title: Syntaxin 5 is required for cytokinesis and spermatid differentiation in Drosophila.
abstract: Syntaxin 5 is a Golgi-localized SNARE protein that has been shown to be required for ER-Golgi traffic in yeast and Golgi reassembly following cell division in mammalian cells. Here, we describe the characterization of the Drosophila ortholog of syntaxin 5, dSyx5, and show that, like its mammalian and yeast counterparts, the protein is localized to the Drosophila Golgi and binds to alpha-SNAP. Null mutations in dSyx5 are larval lethal and demonstrate impaired transport of a GFP-tagged membrane protein. A hypomorphic allele of dSyx5 caused by insertion of an EP element results in impenetrant lethality, and escaping adult flies are male sterile. The male sterility results both from failure of germ cells to complete cytokinesis and from defects in spermatid elongation and maturation. Ectopic expression of dSyx5 from the EP element can rescue the cytokinesis defect, but high levels of expression are required to restore maturation and fertility. Together, these results show that dSyx5 is required for the proper function of the Golgi apparatus and that an efficiently functioning Golgi apparatus is required for the steps leading to the completion of cytokinesis and formation of mature sperm.
authors.affiliation: Programme in Cell Biology, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
authors.forename: Hao
authors.initials: H
authors.lastname: Xu
authors.forename: Julie A
authors.initials: JA
authors.lastname: Brill
authors.forename: John
authors.initials: J
authors.lastname: Hsien
authors.forename: Rachel
authors.initials: R
authors.lastname: McBride
authors.forename: Gabrielle L
authors.initials: GL
authors.lastname: Boulianne
authors.forename: William S
authors.initials: WS
authors.lastname: Trimble
mesh_terms: D000818:Animals; D001692:Biological Transport; D002454:Cell Differentiation; D002455:Cell Division; D004330:Drosophila / Q000502:physiology*; D006056:Golgi Apparatus / Q000737:chemistry / Q000502:physiology; D007248:Infertility, Male / Q000209:etiology; D008297:Male; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D050765:Qa-SNARE Proteins; D013087:Spermatids / Q000166:cytology / Q000502:physiology*
chemical_list: D008565:Membrane Proteins; D050765:Qa-SNARE Proteins