title: Disjunction of homologous chromosomes in meiosis I depends on proteolytic cleavage of the meiotic cohesin Rec8 by separin.
abstract: It has been proposed but never proven that cohesion between sister chromatids distal to chiasmata is responsible for holding homologous chromosomes together while spindles attempt to pull them toward opposite poles during metaphase of meiosis I. Meanwhile, the mechanism by which disjunction of homologs is triggered at the onset of anaphase I has remained a complete mystery. In yeast, cohesion between sister chromatid arms during meiosis depends on a meiosis-specific cohesin subunit called Rec8, whose mitotic equivalent, Sccl, is cleaved at the metaphase to anaphase transition by an endopeptidase called separin. We show here that cleavage of Rec8 by separin at one of two different sites is necessary for the resolution of chiasmata and the disjunction of homologous chromosomes during meiosis.
authors.affiliation: Research Institute of Molecular Pathology, University of Vienna, Austria.
authors.forename: S B
authors.initials: SB
authors.lastname: Buonomo
authors.forename: R K
authors.initials: RK
authors.lastname: Clyne
authors.forename: J
authors.initials: J
authors.lastname: Fuchs
authors.forename: J
authors.initials: J
authors.lastname: Loidl
authors.forename: F
authors.initials: F
authors.lastname: Uhlmann
authors.forename: K
authors.initials: K
authors.lastname: Nasmyth
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002503:Centromere / Q000378:metabolism; D020090:Chromosome Segregation; D015825:Chromosomes, Fungal / Q000378:metabolism*; D004706:Endodeoxyribonucleases; D010450:Endopeptidases; D004950:Esterases / Q000235:genetics / Q000502:physiology; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D005800:Genes, Fungal / Q000235:genetics / Q000502:physiology; D017404:In Situ Hybridization, Fluorescence; D008025:Ligases; D008540:Meiosis / Q000235:genetics*; D008938:Mitosis; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D010750:Phosphoproteins; D011499:Protein Processing, Post-Translational; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D064247:Separase; D012689:Sequence Homology, Nucleic Acid; D044767:Ubiquitin-Protein Ligases; D015003:Yeasts / Q000166:cytology* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D000099257:Meiotic Recombination Protein SPO11; D000097722:Cohesins
chemical_list: D018797:Cell Cycle Proteins; D004706:Endodeoxyribonucleases; D010450:Endopeptidases; D004950:Esterases; D005656:Fungal Proteins; D008025:Ligases; D010750:Phosphoproteins; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D064247:Separase; D044767:Ubiquitin-Protein Ligases; D000099257:Meiotic Recombination Protein SPO11; C077081:REC8 protein, S pombe; D000097722:Cohesins; C066066:UBR1 protein, S cerevisiae