title: Cyclin A2 is required for sister chromatid segregation, but not separase control, in mouse oocyte meiosis.
abstract: In meiosis, two specialized cell divisions allow the separation of paired chromosomes first, then of sister chromatids. Separase removes the cohesin complex holding sister chromatids together in a stepwise manner from chromosome arms in meiosis I, then from the centromere region in meiosis II. Using mouse oocytes, our study reveals that cyclin A2 promotes entry into meiosis, as well as an additional unexpected role; namely, its requirement for separase-dependent sister chromatid separation in meiosis II. Untimely cyclin A2-associated kinase activity in meiosis I leads to precocious sister separation, whereas inhibition of cyclin A2 in meiosis II prevents it. Accordingly, endogenous cyclin A is localized to kinetochores throughout meiosis II, but not in anaphase I. Additionally, we found that cyclin B1, but not cyclin A2, inhibits separase in meiosis I. These findings indicate that separase-dependent cohesin removal is differentially regulated by cyclin B1 and A2 in mammalian meiosis.
authors.affiliation: UPMC Université Paris 06, UMR7622 Laboratoire de Biologie du Développement, 9 quai St. Bernard, Paris 75005, France.
authors.forename: Sandra A
authors.initials: SA
authors.lastname: Touati
authors.forename: Damien
authors.initials: D
authors.lastname: Cladière
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Lister
authors.forename: Ioanna
authors.initials: I
authors.lastname: Leontiou
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Chambon
authors.forename: Ahmed
authors.initials: A
authors.lastname: Rattani
authors.forename: Franziska
authors.initials: F
authors.lastname: Böttger
authors.forename: Olaf
authors.initials: O
authors.lastname: Stemmann
authors.forename: Kim
authors.initials: K
authors.lastname: Nasmyth
authors.forename: Mary
authors.initials: M
authors.lastname: Herbert
authors.forename: Katja
authors.initials: K
authors.lastname: Wassmann
mesh_terms: D000705:Anaphase; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002478:Cells, Cultured; D002503:Centromere / Q000378:metabolism; D002842:Chromatids / Q000378:metabolism*; D020090:Chromosome Segregation; D056751:Cyclin A2 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D056744:Cyclin B1 / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism*; D018386:Kinetochores / Q000378:metabolism; D008540:Meiosis; D008677:Metaphase; D051379:Mice; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D064249:Securin; D064247:Separase
chemical_list: D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D056751:Cyclin A2; D056744:Cyclin B1; D064249:Securin; D018844:Cyclin-Dependent Kinases; D010450:Endopeptidases; D064247:Separase