Mathematical models of actin in cell motility and of swarms/schools in social aggregation

细胞骨架及其主要的生物聚合物肌动蛋白负责动物细胞的形状、运动和许多方面的功能。 近年来，我的团队已经模拟了肌动蛋白周转如何有助于细胞的运动性，以及信号传导成分（Rho家族GTP酶Cdc42，Rac，Rho和磷酸肌醇PIP，PIP2，PIP3）如何调节肌动蛋白动力学。响应于分级刺激，我们的“模型细胞”产生稳定的GTP酶和PI的内部谱，并启动持续的运动，与生物学一致。(We显示GTP酶作为空间开关工作，PI过滤噪声，并定义前面与后面。相对快速的PI扩散还导致从可能的模式的集合中选择Rho GTdR分布的独特模式。我们还组装了爬行细胞的初步2D模拟。

The cytoskeleton, and its major biopolymer, actin are responsible for the shape, motility, and many aspects of animal cell function. In recent years, my group has modelled how actin turnover contributes to protrusive cell motility, and how signalling components (Rho family GTPases Cdc42, Rac, Rho, and phosphoinositides PIP, PIP2, PIP3), regulate actin dynamics. In response to a graded stimulus, our "model cell" produces stable internal profiles of GTPases and PIs, and initiates persistent motility, consistent with the biology. (We showed that GTPases work as a spatial switch, PIs filter noise, and define the front vs. back. Relatively fast PI diffusion also leads to selection of a unique pattern of Rho GTPase distribution from a collection of possible patterns). We also assembled preliminary 2D simulations of a crawling cell.