Del Junco Clara, Estevez-Torres André, Maitra Ananyo
Department of Chemistry and Department of Sociology, University of Chicago, Chicago, Illinois 60637, USA and Wesleyan University Library, Middletown, Connecticut 06459, USA.
Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire Jean Perrin (LJP), F-75005, Paris.
Phys Rev E. 2022 Jan;105(1-1):014602. doi: 10.1103/PhysRevE.105.014602.
Spontaneous pattern formation in living systems is driven by reaction-diffusion chemistry and active mechanics. The feedback between chemical and mechanical forces is often essential to robust pattern formation, yet it remains poorly understood in general. In this analytical and numerical paper, we study an experimentally motivated minimal model of coupling between reaction-diffusion and active matter: a propagating front of an autocatalytic and stress-generating species. In the absence of activity, the front is described by the well-studied Kolmogorov, Petrovsky, and Piskunov equation. We find that front propagation is maintained even in active systems, with crucial differences: an extensile stress increases the front speed beyond a critical magnitude of the stress, while a contractile stress has no effect on the front speed but can generate a periodic instability in the high-concentration region behind the front. We expect our results to be useful in interpreting pattern formation in active systems with mechanochemical coupling in vivo and in vitro.
生命系统中的自发模式形成是由反应扩散化学和主动力学驱动的。化学力和机械力之间的反馈对于稳健的模式形成通常至关重要，但总体上仍知之甚少。在这篇分析与数值研究论文中，我们研究了一个受实验启发的反应扩散与活性物质耦合的最小模型：一种自催化且产生应力的物种的传播前沿。在没有活性的情况下，前沿由经过充分研究的柯尔莫哥洛夫、彼得罗夫斯基和皮斯库诺夫方程描述。我们发现，即使在活性系统中前沿传播也能维持，但存在关键差异：拉伸应力会使前沿速度增加到超过应力的临界大小，而收缩应力对前沿速度没有影响，但会在前沿后方的高浓度区域产生周期性不稳定性。我们期望我们的结果有助于解释体内和体外具有机械化学耦合的活性系统中的模式形成。
