小柯机器人

美国加州大学Orion D. Weiner，Carlos Bustamante和法国PSL大学Hervé Turlier共同合作，近期取得重要工作进展。他们研究发现细胞突起和收缩可以产生长程膜张力传播。相关研究成果2023年6月12日在线发表于《细胞》杂志上。

据介绍，膜张力被认为是细胞生理学的长期整合因子。膜张力已被提出通过前后协调和长距离突起竞争使细胞在迁移过程中具有极性。这些作用需要在细胞中有效地传递张力。然而，相互矛盾的观察结果使该领域在细胞膜是支持还是抵抗张力传播方面存在分歧。这种差异可能源于无法准确模仿内生力的外力的使用。

研究人员通过利用光遗传学直接控制基于肌动蛋白的局部突起或肌动球蛋白收缩，同时使用dual-trap光镊监测膜张力的传播，克服了这一复杂性。研究人员发现，肌动蛋白驱动的突起和肌动球蛋白收缩都能引发快速的全局膜张力传播，而单独施加在细胞膜上的力则不能。

总之，研究人员提出了一个简单的统一力学模型，其中与肌动蛋白皮层接触的机械力通过长程膜流驱动快速、稳健的膜张力传播。

附：英文原文

Title: Cell protrusions and contractions generate long-range membrane tension propagation

Author: Henry De Belly, Shannon Yan, Hudson Borja da Rocha, Sacha Ichbiah, Jason P. Town, Patrick J. Zager, Dorothy C. Estrada, Kirstin Meyer, Hervé Turlier, Carlos Bustamante, Orion D. Weiner

Issue&Volume: 2023-06-12

Abstract: Membrane tension is thought to be a long-range integrator of cell physiology. Membrane tension has been proposed to enable cell polarity during migration through front-back coordination and long-range protrusion competition. These roles necessitate effective tension transmission across the cell. However, conflicting observations have left the field divided as to whether cell membranes support or resist tension propagation. This discrepancy likely originates from the use of exogenous forces that may not accurately mimic endogenous forces. We overcome this complication by leveraging optogenetics to directly control localized actin-based protrusions or actomyosin contractions while simultaneously monitoring the propagation of membrane tension using dual-trap optical tweezers. Surprisingly, actin-driven protrusions and actomyosin contractions both elicit rapid global membrane tension propagation, whereas forces applied to cell membranes alone do not. We present a simple unifying mechanical model in which mechanical forces that engage the actin cortex drive rapid, robust membrane tension propagation through long-range membrane flows.

DOI: 10.1016/j.cell.2023.05.014

Source: https://www.cell.com/cell/fulltext/S0092-8674(23)00533-0