脂质信号驱动由YME1L进行线粒体的蛋白质分解
Thomas MacVicar1, Yohsuke Ohba1, Hendrik Nolte1,2
1Max-Planck-Institute for Biology of Ageing, Cologne, Germany.
Nature
|November 8, 2019
概括
在细胞压力如缺氧期间,i-AAA蛋白酶YME1L重新连接线粒. 这一过程涉及mTORC1-LIPIN1-YME1L轴,支持癌细胞生长,并在胰腺瘤中观察到.
科学领域:
- 细胞生物学
- 线粒体动力学
- 代谢调节
背景情况:
- 线粒体重编程对于细胞适应压力和发育至关重要.
- 细胞代谢和线粒体功能之间的相互作用是细胞生存和疾病的关键.
- 了解线粒体蛋白质稳定对于治疗代谢障碍和癌症至关重要.
研究的目的:
- 研究i-AAA蛋白酶YME1L在线粒体应激适应中的作用.
- 阐明YME1L调节线粒体蛋白质的分子机制.
- 确定YME1L介导的线粒体变化对胰腺管腺癌 (PDAC) 进展的相关性.
主要方法:
- 研究了因缺氧和营养缺乏而导致的线粒体蛋白质重新连接.
- 使用了mTORC1和YME1L的遗传和药理抑制.
- 分析了涉及LIPIN1的脂质信号通路.
- 评估YME1L对线粒体蛋白质降解和细胞生长的影响.
- 在PDAC球体和异种移植中检查了YME1L介导的线粒体重塑.
- 分析了人体PDAC瘤组织中的线粒体蛋白质组变化.
主要成果:
- 在压力条件下,YME1L会降解线粒体蛋白质,包括转位蛋白,脂质转移蛋白和代谢酶.
- 抑制mTORC1通过LIPIN1触发脂质信号级联,降低酸乙醇胺并促进YME1L依赖的蛋白解.
- 通过YME1L介导的线粒体重塑限制了线粒体生物发生,并在压力期间支持细胞生长.
- 在体外和体内,YME1L活动促进PDAC细胞的生长.
- 在人类PDAC组织中观察到类似的线粒体蛋白质组变化.
结论:
- mTORC1-LIPIN1-YME1L轴被确定为线粒体蛋白质稳定的一个关键调节器.
- 这个轴在代谢和线粒体动态的界面上起作用,控制线粒体重塑.
- 由YME1L驱动的线粒体变化对PDAC细胞存活和瘤生长至关重要,突出显示其作为治疗点的潜力.
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