凝聚素的DNA出口门与其入口门不同,并通过乙化来调节
Kok-Lung Chan1, Maurici B Roig, Bin Hu
1University of Oxford, Department of Biochemistry, South Parks Road, Oxford OX1 3QU, UK.
Cell
|August 21, 2012
概括
姐妹染色体凝聚力依赖于凝聚复合体. 影响Wapl亚单元活动的突变减少了凝聚蛋白的循环,并揭示了染色体解离的释放机制,影响了DNA复制和细胞分裂.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 姐妹染色体凝聚力对于细胞分裂期间精确的染色体分离至关重要.
- 凝聚体复合体,包括Smc1,Smc3和α-kleisin,建立和保持凝聚力.
- Eco1乙化Smc3,抵消Wapl的抑制活性,这对于凝聚力的建立至关重要.
研究的目的:
- 调查Wapl子单位活动在凝聚力营业额和凝聚力建立中的作用.
- 阐明凝聚素与染色质分离的机制.
- 探索凝聚环开放和Smc3乙化的功能影响.
主要方法:
- 局部定向的突变发生法,以废除Wapl的反体制活动.
- 在周心色素上对凝聚素周转率的分析.
- 通过将Smc3的核酸结合域与α-kleisin的N终端域融合而进行蛋白质工程.
主要成果:
- 降低Wapl抗建立活性的突变也降低了围心色素上的凝聚蛋白周转率.
- 发现了一种新型的"释放"活动,固有于Wapl相关的凝聚体复合体,促进了与染色体的分离.
- 融合结构减少了凝聚力周转,并在没有Eco1的情况下实现了Wapl独立的凝聚力建立.
结论:
- 凝聚素解离涉及"释放"活动,打开Smc3/α-kleisin接口,创建一个DNA退出门.
- Smc3的乙化可能会防止与α-kleisin的解离,从而稳定凝聚力.
- 凝聚环的调节开放是控制染色体结合和分离的关键机制.
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