在卵细胞中,在激素诱导的肌肉成熟过程中,出现诱导卵细胞的活动
1Zoological Institute, Faculty of Science, Hokkaido University, Sapporo, 060, Japan.
Development, growth & differentiation
|June 7, 2023
概括
在卵细胞中形成精子原核需要生殖囊泡材料,并通过蛋白质合成在激素治疗后10-14小时之间发展. 这种前核诱导活性 (PIA) 对于精子在成熟后期的激活至关重要.
科学领域:
- 发展生物学 发展生物学
- 细胞生物学 细胞生物学
- 生殖生物学 生殖生物学
背景情况:
- 卵细胞的荷尔蒙成熟对于启动胚胎发育至关重要.
- 精子需要特定的卵细胞因子来形成前核并激活卵子.
- 前核诱导活性 (PIA) 发展的确切时间和机制尚不清楚.
研究的目的:
- 为了确定卵细胞成熟期间的前核诱导活性 (PIA) 的发育时间表和分子基础.
- 研究胚芽囊泡 (GV) 材料和蛋白质合成在PIA发展中的作用.
- 了解DNA合成和PIA获取之间的关系.
主要方法:
- 用洗剂预处理的青精子注射到不同成熟阶段的卵细胞中.
- 在特定的时间点进行卵子细胞的排卵,然后再注射GV和注射精子.
- 在卵细胞成熟期间用环胺和α-amanitin治疗,以评估蛋白质合成和转录活性.
- 在体外评估卵子提取物中的DNA合成活性.
主要成果:
- 只有当GV在激素治疗 (PHT) 后14小时之前存在时,才能诱导精子前核的形成.
- 在PHT10-14小时之间通过循环赫西米德治疗抑制了PIA,这表明需要蛋白质合成.
- α-阿米尼丁治疗没有影响PIA,这表明转录没有直接参与.
- 在收购PIA之前,DNA合成活动的增加发生了.
结论:
- 前核诱导活性 (PIA) 在10-14小时PHT之间通过转化事件与生殖囊泡物质结合发展.
- 在晚期的成熟阶段,PIA处于静止状态,在18小时PHT时开始对精子激活起作用.
- PIA的发展是独立于de novoRNA合成,但依赖于蛋白质合成.
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