Random traction yielding transition in epithelial tissues

TL;DR

This study reveals a critical transition in epithelial tissues where randomly oriented cell traction forces cause fluidisation, exhibiting unique critical behaviour distinct from traditional amorphous solids.

Contribution

It introduces a novel fluidisation mechanism in epithelial tissues driven by active force generation, with a detailed analysis of its critical properties and universality class.

Findings

Fluidisation occurs at a critical traction force magnitude $F_c$.

The transition exhibits critical behaviour similar to yielding in amorphous solids.

The transition belongs to a different universality class than sheared amorphous solids.

Abstract

We investigate how randomly oriented cell traction forces lead to fluidisation in a vertex model of epithelial tissues. We find that the fluidisation occurs at a critical value of the traction force magnitude $F_c$. We show that this transition exhibits critical behaviour, similar to the yielding transition of sheared amorphous solids. However, we find that it belongs to a different universality class, even though it satisfies the same scaling relations between critical exponents established in the yielding transition of sheared amorphous solids. Our work provides a fluidisation mechanism through active force generation that could be relevant in biological tissues.