SMC5/6 通过对COP9信号的负调节促进复制叉稳定性
Michelle J Xu1, Philip W Jordan1,2
1Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.
International journal of molecular sciences
|January 23, 2024
概括
在小鼠细胞中,SMC5/6复合体对于重新启动停滞不前的DNA复制分叉至关重要. 失去SMC5/6会导致叉子不稳定,因为它会影响叉子保护因子和MRE11活动.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
背景情况:
- 在细胞增殖过程中,DNA复制叉停滞是一个常见的事件.
- 众所周知,SMC5/6综合体能够保持复制叉的完整性.
- 在哺乳动物DNA复制中SMC5/6的确切作用尚不清楚.
研究的目的:
- 研究SMC5/6复合体在哺乳动物细胞中维持复制叉完整性的分子机制.
- 为了阐明SMC5/6在复制分叉在停机后重新启动中的作用.
- 了解SMC5/6损失如何影响叉子保护和MRE11活动.
主要方法:
- 在小鼠胚胎干细胞 (mESCs) 中利用辅酶诱导性降解 (AID) 系统,对小鼠胚胎干细胞 (SMC5) 的急性和可逆性耗尽.
- 采用了DNA纤维技术,小分子抑制试验和免疫光显微镜.
- 研究了SMC5/6,COP9信号体 (CSN) 和叉子保护因子之间的相互作用.
主要成果:
- SMC5 耗尽导致复制叉重新启动有缺陷.
- 在SMC5-贫乏细胞中观察到过度的MRE11介导切除和分叉保护因子的乱局部.
- SMC5/6对COP9信号体 (CSN) 进行负调节,以促进分叉保护因子的局部化.
结论:
- 在哺乳动物细胞中,SMC5/6对于有效的复制叉重新启动至关重要.
- SMC5/6 调节 CSN 活动,以确保分叉保护因子的适当定位.
- 这个SMC5/6的规则对于稳定复制叉和在停机缓解后重新启动至关重要.
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