H+运输是线粒体ADP/ATP载体的一个组成功能
Ambre M Bertholet1, Edward T Chouchani2, Lawrence Kazak2
1Department of Physiology, University of California San Francisco, San Francisco, CA, USA.
Nature
|July 26, 2019
概括
线粒体ADP/ATP载体 (AAC) 调解ATP/ADP交换和质子运输. 这种双重功能将能量生产和热生成联系在一起,由细胞ATP需求动态控制.
科学领域:
- 线粒体生物学
- 生物能源
- 膜运输
背景情况:
- 线粒体ADP/ATP载体 (AAC) 通过交换线粒体ATP与细胞质ADP,对细胞的ATP产生至关重要.
- 在线粒体脱中AAC的潜在作用已被提出,但在机制上尚不清楚.
研究的目的:
- 从小鼠的线粒体内膜直接记录AAC电流.
- 确定和描述AAC的不同运输方式.
- 阐明AAC介导的线粒体解的机制.
主要方法:
- 从隔离的内线粒体膜中直接记录AAC电流.
- 在各种小鼠组织中研究AAC传输.
- 分析自由脂肪酸对AAC功能的影响.
主要成果:
- 确定了AAC的两个不同的运输方式:ADP/ATP交换和H+运输.
- AAC介导的H+流需要自由脂肪酸,类似于UCP1介导的H+泄漏.
- ADP/ATP交换可以负面调节,但不能消除H+泄漏.
结论:
- AAC通过合 (ATP生产) 和未合 (热生成) 的能量转换进行调解.
- AAC的双运输模式允许通过细胞ATP需求动态控制线粒体解.
- 通过其双重传输功能,AAC连接了细胞能量生产和热量产生.
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