood. We report here that Syndapin, a protein containing an F-BAR domain required for membrane curvature, contributes to the remodelling of the plasma membrane around the contractile ring for cytokinesis. Syndapin colocalizes with phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) at the cleavage furrow, where it directly interacts with a contractile ring component, Anillin. Accordingly, Anillin is mislocalized during cytokinesis in Syndapin mutants. Elevated or diminished expression of Syndapin leads to cytokinesis defects with abnormal cortical dynamics. The minimal segment of Syndapin, which is able to localize to the cleavage furrow and induce cytokinesis defects, is the F-BAR domain and its immediate C-terminal sequences. Phosphorylation of this region prevents this functional interaction, resulting in reduced ability of Syndapin to bind to and deform membranes. Thus, the dephosphorylated form of Syndapin mediates both remodelling of the plasma membrane and its proper coupling to the cytokinetic machinery.", "doi": "10.1098/rsob.130081", "pmcid": "PMC3758542", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2013-08", "series_number": "8", "volume": "3", "issue": "8", "pages": "Art. No. 130081" }, { "id": "authors:yfd0n-0ga25", "collection": "authors", "collection_id": "yfd0n-0ga25", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123358388", "type": "article", "title": "Esperanto for histones: CENP-A, not CenH3, is the centromeric histone H3 variant", "author": [ { "family_name": "Earnshaw", "given_name": "W. C.", "clpid": "Earnshaw-W-C" }, { "family_name": "Allshire", "given_name": "R. C." }, { "family_name": "Black", "given_name": "B. E." }, { "family_name": "Bloom", "given_name": "K." }, { "family_name": "Brinkley", "given_name": "B. R." }, { "family_name": "Brown", "given_name": "W." }, { "family_name": "Cheeseman", "given_name": "I. M." }, { "family_name": "Choo", "given_name": "K. H. A." }, { "family_name": "Copenhaver", "given_name": "G. P." }, { "family_name": "DeLuca", "given_name": "J. G." }, { "family_name": "Desai", "given_name": "A." }, { "family_name": "Diekmann", "given_name": "S." }, { "family_name": "Erhardt", "given_name": "S." }, { "family_name": "Fitzgerald-Hayes", "given_name": "M." }, { "family_name": "Foltz", "given_name": "D." }, { "family_name": "Fukagawa", "given_name": "T." }, { "family_name": "Gassmann", "given_name": "R." }, { "family_name": "Gerlich", "given_name": "D. W." }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Gorbsky", "given_name": "G. J." }, { "family_name": "Harrison", "given_name": "S. C." }, { "family_name": "Heun", "given_name": "P." }, { "family_name": "Hirota", "given_name": "T." }, { "family_name": "Jansen", "given_name": "L. E. T." }, { "family_name": "Karpen", "given_name": "G." }, { "family_name": "Kops", "given_name": "G. J. P. L." }, { "family_name": "Lampson", "given_name": "M. A." }, { "family_name": "Lens", "given_name": "S. M." }, { "family_name": "Losada", "given_name": "A." }, { "family_name": "Luger", "given_name": "K." }, { "family_name": "Maiato", "given_name": "H." }, { "family_name": "Maddox", "given_name": "P. S." }, { "family_name": "Margolis", "given_name": "R. L." }, { "family_name": "Masumoto", "given_name": "H." }, { "family_name": "McAinsh", "given_name": "A. D." }, { "family_name": "Mellone", "given_name": "B. G." }, { "family_name": "Meraldi", "given_name": "P." }, { "family_name": "Musacchio", "given_name": "A." }, { "family_name": "Oegema", "given_name": "K." }, { "family_name": "O'Neill", "given_name": "R. J." }, { "family_name": "Salmon", "given_name": "E. D." }, { "family_name": "Scott", "given_name": "K. C." }, { "family_name": "Straight", "given_name": "A. F." }, { "family_name": "Stukenberg", "given_name": "P. T." }, { "family_name": "Sullivan", "given_name": "B. A." }, { "family_name": "Sullivan", "given_name": "K. F." }, { "family_name": "Sunkel", "given_name": "C. E." }, { "family_name": "Swedlow", "given_name": "J. R." }, { "family_name": "Walczak", "given_name": "C. E." }, { "family_name": "Warburton", "given_name": "P. E." }, { "family_name": "Westermann", "given_name": "S." }, { "family_name": "Willard", "given_name": "H. F." }, { "family_name": "Wordeman", "given_name": "L." }, { "family_name": "Yanagida", "given_name": "M." }, { "family_name": "Yen", "given_name": "T. J." }, { "family_name": "Yoda", "given_name": "K." }, { "family_name": "Cleveland", "given_name": "D. W." } ], "abstract": "The first centromeric protein identified in any species was CENP-A, a divergent member of the histone H3 family that was recognised by autoantibodies from patients with scleroderma-spectrum disease. It has recently been suggested to rename this protein CenH3. Here, we argue that the original name should be maintained both because it is the basis of a long established nomenclature for centromere proteins and because it avoids confusion due to the presence of canonical histone H3 at centromeres.", "doi": "10.1007/s10577-013-9347-y", "pmcid": "PMC3627038", "issn": "0967-3849", "publisher": "Springer", "publication": "Chromosome Research", "publication_date": "2013-04", "series_number": "2", "volume": "21", "issue": "2", "pages": "101-106" }, { "id": "authors:6tvac-ctc84", "collection": "authors", "collection_id": "6tvac-ctc84", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541787", "type": "article", "title": "Structured illumination of the interface between centriole and peri-centriolar material", "author": [ { "family_name": "Fu", "given_name": "Jingyan", "orcid": "0000-0002-5896-8132", "clpid": "Fu-Jingyan" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The increase in centrosome size in mitosis was described over a century ago, and yet it is poorly understood how centrioles, which lie at the core of centrosomes, organize the pericentriolar material (PCM) in this process. Now, structured illumination microscopy reveals in Drosophila that, before clouds of PCM appear, its proteins are closely associated with interphase centrioles in two tube-like layers: an inner layer occupied by centriolar microtubules, Sas-4, Spd-2 and Polo kinase; and an outer layer comprising Pericentrin-like protein (Dplp), Asterless (Asl) and Plk4 kinase. Centrosomin (Cnn) and \u03b3-tubulin associate with this outer tube in G2 cells and, upon mitotic entry, Polo activity is required to recruit them together with Spd-2 into PCM clouds. Cnn is required for Spd-2 to expand into the PCM during this maturation process but can itself contribute to PCM independently of Spd-2. By contrast, the centrioles of spermatocytes elongate from a pre-existing proximal unit during the G2 preceding meiosis. Sas-4 is restricted to the microtubule-associated, inner cylinder and Dplp and Cnn to the outer cylinder of this proximal part. \u03b3-Tubulin and Asl associate with the outer cylinder and Spd-2 with the inner cylinder throughout the entire G2 centriole. Although they occupy different spatial compartments on the G2 centriole, Cnn, Spd-2 and \u03b3-tubulin become diminished at the centriole upon entry into meiosis to become part of PCM clouds.", "doi": "10.1098/rsob.120104", "pmcid": "PMC3438536", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2012-08", "series_number": "8", "volume": "2", "issue": "8", "pages": "Art. No. 120104" }, { "id": "authors:h4cph-7gc91", "collection": "authors", "collection_id": "h4cph-7gc91", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114541899", "type": "article", "title": "The chromosomal passenger complex controls the function of endosomal sorting complex required for transport-III Snf7 proteins during cytokinesis", "author": [ { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Montembault", "given_name": "Emilie", "orcid": "0000-0002-4850-3622", "clpid": "Montembault-E" }, { "family_name": "Takeda", "given_name": "Tetsuya", "orcid": "0000-0002-3183-6551", "clpid": "Takeda-Tetsuya" }, { "family_name": "Bassi", "given_name": "Zuni I.", "orcid": "0000-0003-4309-9656", "clpid": "Bassi-Z-I" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" } ], "abstract": "Cytokinesis controls the proper segregation of nuclear and cytoplasmic materials at the end of cell division. The chromosomal passenger complex (CPC) has been proposed to monitor the final separation of the two daughter cells at the end of cytokinesis in order to prevent cell abscission in the presence of DNA at the cleavage site, but the precise molecular basis for this is unclear. Recent studies indicate that abscission could be mediated by the assembly of filaments comprising components of the endosomal sorting complex required for transport-III (ESCRT-III). Here, we show that the CPC subunit Borealin interacts directly with the Snf7 components of ESCRT-III in both Drosophila and human cells. Moreover, we find that the CPC's catalytic subunit, Aurora B kinase, phosphorylates one of the three human Snf7 paralogues\u2014CHMP4C\u2014in its C-terminal tail, a region known to regulate its ability to form polymers and associate with membranes. Phosphorylation at these sites appears essential for CHMP4C function because their mutation leads to cytokinesis defects. We propose that CPC controls abscission timing through inhibition of ESCRT-III Snf7 polymerization and membrane association using two concurrent mechanisms: interaction of its Borealin component with Snf7 proteins and phosphorylation of CHMP4C by Aurora B.", "doi": "10.1098/rsob.120070", "pmcid": "PMC3376741", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2012-05", "series_number": "5", "volume": "2", "issue": "5", "pages": "Art. No. 120070" }, { "id": "authors:bgy5q-zzd29", "collection": "authors", "collection_id": "bgy5q-zzd29", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170354525", "type": "article", "title": "Drosophila Mgr, a Prefoldin subunit cooperating with von Hippel Lindau to regulate tubulin stability", "author": [ { "family_name": "Delgehyr", "given_name": "Nathalie", "clpid": "Delgehyr-N" }, { "family_name": "Wieland", "given_name": "Uta", "clpid": "Wieland-U" }, { "family_name": "Rangone", "given_name": "H\u00e9l\u00e8ne", "clpid": "Rangone-H" }, { "family_name": "Pinson", "given_name": "Xavier", "clpid": "Pinson-X" }, { "family_name": "Mao", "given_name": "Guojie", "clpid": "Mao-Guojie" }, { "family_name": "Dzhindzhev", "given_name": "Nikola S.", "orcid": "0000-0001-9866-3600", "clpid": "Dzhindzhev-N-S" }, { "family_name": "McLean", "given_name": "Doris", "clpid": "McLean-D-A" }, { "family_name": "Riparbelli", "given_name": "Maria G.", "clpid": "Riparbelli-M-G" }, { "family_name": "Llamazares", "given_name": "Salud", "clpid": "Llamazares-S" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Gonzalez", "given_name": "Cayetano", "clpid": "Gonzalez-Cayetano" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Mutations in Drosophila merry-go-round (mgr) have been known for over two decades to lead to circular mitotic figures and loss of meiotic spindle integrity. However, the identity of its gene product has remained undiscovered. We now show that mgr encodes the Prefoldin subunit counterpart of human von Hippel Lindau binding-protein 1. Depletion of Mgr from cultured cells also leads to formation of monopolar and abnormal spindles and centrosome loss. These phenotypes are associated with reductions of tubulin levels in both mgr flies and mgr RNAi-treated cultured cells. Moreover, mgr spindle defects can be phenocopied by depleting \u03b2-tubulin, suggesting Mgr function is required for tubulin stability. Instability of \u03b2-tubulin in the mgr larval brain is less pronounced than in either mgr testes or in cultured cells. However, expression of transgenic \u03b2-tubulin in the larval brain leads to increased tubulin instability, indicating that Prefoldin might only be required when tubulins are synthesized at high levels. Mgr interacts with Drosophila von Hippel Lindau protein (Vhl). Both proteins interact with unpolymerized tubulins, suggesting they cooperate in regulating tubulin functions. Accordingly, codepletion of Vhl with Mgr gives partial rescue of tubulin instability, monopolar spindle formation, and loss of centrosomes, leading us to propose a requirement for Vhl to promote degradation of incorrectly folded tubulin in the absence of functional Prefoldin. Thus, Vhl may play a pivotal role: promoting microtubule stabilization when tubulins are correctly folded by Prefoldin and tubulin destruction when they are not.", "doi": "10.1073/pnas.1108537109", "pmcid": "PMC3326472", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "2012-04-10", "series_number": "15", "volume": "109", "issue": "15", "pages": "5729-5734" }, { "id": "authors:t9a25-nvz92", "collection": "authors", "collection_id": "t9a25-nvz92", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150625099", "type": "article", "title": "Klp10A, a Microtubule-Depolymerizing Kinesin-13, Cooperates with CP110 to Control Drosophila Centriole Length", "author": [ { "family_name": "Delgehyr", "given_name": "Nathalie", "clpid": "Delgehyr-N" }, { "family_name": "Rangone", "given_name": "H\u00e9l\u00e8ne", "clpid": "Rangone-H" }, { "family_name": "Fu", "given_name": "Jingyan", "clpid": "Fu-Jingyan" }, { "family_name": "Mao", "given_name": "Guojie", "clpid": "Mao-Guojie" }, { "family_name": "Tom", "given_name": "Brian", "clpid": "Tom-B-D" }, { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "clpid": "Riparbelli-M-G" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Klp10A is a kinesin-13 of Drosophila melanogaster that depolymerizes cytoplasmic microtubules [1]. In interphase, it promotes microtubule catastrophe [2, 3, 4]; in mitosis, it contributes to anaphase chromosome movement by enabling tubulin flux [1, 5]. Here we show that Klp10A also acts as a microtubule depolymerase on centriolar microtubules to regulate centriole length. Thus, in both cultured cell lines and the testes, absence of Klp10A leads to longer centrioles that show incomplete 9-fold symmetry at their ends. These structures and associated pericentriolar material undergo fragmentation. We also show that in contrast to mammalian cells where depletion of CP110 leads to centriole elongation [6], in Drosophila cells it results in centriole length diminution that is overcome by codepletion of Klp10A to give longer centrioles than usual. We discuss how loss of centriole capping by CP110 might have different consequences for centriole length in mammalian [6, 7, 8] and insect cells and also relate these findings to the functional interactions between mammalian CP110 and another kinesin-13, Kif24, that in mammalian cells regulates cilium formation.", "doi": "10.1016/j.cub.2012.01.046", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2012-03-20", "series_number": "6", "volume": "22", "issue": "6", "pages": "502-509" }, { "id": "authors:axh1h-w0c98", "collection": "authors", "collection_id": "axh1h-w0c98", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114542017", "type": "article", "title": "The overlooked greatwall: a new perspective on mitotic control", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The role of the dual specificity protein phosphatase, Cdc25, in activating the cyclin-dependent kinase-cyclin B complex (Cdk1-CycB) by overcoming the inhibitory Wee1 kinase is a long-established principle for mitotic entry. Recently, however, evidence has emerged of a regulatory network that facilitates Cdk1-CycB activity by inhibiting the form of protein phosphatase 2A having a B55 regulatory subunit (PP2A-B55). Here, I review the genetic and biochemical evidence for Greatwall kinase and its substrate Endosulphine as the key components of this previously obscure regulatory network. Not only is the inhibition of PP2A-B55 by phospho-endosulphine required to prevent dephosphorylation of Cdk1-CycB substrates until mitotic exit, but it is also required to promote Cdc25 activity and inhibit Wee1 at mitotic entry. I discuss how these alternating states of preferential PP2A-B55 or Cdk1-CycB activity can have an impact upon the regulation of Polo kinase and its ability to bind different partner proteins as mitosis progresses.", "doi": "10.1098/rsob.120023", "pmcid": "PMC3382961", "issn": "2046-2441", "publisher": "Royal Society", "publication": "Open Biology", "publication_date": "2012-03", "series_number": "3", "volume": "2", "issue": "3", "pages": "Art. No. 120023" }, { "id": "authors:212gm-w2y28", "collection": "authors", "collection_id": "212gm-w2y28", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170354318", "type": "article", "title": "Spatiotemporal dynamics of Spc105 regulates the assembly of the Drosophila kinetochore", "author": [ { "family_name": "Venkei", "given_name": "Zsolt", "clpid": "Venkei-Z" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Ladak", "given_name": "Yaseen", "orcid": "0000-0002-8932-7207", "clpid": "Ladak-Y" }, { "family_name": "Albadri", "given_name": "Shahad", "clpid": "Albadri-Shahad" }, { "family_name": "Sossick", "given_name": "Alex", "clpid": "Sossick-A" }, { "family_name": "Juhasz", "given_name": "Gabor", "clpid": "Juhasz-G" }, { "family_name": "Nov\u00e1k", "given_name": "B\u00e9la", "clpid": "Nov\u00e1k-B\u00e9la" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The formation of kinetochores shortly before each cell division is a prerequisite for proper chromosome segregation. The synchronous mitoses of Drosophila syncytial embryos have provided an ideal in vivo system to follow kinetochore assembly kinetics and so address the question of how kinetochore formation is regulated. We found that the nuclear exclusion of the Spc105/KNL1 protein during interphase prevents precocious assembly of the Mis12 complex. The nuclear import of Spc105 in early prophase and its immediate association with the Mis12 complex on centromeres are thus the first steps in kinetochore assembly. The cumulative kinetochore levels of Spc105 and Mis12 complex then determine the rate of Ndc80 complex recruitment commencing only after nuclear envelope breakdown. The carboxy-terminal part of Spc105 directs its nuclear import and is sufficient for the assembly of all core kinetochore components and CENP-C, when localized ectopically to centrosomes. Super-resolution microscopy shows that carboxy-terminus of Spc105 lies at the junction of the Mis12 and Ndc80 complexes on stretched kinetochores. Our study thus indicates that physical accessibility of kinetochore components plays a crucial role in the regulation of Drosophila kinetochore assembly and leads us to a model in which Spc105 is a licensing factor for its onset.", "doi": "10.1098/rsob.110032", "pmcid": "PMC3352094", "issn": "2046-2441", "publisher": "The Royal Society", "publication": "Open Biology", "publication_date": "2012-02", "series_number": "2", "volume": "2", "issue": "2", "pages": "Art. No. 110032" }, { "id": "authors:h0d1z-jte43", "collection": "authors", "collection_id": "h0d1z-jte43", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170352108", "type": "article", "title": "The Chromosomal Passenger Complex Activates Polo Kinase at Centromeres", "author": [ { "family_name": "Carmena", "given_name": "Mar", "orcid": "0000-0002-2352-1066", "clpid": "Carmena-M" }, { "family_name": "Pinson", "given_name": "Xavier", "clpid": "Pinson-X" }, { "family_name": "Platani", "given_name": "Melpi", "orcid": "0000-0001-6408-4774", "clpid": "Platani-M" }, { "family_name": "Salloum", "given_name": "Zeina", "orcid": "0000-0003-4658-5000", "clpid": "Salloum-Z" }, { "family_name": "Xu", "given_name": "Zhenjie", "clpid": "Xu-Zhenjie" }, { "family_name": "Clark", "given_name": "Anthony", "clpid": "Clark-Anthony" }, { "family_name": "MacIsaac", "given_name": "Fiona", "clpid": "MacIsaac-F" }, { "family_name": "Ogawa", "given_name": "Hiromi", "orcid": "0000-0002-1972-1225", "clpid": "Ogawa-Hiromi" }, { "family_name": "Eggert", "given_name": "Ulrike", "orcid": "0000-0003-0932-5525", "clpid": "Eggert-U" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Earnshaw", "given_name": "William C.", "orcid": "0000-0002-7191-0621", "clpid": "Earnshaw-W-C" } ], "abstract": "The coordinated activities at centromeres of two key cell cycle kinases, Polo and Aurora B, are critical for ensuring that the two sister kinetochores of each chromosome are attached to microtubules from opposite spindle poles prior to chromosome segregation at anaphase. Initial attachments of chromosomes to the spindle involve random interactions between kinetochores and dynamic microtubules, and errors occur frequently during early stages of the process. The balance between microtubule binding and error correction (e.g., release of bound microtubules) requires the activities of Polo and Aurora B kinases, with Polo promoting stable attachments and Aurora B promoting detachment. Our study concerns the coordination of the activities of these two kinases in vivo. We show that INCENP, a key scaffolding subunit of the chromosomal passenger complex (CPC), which consists of Aurora B kinase, INCENP, Survivin, and Borealin/Dasra B, also interacts with Polo kinase in Drosophila cells. It was known that Aurora A/Bora activates Polo at centrosomes during late G2. However, the kinase that activates Polo on chromosomes for its critical functions at kinetochores was not known. We show here that Aurora B kinase phosphorylates Polo on its activation loop at the centromere in early mitosis. This phosphorylation requires both INCENP and Aurora B activity (but not Aurora A activity) and is critical for Polo function at kinetochores. Our results demonstrate clearly that Polo kinase is regulated differently at centrosomes and centromeres and suggest that INCENP acts as a platform for kinase crosstalk at the centromere. This crosstalk may enable Polo and Aurora B to achieve a balance wherein microtubule mis-attachments are corrected, but proper attachments are stabilized allowing proper chromosome segregation.", "doi": "10.1371/journal.pbio.1001250", "pmcid": "PMC3265468", "issn": "1545-7885", "publisher": "Public Library of Science", "publication": "PLoS Biology", "publication_date": "2012-01-24", "series_number": "1", "volume": "10", "issue": "1", "pages": "Art. No. e1001250" }, { "id": "authors:c3ppg-c7a91", "collection": "authors", "collection_id": "c3ppg-c7a91", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170352315", "type": "article", "title": "Sticky/Citron kinase maintains proper RhoA localization at the cleavage site during cytokinesis", "author": [ { "family_name": "Bassi", "given_name": "Zuni I.", "orcid": "0000-0003-4309-9656", "clpid": "Bassi-Z-I" }, { "family_name": "Verbrugghe", "given_name": "Koen J.", "clpid": "Verbrugghe-K-J" }, { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Gregory", "given_name": "Stephen", "orcid": "0000-0002-0046-5815", "clpid": "Gregory-Stephen" }, { "family_name": "Montembault", "given_name": "Emilie", "orcid": "0000-0002-4850-3622", "clpid": "Montembault-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" } ], "abstract": "In many organisms, the small guanosine triphosphatase RhoA controls assembly and contraction of the actomyosin ring during cytokinesis by activating different effectors. Although the role of some RhoA effectors like formins and Rho kinase is reasonably understood, the functions of another putative effector, Citron kinase (CIT-K), are still debated. In this paper, we show that, contrary to previous models, the Drosophila melanogaster CIT-K orthologue Sticky (Sti) does not require interaction with RhoA to localize to the cleavage site. Instead, RhoA fails to form a compact ring in late cytokinesis after Sti depletion, and this function requires Sti kinase activity. Moreover, we found that the Sti Citron-Nik1 homology domain interacts with RhoA regardless of its status, indicating that Sti is not a canonical RhoA effector. Finally, Sti depletion caused an increase of phosphorylated myosin regulatory light chain at the cleavage site in late cytokinesis. We propose that Sti/CIT-K maintains correct RhoA localization at the cleavage site, which is necessary for proper RhoA activity and contractile ring dynamics.", "doi": "10.1083/jcb.201105136", "pmcid": "PMC3257531", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2011-11-14", "series_number": "4", "volume": "195", "issue": "4", "pages": "595-603" }, { "id": "authors:0n5zx-1sw97", "collection": "authors", "collection_id": "0n5zx-1sw97", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123358587", "type": "article", "title": "Rab5 GTPase controls chromosome alignment through Lamin disassembly and relocation of the NuMA-like protein Mud to the poles during mitosis", "author": [ { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The small GTPase Rab5 is a conserved regulator of membrane trafficking; it regulates the formation of early endosomes, their transport along microtubules, and the fusion to the target organelles. Although several members of the endocytic pathway were recently implicated in spindle organization, it is unclear whether Rab5 has any role during mitosis. Here, we describe that Rab5 is required for proper chromosome alignment during Drosophila mitoses. We also found that Rab5 associated in vivo with nuclear Lamin and mushroom body defect (Mud), the Drosophila counterpart of nuclear mitotic apparatus protein (NuMA). Consistent with this finding, Rab5 was required for the disassembly of the nuclear envelope at mitotic entry and the accumulation of Mud at the spindle poles. Furthermore, Mud depletion caused chromosome misalignment defects that resembled the defects of Rab5 RNAi cells, and double-knockdown experiments indicated that the two proteins function in a linear pathway. Our results indicate a role for Rab5 in mitosis and reinforce the emerging view of the contributions made by cell membrane dynamics to spindle function.", "doi": "10.1073/pnas.1103720108", "pmcid": "PMC3198372", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "2011-10-18", "series_number": "42", "volume": "108", "issue": "42", "pages": "17343-17348" }, { "id": "authors:xyxfh-tzp92", "collection": "authors", "collection_id": "xyxfh-tzp92", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110829-104551403", "type": "article", "title": "Role for casein kinase 1 in the phosphorylation of Claspin on critical residues necessary for the activation of Chk1", "author": [ { "family_name": "Meng", "given_name": "Zheng", "clpid": "Meng-Zheng" }, { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Dunphy", "given_name": "William G.", "orcid": "0000-0001-7598-8939", "clpid": "Dunphy-W-G" } ], "abstract": "The mediator protein Claspin is critical for the activation of the checkpoint kinase Chk1 during checkpoint responses to stalled replication forks. This function involves the Chk1-activating domain (CKAD) of Claspin, which undergoes phosphorylation on multiple conserved sites. These phosphorylations promote binding of Chk1 to Claspin and ensuing activation of Chk1 by ATR. However, despite the importance of this regulatory process, the kinase responsible for these phosphorylations has remained unknown. By using a multifaceted approach, we have found that casein kinase 1 gamma 1 (CK1\u03b31) carries out this function. CK1\u03b31 phosphorylates the CKAD of Claspin efficiently in vitro, and depletion of CK1\u03b31 from human cells by small interfering RNA (siRNA) results in dramatically diminished phosphorylation of Claspin. Consequently, the siRNA-treated cells display impaired activation of Chk1 and resultant checkpoint defects. These results indicate that CK1\u03b31 is a novel component of checkpoint responses that controls the interaction of a key checkpoint effector kinase with its cognate mediator protein.", "doi": "10.1091/mbc.E11-01-0048", "pmcid": "PMC3154880", "issn": "1059-1524", "publisher": "American Society for Cell Biology", "publication": "Molecular Biology of the Cell", "publication_date": "2011-08-15", "series_number": "16", "volume": "22", "issue": "16", "pages": "2834-2847" }, { "id": "authors:50q3w-m0656", "collection": "authors", "collection_id": "50q3w-m0656", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351887", "type": "article", "title": "Suppression of Scant Identifies Endos as a Substrate of Greatwall Kinase and a Negative Regulator of Protein Phosphatase 2A in Mitosis", "author": [ { "family_name": "Rangone", "given_name": "H\u00e9l\u00e8ne", "clpid": "Rangone-H" }, { "family_name": "Wegel", "given_name": "Eva", "clpid": "Wegel-E" }, { "family_name": "Gatt", "given_name": "Melanie K.", "clpid": "Gatt-M-K" }, { "family_name": "Yeung", "given_name": "Eirene", "clpid": "Yeung-Eirene" }, { "family_name": "Flowers", "given_name": "Alexander", "clpid": "Flowers-Alexander" }, { "family_name": "Debski", "given_name": "Janusz", "orcid": "0000-0002-0171-7797", "clpid": "Debski-J" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-M" }, { "family_name": "Janssens", "given_name": "Veerle", "orcid": "0000-0002-6772-8448", "clpid": "Janssens-Veerle" }, { "family_name": "Carpenter", "given_name": "Adelaide T. C.", "clpid": "Carpenter-A-T-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Protein phosphatase 2A (PP2A) plays a major role in dephosphorylating the targets of the major mitotic kinase Cdk1 at mitotic exit, yet how it is regulated in mitotic progression is poorly understood. Here we show that mutations in either the catalytic or regulatory twins/B55 subunit of PP2A act as enhancers of gwl^(Scant), a gain-of-function allele of the Greatwall kinase gene that leads to embryonic lethality in Drosophila when the maternal dosage of the mitotic kinase Polo is reduced. We also show that heterozygous mutant endos alleles suppress heterozygous gwl^(Scant); many more embryos survive. Furthermore, heterozygous PP2A mutations make females heterozygous for the strong mutation polo\u00b9\u00b9 partially sterile, even in the absence of gwl^(Scant). Heterozygosity for an endos mutation suppresses this PP2A/polo\u00b9\u00b9 sterility. Homozygous mutation or knockdown of endos leads to phenotypes suggestive of defects in maintaining the mitotic state. In accord with the genetic interactions shown by the gwl^(Scant) dominant mutant, the mitotic defects of Endos knockdown in cultured cells can be suppressed by knockdown of either the catalytic or the Twins/B55 regulatory subunits of PP2A but not by the other three regulatory B subunits of Drosophila PP2A. Greatwall phosphorylates Endos at a single site, Ser68, and this is essential for Endos function. Together these interactions suggest that Greatwall and Endos act to promote the inactivation of PP2A-Twins/B55 in Drosophila. We discuss the involvement of Polo kinase in such a regulatory loop.", "doi": "10.1371/journal.pgen.1002225", "pmcid": "PMC3154957", "issn": "1553-7404", "publisher": "Public Library of Science", "publication": "PLOS Genetics", "publication_date": "2011-08-11", "series_number": "8", "volume": "7", "issue": "8", "pages": "Art. No. e1002225" }, { "id": "authors:09640-vzx76", "collection": "authors", "collection_id": "09640-vzx76", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150625212", "type": "article", "title": "CENP-C Is a Structural Platform for Kinetochore Assembly", "author": [ { "family_name": "Przewloka", "given_name": "Marcin\u00a0R.", "clpid": "Przewloka-M-R" }, { "family_name": "Venkei", "given_name": "Zsolt", "clpid": "Venkei-Z" }, { "family_name": "Bolanos-Garcia", "given_name": "Victor\u00a0M.", "clpid": "Bolanos-Garcia-V-M" }, { "family_name": "Debski", "given_name": "Janusz", "orcid": "0000-0002-0171-7797", "clpid": "Debski-J" }, { "family_name": "Dadlez", "given_name": "Michal", "orcid": "0000-0001-8811-5176", "clpid": "Dadlez-M" }, { "family_name": "Glover", "given_name": "David", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Centromeres provide a region of chromatin upon which kinetochores are assembled in mitosis [1, 2]. Centromeric protein C (CENP-C) is a core component of this centromeric chromatin [3, 4] that, when depleted, prevents the proper formation of both centromeres and kinetochores [5, 6, 7, 8, 9, 10]. CENP-C localizes to centromeres throughout the cell cycle via its C-terminal part [6, 8], whereas its N-terminal part appears necessary for recruitment of some but not all components of the Mis12 complex of the kinetochore [8]. We now find that all kinetochore proteins belonging to the KMN (KNL1/Spc105, the Mis12 complex, and the Ndc80 complex) network [1] bind to the N-terminal part of Drosophila CENP-C. Moreover, we show that the Mis12 complex component Nnf1 interacts directly with CENP-C in vitro. To test whether CENP-C's N-terminal part was sufficient to recruit KMN proteins, we targeted it to the centrosome by fusing it to a domain of Plk4 kinase [11]. The Mis12 and Ndc80 complexes and Spc105 protein were then all recruited to centrosomes at the expense of centromeres, leading to mitotic abnormalities typical of cells with defective kinetochores. Thus, the N-terminal part of Drosophila CENP-C is sufficient to recruit core kinetochore components and acts as the principal linkage between centromere and kinetochore during mitosis.", "doi": "10.1016/j.cub.2011.02.005", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2011-03-08", "series_number": "5", "volume": "21", "issue": "5", "pages": "399-405" }, { "id": "authors:0rmns-fvm37", "collection": "authors", "collection_id": "0rmns-fvm37", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150625497", "type": "article", "title": "Drosophila Mis12 Complex Acts as a Single Functional Unit Essential for Anaphase Chromosome Movement and a Robust Spindle Assembly Checkpoint", "author": [ { "family_name": "Venkei", "given_name": "Zsolt", "clpid": "Venkei-Z" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The kinetochore is a dynamic multiprotein complex assembled at the centromere in mitosis. Exactly how the structure of the kinetochore changes during mitosis and how its individual components contribute to chromosome segregation is largely unknown. Here we have focused on the contribution of the Mis12 complex to kinetochore assembly and function throughout mitosis in Drosophila. We show that despite the sequential kinetochore recruitment of Mis12 complex subunits Mis12 and Nsl1, the complex acts as a single functional unit. mis12 and nsl1 mutants show strikingly similar developmental and mitotic defects in which chromosomes are able to congress at metaphase, but their anaphase movement is strongly affected. While kinetochore association of Ndc80 absolutely depends on both Mis12 and Nsl1, BubR1 localization shows only partial dependency. In the presence of residual centromeric BubR1 the checkpoint still responds to microtubule depolymerization but is significantly weaker. These observations point to a complexity of the checkpoint response that may reflect subpopulations of BubR1 associated with residual kinetochore components, the core centromere, or elsewhere in the cell. Importantly our results indicate that core structural elements of the inner plate of the kinetochore have a greater contribution to faithful chromosome segregation in anaphase than in earlier stages of mitosis.", "doi": "10.1534/genetics.110.119628", "pmcid": "PMC3018309", "issn": "0016-6731", "publisher": "Genetics Society of America", "publication": "Genetics", "publication_date": "2011-01", "series_number": "1", "volume": "187", "issue": "1", "pages": "131-140" }, { "id": "authors:tjkg0-jj952", "collection": "authors", "collection_id": "tjkg0-jj952", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170352414", "type": "article", "title": "Nessun Dorma, a novel centralspindlin partner, is required for cytokinesis in Drosophila spermatocytes", "author": [ { "family_name": "Montembault", "given_name": "Emilie", "orcid": "0000-0002-4850-3622", "clpid": "Montembault-E" }, { "family_name": "Zhang", "given_name": "Wei", "clpid": "Zhang-Wei" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Sevin", "given_name": "Emeric W.", "clpid": "Sevin-E-W" }, { "family_name": "Laue", "given_name": "Ernest D.", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" } ], "abstract": "Cytokinesis, the final step of cell division, usually ends with the abscission of the two daughter cells. In some tissues, however, daughter cells never completely separate and remain interconnected by intercellular bridges or ring canals. In this paper, we report the identification and analysis of a novel ring canal component, Nessun Dorma (Nesd), isolated as an evolutionarily conserved partner of the centralspindlin complex, a key regulator of cytokinesis. Nesd contains a pectin lyase\u2013like domain found in proteins that bind to polysaccharides, and we present evidence that it has high affinity for \u03b2-galactosides in vitro. Moreover, nesd is an essential gene in Drosophila melanogaster, in which it is required for completion of cytokinesis during male meiosis and possibly in female germline cells. Our findings indicate that Nesd is a novel carbohydrate-binding protein that functions together with centralspindlin in late cytokinesis, thus highlighting the importance of glycosylation in this process.", "doi": "10.1083/jcb.201007060", "pmcid": "PMC3010078", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2010-12-27", "series_number": "7", "volume": "191", "issue": "7", "pages": "1351-1365" }, { "id": "authors:10j6w-4we11", "collection": "authors", "collection_id": "10j6w-4we11", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190417-163114460", "type": "article", "title": "The chromosome passenger complex is required for fidelity of chromosome transmission and cytokinesis in meiosis of mouse oocytes", "author": [ { "family_name": "Sharif", "given_name": "Bedra", "clpid": "Sharif-B" }, { "family_name": "Na", "given_name": "Jie", "clpid": "Na-Jie" }, { "family_name": "Lykke-Hartmann", "given_name": "Karin", "clpid": "Lykke-Hartmann-K" }, { "family_name": "McLaughlin", "given_name": "Stephen H.", "clpid": "McLaughlin-S-H" }, { "family_name": "Laue", "given_name": "Ernest", "clpid": "Laue-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "The existence of two forms of the chromosome passenger complex (CPC) in the mammalian oocyte has meant that its role in female meiosis has remained unclear. Here we use loss- and gain-of function approaches to assess the meiotic functions of one of the shared components of these complexes, INCENP, and of the variable kinase subunits, Aurora B or Aurora C. We show that either the depletion of INCENP or the combined inhibition of Aurora kinases B and C activates the anaphase-promoting complex or cyclosome (APC/C) before chromosomes have properly congressed in meiosis I and also prevents cytokinesis and hence extrusion of the first polar