title: Rab11 is required for membrane trafficking and actomyosin ring constriction in meiotic cytokinesis of Drosophila males.
abstract: Rab11 is a small GTPase that regulates several aspects of vesicular trafficking. Here, we show that Rab11 accumulates at the cleavage furrow of Drosophila spermatocytes and that it is essential for cytokinesis. Mutant spermatocytes form regular actomyosin rings, but these rings fail to constrict to completion, leading to cytokinesis failures. rab11 spermatocytes also exhibit an abnormal accumulation of Golgi-derived vesicles at the telophase equator, suggesting a defect in membrane-vesicle fusion. These cytokinesis phenotypes are identical to those elicited by mutations in giotto (gio) and four wheel drive (fwd) that encode a phosphatidylinositol transfer protein and a phosphatidylinositol 4-kinase, respectively. Double mutant analysis and immunostaining for Gio and Rab11 indicated that gio, fwd, and rab11 function in the same cytokinetic pathway, with Gio and Fwd acting upstream of Rab11. We propose that Gio and Fwd mediate Rab11 recruitment at the cleavage furrow and that Rab11 facilitates targeted membrane delivery to the advancing furrow.
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Genetica e Biologia Molecolare, Università di Roma "La Sapienza," 00185 Rome, Italy. mariagrazia.giansanti@uniroma1.it
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Giansanti
authors.forename: Giorgio
authors.initials: G
authors.lastname: Belloni
authors.forename: Maurizio
authors.initials: M
authors.lastname: Gatti
mesh_terms: D000205:Actomyosin / Q000494:pharmacology*; D000818:Animals; D002462:Cell Membrane / Q000187:drug effects* / Q000378:metabolism*; D048749:Cytokinesis / Q000187:drug effects*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000166:cytology* / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism; D008297:Male; D009154:Mutation / Q000235:genetics; D049294:Phospholipid Transfer Proteins / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D000099193:rab11 GTP-Binding Proteins
chemical_list: D000205:Actomyosin; D029721:Drosophila Proteins; D049294:Phospholipid Transfer Proteins; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins; C509515:Vib protein, Drosophila