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线粒体应激通过OMA1-DELE1-HRI通路传递给细胞质
Xiaoyan Guo1,2, Giovanni Aviles1,2, Yi Liu3
1Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, CA, USA.
Nature
|March 6, 2020
概括
线粒体应激激活了OMA1-DELE1-HRI通路,通过eIF2α酸化传递信号来诱导ATF4. 这一途径对于哺乳动物细胞的综合应激反应至关重要.
科学领域:
- 细胞生物学
- 应激反应的分子机制
背景情况:
- 线粒体功能障碍激活了哺乳动物细胞的综合应激反应 (ISR).
- 在ISR过程中,真核转化启动因子2α (eIF2α) 的酸化导致ATF4的诱导.
- 传递线粒体应激到ATF4的精确机制仍然难以捉摸.
研究的目的:
- 确定传递线粒体应激到ATF4诱导的信号通路.
- 阐明HRI,OMA1和DELE1在这种应激反应途径中的作用.
主要方法:
- 基因组范围的CRISPR干扰选以确定上游因素.
- 研究蛋白相互作用和激酶活性的生物化学测试.
- 对ATF4转化和综合应激反应激活的分析.
主要成果:
- HRI (血液调节抑制剂) 被确定为传递线粒体压力的基本eIF2α激酶.
- OMA1 (一种蛋白酶) 和DELE1 (一种线粒体蛋白质) 在HRI上游发挥作用.
- 线粒体应激触发了OMA1依赖的DELE1裂变,导致细胞质DELE1积累和HRI激活.
- 在eIF2α酸化下游的ATF4转化中,DELE1是必不可少的.
- 抑制OMA1-DELE1-HRI通路会引起另一种伴奏反应.
结论:
- OMA1-DELE1-HRI通路是线粒体应激到ATF4的主要中继.
- 在与线粒体功能障碍相关的疾病中,这种途径代表了调节ISR的潜在治疗标.
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