在没有新生组合的情况下,中粒体特异性核细胞在老化的小鼠卵细胞中持续存在
Arunika Das1, Katelyn G Boese2, Kikue Tachibana3
1Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
Current biology : CB
|August 15, 2023
概括
在雌性哺乳动物中,中间体标识是长期维持的,独立于在延长的卵细胞停止期间的新组装. 这一发现挑战了已建立的表观遗传遗传模型.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 细胞生物学 细胞生物学
- 发展生物学 发展生物学
背景情况:
- 中介质对遗传遗传至关重要,但由CENP-A在表观遗传上定义.
- 已建立的模型表明,通过细胞循环合复制和G1组装来维持CENP-A.
- 哺乳动物雌性生殖系的扩展性预相I停止对这个模型提出了挑战.
研究的目的:
- 研究哺乳动物卵细胞中在延长细胞循环停止期间中介质维持的机制.
- 为了测试假设,新的CENP-A组件是需要在前期I停止中心质基因遗传期间.
主要方法:
- 开发一种针对卵细胞的条件淘汰 (cKO) 鼠标模型,用于Mis18α,这是CENP-A组装的一个重要因素.
- 分析来自Mis18α淘汰赛小鼠的卵细胞中CENP-A核细胞组合.
- 在老年雌性小鼠中评估中心体CENP-A的丰度和生育能力.
主要成果:
- 来自Mis18α淘汰排卵细胞的胚胎在胚胎基因组激活之前未能组装CENP-A核体.
- 在雌性生殖系中删除Mis18α甚至在衰老6-8个月后也不会影响中心体CENP-A水平.
- 在Mis18α淘汰赛小鼠中没有观察到对生育能力的显著影响.
结论:
- 在延长的 I 预相停滞期间,在哺乳动物卵细胞中长期保持着中心染色素.
- 这种维护在逮捕期间独立于新的CENP-A组装.
- 这些发现需要对女性生殖系中中心粒体身份传播的既定范式进行修订.
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