title: Cell type-specific translational repression of Cyclin B during meiosis in males.
abstract: The unique cell cycle dynamics of meiosis are controlled by layers of regulation imposed on core mitotic cell cycle machinery components by the program of germ cell development. Although the mechanisms that regulate Cdk1/Cyclin B activity in meiosis in oocytes have been well studied, little is known about the trans-acting factors responsible for developmental control of these factors in male gametogenesis. During meiotic prophase in Drosophila males, transcript for the core cell cycle protein Cyclin B1 (CycB) is expressed in spermatocytes, but the protein does not accumulate in spermatocytes until just before the meiotic divisions. Here, we show that two interacting proteins, Rbp4 and Fest, expressed at the onset of spermatocyte differentiation under control of the developmental program of male gametogenesis, function to direct cell type- and stage-specific repression of translation of the core G2/M cell cycle component cycB during the specialized cell cycle of male meiosis. Binding of Fest to Rbp4 requires a 31-amino acid region within Rbp4. Rbp4 and Fest are required for translational repression of cycB in immature spermatocytes, with Rbp4 binding sequences in a cell type-specific shortened form of the cycB 3' UTR. Finally, we show that Fest is required for proper execution of meiosis I.
authors.affiliation: Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305-5329, USA.
authors.forename: Catherine Craig
authors.initials: CC
authors.lastname: Baker
authors.affiliation: Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305-5329, USA.
authors.forename: Byung Soo
authors.initials: BS
authors.lastname: Gim
authors.affiliation: Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305-5329, USA Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305-5329, USA mtfuller@stanford.edu.
authors.forename: Margaret T
authors.initials: MT
authors.lastname: Fuller
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D015153:Blotting, Western; D064113:CRISPR-Cas Systems; D003001:Cloning, Molecular; D019926:Cyclin B / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D004330:Drosophila / Q000196:embryology* / Q000235:genetics; D029721:Drosophila Proteins / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D047468:Immunoprecipitation; D008297:Male; D008540:Meiosis / Q000502:physiology*; D008856:Microscopy, Fluorescence; D012319:RNA Polymerase II / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013091:Spermatogenesis / Q000502:physiology*
chemical_list: D019926:Cyclin B; D017931:DNA Primers; D029721:Drosophila Proteins; D012319:RNA Polymerase II; C546805:RPB4 protein, Drosophila
keywords: Cyclin B; Drosophila; Meiosis; Spermatogenesis; Translational control