GroEL作用的机制:在GroES下从隔离位置有效释放聚
J S Weissman1, C M Hohl, O Kovalenko
1Department of Genetics, Yale School of Medicine New Haven, Connecticut 06510, USA.
Cell
|November 17, 1995
概括
监护人GroEL-GroES系统通过两步机制协助蛋白质折叠. GroES封存蛋白质,ATP水解驱动它们的释放和生产折叠.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 蛋白质折叠 蛋白质的折叠
背景情况:
- 沙佩罗宁GroEL与沙佩罗宁GroES和ATP一起,在体内促进蛋白质折叠.
- GroEL是一种双环结构;GroES与一个GroEL环不对称地结合.
研究的目的:
- 为了阐明GroEL-GroES介导的蛋白质折叠的机制.
- 为了研究GroEL复合体内的聚结合和释放动态.
主要方法:
- 交叉链接研究以确定聚结合点.
- 单个周转实验使用甲氨酸转糖胺酶.
- 分析GroEL-GroES复合物的形成和解离.
主要成果:
- 聚结合发生在GroEL环上,而不是由GroES (跨复合体) 占据.
- 释放的GroES可以重新结合含有多的GroEL环 (cis复合物).
- 聚酸在cis复合物中受到ADP的保护,并从cis复合物中有效释放,而不是trans复合物.
结论:
- 为GroEL介导的折叠提出了一个两步机制.
- 步骤1:GroES在GroEL腔内取代和隔离聚.
- 步骤2:ATP水解触发GroES释放和生产性多释放.
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