body. Overexpression of Aurora C also advances APC/C activation and results in cytokinesis failure in a high proportion of oocytes, indicative of a dominant effect on CPC function. Together, this points to roles for the meiotic CPC in functions similar to the mitotic roles of the complex: correcting chromosome attachment to microtubules, facilitating the spindle-assembly checkpoint (SAC) function and enabling cytokinesis. Surprisingly, overexpression of Aurora B leads to a failure of APC/C activation, stabilization of securin and consequently a failure of chiasmate chromosomes to resolve \u2013 a dominant phenotype that is completely suppressed by depletion of INCENP. Taken together with the differential distribution of Aurora proteins B and C on chiasmate chromosomes, this points to differential functions of the two forms of CPC in regulating the separation of homologous chromosomes in meiosis I.", "doi": "10.1242/jcs.067447", "pmcid": "PMC2995614", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2010-12-15", "series_number": "24", "volume": "123", "issue": "24", "pages": "4292-4300" }, { "id": "authors:bm952-52k16", "collection": "authors", "collection_id": "bm952-52k16", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-153617371", "type": "article", "title": "Human ASPM participates in spindle organisation, spindle orientation and cytokinesis", "author": [ { "family_name": "Higgins", "given_name": "Julie", "clpid": "Higgins-Julie" }, { "family_name": "Midgley", "given_name": "Carol", "clpid": "Midgley-Carol-A" }, { "family_name": "Bergh", "given_name": "Anna-Maria", "clpid": "Bergh-Anna-Maria" }, { "family_name": "Bell", "given_name": "Sandra M.", "clpid": "Bell-Sandra-M" }, { "family_name": "Askham", "given_name": "Jonathan M.", "clpid": "Askham-J-M" }, { "family_name": "Roberts", "given_name": "Emma", "clpid": "Roberts-Emma" }, { "family_name": "Binns", "given_name": "Ruth K.", "clpid": "Binns-Ruth-K" }, { "family_name": "Sharif", "given_name": "Saghira M.", "clpid": "Sharif-Sahgira-M" }, { "family_name": "Bennett", "given_name": "Christopher", "clpid": "Bennett-Christopher" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Woods", "given_name": "C. Geoffrey", "clpid": "Woods-C-G" }, { "family_name": "Morrison", "given_name": "Ewan E.", "clpid": "Morrison-Ewan-E" }, { "family_name": "Bond", "given_name": "Jacquelyn", "clpid": "Bond-Jacquelyn" } ], "abstract": "Background. Mutations in the A bnormal Sp indle M icrocephaly related gene (ASPM) are the commonest cause of autosomal recessive primary microcephaly (MCPH) a disorder characterised by a small brain and associated mental retardation. ASPM encodes a mitotic spindle pole associated protein. It is suggested that the MCPH phenotype arises from proliferation defects in neural progenitor cells (NPC). \n\nResults. We show that ASPM is a microtubule minus end-associated protein that is recruited in a microtubule-dependent manner to the pericentriolar matrix (PCM) at the spindle poles during mitosis. ASPM siRNA reduces ASPM protein at the spindle poles in cultured U2OS cells and severely perturbs a number of aspects of mitosis, including the orientation of the mitotic spindle, the main determinant of developmental asymmetrical cell division. The majority of ASPM depleted mitotic cells fail to complete cytokinesis. In MCPH patient fibroblasts we show that a pathogenic ASPM splice site mutation results in the expression of a novel variant protein lacking a tripeptide motif, a minimal alteration that correlates with a dramatic decrease in ASPM spindle pole localisation. Moreover, expression of dominant-negative ASPM C-terminal fragments cause severe spindle assembly defects and cytokinesis failure in cultured cells. \n\nConclusions. These observations indicate that ASPM participates in spindle organisation, spindle positioning and cytokinesis in all dividing cells and that the extreme C-terminus of the protein is required for ASPM localisation and function. Our data supports the hypothesis that the MCPH phenotype caused by ASPM mutation is a consequence of mitotic aberrations during neurogenesis. We propose the effects of ASPM mutation are tolerated in somatic cells but have profound consequences for the symmetrical division of NPCs, due to the unusual morphology of these cells. This antagonises the early expansion of the progenitor pool that underpins cortical neurogenesis, causing the MCPH phenotype.", "doi": "10.1186/1471-2121-11-85", "pmcid": "PMC2988714", "issn": "1471-2121", "publisher": "Springer Science and Business Media LLC", "publication": "BMC Cell Biology", "publication_date": "2010-11-02", "volume": "11", "pages": "Art. No. 85" }, { "id": "authors:5kz7e-c3749", "collection": "authors", "collection_id": "5kz7e-c3749", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150625316", "type": "article", "title": "Discovery and Characterization of 2-Anilino-4- (Thiazol-5-yl)Pyrimidine Transcriptional CDK Inhibitors as Anticancer Agents", "author": [ { "family_name": "Wang", "given_name": "Shudong", "clpid": "Wang-Shudong" }, { "family_name": "Griffiths", "given_name": "Gary", "clpid": "Griffiths-Gary" }, { "family_name": "Midgley", "given_name": "Carol A.", "clpid": "Midgley-Carol-A" }, { "family_name": "Barnett", "given_name": "Anna L.", "clpid": "Barnett-Anna-L" }, { "family_name": "Cooper", "given_name": "Michael", "clpid": "Cooper-Michael" }, { "family_name": "Grabarek", "given_name": "Joanna", "clpid": "Grabarek-J-B" }, { "family_name": "Ingram", "given_name": "Laura", "clpid": "Ingram-Laura" }, { "family_name": "Jackson", "given_name": "Wayne", "clpid": "Jackson-Wayne" }, { "family_name": "Kontopidis", "given_name": "George", "clpid": "Kontopidis-George" }, { "family_name": "McClue", "given_name": "Steven J.", "clpid": "McClue-Steven-J" }, { "family_name": "McInnes", "given_name": "Campbell", "clpid": "McInnes-Campbell" }, { "family_name": "McLachlan", "given_name": "Janice", "clpid": "McLachlan-Janice" }, { "family_name": "Meades", "given_name": "Christopher", "clpid": "Meades-Christopher" }, { "family_name": "Mezna", "given_name": "Mokdad", "clpid": "Mezna-Mokdad" }, { "family_name": "Stuart", "given_name": "Iain", "clpid": "Stuart-Iain" }, { "family_name": "Thomas", "given_name": "Mark P.", "clpid": "Thomas-Mark-P" }, { "family_name": "Zheleva", "given_name": "Daniella I.", "clpid": "Zheleva-D-I" }, { "family_name": "Lane", "given_name": "David P.", "clpid": "Lane-D-P" }, { "family_name": "Jackson", "given_name": "Robert C.", "clpid": "Jackson-Robert-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Blake", "given_name": "David G.", "clpid": "Blake-David-G" }, { "family_name": "Fischer", "given_name": "Peter M.", "clpid": "Fischer-Peter-M" } ], "abstract": "The main difficulty in the development of ATP antagonist kinase inhibitors is target specificity, since the ATP-binding motif is present in many proteins. We introduce a strategy that has allowed us to identify compounds from a kinase inhibitor library that block the cyclin-dependent kinases responsible for regulating transcription, i.e., CDK7 and especially CDK9. The screening cascade employs cellular phenotypic assays based on mitotic index and nuclear p53 protein accumulation. This permitted us to classify compounds into transcriptional, cell cycle, and mitotic inhibitor groups. We describe the characterization of the transcriptional inhibitor class in terms of kinase inhibition profile, cellular mode of action, and selectivity for transformed cells. A structural selectivity rationale was used to optimize potency and biopharmaceutical properties and led to the development of a transcriptional inhibitor, 3,4-dimethyl-5-[2-(4-piperazin-1-yl-phenylamino)-pyrimidin-4-yl]-3H-thiazol-2-one, with anticancer activity in animal models.", "doi": "10.1016/j.chembiol.2010.07.016", "issn": "1074-5521", "publisher": "Cell Press", "publication": "Chemistry and Biology", "publication_date": "2010-10-29", "series_number": "10", "volume": "17", "issue": "10", "pages": "1111-1121" }, { "id": "authors:twzj1-1kg43", "collection": "authors", "collection_id": "twzj1-1kg43", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-122118207", "type": "article", "title": "The RNA binding protein Larp1 regulates cell division, apoptosis and cell migration", "author": [ { "family_name": "Burrows", "given_name": "Carla", "clpid": "Burrows-Carla" }, { "family_name": "Abd Latip", "given_name": "Normala", "clpid": "Abd-Latip-Normala" }, { "family_name": "Lam", "given_name": "Sarah-Jane", "clpid": "Lam-Sarah-Jane" }, { "family_name": "Carpenter", "given_name": "Lee", "clpid": "Carpenter-Lee" }, { "family_name": "Sawicka", "given_name": "Kirsty", "clpid": "Sawicka-Kirsty" }, { "family_name": "Tzolovsky", "given_name": "George", "clpid": "Tzolovsky-G" }, { "family_name": "Gabra", "given_name": "Hani", "clpid": "Gabra-Hani" }, { "family_name": "Bushell", "given_name": "Martin", "clpid": "Bushell-Martin" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Willis", "given_name": "Anne E.", "clpid": "Willis-Anne-E" }, { "family_name": "Blagden", "given_name": "Sarah P.", "clpid": "Blagden-S-P" } ], "abstract": "The RNA binding protein Larp1 was originally shown to be involved in spermatogenesis, embryogenesis and cell-cycle progression in Drosophila. Our data show that mammalian Larp1 is found in a complex with poly A binding protein and eukaryote initiation factor 4E and is associated with 60S and 80S ribosomal subunits. A reduction in Larp1 expression by siRNA inhibits global protein synthesis rates and results in mitotic arrest and delayed cell migration. Consistent with these data we show that Larp1 protein is present at the leading edge of migrating cells and interacts directly with cytoskeletal components. Taken together, these data suggest a role for Larp1 in facilitating the synthesis of proteins required for cellular remodelling and migration.", "doi": "10.1093/nar/gkq294", "pmcid": "PMC2938220", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "2010-09-01", "series_number": "16", "volume": "38", "issue": "16", "pages": "5542-5553" }, { "id": "authors:brb68-hbt19", "collection": "authors", "collection_id": "brb68-hbt19", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150625661", "type": "article", "title": "SIK2 Is a Centrosome Kinase Required for Bipolar Mitotic Spindle Formation that Provides a Potential Target for Therapy in Ovarian Cancer", "author": [ { "family_name": "Ahmed", "given_name": "Ahmed Ashour", "clpid": "Ahmed-Ahmed Ashour" }, { "family_name": "Lu", "given_name": "Zhen", "clpid": "Lu-Zhen" }, { "family_name": "Jennings", "given_name": "Nicholas B.", "clpid": "Jennings-Nicholas-B" }, { "family_name": "Etemadmoghadam", "given_name": "Dariush", "clpid": "Etemadmoghadam-Dariush" }, { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Jacamo", "given_name": "Rodrigo O.", "clpid": "Jacamo-Rodrigo-O" }, { "family_name": "Barbosa-Morais", "given_name": "Nuno", "clpid": "Barbosa-Morais-Nuno" }, { "family_name": "Le", "given_name": "Xiao-Feng", "clpid": "Le-Xiao-Feng" }, { "family_name": "Vivas-Mejia", "given_name": "Pablo", "clpid": "Vivas-Mejia-Pablo" }, { "family_name": "Lopez-Berestein", "given_name": "Gabriel", "clpid": "Lopez-Berestein-G" }, { "family_name": "Grandjean", "given_name": "Geoffrey", "clpid": "Grandjean-G" }, { "family_name": "Bartholomeusz", "given_name": "Geoffrey", "clpid": "Bartholomeusz-G" }, { "family_name": "Liao", "given_name": "Warren", "clpid": "Liao-Warren" }, { "family_name": "Andreeff", "given_name": "Michael", "clpid": "Andreeff-Michael" }, { "family_name": "Bowtell", "given_name": "David", "clpid": "Bowtell-David" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Sood", "given_name": "Anil K.", "clpid": "Sood-Anil-K" }, { "family_name": "Bast", "given_name": "Robert C.", "clpid": "Bast-Robert-C" }, { "literal": "Australian Ovarian Cancer Study Group" } ], "abstract": "Regulators of mitosis have been successfully targeted to enhance response to taxane chemotherapy. Here, we show that the salt inducible kinase 2 (SIK2) localizes at the centrosome, plays a key role in the initiation of mitosis, and regulates the localization of the centrosome linker protein, C-Nap1, through S2392 phosphorylation. Interference with the known SIK2 inhibitor PKA induced SIK2-dependent centrosome splitting in interphase while SIK2 depletion blocked centrosome separation in mitosis, sensitizing ovarian cancers to paclitaxel in culture and in xenografts. Depletion of SIK2 also delayed G1/S transition and reduced AKT phosphorylation. Higher expression of SIK2 significantly correlated with poor survival in patients with high-grade serous ovarian cancers. We believe these data identify SIK2 as a plausible target for therapy in ovarian cancers.", "doi": "10.1016/j.ccr.2010.06.018", "pmcid": "PMC3954541", "issn": "1535-6108", "publisher": "Cell Press", "publication": "Cancer Cell", "publication_date": "2010-08-17", "series_number": "2", "volume": "18", "issue": "2", "pages": "109-121" }, { "id": "authors:w462y-vvv49", "collection": "authors", "collection_id": "w462y-vvv49", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170352522", "type": "article", "title": "Aurora A contributes to p150\u1d4d\u2071\u1d58\u1d49\u1d48 phosphorylation and function during mitosis", "author": [ { "family_name": "Rom\u00e9", "given_name": "Pierre", "orcid": "0000-0001-5611-5323", "clpid": "Rom\u00e9-P" }, { "family_name": "Montembault", "given_name": "Emilie", "orcid": "0000-0002-4850-3622", "clpid": "Montembault-E" }, { "family_name": "Franck", "given_name": "Nathalie", "clpid": "Franck-Nathalie" }, { "family_name": "Pascal", "given_name": "Aude", "clpid": "Pascal-Aude" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Giet", "given_name": "R\u00e9gis", "orcid": "0000-0001-9027-5849", "clpid": "Giet-R" } ], "abstract": "Aurora A is a spindle pole\u2013associated protein kinase required for mitotic spindle assembly and chromosome segregation. In this study, we show that Drosophila melanogaster aurora A phosphorylates the dynactin subunit p150\u1d4d\u2071\u1d58\u1d49\u1d48 on sites required for its association with the mitotic spindle. Dynactin strongly accumulates on microtubules during prophase but disappears as soon as the nuclear envelope breaks down, suggesting that its spindle localization is tightly regulated. If aurora A's function is compromised, dynactin and dynein become enriched on mitotic spindle microtubules. Phosphorylation sites are localized within the conserved microtubule-binding domain (MBD) of the p150\u1d4d\u2071\u1d58\u1d49\u1d48. Although wild-type p150\u1d4d\u2071\u1d58\u1d49\u1d48 binds weakly to spindle microtubules, a variant that can no longer be phosphorylated by aurora A remains associated with spindle microtubules and fails to rescue depletion of endogenous p150\u1d4d\u2071\u1d58\u1d49\u1d48. Our results suggest that aurora A kinase participates in vivo to the phosphoregulation of the p150\u1d4d\u2071\u1d58\u1d49\u1d48 MBD to limit the microtubule binding of the dynein\u2013dynactin complex and thus regulates spindle assembly.", "doi": "10.1083/jcb.201001144", "pmcid": "PMC2872913", "issn": "1540-8140", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2010-05-17", "series_number": "4", "volume": "189", "issue": "4", "pages": "651-659" }, { "id": "authors:dz1h0-dr993", "collection": "authors", "collection_id": "dz1h0-dr993", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190417-163114958", "type": "article", "title": "Origin and formation of the first two distinct cell types of the inner cell mass in the mouse embryo", "author": [ { "family_name": "Morris", "given_name": "Samantha A.", "clpid": "Morris-S-A" }, { "family_name": "Teo", "given_name": "Roy T. Y.", "clpid": "Teo-Roy-T-Y" }, { "family_name": "Li", "given_name": "Huiliang", "clpid": "Li-Huiliang" }, { "family_name": "Robson", "given_name": "Paul", "clpid": "Robson-P" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "A crucial question in mammalian development is how cells of the early embryo differentiate into distinct cell types. The first decision is taken when cells undertake waves of asymmetric division that generate one daughter on the inside and one on the outside of the embryo. After this division, some cells on the inside remain pluripotent and give rise to the epiblast, and hence the future body, whereas others develop into the primitive endoderm, an extraembryonic tissue. How the fate of these inside cells is decided is unknown: Is the process random, or is it related to their developmental origins? To address this question, we traced all cells by live-cell imaging in intact, unmanipulated embryos until the epiblast and primitive endoderm became distinct. This analysis revealed that inner cell mass (ICM) cells have unrestricted developmental potential. However, cells internalized by the first wave of asymmetric divisions are biased toward forming pluripotent epiblast, whereas cells internalized in the next two waves of divisions are strongly biased toward forming primitive endoderm. Moreover, we show that cells internalized by the second wave up-regulate expression of Gata6 and Sox17, and changing the expression of these genes determines whether the cells become primitive endoderm. Finally, with our ability to determine the origin of cells, we find that inside cells that are mispositioned when they are born can sort into the correct layer. In conclusion, we propose a model in which the timing of cell internalization, cell position, and cell sorting combine to determine distinct lineages of the preimplantation mouse embryo.", "doi": "10.1073/pnas.0915063107", "pmcid": "PMC2852013", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "2010-04-06", "series_number": "14", "volume": "107", "issue": "14", "pages": "6364-6369" }, { "id": "authors:tdsfh-cm289", "collection": "authors", "collection_id": "tdsfh-cm289", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144713931", "type": "article", "title": "Drosophila Klp67A binds prophase kinetochores to subsequently regulate congression and spindle length", "author": [ { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The kinesin-8 proteins are a family of microtubule-depolymerising motor molecules, which, despite their highly conserved roles in chromosome alignment and spindle dynamics, remain poorly characterised. Here, we report that the Drosophila kinesin-8 protein, Klp67A, exists in two spatially and functionally separable metaphase pools: at kinetochores and along the spindle. Fixed and live-cell analyses of different Klp67A recombinant variants indicate that this kinesin-8 first collects at kinetochores during prophase and, by metaphase, localises to the kinetochore outerplate. Although the catalytic motor activity of Klp67A is required for efficient kinetochore recruitment at all times, microtubules are entirely dispensable for this process. The tail of Klp67A does not play a role in kinetochore accumulation, but is both necessary and sufficient for spindle association. Using functional assays, we reveal that chromosome position and spindle length are determined by the microtubule-depolymerising motor activity of Klp67A exclusively when located at kinetochores, but not along the spindle. These data reveal that, unlike other metazoan kinesin-8 proteins, Klp67A binds the nascent prophase and mature metaphase kinetochore. From this location, Klp67A uses its motor activity to ensure chromosome alignment and proper spindle length.", "doi": "10.1242/jcs.055905", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2010-03-01", "series_number": "5", "volume": "123", "issue": "5", "pages": "767-776" }, { "id": "authors:m1a28-h5z19", "collection": "authors", "collection_id": "m1a28-h5z19", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190417-163115057", "type": "article", "title": "CARM1 Is Required in Embryonic Stem Cells to Maintain Pluripotency and Resist Differentiation", "author": [ { "family_name": "Wu", "given_name": "Qiang", "clpid": "Wu-Qiang" }, { "family_name": "Bruce", "given_name": "Alexander W.", "clpid": "Bruce-A-W" }, { "family_name": "Jedrusik", "given_name": "Agnieszka", "clpid": "Jedrusik-A" }, { "family_name": "Ellis", "given_name": "Peter D.", "clpid": "Ellis-P-D" }, { "family_name": "Andrews", "given_name": "Robert M.", "clpid": "Andrews-R-M" }, { "family_name": "Langford", "given_name": "Cordelia F.", "clpid": "Langford-C-F" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Histone H3 methylation at R17 and R26 recently emerged as a novel epigenetic mechanism regulating pluripotency in mouse embryos. Blastomeres of four\u2010cell embryos with high H3 methylation at these sites show unrestricted potential, whereas those with lower levels cannot support development when aggregated in chimeras of like cells. Increasing histone H3 methylation, through expression of coactivator\u2010associated\u2010protein\u2010arginine\u2010methyltransferase 1 (CARM1) in embryos, elevates expression of key pluripotency genes and directs cells to the pluripotent inner cell mass. We demonstrate CARM1 is also required for the self\u2010renewal and pluripotency of embryonic stem (ES) cells. In ES cells, CARM1 depletion downregulates pluripotency genes leading to their differentiation. CARM1 associates with Oct4/Pou5f1 and Sox2 promoters that display detectable levels of R17/26 histone H3 methylation. In CARM1 overexpressing ES cells, histone H3 arginine methylation is also at the Nanog promoter to which CARM1 now associates. Such cells express Nanog at elevated levels and delay their response to differentiation signals. Thus, like in four\u2010cell embryo blastomeres, histone H3 arginine methylation by CARM1 in ES cells allows epigenetic modulation of pluripotency.", "doi": "10.1002/stem.131", "pmcid": "PMC4135545", "issn": "1066-5099", "publisher": "Wiley", "publication": "Stem Cells", "publication_date": "2009-11", "series_number": "11", "volume": "27", "issue": "11", "pages": "2637-2645" }, { "id": "authors:2378z-czq39", "collection": "authors", "collection_id": "2378z-czq39", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163115803", "type": "article", "title": "Drosophila Larp associates with poly(A)-binding protein and is required for male fertility and syncytial embryo development", "author": [ { "family_name": "Blagden", "given_name": "Sarah P.", "clpid": "Blagden-S-P" }, { "family_name": "Gatt", "given_name": "Melanie K.", "clpid": "Gatt-M-K" }, { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Lada", "given_name": "Karolina", "clpid": "Lada-K" }, { "family_name": "Ichihara", "given_name": "Keiko", "clpid": "Ichihara-Keiko" }, { "family_name": "Lilley", "given_name": "Kathryn S.", "orcid": "0000-0003-0594-6543", "clpid": "Lilly-K-S" }, { "family_name": "Inoue", "given_name": "Yoshihiro H.", "clpid": "Inoue-Yoshihiro-H" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "As the influence of mRNA translation upon cell cycle regulation becomes clearer, we searched for genes that might specify such control in Drosophila. A maternal-effect lethal screen identified mutants in the Drosophila gene for Larp (La-related protein) which displayed maternal-effect lethality and male sterility. A role for La protein has already been implicated in mRNA translation whereas Larp has been proposed to regulate mRNA stability. Here we demonstrate that Larp exists in a physical complex with, and also interacts genetically with, the translation regulator poly(A)-binding protein (PABP). Most mutant alleles of pAbp are embryonic lethal. However hypomorphic pAbp alleles show similar meiotic defects to larp mutants. We find that larp mutant-derived syncytial embryos show a range of mitotic phenotypes, including failure of centrosomes to migrate around the nuclear envelope, detachment of centrosomes from spindle poles, the formation of multipolar spindle arrays and cytokinetic defects. We discuss why the syncytial mitotic cycles and male meiosis should have a particularly sensitive requirement for Larp proteins in regulating not only transcript stability but also potentially the translation of mRNAs.", "doi": "10.1016/j.ydbio.2009.07.016", "issn": "0012-1606", "publisher": "Elsevier", "publication": "Developmental Biology", "publication_date": "2009-10-01", "series_number": "1", "volume": "334", "issue": "1", "pages": "186-197" }, { "id": "authors:jdmpn-cd369", "collection": "authors", "collection_id": "jdmpn-cd369", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150625835", "type": "article", "title": "The SCF/Slimb Ubiquitin Ligase Limits Centrosome Amplification through Degradation of SAK/PLK4", "author": [ { "family_name": "Cunha-Ferreira", "given_name": "In\u00eas", "clpid": "Cunha-Ferreira-In\u00eas" }, { "family_name": "Rodrigues-Martins", "given_name": "Ana", "clpid": "Rodrigues-Martins-Ana" }, { "family_name": "Bento", "given_name": "In\u00eas", "clpid": "Bento-In\u00eas" }, { "family_name": "Riparbelli", "given_name": "Maria", "clpid": "Riparbelli-M-G" }, { "family_name": "Zhang", "given_name": "Wei", "clpid": "Zhang-Wei" }, { "family_name": "Laue", "given_name": "Ernest", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Bettencourt-Dias", "given_name": "M\u00f3nica", "clpid": "Bettencourt-Dias-M" } ], "abstract": "Centrioles are essential for the formation of microtubule-derived structures, including cilia and centrosomes. Abnormalities in centrosome number and structure occur in many cancers and are associated with genomic instability [1]. In most dividing animal cells, centriole formation is coordinated with DNA replication and is highly regulated such that only one daughter centriole forms close to each mother centriole 1, 2. Centriole formation is triggered and dependent on a conserved kinase, SAK/PLK4 3, 4, 5, 6, 7, 8. Downregulation and overexpression of SAK/PLK4 is associated with cancer in humans, mice, and flies 9, 10, 11. Here we show that centrosome amplification is normally inhibited by degradation of SAK/PK4 degradation, mediated by the SCF/Slimb ubiquitin ligase. This complex physically interacts with SAK/PLK4, and in its absence, SAK/PLK4 accumulates, leading to the striking formation of multiple daughter centrioles surrounding each mother. This interaction is mediated via a conserved Slimb binding motif in SAK/PLK4, mutations of which leads to centrosome amplification. This regulation is likely to be conserved, because knockout of the ortholog of Slimb, \u03b2-Trcp1 in mice, also leads to centrosome amplification [12]. Because the SCF/\u03b2-Trcp complex plays an important role in cell-cycle progression, our results lead to new understanding of the control of centrosome number and how it may go awry in human disease.", "doi": "10.1016/j.cub.2008.11.037", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2009-01-13", "series_number": "1", "volume": "19", "issue": "1", "pages": "43-49" }, { "id": "authors:5x9x2-p2260", "collection": "authors", "collection_id": "5x9x2-p2260", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163115954", "type": "article", "title": "SnapShot: Centriole Biogenesis", "author": [ { "family_name": "Bettencourt-Dias", "given_name": "M\u00f3nica", "clpid": "Bettencourt-Dias-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "[no abstract]", "doi": "10.1016/j.cell.2008.12.035", "issn": "0092-8674", "publisher": "Cell Press", "publication": "Cell", "publication_date": "2009-01-09", "series_number": "1", "volume": "136", "issue": "1", "pages": "188.e1-188.e2" }, { "id": "authors:n59je-yg982", "collection": "authors", "collection_id": "n59je-yg982", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353006", "type": "article", "title": "Sequestration of Polo kinase to microtubules by phosphopriming-independent binding to Map205 is relieved by phosphorylation at a CDK site in mitosis", "author": [ { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Deery", "given_name": "Michael S.", "clpid": "Deery-M-S" }, { "family_name": "Lilley", "given_name": "Kathryn S.", "orcid": "0000-0003-0594-6543", "clpid": "Lilly-K-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The conserved Polo kinase controls multiple events in mitosis and cytokinesis. Although Polo-like kinases are regulated by phosphorylation and proteolysis, control of subcellular localization plays a major role in coordinating their mitotic functions. This is achieved largely by the Polo-Box Domain, which binds prephosphorylated targets. However, it remains unclear whether and how Polo might interact with partner proteins when priming mitotic kinases are inactive. Here we show that Polo associates with microtubules in interphase and cytokinesis, through a strong interaction with the microtubule-associated protein Map205. Surprisingly, this interaction does not require priming phosphorylation of Map205, and the Polo-Box Domain of Polo is required but not sufficient for this interaction. Moreover, phosphorylation of Map205 at a CDK site relieves this interaction. Map205 can stabilize Polo and inhibit its cellular activity in vivo. In syncytial embryos, the centrosome defects observed in polo hypomorphs are enhanced by overexpression of Map205 and suppressed by its deletion. We propose that Map205-dependent targeting of Polo to microtubules provides a stable reservoir of Polo that can be rapidly mobilized by the activity of Cdk1 at mitotic entry.", "doi": "10.1101/gad.486808", "pmcid": "PMC2559908", "issn": "0890-9369", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Genes and Development", "publication_date": "2008-10-01", "series_number": "19", "volume": "22", "issue": "19", "pages": "2707-2720" }, { "id": "authors:rymvf-r2p38", "collection": "authors", "collection_id": "rymvf-r2p38", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150625965", "type": "article", "title": "A Bitter PP1 Fights the Sweet Polo", "author": [ { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Chen", "given_name": "Feng", "clpid": "Chen-Feng" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "In a recent paper in Developmental Cell, Yamashiro et al. (2008) report that the PP1 regulatory subunit MYPT1 interacts with PLK1 and antagonizes essential mitotic functions of PLK1, at least in part by promoting the dephosphorylation of PLK1 at Thr210.", "doi": "10.1016/j.molcel.2008.05.012", "issn": "1097-2765", "publisher": "Cell Press", "publication": "Molecular Cell", "publication_date": "2008-06-05", "series_number": "5", "volume": "30", "issue": "5", "pages": "541-542" }, { "id": "authors:2xw4g-wfr62", "collection": "authors", "collection_id": "2xw4g-wfr62", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140639400", "type": "article", "title": "Interaction between Anillin and RacGAP50C connects the actomyosin contractile ring with spindle microtubules at the cell division site", "author": [ { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Takeda", "given_name": "Tetsuya", "orcid": "0000-0002-3183-6551", "clpid": "Takeda-Tetsuya" }, { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Zhang", "given_name": "Wei", "clpid": "Zhang-Wei" }, { "family_name": "Lilley", "given_name": "Kathryn S.", "orcid": "0000-0003-0594-6543", "clpid": "Lilly-K-S" }, { "family_name": "Laue", "given_name": "Ernest D.", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Anillin, one of the first factors recruited to the cleavage site during cytokinesis, interacts with actin, myosin II and septins, and is essential for proper organization of the actomyosin contractile ring. We employed affinity-purification methodology coupled with mass spectrometry to identify Anillin-interacting molecules in Drosophila cells. We isolated several actin and myosin proteins, three of the five Drosophila septins and RacGAP50C (Tum), a component of the centralspindlin complex. Using drug and RNA interference (RNAi) treatments we established that F-actin is essential for Anillin cortical localization in prometaphase but not for its accumulation at the cleavage furrow after anaphase onset. Moreover, septins were not recruited to the cleavage site in cells in which Anillin was knocked down by RNAi, but localized to central-spindle microtubules, suggesting that septins travel along microtubules to interact with Anillin at the furrow. Finally, we demonstrate that RacGAP50C is necessary for Anillin accumulation at the furrow and that the two proteins colocalize in vivo and interact in vitro. Thus, in addition to its role in activating RhoA signalling, RacGAP50C also controls the proper assembly of the actomyosin ring by interacting with Anillin at the cleavage furrow.", "doi": "10.1242/jcs.026716", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2008-04-15", "series_number": "8", "volume": "121", "issue": "8", "pages": "1151-1158" }, { "id": "authors:m2x13-agj93", "collection": "authors", "collection_id": "m2x13-agj93", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-122118365", "type": "article", "title": "Yeast Polo-like kinase substrates are nailed with the right tools", "author": [ { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "A platform has been built combining chemical genetics and bioinformatics to screen the proteome for physiological substrates of the Polo-like kinase in budding yeast. A novel role for this kinase in regulating the mitotic spindle is revealed.", "doi": "10.1186/gb-2008-9-1-203", "pmcid": "PMC2395232", "issn": "1465-6906", "publisher": "BioMed Central", "publication": "Genome Biology", "publication_date": "2008-01-30", "volume": "9", "pages": "Art.No. 203" }, { "id": "authors:dcgkm-hfz57", "collection": "authors", "collection_id": "dcgkm-hfz57", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351991", "type": "article", "title": "Mutations in Drosophila Greatwall/Scant Reveal Its Roles in Mitosis and Meiosis and Interdependence with Polo Kinase", "author": [ { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Zhao", "given_name": "Xinbei", "clpid": "Zhao-Xinbei" }, { "family_name": "White-Cooper", "given_name": "Helen", "orcid": "0000-0002-3373-8023", "clpid": "White-Cooper-H" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Polo is a conserved kinase that coordinates many events of mitosis and meiosis, but how it is regulated remains unclear. Drosophila females having only one wild-type allele of the polo kinase gene and the dominant Scant mutation produce embryos in which one of the centrosomes detaches from the nuclear envelope in late prophase. We show that Scant creates a hyperactive form of Greatwall (Gwl) with altered specificity in vitro, another protein kinase recently implicated in mitotic entry in Drosophila and Xenopus. Excess Gwl activity in embryos causes developmental failure that can be rescued by increasing maternal Polo dosage, indicating that coordination between the two mitotic kinases is crucial for mitotic progression. Revertant alleles of Scant that restore fertility to polo\u2013Scant heterozygous females are recessive alleles or deficiencies of gwl; they show chromatin condensation defects and anaphase bridges in larval neuroblasts. One recessive mutant allele specifically disrupts a Gwl isoform strongly expressed during vitellogenesis. Females hemizygous for this allele are sterile, and their oocytes fail to arrest in metaphase I of meiosis; both homologues and sister chromatids separate on elongated meiotic spindles with little or no segregation. This allelic series of gwl mutants highlights the multiple roles of Gwl in both mitotic and meiotic progression. Our results indicate that Gwl activity antagonizes Polo and thus identify an important regulatory interaction of the cell cycle.", "doi": "10.1371/journal.pgen.0030200", "pmcid": "PMC2065886", "issn": "1553-7404", "publisher": "Public Library of Science", "publication": "PLOS Genetics", "publication_date": "2007-11-09", "series_number": "11", "volume": "3", "issue": "11", "pages": "Art. No. e200" }, { "id": "authors:tfk9s-p7y36", "collection": "authors", "collection_id": "tfk9s-p7y36", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626070", "type": "article", "title": "DSAS-6 Organizes a Tube-like Centriole Precursor, and Its Absence Suggests Modularity in Centriole Assembly", "author": [ { "family_name": "Rodrigues-Martins", "given_name": "Ana", "clpid": "Rodrigues-Martins-Ana" }, { "family_name": "Bettencourt-Dias", "given_name": "M\u00f3nica", "clpid": "Bettencourt-Dias-M" }, { "family_name": "Riparbelli", "given_name": "Maria", "clpid": "Riparbelli-M-G" }, { "family_name": "Ferreira", "given_name": "Cl\u00e1udia", "clpid": "Ferreira-Cl\u00e1udia" }, { "family_name": "Ferreira", "given_name": "In\u00eas", "clpid": "Ferreira-In\u00eas" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Centrioles are microtubule-based cylindrical structures that exhibit 9-fold symmetry and facilitate the organization of centrosomes, flagella, and cilia [1]. Abnormalities in centrosome structure and number occur in many cancers 1, 2. Despite its importance, very little is known about centriole biogenesis. Recent studies in C. elegans have highlighted a group of molecules necessary for centriole assembly 1, 3. ZYG-1 kinase recruits a complex of two coiled-coil proteins, SAS-6 and SAS-5, which are necessary to form the C. elegans centriolar tube, a scaffold in centriole formation 4, 5. This complex also recruits SAS-4, which is required for the assembly of the centriolar microtubules that decorate that tube 4, 5. Here we show that Drosophila SAS-6 is involved in centriole assembly and cohesion. Overexpression of DSAS-6 in syncitial embryos led to the de novo formation of multiple microtubule-organizing centers (MTOCs). Strikingly, the center of these MTOCs did not contain centrioles, as described previously for SAK/PLK4 overexpression [6]. Instead, tube-like structures were present, supporting the idea that centriolar assembly starts with the formation of a tube-like scaffold, dependent on DSAS-6 [5]. In DSAS-6 loss-of-function mutants, centrioles failed to close and to elongate the structure along all axes of the 9-fold symmetry, suggesting modularity in centriole assembly. We propose that the tube is built from nine subunits fitting together laterally and longitudinally in a modular and sequential fashion, like pieces of a layered \"hollow\" cake.", "doi": "10.1016/j.cub.2007.07.034", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2007-09-04", "series_number": "17", "volume": "17", "issue": "17", "pages": "1465-1472" }, { "id": "authors:8z658-3jt35", "collection": "authors", "collection_id": "8z658-3jt35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351684", "type": "article", "title": "Recruitment of Polo Kinase to the Spindle Midzone during Cytokinesis Requires the Feo/Klp3A Complex", "author": [ { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Zhang", "given_name": "Wei", "clpid": "Zhang-Wei" }, { "family_name": "Lilley", "given_name": "Kathryn S.", "orcid": "0000-0003-0594-6543", "clpid": "Lilly-K-S" }, { "family_name": "Laue", "given_name": "Ernest", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Background: Polo-like kinases control multiple events during cell division, including mitotic entry, centrosome organization, spindle formation, chromosome segregation and cytokinesis. Their roles during cytokinesis, however, are not well understood because the requirement of these kinases during early stages of mitosis complicates the study of their functions after anaphase onset. \n\nMethodology/Principal Findings: We used time-lapse microscopy to analyze the dynamics of Polo::GFP in Drosophila tissue culture cells during mitosis. After anaphase onset, Polo::GFP concentrated at the spindle midzone, but also diffused along the entire length of the central spindle. Using RNA interference we demonstrate that the microtubule-associated proteins Feo and Klp3A are required for Polo recruitment to the spindle midzone, but not the kinesin Pavarotti as previously thought. Moreover, we show that Feo and Klp3A form a complex and that Polo co-localizes with both proteins during cytokinesis. \n\nConclusion/Significance: Our results reveal that the Feo/Klp3A complex is necessary for Polo recruitment to the spindle midzone. A similar finding has also been recently reported in mammalian cells [1], suggesting that this basic mechanism has been conserved during evolution, albeit with some differences. Finally, since cleavage furrow formation and ingression are unaffected following feo RNAi, our data imply that Polo recruitment to the central spindle is not required for furrowing, but some other aspect of cytokinesis.", "doi": "10.1371/journal.pone.0000572", "pmcid": "PMC1894651", "issn": "1932-6203", "publisher": "Public Library of Science", "publication": "PLoS ONE", "publication_date": "2007-06-26", "series_number": "6", "volume": "2", "issue": "6", "pages": "Art. No. e572" }, { "id": "authors:fwywn-5dx75", "collection": "authors", "collection_id": "fwywn-5dx75", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351789", "type": "article", "title": "Molecular Analysis of Core Kinetochore Composition and Assembly in Drosophila melanogaster", "author": [ { "family_name": "Przewloka", "given_name": "Marcin R.", "orcid": "0000-0002-0329-9162", "clpid": "Przewloka-M-R" }, { "family_name": "Zhang", "given_name": "Wei", "clpid": "Zhang-Wei" }, { "family_name": "Costa", "given_name": "Patricia", "clpid": "Costa-Patricia" }, { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Lilley", "given_name": "Kathryn S.", "orcid": "0000-0003-0594-6543", "clpid": "Lilly-K-S" }, { "family_name": "Laue", "given_name": "Ernest D.", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" }, { "family_name": "McAinsh", "given_name": "Andrew D.", "orcid": "0000-0001-6808-0711", "clpid": "McAinsh-A-D" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Background. Kinetochores are large multiprotein complexes indispensable for proper chromosome segregation. Although Drosophila is a classical model organism for studies of chromosome segregation, little is known about the organization of its kinetochores. \n\nMethodology/Principal Findings. We employed bioinformatics, proteomics and cell biology methods to identify and analyze the interaction network of Drosophila kinetochore proteins. We have shown that three Drosophila proteins highly diverged from human and yeast Ndc80, Nuf2 and Mis12 are indeed their orthologues. Affinity purification of these proteins from cultured Drosophila cells identified a further five interacting proteins with weak similarity to subunits of the SPC105/KNL-1, MIND/MIS12 and NDC80 kinetochore complexes together with known kinetochore associated proteins such as dynein/dynactin, spindle assembly checkpoint components and heterochromatin proteins. All eight kinetochore complex proteins were present at the kinetochore during mitosis and MIND/MIS12 complex proteins were also centromeric during interphase. Their down-regulation led to dramatic defects in chromosome congression/segregation frequently accompanied by mitotic spindle elongation. The systematic depletion of each individual protein allowed us to establish dependency relationships for their recruitment onto the kinetochore. This revealed the sequential recruitment of individual members of first, the MIND/MIS12 and then, NDC80 complex. \n\nConclusions/Significance. The Drosophila MIND/MIS12 and NDC80 complexes and the Spc105 protein, like their counterparts from other eukaryotic species, are essential for chromosome congression and segregation, but are highly diverged in sequence. Hierarchical dependence relationships of individual proteins regulate the assembly of Drosophila kinetochore complexes in a manner similar, but not identical, to other organisms.", "doi": "10.1371/journal.pone.0000478", "pmcid": "PMC1868777", "issn": "1932-6203", "publisher": "Public Library of Science", "publication": "PLoS ONE", "publication_date": "2007-05-30", "series_number": "5", "volume": "2", "issue": "5", "pages": "Art. No. e478" }, { "id": "authors:vj7ar-qbq73", "collection": "authors", "collection_id": "vj7ar-qbq73", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140639487", "type": "article", "title": "Revisiting the Role of the Mother Centriole in Centriole Biogenesis", "author": [ { "family_name": "Rodrigues-Martins", "given_name": "A.", "clpid": "Rodrigues-Martins-Ana" }, { "family_name": "Riparbelli", "given_name": "M.", "clpid": "Riparbelli-M-G" }, { "family_name": "Callaini", "given_name": "G.", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Bettencourt-Dias", "given_name": "M.", "clpid": "Bettencourt-Dias-M" } ], "abstract": "Centrioles duplicate once in each cell division cycle through so-called templated or canonical duplication. SAK, also called PLK4 (SAK/PLK4), a kinase implicated in tumor development, is an upstream regulator of canonical biogenesis necessary for centriole formation. We found that overexpression of SAK/PLK4 could induce amplification of centrioles in Drosophila embryos and their de novo formation in unfertilized eggs. Both processes required the activity of DSAS-6 and DSAS-4, two molecules required for canonical duplication. Thus, centriole biogenesis is a template-free self-assembly process triggered and regulated by molecules that ordinarily associate with the existing centriole. The mother centriole is not a bona fide template but a platform for a set of regulatory molecules that catalyzes and regulates daughter centriole assembly.", "doi": "10.1126/science.1142950", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "2007-05-18", "series_number": "5827", "volume": "316", "issue": "5827", "pages": "1046-1050" }, { "id": "authors:kbbyn-4xf20", "collection": "authors", "collection_id": "kbbyn-4xf20", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626199", "type": "article", "title": "Multiple Protein Phosphatases Are Required for Mitosis in Drosophila", "author": [ { "family_name": "Chen", "given_name": "Feng", "clpid": "Chen-Feng" }, { "family_name": "Archambault", "given_name": "Vincent", "orcid": "0000-0002-2857-7667", "clpid": "Archambault-V" }, { "family_name": "Kar", "given_name": "Ashok", "clpid": "Kar-Ashok" }, { "family_name": "Lio'", "given_name": "Pietro", "clpid": "Lio'-Pietro" }, { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Sinka", "given_name": "Rita", "clpid": "Sinka-Rita" }, { "family_name": "Lilley", "given_name": "Kathryn", "orcid": "0000-0003-0594-6543", "clpid": "Lilly-K-S" }, { "family_name": "Laue", "given_name": "Ernest D.", "orcid": "0000-0002-7476-4148", "clpid": "Laue-Ernest-D" }, { "family_name": "Deak", "given_name": "Peter", "clpid": "Deak-Peter" }, { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Background. Approximately one-third of the Drosophila kinome has been ascribed some cell-cycle function. However, little is known about which of its 117 protein phosphatases (PPs) or subunits have counteracting roles. \n\nResults. We investigated mitotic roles of PPs through systematic RNAi. We found that G\u2082-M progression requires Puckered, the JNK MAP-kinase inhibitory phosphatase and PP2C in addition to string (Cdc25). Strong mitotic arrest and chromosome congression failure occurred after Pp1-87B downregulation. Chromosome alignment and segregation defects also occurred after knockdown of PP1-Flapwing, not previously thought to have a mitotic role. Reduction of several nonreceptor tyrosine phosphatases produced spindle and chromosome behavior defects, and for corkscrew, premature chromatid separation. RNAi of the dual-specificity phosphatase, Myotubularin, or the related Sbf \"antiphosphatase\" resulted in aberrant mitotic chromosome behavior. Finally, for PP2A, knockdown of the catalytic or A subunits led to bipolar monoastral spindles, knockdown of the Twins B subunit led to bridged and lagging chromosomes, and knockdown of the B\u2032 Widerborst subunit led to scattering of all mitotic chromosomes. Widerborst was associated with MEI-S332 (Shugoshin) and required for its kinetochore localization. \n\nConclusions. We identify cell-cycle roles for 22 of 117 Drosophila PPs. Involvement of several PPs in G\u2082 suggests multiple points for its regulation. Major mitotic roles are played by PP1 with tyrosine PPs and Myotubularin-related PPs having significant roles in regulating chromosome behavior. Finally, depending upon its regulatory subunits, PP2A regulates spindle bipolarity, kinetochore function, and progression into anaphase. Discovery of several novel cell-cycle PPs identifies a need for further studies of protein dephosphorylation.", "doi": "10.1016/j.cub.2007.01.068", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2007-02-20", "series_number": "4", "volume": "17", "issue": "4", "pages": "293-303" }, { "id": "authors:s7w9v-y5a10", "collection": "authors", "collection_id": "s7w9v-y5a10", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123358676", "type": "article", "title": "RacGAP50C is sufficient to signal cleavage furrow formation during cytokinesis", "author": [ { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Capalbo", "given_name": "Luisa", "clpid": "Capalbo-L" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Several studies indicate that spindle microtubules determine the position of the cleavage plane at the end of cell division, but their exact role in triggering the formation and ingression of the cleavage furrow is still unclear. Here we show that in Drosophila depletion of either the GAP (GTPase-activating protein) or the kinesin-like subunit of the evolutionary conserved centralspindlin complex prevents furrowing without affecting the association of astral microtubules with the cell cortex. Moreover, time-lapse imaging indicates that astral microtubules serve to deliver the centralspindlin complex to the equatorial cortex just before furrow formation. However, when the GAP-signaling component was mislocalized around the entire cortex using a membrane-tethering motif, this caused ectopic furrowing even in the absence of its motor partner. Thus, the GAP component of centralspindlin is both necessary and sufficient for furrow formation and ingression and astral microtubules provide a route for its delivery to the cleavage site.", "doi": "10.1242/jcs.03210", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2006-11-01", "series_number": "21", "volume": "119", "issue": "21", "pages": "4402-4408" }, { "id": "authors:epj07-e9k44", "collection": "authors", "collection_id": "epj07-e9k44", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140639688", "type": "article", "title": "The Drosophila phosphatidylinositol transfer protein encoded by vibrator is essential to maintain cleavage-furrow ingression in cytokinesis", "author": [ { "family_name": "Gatt", "given_name": "Melanie K.", "clpid": "Gatt-M-K" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Cytokinesis requires the coordination of cytoskeletal and plasma membrane dynamics. A role for phosphatidylinositol lipids has been proposed for the successful completion of cytokinesis but this is still poorly characterised. Here, we show mutants of the gene vibrator, previously found to encode the Drosophila phosphatidylinositol transfer protein, produce multinucleate cells indicative of cytokinesis failure in male meiosis. Examination of fixed preparations of mutant spermatocytes showed contractile rings of anillin and actin that were of normal appearance at early stages but were larger and less well organised at later stages of cytokinesis than in wild-type cells. Time-lapse imaging revealed sequential defects in cytokinesis of vibrator spermatocytes. In cells that fail cytokinesis, central spindle formation occurred correctly, but furrow ingression was delayed and the central spindle did not become compressed to the extent seen in wild-type cells. Cells then stalled at this point before the apparent connection between the constricted cytoskeleton and the plasma membrane was lost; the furrow then underwent elastic regression. We discuss these defects in relation to multiple functions of phosphoinositol lipids in regulating actin dynamics and membrane synthesis.", "doi": "10.1242/jcs.02933", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2006-06-10", "series_number": "11", "volume": "119", "issue": "11", "pages": "2225-2235" }, { "id": "authors:j6vrz-vx164", "collection": "authors", "collection_id": "j6vrz-vx164", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140639625", "type": "article", "title": "Antagonistic activities of Klp10A and Orbit regulate spindle length, bipolarity and function in vivo", "author": [ { "family_name": "Laycock", "given_name": "Joseph E.", "clpid": "Laycock-J-E" }, { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The metaphase-spindle steady-state length occurs as spindle microtubules `flux', incorporating new subunits at their plus ends, while simultaneously losing subunits from their minus ends. Orbit/Mast/CLASP is required for tubulin subunit addition at kinetochores, and several kinesins regulate spindle morphology and/or flux by serving as microtubule depolymerases. Here, we use RNA interference in S2 cells to examine the relationship between Orbit and the four predicted kinesin-type depolymerases encoded by the Drosophila genome (Klp10A, Klp59C, Klp59D and Klp67A). Single depletion of Orbit results in monopolar spindles, mitotic arrest and a subsequent increase in apoptotic cells. These phenotypes are rescued by co-depleting Klp10A but none of the other three depolymerases. Spindle bipolarity is restored by preventing the spindle collapse seen in cells that lack Orbit, leading to functional spindles that are similar to controls in shape and length. We conclude that Klp10A exclusively antagonises Orbit in the regulation of bipolar spindle formation and maintenance.", "doi": "10.1242/jcs.02957", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2006-06", "series_number": "11", "volume": "119", "issue": "11", "pages": "2354-2361" }, { "id": "authors:rzspx-r2h54", "collection": "authors", "collection_id": "rzspx-r2h54", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114539790", "type": "article", "title": "PITSLRE/CDK11\u1d56\u2075\u2078 protein kinase promotes centrosome maturation and bipolar spindle formation", "author": [ { "family_name": "Petretti", "given_name": "Clotilde", "clpid": "Petretti-C" }, { "family_name": "Savoian", "given_name": "Matthew", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Montembault", "given_name": "Emilie", "orcid": "0000-0002-4850-3622", "clpid": "Montembault-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Prigent", "given_name": "Claude", "orcid": "0000-0001-8515-8699", "clpid": "Prigent-C" }, { "family_name": "Giet", "given_name": "R\u00e9gis", "orcid": "0000-0001-9027-5849", "clpid": "Giet-R" } ], "abstract": "The CDK11 (cyclin\u2010dependent kinase 11) gene has an internal ribosome entry site (IRES), allowing the expression of two protein kinases. The longer 110\u2010kDa isoform is expressed at constant levels during the cell cycle and the shorter 58\u2010kDa isoform is expressed only during G2 and M phases. By means of RNA interference (RNAi), we show that the CDK11 gene is required for mitotic spindle formation. CDK11 RNAi leads to mitotic checkpoint activation. Mitotic cells are arrested with short or monopolar spindles. \u03b3\u2010Tubulin as well as Plk1 and Aurora A protein kinase levels are greatly reduced at centrosomes, resulting in microtubule nucleation defects. We show that the mitotic CDK11\u1d56\u2075\u2078 isoform, but not the CDK11\u1d56\u00b9\u00b9\u2070 isoform, associates with mitotic centrosomes and rescues the phenotypes resulting from CDK11 RNAi. This work demonstrates for the first time the role of CDK11\u1d56\u2075\u2078 in centrosome maturation and bipolar spindle morphogenesis.", "doi": "10.1038/sj.embor.7400639", "pmcid": "PMC1456919", "issn": "1469-221X", "publisher": "European Molecular Biology Organization", "publication": "EMBO Reports", "publication_date": "2006-03-01", "series_number": "4", "volume": "7", "issue": "4", "pages": "418-424" }, { "id": "authors:7w824-sph11", "collection": "authors", "collection_id": "7w824-sph11", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190419-105737131", "type": "article", "title": "Functional studies of signaling pathways in peri-implantation development of the mouse embryo by RNAi", "author": [ { "family_name": "Soares", "given_name": "Miguel L.", "clpid": "Soares-M-L" }, { "family_name": "Haraguchi", "given_name": "Seiki", "clpid": "Haraguchi-Seiki" }, { "family_name": "Torres-Padilla", "given_name": "Maria-Elena", "clpid": "Torres-Padilla-M-E" }, { "family_name": "Kalmar", "given_name": "Tibor", "clpid": "Kalmar-T" }, { "family_name": "Carpenter", "given_name": "Lee", "clpid": "Carpenter-L" }, { "family_name": "Bell", "given_name": "Graham", "clpid": "Bell-G" }, { "family_name": "Morrison", "given_name": "Alastair", "clpid": "Morrison-A" }, { "family_name": "Ring", "given_name": "Christopher J. A.", "clpid": "Ring-C-J-A" }, { "family_name": "Clarke", "given_name": "Neil J.", "clpid": "Clarke-N-J" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Background: Studies of gene function in the mouse have relied mainly on gene targeting via homologous recombination. However, this approach is difficult to apply in specific windows of time, and to simultaneously knock-down multiple genes. Here we report an efficient method for dsRNA-mediated gene silencing in late cleavage-stage mouse embryos that permits examination of phenotypes at post-implantation stages. \n\nResults: We show that introduction of Bmp4 dsRNA into intact blastocysts by electroporation recapitulates the genetic Bmp4 null phenotype at gastrulation. It also reveals a novel role for Bmp4 in the regulation the anterior visceral endoderm specific gene expression and its positioning. We also show that RNAi can be used to simultaneously target several genes. When applied to the three murine isoforms of Dishevelled, it leads to earlier defects than previously observed in double knock-outs. These include severe delays in post-implantation development and defects in the anterior midline and neural folds at headfold stages. \n\nConclusion: Our results indicate that the BMP4 signalling pathway contributes to the development of the anterior visceral endoderm, and reveal an early functional redundancy between the products of the murine Dishevelled genes. The proposed approach constitutes a powerful tool to screen the functions of genes that govern the development of the mouse embryo.", "doi": "10.1186/1471-213x-5-28", "pmcid": "PMC1363358", "issn": "1471-213X", "publisher": "BioMed Central", "publication": "BMC Developmental Biology", "publication_date": "2005-12-28", "volume": "5", "pages": "Art. No. 28" }, { "id": "authors:y8k15-1hh78", "collection": "authors", "collection_id": "y8k15-1hh78", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163116104", "type": "article", "title": "SAK/PLK4 Is Required for Centriole Duplication and Flagella Development", "author": [ { "family_name": "Bettencourt-Dias", "given_name": "M.", "clpid": "Bettencourt-Dias-M" }, { "family_name": "Rodrigues-Martins", "given_name": "A.", "clpid": "Rodrigues-Martins-A" }, { "family_name": "Carpenter", "given_name": "L.", "clpid": "Carpenter-L" }, { "family_name": "Riparbelli", "given_name": "M.", "clpid": "Riparbelli-M" }, { "family_name": "Lehmann", "given_name": "L.", "clpid": "Lehmann-L" }, { "family_name": "Gatt", "given_name": "M. K.", "clpid": "Gatt-M-K" }, { "family_name": "Carmo", "given_name": "N.", "clpid": "Carmo-N" }, { "family_name": "Balloux", "given_name": "F.", "clpid": "Balloux-F" }, { "family_name": "Callaini", "given_name": "G.", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Background. SAK/PLK4 is a distinct member of the polo-like kinase family. SAK\u2212/\u2212 mice die during embryogenesis, whereas SAK+/\u2212 mice develop liver and lung tumors and SAK+/\u2212 MEFs show mitotic abnormalities. However, the mechanism underlying these phenotypes is still not known. \n\nResults. Here, we show that downregulation of SAK in Drosophila cells, by mutation or RNAi, leads to loss of centrioles, the core structures of centrosomes. Such cells are able to undergo repeated rounds of cell division, but display broad disorganized mitotic spindle poles. We also show that SAK mutants lose their centrioles during the mitotic divisions preceding male meiosis but still produce cysts of 16 primary spermatocytes as in the wild-type. Mathematical modeling of the stereotyped cell divisions of spermatogenesis can account for such loss by defective centriole duplication. The majority of spermatids in SAK mutants lack centrioles and so are unable to make sperm axonemes. Finally, we show that depletion of SAK in human cells also prevents centriole duplication and gives rise to mitotic abnormalities. \n\nConclusions: SAK/PLK4 is necessary for centriole duplication both in Drosophila and human cells. Drosophila cells tolerate the lack of centrioles and undertake mitosis but cannot form basal bodies and hence flagella. Human cells depleted of SAK show error-prone mitosis, likely to underlie its tumor-suppressor role.", "doi": "10.1016/j.cub.2005.11.042", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2005-12-24", "series_number": "24", "volume": "15", "issue": "24", "pages": "2199-2207" }, { "id": "authors:mfa3p-96x92", "collection": "authors", "collection_id": "mfa3p-96x92", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114539934", "type": "article", "title": "Spotted-dick, a zinc-finger protein of Drosophila required for expression of Orc4 and S phase", "author": [ { "family_name": "Page", "given_name": "Andrew R.", "clpid": "Page-Andrew-R" }, { "family_name": "Kovacs", "given_name": "Andras", "clpid": "Kovacs-Andras" }, { "family_name": "Deak", "given_name": "Peter", "clpid": "Deak-Peter" }, { "family_name": "T\u0151r\u0151k", "given_name": "Tibor", "clpid": "T\u0151r\u0151k-Tibor" }, { "family_name": "Kiss", "given_name": "Istvan", "clpid": "Kiss-Istvan" }, { "family_name": "Dario", "given_name": "Paulo", "clpid": "Dario-Paulo" }, { "family_name": "Bastos", "given_name": "Cristina", "clpid": "Bastos-Cristina" }, { "family_name": "Batista", "given_name": "Pedro", "clpid": "Batista-Pedro" }, { "family_name": "Gomes", "given_name": "Rui", "clpid": "Gomes-Rui" }, { "family_name": "Ohkura", "given_name": "Hiro", "clpid": "Ohkura-Hiro" }, { "family_name": "Russell", "given_name": "Steven", "clpid": "Russell-Steven" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The highly condensed chromosomes and chromosome breaks in mitotic cells of a Drosophila mutant, spotted\u2010dick/pita , are the consequence of defects in DNA replication. Reduction of levels of Spotted\u2010dick protein, by either RNAi or mutation, leads to the accumulation of cells that have DNA content intermediate to 2N and 4N in proliferating tissues and also compromises endoreduplication in larval salivary glands. The Spotted\u2010dick Zinc\u2010finger protein is present in the nuclei of cells committed to proliferation but necessary in cells undertaking S phase. We show that Spotted\u2010dick/Pita functions as a transcription factor and that, in cultured S2 cells, it is an activator of expression of some 30 genes that include the Orc4 gene, required for initiation of DNA replication. Chromatin immunoprecipitation indicates that it associates with the genes that it activates in S2 cells together with other sites that could represent genes activated in other tissues. We discuss the role of Spotted\u2010dick in the coordination of cellular growth and DNA replication.", "doi": "10.1038/sj.emboj.7600890", "pmcid": "PMC1356331", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "2005-12-21", "series_number": "24", "volume": "24", "issue": "24", "pages": "4304-4315" }, { "id": "authors:c7qn7-b3682", "collection": "authors", "collection_id": "c7qn7-b3682", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140639742", "type": "article", "title": "Klp67A destabilises pre-anaphase microtubules but subsequently is required to stabilise the central spindle", "author": [ { "family_name": "Gatt", "given_name": "Melanie K.", "clpid": "Gatt-M-K" }, { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Riparbelli", "given_name": "Maria G.", "clpid": "Riparbelli-M-G" }, { "family_name": "Massarelli", "given_name": "Chiara", "clpid": "Massarelli-C" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Klp67A is a member of the Kip3 subfamily of microtubule destabilising kinesins, the loss of which results in abnormally long and stable pre-anaphase microtubules. Here we examine its role during cytokinesis in Drosophila primary spermatocytes that require the coordinated interaction of an interior and peripheral set of central spindle microtubules. In mutants anaphase B spindles elongated with normal kinetics but bent towards the cortex. Both peripheral and interior spindle microtubules then formed diminished bundles of abnormally positioned central spindle microtubules associated with the pavarotti-KLP and KLP3A motor proteins. The minus ends of these were poorly aligned as revealed by Asp protein localisation. Furrows always initiated at the sites of central spindle bundles but could be unilateral or nonequatorially positioned. Ectopic furrows were stimulated by the interior central spindle and formed only after this structure buckled and contacted the cortex. Furrows often halted and regressed as they could not be sustained by the central spindles that became increasing unstable over time and often completely degraded. Consistent with this, actin and anillin failed to form homogenous bands. Thus, the Klp67A microtubule catastrophe factor is required for cytokinesis by regulating both the formation and stability of the central spindle.", "doi": "10.1242/jcs.02410", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2005-06-15", "series_number": "12", "volume": "118", "issue": "12", "pages": "2671-2682" }, { "id": "authors:f2854-a9704", "collection": "authors", "collection_id": "f2854-a9704", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140639832", "type": "article", "title": "Cleavage furrow formation and ingression during animal cytokinesis: a microtubule legacy", "author": [ { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Cytokinesis ensures the proper partitioning of the nuclear and cytoplasmic contents into independent daughter cells at the end of cell division. Although the metazoan mitotic spindle has been implicated in the placement and advancement of the cleavage furrow, the molecules responsible for these processes have remained elusive. Recent studies have provided insights into the role of different microtubule structures and associated proteins in cleavage furrow positioning and ingression together with the signalling events that regulate the dynamics of the equatorial cell cortex during cytokinesis. We try to unify these findings into a general model of cytokinesis in which both astral and central spindle microtubules have the ability to induce furrowing. We further propose that the evolutionarily conserved centralspindlin complex serves as a master controller of cell cleavage in Drosophila by promoting both furrow formation and ingression. The same mechanism might be conserved in other organisms.", "doi": "10.1242/jcs.02335", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2005-04-15", "series_number": "8", "volume": "118", "issue": "8", "pages": "1549-1558" }, { "id": "authors:bbw29-yh191", "collection": "authors", "collection_id": "bbw29-yh191", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190419-105737803", "type": "article", "title": "The first cleavage of the mouse zygote predicts the blastocyst axis", "author": [ { "family_name": "Plusa", "given_name": "Berenika", "clpid": "Plusa-B" }, { "family_name": "Hadjantonakis", "given_name": "Anna-Katerina", "clpid": "Hadjantonakis-A-K" }, { "family_name": "Gray", "given_name": "Dionne", "clpid": "Gray-D" }, { "family_name": "Piotrowska-Nitsche", "given_name": "Karolina", "clpid": "Piotrowska-Nitsche-K" }, { "family_name": "Jedrusik", "given_name": "Agnieszka", "clpid": "Jedrusik-A" }, { "family_name": "Papaioannou", "given_name": "Virginia E.", "clpid": "Papaioannou-V-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "One of the unanswered questions in mammalian development is how the embryonic\u2013abembryonic axis of the blastocyst is first established. It is possible that the first cleavage division contributes to this process, because in most mouse embryos the progeny of one two-cell blastomere primarily populate the embryonic part of the blastocyst and the progeny of its sister populate the abembryonic part1,2,3,4. However, it is not known whether the embryonic\u2013abembryonic axis is set up by the first cleavage itself, by polarity in the oocyte that then sets the first cleavage plane with respect to the animal pole, or indeed whether it can be divorced entirely from the first cleavage and established in relation to the animal pole. Here we test the importance of the orientation of the first cleavage by imposing an elongated shape on the zygote so that the division no longer passes close to the animal pole, marked by the second polar body. Non-invasive lineage tracing shows that even when the first cleavage occurs along the short axis imposed by this experimental treatment, the progeny of the resulting two-cell blastomeres tend to populate the respective embryonic and abembryonic parts of the blastocyst. Thus, the first cleavage contributes to breaking the symmetry of the embryo, generating blastomeres with different developmental characteristics.", "doi": "10.1038/nature03388", "issn": "0028-0836", "publisher": "Nature Publishing Group", "publication": "Nature", "publication_date": "2005-03-17", "series_number": "7031", "volume": "434", "issue": "7031", "pages": "391-395" }, { "id": "authors:94pq2-8a576", "collection": "authors", "collection_id": "94pq2-8a576", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-150756148", "type": "article", "title": "parva germina, a gene involved in germ cell maintenance during male and female Drosophila gametogenesis", "author": [ { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "clpid": "Riparbelli-M-G" }, { "family_name": "Inoue", "given_name": "Yoshihiro", "clpid": "Inoue-Yoshihiro-H" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" } ], "abstract": "We report the initial characterization of a gene, parva germina (pag), required for germ cell maintenance in both males and females. pag gonads contain a small number of germline stem cells at the onset of gametogenesis. In contrast, adult mutant gonads are either empty or have a very small number of germ cells that never develop in 16\u2010cell cysts. Ovarioles and testes, therefore, are rudimentary, and the very few germ cells they contain are unable to differentiate into eggs or sperm. Germline stem cells are progressively depleted over time. The average number of germ cells, therefore, decreases in pag mutant ovarioles with the age of the mother, whereas the proportion of agametic germaria goes up. These observations suggest that the pag gene product is involved in germ cell maintenance in both male and female gametogenesis.", "doi": "10.1002/dvdy.20190", "issn": "1058-8388", "publisher": "Wiley-Liss, Inc.", "publication": "Developmental Dynamics", "publication_date": "2005-03", "series_number": "3", "volume": "232", "issue": "3", "pages": "835-844" }, { "id": "authors:pw1xe-etz31", "collection": "authors", "collection_id": "pw1xe-etz31", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190419-105738009", "type": "article", "title": "Downregulation of Par3 and aPKC function directs cells towards the ICM in the preimplantation mouse embryo", "author": [ { "family_name": "Plusa", "given_name": "Berenika", "clpid": "Plusa-B" }, { "family_name": "Frankenberg", "given_name": "Stephen", "clpid": "Frankenberg-S" }, { "family_name": "Chalmers", "given_name": "Andrew", "clpid": "Chalmers-A" }, { "family_name": "Hadjantonakis", "given_name": "Anna-Katerina", "clpid": "Hadjantonakis-A-K" }, { "family_name": "Moore", "given_name": "Catherine A.", "clpid": "Moore-C-A" }, { "family_name": "Papalopulu", "given_name": "Nancy", "clpid": "Papalopulu-N" }, { "family_name": "Papaioannou", "given_name": "Virginia E.", "clpid": "Papaioannou-V-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Generation of inside cells that develop into inner cell mass (ICM) and outside cells that develop into trophectoderm is central to the development of the early mouse embryo. Critical to this decision is the development of cell polarity and the associated asymmetric (differentiative) divisions of the 8-cell-stage blastomeres. The underlying molecular mechanisms for these events are not understood. As the Par3/aPKC complex has a role in establishing cellular polarity and division orientation in other systems, we explored its potential function in the developing mouse embryo. We show that both Par3 and aPKC adopt a polarized localization from the 8-cell stage onwards and that manipulating their function re-directs cell positioning and consequently influences cell fate. Injection of dsRNA against Par3 or mRNA for a dominant negative form of aPKC into a random blastomere at the 4-cell stage directs progeny of the injected cell into the inside part of the embryo. This appears to result from both an increased frequency by which such cells undertake differentiative divisions and their decreased probability of retaining outside positions. Thus, the natural spatial allocation of blastomere progeny can be over-ridden by downregulation of Par3 or aPKC, leading to a deceased tendency for them to remain outside and so develop into trophectoderm. In addition, this experimental approach illustrates a powerful means of manipulating gene expression in a specific clonal population of cells in the preimplantation embryo.", "doi": "10.1242/jcs.01666", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2005-02-01", "series_number": "3", "volume": "118", "issue": "3", "pages": "505-515" }, { "id": "authors:nntpb-86395", "collection": "authors", "collection_id": "nntpb-86395", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170350461", "type": "article", "title": "Genome-wide survey of protein kinases required for cell cycle progression", "author": [ { "family_name": "Bettencourt-Dias", "given_name": "M.", "clpid": "Bettencourt-Dias-M" }, { "family_name": "Giet", "given_name": "R.", "clpid": "Giet-R" }, { "family_name": "Sinka", "given_name": "R.", "clpid": "Sinka-R" }, { "family_name": "Mazumdar", "given_name": "A.", "clpid": "Mazumdar-A" }, { "family_name": "Lock", "given_name": "W. G.", "clpid": "Lock-W-G" }, { "family_name": "Balloux", "given_name": "F.", "clpid": "Balloux-F" }, { "family_name": "Zafiropoulos", "given_name": "P. J.", "clpid": "Zafiropoulos-P-J" }, { "family_name": "Yamaguchi", "given_name": "S.", "clpid": "Yamaguchi-S" }, { "family_name": "Winter", "given_name": "S.", "clpid": "Winter-S" }, { "family_name": "Carthew", "given_name": "R. W.", "clpid": "Carthew-R-W" }, { "family_name": "Cooper", "given_name": "M.", "clpid": "Cooper-M" }, { "family_name": "Jones", "given_name": "D.", "clpid": "Jones-D" }, { "family_name": "Frenz", "given_name": "L.", "clpid": "Frenz-L" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Cycles of protein phosphorylation are fundamental in regulating the progression of the eukaryotic cell through its division cycle. Here we test the complement of Drosophila protein kinases (kinome) for cell cycle functions after gene silencing by RNA-mediated interference. We observed cell cycle dysfunction upon downregulation of 80 out of 228 protein kinases, including most kinases that are known to regulate the division cycle. We find new enzymes with cell cycle functions; some of these have family members already known to phosphorylate microtubules, actin or their associated proteins. Additionally, depletion of several signalling kinases leads to specific mitotic aberrations, suggesting novel roles for familiar enzymes. The survey reveals the inter-digitation of systems that monitor cellular physiology, cell size, cellular stress and signalling processes with the basic cell cycle regulatory machinery.", "doi": "10.1038/nature03160", "issn": "0028-0836", "publisher": "Nature Publishing Group", "publication": "Nature", "publication_date": "2004-12-23", "series_number": "7020", "volume": "432", "issue": "7020", "pages": "980-987" }, { "id": "authors:3vrnw-g4385", "collection": "authors", "collection_id": "3vrnw-g4385", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163116265", "type": "article", "title": "The E2-C Vihar Is Required for the Correct Spatiotemporal Proteolysis of Cyclin B and Itself Undergoes Cyclical Degradation", "author": [ { "family_name": "M\u00e1th\u00e9", "given_name": "Endre", "clpid": "M\u00e1th\u00e9-E" }, { "family_name": "Kraft", "given_name": "Claudine", "clpid": "Kraft-Claudine" }, { "family_name": "Giet", "given_name": "R\u00e9gis", "clpid": "Giet-R" }, { "family_name": "De\u00e1k", "given_name": "P\u00e9ter", "clpid": "De\u00e1k-P" }, { "family_name": "Peters", "given_name": "Jan-Michael", "clpid": "Peters-Jan-Michael" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Background: Proteolytic degradation of mitotic regulatory proteins first requires these targets to be ubiquitinated. This is regulated