Critical Casimir forces in cellular membranes

TL;DR

This paper explores how critical Casimir forces, arising from membrane composition fluctuations near a critical point, can mediate long-range interactions between membrane proteins in living cells, with theoretical and simulation support.

Contribution

It introduces a theoretical framework for understanding membrane protein interactions via critical Casimir forces using conformal field theory and Monte Carlo simulations.

Findings

Membrane proteins experience weak but long-range forces.

Critical fluctuations significantly influence membrane protein interactions.

Theoretical predictions are validated by Monte Carlo simulations.

Abstract

Recent experiments suggest that membranes of living cells are tuned close to a miscibility critical point in the 2D Ising universality class. We propose that one role for this proximity to criticality in live cells is to provide a conduit for relatively long-ranged critical Casimir forces. Using techniques from conformal field theory we calculate potentials of mean force between membrane bound inclusions mediated by their local interactions with the composition order parameter. We verify these calculations using Monte-Carlo where we also compare critical and off-critical results. Our findings suggest that membrane bound proteins experience weak yet long range forces mediated by critical composition fluctuations in the plasma membranes of living cells.