Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA 19104, USA.
J R Soc Interface. 2024 Jan;21(210):20230543. doi: 10.1098/rsif.2023.0543. Epub 2024 Jan 17.
The aim of this paper is to place the cell locomotion problem within the general framework of classical continuum mechanics, and while doing so, to account for the deformation of the actin network in the cytoskeleton; the myosin activity on the lamellum including its effect on depolymerization at the trailing edge; model the stress-dependent driving forces and kinetic laws controlling polymerization at the leading edge, depolymerization at the trailing edge and ATP hydrolysis consistently with the dissipation inequality; and, based on the observations in Gardel (Gardel 2008 , 999-1005 (doi:10.1083/jcb.200810060)), include a biphasic velocity-dependent traction stress acting on the actin network. While we chose certain specific models for each of these, in part to allow for an analytical solution, the generality of the framework allows one to readily introduce different constitutive laws to describe these phenomena as might be needed, for example, to study some different type of cells. As described in §5, the predictions of the model compare well with observations such as the magnitude of the very different actin retrograde speeds in the lamellum and lamellipodium including their jump at the interface, the magnitude of the cell speed, and the relative lengths of the lamellipodium and lamellum.
本文旨在将细胞迁移问题置于经典连续介质力学的一般框架内，并在此过程中考虑细胞骨架中肌动蛋白网络的变形；在翼片上的肌球蛋白活性，包括其对尾部解聚的影响；一致地用耗散不等式来模拟控制前缘聚合、尾部解聚和 ATP 水解的依赖于应力的驱动力和动力学定律；并且，基于 Gardel 的观察结果 (Gardel 2008, 999-1005 (doi:10.1083/jcb.200810060))，包括作用于肌动蛋白网络的双相速度依赖性牵引力。虽然我们为每个模型选择了某些特定的模型，部分原因是为了允许分析解，但是该框架的通用性允许人们很容易地引入不同的本构定律来描述这些现象，例如，研究一些不同类型的细胞。如第 5 节所述，该模型的预测与观察结果非常吻合，例如翼片中非常不同的肌动蛋白逆行速度及其在界面处的跳跃、细胞速度的大小以及翼片和翼片的相对长度。
