葡萄糖皮质体受体功能由Hsp90和Hsp70伴侣循环的协调作用调节
Elaine Kirschke1, Devrishi Goswami2, Daniel Southworth1
1Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
Cell
|June 21, 2014
概括
分子伴侣Hsp70和Hsp90调节葡萄糖皮质体受体 (GR) 功能. Hsp70使GR失活,而Hsp90,与cochaperones一起,恢复其结合结合能力和稳定性.
科学领域:
- 分子陪伴者分子陪伴者
- 蛋白质折叠和稳定性 蛋白质折叠和稳定性
- 细胞信号传输 细胞信号传输
背景情况:
- 葡萄糖皮质体受体 (GR) 需要Hsp90分子伴侣来实现其体内功能.
- 虽然Hsp90在体内对联体结合至关重要,但纯化的apo GR可以在没有Hsp90.0的情况下结合联体.
- 众所周知,hsp70可以促进客户端传输到hsp90.
研究的目的:
- 阐明Hsp70和Hsp90在调节GR功能的作用.
- 研究Hsp70和Hsp90相互作用以控制GR活动的机制.
- 为了了解cochaperones和ATP水解如何影响GR-chaperone复合体.
主要方法:
- 用冷电子显微镜可视化GR:Hsp70:Hsp90:Hop复合体.
- 生物化学测试以评估GR联体结合和蛋白质稳定性.
- 涉及ATP水解和可沙佩龙的研究 (Hop, p23).
主要成果:
- Hsp70部分展开并使GR失活,而Hsp90则逆转了这种失活.
- 完全恢复GR联体结合需要Hsp90 ATP水解和可沙佩龙Hop和p23.
- Hsp90 ATP 水解与 Hsp70 ATP 循环结合,以调节客户端转移.
- 来自Hsp90的释放保护GR免受聚合,并增强连接体亲和力,与Hsp70.0的释放不同.
结论:
- Hsp70和Hsp90之间的协调相互作用对于GR的稳定性和功能至关重要.
- Hsp90的作用是保护GR免受聚合,并增强其结合体结合能力.
- 伴侣ATP循环和辅助伴侣的相互作用为GR活动提供了调节机制.
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