类似液体的冷凝,结合酸,驱动 filaments的聚合和捆绑
Caleb Walker1, Aravind Chandrasekaran2, Daniel Mansour2
1Biomedical Engineering, The University of Texas at Austin, Austin, TX, United States.
bioRxiv : the preprint server for biology
|June 3, 2024
概括
蛋白质凝结物可以捆绑actin丝,而不需要聚合酶活性. 形成凝聚物和结合actin的任何蛋白质都可以通过多价值交叉连接来实现这一目标,组织细胞骨纤维.
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:
- 类似液体的蛋白质凝结物对于细胞功能至关重要.
- 此前,VASP (一种过程性动氨酸聚合酶) 凝聚物被证明可以聚合并捆绑动氨酸纤维,使其变形为棒状结构.
- 在内部凝结表面积聚的光纤使曲率最小化,导致并行光纤束.
研究的目的:
- 为了调查actin聚合酶活性是否对于凝结物介导的actin捆绑至关重要.
- 确定对蛋白质凝聚物的最低要求,以捆绑活性丝.
- 扩大对能够组织细胞骨丝的蛋白质的理解.
主要方法:
- 在由Lamellipodin (一种没有聚合酶活性的活性聚合物) 形成的冷凝物中实验观察了活性丝的行为.
- 基于代理的计算模型的开发,以探讨对凝结物介导的活性捆绑的要求.
- 基因工程创建一个嵌合蛋白 (Eps15与一个actin-binding动机) 测试假设.
主要成果:
- 拉梅利波丁的凝结物,缺乏聚合酶活性,有效聚合并捆绑的活性纤维.
- 计算模型表明,任何一种动氨酸结合凝聚物形成蛋白质的多价值交联可以捆绑纤维.
- 设计的Eps15嵌合体形成了凝结物,有效地驱动了actin聚合和捆绑,验证了假设.
结论:
- 动氨酸聚合酶活性不是蛋白质凝结物捆绑动氨酸纤维的先决条件.
- 任何能够形成凝聚物和结合actin的蛋白质都可以通过多价值交联来组织细胞骨纤维.
- 这扩大了蛋白质的范围,包括非聚合酶的活性蛋白结合剂,可以通过相位分离来调解细胞骨组织.
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