客户端结合的替代模式使Hsp70具有功能性可塑性
Alireza Mashaghi1, Sergey Bezrukavnikov1, David P Minde1
1FOM institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
Nature
|November 4, 2016
概括
在不同折叠阶段稳定蛋白质,而不仅仅是未折叠的链. 这种由其盖子和槽调节的伴奏活动会影响蛋白质折叠和聚合.
科学领域:
- 分子生物学
- 生物化学
- 蛋白质动力学
背景情况:
- 热冲击蛋白70 (Hsp70) 对于蛋白质平衡至关重要,有助于折叠,防止聚合,并调节蛋白质的流通.
- 据信Hsp70通过被ATP驱动的盖子覆盖的结槽与基质相互作用.
- 直接观察不同折叠状态的Hsp70基质相互作用和理解盖子的动态是具有挑战性的.
研究的目的:
- 研究Hsp70 (DnaK) 与各种构成状态中的蛋白质基质的相互作用机制.
- 阐明Hsp70盖和槽在基板结合和稳定中的作用.
- 探索各种Hsp70结合方式对蛋白质折叠和聚合的影响.
主要方法:
- 使用光学子直接测量细菌Hsp70同类物 (DnaK) 和蛋白质基质之间的力量和相互作用.
- 通过DnaK研究未折叠,部分折叠和近原生蛋白质结构的结合和稳定.
- 通过使用截断的盖子和突变的槽变体,研究了DnaK盖子和槽的协同作用.
主要成果:
- DnaK不仅可以结合和稳定未折叠的多链,还可以结合和稳定部分折叠和近原生蛋白质结构.
- Hsp70的盖子和槽功能协同稳定折叠结构;盖子的切断或槽的突变显著损害了这一功能.
- Hsp70在蛋白质稳定和不稳定中表现出核酸调节的双重作用,通过保护各种蛋白质适配体,影响晚期折叠和抑制聚合.
结论:
- 扩展了Hsp70功能的正规模型,包括与折叠蛋白状态的相互作用和稳定.
- Hsp70在多个折叠阶段调节蛋白质结构的能力对蛋白质折叠,细胞蛋白质稳定和疾病有重大影响.
- 这些发现突显了Hsp70在通过多种基质相互作用机制维持细胞蛋白质平衡方面的多功能性.
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