人类线粒体中pyruvate载体MPC1和MPC2复合物的结构
Yingyuan Sun1, Yaru Wang2, Zheng Xing3,4
1Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
Nature communications
|July 21, 2025
概括
线粒体中酸盐载体 (MPC) 结构揭示了酸盐如何进入线粒体. 低温电磁显示不同状态的复合物,解释抑制剂如何工作以及突变如何影响运输.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 细胞的新陈代谢
背景情况:
- 线粒体的酸盐载体 (MPC) 对于将糖解与线粒体呼吸联系起来至关重要.
- MPC促进了pyruvate的运输到线粒体中,支持ATP的产生和生物合成.
- 该MPC复合体是MPC1和MPC2子单元的异构体.
研究的目的:
- 为了确定人类MPC1-2复合体的高分辨率结构.
- 阐明酸盐运输和抑制剂结合的机制.
- 了解MPC功能和监管的结构基础.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于解析人类MPC1-2结构.
- 抑制剂结合和基质相互作用的生物化学分析.
- 酵母救援测试用于验证突变的功能后果.
主要成果:
- 在IMS开放和矩阵开放状态下获得人类MPC1-2的冷EM结构.
- 传输通道是由MPC1和MPC2之间的特定的跨膜螺旋相互作用形成的.
- 抑制剂UK5099在矩阵侧结合,稳定矩阵开放形状.
- 在MPC2中的W82F突变将该复合体锁定在IMS开放形状中.
结论:
- 对MPC形状的结构洞察力提供了对pyruvate运输的机械理解.
- 这项研究揭示了MPC抑制剂如何通过稳定特定的结构状态来起作用.
- 突变可以改变MPC构造,影响其在细胞代谢中的作用.
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