at the level of conjugation of ubiquitin to substrates by the anaphase-promoting complex/cyclosome (APC/C) ubiquitin-protein ligase. Substrate specificity and temporal activity of the APC/C has been thought to lie primarily with its two activators, Cdc20/Fizzy and Cdh1/Fizzy-related. \n\nResults: Here, we show that reduction in the E2 ubiquitin-conjugating enzyme (UBC) of the E2-C family that is encoded by the Drosophila gene vihar (vih), by either mutation or RNAi, leads to an accumulation of cells in a metaphase-like state. Cyclin B accumulates to high levels in all mitotic vih cells, particularly at the spindle poles. Vihar E2-C is present in the cytoplasm of mitotic cells but also associates with centrosomes, and its own degradation is initiated at the metaphase-anaphase transition. Expression of destruction D box mutants of vihar in the syncytial embryo results in mitotic arrest at late anaphase. In contrast to hypomorphic mutants, Cyclin B is degraded at the spindle poles and accumulates in the equatorial region of the spindle. \n\nConclusions: In Drosophila, the Vihar E2 UBC contributes to the spatiotemporal control of Cyclin B degradation that first occurs at the spindle poles. APC/C-mediated proteolysis of Vihar E2-C autoinactivates the APC/C at the centrosome before a second wave of proteolysis to degrade Cyclin B on the rest of the spindle and elsewhere in the cell.", "doi": "10.1016/j.cub.2004.09.023", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2004-10-05", "series_number": "19", "volume": "14", "issue": "19", "pages": "1723-1733" }, { "id": "authors:97pyk-2mt35", "collection": "authors", "collection_id": "97pyk-2mt35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-150756372", "type": "article", "title": "Drosophila Klp67A is required for proper chromosome congression and segregation during meiosis I", "author": [ { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Gatt", "given_name": "Melanie K.", "clpid": "Gatt-M-K" }, { "family_name": "Riparbelli", "given_name": "Maria G.", "clpid": "Riparbelli-M-G" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Drosophila Klp67A belongs to the Kip3 subfamily of Kinesin-type microtubule catastrophe factors. In primary spermatocytes, loss of klp67A leads to defects in karyokinesis and cytokinesis. We show that these cells formed disorganised, bipolar spindles that contained increased numbers of microtubules. The kinetochore fibres were wavy and bent, whereas astral microtubules appeared abnormally robust and formed cortical bundles. Time-lapse studies revealed that during biorientation, the chromosomes in klp67A mutant cells continued to reorient for about twice as long as those in control cells. Metaphase plates were poorly defined in the mutants and often formed at non-equatorial positions. Consistent with the above abnormalities in chromosome congression, we found that in wild-type cells Klp67A associated with prometaphase/metaphase kinetochores before redistributing to the central spindle at anaphase onset. Although the timing of this redistribution of kinetochores argues against a role in anaphase chromosome segregation, dyads in the mutants disjoined but exhibited greatly diminished poleward velocities. They travelled on average at approximately 34% of the velocity of their wild-type counterparts and often decondensed at non-polar locations. Hypomorphic mutations of klp67A may lead to segregation defects.", "doi": "10.1242/jcs.01213", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2004-07-15", "series_number": "16", "volume": "117", "issue": "16", "pages": "3669-3677" }, { "id": "authors:r00k7-ecz32", "collection": "authors", "collection_id": "r00k7-ecz32", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626318", "type": "article", "title": "Mutations in sticky lead to defective organization of the contractile ring during cytokinesis and are enhanced by Rho and suppressed by Rac", "author": [ { "family_name": "D'Avino", "given_name": "Pier Paolo", "orcid": "0000-0002-4773-6950", "clpid": "D'Avino-P-P" }, { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The contractile ring is a highly dynamic structure, but how this dynamism is accomplished remains unclear. Here, we report the identification and analysis of a novel Drosophila gene, sticky (sti), essential for cytokinesis in all fly proliferating tissues. sti encodes the Drosophila orthologue of the mammalian Citron kinase. RNA interference\u2013mediated silencing of sti in cultured cells causes them to become multinucleate. Components of the contractile ring and central spindle are recruited normally in such STICKY-depleted cells that nevertheless display asymmetric furrowing and aberrant blebbing. Together with an unusual distribution of F-actin and Anillin, these phenotypes are consistent with defective organization of the contractile ring. sti shows opposite genetic interactions with Rho and Rac genes suggesting that these GTPases antagonistically regulate STICKY functions. Similar genetic evidence indicates that RacGAP50C inhibits Rac during cytokinesis. We discuss that antagonism between Rho and Rac pathways may control contractile ring dynamics during cytokinesis.", "doi": "10.1083/jcb.200402157", "pmcid": "PMC2172139", "issn": "1540-8140", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2004-07-05", "series_number": "1", "volume": "166", "issue": "1", "pages": "61-71" }, { "id": "authors:768m8-g8y91", "collection": "authors", "collection_id": "768m8-g8y91", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626417", "type": "article", "title": "Mutations in orbit/mast reveal that the central spindle is comprised of two microtubule populations, those that initiate cleavage and those that propagate furrow ingression", "author": [ { "family_name": "Inoue", "given_name": "Yoshihiro H.", "clpid": "Inoue-Yoshihiro-H" }, { "family_name": "Savoian", "given_name": "Matthew S.", "orcid": "0000-0002-2594-3879", "clpid": "Savoian-M-S" }, { "family_name": "Suzuki", "given_name": "Takao", "clpid": "Suzuki-Takao" }, { "family_name": "M\u00e1th\u00e9", "given_name": "Endre", "clpid": "M\u00e1th\u00e9-Endre" }, { "family_name": "Yamamoto", "given_name": "Masa-Toshi", "clpid": "Yamamoto-Masa-Toshi" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We address the relative roles of astral and central spindle microtubules (MTs) in cytokinesis of Drosophila melanogaster primary spermatocytes. Time-lapse imaging studies reveal that the central spindle is comprised of two MT populations, \"interior\" central spindle MTs found within the spindle envelope and \"peripheral\" astral MTs that probe the cytoplasm and initiate cleavage furrows where they contact the cortex and form overlapping bundles. The MT-associated protein Orbit/Mast/CLASP concentrates on interior rather than peripheral central spindle MTs. Interior MTs are preferentially affected in hypomorphic orbit mutants, and consequently the interior central spindle fails to form or is unstable. In contrast, peripheral MTs still probe the cortex and form regions of overlap that recruit the Pav-KLP motor and Aurora B kinase. orbit mutants have disorganized or incomplete anillin and actin rings, and although cleavage furrows initiate, they ultimately regress. Our work identifies a new function for Orbit/Mast/CLASP and identifies a novel MT population involved in cleavage furrow initiation.", "doi": "10.1083/jcb.200402052", "pmcid": "PMC2172146", "issn": "1540-8140", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2004-07-05", "series_number": "1", "volume": "166", "issue": "1", "pages": "49-60" }, { "id": "authors:s9v51-wz018", "collection": "authors", "collection_id": "s9v51-wz018", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190419-105738331", "type": "article", "title": "First Cleavage of the Mouse Embryo Responds to Change in Egg Shape at Fertilization", "author": [ { "family_name": "Gray", "given_name": "Dionne", "clpid": "Gray-D" }, { "family_name": "Plusa", "given_name": "Berenika", "clpid": "Plusa-B" }, { "family_name": "Piotrowska", "given_name": "Karolina", "clpid": "Piotrowska-Nitsche-K" }, { "family_name": "Na", "given_name": "Jie", "clpid": "Na-Jie" }, { "family_name": "Tom", "given_name": "Brian", "clpid": "Tom-B-D" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Although mouse development is regulative, the cleavage pattern of the embryo is not random 1, 2. The first cleavage tends to relate to the site of the previous meiosis 3, 4. Sperm entry might provide a second cue, but evidence for 5, 6 and against 7, 8 this is indirect and has been debated 9, 10. To resolve whether sperm entry position relates to the first cleavage, we have followed development from fertilization by time-lapse imaging. This directly showed cytokinesis passes close to the site of the previous meiosis and to both the sperm entry site and trajectory of the male pronucleus in a significant majority of eggs. We detected asymmetric distribution of Par6 protein in relation to the site of meiosis, but not sperm entry. Unexpectedly, we found the egg becomes flattened upon fertilization in an actin-mediated process. The sperm entry position tends to lie at one end of the short axis along which cleavage will pass. When we manipulated eggs to change their shape, this repositioned the cleavage plane such that eggs divided along their experimentally imposed short axis. Such manipulated eggs were able to develop to term, emphasizing the regulative nature of their development.", "doi": "10.1016/j.cub.2004.02.031", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2004-03-09", "series_number": "5", "volume": "14", "issue": "5", "pages": "397-405" }, { "id": "authors:m82d2-hmc89", "collection": "authors", "collection_id": "m82d2-hmc89", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-150756464", "type": "article", "title": "Mutations in m\u00e1kos, a Drosophila gene encoding the Cdc27 subunit of the anaphase promoting complex, enhance centrosomal defects in polo and are suppressed by mutations in twins/aar, which encodes a regulatory subunit of PP2A", "author": [ { "family_name": "De\u00e1k", "given_name": "P\u00e9ter", "clpid": "De\u00e1k-P\u00e9ter" }, { "family_name": "Donaldson", "given_name": "Mary", "clpid": "Donaldson-Mary-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The gene m\u00e1kos (mks) encodes the Drosophila counterpart of the Cdc27 subunit of the anaphase promoting complex (APC/C). Neuroblasts from third-larval-instar mks mutants arrest mitosis in a metaphase-like state but show some separation of sister chromatids. In contrast to metaphase-checkpoint-arrested cells, such mutant neuroblasts contain elevated levels not only of cyclin B but also of cyclin A. Mutations in mks enhance the reduced ability of hypomorphic polo mutant alleles to recruit and/or maintain the centrosomal antigens \u03b3-tubulin and CP190 at the spindle poles. Absence of the MPM2 epitope from the spindle poles in such double mutants suggests Polo kinase is not fully activated at this location. Thus, it appears that spindle pole functions of Polo kinase require the degradation of early mitotic targets of the APC/C, such as cyclin A, or other specific proteins. The metaphase-like arrest of mks mutants cannot be overcome by mutations in the spindle integrity checkpoint gene bub1, confirming this surveillance pathway has to operate through the APC/C. However, mutations in the twins/aar gene, which encodes the 55kDa regulatory subunit of PP2A, do suppress the mks metaphase arrest and so permit an alternative means of initiating anaphase. Thus the APC/C might normally be required to inactivate wild-type twins/aar gene product.", "doi": "10.1242/jcs.00722", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2003-10-15", "series_number": "20", "volume": "116", "issue": "20", "pages": "4147-4158" }, { "id": "authors:b0we6-byb80", "collection": "authors", "collection_id": "b0we6-byb80", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351387", "type": "article", "title": "Localization of Pavarotti-KLP in Living Drosophila Embryos Suggests Roles in Reorganizing the Cortical Cytoskeleton during the Mitotic Cycle", "author": [ { "family_name": "Minestrini", "given_name": "Gianluca", "clpid": "Minestrini-G" }, { "family_name": "Harley", "given_name": "Alyssa S.", "clpid": "Harley-A-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Pav-KLP is the Drosophila member of the MKLP1 family essential for cytokinesis. In the syncytial blastoderm embryo, GFP-Pav-KLP cyclically associates with astral, spindle, and midzone microtubules and also to actomyosin pseudocleavage furrows. As the embryo cellularizes, GFP-Pav-KLP also localizes to the leading edge of the furrows that form cells. In mononucleate cells, nuclear localization of GFP-Pav-KLP is mediated through NLS elements in its C-terminal domain. Mutants in these elements that delocalize Pav-KLP to the cytoplasm in interphase do not affect cell division. In mitotic cells, one population of wild-type GFP-Pav-KLP associates with the spindle and concentrates in the midzone at anaphase B. A second is at the cell cortex on mitotic entry and later concentrates in the region of the cleavage furrow. An ATP binding mutant does not localize to the cortex and spindle midzone but accumulates on spindle pole microtubules to which actin is recruited. This leads either to failure of the cleavage furrow to form or later defects in which daughter cells remain connected by a microtubule bridge. Together, this suggests Pav-KLP transports elements of the actomyosin cytoskeleton to plus ends of astral microtubules in the equatorial region of the cell to permit cleavage ring formation.", "doi": "10.1091/mbc.e03-04-0214", "pmcid": "PMC206997", "issn": "1059-1524", "publisher": "American Society for Cell Biology", "publication": "Molecular Biology of the Cell", "publication_date": "2003-10", "series_number": "10", "volume": "14", "issue": "10", "pages": "4028-4038" }, { "id": "authors:g6p1r-vj190", "collection": "authors", "collection_id": "g6p1r-vj190", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626522", "type": "article", "title": "Aurora A on the Mitotic Spindle Is Activated by the Way It Holds Its Partner", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "An exciting study in this issue (Bayliss et al., 2003) reveals how binding of the microtubule associated protein TPX2 to the mitotic kinase Aurora A induces a conformational change. This moves the phosphorylated activation domain into a more compact position within the kinase core, providing a better substrate binding platform and hiding the activating phosphoryl group from attack by PP1.", "doi": "10.1016/s1097-2765(03)00405-2", "issn": "1097-2765", "publisher": "Cell Press", "publication": "Molecular Cell", "publication_date": "2003-10", "series_number": "4", "volume": "12", "issue": "4", "pages": "797-799" }, { "id": "authors:rm7cw-qew41", "collection": "authors", "collection_id": "rm7cw-qew41", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140639974", "type": "article", "title": "giant nucleiis essential in the cell cycle transition from meiosis to mitosis", "author": [ { "family_name": "Renault", "given_name": "Andrew D.", "clpid": "Renault-Andrew-D" }, { "family_name": "Zhang", "given_name": "Xiao-Hua", "clpid": "Zhang-Xiao-Hua" }, { "family_name": "Alphey", "given_name": "Luke S.", "clpid": "Alphey-L-S" }, { "family_name": "Frenz", "given_name": "Lisa M.", "clpid": "Frenz-L-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Axton", "given_name": "J. Myles", "clpid": "Axton-J-M" } ], "abstract": "At the transition from meiosis to cleavage mitoses, Drosophila requires the cell cycle regulators encoded by the genes, giant nuclei (gnu), plutonium (plu) and pan gu (png). Embryos lacking Gnu protein undergo DNA replication and centrosome proliferation without chromosome condensation or mitotic segregation. We have identified the gnu gene encoding a novel phosphoprotein dephosphorylated by Protein phosphatase 1 at egg activation. Gnu is normally expressed in the nurse cells and oocyte of the ovary and is degraded during the embryonic cleavage mitoses. Ovarian death and sterility result from gnu gain of function. gnu function requires the activity of pan gu and plu.", "doi": "10.1242/dev.00501", "issn": "0950-1991", "publisher": "Company of Biologists", "publication": "Development", "publication_date": "2003-07-01", "series_number": "13", "volume": "130", "issue": "13", "pages": "2997-3005" }, { "id": "authors:3vg0j-fjs82", "collection": "authors", "collection_id": "3vg0j-fjs82", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-114539279", "type": "article", "title": "A 'marker switch' approach for targeted mutagenesis of genes in Schizosaccharomyces pombe", "author": [ { "family_name": "MacIver", "given_name": "Fiona H.", "clpid": "MacIver-F-H" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" } ], "abstract": "The completion of the Schizosaccharomyces pombe genome sequencing project has led to a dramatic acceleration of gene characterization in this system. Once a gene has been identified, the challenge then comes in using reverse genetics to generate a range of mutants in this gene of interest so that the powerful genetics and wealth of genetic backgrounds available in Sz. pombe can be exploited to study the function of the newly identified molecule. Beyond simple PCR\u2010tagging approaches, the high frequency with which illegitimate recombination occurs in Sz. pombe has made the manipulation of some loci complex, time consuming and a process of trial and error. Here we describe a simple 'marker switch' approach that enables the rapid selection of integration events at the locus of interest from an excessive background of integration at heterologous sites. We use the generation of temperature\u2010sensitive mutations in the plo1\u207a gene to validate this approach.", "doi": "10.1002/yea.983", "issn": "0749-503X", "publisher": "Wiley", "publication": "Yeast", "publication_date": "2003-05", "series_number": "7", "volume": "20", "issue": "7", "pages": "587-594" }, { "id": "authors:fsy97-3g663", "collection": "authors", "collection_id": "fsy97-3g663", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190419-105738699", "type": "article", "title": "RNA Interference by Production of Short Hairpin dsRNA in ES Cells, Their Differentiated Derivatives, and in Somatic Cell Lines", "author": [ { "family_name": "Grabarek", "given_name": "J. B.", "clpid": "Grabarek-J-B" }, { "family_name": "Wianny", "given_name": "F.", "clpid": "Wianny-F" }, { "family_name": "Plusa", "given_name": "B.", "clpid": "Plusa-B" }, { "family_name": "Zernicka-Goetz", "given_name": "M.", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "dsRNA of several hundred nucleotides in length is effective at interfering with gene expression in mouse oocytes, pre-implantation embryos, and embryonic stem (ES) cells but is not as efficient in differentiated cell lines. Here we describe a method to achieve RNA interference in totipotent and differentiated ES cells together with a wide range of other mammalian cell types that is both simple and efficient. It utilizes a linearized plasmid that directs the expression of a hairpin RNA with a 22-nucleotide-paired region. This molecule has a 13-nucleotide 5\u2032 overhang that would be subject to capping on its 5\u2032 phosphoryl group and thus differs from the ideal structure suggested for effective small interfering RNAs. Thus, it appears either that the structure of small inhibitory RNA molecules may not need to be as precise as previously thought or that such a transcript is efficiently processed to a form that is effective in interfering with gene expression.", "doi": "10.2144/03344st02", "issn": "0736-6205", "publisher": "Informa Healthcare", "publication": "BioTechniques", "publication_date": "2003-04", "series_number": "4", "volume": "34", "issue": "4", "pages": "734-744" }, { "id": "authors:n2m9t-r1s30", "collection": "authors", "collection_id": "n2m9t-r1s30", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144714140", "type": "article", "title": "Orbit/Mast, the CLASP orthologue of Drosophila, is required for asymmetric stem cell and cystocyte divisions and development of the polarised microtubule network that interconnects oocyte and nurse cells during oogenesis", "author": [ { "family_name": "M\u00e1th\u00e9", "given_name": "Endre", "clpid": "M\u00e1th\u00e9-E" }, { "family_name": "Inoue", "given_name": "Yoshihiro H.", "clpid": "Inoue-Yoshihiro-H" }, { "family_name": "Palframan", "given_name": "William", "clpid": "Palframan-W" }, { "family_name": "Brown", "given_name": "Gemma", "clpid": "Brown-Gemma" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Drosophila oocyte differentiation is preceded by the formation of a polarised 16-cell cyst from a single progenitor stem cell as a result of four rounds of asymmetric mitosis followed by incomplete cytokinesis. We show that the Orbit/Mast microtubule-associated protein is required at several stages in the formation of such polarised 16-cell cysts. In wild-type cysts, the Orbit/Mast protein not only associates with the mitotic spindle and its poles, but also with the central spindle (spindle remnant), ring canal and fusome, suggesting it participates in interactions between these structures. In orbit mutants, the stem cells and their associated fusomes are eventually lost as Orbit/Mast protein is depleted. The mitotic spindles of those cystocytes that do divide are either diminutive or monopolar, and do not make contact with the fusome. Moreover, the spindle remnants and ring canals fail to differentiate correctly in such cells and the structure of fusome is compromised. The Orbit/Mast protein thus appears to facilitate multiple interactions of the fusome with mitotic spindles and ring canals. This ensures correct growth of the fusome into a branched asymmetrically distributed organelle that is pre-determinative of 16-cell cyst formation and oocyte fate specification. Finally the Orbit/Mast protein is required during mid-oogenesis for the organisation of the polarised microtubule network inside the 16-cell cyst that ensures oocyte differentiation. The localisation of CLIP-190 to such microtubules and to the fusome is dependent upon Orbit/Mast to which it is complexed.", "doi": "10.1242/dev.00315", "issn": "0950-1991", "publisher": "Company of Biologists", "publication": "Development", "publication_date": "2003-03-01", "series_number": "5", "volume": "130", "issue": "5", "pages": "901-915" }, { "id": "authors:3h0hn-k6a23", "collection": "authors", "collection_id": "3h0hn-k6a23", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144714047", "type": "article", "title": "Drosophila dd4 mutants reveal that \u03b3TuRC is required to maintain juxtaposed half spindles in spermatocytes", "author": [ { "family_name": "Barbosa", "given_name": "Vitor", "clpid": "Barbosa-V" }, { "family_name": "Gatt", "given_name": "Melanie", "clpid": "Gatt-M-K" }, { "family_name": "Rebollo", "given_name": "Elena", "clpid": "Rebollo-Elena" }, { "family_name": "Gonzalez", "given_name": "Cayetano", "clpid": "Gonzalez-Cayetano" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The weak spindle integrity checkpoint in Drosophila spermatocytes has revealed a novel function of the \u03b3-tubulin ring complex (\u03b3TuRC) in maintaining spindle bipolarity throughout meiosis. Bipolar and bi-astral spindles could form in Drosophila mutants for dd4, the gene encoding the 91 kDa subunit of \u03b3TuRC. However, these spindles collapsed around metaphase and began to elongate as if attempting anaphase B. The microtubules of the collapsing spindle folded back on themselves, their putative plus ends forming the focused apexes of biconical figures. Cells with such spindles were unable to undergo cytokinesis. A second type of spindle, monopolar hemi-spindles, also formed as a result of either spindle collapse at an earlier stage or failure of centrosome separation. Multiple centrosome-like bodies at the foci of hemi-spindles nucleated robust asters of microtubules in the absence of detectable \u03b3-tubulin. Time-lapse imaging revealed these to be intermediates that developed into cones, structures that also had putative plus ends of microtubules focused at their tips. Unlike biconical figures, however, cones seemed to contain a central spindle-like structure at their apexes and undergo cytokinesis. We conclude that spermatocytes do not need astral microtubules nucleated by opposite poles to intersect in order to form a central spindle and a cleavage furrow.", "doi": "10.1242/jcs.00295", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2003-03-01", "series_number": "5", "volume": "116", "issue": "5", "pages": "929-941" }, { "id": "authors:x8nxb-c0g21", "collection": "authors", "collection_id": "x8nxb-c0g21", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353829", "type": "article", "title": "plo1\u207a regulates gene transcription at the M-G\u2081 interval during the fission yeast mitotic cell cycle", "author": [ { "family_name": "Anderson", "given_name": "Mark", "clpid": "Anderson-M" }, { "family_name": "Ng", "given_name": "Szu Shien", "clpid": "Ng-Szu-Shien" }, { "family_name": "Marchesi", "given_name": "Vanessa", "clpid": "Marchesi-V" }, { "family_name": "MacIver", "given_name": "Fiona H.", "clpid": "MacIver-F-H" }, { "family_name": "Stevens", "given_name": "Frances E.", "clpid": "Stevens-F-E" }, { "family_name": "Riddell", "given_name": "Tracy", "clpid": "Riddell-T" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" }, { "family_name": "McInerny", "given_name": "Christopher J.", "clpid": "McInerny-C-J" } ], "abstract": "The regulation of gene expression plays an important part in cell cycle controls. We describe the molecular machinery that co\u2010ordinates gene transcription at the M\u2013G\u2081 interval during the fission yeast mitotic cell cycle. A sequence is identified in the cdc15\u207a promoter that we call a PCB (pombe cell cycle box), which confers M\u2013G\u2081\u2010specific transcription. Sequences similar to the PCB are present in the promoters of seven other genes, spo12\u207a, cdc19\u207a, fin1\u207a, sid2\u207a, ppb1\u207a, mid1\u207a/dmf1\u207a and plo1\u207a, which we find to be transcribed at M\u2013G1. A transcription factor complex is identified that binds to the PCB sequence, which we name PBF, for PCB\u2010binding factor. Finally, we show that PBF binding activity and consequent gene transcription are regulated by the Plo1p protein kinase, thus invoking a potential auto\u2010feedback loop mechanism that regulates mitotic gene transcription and passage through septation and cytokinesis.", "doi": "10.1093/emboj/cdf564", "pmcid": "PMC131061", "issn": "1460-2075", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "2002-11-01", "series_number": "21", "volume": "21", "issue": "21", "pages": "5745-5755" }, { "id": "authors:7x20y-hr337", "collection": "authors", "collection_id": "7x20y-hr337", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190422-100408799", "type": "article", "title": "Site of the previous meiotic division defines cleavage orientation in the mouse embryo", "author": [ { "family_name": "Plusa", "given_name": "Berenika", "clpid": "Plusa-B" }, { "family_name": "Grabarek", "given_name": "Joanna B.", "clpid": "Grabarek-J-B" }, { "family_name": "Piotrowska", "given_name": "Karolina", "clpid": "Piotrowska-Nitsche-K" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "The conservation of early cleavage patterns in organisms as diverse as echinoderms and mammals suggests that even in highly regulative embryos such as the mouse, division patterns might be important for development. Indeed, the first cleavage divides the fertilized mouse egg into two cells: one cell that contributes predominantly to the embryonic part of the blastocyst, and one that contributes to the abembryonic part. Here we show, by removing, transplanting or duplicating the animal or vegetal poles of the mouse egg, that a spatial cue at the animal pole orients the plane of this initial division. Embryos with duplicated animal, but not vegetal, poles show abnormalities in chromosome segregation that compromise their development. Our results show that localized factors in the mammalian egg orient the spindle and so define the initial cleavage plane. In increased dosage, however, these factors are detrimental to the correct execution of division.", "doi": "10.1038/ncb860", "issn": "1465-7392", "publisher": "Nature Publishing Group", "publication": "Nature Cell Biology", "publication_date": "2002-10", "series_number": "10", "volume": "4", "issue": "10", "pages": "811-815" }, { "id": "authors:3g87x-0bc76", "collection": "authors", "collection_id": "3g87x-0bc76", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190422-100408907", "type": "article", "title": "Efficient delivery of dsRNA into zona-enclosed mouse oocytes and preimplantation embryos by electroporation", "author": [ { "family_name": "Grabarek", "given_name": "Joanna B.", "clpid": "Grabarek-J-B" }, { "family_name": "Plusa", "given_name": "Berenika", "clpid": "Plusa-B" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "Conditions for the electroporation of mouse oocytes and preimplantation embryos have been optimised by following the incorporation of rhodamine labeled dextran. This procedure includes a step to weaken but not remove the zona pellucida that helps achieve good survival. This approach has been applied to introduce double\u2010stranded RNA for c\u2010mos into oocytes and green fluorescent protein (GFP) into transgenic GFP\u2010expressing embryos at the 1\u2010 and 4\u2010cell stages. In both cases we were able to observe sequence\u2010specific interference with the expression of the target gene\u2014a failure of oocytes to arrest at metaphase II and a loss in the green fluorescence of embryos by the morula or blastocyst stages. These effects could be observed in multiple oocytes or embryos allowed to develop together following electroporation.", "doi": "10.1002/gene.10076", "issn": "1526-954X", "publisher": "Wiley", "publication": "Genesis", "publication_date": "2002-04", "series_number": "4", "volume": "32", "issue": "4", "pages": "269-276" }, { "id": "authors:nkb9b-j7v07", "collection": "authors", "collection_id": "nkb9b-j7v07", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144056985", "type": "article", "title": "A requirement for the Abnormal Spindle protein to organise microtubules of the central spindle for cytokinesis in Drosophila", "author": [ { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "clpid": "Riparbelli-M-G" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "do Carmo Avides", "given_name": "Maria", "clpid": "do-Carmo-Avides-M" } ], "abstract": "Drosophila abnormal spindle (asp) mutants exhibit a mitotic metaphase checkpoint arrest with abnormal spindle poles, which reflects a requirement for Asp for the integrity of microtubule organising centres (MTOCs). In male meiosis, the absence of a strong spindle integrity checkpoint enables asp mutant cells to proceed through anaphase and telophase. However, the central spindle region is not correctly organised and cells frequently fail to complete cytokinesis. This contrasts with meiosis in wild-type males where at late anaphase a dense array of microtubules forms in the central spindle region that has Asp localised at its border. We speculate that Asp is associated with the minus ends of microtubules that have been released from the spindle poles to form the central spindle. A parallel situation arises in female meiosis where Asp not only associates with the minus ends of microtubules at the acentriolar poles but also with the central spindle pole body that forms between the two tandem spindles of meiosis II. Upon fertilisation, Asp is also recruited to the MTOC that nucleates the sperm aster. Asp is required for growth of the microtubules of the sperm aster, which in asp mutants remains diminutive and so prevents migration of the pronuclei.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2002-03-01", "series_number": "5", "volume": "115", "issue": "5", "pages": "913-922" }, { "id": "authors:m8a8s-77v24", "collection": "authors", "collection_id": "m8a8s-77v24", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144136349", "type": "article", "title": "Domains of the Pavarotti kinesin-like protein that direct its subcellular distribution: effects of mislocalisation on the tubulin and actin cytoskeleton during Drosophila oogenesis", "author": [ { "family_name": "Minestrini", "given_name": "Gianluca", "clpid": "Minestrini-G" }, { "family_name": "M\u00e1th\u00e9", "given_name": "Endre", "clpid": "M\u00e1th\u00e9-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The kinesin-like protein encoded by pavarotti (Pav-KLP) is essential for cytokinesis and associates with the central part of the late mitotic spindle and interphase nuclei in somatic cells (Adams et al., 1988). Here we define regions of the molecule that regulate its subcellular localisation and study the consequences of overexpressing mutant forms of the protein during oogenesis in Drosophila. Pav-KLP normally associates with the oocyte nucleus, but when over-expressed at moderate levels, its GFP tagged form also accumulates in nurse cell nuclei. At high expression levels this leads to loss of the microfilaments that tether these nuclei, so that they block the ring canals and prevent the 'dumping' of nurse cell cytoplasm into the oocyte, which results in sterility. Localisation to these nuclei is prevented by mutations in either the conserved ATP-binding site of the motor domain or the nuclear localisation sequences in the C-terminal domain. Both such mutations lead to the formation of stable arrays of cytoplasmic microtubules and the progressive disruption of the actin cytoskeleton. The latter is evident by a breakdown of the cortical actin causing disruption of cell membranes; this breakdown ultimately results in the accumulation of cytoplasmic aggregates containing tubulin, actin and at least some of their binding proteins. Pav-KLP is also found associated with the ring canals, actin-rich structures built from remnants of the cytokinesis ring. The stalk domain alone is sufficient for the exclusive association of Pav-KLP to these structures, and this has no consequences for fertility. We discuss whether disruption of actin structures by full-length cytoplasmic forms of Pav-KLP is a consequence of the resulting stabilised cytoplasmic microtubules per se or accumulation of the motor protein at ectopic cortical sites to sequester molecules that regulate actin behaviour.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2002-02-15", "series_number": "4", "volume": "115", "issue": "4", "pages": "725-736" }, { "id": "authors:shs56-2kw11", "collection": "authors", "collection_id": "shs56-2kw11", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170352216", "type": "article", "title": "Drosophila Aurora A kinase is required to localize D-TACC to centrosomes and to regulate astral microtubules", "author": [ { "family_name": "Giet", "given_name": "R\u00e9gis", "clpid": "Giet-R" }, { "family_name": "McLean", "given_name": "Doris", "clpid": "McLean-D-A" }, { "family_name": "Descamps", "given_name": "Simon", "clpid": "Descamps-S" }, { "family_name": "Lee", "given_name": "Michael J.", "clpid": "Lee-Michael-J" }, { "family_name": "Raff", "given_name": "Jordan W.", "orcid": "0000-0002-4689-1297", "clpid": "Raff-J-W" }, { "family_name": "Prigent", "given_name": "Claude", "orcid": "0000-0001-8515-8699", "clpid": "Prigent-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Disruption of the function of the A-type Aurora kinase of Drosophila by mutation or RNAi leads to a reduction in the length of astral microtubules in syncytial embryos, larval neuroblasts, and cultured S2 cells. In neuroblasts, it can also lead to loss of an organized centrosome and its associated aster from one of the spindle poles, whereas the centrosome at the other pole has multiple centrioles. When centrosomes are present at the poles of aurA mutants or aurA RNAi spindles, they retain many antigens but are missing the Drosophila counterpart of mammalian transforming acidic coiled coil (TACC) proteins, D-TACC. We show that a subpopulation of the total Aurora A is present in a complex with D-TACC, which is a substrate for the kinase. We propose that one of the functions of Aurora A kinase is to direct centrosomal organization such that D-TACC complexed to the MSPS/XMAP215 microtubule-associated protein may be recruited, and thus modulate the behavior of astral microtubules.", "doi": "10.1083/jcb.200108135", "pmcid": "PMC2173350", "issn": "1540-8140", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2002-02-04", "series_number": "3", "volume": "156", "issue": "3", "pages": "437-451" }, { "id": "authors:r88cf-6dz76", "collection": "authors", "collection_id": "r88cf-6dz76", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123319068", "type": "article", "title": "... still cycling", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "It gave the greatest of pleasure to learn that two of our Editorial Board members, Paul Nurse and Tim Hunt, are to share this year's Nobel Prize for Physiology or Medicine together with Lee Hartwell. On behalf of the Journal of Cell Science and the Company of Biologists, for which Tim is also a Director representing the interests of the journal, I would like to congratulate each of them on this well-deserved award.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2001-11", "series_number": "22", "volume": "114", "issue": "22", "pages": "3953-3954" }, { "id": "authors:771rx-hcv87", "collection": "authors", "collection_id": "771rx-hcv87", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-140545910", "type": "article", "title": "The mitotic roles of Polo-like kinase", "author": [ { "family_name": "Donaldson", "given_name": "Mary M.", "clpid": "Donaldson-Mary-M" }, { "family_name": "Tavares", "given_name": "Alvaro A. M.", "clpid": "Tavares-\u00c1" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" }, { "family_name": "Nigg", "given_name": "Erich A.", "clpid": "Nigg-E-A" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The Polo-like protein kinases (Plks) are a conserved family of enzymes that play a variety of roles in the passage of cells through M phase (for reviews see Glover et al., 1998; Nigg, 1998). Named after the Drosophila polo gene originally identified through a recessive maternal effect lethal mutation, conserved Plk homologues have been identified in yeast, Xenopus, C. elegans and mammals. The interactions presented here represent information drawn from all these systems and integrated to form an overall picture. As with any undertaking of this type, there will be slight inconsistencies between specific roles for Plks in different species.