活性生物聚合物网络的无动力收缩性
Sihan Chen1,2, Tomer Markovich2,3,4, Fred C MacKintosh1,2,5,6
1Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA.
Physical review. E
|November 18, 2023
概括
这项研究引入了生物聚合物网络中细胞收缩的新型无运动机制. 它解释了活跃的交叉连接器动力学和聚合物特性如何在没有分子电机的情况下驱动收缩.
科学领域:
- 生物物理学的生物物理.
- 细胞力学 细胞力学
- 软物质物理学 软物质物理学
背景情况:
- 细胞收缩性通常依赖于分子电机,如肌肉素,需要极地基质.
- 最近的实验表明,存在运动独立的收缩性,挑战了既有模型.
研究的目的:
- 提出和研究一种强大的,无机器的机制,用于在生物聚合物网络中产生收缩性.
- 为了解释没有基质极性要求的收缩性.
主要方法:
- 在生物聚合物网络中开发了无动力收缩性的理论模型.
- 嵌入了交叉连接器的活跃绑定-解绑动态.
- 考虑了半柔性生物聚合物的不对称的力延伸反应.
- 将模型扩展到粘弹性生物聚合物网络.
主要成果:
- 已经证明,收缩性来自于积极的交叉连接器动态,破坏了详细平衡.
- 表明不对称的聚合物强力延伸特性有助于收缩.
- 使用微观模型计算的收缩速度,可简化为粗粒度模型.
- 为细胞中观察到的运动独立收缩性提供了潜在的解释.
结论:
- 无电机收缩性可以通过活性交叉连接器动力学和聚合物力学来实现.
- 拟议的机制提供了关于细胞收缩性和合成活性材料的见解.
- 这项工作扩大了对生物聚合物系统中力生成的理解.
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