Hawkins R J, Piel M, Faure-Andre G, Lennon-Dumenil A M, Joanny J F, Prost J, Voituriez R
UMR 7600, Université Pierre et Marie Curie/CNRS, 4 Place Jussieu, 75255 Paris Cedex 05 France.
Phys Rev Lett. 2009 Feb 6;102(5):058103. doi: 10.1103/PhysRevLett.102.058103. Epub 2009 Feb 5.
We propose a novel mechanism of cell motility, which relies on the coupling of actin polymerization at the cell membrane to geometric confinement. We consider a polymerizing viscoelastic cytoskeletal gel confined in a narrow channel, and show analytically that spontaneous motion occurs. Interestingly, this does not require specific adhesion with the channel walls, and yields velocities potentially larger than the polymerization velocity. The contractile activity of myosin motors is not necessary to trigger motility in this mechanism, but is shown quantitatively to increase the velocity. Our model qualitatively accounts for recent experiments which show that cells without specific adhesion proteins are motile only in confined environments while they are unable to move on a flat surface, and could help in understanding the mechanisms of cell migration in more complex confined geometries such as living tissues.
我们提出了一种新的细胞运动机制，该机制依赖于细胞膜上肌动蛋白聚合与几何限制的耦合。我们考虑一种聚合的粘弹性细胞骨架凝胶被限制在一个狭窄的通道中，并通过分析表明会发生自发运动。有趣的是，这并不需要与通道壁有特定的粘附，并且产生的速度可能大于聚合速度。在这种机制中，肌球蛋白马达的收缩活性并非触发运动所必需的，但定量分析表明它会增加速度。我们的模型定性地解释了最近的实验，这些实验表明没有特定粘附蛋白的细胞仅在受限环境中具有运动能力，而在平坦表面上无法移动，并且有助于理解细胞在更复杂的受限几何结构（如活组织）中的迁移机制。
