Pulsatory patterns in active viscoelastic fluids with distinct relaxation time scales

TL;DR

This paper demonstrates that having separate shear and areal relaxation times in a minimal active gel model is enough to produce pulsatile dynamics in active surfaces, shedding light on tissue patterning mechanisms.

Contribution

It introduces a minimal model incorporating distinct shear and areal relaxation times to explain pulsatile behaviors in active viscoelastic tissues.

Findings

Distinct relaxation times induce pulsatile dynamics

Model explains tissue patterning mechanisms

Highlights importance of viscoelastic properties

Abstract

Developing tissues need to pattern themselves in space and time. A prevalent mechanism to achieve this are pulsatile active stresses generated by the actin cytoskeleton. Active gel theory is a powerful tool to model the dynamics of cytoskeletal pattern formation. In theoretical models, the influence of the viscoelastic nature of the actin cytoskeleton has so far only been investigated by the incorporation of one viscoelastic relaxation time scale. Here, using a minimal model of active gel theory with a single molecular regulator, we show that distinct shear and areal relaxation times are sufficient to drive pulsatile dynamics in active surfaces.