应激诱导蛋白1 (Sti1/Stip1/Hop) 在应激过程中将错误折叠的蛋白质隔离起来
Benjamin S Rutledge1, Young J Kim2, Donovan W McDonald2
1Department of Biochemistry, The University of Western Ontario, London, Canada.
The FEBS journal
|December 31, 2024
概括
应激诱导蛋白1 (Sti1) 在细胞应激期间将错误折叠的蛋白质绑定起来,独立于Hsp90调节而起作用. 蛋白质稳定中的这一关键作用可以防止有毒蛋白质的积累,并有助于细胞恢复.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白质平衡是蛋白质的平衡.
背景情况:
- 应激诱导蛋白1 (Sti1) 和Hsp90ATPase蛋白1 (Aha1) 的激活剂等辅助蛋白对细胞蛋白质质量控制至关重要.
- 这些辅助蛋白与热冲击蛋白Hsp70和Hsp90合作,维持蛋白质折叠并防止错误折叠的蛋白质聚合.
研究的目的:
- 研究Sti1和Aha1在细胞蛋白质稳定中的作用.
- 阐明Sti1在Hsp90介导蛋白质折叠和质量控制中的功能.
主要方法:
- 酵母和哺乳动物细胞模型的分析,Sti1和Aha1表达变化.
- 研究STI1删除对蛋白质聚合和热冲击反应的影响.
- 在蛋白质静止应激过程中对Sti1局部的显微镜检查.
主要成果:
- 失衡的Sti1和Aha1表达导致酵母和哺乳动物细胞的显著生长缺陷.
- 删除STI1会导致错误折叠,无处不在的蛋白质的积累,并增加热冲击反应.
- 在蛋白质静止应激过程中,Sti1形成细胞质内含物,与错误折叠的蛋白质共同定位.
结论:
- 在压力期间,Sti1通过隔离错误折叠的蛋白质来维持蛋白质静止起着至关重要的作用.
- 这种Sti1的功能独立于其先前已知的Hsp90 ATPase调节活动.
- Sti1是细胞防御蛋白质毒性压力的关键组成部分.
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