Core of basic research: Uses Xenopus laevis oocytes as a model system to decipher the molecular regulatory mechanism of meiosis, providing a core model for understanding vertebrate germ cell maturation. Xenopus oocyte meiosis consists of two consecutive division phases (MI and MII) without interphase: Immature oocytes arrest at the G2 phase; activated by luteinizing hormone (LH) signals, they initiate MI phase with homologous chromosome segregation, then rapidly enter MII phase and arrest at metaphase II (oocyte maturation), waiting for fertilization signals to complete meiosis. The core regulatory factor is the Maturation-Promoting Factor (MPF, Cyclin B-CDK1 complex): MPF activation drives cells into mitosis, and its activity is regulated by reversible phosphorylation via Wee1 (inhibitory kinase) and Cdc25 (activating phosphatase); after fertilization, Calmodulin-Dependent Protein Kinase II (CaMKII) is activated, promoting APC/C complex-mediated Cyclin B degradation to terminate MPF activity and complete meiosis. Research focuses include the periodic regulation of MPF activity, signal mechanisms of meiotic arrest and resumption, specific regulation of chromosome segregation, molecular basis of oocyte polarity establishment, and insights from this model for understanding human germ cell maturation and infertility.
Core key proteins: Maturation-Promoting Factor (MPF: Cyclin B, CDK1), Cdc25 phosphatase (activating CDK1), Wee1 kinase (inhibiting CDK1), APC/C complex (degrading Cyclin B), Calmodulin-Dependent Protein Kinase II (CaMKII, activated after fertilization), Luteinizing Hormone Receptor (LHR, initiating meiotic resumption), Mos kinase (activating the MAPK pathway to maintain MII phase arrest), MAPK (ERK1/2, regulating meiotic progression), cytoskeletal proteins (microtubules, Actin, regulating chromosome segregation and polarity), oocyte-specific proteins (Bub3, Emi2, regulating meiotic checkpoints).