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Updated: Jul 26, 2025

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通过TIM23复合体进口线粒体蛋白质的结构基础

Sue Im Sim1, Yuanyuan Chen1,2, Diane L Lynch3,4

  • 1Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.

Nature
|June 21, 2023
PubMed
概括

这个TIM23复合体将蛋白质导入线粒体. 结构研究显示Tim17,而不是Tim23,形成了蛋白质转移通道,挑战了以前的线粒体蛋白质进口模型.

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Mitochondrial protein import is powered by two distinct energy sources: ATP hydrolysis and electrochemical potential across the inner membrane. Newly synthesized precursors are bound by cytosolic chaperones of the Hsp70 family, which guide them to the import receptors on the mitochondrial surface. Utilizing the energy of ATP hydrolysis, Hsp70 chaperones transfer these precursors to the TOM receptors on the mitochondrial outer membrane.
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