微观相互作用控制微管和分子电机的活性混合物的结构转变
Bibi Najma1, Wei-Shao Wei1, Aparna Baskaran1
1Department of Physics, Brandeis University, Waltham, MA 02453.
概括
运动蛋白质动力学决定了微管组织,将活性凝从伸展束转变为收缩星. 这种自我组装模型揭示了微观相互作用如何控制大规模细胞骨材料的行为.
科学领域:
- 生物物理学的生物物理.
- 软物质物理学 软物质物理学
- 细胞生物学 细胞生物学
背景情况:
- 微管和分子电机对于细胞功能至关重要,例如染色体分离和运输.
- 重建的细胞骨系统作为活性物质自我组织的模型,表现出复杂的动态.
- 控制这些系统中收缩性和伸展性行为之间的切换的因素仍然不太清楚.
研究的目的:
- 在一个最小的重建的微管电机系统中,研究从伸展束转向收缩星的起源.
- 阐明蛋白质-蛋白质相互作用动力学如何影响活性细胞骨材料的新兴性质.
主要方法:
- 使用了复制的系统与稳定微管,耗尽剂,腺5'-三酸盐 (ATP) 和kinesin-1电机集群.
- 分析了电机集群的微管结合和解结合动力学,以了解末端积累动态.
- 开发了一个自组装模型,结合了阴性和极性对齐相互作用,以捕捉伸展到收缩的过渡.
主要成果:
- 电机集群动力学,特别是它们的末端积累能力,驱动微管极性分类和星体形成.
- 运动末端积累的微观时间尺度决定了恒星形成的宏观时间尺度.
- 仅仅是生物化学调节是不够的;通用对齐相互作用也会影响捆绑形成,即使在末端积累电机.
结论:
- 从伸展束转变为收缩天体的转变是由对齐相互作用和电机驱动的末端积累之间的竞争决定的.
- 一个单一的控制参数,即成分度的比率,决定了材料规模的组织.
- 微观的生化和机械调整协调了活跃的细胞骨材料的强大的自我组织.
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