类似液体的冷凝物介导着在动素分支和捆绑之间进行竞争
Kristin Graham1, Aravind Chandrasekaran2, Liping Wang3
1Department of Biomedical Engineering, University of Texas at Austin, Austin, TX 78712.
概括
细胞活性蛋白重塑涉及分支和捆绑之间的竞争. 这项研究表明,多组分蛋白质凝结物可以控制活性蛋白网络的形成,创造细胞运动必不可少的复杂结构.
科学领域:
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
- 生物化学 生物化学
背景情况:
- 动氨酸网络对于细胞运动至关重要,涉及动氨酸分支和捆绑之间的平衡.
- 分支的行为丝之间存在的硬质障碍阻碍了捆绑.
- 以前,分支或捆绑因子的蛋白质凝结物被证明可以促进它们各自的功能.
研究的目的:
- 研究细胞环境中分支和捆绑蛋白质的同时存在如何影响actin网络的形成.
- 为了确定控制蛋白质凝聚物是否促进活性蛋白分支或捆绑的因素.
主要方法:
- 添加分支的动因核子,Arp2/3复合物,对动因捆绑蛋白,VASP的凝结物.
- 在不同的actin与VASP比率下观察actin丝组织.
- 与基于代理的模拟进行比较.
主要成果:
- 在较低的动素与VASP比率下,Arp2/3介导的分支抑制了VASP介导的捆绑.
- 在较高的乙烯与VASP比率下,Arp2/3的添加导致了星形结构,捆绑的纤维从一个分支的核心中出现.
- 这些结构模仿了细胞形成,比如从状状网络中出现的类动物.
结论:
- 多组分,类似液体的蛋白质凝聚物可以动态调节actin分支和捆绑之间的竞争.
- 这些凝结物可以组织与细胞形态和运动相关的更高层次的活性蛋白结构.
- 这些发现为控制细胞骨组织在复杂细胞环境中的机制提供了洞察力.
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