线粒体Hsp60的不对称的顶端域状态协调了基质的参与和Chaperonin组件的组合
Julian R Braxton1,2,3, Hao Shao2, Eric Tse2
1Graduate Program in Chemistry and Chemical Biology, University of California San Francisco, San Francisco, CA, USA.
Nature structural & molecular biology
|July 1, 2024
概括
线粒体热冲击蛋白60 (mtHsp60) 和mtHsp10有助于线粒体中的蛋白质折叠. 化EM结构揭示了mtHsp60是如何形成的.
科学领域:
- 线粒体生物学 线粒体生物学
- 蛋白质折叠过程中的蛋白质折叠
- 结构生物学是结构生物学.
背景情况:
- 线粒体热冲击蛋白60 (mtHsp60) 对于线粒体蛋白质稳定至关重要,它与它的共同伴侣mtHsp10一起折叠蛋白质.
- mtHsp60依赖ATP的折叠周期的结构细节尚不清楚.
研究的目的:
- 阐明在依赖ATP的蛋白质折叠过程中线粒体沙佩罗宁系统的结构机制.
- 调查 mtHsp60 角域在客户互动和折叠进展中的作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 确定了一个超稳定的人类mtHsp60 V72I突变的结构.
- 在 chaperonin 综合体内的三个不同的状态中分析客户密度.
主要成果:
- 识别了客户端与mtHsp60顶端域和C端的交互,协调客户端的定位.
- 揭示了mtHsp60的不对称ATP结合状态,其中的顶端域促进mtHsp10和客户端结合.
- 在mtHsp60-10复合体内观察到完整的客户端封装,接触表明蛋白质成熟.
结论:
- mtHsp60的顶端域在客户端捕获和通过陪伴者循环的进展中发挥着独特的作用.
- 这些发现支持了线粒体蛋白质折叠中I组Chaperonin功能的保存机制.
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