A Role for Cdc2- and PP2A-Mediated Regulation of Emi2 in the Maintenance of CSF Arrest

• DOI: 10.1016/j.cub.2006.12.045
• Publication Date: 2007-02-06T12:56:16Z
• Authors: Qiju Wu; Yanxiang Guo; Ayumi Yamada; Jennifer A. Perry; Michael Z. Wang; Marito Araki; Christopher D. Freel; Jeffrey J. Tung; Wanli Tang; Seth S. Margolis; Peter K. Jackson; Hiroyuki Yamano; Maki Asano; Sally Kornbluth
• Keywords: 0301 basic medicine; DNA, Complementary; Cdc20 Proteins; Recombinant Fusion Proteins; Cell Cycle Proteins; CELLCYCLE; Cyclin B; Anaphase-Promoting Complex-Cyclosome; 03 medical and health sciences; CDC2 Protein Kinase; Okadaic Acid; Phosphoprotein Phosphatases; Animals; Humans; Enzyme Inhibitors; Phosphorylation; Gene Library; 0303 health sciences; Agricultural and Biological Sciences(all); Biochemistry, Genetics and Molecular Biology(all); F-Box Proteins; Ubiquitin-Protein Ligase Complexes; Meiosis; SIGNALING; Proto-Oncogene Proteins c-mos; Oocytes; Protein Binding

Vertebrate oocytes are arrested in metaphase II of meiosis prior to fertilization by cytostatic factor (CSF). CSF enforces a cell cycle arrest by inhibiting the anaphase promoting complex (APC), an E3 ubiquitin ligase that targets Cyclin B for degradation. Although Cyclin B synthesis is ongoing during CSF arrest, constant Cyclin B levels are maintained. To achieve this, oocytes allow continuous slow Cyclin B degradation, without eliminating the bulk of Cyclin B, which would induce release from CSF arrest. However, the mechanism that controls this continuous degradation is not understood.