title: Rop, the Sec1/Munc18 homolog in Drosophila, is required for furrow ingression and stable cell shape during cytokinesis.
abstract: Physically separating daughter cells during cytokinesis requires contraction of an actin-myosin ring and vesicle-mediated membrane addition at the cleavage furrow. To identify vesicle trafficking proteins that function in cytokinesis, we screened deficiencies and mutations of candidate genes by live imaging the mitotic domains of the Drosophila embryo. In embryos homozygous for some of these deficiencies, we observed several cytokinesis phenotypes, including slow furrow ingression and increased membrane blebbing. We also found that cytokinesis required the Sec1/Munc18 homolog Rop, which interacts with syntaxin and mediates exocytosis at the plasma membrane. In a temperature-sensitive Rop mutant (Rop(TS)), the contractile ring disassembled during furrow ingression, indicating that maintenance of the ring required vesicle addition. Furthermore, in some dividing Rop(TS) cells, the shape of the daughter cells became unstable, causing cytokinesis failure. These results further highlight the importance of vesicle trafficking in animal cytokinesis and show that vesicle fusion influences cell shape during cytokinesis.
authors.affiliation: Molecular, Cell and Developmental Biology, University of California at Santa Cruz, Santa Cruz, CA 95064, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: DeBruhl
authors.affiliation: Biology Department, Albion College, Albion, MI 49224, USA.
authors.forename: Roger
authors.initials: R
authors.lastname: Albertson
authors.affiliation: Molecular, Cell and Developmental Biology, University of California at Santa Cruz, Santa Cruz, CA 95064, USA.
authors.forename: Zachary
authors.initials: Z
authors.lastname: Swider
authors.affiliation: Molecular, Cell and Developmental Biology, University of California at Santa Cruz, Santa Cruz, CA 95064, USA sullivan@biology.ucsc.edu.
authors.forename: William
authors.initials: W
authors.lastname: Sullivan
mesh_terms: D000818:Animals; D001692:Biological Transport; D048430:Cell Shape; D048749:Cytokinesis; D029721:Drosophila Proteins / Q000502:physiology*; D004331:Drosophila melanogaster / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D005260:Female; D007814:Larva / Q000166:cytology / Q000378:metabolism; D008297:Male; D009419:Nerve Tissue Proteins / Q000502:physiology*; D008941:Spindle Apparatus / Q000378:metabolism; D022161:Transport Vesicles / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D009419:Nerve Tissue Proteins; C086393:Rop protein, Drosophila
keywords: Cytokinesis; Rop; Sec1/Munc18; Vesicle trafficking