Spatial signal amplification in cell biology: a lattice-gas model for self-tuned phase ordering

TL;DR

This paper introduces a lattice-gas model explaining how cell membrane phase separation amplifies external chemical signals and self-tunes enzyme concentrations, elucidating a key mechanism in cell motility regulation.

Contribution

It presents a novel lattice model incorporating short-range attraction and long-range repulsion to explain phase separation and self-tuning in cell membrane enzyme dynamics.

Findings

Model reproduces observed phase coexistence behavior.

Explains self-tuning of enzyme concentrations across varying attractant levels.

Provides physical basis for long-range repulsion in membrane phase separation.

Abstract

Experiments show that the movement of eukaryotic cells is regulated by a process of phase separation of two competing enzymes on the cell membrane, that effectively amplifies shallow external gradients of chemical attractant. Notably, the cell is able to self-tune the final enzyme concentrations to an equilibrium state of phase coexistence, for a wide range of the average attractant concentration. We propose a simple lattice model in which, together with a short-range attraction between enzymes, a long-range repulsion naturally arises from physical considerations, that easily explains such observed behavior.