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2001-07", "series_number": "13", "volume": "114", "issue": "13", "pages": "2357-2358" }, { "id": "authors:mcf45-c6p85", "collection": "authors", "collection_id": "mcf45-c6p85", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353935", "type": "article", "title": "Requirement of Hsp90 for centrosomal function reflects its regulation of Polo kinase stability", "author": [ { "family_name": "de C\u00e1rcer", "given_name": "Guillermo", "clpid": "de-C\u00e1rcer-G" }, { "family_name": "do Carmo Avides", "given_name": "Maria", "clpid": "do-Carmo-Avides-M" }, { "family_name": "Lallena", "given_name": "Maria Jos\u00e9", "clpid": "Lallena-M-J" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Gonzalez", "given_name": "Cayetano", "clpid": "Gonzalez-Cayetano" } ], "abstract": "We have previously shown that the molecular chaperone heat shock protein 90 (Hsp90) is required to ensure proper centrosome function in Drosophila and vertebrate cells. This observation led to the hypothesis that this chaperone could be required for the stability of one or more centrosomal proteins. We have found that one of these is Polo, a protein kinase known to regulate several aspects of cell division including centrosome maturation and function. Inhibition of Hsp90 results in the inactivation of Polo kinase activity. It also leads to a loss in the ability of cytoplasmic extracts to complement the failure of salt\u2010stripped preparations of centrosomes to nucleate microtubules. This effect can be rescued upon addition of active recombinant Polo. We also show that Polo and Hsp90 are part of a complex and conclude that stabilization of Polo is one of the mechanisms by which Hsp90 contributes to the maintenance of functional centrosomes.", "doi": "10.1093/emboj/20.11.2878", "pmcid": "PMC125474", "issn": "1460-2075", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "2001-06-01", "series_number": "11", "volume": "20", "issue": "11", "pages": "2878-2884" }, { "id": "authors:a3c7t-g2a25", "collection": "authors", "collection_id": "a3c7t-g2a25", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359292", "type": "article", "title": "Metaphase Arrest with Centromere Separation in polo Mutants of Drosophila", "author": [ { "family_name": "Donaldson", "given_name": "Mary M.", "clpid": "Donaldson-Mary-M" }, { "family_name": "Tavares", "given_name": "\u00c1lvaro A. M.", "clpid": "Tavares-\u00c1lvaro-A-M" }, { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "Deak", "given_name": "Peter", "clpid": "De\u00e1k-P\u00e9ter" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The Drosophila gene polo encodes a conserved protein kinase known to be required to organize spindle poles and for cytokinesis. Here we report two strongly hypomorphic mutations of polo that arrest cells of the larval brain at a point in metaphase when the majority of sister kinetochores have separated by between 20\u201350% of the total spindle length in intact cells. In contrast, analysis of sister chromatid separation in squashed preparations of cells indicates that some 83% of sisters remain attached. This suggests the separation seen in intact cells requires the tension produced by a functional spindle. The point of arrest corresponds to the spindle integrity checkpoint; Bub1 protein and the 3F3/2 epitope are present on the separated kinetochores and the arrest is suppressed by a bub1 mutation. The mutant mitotic spindles are anastral and have assembled upon centrosomes that are associated with Centrosomin and the abnormal spindle protein (Asp), but neither with \u03b3-tubulin nor CP190. We discuss roles for Polo kinase in recruiting centrosomal proteins and in regulating progression through the metaphase\u2013anaphase checkpoint.", "doi": "10.1083/jcb.153.4.663", "pmcid": "PMC2192380", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2001-05-07", "series_number": "4", "volume": "153", "issue": "4", "pages": "663-676" }, { "id": "authors:vv5h5-fss98", "collection": "authors", "collection_id": "vv5h5-fss98", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-122118459", "type": "article", "title": "The role of Plo1 kinase in mitotic commitment and septation in Schizosaccharomyces pombe", "author": [ { "family_name": "Tanaka", "given_name": "Kayoko", "clpid": "Tanaka-Kayoko" }, { "family_name": "Petersen", "given_name": "Janni", "clpid": "Petersen-Janni" }, { "family_name": "MacIver", "given_name": "Fiona", "clpid": "MacIver-F-H" }, { "family_name": "Mulvihill", "given_name": "Daniel P.", "clpid": "Mulvihill-D-P" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" } ], "abstract": "Plo1\u2010associated casein kinase activity peaked during mitosis before septation. Phosphatase treatment abolished this activity. Mitotic Plo1 activation had a requirement for prior activation of M\u2010phase promoting factor (MPF), suggesting that Plo1 does not act as a mitotic trigger kinase to initiate MPF activation during mitotic commitment. A link between Plo1 and the septum initiating network (SIN) has been suggested by the inability of plo1\u0394 cells to septate and the prolific septation following plo1\u207a overexpression. Interphase activation of Spg1, the G protein that modulates SIN activity, induced septation but did not stimulate Plo1\u2010associated kinase activity. Conversely, SIN inactivation did not affect the mitotic stimulation of Plo1\u2010associated kinase activity. plo1.ts4 cells formed a misshapen actin ring, but rarely septated at 36\u00b0C. Forced activation of Spg1 enabled plo1.ts4 mutant cells, but not cells with defects in the SIN component Sid2, to convert the actin ring to a septum. The ability of plo1\u207a overexpression to induce septation was severely compromised by SIN inactivation. We propose that Plo1 acts before the SIN to control septation.", "doi": "10.1093/emboj/20.6.1259", "pmcid": "PMC145531", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "2001-03-15", "series_number": "6", "volume": "20", "issue": "6", "pages": "1259-1270" }, { "id": "authors:3qa07-87d37", "collection": "authors", "collection_id": "3qa07-87d37", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359389", "type": "article", "title": "Drosophila Aurora B Kinase Is Required for Histone H3 Phosphorylation and Condensin Recruitment during Chromosome Condensation and to Organize the Central Spindle during Cytokinesis", "author": [ { "family_name": "Giet", "given_name": "R\u00e9gis", "orcid": "0000-0001-9027-5849", "clpid": "Giet-R" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Aurora/Ipl1-related kinases are a conserved family of enzymes that have multiple functions during mitotic progression. Although it has been possible to use conventional genetic analysis to dissect the function of aurora, the founding family member in Drosophila (Glover, D.M., M.H. Leibowitz, D.A. McLean, and H. Parry. 1995. Cell. 81:95\u2013105), the lack of mutations in a second aurora-like kinase gene, aurora B, precluded this approach. We now show that depleting Aurora B kinase using double-stranded RNA interference in cultured Drosophila cells results in polyploidy. aurora B encodes a passenger protein that associates first with condensing chromatin, concentrates at centromeres, and then relocates onto the central spindle at anaphase. Cells depleted of the Aurora B kinase show only partial chromosome condensation at mitosis. This is associated with a reduction in levels of the serine 10 phosphorylated form of histone H3 and a failure to recruit the Barren condensin protein onto chromosomes. These defects are associated with abnormal segregation resulting from lagging chromatids and extensive chromatin bridging at anaphase, similar to the phenotype of barren mutants (Bhat, M.A., A.V. Philp, D.M. Glover, and H.J. Bellen. 1996. Cell. 87:1103\u20131114.). The majority of treated cells also fail to undertake cytokinesis and show a reduced density of microtubules in the central region of the spindle. This is accompanied by a failure to correctly localize the Pavarotti kinesin-like protein, essential for this process. We discuss these conserved functions of Aurora B kinase in chromosome transmission and cytokinesis.", "doi": "10.1083/jcb.152.4.669", "pmcid": "PMC2195771", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2001-02-12", "series_number": "4", "volume": "152", "issue": "4", "pages": "669-682" }, { "id": "authors:kzajf-9qa35", "collection": "authors", "collection_id": "kzajf-9qa35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353101", "type": "article", "title": "Mutation of a Drosophila gamma tubulin ring complex subunit encoded by discs degenerate-4 differentially disrupts centrosomal protein localization", "author": [ { "family_name": "Barbosa", "given_name": "Vitor", "clpid": "Barbosa-V" }, { "family_name": "Yamamoto", "given_name": "Rochele R.", "clpid": "Yamamoto-Rochele-R" }, { "family_name": "Henderson", "given_name": "Daryl S.", "clpid": "Henderson-D-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have cloned the Drosophila gene discs degenerate-4 (dd4) and find that it encodes a component of the \u03b3-tubulin ring complex (\u03b3TuRC) homologous to Spc98 of budding yeast. This provides the first opportunity to study decreased function of a member of the \u03b3-tubulin ring complex, other than \u03b3-tubulin itself, in a metazoan cell. \u03b3-tubulin is no longer at the centrosomes but is dispersed throughout dd4 cells and yet bipolar metaphase spindles do form, although these have a dramatically decreased density of microtubules. Centrosomin (CNN) remains in broad discrete bodies but only at the focused poles of such spindles, whereas Asp (abnormal spindleprotein) is always present at the presumptive minus ends of microtubules, whether or not they are focused. This is consistent with the proposed role of Asp in coordinating the nucleation of mitotic microtubule organizing centers. The centrosome associated protein CP190 is partially lost from the spindle poles in dd4cells supporting a weak interaction with \u03b3-tubulin, and the displaced protein accumulates in the vicinity of chromosomes. Electron microscopy indicates not only that the poles of dd4 cells have irregular amounts of pericentriolar material, but also that they can have abnormal centrioles. In six dd4 cells subjected to serial sectioning centrioles were missing from one of the two poles. This suggests that in addition to its role in nucleating cytoplasmic and spindle microtubules, the \u03b3TuRC is also essential to the structure of centrioles and the separation of centrosomes.", "doi": "10.1101/gad.182800", "pmcid": "PMC317135", "issn": "0890-9369", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Genes and Development", "publication_date": "2000-12-15", "series_number": "24", "volume": "14", "issue": "24", "pages": "3126-3139" }, { "id": "authors:ywdfw-den03", "collection": "authors", "collection_id": "ywdfw-den03", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144315567", "type": "article", "title": "The Drosophila mus101 gene, which links DNA repair, replication and condensation of heterochromatin in mitosis, encodes a protein with seven BRCA1 C-terminus domains", "author": [ { "family_name": "Yamamoto", "given_name": "Rochelle R.", "clpid": "Yamamoto-Rochelle-R" }, { "family_name": "Axton", "given_name": "J. Myles", "clpid": "Axton-J-M" }, { "family_name": "Yamamoto", "given_name": "Yutaka", "clpid": "Yamamoto-Yutaka" }, { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Henderson", "given_name": "Daryl S.", "clpid": "Henderson-D-S" } ], "abstract": "The mutagen-sensitive-101 (mus101) gene of Drosophila melanogaster was first identified 25 years ago through mutations conferring larval hypersensitivity to DNA-damaging agents. Other alleles of mus101 causing different phenotypes were later isolated: a female sterile allele results in a defect in a tissue-specific form of DNA synthesis (chorion gene amplification) and lethal alleles cause mitotic chromosome instability that can be observed genetically and cytologically. The latter phenotype presents as a striking failure of mitotic chromosomes of larval neuroblasts to undergo condensation of pericentric heterochromatic regions, as we show for a newly described mutant carrying lethal allele mus101^(lcd). To gain further insight into the function of the Mus101 protein we have molecularly cloned the gene using a positional cloning strategy. We report here that mus101 encodes a member of the BRCT (BRCA1 C terminus) domain superfamily of proteins implicated in DNA repair and cell cycle checkpoint control. Mus101, which contains seven BRCT domains distributed throughout its length, is most similar to human TopBP1, a protein identified through its in vitro association with DNA topoisomerase IIbeta. Mus101 also shares sequence similarity with the fission yeast Rad4/Cut5 protein required for repair, replication, and checkpoint control, suggesting that the two proteins may be functional homologs.", "pmcid": "PMC1461266", "issn": "0016-6731", "publisher": "Genetics Society of America", "publication": "Genetics", "publication_date": "2000-10", "series_number": "2", "volume": "156", "issue": "2", "pages": "711-721" }, { "id": "authors:ysz9x-bf279", "collection": "authors", "collection_id": "ysz9x-bf279", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163116379", "type": "article", "title": "The SCF ubiquitin ligase protein Slimb regulates centrosome duplication in Drosophila", "author": [ { "family_name": "Wojcik", "given_name": "Edward J.", "clpid": "Wojcik-E-J" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hays", "given_name": "Thomas S.", "clpid": "Hays-T-S" } ], "abstract": "The duplication of the centrosome is a key event in the cell-division cycle. Although defects in centrosome duplication are thought to contribute to genomic instability [1], [2], [3] and are a hallmark of certain transformed cells and human cancer [4], [5], [6], the mechanism responsible for centrosome duplication is not understood. Recent experiments have established that centrosome duplication requires the activity of cyclin-dependent kinase 2 (Cdk2) and cyclins E and A [7], [8], [9]. The stability of cyclin E is regulated by the ubiquitin ligase SCF, which is a protein complex composed of Skp1, Cdc53 (Cullin) and F-box proteins [10], [11], [12]. The Skp1 and Cullin components have been detected on mammalian centrosomes, and shown to be essential for centrosome duplication and separation in Xenopus[13]. Here, we report that Slimb, an F-box protein that targets proteins to the SCFcomplex [14], [15], plays a role in limiting centrosome replication. We found that, in the fruit fly Drosophila, the hypomorphic mutation slimbcrd causes the appearance of additional centrosomes and mitotic defects in mutant larval neuroblasts.", "doi": "10.1016/s0960-9822(00)00703-x", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "2000-09-14", "series_number": "18", "volume": "10", "issue": "18", "pages": "1131-1134" }, { "id": "authors:k87qk-6n703", "collection": "authors", "collection_id": "k87qk-6n703", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-153559731", "type": "article", "title": "Failure of pronuclear migration and repeated divisions of polar body nuclei associated with MTOC defects in polo eggs of Drosophila", "author": [ { "family_name": "Riparbelli", "given_name": "M. G.", "clpid": "Riparbelli-M-G" }, { "family_name": "Callaini", "given_name": "G.", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The meiotic spindle of Drosophila oocytes is acentriolar but develops an unusual central microtubule organising centre (MTOC) at the end of meiosis I. In polo oocytes, this common central pole for the two tandem spindles of meiosis II was poorly organised and in contrast to wild-type failed to maintain its associated Pav-KLP motor protein. Furthermore, the polar body nuclei failed to arrest at metaphase, and the four products of female meiosis all underwent repeated haploid division cycles on anastral spindles. This was linked to a failure to form the astral array of microtubules with which the polar body chromosomes are normally associated. The MTOC associated with the male pronucleus was also defective in polo eggs, and the sperm aster did not grow. Migration of the female pronucleus did not take place and so a gonomeric spindle could not form. We discuss these findings in relation to the known roles of polo like kinases in regulating the behaviour of MTOCs.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2000-09", "series_number": "18", "volume": "113", "issue": "18", "pages": "3341-3350" }, { "id": "authors:mwx86-kq232", "collection": "authors", "collection_id": "mwx86-kq232", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-153558889", "type": "article", "title": "A new genetic method for isolating functionally interacting genes: high plo1\u207a-dependent mutants and their suppressors define genes in mitotic and septation pathways in fission yeast", "author": [ { "family_name": "Cullen", "given_name": "C. Fiona", "clpid": "Cullen-C-F" }, { "family_name": "May", "given_name": "Karen M.", "clpid": "May-Karen-M" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" } ], "abstract": "We describe a general genetic method to identify genes encoding proteins that functionally interact with and/or are good candidates for downstream targets of a particular gene product. The screen identifies mutants whose growth depends on high levels of expression of that gene. We apply this to the plo1\u207a gene that encodes a fission yeast homologue of the polo-like kinases. plo1\u207a regulates both spindle formation and septation. We have isolated 17 high plo1\u207a-dependent (pld) mutants that show defects in mitosis or septation. Three mutants show a mitotic arrest phenotype. Among the 14 pld mutants with septation defects, 12 mapped to known loci: cdc7, cdc15, cdc11 spg1, and sid2. One of the pld mutants, cdc7-PD1, was selected for suppressor analysis. As multicopy suppressors, we isolated four known genes involved in septation in fission yeast: spg1\u207a, sce3\u207a, cdc8\u207a, and rho1\u207a, and two previously uncharacterized genes, mpd1\u207a and mpd2\u207a. mpd1\u207a exhibits high homology to phosphatidylinositol 4-phosphate 5-kinase, while mpd2\u207a resembles Saccharomyces cerevisiae SMY2; both proteins are involved in the regulation of actin-mediated processes. As chromosomal suppressors of cdc7-PD1, we isolated mutations of cdc16 that resulted in multiseptation without nuclear division. cdc16\u207a, dma1\u207a, byr3\u207a, byr4\u207a and a truncated form of the cdc7 gene were isolated by complementation of one of these cdc16 mutations. These results demonstrate that screening for high dose-dependent mutants and their suppressors is an effective approach to identify functionally interacting genes.", "pmcid": "PMC1461180", "issn": "0016-6731", "publisher": "Genetics Society of America", "publication": "Genetics", "publication_date": "2000-08", "series_number": "4", "volume": "155", "issue": "4", "pages": "1521-1534" }, { "id": "authors:94ybx-b7g15", "collection": "authors", "collection_id": "94ybx-b7g15", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359484", "type": "article", "title": "Orbit, a Novel Microtubule-Associated Protein Essential for Mitosis in Drosophila melanogaster", "author": [ { "family_name": "Inoue", "given_name": "Yoshihiro H.", "clpid": "Inoue-Yoshihiro-H" }, { "family_name": "do Carmo Avides", "given_name": "Maria", "clpid": "do-Carmo-Avides-M" }, { "family_name": "Shiraki", "given_name": "Michina", "clpid": "Shiraki-Michina" }, { "family_name": "Deak", "given_name": "Peter", "clpid": "De\u00e1k-P\u00e9ter" }, { "family_name": "Yamaguchi", "given_name": "Masamitsu", "clpid": "Yamaguchi-Masamitsu" }, { "family_name": "Nishimoto", "given_name": "Yoshio", "clpid": "Nishimoto-Yoshio" }, { "family_name": "Matsukage", "given_name": "Akio", "clpid": "Matsukage-Akio" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We describe a Drosophila gene, orbit, that encodes a conserved 165-kD microtubule-associated protein (MAP) with GTP binding motifs. Hypomorphic mutations in orbit lead to a maternal effect resulting in branched and bent mitotic spindles in the syncytial embryo. In the larval central nervous system, such mutants have an elevated mitotic index with some mitotic cells showing an increase in ploidy. Amorphic alleles show late lethality and greater frequencies of hyperploid mitotic cells. The presence of cells in the hypomorphic mutant in which the chromosomes can be arranged, either in a circular metaphase or an anaphase-like configuration on monopolar spindles, suggests that polyploidy arises through spindle and chromosome segregation defects rather than defects in cytokinesis. A role for the Orbit protein in regulating microtubule behavior in mitosis is suggested by its association with microtubules throughout the spindle at all mitotic stages, by its copurification with microtubules from embryonic extracts, and by the finding that the Orbit protein directly binds to MAP-free microtubules in a GTP-dependent manner.", "doi": "10.1083/jcb.149.1.153", "pmcid": "PMC2175100", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "2000-04-03", "series_number": "1", "volume": "149", "issue": "1", "pages": "153-166" }, { "id": "authors:03ntq-zas76", "collection": "authors", "collection_id": "03ntq-zas76", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-153558029", "type": "article", "title": "Mutual correction of faulty PCNA subunits in temperature-sensitive lethal mus209 mutants of Drosophila melanogaster", "author": [ { "family_name": "Henderson", "given_name": "Daryl S.", "clpid": "Henderson-D-S" }, { "family_name": "Wiegand", "given_name": "Ulrich K.", "clpid": "Wiegand-U-K" }, { "family_name": "Norman", "given_name": "David G.", "clpid": "Norman-D-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Proliferating cell nuclear antigen (PCNA) functions in DNA replication as a processivity factor for polymerases delta and epsilon, and in multiple DNA repair processes. We describe two temperature-sensitive lethal alleles (mus209^(B1) and mus209^(2735)) of the Drosophila PCNA gene that, at temperatures permissive for growth, result in hypersensitivity to DNA-damaging agents, suppression of position-effect variegation, and female sterility in which ovaries are underdeveloped and do not produce eggs. We show by mosaic analysis that the sterility of mus209(B1) is partly due to a failure of germ-line cells to proliferate. Strikingly, mus209^(B1) and mus209^(2735) interact to restore partial fertility to heteroallelic females, revealing additional roles for PCNA in ovarian development, meiotic recombination, and embryogenesis. We further show that, although mus209^(B1) and mus209^(2735) homozygotes are each defective in repair of transposase-induced DNA double-strand breaks in somatic cells, this defect is substantially reversed in the heteroallelic mutant genotype. These novel mutations map to adjacent sites on the three-dimensional structure of PCNA, which was unexpected in the context of this observed interallelic complementation. These mutations, as well as four others we describe, reveal new relationships between the structure and function of PCNA.", "pmcid": "PMC1461035", "issn": "0016-6731", "publisher": "Genetics Society of America", "publication": "Genetics", "publication_date": "2000-04", "series_number": "4", "volume": "154", "issue": "4", "pages": "1721-1733" }, { "id": "authors:p6t04-qad48", "collection": "authors", "collection_id": "p6t04-qad48", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200810-151627415", "type": "article", "title": "New doors to open...and so many!", "author": [ { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The pursuit of science is a wonderful journey of discovery along which there are a myriad of avenues to be explored. There have always been so many objects of fascination, so many questions to ask along the way, so many possibilities to understand new principles, that making the decision about which problem to address and then having the self-discipline to explore it in depth challenge all who practice the art. How then are we, as cell biologists, to cope with the mountain of information that is accumulating as we enter the twenty-first century?", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "2000-02", "series_number": "3", "volume": "113", "issue": "3", "pages": "359-360" }, { "id": "authors:st2ek-ep187", "collection": "authors", "collection_id": "st2ek-ep187", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359580", "type": "article", "title": "mini spindles: A Gene Encoding a Conserved Microtubule-Associated Protein Required for the Integrity of the Mitotic Spindle in Drosophila", "author": [ { "family_name": "Cullen", "given_name": "C. Fiona", "clpid": "Cullen-C-F" }, { "family_name": "De\u00e1k", "given_name": "Peter", "clpid": "De\u00e1k-P\u00e9ter" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" } ], "abstract": "We describe a new Drosophila gene, mini spindles (msps) identified in a cytological screen for mitotic mutant. Mutation in msps disrupts the structural integrity of the mitotic spindle, resulting in the formation of one or more small additional spindles in diploid cells. Nucleation of microtubules from centrosomes, metaphase alignment of chromosomes, or the focusing of spindle poles appears much less affected. The msps gene encodes a 227-kD protein with high similarity to the vertebrate microtubule-associated proteins (MAPs), human TOGp and Xenopus XMAP215, and with limited similarity to the Dis1 and STU2 proteins from fission yeast and budding yeast. Consistent with their sequence similarity, Msps protein also associates with microtubules in vitro. In the embryonic division cycles, Msps protein localizes to centrosomal regions at all mitotic stages, and spreads over the spindles during metaphase and anaphase. The absence of centrosomal staining in interphase of the cellularized embryos suggests that the interactions between Msps protein and microtubules or centrosomes may be regulated during the cell cycle.", "doi": "10.1083/jcb.146.5.1005", "pmcid": "PMC2169485", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "1999-09-06", "series_number": "5", "volume": "146", "issue": "5", "pages": "1005-1018" }, { "id": "authors:wsjtb-11q06", "collection": "authors", "collection_id": "wsjtb-11q06", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170354035", "type": "article", "title": "Plo1 Kinase Recruitment to the Spindle Pole Body and Its Role in Cell Division in Schizosaccharomyces pombe", "author": [ { "family_name": "Mulvihill", "given_name": "Daniel P.", "clpid": "Mulvihill-D-P" }, { "family_name": "Petersen", "given_name": "Janni", "clpid": "Petersen-Janni" }, { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" } ], "abstract": "Polo kinases execute multiple roles during cell division. The fission yeast polo related kinase Plo1 is required to assemble the mitotic spindle, the prophase actin ring that predicts the site for cytokinesis and for septation after the completion of mitosis (Ohkuraet al., 1995; Bahler et al., 1998). We show that Plo1 associates with the mitotic but not interphase spindle pole body (SPB). SPB association of Plo1 is the earliest fission yeast mitotic event recorded to date. SPB association is strong from mitotic commitment to early anaphase B, after which the Plo1 signal becomes very weak and finally disappears upon spindle breakdown. SPB association of Plo1 requires mitosis-promoting factor (MPF) activity, whereas its disassociation requires the activity of the anaphase-promoting complex. The stf1.1 mutation bypasses the usual requirement for the MPF activator Cdc25 (Hudson et al., 1990). Significantly, Plo1 associates inappropriately with the interphase SPB of stf1.1 cells. These data are consistent with the emerging theme from many systems that polo kinases participate in the regulation of MPF to determine the timing of commitment to mitosis and may indicate that pole association is a key aspect of Plo1 function. Plo1 does not associate with the SPB when septation is inappropriately driven by deregulation of the Spg1 pathway and remains SPB associated if septation occurs in the presence of a spindle. Thus, neither Plo1 recruitment to nor its departure from the SPB are required for septation; however, overexpression of plo1\u207a activates the Spg1 pathway and causes transient Cdc7 recruitment to the SPB and multiple rounds of septation", "doi": "10.1091/mbc.10.8.2771", "pmcid": "PMC25513", "issn": "1059-1524", "publisher": "American Society for Cell Biology", "publication": "Molecular Biology of the Cell", "publication_date": "1999-08", "series_number": "8", "volume": "10", "issue": "8", "pages": "2771-2785" }, { "id": "authors:tvvhr-1yy86", "collection": "authors", "collection_id": "tvvhr-1yy86", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-153617168", "type": "article", "title": "Abnormal Spindle Protein, Asp, and the Integrity of Mitotic Centrosomal Microtubule Organizing Centers", "author": [ { "family_name": "do Carmo Avides", "given_name": "Maria", "clpid": "do-Carmo-Avides-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The product of the abnormal spindle (asp) gene was found to be an asymmetrically localized component of the centrosome during mitosis, required to focus the poles of the mitotic spindle in vivo. Removing Asp protein function from Drosophila melanogaster embryo extracts, either by mutation or immunodepletion, resulted in loss of their ability to restore microtubule-organizing center activity to salt-stripped centrosome preparations. This was corrected by addition of purified Asp protein. Thus, Asp appears to hold together the microtubule-nucleating \u03b3-tubulin ring complexes that organize the mitotic centrosome.", "doi": "10.1126/science.283.5408.1733", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "1999-03-12", "series_number": "5408", "volume": "283", "issue": "5408", "pages": "1733-1735" }, { "id": "authors:n4sed-v9122", "collection": "authors", "collection_id": "n4sed-v9122", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353198", "type": "article", "title": "Polo-like kinases: a team that plays throughout mitosis", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" }, { "family_name": "Tavares", "given_name": "\u00c1lvaro A. M.", "clpid": "Tavares-\u00c1" } ], "abstract": "When the first mutant allele of the Drosophila genepolo was first characterized over 10 years ago, attention focused on the defects that centrosome behavior exhibited at various stages of development (Sunkel and Glover 1988). The subsequent realization that the serine-threonine kinase it encodes is highly conserved from yeasts to humans has provoked a flurry of investigation into the function of the enzyme. A role for the polo-like kinases (plks) in regulating centrosome behavior has been borne out in several organisms, and the enzymes have attracted further attention recently with the realization that they regulate multiple stages of mitotic progression. In this article we review the current status of our understanding of the functions of plks from the time of commitment to M phase in the activation of Cdc25, through the activation of the anaphase promoting complex (APC), to the regulation of late mitotic events essential for cytokinesis. We discuss how to reconcile the sometimes apparently disparate observations made upon plk function in different organisms.", "doi": "10.1101/gad.12.24.3777", "issn": "0890-9369", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Genes and Development", "publication_date": "1998-12-15", "series_number": "24", "volume": "12", "issue": "24", "pages": "3777-3787" }, { "id": "authors:ge56g-h5h39", "collection": "authors", "collection_id": "ge56g-h5h39", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190422-101736448", "type": "article", "title": "Mouse polo-like kinase 1 associates with the acentriolar spindle poles, meiotic chromosomes and spindle midzone during oocyte maturation", "author": [ { "family_name": "Wianny", "given_name": "Florence", "clpid": "Wianny-F" }, { "family_name": "Tavares", "given_name": "\u00c1lvaro", "clpid": "Tavares-\u00c1" }, { "family_name": "Evans", "given_name": "Martin J.", "clpid": "Eans-M-J" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zernicka-Goetz", "given_name": "Magdalena", "orcid": "0000-0002-7004-2471", "clpid": "Zernicka-Goetz-M" } ], "abstract": "We have examined the dynamics of the localisation of the polo-like kinase 1 (Plk1) during maturation of the mouse oocyte. Levels of Plk1 protein increase following germinal vesicle breakdown, at which time the enzyme begins to accumulate at discrete positions on the condensing chromosomes and, subsequently, at the poles of the meiotic spindle, which moves towards the cortex of the egg. Interestingly, at metaphase in both meiotic divisions, Plk1 shows a punctate localisation along the broad spindle poles. Moreover, the punctate distribution of Plk1 on the meiotic chromosomes appears at early anaphase to correspond to the centromeric regions. The protein relocates to the spindle midzone during late anaphase and then associates with the midbody at telophase. We have confirmed the specific pattern of immuno-localisation seen in fixed preparations by observing the distribution of Plk1 tagged with green fluorescent protein in living oocytes. We discuss the localisation of the enzyme in light of the structure of the spindle poles, which are known to lack centrioles, and the highly asymmetric nature of the meiotic divisions.", "doi": "10.1007/s004120050327", "issn": "0009-5915", "publisher": "Springer", "publication": "Chromosoma", "publication_date": "1998-12", "series_number": "6-7", "volume": "107", "issue": "6-7", "pages": "430-439" }, { "id": "authors:k54rs-cpk66", "collection": "authors", "collection_id": "k54rs-cpk66", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359671", "type": "article", "title": "Drosophila Polo Kinase Is Required for Cytokinesis", "author": [ { "family_name": "Carmena", "given_name": "Mar", "orcid": "0000-0002-2352-1066", "clpid": "Carmena-M" }, { "family_name": "Riparbelli", "given_name": "Maria Giovanna", "clpid": "Riparbelli-M-G" }, { "family_name": "Minestrini", "given_name": "Gianluca", "clpid": "Minestrini-G" }, { "family_name": "Tavares", "given_name": "\u00c1lvaro A.", "clpid": "Tavares-\u00c1lvaro-A-M" }, { "family_name": "Adams", "given_name": "Richard", "clpid": "Adams-Richard-R" }, { "family_name": "Callaini", "given_name": "Giuliano", "orcid": "0000-0003-2252-0309", "clpid": "Callaini-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "A number of lines of evidence point to a predominance of cytokinesis defects in spermatogenesis in hypomorphic alleles of the Drosophila polo gene. In the pre-meiotic mitoses, cytokinesis defects result in cysts of primary spermatocytes with reduced numbers of cells that can contain multiple centrosomes. These are connected by a correspondingly reduced number of ring canals, structures formed by the stabilization of the cleavage furrow. The earliest defects during the meiotic divisions are a failure to form the correct mid-zone and mid-body structures at telophase. This is accompanied by a failure to correctly localize the Pavarotti kinesin- like protein that functions in cytokinesis, and of the septin Peanut and of actin to be incorporated into a contractile ring. In spite of these defects, cyclin B is degraded and the cells exit M phase. The resulting spermatids are frequently binuclear or tetranuclear, in which case they develop either two or four axonemes, respectively. A significant proportion of spermatids in which cytokinesis has failed may also show the segregation defects previously ascribed to polo1 mutants. We discuss these findings in respect to conserved functions for the Polo-like kinases in regulating progression through M phase, including the earliest events of cytokinesis.", "doi": "10.1083/jcb.143.3.659", "pmcid": "PMC2148135", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "1998-11-02", "series_number": "3", "volume": "143", "issue": "3", "pages": "659-671" }, { "id": "authors:zjvdg-sjf31", "collection": "authors", "collection_id": "zjvdg-sjf31", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626644", "type": "article", "title": "PCNA binding proteins in Drosophila melanogaster : the analysis of a conserved PCNA binding domain", "author": [ { "family_name": "Warbrick", "given_name": "Emma", "clpid": "Warbrick-Emma" }, { "family_name": "Heatherington", "given_name": "Wayne", "clpid": "Heatherington-W" }, { "family_name": "Lane", "given_name": "David P.", "clpid": "Lane-D-P" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The eukaryotic polymerase processivity factor, PCNA, interacts with cell cycle regulatory proteins such as p21^(WAF1/Cip1) and Gadd45, as well as with proteins involved in the mechanics of DNA repair and replication. A conserved PCNA-binding motif is found in a subset of PCNA-interacting proteins, including p21, suggesting that the regulation of these interactions is important for the co-ordination of DNA replication and repair. We have identified several classes of protein which bind to Drosophila PCNA. Two of these proteins contain the consensus PCNA-binding domain: one is the Dacapo protein, a Drosophila homologue of p21^(WAF1/Cip1), and the second is the transposase encoded by the Pogo DNA transposon. A conserved PCNA-binding domain is also present in a human relative of Pogo, named Tigger, suggesting that this domain has a functional role in this class of transposable element. This raises interesting possibilities for a novel method of transposition in which the transposase might be targeted to replicating DNA. Finally, we have investigated the use of this conserved PCNAbinding domain as a predictor of PCNA-binding capacity.", "doi": "10.1093/nar/26.17.3925", "pmcid": "PMC147798", "issn": "1362-4962", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1998-09-01", "series_number": "17", "volume": "26", "issue": "17", "pages": "3925-3932" }, { "id": "authors:ymbtw-4hc36", "collection": "authors", "collection_id": "ymbtw-4hc36", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353322", "type": "article", "title": "pavarotti encodes a kinesin-like protein required to organize the central spindle and contractile ring for\u00a0cytokinesis", "author": [ { "family_name": "Adams", "given_name": "Richard R.", "clpid": "Adams-Richard-R" }, { "family_name": "Tavares", "given_name": "\u00c1lvaro A. M.", "clpid": "Tavares-\u00c1" }, { "family_name": "Salzberg", "given_name": "Adi", "clpid": "Salzberg-Adi" }, { "family_name": "Bellen", "given_name": "Hugo J.", "clpid": "Bellen-H-J" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Mutations in the Drosophila gene pavarotti result in the formation of abnormally large cells in the embryonic nervous system. In mitotic cycle 16, cells of pav mutant embryos undergo normal anaphase but then develop an abnormal telophase spindle and fail to undertake cytokinesis. We show that the septin Peanut, actin, and the actin-associated protein Anillin, do not become correctly localized in pav mutants. pav encodes a kinesin-like protein, PAV\u2013KLP, related to the mammalian MKLP-1. In cellularized embryos, the protein is localized to centrosomes early in mitosis, and to the midbody region of the spindle in late anaphase and telophase. We show that Polo kinase associates with PAV\u2013KLP with which it shows an overlapping pattern of subcellular localization during the mitotic cycle and this distribution is disrupted in pavmutants. We suggest that PAV\u2013KLP is required both to establish the structure of the telophase spindle to provide a framework for the assembly of the contractile ring, and to mobilize mitotic regulator proteins.", "doi": "10.1101/gad.12.10.1483", "pmcid": "PMC316841", "issn": "0890-9369", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Genes and Development", "publication_date": "1998-05-15", "series_number": "10", "volume": "12", "issue": "10", "pages": "1483-1494" }, { "id": "authors:dq43m-4xd97", "collection": "authors", "collection_id": "dq43m-4xd97", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-105914160", "type": "article", "title": "P-element insertion alleles of essential genes on the third chromosome of Drosophila melanogaster: correlation of physical and cytogenetic maps in chromosomal region 86E-87F", "author": [ { "family_name": "De\u00e1k", "given_name": "P\u00e9ter", "clpid": "De\u00e1k-P\u00e9ter" }, { "family_name": "Omar", "given_name": "Mahmoud M.", "clpid": "Omar-Mahmoud-M" }, { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "P\u00e1l", "given_name": "Margit", "clpid": "P\u00e1l-Margit" }, { "family_name": "Komonyi", "given_name": "Orb\u00e1n", "clpid": "Komonyi-Orb\u00e1n" }, { "family_name": "Szidonya", "given_name": "J\u00e1nos", "clpid": "Szidonya-J\u00e1nos" }, { "family_name": "Mar\u00f3y", "given_name": "P\u00e9ter", "clpid": "Mar\u00f3y-P\u00e9ter" }, { "family_name": "Zhang", "given_name": "Yong", "clpid": "Zhang-Yong" }, { "family_name": "Ashburner", "given_name": "Michael", "clpid": "Ashburner-M" }, { "family_name": "Benos", "given_name": "Panayiotis", "clpid": "Benos-P" }, { "family_name": "Savakis", "given_name": "Charalambos", "clpid": "Savakis-C" }, { "family_name": "Siden-Kiamos", "given_name": "Inga", "clpid": "Siden-Kiamos-I" }, { "family_name": "Louis", "given_name": "Christos", "clpid": "Louis-Christos" }, { "family_name": "Bolshakov", "given_name": "Viacheslav N.", "clpid": "Bolshakov-V-N" }, { "family_name": "Kafatos", "given_name": "Fotis C.", "clpid": "Kafatos-F-C" }, { "family_name": "Madueno", "given_name": "Encarnaci\u00f3n", "clpid": "Madueno-Encarnaci\u00f3n" }, { "family_name": "Modolell", "given_name": "Juan", "clpid": "Modolell-Juan" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have established a collection of 2460 lethal or semi-lethal mutant lines using a procedure thought to insert single P elements into vital genes on the third chromosome of Drosophila melanogaster. More than 1200 randomly selected lines were examined by in situ hybridization and 90% found to contain single insertions at sites that mark 89% of all lettered subdivisions of the Bridges' map. A set of chromosomal deficiencies that collectively uncover approximately 25% of the euchromatin of chromosome 3 reveal lethal mutations in 468 lines corresponding to 145 complementation groups. We undertook a detailed analysis of the cytogenetic interval 86E-87F and identified 87 P-element-induced mutations falling into 38 complementation groups, 16 of which correspond to previously known genes. Twenty-one of these 38 complementation groups have at least one allele that has a P-element insertion at a position consistent with the cytogenetics of the locus. We have rescued P elements and flanking chromosomal sequences from the 86E-87F region in 35 lines with either lethal or genetically silent P insertions, and used these as probes to identify cosmids and P1 clones from the Drosophila genome projects. This has tied together the physical and genetic maps and has linked 44 previously identified cosmid contigs into seven \"super-contigs\" that span the interval. STS data for sequences flanking one side of the P-element insertions in 49 lines has identified insertions in the alphagamma element at 87C, two known transposable elements, and the open reading frames of seven putative single copy genes. These correspond to five known genes in this interval, and two genes identified by the homology of their predicted products to known proteins from other organisms.", "pmcid": "PMC1208341", "issn": "0016-6731", "publisher": "Genetics Society of America", "publication": "Genetics", "publication_date": "1997-12", "series_number": "4", "volume": "147", "issue": "4", "pages": "1697-1722" }, { "id": "authors:kpz24-hzp04", "collection": "authors", "collection_id": "kpz24-hzp04", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-105915082", "type": "article", "title": "P-element insertion alleles of essential genes on the third chromosome of Drosophila melanogaster: mutations affecting embryonic PNS development", "author": [ { "family_name": "Salzberg", "given_name": "Adi", "clpid": "Salzberg-Adi" }, { "family_name": "Prokopenko", "given_name": "Sergei N.", "clpid": "Prokopenko-S-N" }, { "family_name": "He", "given_name": "Yuchun", "clpid": "He-Yuchun" }, { "family_name": "Tsai", "given_name": "Peter", "clpid": "Tsai-Peter" }, { "family_name": "P\u00e1l", "given_name": "Margit", "clpid": "P\u00e1l-Margit" }, { "family_name": "Mar\u00f3y", "given_name": "P\u00e9ter", "clpid": "Mar\u00f3y-P\u00e9ter" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "De\u00e1k", "given_name": "P\u00e9ter", "clpid": "De\u00e1k-P\u00e9ter" }, { "family_name": "Bellen", "given_name": "Hugo J.", "clpid": "Bellen-H-J" } ], "abstract": "To identify novel genes and to isolate tagged mutations in known genes that are required for the development of the peripheral nervous system (PNS), we have screened a novel collection of 2460 strains carrying lethal or semilethal P element insertions on the third chromosome. Monoclonal antibody 22C10 was used as a marker to visualize the embryonic PNS. We identified 109 mutant strains that exhibited reproducible phenotypes in the PNS. Cytological and genetic analyses of these strains indicated that 87 mutations affect previously identified genes: tramtrack (n = 18 alleles), string (n = 15), cyclin A (n = 13), single-minded (n = 13), Delta (n = 9), neuralized (n = 4), pointed (n = 4), extra macrochaetae (n = 4), prospero (n = 3), tartan (n = 2), and pebble (n = 2). In addition, 13 mutations affect genes that we identified recently in a chemical mutagenesis screen designed to isolate similar mutants: hearty (n = 3), dorsotonals (n = 2), pavarotti (n = 2), sanpodo (n = 2), dalmatian (n = 1), missensed (n = 1), senseless (n = 1), and sticky ch1 (n = 1). The remaining nine mutations define seven novel complementation groups. The data presented here demonstrate that this collection of P elements will be useful for the identification and cloning of novel genes on the third chromosome, since >70% of mutations identified in the screen are caused by the insertion of a P element. A comparison between this screen and a chemical mutagenesis screen undertaken earlier highlights the complementarity of the two types of genetic screens.", "pmcid": "PMC1208342", "issn": "0016-6731", "publisher": "Genetics Society of America", "publication": "Genetics", "publication_date": "1997-12", "series_number": "4", "volume": "147", "issue": "4", "pages": "1723-1741" }, { "id": "authors:3zw3m-mq246", "collection": "authors", "collection_id": "3zw3m-mq246", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359784", "type": "article", "title": "The Drosophila Gene abnormal spindle Encodes a Novel Microtubule-associated Protein That Associates with the Polar Regions of the Mitotic Spindle", "author": [ { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "do Carmo Avides", "given_name": "Maria", "clpid": "do-Carmo-Avides-M" }, { "family_name": "Howard", "given_name": "Thomas", "clpid": "Howard-Thomas" }, { "family_name": "Gonzalez", "given_name": "Cayetano", "clpid": "Gonzalez-Cayetano" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "abnormal spindle, a gene required for normal spindle structure and function in Drosophila melanogaster, lies immediately adjacent the gene tolloid at 96A/B. It encodes a 220-kD polypeptide with a predicted pI of 10.8. The recessive mutant allele asp1 directs the synthesis of a COOH terminally truncated or internally deleted peptide of \u223c124 kD. Wild-type Asp protein copurifies with microtubules and is not released by salt concentrations known to dissociate most other microtubule-associated proteins. The bacterially expressed NH2-terminal 512-amino acid peptide, which has a number of potential phosphorylation sites for p34cdc2 and MAP kinases, strongly binds to microtubules. The central 579-amino acid segment of the molecule contains one short motif homologous to sequences in a number of actin bundling proteins and a second motif present at the calmodulin binding sites of several proteins. Immunofluorescence studies show that the wild-type Asp protein is localized to the polar regions of the spindle immediately surrounding the centrosome. These findings are discussed in relation to the known spindle abnormalities in asp mutants.", "doi": "10.1083/jcb.137.4.881", "pmcid": "PMC2139842", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "1997-05-19", "series_number": "4", "volume": "137", "issue": "4", "pages": "881-890" }, { "id": "authors:qr9vg-kqq57", "collection": "authors", "collection_id": "qr9vg-kqq57", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359875", "type": "article", "title": "Homologous regions of Fen1 and p21^(Cip1) compete for binding to the same site on PCNA: a potential mechanism to co-ordinate DNA replication and repair", "author": [ { "family_name": "Warbrick", "given_name": "Emma", "clpid": "Warbrick-Emma" }, { "family_name": "Lane", "given_name": "David P.", "clpid": "Lane-D-P" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Cox", "given_name": "Lynne S.", "clpid": "Cox-L-S" } ], "abstract": "Following genomic damage, the cessation of DNA replication is co-ordinated with onset of DNA repair; this co-ordination is essential to avoid mutation and genomic instability. To investigate these phenomena, we have analysed proteins that interact with PCNA, which is required for both DNA replication and repair. One such protein is p21^(Cip1), which inhibits DNA replication through its interaction with PCNA, while allowing repair to continue. We have identified an interaction between PCNA and the structure specific nuclease, Fen1, which is involved in DNA replication. Deletion analysis suggests that p21^(Cip1) and Fen1 bind to the same region of PCNA. Within Fen1 and its homologues a small region (10 amino acids) is sufficient for PCNA binding, which contains an 8 amino acid conserved PCNA-binding motif. This motif shares critical residues with the PCNA-binding region of p21^(Cip1). A PCNA binding peptide from p21^(Cip1) competes with Fen1 peptides for binding to PCNA, disrupts the Fen1-PCNA complex in replicating cell extracts, and concomitantly inhibits DNA synthesis. Competition between homologous regions of Fen1 and p21^(Cip1) for binding to the same site on PCNA may provide a mechanism to co-ordinate the functions of PCNA in DNA replication and repair.", "doi": "10.1038/sj.onc.1201072", "issn": "0950-9232", "publisher": "Nature Publishing Group", "publication": "Oncogene", "publication_date": "1997-05-15", "series_number": "19", "volume": "14", "issue": "19", "pages": "2313-2321" }, { "id": "authors:d7tdm-etg98", "collection": "authors", "collection_id": "d7tdm-etg98", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144643398", "type": "article", "title": "Mutation of a gene for a Drosophila kinesin-like protein, Klp38B, leads to failure of cytokinesis", "author": [ { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "T\u0151r\u0151k", "given_name": "Tibor", "clpid": "T\u0151r\u0151k-Tibor" }, { "family_name": "Tick", "given_name": "Gabriella", "clpid": "Tick-Gabriella" }, { "family_name": "Hoheisel", "given_name": "J\u00f6rg", "clpid": "Hoheisel-J" }, { "family_name": "Kiss", "given_name": "Istv\u00e1n", "clpid": "Kiss-Istv\u00e1n" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Mutations in a gene (Klp38B) encoding a novel kinesin-like protein in Drosophila melanogaster lead to the formation of polyploid cells in the larval central nervous system and in the follicle cells of adult egg chambers. Some homozygous mutants survive to adulthood and also exhibit morphological defects indicative of abnormal cell cycle progression, including rough eyes, missing bristles, and abnormal abdominal cuticles. In larval brains, there is no accumulation of mitotic cells and the frequency of anaphase figures is comparable to wild type, suggesting that nuclear division is not affected. Such brains contain polyploid cells with metaphase and anaphase chromosomes associated with bipolar spindles. Such spindles have a number of unseparated centrosomes at their poles reflecting the degree of polyploidy of the cell. Follicle cells frequently contain two nuclei of roughly equal size. Taken together, we conclude that these Klp38B mutations lead to a failure of cytokinesis resulting in polyploidy, and discuss whether or not this is a direct effect of the mutation.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1997-04", "series_number": "8", "volume": "110", "issue": "8", "pages": "945-954" }, { "id": "authors:2ge0h-hh337", "collection": "authors", "collection_id": "2ge0h-hh337", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-153617012", "type": "article", "title": "Polo kinase: the choreographer of the mitotic stage?", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "Tavares", "given_name": "\u00c1lvaro", "clpid": "Tavares-\u00c1" } ], "abstract": "The regulation of protein function through phosphorylation is fundamental in controlling cell cycle progression. To date, most attention has focused on the cyclin-dependent protein kinases (cdks) 1 (for review see reference 21). However, whereas the p34^(cdc)-cyclin B complex appears to regulate the mitotic \"state\" and in this way changes the overall organization of the cell, members of another conserved serine/threonine kinase family appears to be able to control the dynamics of cellular architecture. These are the polo-like kinases (plks) which orchestrate several mitotic events including the formation of the bipolar spindle, and at least in some organisms, the process of cytokinesis. It appears that in some of its roles the plk cooperates with p34^(cdc2) and indeed recent work (15) has suggested that one plk can help maintain the mitotic state by phosphorylating the cdc25 phosphatase that activates p34^(cdc2).", "doi": "10.1083/jcb.135.6.1681", "pmcid": "PMC2133943", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "1996-12-15", "series_number": "6", "volume": "135", "issue": "6", "pages": "1681-1684" }, { "id": "authors:k0q74-hxc35", "collection": "authors", "collection_id": "k0q74-hxc35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163116487", "type": "article", "title": "Chromatid Segregation at Anaphase Requires the barren Product, a Novel Chromosome-Associated Protein That Interacts with Topoisomerase II", "author": [ { "family_name": "Bhat", "given_name": "Manzoor A.", "clpid": "Bhat-Manzoor-A" }, { "family_name": "Philp", "given_name": "Alastair Valentine", "clpid": "Philp-A-V" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Bellen", "given_name": "Hugo J.", "clpid": "Bellen-H-J" } ], "abstract": "We have isolated a Drosophila gene, barren (barr), required for sister-chromatid segregation in mitosis. barr encodes a novel protein that is present in proliferating cells and has homologs in yeast and human. Mitotic defects in barr embryos become apparent during cycle 16, resulting in a loss of PNS and CNS neurons. Centromeres move apart at the metaphase\u2013anaphase transition and Cyclin B is degraded, but sister chromatids remain connected, resulting in chromatin bridging. This phenotype is similar to that described in TOP2 mutants in yeast. Barren protein localizes to chromatin throughout mitosis. Colocalization and biochemical experiments indicate that Barren associates with Topoisomerase II throughout mitosis and alters the activity of Topoisomerase II. We propose that this association is required for proper chromosomal segregation by facilitating the decatenation of chromatids at anaphase.", "doi": "10.1016/s0092-8674(00)81804-8", "issn": "0092-8674", "publisher": "Cell Press", "publication": "Cell", "publication_date": "1996-12-13", "series_number": "6", "volume": "87", "issue": "6", "pages": "1103-1114" }, { "id": "authors:t5jz4-s9260", "collection": "authors", "collection_id": "t5jz4-s9260", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-152641312", "type": "article", "title": "A maternal requirement for glutamine synthetase I for the mitotic cycles of syncytial Drosophila embryos", "author": [ { "family_name": "Frenz", "given_name": "Lisa M.", "clpid": "Frenz-L-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We describe the maternal effect phenotype of a hypomorphic mutation in the Drosophila gene for glutamine synthetase I (GSI). The extent of development of embryos derived from homozygous mutant females is variable, although most mutant embryos fail to survive past germband elongation and none develop into larvae. These embryos are characterised by an increase in the number of yolk-like nuclei following nuclear migration to the cortex. These nuclei appear to fall into the interior of the embryo from the cortex at blastoderm. As they do so, the majority continue to show association with PCNA in synchrony with nuclei at the cortex, suggesting some continuity of the synchrony of DNA replication. However, the occurrence of nuclei that have lost cell cycle synchrony with their neighbours is not uncommon. Immunostaining of mutant embryos revealed a range of mitotic defects, ultimately resulting in nuclear fusion events, division failure or other mitotic abnormalities. A high proportion of these mitotic figures show chromatin bridging at anaphase and telophase consistent with progression through mitosis in the presence of incompletely replicated DNA. GSI is responsible for the ATP-dependent amination of glutamate to produce glutamine, which is required in the formation of amino acids, purines and pyrimidines. We discuss how the loss of glutamine could depress both protein and DNA synthesis and lead to a variety of mitotic defects in this embryonic system that lacks certain checkpoint controls.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1996-11", "series_number": "11", "volume": "109", "issue": "11", "pages": "2649-2660" }, { "id": "authors:w73yh-e9212", "collection": "authors", "collection_id": "w73yh-e9212", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-133531673", "type": "article", "title": "The conserved mitotic kinase polo is regulated by phosphorylation and has preferred microtubule-associated substrates in Drosophila embryo extracts", "author": [ { "family_name": "Tavares", "given_name": "\u00c1lvaro A. M.", "clpid": "Tavares-\u00c1lvaro-A-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Sunkel", "given_name": "Claudio E.", "clpid": "Sunkel-C-E" } ], "abstract": "The Drosophila gene polo encodes a protein kinase required for progression through mitosis. Wild\u2010type polo protein migrates as a tight doublet of 67 kDa which is converted to a single band by phosphatase treatment, which also inactivates the kinase. We have determined putative polo substrates in a cell\u2010free system derived from mutant embryos. Exogenous polo protein kinase phosphorylates proteins of sizes 220 kDa, 85 kDa and 54 kDa, to a greater extent when added to extracts of polo(1)\u2010derived embryos compared with extracts of wild\u2010type embryos, which in both cases have been subject to mild heat treatment to inactivate endogenous kinases. Proteins of the same size are predominantly phosphorylated by the endogenous kinases present in wild\u2010type extracts, and are either not phosphorylated or are poorly phosphorylated in extracts of polo(1)\u2010derived embryos. We show that a specific monoclonal antibody to beta\u2010tubulin precipitates the phosphorylated 54 kDa protein together with an associated 85 kDa protein also phosphorylated by polo protein kinase. Moreover polo binds to an 85 kDa protein which is enriched in microtubule preparations. We discuss the extent to which these in vitro phosphorylation results reflect the effects of mutations in polo on microtubule behaviour during the mitotic cycle.", "doi": "10.1002/j.1460-2075.1996.tb00868.x", "pmcid": "PMC452225", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "1996-09", "series_number": "18", "volume": "15", "issue": "18", "pages": "4873-4883" }, { "id": "authors:8n382-q5x83", "collection": "authors", "collection_id": "8n382-q5x83", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123320058", "type": "article", "title": "The 190 kDa centrosome-associated protein of Drosophila melanogaster contains four zinc finger motifs and binds to specific sites on polytene chromosomes", "author": [ { "family_name": "Whitfield", "given_name": "W. G. F.", "clpid": "Whitfield-W-G-F" }, { "family_name": "Chaplin", "given_name": "M. A.", "clpid": "Chaplin-M-A" }, { "family_name": "Oegema", "given_name": "K.", "clpid": "Oegema-K" }, { "family_name": "Parry", "given_name": "H.", "clpid": "Parry-Huw" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Microinjection of a bacterially expressed, TRITC labelled fragment of the centrosome-associated protein CP190 of Drosophila melanogaster, into syncytial Drosophila embryos, shows it to associate with the centrosomes during mitosis, and to relocate to chromatin during interphase. Indirect immunofluorescence staining of salivary gland chromosomes of third instar Drosophila larvae, with antibodies specific to CP190, indicate that the protein is associated with a large number of loci on these interphase polytene chromosomes. The 190 kDa CP190 protein is encoded by a 4.1 kb transcript with a single, long open reading frame specifying a polypeptide of 1,096 amino acids, with a molecular mass of 120 kDa, and an isoelectric point of 4.5. The central region of the predicted amino acid sequence of the CP190 protein contains four CysX\u2082CysX\u2081\u2082HisX\u2084His zinc-finger motifs which are similar to those described for several well characterised DNA binding proteins. The data suggest that the function of CP190 involves cell cycle dependent associations with both the centrosome, and with specific chromosomal loci.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1995-11", "series_number": "11", "volume": "108", "issue": "11", "pages": "3377-3387" }, { "id": "authors:pbx5x-0fg91", "collection": "authors", "collection_id": "pbx5x-0fg91", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353435", "type": "article", "title": "The conserved Schizosaccharomyces pombe kinase plo1, required to form a bipolar spindle, the actin ring, and septum, can drive septum formation in G\u2081 and G\u2082 cells", "author": [ { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "Hagan", "given_name": "Iain M.", "clpid": "Hagan-I-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have identified a Schizosaccharomyces pombe gene with homology to the budding yeast gene CDC5, the Drosophila gene polo, and the mammalian family of genes encoding polo-like kinases. Disruption of this gene, plo1\u207a, indicates that it is essential. Loss of plo1\u207a function leads to a mitotic arrest in which condensed chromosomes are associated with a monopolar spindle or to the failure of septation following the completion of nuclear division. In the latter case, cells show a failure both in the formation of an F-actin ring and in the deposition of septal material, suggesting that plo1\u207a function is required high in the regulatory cascade that controls septation. The overexpression of plo1\u207a in wild-type cells also results in the formation of monopolar spindles but also induces the formation of multiple septa without nuclear division. Septation can also be induced in the absence of mitotic commitment and concomitant spindle formation by the overexpression of plo1\u207a in cdc25-22 or cdc2-33 cells arrested in G\u2082; in G\u2081 cells arrested at Start by the cdc10-V50 mutation, or in cells lacking the cyclin B homolog cdc13 that undergo repeated S phases in the absence of mitosis.", "doi": "10.1101/gad.9.9.1059", "issn": "0890-9369", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Genes and Development", "publication_date": "1995-05-01", "series_number": "9", "volume": "9", "issue": "9", "pages": "1059-1073" }, { "id": "authors:7qa6t-zn712", "collection": "authors", "collection_id": "7qa6t-zn712", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163116598", "type": "article", "title": "Mutations in aurora prevent centrosome separation leading to the formation of monopolar spindles", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Leibowitz", "given_name": "Mark H.", "clpid": "Leibowitz-M-H" }, { "family_name": "McLean", "given_name": "Doris A.", "clpid": "McLean-D-A" }, { "family_name": "Parry", "given_name": "Huw", "clpid": "Parry-Huw" } ], "abstract": "We show that female sterile mutations of aurora (aur) are allelic to mutations in the lethal complementation group ck\u00b9\u2070. This lies in a cytogenetic interval, 87A7-A9, that contains eight transcription units. A 250 by region upstream of both aur and a divergent transcription unit corresponds to the site of a specific chromatin structure (scs\u2032) previously proposed to be a barrier to insulate enhancers of the major hsp70 gene at 87A7. Syncytial embryos derived from aur mothers display closely paired centrosomes at inappropriate mitotic stages and develop interconnected spindles in which the poles are shared. Amorphic alleles result in pupal lethality and in mitotic arrest in which condensed chromosomes are arranged on circular monopolar spindles. The size of the single centrosomal body in these circular figures suggests that loss of function of the serine-threonine protein kinase encoded by aur leads to a failure of the centrosomes to separate and form a bipolar spindle.", "doi": "10.1016/0092-8674(95)90374-7", "issn": "0092-8674", "publisher": "Cell Press", "publication": "Cell", "publication_date": "1995-04-07", "series_number": "1", "volume": "81", "issue": "1", "pages": "95-105" }, { "id": "authors:b8twf-z5a31", "collection": "authors", "collection_id": "b8twf-z5a31", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626732", "type": "article", "title": "A small peptide inhibitor of DNA replication defines the site of interaction between the cyclin-dependent kinase inhibitor p21^(WAF1) and proliferating cell nuclear antigen", "author": [ { "family_name": "Warbrick", "given_name": "Emma", "clpid": "Warbrick-Emma" }, { "family_name": "Lane", "given_name": "David P.", "clpid": "Lane-D-P" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Cox", "given_name": "Lynne S.", "clpid": "Cox-L-S" } ], "abstract": "Background: p21^(WAF1) is a potent inhibitor of the cell-cycle regulatory cyclin-dependent kinases (Cdks). It acts on Cdks in the G1 and S phases of the cell cycle, and also binds to proliferating cell nuclear antigen (PCNA), blocking DNA replication in vitro. Transcription of p21^(WAF1) can be induced by the human tumour suppressor protein p53, suggesting that the action of p21^(WAF1) may be important in cancer prevention. We have investigated the interaction between p21^(WAF1) and PCNA using a genetic two-hybrid screen and with arrays of synthetic peptides derived from the p21^(WAF1) protein sequence. \n\nResults We have established that the carboxy-terminal region of p21^(WAF1) interacts with PCNA in a yeast two-hybrid screen. Interaction with p21^(WAF1) involves the central loop of PCNA, which connects the two domains of the PCNA monomer. The interaction was finely mapped using peptides derived from the entire sequence of the p21^(WAF1) protein, and the critical residues were found to be QTSMTDFY (amino acids 144\u2013151 of p21^(WAF1)). Remarkably, a 20-residue peptide containing this sequence inhibited replication of simian virus 40 (SV40) DNA in vitro and could capture PCNA from whole cell extracts, demonstrating that small molecules can retain the biological activity characteristic of the whole protein. Sequential alanine-scan mutations of the peptide demonstrated that its ability to block replication correlates with its affinity for binding PCNA. \n\nConclusion We have shown that PCNA and the cell-cycle regulator p21^(WAF1) interact in vivo, and that this interaction requires the central loop of PCNA and an eight amino-acid motif from the carboxyl terminus of p21^(WAF1). Peptides of p21^(WAF1) that interact with PCNA can inhibit DNA replication; such peptides or mimetics may thus prove useful in the treatment of hyper-proliferative diseases, including cancer.", "doi": "10.1016/s0960-9822(95)00058-3", "issn": "0960-9822", "publisher": "Cell Press", "publication": "Current Biology", "publication_date": "1995-03", "series_number": "3", "volume": "5", "issue": "3", "pages": "275-282" }, { "id": "authors:x65ps-g2116", "collection": "authors", "collection_id": "x65ps-g2116", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143629865", "type": "article", "title": "Expression of N-terminally truncated cyclin B in the Drosophila larval brain leads to mitotic delay at late anaphase", "author": [ { "family_name": "Rimmington", "given_name": "Georgina", "clpid": "Rimmington-Georgina" }, { "family_name": "Dalby", "given_name": "Brian", "clpid": "Dalby-Brian" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have introduced an N-terminally truncated form of cyclin B into the Drosophila germ-line downstream of the yeast upstream activator that responds to GAL4. When such lines of flies are crossed to lines in which GAL4 is expressed in imaginal discs and larval brain, the majority of the resulting progeny die at the late pupal stage of development. Very rarely (< 0.1% of progeny) adults emerge that have a mutant phenotype typical of flies with mutations in genes required for the cell cycle; they have rough eyes, deformed wings, abnormal bristles, and die within hours of emergence. The brains of third instar larval progeny show an abnormally high proportion of mitotic cells containing overcondensed chromatids that have undergone anaphase separation, together with cells that cannot be assigned to a particular mitotic stage. Immunostaining indicates that these anaphase cells contain moderate levels of cyclin B, suggesting that persistent p34^(cdc2) kinase activity can prevent progression from anaphase into telophase.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1994-10", "series_number": "10", "volume": "107", "issue": "10", "pages": "2729-2738" }, { "id": "authors:0ated-4yg18", "collection": "authors", "collection_id": "0ated-4yg18", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143628989", "type": "article", "title": "Drosophila mutants in the 55 kDa regulatory subunit of protein phosphatase 2A show strongly reduced ability to dephosphorylate substrates of p34^(cdc2)", "author": [ { "family_name": "Mayer-Jaekel", "given_name": "Regina E.", "clpid": "Mayer-Jaekel-R-E" }, { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "Ferrigno", "given_name": "Paul", "clpid": "Ferrigno-Paul" }, { "family_name": "Andjelkovic", "given_name": "Natasa", "clpid": "Andjelkovic-Natasa" }, { "family_name": "Shiomi", "given_name": "Kensuke", "clpid": "Shiomi-Kensuke" }, { "family_name": "Uemura", "given_name": "Tadashi", "clpid": "Uemura-Tadashi" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hemmings", "given_name": "Brian A.", "clpid": "Hemmings-B-A" } ], "abstract": "The 55 kDa regulatory subunit of Drosophila protein phosphatase 2A is located in the cytoplasm at all cell cycle stages, by the criterion of immunofluorescence. We are unable to detect significant change in protein phosphatase activity during the nuclear division cycle of syncytial embryos. However, cell cycle function of the enzyme is suggested by the mitotic defects exhibited by two Drosophila mutants, aar\u00b9 and twins^P, defective in the gene encoding the 55 kDa subunit. The reduced levels of the 55 kDa subunit correlate with the loss of protein phosphatase 2A-like, okadaic acid-sensitive phosphatase activity of brain extracts against caldesmon and histone H1 phosphorylated by p34^(cdc2)/cyclin B kinase, but not against phosphorylase a. Thus the mitotic defects of aar\u00b9 and twins^P are likely to result from the lack of dephosphorylation of specific substrates by protein phosphatase 2A.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1994-09", "series_number": "9", "volume": "107", "issue": "9", "pages": "2609-2616" }, { "id": "authors:kcxg6-w4y72", "collection": "authors", "collection_id": "kcxg6-w4y72", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143628103", "type": "article", "title": "The cdc25 homologue twine is required for only some aspects of the entry into meiosis in Drosophila", "author": [ { "family_name": "White-Cooper", "given_name": "Helen", "orcid": "0000-0002-3373-8023", "clpid": "White-Cooper-H" }, { "family_name": "Alphey", "given_name": "Luke", "clpid": "Alphey-L-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The twine^(HB5) mutation prevents spindle formation during the entry into meiosis in Drosophila males, but chromosome condensation and nuclear envelope breakdown both still occur. This suggests the possibility that this particular cdc25 homologue is required to activate a p34^(cdc2) kinase required for only some of the events of this G\u2082-M transition. In contrast, meiotic spindles do form in twine^(HB5) females, although these appear abnormal. However, the female meiotic divisions do not arrest at metaphase I as in wild type, but continue repeatedly, leading to gross non-disjunction. Small chromatin masses, corresponding in size to the fourth chromosomes, often segregate properly to the spindle poles. These can persist into the embryos derived from twine^(HB5) females, where they appear to participate in mitotic divisions on thin spindles. In addition, these embryos contain a small number of large chromatin masses that are not associated with spindles.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1993-12", "series_number": "4", "volume": "106", "issue": "4", "pages": "1035-1044" }, { "id": "authors:x0pq6-8jy20", "collection": "authors", "collection_id": "x0pq6-8jy20", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-145945750", "type": "article", "title": "Mutations in the Drosophila melanogaster gene three rows permit aspects of mitosis to continue in the absence of chromatid segregation", "author": [ { "family_name": "Philp", "given_name": "Alistair Valentine", "clpid": "Philp-A-V" }, { "family_name": "Axton", "given_name": "J. Myles", "clpid": "Axton-J-M" }, { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have cloned the three rows (thr) gene, by a combination of chromosome microdissection and P element tagging. We describe phenotypes of embryos homozygous for mutations at the thr locus. Maternal mRNA and protein appear to be sufficient to allow 14 rounds of mitosis in embryos homozygous for thr mutations. However, a small percentage of cells in syncytial blastoderm stage thr embryos sink into the interior of the embryo as if they have failed to divide properly. Following cellularisation all cells complete mitosis 14 normally. All cells become delayed at mitosis 15 with their chromosomes remaining aligned on the spindle in a metaphase-like configuration, even though both cyclins A and B have both been degraded. As cyclin B degradation occurs at the metaphase-anaphase transition, subsequent to the microtubule integrity checkpoint, the delay induced by mutations at the thr locus defines a later point in mitotic progression. Chromosomes in the cells of thr embryos do not undertake anaphase separation, but remain at the metaphase plate. Subsequently they decondense. A subset of nuclei go on to replicate their DNA but there is no further mitotic division.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1993-09", "series_number": "1", "volume": "106", "issue": "1", "pages": "87-98" }, { "id": "authors:as4vs-ms282", "collection": "authors", "collection_id": "as4vs-ms282", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200812-153138786", "type": "article", "title": "Heat shock results in cell cycle delay and synchronisation of mitotic domains in cellularised Drosophila melanogaster embryos", "author": [ { "family_name": "Maldonado-Codina", "given_name": "Gabriela", "clpid": "Maldonado-Codina-G" }, { "family_name": "Llamazares", "given_name": "Salud", "clpid": "Llamazares-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Cells of Drosophila embryos that are subjected to a 37 degrees C temperature shock whilst undergoing the S-phase of cell cycle 14 arrest with their microtubules in an interphase-like state, and with nuclei showing unusual chromatin condensation. They do not recover from this state within a 30 minute period even though extensive gastrulation movements can occur. Cells of embryos heat shocked in G2-phase are delayed in interphase with high levels of cyclins A and B. Within ten minutes recovery from heat shock, cells enter mitosis throughout the embryo. The degradation of the mitotic cyclins A and B in these synchronised mitotic domains does not follow the normal timing, but is delayed. These findings point to a need for caution when interpreting experiments that use the heat shock promoter to study the expression of cell cycle control genes in Drosophila.