VDAC2 抑制了 BAK 的激活和线粒体亡
Emily H Y Cheng1, Tatiana V Sheiko, Jill K Fisher
1Howard Hughes Medical Institute, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
概括
线粒体外膜蛋白VDAC2在不活跃状态下封存了BAK的前细胞蛋白. 取代VDAC2激活BAK,启动细胞亡,揭示了编程细胞死亡的关键调节者.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 线粒体中亡的途径是由亲亡蛋白BAK和BAX启动的.
- 细胞维持BAK在线粒体中处于非活性单体状态的机制目前尚不清楚.
研究的目的:
- 阐明调节线粒体中BAK无活性构成的机制.
- 识别与BAK活性相互作用并控制的蛋白质.
主要方法:
- 同免疫沉测试用于识别BAK相互作用蛋白.
- 在VDAC2缺乏细胞中分析BAK寡合化和亡敏感性.
- 对VDAC2的过度表达研究,以评估其对BAK激活和亡的影响.
主要成果:
- 发现BAK与VDAC2复合在一起,这是一个低丰富的线粒体外膜蛋白质,在可活细胞中.
- 特别是VDAC2与BAK.的非活性构成相互作用.
- 缺乏VDAC2的细胞表现出增加的BAK寡合化和亡易感性,与缺乏VDAC1的细胞不同.
- 过度表达VDAC2抑制了BAK激活和线粒体亡途径.
结论:
- VDAC2充当BAK活动的关键调节者,使其保持不活跃状态.
- 亡的激活涉及BH3-only蛋白质从BAK中取代VDAC2,导致BAK的同类寡合化.
- VDAC2提供了线粒体功能和核心亡机器之间的联系.
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