title: Myoblast city, the Drosophila homolog of DOCK180/CED-5, is required in a Rac signaling pathway utilized for multiple developmental processes.
abstract: The Rac and Cdc42 GTPases share several regulators and effectors, yet perform distinct biological functions. The factors determining such specificity in vivo have not been identified. In a mutational screen in Drosophila to identify Rac-specific signaling components, we isolated 11 alleles of myoblast city (mbc). mbc mutant embryos exhibit defects in dorsal closure, myogenesis, and neural development. DOCK180, the mammalian homolog of Mbc, associates with Rac, but not Cdc42, in a nucleotide-independent manner. These results suggest that Mbc is a specific upstream regulator of Rac activity that mediates several morphogenetic processes in Drosophila embryogenesis.
authors.affiliation: Massachusetts General Hospital Cancer Center and Harvard Medical School, Charlestown, Massachusetts 02129 USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Nolan
authors.forename: K
authors.initials: K
authors.lastname: Barrett
authors.forename: Y
authors.initials: Y
authors.lastname: Lu
authors.forename: K Q
authors.initials: KQ
authors.lastname: Hu
authors.forename: S
authors.initials: S
authors.lastname: Vincent
authors.forename: J
authors.initials: J
authors.lastname: Settleman
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D019556:COS Cells; D029742:Caenorhabditis elegans Proteins; D003598:Cytoskeletal Proteins; D004330:Drosophila / Q000196:embryology* / Q000235:genetics; D029721:Drosophila Proteins; D020558:GTP Phosphohydrolases / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D019476:Insect Proteins / Q000235:genetics / Q000502:physiology*; D008565:Membrane Proteins / Q000502:physiology*; D009154:Mutation; D011506:Proteins / Q000378:metabolism / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics*; D020744:rac GTP-Binding Proteins
chemical_list: C111579:CED-5 protein, C elegans; D029742:Caenorhabditis elegans Proteins; D003598:Cytoskeletal Proteins; C099818:DOCK1 protein, human; D029721:Drosophila Proteins; D019476:Insect Proteins; D008565:Membrane Proteins; D011506:Proteins; C107441:mbc protein, Drosophila; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins; D020744:rac GTP-Binding Proteins