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1993-07", "series_number": "3", "volume": "105", "issue": "3", "pages": "711-20" }, { "id": "authors:jc03p-waw05", "collection": "authors", "collection_id": "jc03p-waw05", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-133531861", "type": "article", "title": "Discrete sequence elements control posterior pole accumulation and translational repression of maternal cyclin B RNA in Drosophila", "author": [ { "family_name": "Dalby", "given_name": "Brian", "clpid": "Dalby-Brian" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The concentration of cyclin B transcripts at the posterior pole of the Drosophila oocyte occurs at a late stage of oogenesis and is dependent on the sequence in the 3\u2032 untranslated part of the RNA. These transcripts become incorporated into the pole cells of the developing embryo and persist through a subsequent period of embryogenesis in which these cells are not dividing. We show that RNA injected into the posterior cytoplasm of syncytial embryos accumulates in the pole cells if it contains sequences present in the 3\u2032 untranslated region of maternal cyclin B transcripts. The injected RNA is not translated until a point prior to the resumption of mitosis by these cells, once they have become incorporated into the gonads. Zygotic transcription directed from the cyclin B promoter does not begin in the pole cells until the first instar larva has hatched. Deletion of a small sequence element from the 3\u2032 untranslated region of an epitope tagged cyclin B RNA does not affect its posterior accumulation but results in its premature translation.", "doi": "10.1002/j.1460-2075.1993.tb05763.x", "pmcid": "PMC413325", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "1993-03", "series_number": "3", "volume": "12", "issue": "3", "pages": "1219-1227" }, { "id": "authors:9tpdh-mf747", "collection": "authors", "collection_id": "9tpdh-mf747", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144644247", "type": "article", "title": "Abnormal anaphase resolution (aar): a locus required for progression through mitosis in Drosophila", "author": [ { "family_name": "Gomes", "given_name": "R.", "clpid": "Gomes-R" }, { "family_name": "Karess", "given_name": "R. E.", "clpid": "Karess-R-E" }, { "family_name": "Ohkura", "given_name": "H.", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Sunkel", "given_name": "C. E.", "clpid": "Sunkel-C-E" } ], "abstract": "We describe a new mitotic locus of Drosophila melanogaster required for the progression through mitosis in the syncytial embryo and in late larval development. The locus aar (abnormal anaphase resolution) maps to the cytological interval 85E7-F16 and was identified by two alleles. The aar\u00b9 allele causes pupal lethality. Larval neuroblasts show an elevated mitotic index with high chromosome condensation and stretched and lagging chromatids during anaphase. aar\u00b2 produces fully viable but sterile females. aar\u00b9/aar\u00b2 females lay eggs that develop mitotic figures with similar abnormalities to those observed in neuroblasts. Indirect immunofluorescence of these embryos indicates that the centrosome cycle appears normal, although some abnormal spindle microtubules can be seen during mitosis.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1993-02", "series_number": "2", "volume": "104", "issue": "2", "pages": "583-593" }, { "id": "authors:kxmks-r8t68", "collection": "authors", "collection_id": "kxmks-r8t68", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143627215", "type": "article", "title": "3' non-translated sequences in Drosophila cyclin B transcripts direct posterior pole accumulation late in oogenesis and peri-nuclear association in syncytial embryos", "author": [ { "family_name": "Dalby", "given_name": "Brian", "clpid": "Dalby-Brian" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have characterised forms of the Drosophila cyclin B transcript that differ as a result of a splicing event which removes a nucleotide segment from the 3' untranslated region. In oogenesis, both cyclin A RNA and a shorter form of the cyclin B transcript are seen in the cells of the germarium that are undergoing mitosis. The shorter cyclin B transcript alone is then detectable in the presumptive oocyte until stages 7-8 of oogenesis. Both cyclin A RNA and a longer form of the cyclin B RNA are then synthesised in the nurse cells during stages 9-11, to be deposited in the oocyte during stages 11-12. These transcripts become evenly distributed throughout the oocyte cytoplasm but, in addition, those of cyclin B become concentrated at the posterior pole. Examination of the distributions of RNAs transcribed from chimeric cyclin genes indicates that sequences in the 3' untranslated region of the larger cyclin B RNA are required both for it to become concentrated at the posterior pole and to direct those transcripts in the body of the syncytial embryo to their peri-nuclear localisation. These sequences are disrupted by the splicing event which generates smaller cyclin B transcripts.", "issn": "0950-1991", "publisher": "Company of Biologists", "publication": "Development", "publication_date": "1992-08", "series_number": "4", "volume": "115", "issue": "4", "pages": "989-997" }, { "id": "authors:2pqwd-akp50", "collection": "authors", "collection_id": "2pqwd-akp50", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123359997", "type": "article", "title": "Dodeca satellite: a conserved G+C-rich satellite from the centromeric heterochromatin of Drosophila melanogaster", "author": [ { "family_name": "Abad", "given_name": "Jos\u00e9 P.", "clpid": "Abad-Jos\u00e9-P" }, { "family_name": "Carmena", "given_name": "Mar", "orcid": "0000-0002-2352-1066", "clpid": "Carmena-M" }, { "family_name": "Baars", "given_name": "Sigrid", "clpid": "Baars-Sigrid" }, { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Lude\u00f1a", "given_name": "Paloma", "clpid": "Lude\u00f1a-Paloma" }, { "family_name": "Sentis", "given_name": "Carlos", "clpid": "Sentis-Carlos" }, { "family_name": "Tyler-Smith", "given_name": "Chris", "clpid": "Tyler-Smith-C" }, { "family_name": "Villasante", "given_name": "Alfredo", "clpid": "Villasante-Alfredo" } ], "abstract": "To identify sequences from the centromeric region, we have constructed a Drosophila melanogaster yeast artificial chromosome (YAC) library and screened it with purified DNA from the minichromosome Dp(1;f)1187 derived from the X chromosome. We describe the structure of one clone isolated in this way. This YAC is structurally unstable and contains tandemly repeated G+C-rich 11-mer and 12-mer units, which we call dodeca satellite. Most of this satellite is located near the centromere of an autosome. Cross-hybridizing sequences are found in the genomes of organisms as distant as Arabidopsis thaliana and Homo sapiens.", "doi": "10.1073/pnas.89.10.4663", "pmcid": "PMC49143", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "1992-05-15", "series_number": "10", "volume": "89", "issue": "10", "pages": "4663-4667" }, { "id": "authors:c1nrb-pgt64", "collection": "authors", "collection_id": "c1nrb-pgt64", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351589", "type": "article", "title": "Molecular cloning and developmental expression of the catalytic and 65-kDa regulatory subunits of protein phosphatase 2A in Drosophila", "author": [ { "family_name": "Mayer-Jaekel", "given_name": "Regina E.", "clpid": "Mayer-Jaekel-R-E" }, { "family_name": "Baumgartner", "given_name": "Stefan", "clpid": "Baumgartner-Stefan" }, { "family_name": "Bilbe", "given_name": "Graeme", "clpid": "Bilbe-G" }, { "family_name": "Ohkura", "given_name": "Hiroyuki", "clpid": "Ohkura-Hiroyuki" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hemmings", "given_name": "Brian A.", "clpid": "Hemmings-B-A" } ], "abstract": "cDNA clones encoding the catalytic subunit and the 65-kDa regulatory subunit of protein phosphatase 2A (PR65) from Drosophila melanogaster have been isolated by homology screening with the corresponding human cDNAs. The Drosophila clones were used to analyze the spatial and temporal expression of the transcripts encoding these two proteins. The Drosophila PR65 cDNA clones contained an open reading frame of 1773 nucleotides encoding a protein of 65.5 kDa. The predicted amino acid sequence showed 75 and 71% identity to the human PR65 alpha and beta isoforms, respectively. As previously reported for the mammalian PR65 isoforms, Drosophila PR65 is composed of 15 imperfect repeating units of approximately 39 amino acids. The residues contributing to this repeat structure show also the highest sequence conservation between species, indicating a functional importance for these repeats. The gene encoding Drosophila PR65 was located at 29B1,2 on the second chromosome. A major transcript of 2.8 kilobase (kb) encoding the PR65 subunit and two transcripts of 1.6 and 2.5 kb encoding the catalytic subunit could be detected throughout Drosophila development. All of these mRNAs were most abundant during early embryogenesis and were expressed at lower levels in larvae and adult flies. In situ hybridization of different developmental stages showed a colocalization of the PR65 and catalytic subunit transcripts. The mRNA expression is high in the nurse cells and oocytes, consistent with a high equally distributed expression in early embryos. In later embryonal development, the expression remains high in the nervous system and the gonads but the overall transcript levels decrease. In third instar larvae, high levels of mRNA could be observed in brain, imaginal discs, and in salivary glands. These results indicate that protein phosphatase 2A transcript levels change during development in a tissue and in a time-specific manner.", "doi": "10.1091/mbc.3.3.287", "pmcid": "PMC275530", "issn": "1059-1524", "publisher": "American Society for Cell Biology", "publication": "Molecular Biology of the Cell", "publication_date": "1992-03", "series_number": "3", "volume": "3", "issue": "3", "pages": "287-298" }, { "id": "authors:78p9x-evw09", "collection": "authors", "collection_id": "78p9x-evw09", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144714451", "type": "article", "title": "Cyclins A and B associate with chromatin and the polar regions of spindles, respectively, and do not undergo complete degradation at anaphase in syncytial Drosophila embryos", "author": [ { "family_name": "Maldonado-Codina", "given_name": "Gabriela", "clpid": "Maldonado-Codina-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Maternally contributed cyclin A and B proteins are initially distributed uniformly throughout the syncytial Drosophila embryo. As dividing nuclei migrate to the cortex of the embryo, the A and B cyclins become concentrated in surface layers extending to depths of approximately 30-40 microns and 5-10 microns, respectively. The initiation of nuclear envelope breakdown, spindle formation, and the initial congression of the centromeric regions of the chromosomes onto the metaphase plate all take place within the surface layer occupied by cyclin B on the apical side of the blastoderm nuclei. Cyclin B is seen mainly, but not exclusively, in the vicinity of microtubules throughout the mitotic cycle. It is most conspicuous around the centrosomes. Cyclin A is present at its highest concentrations throughout the cytoplasm during the interphase periods of the blastoderm cycles, although weak punctate staining can also be detected in the nucleus. It associates with the condensing chromosomes during prophase, segregates into daughter nuclei in association with chromosomes during anaphase, to redistribute into the cytoplasm after telophase. In contrast to the cycles following cellularization, neither cyclin is completely degraded upon the metaphase-anaphase transition.", "doi": "10.1083/jcb.116.4.967", "pmcid": "PMC2289331", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "1992-02-15", "series_number": "4", "volume": "116", "issue": "4", "pages": "967-976" }, { "id": "authors:v8yw5-sgn23", "collection": "authors", "collection_id": "v8yw5-sgn23", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123400111", "type": "article", "title": "Low-resolution genome map of the malaria mosquito Anopheles gambiae", "author": [ { "family_name": "Zheng", "given_name": "Liangbiao", "clpid": "Zheng-Liangbiao" }, { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Fortini", "given_name": "Daniela", "clpid": "Fortini-Daniela" }, { "family_name": "della Torre", "given_name": "Alessandra", "clpid": "della-Torre-Alessandra" }, { "family_name": "Coluzzi", "given_name": "Mario", "clpid": "Coluzzi-Mario" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Kafatos", "given_name": "Fotis C.", "clpid": "Kafatos-F-C" } ], "abstract": "We have microdissected divisions of the Anopheles gambiae polytene chromosomes, digested the DNAs with a restriction enzyme, and PCR-amplified the DNA fragments to generate a set of pooled probes, each corresponding to approximately 2% of the mosquito genome. These divisional probes were shown to have high complexity. Except for those derived from near the centromeres, they hybridize specifically with their chromosomal sites of origin. Thus, they can be used to map cloned DNAs by a dot blot procedure, which is much more convenient than in situ hybridization to polytene chromosomes. We discuss additional potential uses of these probes, such as easier isolation of molecular markers and genes, including those that cross-hybridize with clones available from other insects. It is expected that the probes will substantially accelerate molecular genetic analysis of this most important malaria vector.", "doi": "10.1073/pnas.88.24.11187", "pmcid": "PMC53099", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "1991-12-15", "series_number": "24", "volume": "88", "issue": "24", "pages": "11187-11191" }, { "id": "authors:8r40q-kpa46", "collection": "authors", "collection_id": "8r40q-kpa46", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143650434", "type": "article", "title": "polo encodes a protein kinase homolog required for mitosis in Drosophila", "author": [ { "family_name": "Llamazares", "given_name": "S.", "clpid": "Llamazares-S" }, { "family_name": "Moreira", "given_name": "A.", "clpid": "Moreira-A" }, { "family_name": "Tavares", "given_name": "A.", "clpid": "Tavares-A" }, { "family_name": "Girdham", "given_name": "C.", "clpid": "Girdham-C" }, { "family_name": "Spruce", "given_name": "B. A.", "clpid": "Spruce-B-A" }, { "family_name": "Gonzalez", "given_name": "C.", "clpid": "Gonzalez-C" }, { "family_name": "Karess", "given_name": "R. E.", "clpid": "Karess-R-E" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Sunkel", "given_name": "C. E.", "clpid": "Sunkel-C-E" } ], "abstract": "We show that mutation in polo leads to a variety of abnormal mitoses in Drosophila larval neuroblasts. These include otherwise normal looking mitotic spindles upon which chromosomes appear overcondensed; normal bipolar spindles with polyploid complements of chromosomes; bipolar spindles in which one pole can be unusually broad; and monopolar spindles. We have cloned the polo gene from a mutant allele carrying a P-element transposon and sequenced cDNAs corresponding to transcripts of the wild-type locus. The sequence shows that polo encodes a 577-amino-acid protein with an amino-terminal domain homologous to a serine-threonine protein kinase. polo transcripts are abundant in tissues and developmental stages in which there is extensive mitotic activity. The transcripts show no obvious spatial pattern of distribution in relation to the mitotic domains of cellularized embryos but are specifically concentrated in dividing cells in larval discs and brains. In the cell cycles of both syncytial and cellularized embryos, the polo kinase undergoes cell cycle-dependent changes in its distribution: It is predominantly cytoplasmic during interphase; it becomes associated with condensed chromosomes toward the end of prophase; and it remains associated with chromosomes until telophase, whereupon it becomes cytoplasmic.", "doi": "10.1101/gad.5.12a.2153", "issn": "0890-9369", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Genes and Development", "publication_date": "1991-12", "series_number": "12a", "volume": "5", "issue": "12a", "pages": "2153-2165" }, { "id": "authors:t23xj-95m04", "collection": "authors", "collection_id": "t23xj-95m04", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170353522", "type": "article", "title": "Chromosome tangling and breakage at anaphase result from mutations in lodestar, a Drosophila gene encoding a putative nucleoside triphosphate-binding protein", "author": [ { "family_name": "Girdham", "given_name": "Charles H.", "clpid": "Girdham-C-H" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We describe a Drosophila maternal-effect gene, lodestar, mutations in which cause chromatin bridges at anaphase. lodestar maps to cytological position 84D13-14, and we identified the lodestar gene in germ-line transformation experiments by the ability of a genomic fragment to restore fertility to females homozygous for lodestar mutations. lodestar encodes a potential nucleoside triphosphate binding protein, which is a novel member of the D-E-A-H box family of proteins. Antibodies raised against the lodestar gene product detect a protein that undergoes cell cycle-dependent changes in distribution in the embryo. The protein is cytoplasmic at interphase, and rapidly enters the nucleus early in prophase. It is restricted to the region enclosed by the spindle envelope during metaphase and anaphase; but by telophase, the lodestar protein is contained entirely within the reforming nucleus.", "doi": "10.1101/gad.5.10.1786", "issn": "0890-9369", "publisher": "Cold Spring Harbor Laboratory Press", "publication": "Genes and Development", "publication_date": "1991-10", "series_number": "10", "volume": "5", "issue": "10", "pages": "1786-1799" }, { "id": "authors:8st33-1n047", "collection": "authors", "collection_id": "8st33-1n047", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-133531975", "type": "article", "title": "The major serum protein of Drosophila larvae, larval serum protein 1, is dispensable", "author": [ { "family_name": "Roberts", "given_name": "David B.", "clpid": "Roberts-D-B" }, { "family_name": "Jowett", "given_name": "Trevor", "clpid": "Jowett-Trevor" }, { "family_name": "Hughes", "given_name": "Jane", "clpid": "Hughes-Jane" }, { "family_name": "Smith", "given_name": "Deborah F.", "clpid": "Smith-D-F" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Null alleles of all three genes (\u03b1, \u03b2 and \u03b3) coding for the major serum protein of Drosophila larvae, larval serum protein 1, have been characterized at the protein level and by analysis of their RNA and DNA. Each allele completely lacks one polypeptide chain. \u03b2\u00b0 shows an unaltered gene but reduced levels of RNA, \u03b1\u00b0 shows restriction\u2010fragment\u2010length polymorphism and shows low levels of transcript, while \u03b3\u00b0 is a deletion. The three null alleles have been combined to give a strain without the gene for larval serum protein 1 which survives", "doi": "10.1111/j.1432-1033.1991.tb15695.x", "issn": "0014-2956", "publisher": "Wiley", "publication": "European Journal of Biochemistry", "publication_date": "1991-01", "series_number": "1", "volume": "195", "issue": "1", "pages": "195-201" }, { "id": "authors:ghtfw-9r556", "collection": "authors", "collection_id": "ghtfw-9r556", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143626240", "type": "article", "title": "Two distinct mechanisms localise cyclin B transcripts in syncytial Drosophila embryos", "author": [ { "family_name": "Raff", "given_name": "Jordan W.", "orcid": "0000-0002-4689-1297", "clpid": "Raff-J-W" }, { "family_name": "Whitfield", "given_name": "William G. F.", "clpid": "Whitfield-W-G-F" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We demonstrate that two independent mechanisms act on maternally derived cyclin B transcripts to concentrate the transcripts at the posterior pole of the Drosophila oocyte and at the cortex of the syncytial embryo. The cortical accumulation occurs because the cyclin B transcript is concentrated around nuclei and comigrates with them to the cortex. The perinuclear localisation of the transcript is blocked by inhibitors of microtubule polymerisation and the transcript colocalises with microtubular structures during the cell cycle, suggesting that the transcript is associated either directly or indirectly with microtubules. Neither microtubules nor actin filaments are required to maintain the posterior concentration of cyclin B transcripts. Instead, this seems to depend on the association of the transcripts with a component of the posterior cytoplasm. The distribution pattern of the transcript at the posterior pole throughout embryogenesis and in a variety of mutant embryos suggests that this component is associated with polar granules.", "issn": "0950-1991", "publisher": "Company of Biologists", "publication": "Development", "publication_date": "1990-12", "series_number": "4", "volume": "110", "issue": "4", "pages": "1249-1261" }, { "id": "authors:8x032-m0a95", "collection": "authors", "collection_id": "8x032-m0a95", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351011", "type": "article", "title": "Towards a physical map of the Drosophila melanogaster genome: mapping of cosmid clones within defined genomic divisions", "author": [ { "family_name": "Sid\u00e9n-Kiamos", "given_name": "I.", "clpid": "Sid\u00e9n-Kiamos-I" }, { "family_name": "Saunders", "given_name": "R. D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Spanos", "given_name": "L.", "clpid": "Spanos-L" }, { "family_name": "Majerus", "given_name": "T.", "clpid": "Majerus-T" }, { "family_name": "Treanear", "given_name": "J.", "clpid": "Treanear-J" }, { "family_name": "Savakis", "given_name": "C.", "clpid": "Savakis-C" }, { "family_name": "Louis", "given_name": "C.", "clpid": "Louis-C" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Ashburner", "given_name": "M.", "clpid": "Ashburner-M" }, { "family_name": "Kafatos", "given_name": "F. C.", "clpid": "Kafatos-F-C" } ], "abstract": "A physical map of the D. melanogaster genome is being constructed, in the form of overlapping cosmid clones that are assigned to specific poiytene chromosome sites. A master library of Ca . 20,000 cosmids is screened with probes that correspond to numbered chromosomal divisions (ca. 1% of the genome); these probes are prepared by microdissection and PCRamplification of individual chromosomes. The 120 to 250 cosmids selected by each probe are fingerprinted by Hinfl digestion and gel electrophoresis, and overlaps are detected by computer analysis of the fingerprints, permitting us to assemble sets of contiguous clones (contigs). Selected cosmids, both from contlgs and unattached, are then localized by in situ hybridization to polytene chromosomes. Crosshybrldlzation analysIs using end probes links some contigs, and hybridization to previously cloned genes relates the physical to the genetic map. This approach has been used to construct a physical map of the 3.8 megabase DNA in the three distal divisions of the \u00d7 chromosome. The map is represented by 181 canonical cosmids, of which 108 clones in contigs and 32 unattached clones have been mapped Individually by in situ hybridization to chromosomes. Our current database of in situ hybridization results also includes the beginning of a physical map for the rest of the genome: 162 cosmids have been assigned by In situ hybridization to 129 chromosomal subdivisions elsewhere in the genome, representing 5 to 6 megabases of additional mapped DNA.", "doi": "10.1093/nar/18.21.6261", "pmcid": "PMC332490", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1990-11-21", "series_number": "21", "volume": "18", "issue": "21", "pages": "6261-6270" }, { "id": "authors:tb3vf-yc405", "collection": "authors", "collection_id": "tb3vf-yc405", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-133532081", "type": "article", "title": "Complementation of fission yeast cdc2^(ts) and cdc25^(ts) mutants identifies two cell cycle genes from Drosophila: a cdc2 homologue and string", "author": [ { "family_name": "Jimenez", "given_name": "Juan", "clpid": "Jimenez-Juan" }, { "family_name": "Alphey", "given_name": "Luke", "clpid": "Alphey-L-S" }, { "family_name": "Nurse", "given_name": "Paul", "clpid": "Nurse-Paul" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have exploited the universality of the molecular mechanisms that control entry into mitosis to clone the Drosophila melanogaster homologues of fission yeast Schizosaccharomyces pombe cell division control (cdc) genes by the complementation of temperature sensitive mutations. The Drosophila genes were expressed in S.pombe as cDNAs from the SP6 promoter. Successful recovery of complementing plasmids required that we first 'adapt' pooled plasmids from a Drosophila embryonic cDNA library for propagation in fission yeast by introducing an ars1\u2010LEU2 DNA fragment into the vector. This library was introduced into S.pombe cdc2 and cdc25 mutants, and plasmids isolated carrying cDNAs that complement these mutations. The gene that encodes the Drosophila cdc2 homologue maps to a single locus in the Drosophila genome at 31E on chromosome 2. It is expressed maternally to provide mRNA in syncytial embryos, and appears to be zygotically expressed in mitotically active regions of the cellularized embryo. We have isolated two different cDNAs that complement cdc25\u201022. One corresponds to a transcript of string, previously described as the Drosophila homologue of cdc25, and the other to a gene that has not been previously characterized.", "doi": "10.1002/j.1460-2075.1990.tb07567.x", "pmcid": "PMC552107", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "1990-11", "series_number": "11", "volume": "9", "issue": "11", "pages": "3565-3571" }, { "id": "authors:wbhzq-5dq47", "collection": "authors", "collection_id": "wbhzq-5dq47", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-133532215", "type": "article", "title": "The A- and B-type cyclins of Drosophila are accumulated and destroyed in temporally distinct events that define separable phases of the G2-M transition", "author": [ { "family_name": "Whitfield", "given_name": "William G. F.", "clpid": "Whitfield-W-G-F" }, { "family_name": "Gonzalez", "given_name": "Cayetano", "clpid": "Gonzalez-Cayetano" }, { "family_name": "Maldonado-Codina", "given_name": "Gabriela", "clpid": "Maldonado-Codina-G" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We show that the sequence of Drosophila cyclin B has greater identity with B\u2010type cyclins from other animal phyla than with Drosophila cyclin A, suggesting that the two cyclins have distinct roles that have been maintained in evolution. Cyclin A is not detectable in unfertilized eggs and is present at low levels prior to cellularization of the syncytial embryo. In contrast, the levels of cyclin B remain uniformly high throughout these developmental stages. In cells within cellularized embryos and the larval brain, cyclin A accumulates to peak levels in prophase and is degraded throughout the period in which chromosomes are becoming aligned on the metaphase plate. The degradation of cyclin B, on the other hand, does not occur until the metaphase\u2010anaphase transition. In cells arrested at c\u2010metaphase by treating with microtubule destabilizing drugs to prevent spindle formation, cyclin A has been degraded in the arrested cells, whereas cyclin B is maintained at high levels. These observations suggest that cyclin A has a role in the G2\u2010M transition that is independent of spindle formation, and that entry into anaphase is a key requirement for the degradation of cyclin B.", "doi": "10.1002/j.1460-2075.1990.tb07437.x", "pmcid": "PMC552287", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "1990-08", "series_number": "8", "volume": "9", "issue": "8", "pages": "2563-2572" }, { "id": "authors:3cft4-fjt43", "collection": "authors", "collection_id": "3cft4-fjt43", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144645081", "type": "article", "title": "Mutations at the asp locus of Drosophila lead to multiple free centrosomes in syncytial embryos, but restrict centrosome duplication in larval neuroblasts", "author": [ { "family_name": "Gonzalez", "given_name": "C.", "clpid": "Gonzalez-C" }, { "family_name": "Saunders", "given_name": "R. D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Casal", "given_name": "J.", "clpid": "Casal-J" }, { "family_name": "Molina", "given_name": "I.", "clpid": "Molina-I" }, { "family_name": "Carmena", "given_name": "M.", "clpid": "Carmena-M" }, { "family_name": "Ripoll", "given_name": "P.", "clpid": "Ripoll-P" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Mutations at abnormal spindle result in abnormally long and wavy microtubules in the meiotic spindles of males. Some of these spindles have a single pole and take the form of unopposed hemi-spindles. Unfertilised eggs produced by homozygous asp females may have either no nuclei, or a small number of large nuclei, consistent with there also being an effect upon female meiosis. Such eggs also display free centrosomes and independent arrays of microtubules. Embryos that have this phenotype are also present among the progeny of fertilised homozygous asp females, together with embryos that undergo varying degrees of aberrant morphogenesis, developing a variety of abnormal cuticle patterns. This latter category shows asynchronous mitoses prior to cellularisation, and has abnormal arrays of spindle microtubules. Such embryos can develop large areas that are either devoid of or have a reduced number of nuclei, in which there are centrosomes that have dissociated from the mitotic spindles. Neuroblasts in the brains of homozygous asp larvae display a high mitotic index, and have condensed chromosomes aligned as if blocked at metaphase. Immunostaining reveals that many cells contain a single centrosome connected to the metaphase chromosomes by microtubules in a hemi-spindle-like structure.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1990-08", "series_number": "4", "volume": "96", "issue": "4", "pages": "605-616" }, { "id": "authors:wx0fv-n0690", "collection": "authors", "collection_id": "wx0fv-n0690", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-145241437", "type": "article", "title": "A neuropeptide precursor in cerebellum: proenkephalin exists in subpopulations of both neurons and astrocytes", "author": [ { "family_name": "Spruce", "given_name": "Barbara A.", "clpid": "Spruce-B-A" }, { "family_name": "Curtis", "given_name": "Rory", "clpid": "Curtis-Rory" }, { "family_name": "Wilkin", "given_name": "Graham P.", "clpid": "Wilkin-G-P" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The adult rat cerebellum has minimal enkephalin immunoreactivity and is devoid of opiate\u2010binding activity. Using novel monoclonal antibodies to the mammalian enkephalin precursor, we describe the immunofluorescent detection of proenkephalin, in the absence of mature enkephalin peptides, in subpopulations of rat cerebellar neurons and astrocytes. In cryostat sections, neurons that express proenkephalin include Golgi cells, macroneurons within deep cerebellar nuclei and a subpopulation of Purkinje cells. Proenkephalin messenger RNA and protein are present in subpopulations of both grey and white matter astrocytes, but not Bergmann glia. In dissociated glial culture, proenkephalin is expressed in process\u2010bearing astrocytes, apparently in association with a subset of intermediate filaments. Proenkephalin within astrocytes is not seen until the second postnatal week and increases through to adulthood. Neuropeptide gene expression adds to the growing range of neuronal\u2010type properties glial cells can display.", "doi": "10.1002/j.1460-2075.1990.tb08303.x", "pmcid": "PMC551883", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "1990-06", "series_number": "6", "volume": "9", "issue": "6", "pages": "1787-1795" }, { "id": "authors:4611y-xgh03", "collection": "authors", "collection_id": "4611y-xgh03", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143650328", "type": "article", "title": "rough deal: a gene required for proper mitotic segregation in Drosophila", "author": [ { "family_name": "Karess", "given_name": "Roger E.", "clpid": "Karess-R-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We describe a genetic locus rough deal (rod) in Drosophila melanogaster, identified by mutations that interfere with the faithful transmission of chromosomes to daughter cells during mitosis. Five mutant alleles were isolated, each associated with a similar set of mitotic abnormalities in the dividing neuroblasts of homozygous mutant larvae: high frequencies of aneuploid cells and abnormal anaphase figures, in which chromatids may lag, form bridges, or completely fail to separate. Surviving homozygous adults are sterile, and show cuticular defects associated with cell death, i.e., roughened eyes, sparse abdominal bristles, and notched wing margins. The morphological process of spermatogenesis is largely unaffected and motile sperm are produced, but meiocyte aneuploidy is common. The nature of the observed abnormalities in mitotic cells suggests that the reduced fidelity of chromosome transmission to the daughter cells is due to a failure in a mechanism involved in assuring the proper release of sister chromatids.", "doi": "10.1083/jcb.109.6.2951", "pmcid": "PMC2115894", "issn": "0021-9525", "publisher": "Rockefeller University Press", "publication": "Journal of Cell Biology", "publication_date": "1989-12-01", "series_number": "6", "volume": "109", "issue": "6", "pages": "2951-2961" }, { "id": "authors:1f0s0-qw221", "collection": "authors", "collection_id": "1f0s0-qw221", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351295", "type": "article", "title": "PCR amplification of DNA microdissected from a single polytene chromosome band: a comparison with conventional microcloning", "author": [ { "family_name": "Saunders", "given_name": "Robert D. C.", "clpid": "Saunders-R-D-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Ashburner", "given_name": "Michael", "clpid": "Ashburner-M" }, { "family_name": "Siden-Kiamos", "given_name": "Inga", "clpid": "Siden-Kiamos-I" }, { "family_name": "Louis", "given_name": "Christos", "clpid": "Louis-Christos" }, { "family_name": "Monastirioti", "given_name": "Maria", "clpid": "Monastirioti-M" }, { "family_name": "Savakis", "given_name": "Charalambos", "clpid": "Savakis-C" }, { "family_name": "Kafatos", "given_name": "Fotis", "clpid": "Kafatos-F-C" } ], "abstract": "A novel alternative to microcloning for the production of region specific chromosomal DNA is described. In this method, 'microamplification', single bands are dissected from polytene chromosomes and digested with Sau3A. Oligonucleotide adaptors are ligated to these fragments to provide convenient priming sites for polymerase chain reaction amplification. In this way, as much as 1\u03bcg of DNA can be amplified from a single band. Probes made from PCR amplified DNA from two such dissections have been used to probe cloned DNA form a 100kb chromosome walk. Whereas conventional microcloning has generated cloned EcoRI fragments corresponding to 3\u20134kb of the walk, the PCR probes cover greater than 90% of this chromosomal region. Thus microamplification is significantly more effective than microcloning in providing probes for establishing chromosomal walks.", "doi": "10.1093/nar/17.22.9027", "pmcid": "PMC335111", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1989-11-25", "series_number": "22", "volume": "17", "issue": "22", "pages": "9027-9037" }, { "id": "authors:yrpw7-tbr71", "collection": "authors", "collection_id": "yrpw7-tbr71", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-145241560", "type": "article", "title": "Cloning and chromosomal localization of Drosophila cDNA encoding the catalytic subunit of protein phosphatase 1\u03b1. High conservation between mammalian and insect sequences", "author": [ { "family_name": "Dombr\u00e1di", "given_name": "Viktor", "clpid": "Dombr\u00e1di-V" }, { "family_name": "Axton", "given_name": "J. Myles", "clpid": "Axton-J-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Cohen", "given_name": "Patricia T. W.", "clpid": "Cohen-P-T-W" } ], "abstract": "A 1.2\u2010kb clone containing the full coding sequence of a protein phosphatase 1 catalytic subunit has been isolated from a Drosophila head cDNA library. It encodes a polypeptide of 302 amino acids with a molecular mass of 34.5 kDa. The predicted protein sequence is 92% identical (94% similar) to rabbit protein phosphatase 1\u03b1 (PP\u20101\u03b1) demonstrating strict conservation of the phosphatase catalytic subunit over a considerable evolutionary distance. Abundant 1.6\u2010kb and 2.5\u2010kb mRNA transcripts were detected troughout Drosophila development. The clone hybridised to four sites on Drosophila salivary gland polytene chromosomes. The major site is at 87B6\u201012 on the right arm of chromosome 3. In addition, there are three secondary sites, one on the same chromosome at 96A2\u20105 and two on the X chromosome at 9C1\u20102 and 13C1\u20102. Isolation of a further cDNA clone, hybridising to 9C1\u20102 and encoding part of the catalytic subunit 88% similar to Drosophila PP\u20101\u03b1, proves the existence of at least two transcriptionally active genes for protein phosphatase 1.", "doi": "10.1111/j.1432-1033.1989.tb21089.x", "issn": "0014-2956", "publisher": "Wiley", "publication": "European Journal of Biochemistry", "publication_date": "1989-08", "series_number": "3", "volume": "183", "issue": "3", "pages": "603-610" }, { "id": "authors:brp0k-abp90", "collection": "authors", "collection_id": "brp0k-abp90", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626832", "type": "article", "title": "Molecular cloning and chromosomal localization of a novel Drosophila protein phosphatase", "author": [ { "family_name": "Dombr\u00e1di", "given_name": "Viktor", "clpid": "Dombr\u00e1di-V" }, { "family_name": "Axton", "given_name": "J. Myles", "clpid": "Axton-J-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Cohen", "given_name": "Patricia T. W.", "clpid": "Cohen-P-T-W" } ], "abstract": "A 1.0 kilobase cDNA coding for the complete amino acid sequence of a putative protein phosphatase (314 amino acid residues, molecular mass 36 kDa) has been isolated from a Drosophila head cDNA library. The cDNA hybridises to a single site on the right arm of the second chromosome at cytological position 55A1\u20133. The deduced sequence of the protein, designated protein phosphatase\u2010Y, is homologous to the catalytic subunits of Drosophila and rabbit protein phosphatase\u2010 1\u03b1 (64 and 59% identity, respectively) and rabbit protein phosphatase\u20102A (39% identity). These and other comparisons demonstrate that this novel enzyme is not the Drosophila counterpart of mammalian protein phosphatases 1, 2A, 2B, 2C or X.", "doi": "10.1016/0014-5793(89)81377-8", "issn": "0014-5793", "publisher": "Federation of European Biochemical Societies", "publication": "FEBS Letters", "publication_date": "1989-04-24", "series_number": "2", "volume": "247", "issue": "2", "pages": "391-395" }, { "id": "authors:41grp-bbk28", "collection": "authors", "collection_id": "41grp-bbk28", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150130107", "type": "article", "title": "Mitosis in Drosophila", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Drosophila is an attractive organism in which to study both the rapid rounds of mitosis typical of embryonic development in many species, and the longer cell cycles of diploid tissues later in development. Mutations in genes essential for mitosis in Drosophila may result in lethality in late embryonic, larval or pupal stages of development. In addition, mutations in many genes required for the nuclear divisions of early embryogenesis have been found in screens for female sterility. The mitotic mutations have phenotypes indicative of lesions at a variety of mitotic stages. A combined molecular and genetic analysis of these genes has the potential to unravel the complex set of protein-protein interactions that occur in this dynamic process.