Study on the female specific regulation of meiosis

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K19315
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 44:Biology at cellular to organismal levels, and related fields
• Research Institution: Kumamoto University
• Principal Investigator: Ishiguro Kei-ichiro 熊本大学, 発生医学研究所, 教授 (30508114)
• Project Period (FY): 2022-06-30 – 2024-03-31
• Keywords: 減数分裂 / 卵子 / 不妊

Outline of Final Research Achievements

In this study, we examined gene expression in female oocytes at the onset of meiosis using scRNA-seq analysis. Mutant Stra8 mice, in which Stra8-RB interaction is lost, were generated. Mutant Stra8-expressing mice showed a delay in progression to meiosis due to loss of interaction with RBs. Furthermore, the ovaries of mutant Stra8 mice showed an early reduction in the number of primordial follicles immediately after birth, indicating that the oocytes were unable to maintain the dormant state and were eliminated around birth. Thus, it is suggested that the interaction between STAR8 and RB acts in female-specific meiosis initiation, and that the delay at the onset of meiosis also affects later oocyte development.

Free Research Field

発生生物学

Academic Significance and Societal Importance of the Research Achievements

ヒトに見られる不妊症は原因が不明とされる症例が多いことが知られている。女性の場合、妊娠中の母親の母体内で胎児の時期に、減数分裂が開始された生殖細胞の数によって、将来大人になったときの卵子の貯蔵数が決定される。すなわち、女性は生まれる前には、減数分裂が開始されて生涯にわたる卵子が準備されていることになる。本研究は、原発性卵巣不全や早発性閉経など卵子の形成不全や早期枯渇を示す不妊症の病態の解明に資することが期待される。また妊娠期に癌抑制タンパク質RBに影響を与える可能性のある投薬や、創薬での指針となる可能性がある。