在压力下,蛋白质酶组合的伴侣翻译需要在等离子膜的Ede1相分离
Thomas D Williams1, Aurellia Winaya1, Ifeoluwapo Joshua1
1MRC-PPU, School of Life Sciences, University of Dundee, Dow Street, Dundee DD5 1EH, UK.
iScience
|January 18, 2024
概括
细胞应激反应涉及蛋白质酶组合的增加. 蛋白质Ede1通过相分离招募特定的mRNA进行翻译,这对于在压力期间的生存至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 应激反应机制 应激反应机制
背景情况:
- 细胞蛋白质组适应对于在压力条件下生存至关重要.
- 增加蛋白质酶组合伴侣 (PAC) 的翻译增强了蛋白质酶组合和细胞降解能力.
- 内细胞蛋白Ede1在招募PAC mRNA到皮质动蛋白补丁中发挥作用,以便在Saccharomyces cerevisiae中的压力期间进行翻译.
研究的目的:
- 阐明Ede1在细胞应激时调解PAC mRNA转化增加的机制.
- 研究Ede1的相分离能力在调节蛋白质酶组合和细胞存活中的作用.
主要方法:
- 涉及域名交换的遗传研究在Ede1.
- 药理疗法用于诱导细胞应激.
- 对PAC mRNA翻译和蛋白质酶组合的分析.
主要成果:
- 在压力下调解PAC mRNA招募和翻译时,Ede1的分相能力至关重要.
- 将Ede1的相分离域替换为与非相关蛋白质的相分离域,维持了PAC的表达.
- 失去Ede1的相隔区域,消除了压力诱导的PAC表达,损害了蛋白酶组合,导致细胞死亡.
结论:
- 在细胞应激过程中,Ede1利用相分离来增强特定mRNA的翻译,如PACs.
- 这种机制确保在最需要的时候增加了蛋白酶组合和降解能力.
- 通过选择性地促进必不可少的应激反应基因的翻译,Ede1介导的相分离提供了关键的生存优势.
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