BiP/ERdj3的强度调节的伴侣活性与它们的同类DnaK/DnaJ相反
Souradeep Banerjee1, Debojyoti Chowdhury2, Soham Chakraborty1
1Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana, India.
Protein science : a publication of the Protein Society
|June 12, 2024
概括
与道相关的护卫体BiP和ERdj3在强力下作为机械折叠酶,与细胞质DnaK/DnaJ保持酶不同. 这种依赖力量的行为有助于共同翻译蛋白质折叠和转位.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 细胞力学 细胞力学
背景情况:
- 聚链在细胞转位过程中经历机械张力.
- 分子陪伴者对于折叠这些经历紧张的多来说至关重要.
- 道关联的护卫者和强力加载的多之间的相互作用尚未完全理解.
研究的目的:
- 为了研究道相关的护航者 (BiP,ERdj3) 与细胞质同类物 (DnaK,DnaJ) 的机械护航者活性.
- 确定机械力在调节伴侣功能的作用 (foldase与holdase).
- 探索伴侣活动对协译蛋白折叠的贡献.
主要方法:
- 在不同的机械约束下对BiP/ERdj3和DnaK/DnaJ活动进行比较分析.
- 测量伴侣驱动的折叠过程中产生的机械能量.
- 应变理论的应用来解释陪伴者可变形性和功能.
主要成果:
- 道相关的伴侣BiP/ERdj3在强力下表现出强大的折叠酶活性,而细胞质DnaK/DnaJ则作为保持酶起作用.
- 在没有力量的情况下,BiP/ERdj3过渡到持久性活动,表现出依赖力量的行为.
- 伴侣介导的折叠产生了多达54 zJ的机械能量,可能有助于蛋白质转位.
结论:
- 伴奏子活动是机械调节的,与道相关的伴奏子作为折叠酶和细胞质的伴奏子作为保持酶.
- 较高的内在变形性与折酶活性相关 (BiP,ERdj3),而较低的变形性表明酶功能 (DnaK,DnaJ).
- 这项研究为共同翻译性蛋白质折叠提供了一个新的视角,突出了机械力量在调节伴侣功能中的作用.
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