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1989-02", "series_number": "2", "volume": "92", "issue": "2", "pages": "137-146" }, { "id": "authors:c7wqz-4xp59", "collection": "authors", "collection_id": "c7wqz-4xp59", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200819-121045051", "type": "article", "title": "Monoclonal antibodies to a proenkephalin A fusion peptide synthesized in Escherichia coli recognize novel proenkephalin A precursor forms", "author": [ { "family_name": "Spruce", "given_name": "Barbara A.", "clpid": "Spruce-B-A" }, { "family_name": "Jackson", "given_name": "Susan", "clpid": "Jackson-Susan" }, { "family_name": "Lowry", "given_name": "Philip J.", "clpid": "Lowry-P-J" }, { "family_name": "Lane", "given_name": "David P.", "clpid": "Lane-D-P" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Monoclonal antibodies have been generated to a chimeric peptide comprised of Escherichia coli beta-galactosidase fused to the amino acid sequence 69-207 of human preproenkephalin A. Two monoclonal antibodies, PE-1 and PE-2, were identified by their ability to recognize the same segment of proenkephalin A fused to the cII gene product of the E. coli bacteriophage lambda. The binding domains of PE-1 and PE-2 have been broadly located, with respect to the primary translation product, within the amino acid sequences 152-207 and 84-131, respectively. Immunoblot analysis of total bovine adrenomedullary chromaffin granule lysate reveals PE-1 and PE-2 immunoreactive forms of observed molecular mass 35, 33, 29, 24, 22, and 15 kDa, and an 18-kDa PE-1 immunoreactive form. Separation of granule membranes from their contents reveals differential membrane association of these high molecular weight polypeptides. There is preliminary evidence that PE-1 may be detecting a subset of polypeptides where shortening from the NH2 terminus has occurred. We postulate that the 35-kDa form represents the intact bovine enkephalin precursor of predicted molecular mass 27.3 kDa. This experimental approach should be generally applicable to the generation of antibodies which will recognize intact peptide precursors together with their post-translational cleavage products.", "issn": "0021-9258", "publisher": "American Society for Biochemistry and Molecular Biology", "publication": "Journal of Biological Chemistry", "publication_date": "1988-12-25", "series_number": "36", "volume": "263", "issue": "36", "pages": "19788-19795" }, { "id": "authors:r3dbw-rv840", "collection": "authors", "collection_id": "r3dbw-rv840", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170351129", "type": "article", "title": "Analysis of the Drosophila rDNA promoter by transient expression", "author": [ { "family_name": "Hayward", "given_name": "David C.", "clpid": "Hayward-D-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have examined the expression of the bacterial gene chloramphenicol acetyl transferase (CAT) under the control of the Drosophila rDNA promoter following transfection into Drosophila tissue culture cells. Constructs having an entire NTS, corresponding to approximately 3640 base pairs of upstream rDNA sequence, or constructs with 306 base pairs of upstream sequence respectively, are transcribed at 5 fold or 2 fold higher levels than a construct with 43 base pairs of upstream DNA. In co-transfection experiments, the construct with the entire NTS competes for transcription 20 fold more effectively than the construct with 306 base pairs of upstream sequence. Constructs having either 72 base pairs or 60 base pairs of upstream rDNA sequences, on the other hand, are transcribed very much less efficiently than constructs with either 306 bp or with only 43 bp of upstream DNA. These sequences, which reduce levels of rDNA transcription in the absence of additional upstream DNA, lie in a region in which the rDNA promoter differs from its duplications within the NTS.", "doi": "10.1093/nar/16.10.4253", "pmcid": "PMC336628", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1988-05-25", "series_number": "10", "volume": "16", "issue": "10", "pages": "4253-4268" }, { "id": "authors:matmj-qwr64", "collection": "authors", "collection_id": "matmj-qwr64", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200930-144645910", "type": "article", "title": "Cloning of a gene encoding an antigen associated with the centrosome in Drosophila", "author": [ { "family_name": "Whitfield", "given_name": "W. G. F.", "clpid": "Whitfield-W-G-F" }, { "family_name": "Millar", "given_name": "S. E.", "clpid": "Millar-Sarah-E" }, { "family_name": "Saumweber", "given_name": "H.", "clpid": "Saumweber-H" }, { "family_name": "Frasch", "given_name": "M.", "clpid": "Frasch-M" }, { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The monoclonal antibody Bx63 recognizes a centrosomal antigen of Drosophila melanogaster by indirect immunofluorescence and identifies two proteins, with apparent molecular weights of 185 x 10\u00b3 and 66 x 10\u00b3, on Western blots. We have used this antibody to isolate five clones (\u03bbcs1, -2, -3, -4 and \u03bbj63) from \u03bbgt11 expression libraries of Drosophila DNA. Using polyclonal anti-centrosomal sera raised against both immunoaffinity-purified Bx63 antigen and electrophoretically purified fusion protein from clone \u03bbcs3, we have demonstrated that the fusion proteins encoded by four of these clones (\u03bbcs1-4) share at least two epitopes with the 185 x 10\u00b3 M_r centrosomal antigen. This indicates that clones \u03bbcs1-4 contain DNA from the gene coding for this protein. The four clones are independent isolates from a single chromosomal site, which we show by in situ hybridization to correspond with salivary gland chromosome region 88E 4-8. A low-abundance transcript of approximately 4.0 x 10\u00b3 bases corresponding to the cloned gene is detected in all stages of the Drosophila life-cycle.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1988-04", "series_number": "4", "volume": "89", "issue": "4", "pages": "467-480" }, { "id": "authors:3yfaz-mt835", "collection": "authors", "collection_id": "3yfaz-mt835", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150331059", "type": "article", "title": "polo, a mitotic mutant of Drosophila displaying abnormal spindle poles", "author": [ { "family_name": "Sunkel", "given_name": "Claudio E.", "clpid": "Sunkel-C-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Neuroblast cells in larvae homozygous for mutant alleles of the locus polo show a high frequency of metaphases in which the chromosomes have a circular arrangement, and anaphase figures in which chromosomes appear to be randomly oriented with respect to at least one of the spindle poles. These defects appear to lead to the production of polyploid cells. Sex chromosome disjunction is affected in male meiosis, primarily in the second division, and the meiotic spindles of living cells are abnormal. One allele is a larval lethal, whereas another is semi-lethal with about 7% of homozygotes surviving as adults. Embryos from homozygous polo females have aberrant mitotic spindles that are highly branched and have broad poles. Immunofluorescence studies with an antibody that recognizes an antigen associated with the centrosome indicate that the organization of this organelle is disrupted in the mutant embryos.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1988-01", "series_number": "1", "volume": "89", "issue": "1", "pages": "25-38" }, { "id": "authors:qfszw-bc646", "collection": "authors", "collection_id": "qfszw-bc646", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-145241670", "type": "article", "title": "Cis-acting sequences sufficient for correct tissue and temporal specificity of larval serum protein 1 genes of Drosophila", "author": [ { "family_name": "Delaney", "given_name": "Stephen J.", "clpid": "Delaney-S-J" }, { "family_name": "Sunkel", "given_name": "Claudio E.", "clpid": "Sunkel-C-E" }, { "family_name": "Genova-Seminova", "given_name": "Ginka K.", "clpid": "Genova-Seminova-G-K" }, { "family_name": "Davies", "given_name": "Jane E.", "clpid": "Davies-Jane-E" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have constructed hybrid genes in which the coding region of the bacterial gene chloramphenicol acetyl transferase (CAT) has been linked to varying lengths of upstream sequences of Drosophila genes for larval serum sequence 1 (LSP1). These have been inserted into a P\u2010element transformation vector and subsequently transferred into the germ\u2010line of recipient flies. Transformants carrying the CAT gene linked to 1650 bp, 570 bp or 377 bp of upstream LSP1\u03b1 sequences, or 745 bp or 471 bp of upstream \u03b2 sequences express CAT with the same developmental and tissue specificity as the endogenous LSP1 genes. Constructs having only 66 bp of upstream LSP1\u03b2 sequences, however, show extremely low levels of CAT expression in tissues and at developmental stages in which LSP1 is not expressed. We discuss the significance of short regions of homology between the DNA upstream of the \u03b1 and \u03b2 genes, which lie within the regions identified by the transformation experiments as being required for the cis\u2010regulation of LSP1 synthesis.", "doi": "10.1002/j.1460-2075.1987.tb02722.x", "pmcid": "PMC553858", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "1987-12", "series_number": "12", "volume": "6", "issue": "12", "pages": "3849-3854" }, { "id": "authors:wpqhg-cxc14", "collection": "authors", "collection_id": "wpqhg-cxc14", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-154703075", "type": "article", "title": "Expression of HLA class II antigens and secretion of interleukin-1 by monocytes and macrophages from adults and neonates", "author": [ { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Brownstein", "given_name": "D.", "clpid": "Brownstein-D" }, { "family_name": "Burchett", "given_name": "S.", "clpid": "Burchett-S" }, { "family_name": "Larsen", "given_name": "A.", "clpid": "Larsen-A" }, { "family_name": "Wilson", "given_name": "C. B.", "clpid": "Wilson-C-B" } ], "abstract": "HLA class II antigen expression and IL-1 production by mononuclear phagocytes are important for antigen-stimulated T-cell activation. We examined these surface antigens and a monocyte marker antigen on fresh cord and adult blood monocytes, macrophages (M\u03c6) derived from monocytes in vitro, human placental (fetal) M\u03c6, from adult women. By FACS analysis, we found less DR on cord blood monocytes (80 \u00b1 7) than on adult monocytes (96 \u00b1 1) with greater heterogeneity in density of DR due to a weakly staining subpopulation of cord monocytes. There were markedly fewer DR and DQ positive placental M\u03c6, 62 \u00b1 11% and 19 \u00b1 3%, compared to adult peritoneal M\u03c6, 91 \u00b1 11% and 87 \u00b1 13%. DQ was more intense on peritoneal M\u03c6 than on any other cell type. Fresh cord monocytes secreted equal or greater amounts of interleukin-1 (IL-1) in response to lipopolysaccharide (LPS) or Group B streptococci than adult monocytes, although results with individual preparations varied. By Northern blot analysis, LPS-stimulated cord blood and adult monocytes contained similar amounts of IL-1\u03b1, IL-1\u03b2 and DR\u03b1 mRNA. Each placental M\u03c6 preparation secreted IL-1 (200 \u00b1 85 U/ml to LPS). Peritoneal M\u03c6 preparations from women in the pre-luteal phase did not release detectable IL-1, whereas those from women in the post-luteal phase released as much as monocytes. Cultured monocytes failed to secrete IL-1 and expressed less DQ than fresh monocytes. Exposure to IFN gamma augmented IL-1 release by adult and cord cells and DQ expression on cord cells. These data indicate that class II antigen expression and IL-1 secretion by mononuclear phagocytes are only in part co-ordinately modulated. The differences between placental (fetal) M\u03c6 and adult peritoneal M\u03c6 may reflect both tissue-specific differences and generally diminished class II antigen expression on fetal and neonatal mononuclear phagocytes.", "pmcid": "PMC1453376", "issn": "0019-2805", "publisher": "British Society for Immunology", "publication": "Immunology", "publication_date": "1987-06", "series_number": "2", "volume": "61", "issue": "2", "pages": "195-201" }, { "id": "authors:n6vgy-7m092", "collection": "authors", "collection_id": "n6vgy-7m092", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150413759", "type": "article", "title": "The distribution of a 'mitosis-specific' antigen during Drosophila development", "author": [ { "family_name": "Millar", "given_name": "Sarah E.", "clpid": "Millar-Sarah-E" }, { "family_name": "Freeman", "given_name": "Matthew", "clpid": "Freeman-Matthew" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have used MPM-2, a monoclonal antibody raised against mitotic HeLa cells, to stain a Drosophila cell line, whole mounts of Drosophila embryos, and sectioned tissue from embryonic and larval stages of development. MPM-2 recognizes a major phosphoprotein of approximately 125 X 10\u00b3 M_r in Drosophila tissue culture cells that, like the mammalian MPM-2 antigen, appears to be recognized only in mitotic cells. During early embryogenesis, when the embryonic nuclei divide as a syncytium with a very short nuclear division time, MPM-2 antigen is observed within the spindle compartment at all stages of the nuclear division cycle. Upon cellularization of the embryo and lengthening of the duration of the cycle, the antigen is predominantly seen in mitotic cells. Drosophila larvae contain both diploid and polytene tissues: in diploid tissue MPM-2 staining is specifically observed over mitotic cells, as expected from its distribution in cellularized embryos. Surprisingly, antigen is also detected in the nuclei of polytene cells that replicate their DNA but do not undergo mitosis.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1987-02", "series_number": "1", "volume": "87", "issue": "1", "pages": "95-104" }, { "id": "authors:kf05k-jrw13", "collection": "authors", "collection_id": "kf05k-jrw13", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150515149", "type": "article", "title": "Nuclear antigens follow different pathways into daughter nuclei during mitosis in early Drosophila embryos", "author": [ { "family_name": "Frasch", "given_name": "Manfred", "clpid": "Frasch-M" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Saumweber", "given_name": "Harald", "clpid": "Saumweber-H" } ], "abstract": "In the early embryonic development of Drosophila melanogaster, there is a series of 13 rapid and highly synchronous nuclear divisions. We have used a collection of monoclonal antibodies to follow the re-distribution of nuclear antigens into daughter nuclei at this developmental stage by indirect immunofluorescence microscopy. The antigens fall into several categories in terms of the pathways that are followed at mitosis. At one extreme is a group of antigens that remains continuously associated with the DNA throughout all the mitotic phases. At the other extreme, another group of antigens is excluded from the nucleus at prophase, and does not associate with the nucleus again until late telophase. One antigen, which becomes incorporated into the nucleolus at cellularization after the thirteenth division, becomes associated with the chromosomes during mitosis, but not until anaphase. Several different antibodies stain a diamond-shaped compartment that develops over the spindle at anaphase. The distribution of antigens within this spindle compartment shows some variation: one antigen appears to be present at higher concentrations in the central region of the spindle; others appear in three quite distinct areas corresponding to the positions of the new daughter nuclei and the old parental nucleus. Yet another antibody gives uniform staining of the spindle compartment. This antibody also recognizes a protein present in centrosomes.", "issn": "0021-9533", "publisher": "Company of Biologists", "publication": "Journal of Cell Science", "publication_date": "1986-06", "series_number": "1", "volume": "82", "issue": "1", "pages": "155-172" }, { "id": "authors:d1xf0-qgf69", "collection": "authors", "collection_id": "d1xf0-qgf69", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170350920", "type": "article", "title": "Site specific insertion of a type I rDNA dement into a unique sequence in the Drosophila melanogaster genome", "author": [ { "family_name": "Browne", "given_name": "Michael J.", "clpid": "Browne-Michael-J" }, { "family_name": "Read", "given_name": "Christopher A.", "clpid": "Read-C-A" }, { "family_name": "Roiha", "given_name": "Heli", "clpid": "Roiha-H" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We describe a cloned segment of unique DNA from the Oregon R strain of Drosophila melanogaster that contains a short type I insertion of the kind principally found within rDNA. The predominant type I rDNA insertion is 5kb in length, but there are also a co-terminal sub-set of shorter type I elements that share a common right hand junction with the rDNA. The insertion that we now describe is another member of this sub-set. The right hand junction of the type I sequence with the unique DNA is identical to the right hand junction of the type I sequences with rDNA. There is no significant feature within the insertion sequence that could have determined the position of the left junction with the sequence into which it is inserted. Like the corresponding short type I insertions in rDNA, the insertion into the unique DNA is flanked on both sides by a duplicated sequence, which in this case is 10 base pairs long. The cloning of a sequence corresponding to the uninterrupted unique location was facilitated by the observation that the Karsnas strain of D. melanoqaster contains only uninterrupted sequences of this kind. The duplicated sequence at the target site for the insertion is only present as a single copy in the uninterrupted DNA. The sequence of the target site for the insertion (ACTGTTCT) in the unique segment shows a striking homology to the target in rDNA (ACTGTCCC).", "doi": "10.1093/nar/12.23.9111", "pmcid": "PMC320441", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1984-12-11", "series_number": "23", "volume": "12", "issue": "23", "pages": "9111-9122" }, { "id": "authors:4bwj2-kwg69", "collection": "authors", "collection_id": "4bwj2-kwg69", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-155619512", "type": "article", "title": "Widely differing degrees of sequence conservation of the two types of rDNA insertion within the melanogaster species sub-group of Drosophila", "author": [ { "family_name": "Roiha", "given_name": "Heli", "clpid": "Roiha-H" }, { "family_name": "Read", "given_name": "Christopher A.", "clpid": "Read-C-A" }, { "family_name": "Browne", "given_name": "Michael J.", "clpid": "Browne-Michael-J" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have examined the distribution of sequences homologous to the type I and type II rDNA insertions of Drosophila melanogaster in its sibling species. Each of the six species we have examined has sequences homologous to the type I insertion, which have undergone extensive divergence by the criterion of their EcoRI, BstI and HindIII restriction patterns. We have isolated cosmid clones containing type I sequences from D. simulans and D. mauritiana, the two species most closely related to D. melanogaster. Southern hybridisation analysis of these clones indicates that, as in D. melanogaster, the type I sequences can exist independently of rDNA and can also dissociate to give sub\u2010components homologous to the right hand segment of the D. melanogaster type I insertion. The type II sequences, on the other hand are present in five out of the six species, but their restriction endonuclease cleavage profile is highly conserved. The differences in the degree of conservation of the two types of insertion sequence are discussed.", "doi": "10.1002/j.1460-2075.1983.tb01491.x", "pmcid": "PMC555176", "issn": "0261-4189", "publisher": "European Molecular Biology Organization", "publication": "EMBO Journal", "publication_date": "1983-05", "series_number": "5", "volume": "2", "issue": "5", "pages": "721-726" }, { "id": "authors:b8kvg-pz314", "collection": "authors", "collection_id": "b8kvg-pz314", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170350833", "type": "article", "title": "Transcription of the 'non-transcribed' spacer of Drosophila melanogaster rDNA", "author": [ { "family_name": "Miller", "given_name": "J. Ross", "clpid": "Miller-J-R" }, { "family_name": "Hayward", "given_name": "David C.", "clpid": "Hayward-D-C" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We have detected a set of transcripts in Drosophila melanogaster cells which are homologous to repeating elements within the 'non-transcribed' spacer region of rDNA. The RNA molecules range from 240 to 1680 nucleotides, differing in length by an integral value of 240 nucleotides. We have sequenced several AluI fragments which characterise the main 240 nucleotide repeating element. We find that each of these fragments contain a segment of approximately 50 nucleotides, which is homologous to the transcription initiation site for pre-rRNA.", "doi": "10.1093/nar/11.1.11", "pmcid": "PMC325687", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1983-01-11", "series_number": "1", "volume": "11", "issue": "1", "pages": "11-19" }, { "id": "authors:smk1k-cv573", "collection": "authors", "collection_id": "smk1k-cv573", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170350737", "type": "article", "title": "The structure and expression of the preproenkephalin gene", "author": [ { "family_name": "Legon", "given_name": "Steve", "clpid": "Legon-S" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hughes", "given_name": "John", "clpid": "Hughes-John" }, { "family_name": "Lowry", "given_name": "Philip J.", "clpid": "Lowry-P-J" }, { "family_name": "Rigby", "given_name": "Peter W. J.", "clpid": "Rigby-P-W-J" }, { "family_name": "Watson", "given_name": "Christine J.", "clpid": "Watson-Christine-J" } ], "abstract": "Enkephalins are pentapeptides with opioid activity which are found in a wide variety of tissues. Studies of enkephalin-containing peptides from the adrenal gland have established that the mature pentapeptides are derived by proteolytic processing of a precursor protein. We have shown that human adrenal medullary tumours contain mRNA which can be translated in vitro to yield a single major enkephalin precursor. The sequence of cloned cDNA shows that the preproenkephal in mRNA encodes four copies of met-enkephalin, two copies of the met-enkephalin extended sequences and one copy of leuenkephalin; each copy is flanked by paired basic amino acids which are presumably recognised by the processing protease. We have used the cloned human cDNA as a hybridization probe to detect the corresponding mRNAs in rat adrenal grand and, in smaller amounts, in rat brain. We have been unable to detect in brain any other cross-hybridising mRNAs which might encode other putative precursor proteins.", "doi": "10.1093/nar/10.24.7905", "pmcid": "PMC327058", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1982-12-20", "series_number": "24", "volume": "10", "issue": "24", "pages": "7905-7918" }, { "id": "authors:avpdp-n1678", "collection": "authors", "collection_id": "avpdp-n1678", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-143650238", "type": "article", "title": "Gene amplification in Rhynchosciara salivary gland chromosomes", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Zaha", "given_name": "Arnaldo", "clpid": "Zaha-Arnaldo" }, { "family_name": "Stocker", "given_name": "Ann Jacob", "clpid": "Stocker-A-J" }, { "family_name": "Santelli", "given_name": "Roberto V.", "clpid": "Santelli-R-V" }, { "family_name": "Pueyo", "given_name": "Manuel T.", "clpid": "Pueyo-M-T" }, { "family_name": "De Toledo", "given_name": "Sonia Maria", "clpid": "De-Toledo-S-M" }, { "family_name": "Lara", "given_name": "Francisco J. S.", "clpid": "Lara-F-J-S" } ], "abstract": "Late in the fourth larval instar, several regions of the Rhynchosciara americana salivary gland chromosomes undergo \"DNA puffing.\" We have constructed a library of cloned cDNAs synthesized from poly(A)\u207aRNA isolated from salivary glands during the period of development when the DNA puffs are active. From this library we have studied clones representative of three genes active during this period but not active at earlier developmental periods of the gland. One of these genes is not amplified during the developmental process and encodes a 0.6-kilobase RNA molecule. The other two genes are located within the DNA-puff sites C3 and C8 and encode 1.25-kilobase and 1.95-kilobase RNA molecules, respectively. We estimate from the quantitation of transfer hybridization experiments that each of these genes undergoes 16-fold amplification during DNA puffing.", "doi": "10.1073/pnas.79.9.2947", "pmcid": "PMC346325", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "1982-05-01", "series_number": "9", "volume": "79", "issue": "9", "pages": "2947-2951" }, { "id": "authors:gzkyn-ezp36", "collection": "authors", "collection_id": "gzkyn-ezp36", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170350585", "type": "article", "title": "Duplicated rDNA sequences of variable lengths flanking the short type I insertions in the rDNA of Drosophila melanogaster", "author": [ { "family_name": "Roiha", "given_name": "Heli", "clpid": "Roiha-H" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "We describe cloned segments of rDNA that contain short type I insertions of differing lengths. These insertions represent a coterminal subset of sequences from the right hand side of the major 5kb type I insertion. Three of these shorter insertions are flanked on both sides by a short sequence present as a single copy in uninterrupted rDNA units. The duplicated segment is 7, 14 and 15 nucleotides in the different clones. In this respect, the insertions differ from the 5kb type I insertion, where the corresponding sequence is found only at the right hand junction and where at the left hand side there is a deletion of 9 nucleotides of rDNA (Roiha et al., 1981). One clone is unusual in that it contains two type I insertions, one of which is flanked by a 14 nucleotide repeat. The left hand junction of the second insertion occurs 380 nucleotides downstream in the rDNA unit from the first. It has an identical right hand junction to the other elements and the 380 nucleotide rDNA sequence is repeated on both sides of the insertion. We discuss the variety of sequence rearrangements of the rDNA which flank type I insertions.", "doi": "10.1093/nar/9.21.5521", "pmcid": "PMC327541", "issn": "0305-1048", "publisher": "Oxford University Press", "publication": "Nucleic Acids Research", "publication_date": "1981-11-11", "series_number": "21", "volume": "9", "issue": "21", "pages": "5521-5532" }, { "id": "authors:y6ws4-ybp72", "collection": "authors", "collection_id": "y6ws4-ybp72", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170354415", "type": "article", "title": "Cloned segment of Drosophila melanogaster rDNA containing new types of sequence insertion", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "A cloned 14.3-kbase segment of Drosophila melanogaster rDNA (Dm207) is described in which only a 4-kbase region is homologous to a cloned 17-kbase rDNA repeating unit, Dm103; this 4-kbase region consists of part of the 28S rRNA gene and most but not all of the adjacent transcribed spacer that normally connects the 18S and 28S genes. The transcribed spacer in Dm207 is interrupted by a 2.2-kbase stretch of DNA that does not contain any 18S gene sequences. At the other end of the 4-kbase homology, the 28S gene is interrupted by an 8.1-kbase stretch of DNA at a position equivalent to the site of the 28S insertion found in the 17-kbase units. The question of whether the 2.2-kbase and 8.1-kbase interrupter segments in Dm207 derive from longer insertions into the transcribed spacer and 28S genes of a very long repeating unit (greater than or equal to 22 kbases) or represent a region of the chromosomal DNA into which a 4-kbase fragment of rDNA has been inserted is discussed.", "doi": "10.1073/pnas.74.11.4932", "pmcid": "PMC432071", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "1977-11", "series_number": "11", "volume": "74", "issue": "11", "pages": "4932-4936" }, { "id": "authors:hfkjm-qh118", "collection": "authors", "collection_id": "hfkjm-qh118", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150626940", "type": "article", "title": "5.8 S and 2 S rDNA is located in the 'transcribed spacer' region between the 18 S and 26 S rRNA genes in Drosophila melanogaster", "author": [ { "family_name": "Jordan", "given_name": "Bertrand R.", "clpid": "Jordan-B-R" }, { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "In Drosophila melanogaster, two small RNA species are found hydrogen bonded to 26 S rRNA:5.8 S rRNA, approximately 125 nucleotides long, and 2 S rRNA, 30 nucleotides long [1]. Evidence from pulse-chase experiments shows that they arise as the result of post transcriptional processing of 26 S RNA, and that the corresponding cleavages occur in the cytoplasm after the central cleavage of the 26 S molecule which occurs in the nucleus [1]. These results do not define completely the architecture of the 26 S molecule and a number of different models remain possible (fig.1). If it is assumed, by analogy with Xenopus laevis [2] that 5.8 S rRNA is coded by a DNA region located between the genes for 18 S and 26 S rRNAs, then class (c) models can be excluded. The experiments reported here examine this question directly by hybridization of \u00b3\u00b2P-1abelled 5.8 S and 2 S RNAs to cloned D. melanogaster rDNA fragments [3].", "doi": "10.1016/0014-5793(77)80321-9", "issn": "0014-5793", "publisher": "Federation of European Biochemical Societies", "publication": "FEBS Letters", "publication_date": "1977-06-01", "series_number": "2", "volume": "78", "issue": "2", "pages": "271-274" }, { "id": "authors:vy105-bfm57", "collection": "authors", "collection_id": "vy105-bfm57", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163116690", "type": "article", "title": "A novel arrangement of the 18S and 28S sequences in a repeating unit of drosophila melanogaster rDNA", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "Hogness", "given_name": "David S.", "clpid": "Hogness-D-S" } ], "abstract": "The sequences corresponding to the 18S and 28S rRNAs have been mapped within a cloned 17 kilobase (kb) fragment formed by Eco R1 cleavage of Drosophila melanogaster rDNA. This fragment, Dm103, represents the longer of two major types of repeating units that are present in the rDNA of this fly, and was cloned as a hybrid plasmid, pDm103, consisting of Dm103 inserted at the Eco R1 site of the pSC101 vector (Glover et al., 1975). Mapping of the 18S and 28S rDNA in Dm103 was accomplished by quantitative determination of the amount of these rDNAs in each member of an ordered set of restriction fragments obtained by Hind III and Eco R1 cleavage of pDm103. The amounts of 18S and 28S rDNAs were determined by hybridization of the rRNAs to fragments that were purified by cloning, and an unambiguous order of the fragments within pDm103 was established by heteroduplex mapping and from the stoichiometry of the fragment lengths. The resulting map revealed that the 4 kb of 28S rDNA within the long repeating unit represented by Dm103 is divided into two blocks that are separated by 5.4 kb of DNA of unknown function. It is this unusual arrangement of the 28S rDNA that distinguishes the long repeating units (17 kb) from the short units (11.5 kb), whose 4 kb of 28S rDNA is confined to a single block, as is shown in the accompanying paper ((White and Hogness, 1977)). The remainder of the DNA in this long unit appears to be typically arranged, with the 2 kb of 18S rDNA confined to a single block that is separated by about 1 kb from the closest block of 28S rDNA.", "doi": "10.1016/0092-8674(77)90212-4", "issn": "0092-8674", "publisher": "Cell Press", "publication": "Cell", "publication_date": "1977-02", "series_number": "2", "volume": "10", "issue": "2", "pages": "167-176" }, { "id": "authors:baw7t-wca49", "collection": "authors", "collection_id": "baw7t-wca49", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-123400214", "type": "article", "title": "Maintenance and evolution of repeated genes in eukaryotes", "author": [ { "family_name": "Glover", "given_name": "D.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "The genes for 5S RNA and ribosomal RNA are highly repetitive and occur as tandemly repeated clusters within eukaryotic genomes. These genes are separated by so-called spacer sequences which are not transcribed. Two main theories have been proposed to explain the mechanism by which tandemly arranged sequences are kept relatively homogeneous and how the genes and their spacers have evolved together. At the one extreme, are the sudden correction mechanisms such as Callan's \"Master-Slave\" hypothesis in which many genes are simultaneously corrected against a master template. At the other extreme, gradual correction mechanisms have been proposed which involve unequal crossing-over between homologous chromatids in such a way that variants could be spread or eliminated from tandem genes. The spacers of the genes for 5S DNA and rDNA in Xenopus laevis have now been subjected to elegant molecular analysis and this has cast some light on these problems.", "doi": "10.1038/263009a0", "issn": "0028-0836", "publisher": "Nature Publishing Group", "publication": "Nature", "publication_date": "1976-09-02", "series_number": "5572", "volume": "263", "issue": "5572", "pages": "9" }, { "id": "authors:djm4a-hfs11", "collection": "authors", "collection_id": "djm4a-hfs11", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200807-170354628", "type": "article", "title": "Characterization of six cloned DNAs from drosophila melanogaster, including one that contains the genes for rRNA", "author": [ { "family_name": "Glover", "given_name": "David M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" }, { "family_name": "White", "given_name": "Raymond L.", "clpid": "White-R-L" }, { "family_name": "Finnegan", "given_name": "David J.", "clpid": "Finnegan-D-J" }, { "family_name": "Hogness", "given_name": "David S.", "clpid": "Hogness-D-S" } ], "abstract": "pDm plasmids were constructed from D. melanogaster and pSC101 DNAs by a modification of the EcoR1-ligase method which insured that each hybrid molecule contained a single segment of D. melanogaster chromosomal DNA (Dm segment). The sequences in the Dm segments of six cloned pDm DNAs were mapped within the D. melanogaster polytene chromosomes by in situ hybridization, and their repetition frequencies within the Dm segment and within the genome were determined. Four of these segments consist of sequences that are confined to single chromomeric regions in the polytene chromosomes and exhibit little or no repetition. The characteristics of this group, and also two of three Dm segments analyzed earlier (Wensink et al., 1974), are inconsistent with tandem repetition models of the chromomere. By contrast, the other two Dm segments contain moderately repetitive sequences that are located in the heterochromatin. One of these appears to be a segment of the Y chromosome in which about half the sequences are nonrepetitive and half are repeated about 33 times per genome, though they are not repeated within the segment. The second contains the DNA coding for 18 and 28S rRNA.", "doi": "10.1016/0092-8674(75)90023-9", "issn": "0092-8674", "publisher": "Cell Press", "publication": "Cell", "publication_date": "1975-06", "series_number": "2", "volume": "5", "issue": "2", "pages": "149-157" }, { "id": "authors:2869m-stn22", "collection": "authors", "collection_id": "2869m-stn22", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-163116783", "type": "article", "title": "Coupling of polyoma DNA and RNA synthesis", "author": [ { "family_name": "Glover", "given_name": "D. M.", "orcid": "0000-0003-0956-0103", "clpid": "Glover-D-M" } ], "abstract": "Polyoma virus RNA from infected mouse embryo cells was examined by gel electrophoresis and in nucleic acid hybridisation experiments. The extent of representation of the polyoma genome in RNA sequences when cytosine arabinoside is present throughout infection is 30 to 40% of that at late times in infection. When viral DNA synthesis is inhibited during the period in which it is rising to its maximum, the resulting cytoplasmic RNA resembles 'early' RNA both in size and by its behaviour in competition hybridisation experiments.", "doi": "10.1016/0006-291x(74)90815-8", "issn": "0006-291X", "publisher": "Elsevier", "publication": "Biochemical and Biophysical Research Communications", "publication_date": "1974-04-23", "series_number": "4", "volume": "57", "issue": "4", "pages": "1137-1143" } ]