一个在G点中打断细胞循环的因素
Yutaka Sadakane1, Yasuhiro Iwao1
1Biological Institute, Faculty of Science, Yamaguchi University, Yamaguchi 753, Japan.
Development, growth & differentiation
|June 7, 2023
概括
青卵细胞含有特定于G2的细胞静止因子 (G2-CSF),可以阻止细胞循环的进展. 这种在胚芽囊泡和细胞质中发现的因子,在介质停止和G2/M过渡调节中起着关键作用.
科学领域:
- 细胞生物学 细胞生物学
- 发展生物学 发展生物学
- 生殖生物学 生殖生物学
背景情况:
- 成熟的两动物卵细胞在介质前期I时自然停滞.
- 这种停止涉及到一个未知的活动,防止细胞周期的进展超出G2类阶段.
研究的目的:
- 识别和描述导致两动物卵子细胞循环停止的因素.
- 调查这个因素在介质停止和早期胚胎细胞周期中的作用.
主要方法:
- 从Rana rugosa卵子中注射生殖囊泡 (GV) 内容和细胞质到Cynops pyrrhogaster和Bufo japonicus的受精卵中.
- 对注射卵中的细胞周期进展,DNA合成和成熟促进因子 (MPF) 循环的监测.
- 评估外源性MPF对细胞循环重新启动的影响.
- 通过注射的Bufo卵细胞组件来研究孕激素诱导的卵细胞成熟的抑制.
主要成果:
- 注射GV含量或细胞质可以防止受精卵分裂和细胞周期进展.
- 注射卵子显示了核胀与脱凝染色体,但没有MPF循环;DNA合成没有受到影响.
- 外源的MPF注射恢复了细胞周期进展到M阶段和裂变.
- 来自Bufo卵细胞的成分抑制了孕激素诱导的卵细胞成熟.
结论:
- 在青卵细胞的GV和细胞质中存在一种G2特异性细胞静止因子 (G2-CSF),它在G2/M或介质前期I中阻止细胞循环.
- G2-CSF对于生理介质停止至关重要,并调节早期胚胎细胞中的G2/M过渡.
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