title: OSD1 promotes meiotic progression via APC/C inhibition and forms a regulatory network with TDM and CYCA1;2/TAM.
abstract: Cell cycle control is modified at meiosis compared to mitosis, because two divisions follow a single DNA replication event. Cyclin-dependent kinases (CDKs) promote progression through both meiosis and mitosis, and a central regulator of their activity is the APC/C (Anaphase Promoting Complex/Cyclosome) that is especially required for exit from mitosis. We have shown previously that OSD1 is involved in entry into both meiosis I and meiosis II in Arabidopsis thaliana; however, the molecular mechanism by which OSD1 controls these transitions has remained unclear. Here we show that OSD1 promotes meiotic progression through APC/C inhibition. Next, we explored the functional relationships between OSD1 and the genes known to control meiotic cell cycle transitions in Arabidopsis. Like osd1, cyca1;2/tam mutation leads to a premature exit from meiosis after the first division, while tdm mutants perform an aberrant third meiotic division after normal meiosis I and II. Remarkably, while tdm is epistatic to tam, osd1 is epistatic to tdm. We further show that the expression of a non-destructible CYCA1;2/TAM provokes, like tdm, the entry into a third meiotic division. Finally, we show that CYCA1;2/TAM forms an active complex with CDKA;1 that can phosphorylate OSD1 in vitro. We thus propose that a functional network composed of OSD1, CYCA1;2/TAM, and TDM controls three key steps of meiotic progression, in which OSD1 is a meiotic APC/C inhibitor.
authors: INRA, UMR1318, Institut Jean-Pierre Bourgin, Versailles, France.
authors: Laurence
authors: L
authors: Cromer
authors: Jefri
authors: J
authors: Heyman
authors: Sandra
authors: S
authors: Touati
authors: Hirofumi
authors: H
authors: Harashima
authors: Emilie
authors: E
authors: Araou
authors: Chloe
authors: C
authors: Girard
authors: Christine
authors: C
authors: Horlow
authors: Katja
authors: K
authors: Wassmann
authors: Arp
authors: A
authors: Schnittger
authors: Lieven
authors: L
authors: De Veylder
authors: Raphael
authors: R
authors: Mercier
mesh_terms: D064173:Anaphase-Promoting Complex-Cyclosome; D000818:Animals; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D059447:Cell Cycle Checkpoints / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics; D056750:Cyclin A1 / Q000235:genetics* / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000235:genetics / Q000378:metabolism; D016213:Cyclins / Q000235:genetics* / Q000378:metabolism; D004843:Epistasis, Genetic; D005718:Gametogenesis / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D053263:Gene Regulatory Networks; D008540:Meiosis / Q000235:genetics*; D051379:Mice; D008938:Mitosis / Q000235:genetics; D009154:Mutation; D009865:Oocytes / Q000378:metabolism; D010766:Phosphorylation; D030821:Plants, Genetically Modified; D015398:Signal Transduction; D043743:Ubiquitin-Protein Ligase Complexes / Q000037:antagonists & inhibitors / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D018797:Cell Cycle Proteins; D056750:Cyclin A1; D016213:Cyclins; C577069:OSD1 protein, Arabidopsis; C557479:TDM1 protein, Arabidopsis; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; C434472:CDKA1 protein, Arabidopsis; D018844:Cyclin-Dependent Kinases