格子的不稳定性推动了微管子加上末端尖端的原纤维集群的形成
Weizhi Xue1, Jiangbo Wu1, Tamara Bidone2
1Department of Chemistry, Chicago Center for Theoretical Chemistry, The James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States.
Biophysical journal
|February 15, 2026
概括
微管 (MTs) 在它们的动态加点尖端呈现原纤维 (PF) 集群. 这些由格子不稳定驱动的集群影响MT动态和灾难,提供了洞察图林的结构变异性.
科学领域:
- 生物物理学的生物物理.
- 细胞生物学 细胞生物学
- 计算生物学 计算生物学
背景情况:
- 微管 (MTs) 是重要的细胞骨聚合物,对细胞结构和功能至关重要.
- MT动态,特别是在加值端,对于细胞过程至关重要.
- 在MT加端观察到原纤维 (PF) 集群的形成,但缺乏详细的机制理解.
研究的目的:
- 为了研究原纤维 (PF) 在微管 (MT) 加端尖端的集群形成的动力学和微观机制.
- 阐明格子不稳定性在PF集群行为和MT动态中的作用.
- 为了比较PF集群在GTP和GDP结合的管状态.
主要方法:
- 开发一个高分辨率粗粒度 (CG) 分子动力学 (MD) 模型用于tubulin.
- 对MT网格进行了广泛的CG MD模拟,具有不同的异构聚合物层.
- 对模拟数据进行全面的原子级分析.
主要成果:
- 在放松期间,PF集群在GTP和GDP状态都稳定,由纵向放松和横向相互作用驱动.
- 内在的格子不稳定性热力学驱动PF聚类,在较长的MT中积累.
- 与GTP-MTs相比,GDP-MTs形成了更多的PF集群,表现出更快的放松,并因较弱的横向相互作用而促进MT灾难.
结论:
- 格子的不稳定性在微管力学和PF集群形成中发挥着关键作用.
- 在GTP和GDP状态之间,PF集群稳定性和动态不同,影响MT聚合和灾难.
- 这项研究为MT加端尖端的结构变异性及其动态行为提供了新的见解.
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