Junctional-fluctuation-mediated fluidization of multi-phase-field epithelial monolayers.

We analyze a multi-phase-field model for an epithelial monolayer with pairwise adhesions between neighboring cells following an Ornstein-Uhlenbeck process, representing the stochastic turnover of junctional molecular motors. These fluctuations in junctional adhesion result in rearrangements in the tissue, fluidizing it and producing diffusive cell motion. Similar junctional fluctuations have proven a very useful tool in the vertex model literature, and we hope they will be equally helpful to the multi-phase-field model approach. Moreover, we observe that the cells' effective diffusion coefficient depends nonmonotonically on the persistence time of the fluctuations, confirming results previously observed in the vertex model.