Giant fluctuations and structural effects in a flocking epithelium
Abstract
Epithelial cells cultured in a monolayer are very motile in isolation but reach a near-jammed state when mitotic division increases their number above a critical threshold. We have recently shown that a monolayer can be reawakened by over-expression of a single protein, RAB5A, a master regulator of endocytosis. This reawakening of motility was explained in term of a flocking transition that promotes the emergence of a large-scale collective migratory pattern. Here we focus on the impact of this reawakening on the structural properties of the monolayer. We find that the unjammed monolayer is characterised by a fluidisation at the single cell level and by enhanced non-equilibrium large-scale number fluctuations at a larger length scale. Also with the help of numerical simulations, we trace back the origin of these fluctuations to the self-propelled active nature of the constituents and to the existence of a local alignment mechanism, leading to the spontaneous breaking of the orientational symmetry.
Cite
@article{arxiv.1707.03060,
title = {Giant fluctuations and structural effects in a flocking epithelium},
author = {Fabio Giavazzi and Chiara Malinverno and Salvatore Corallino and Francesco Ginelli and Giorgio Scita and Roberto Cerbino},
journal= {arXiv preprint arXiv:1707.03060},
year = {2017}
}