肌力引起F-actin结构格局,该格局介导机械敏感蛋白质识别
Ayala G Carl1,2, Matthew J Reynolds1, Pinar S Gurel1
1Laboratory of Structural Biophysics and Mechanobiology, The Rockefeller University, New York, NY, USA.
bioRxiv : the preprint server for biology
|August 26, 2024
概括
肌素的作用力将动氨酸丝 (F-actin) 重塑成螺旋,改变它们的结构. 这种机械变形被α-catenin识别,揭示了细胞如何感知和响应物理力量的新机制.
科学领域:
- 细胞力学 细胞力学
- 生物物理学的生物物理.
- 分子和结构生物学 分子和结构生物学
背景情况:
- 细胞通过细胞骨连接的粘合物与它们的环境相互作用.
- 来自环境的机械线索影响细胞发育和癌症等疾病.
- 肌运动蛋白产生力用于机械信号转导,但结构机制尚不清楚.
研究的目的:
- 为了研究氨酸力量是如何结构性地改变actin丝 (F-actin) 的.
- 了解这些F-actin结构变化如何影响像α-catenin这样的机械敏感蛋白质的结合.
- 阐明细胞中机械信号传导的结构机制.
主要方法:
- 相关的冷-光显微镜和冷电子断层扫描.
- 开发一种复制系统,以可视化F-actin与肌力量的复制.
- 低温电子显微镜和F-actin结构的3D重建.
- 在力下的F-actin的分子动力学模拟.
主要成果:
- 识别了F-actin,它具有纳米级振荡曲率,在产生力界面上富含zyxin.
- 揭示的肌素力量在体外诱导超螺旋式F-actin螺旋.
- 证明F-actin螺旋是由于actin网格的不对称重塑而产生的.
- 显示α-catenin与这些变形的F-actin结构合作结合,调节其相互作用.
结论:
- 肌力积极地使F-actin变形为螺旋形状.
- 这种强力诱导的结构变化产生了由α-catenin识别的特定景观.
- 提供了直接的结构证据,证明了通过细胞骨的力传导和粘附蛋白的机械感知.
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