Hsp90-Hsp70-Hop-GR的结构显示了Hsp90客户端加载机制
Ray Yu-Ruei Wang1, Chari M Noddings1, Elaine Kirschke1
1Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA.
Nature
|December 23, 2021
概括
这项研究揭示了分子辅助剂Hsp70和Hsp90与cochaperone Hop如何加载和禁用葡萄皮质受体 (GR) 的分子机制. 这些发现提供了对伴侣介导的客户端蛋白重塑的完整理解.
科学领域:
- 分子生物学
- 结构生物学
- 生物化学
背景情况:
- 维持蛋白质的健康对于生物的生存至关重要.
- 分子伴侣热冲击蛋白90 (Hsp90) 和热冲击蛋白70 (Hsp70) 对于客户蛋白的折叠和成熟至关重要.
- 葡萄皮质受体 (GR) 是一个关键的客户蛋白质,依赖于Hsp90和Hsp70.
研究的目的:
- 阐明 Hsp90-Hsp70-Hop 陪伴机械在客户端蛋白质加载和无活化的分子机制.
- 确定GR负载复合体的冷电子显微镜结构.
主要方法:
- 用冷电子显微镜 (cryo-EM) 确定GR负载复合物的结构.
- 结构分析以了解GR,Hsp90,Hsp70和Hop之间的相互作用.
主要成果:
- GR加载复合体的冷EM结构揭示了Hsp70如何将GR传递给Hsp90.
- 其中包括两种Hsp70蛋白:一种提供GR,另一种提供Hop.
- 在由Hsp90,Hsp70和Hop形成的延伸结合口袋中,GR被识别为部分展开的状态,解释其无活化.
结论:
- 这项研究介绍了从加载到激活的伴侣依赖客户端蛋白重塑的完整分子机制.
- 这些发现确立了分子伴侣对客户端识别,抑制,转移和激活的一般原则.
- 研究提供了前所未有的分子洞察力,
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