title: Phosphorylation of RNA-binding protein controls cell cycle switch from mitotic to meiotic in fission yeast.
abstract: Meiosis generates haploid gametes from diploid cells and is an almost universal feature of eukaryotic organisms. But little is known about how the switch from mitotic to meiotic cell cycles is molecularly controlled. In the fission yeast Schizosaccharomyces pombe, inactivation of the protein kinase Pat1(Ran1) upon nutrient deprivation triggers entry into the meiotic cell cycle. Here we show that the RNA-binding protein Mei2 is a substrate of Pat1 kinase and that dephosphorylation of Mei2 is sufficient to switch cells from the mitotic cell cycle into meiosis. Mei2 is localized mainly in the cytoplasm of proliferating cells but is seen as a single spot close to the microtubule organizing centre in prophase nuclei during meiosis. Our results, and others from a metazoan, emphasize the crucial role of RNA-binding proteins in the initiation and execution of meiosis.
authors.affiliation: Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Watanabe
authors.forename: S
authors.initials: S
authors.lastname: Shinozaki-Yabana
authors.forename: Y
authors.initials: Y
authors.lastname: Chikashige
authors.forename: Y
authors.initials: Y
authors.lastname: Hiraoka
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
mesh_terms: D001665:Binding Sites; D002453:Cell Cycle / Q000502:physiology*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008540:Meiosis / Q000502:physiology*; D008938:Mitosis / Q000502:physiology*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins
chemical_list: D005656:Fungal Proteins; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D029702:Schizosaccharomyces pombe Proteins; C088896:mei2 protein, S pombe; D011494:Protein Kinases; C087019:ran1 protein, S pombe; D017346:Protein Serine-Threonine Kinases