比德,巴克斯和脂质合作,在线粒体外膜中形成超分子开口
Tomomi Kuwana1, Mason R Mackey, Guy Perkins
1La Jolla Institute for Allergy and Immunology, 10355 Science Center Drive, San Diego, CA 92121, USA.
Cell
|November 7, 2002
概括
Bcl-2家族蛋白质在线粒体外膜中产生开口,允许在亡过程中释放大量蛋白质. 这一过程涉及BH3/Bax/脂质相互作用,并被Bcl-x(L) 阻断.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- Bcl-2家族蛋白质是细胞亡的关键调节者.
- 线粒体外膜通透性 (MOMP) 是亡的关键阶段,导致亲亡因素的释放.
- 对于MOMP的精确机制和大型蛋白质的转位仍然不完全理解.
研究的目的:
- 阐明Bcl-2家族蛋白质对外线粒体膜透的分子机制.
- 为了确定巴克斯介导膜开放所需的最小组件.
- 研究特定脂质和调控蛋白在这个过程中的作用.
主要方法:
- 利用无细胞系统研究蛋白质-脂质相互作用.
- 从定义的分子中使用囊泡复合来模仿线粒体外膜.
- 评估了使用大型德克斯分子 (2兆达尔顿) 来测量孔径大小的膜透性.
主要成果:
- 由Bcl-2蛋白质进行的外膜透不需要线粒体矩阵,内膜或其他细胞蛋白质.
- 比德或其BH3域激活了单体Bax,形成了膜开口,足以进行2兆的德克斯通道.
- 卡迪奥利平对于这个过程是必不可少的,而抗亡的Bcl-x(L) 抑制了巴克斯激活和膜透.
结论:
- 在亡过程中,线粒体蛋白质的释放是由线粒体外膜中的超分子开口介导的.
- 这些开口是由BH3域,巴克斯和心脏脂蛋白的相互作用促进的.
- 抗亡蛋白Bcl-x(L) 直接抑制了这种巴克斯介导的透过程.
相关概念视频
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