Undulation of a moving fluid membrane pushed by filament growth

Abstract Biomembranes experience out-of-equilibrium conditions in living cells. Their undulation spectra are different from those thermal equilibrium. Here, we report on the of a fluid membrane pushed by stepwise growth filaments as leading edge migrating cells, using three-dimensional Monte Carlo simulations. The undulations largely modified equilibrium behavior. When tension is constrained, low-wave-number modes suppressed or enhanced at small large step sizes, respectively, for high surface tensions. In contrast, they always tensionless membrane, wherein wave-number range suppression depends size. area addition to these features, specific mode excited zero and low reduction first induces buckling lowest wave-number, subsequently, other excited, steady state.