作为机械敏感受体的破裂的行为丝
Vilmos Zsolnay1, Margaret L Gardel2, David R Kovar3
1Graduate Program in Biophysical Sciences, University of Chicago, Chicago, Illinois.
Biophysical journal
|June 19, 2024
概括
机械应变会导致活性丝形成一个转移稳定的破裂状态,揭示新的结合点. 这种裂形成被LIM-域蛋白识别,增强在机械应力下丝的稳定性.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 细胞力学 细胞力学
背景情况:
- 动蛋白丝网对机械刺激做出反应.
- 压力引起的actin结构和蛋白质相互作用的变化尚未完全理解.
- 众所周知,动氨酸结合蛋白的活性是由线索菌株调节的.
研究的目的:
- 为了研究拉伸应变对乙烯丝结构的分子水平影响.
- 为了确定机械应变如何改变actin线程构造和暴露结合点.
- 为了探索actin结合蛋白与紧张的actin纤维的相互作用.
主要方法:
- 所有原子的分子动力学模拟,以施加拉伸应变到actin丝.
- 在应力下分析actin子单元的组织和子单元之间的连接.
- 蛋白质与蛋白质对接模拟,以确定应变性动蛋白的结合伙伴.
主要成果:
- 在完好无损的,紧张的丝中,actin子单元组织的最小变化.
- 由应变引起的形状变化会产生一个变态稳定的破裂的烯酸丝状状态.
- 破裂的接口暴露了LIM域蛋白识别的结合点.
- LIM 域稳定了这些受损的活性纤维.
结论:
- 应变会诱导在动氨酸纤维中形成一个转移稳定的裂变形状,与完整的结构不同.
- 这种裂作为特定的活性调节蛋白的强力激活结合点,例如LIM域.
- 与LIM域的相互作用增强了机械损坏的活性纤维的稳定性,提出了一个新的机械敏感结合模型.
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