Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.
Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622, Villeurbanne, France.
Sci Rep. 2021 Apr 12;11(1):7985. doi: 10.1038/s41598-021-87073-6.
Biomembranes experience out-of-equilibrium conditions in living cells. Their undulation spectra are different from those in thermal equilibrium. Here, we report on the undulation of a fluid membrane pushed by the stepwise growth of filaments as in the leading edge of migrating cells, using three-dimensional Monte Carlo simulations. The undulations are largely modified from equilibrium behavior. When the tension is constrained, the low-wave-number modes are suppressed or enhanced at small or large growth step sizes, respectively, for high membrane surface tensions. In contrast, they are always suppressed for the tensionless membrane, wherein the wave-number range of the suppression depends on the step size. When the membrane area is constrained, in addition to these features, a specific mode is excited for zero and low surface tensions. The reduction of the undulation first induces membrane buckling at the lowest wave-number, and subsequently, other modes are excited, leading to a steady state.
生物膜在活细胞中经历非平衡状态。它们的波动谱与热平衡时不同。在这里，我们使用三维蒙特卡罗模拟报告了在丝状生长推动下流体膜的波动，如在迁移细胞的前沿。波动在很大程度上偏离了平衡行为。当张力受到限制时，对于高膜表面张力，小或大的生长步长分别抑制或增强低波数模式。相比之下，对于无张力膜，它们总是被抑制，其中抑制的波数范围取决于步长。当膜面积受到限制时，除了这些特征外，对于零和低表面张力还会激发特定模式。波动的减少首先在最低波数处引起膜的屈曲，随后，其他模式被激发，导致稳定状态。
