title: Destruction of the securin Pds1p occurs at the onset of anaphase during both meiotic divisions in yeast.
abstract: Sister chromatid cohesion is established during DNA replication and depends on a multiprotein complex called cohesin. At the onset of anaphase the cohesive structures that hold sisters together must be destroyed to allow segregation of sisters. In the budding yeast Saccharomyces cerevisiae loss of sister chromatid cohesion depends on a separating protein (separin) called Esp1. At the metaphase to anaphase transition, separin is activated by proteolysis of its inhibitory subunit (securin) called Pds1. This process is mediated by the anaphase promoting complex and an accessory protein Cdc20. In meiosis a single round of DNA replication is followed by two successive rounds of segregation. Thus loss of cohesion is spun out over two divisions. By studying the mechanisms that initiate anaphase in meiotic division we show that the yeast securin Pds1p is present in meiotic nuclei and is destroyed at the onset of each meiotic division. We also show that securin destruction depends on Cdc20p which accumulates within nuclei around the time of Pds1p's disappearance.
authors.affiliation: Vienna Biocenter, Institute of Biochemistry and Molecular Biology, Austria.
authors.forename: S M
authors.initials: SM
authors.lastname: Salah
authors.forename: K
authors.initials: K
authors.lastname: Nasmyth
mesh_terms: D000705:Anaphase / Q000235:genetics*; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002455:Cell Division / Q000235:genetics; D010450:Endopeptidases; D005455:Fluorescent Antibody Technique; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D006720:Homozygote; D008540:Meiosis / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D064249:Securin; D064247:Separase
chemical_list: C577495:CDC20 protein, S cerevisiae; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D009687:Nuclear Proteins; C578004:PDS1 protein, S cerevisiae; D016271:Proto-Oncogene Proteins c-myc; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D064249:Securin; D010450:Endopeptidases; C577986:ESP1 protein, S cerevisiae; D064247:Separase