title: Spindle Assembly and Chromosome Segregation Requires Central Spindle Proteins in Drosophila Oocytes.
abstract: Oocytes segregate chromosomes in the absence of centrosomes. In this situation, the chromosomes direct spindle assembly. It is still unclear in this system which factors are required for homologous chromosome bi-orientation and spindle assembly. The Drosophila kinesin-6 protein Subito, although nonessential for mitotic spindle assembly, is required to organize a bipolar meiotic spindle and chromosome bi-orientation in oocytes. Along with the chromosomal passenger complex (CPC), Subito is an important part of the metaphase I central spindle. In this study we have conducted genetic screens to identify genes that interact with subito or the CPC component Incenp. In addition, the meiotic mutant phenotype for some of the genes identified in these screens were characterized. We show, in part through the use of a heat-shock-inducible system, that the Centralspindlin component RacGAP50C and downstream regulators of cytokinesis Rho1, Sticky, and RhoGEF2 are required for homologous chromosome bi-orientation in metaphase I oocytes. This suggests a novel function for proteins normally involved in mitotic cell division in the regulation of microtubule-chromosome interactions. We also show that the kinetochore protein, Polo kinase, is required for maintaining chromosome alignment and spindle organization in metaphase I oocytes. In combination our results support a model where the meiotic central spindle and associated proteins are essential for acentrosomal chromosome segregation.
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Arunika
authors.initials: A
authors.lastname: Das
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Shital J
authors.initials: SJ
authors.lastname: Shah
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Bensen
authors.initials: B
authors.lastname: Fan
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Daniel
authors.initials: D
authors.lastname: Paik
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: DiSanto
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Hinman
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Jeffry M
authors.initials: JM
authors.lastname: Cesario
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Rachel A
authors.initials: RA
authors.lastname: Battaglia
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854.
authors.forename: Nicole
authors.initials: N
authors.lastname: Demos
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, New Jersey 08854 Department of Genetics, Rutgers, The State University of New Jersey, New Jersey 08854 mckim@rci.rutgers.edu.
authors.forename: Kim S
authors.initials: KS
authors.lastname: McKim
mesh_terms: D000818:Animals; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone / Q000502:physiology; D020090:Chromosome Segregation; D059006:Chromosomes, Insect / Q000502:physiology*; D004330:Drosophila; D029721:Drosophila Proteins / Q000494:pharmacology / Q000502:physiology*; D005260:Female; D020690:GTPase-Activating Proteins / Q000502:physiology; D047908:Intracellular Signaling Peptides and Proteins / Q000502:physiology; D016547:Kinesins / Q000502:physiology; D008297:Male; D008540:Meiosis; D008677:Metaphase; D008869:Microtubule-Associated Proteins / Q000502:physiology; D016296:Mutagenesis; D009865:Oocytes / Q000166:cytology*; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D008941:Spindle Apparatus / Q000502:physiology*; D000077022:Survivin; D020741:rho GTP-Binding Proteins / Q000502:physiology
chemical_list: D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; C412228:Det protein, Drosophila; D029721:Drosophila Proteins; D020690:GTPase-Activating Proteins; C512039:Incenp protein, Drosophila; D047908:Intracellular Signaling Peptides and Proteins; D008869:Microtubule-Associated Proteins; C466086:SUB protein, Drosophila; D000077022:Survivin; C490516:pav protein, Drosophila; C465504:sav protein, Drosophila; C502951:tum protein, Drosophila; C115635:citron-kinase; D017346:Protein Serine-Threonine Kinases; D016547:Kinesins; C511153:Rho1 protein, Drosophila; D020741:rho GTP-Binding Proteins
keywords: Drosophila; chromosome segregation; homolog bi-orientation; meiosis; spindle; synthetic lethal mutation