Robust statistical properties of T1 transitions in confluent cell tissues

TL;DR

This paper investigates the statistical and dynamical properties of T1 cell rearrangements in confluent tissues, revealing a robust energy profile and their role in large-scale tissue deformation and flow.

Contribution

It introduces a robust energy profile for T1 transitions and elucidates their role in propagating tissue deformation through local cell rearrangements.

Findings

Energy profile of T1 transitions is robust to parameter changes.

T1 transitions induce large local cell deformations.

T1 transitions propagate tissue flows through chaining effects.

Abstract

Large-scale tissue deformation which is fundamental to tissue development hinges on local cellular rearrangements, such as T1 transitions. In the realm of the multi-phase field model, we analyse the statistical and dynamical properties of T1 transitions in a confluent tissue. We identify an energy profile that is robust to changes in several model parameters. It is characterized by an asymmetric profile with a fast increase in energy before the T1 transition and a sudden drop after the T1 transition, followed by a slow relaxation. The latter being a signature of the fluidity of the cell tissue. We show that T1 transitions are sources of localised large deformation of the cells undergoing the neighbour exchange and induce other T1 transitions in the nearby cells through a chaining of events that propagate local cell deformation to large scale tissue flows.