"Rigidity transition in epithelial tissues"
Primož Ziherl
University of Ljubljana and Jožef Stefan Institute, Ljubljana (Slovenia)

Friday 14/11/2025 11:00
Live streaming: Teams link

Single-cell-thick epithelia are among the simplest types of tissues, and they were shown to undergo a liquid-solid transition aka. jamming or rigidity transition, the latter indicating a finite shear modulus in the solid phase. The mechanics of these tissues, which is governed by forces generated in various cell regions, is often investigated using two-dimensional models that account for the apically positioned actomyosin structures but neglect basolateral mechanics. We employ a more detailed three-dimensional model to study how lateral surface tensions affect the structure and rigidity of such tissues. We find that cells are apicobasally asymmetric, with one side appearing more ordered than the other depending on target cell apical perimeter. In contrast to the 2D model, which predicts a rigidity transition at large target perimeters, tissues in the 3D model remain solidlike across all parameter space. This opens the question of the mechanism and the origin of the rigidity transition.