蛋白质错误折叠释放人类HSF1从HSP70延迟控制中释放出来
Michela Ciccarelli1, Claes Andréasson1
1Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, S-10691 Stockholm, Sweden.
Journal of molecular biology
|August 9, 2024
概括
热冲击因子1 (HSF1) 是由HSP70护送人来调节的. 错误折叠的蛋白质破坏了这种相互作用,激活HSF1和热冲击反应以保持细胞健康.
科学领域:
- 分子生物学分子生物学
- 细胞应激反应的应激反应
背景情况:
- 热冲击因子1 (HSF1) 控制热冲击反应 (HSR),对蛋白质稳定至关重要.
- HSF1的调节对人类健康至关重要,但尚未完全理解.
- HSP70伴侣被认为是HSF1.1的负调节者.
研究的目的:
- 研究HSP70和错误折叠蛋白在人类HSF1延迟和激活中的作用.
- 通过HSP70.0.阐明HSF1调节的机制.
主要方法:
- 净化和分析HSF1-HSP70复合物.
- 在HEK293T细胞中进行特定位置的UV光交联.
- 在各种压力条件下监测HSF1-HSP70相互作用.
主要成果:
- 纯化HSF1-HSP70复合体显示基底DNA结合被HSP70.0抑制.
- 错误折叠的蛋白质逆转了HSF1.1的HSP70介导抑制.
- 在热冲击或蛋白质错折诱导时,HSF1与HSP70分离.
- 在未应力细胞中,HSF1与HSP70的基质结合域结合.
结论:
- 潜伏的HSF1与HSP70.0形成动态复合体.
- 错误折叠的蛋白质竞争HSP70结合,定位可用的伴侣.
- 通过压力激活人类的HSF1是由HSP70可用性介导的.
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