Protein Drift-Diffusion in Membranes with Non-equilibrium Fluctuations arising from Gradients in Concentration or Temperature

TL;DR

This paper develops simulation methods based on non-equilibrium statistical mechanics to model protein drift-diffusion in membranes with spatially varying concentration and temperature, capturing complex biophysical dynamics.

Contribution

It introduces self-consistent hybrid models for protein dynamics in heterogeneous membranes, incorporating non-equilibrium fluctuations and thermal effects, advancing understanding of membrane biophysics.

Findings

Models reveal how concentration gradients influence protein positioning.

Thermal gradients affect Brownian motion and energy exchange.

Simulation methods can be applied to other biological and soft matter systems.

Abstract

We investigate proteins within heterogeneous cell membranes where non-equilibrium phenomena arises from spatial variations in concentration and temperature. We develop simulation methods building on non-equilibrium statistical mechanics to obtain stochastic hybrid continuum-discrete descriptions which track individual protein dynamics, spatially varying concentration fluctuations, and thermal exchanges. We investigate biological mechanisms for protein positioning and patterning within membranes and factors in thermal gradient sensing. We also study the kinetics of Brownian motion of particles with temperature variations within energy landscapes arising from heterogeneous microstructures within membranes. The introduced approaches provide self-consistent models for studying biophysical mechanisms involving the drift-diffusion dynamics of individual proteins and energy exchanges and fluctuations between the thermal and mechanical parts of the system. The methods also can be used for studying related non-equilibrium effects in other biological systems and soft materials.