Non-equilibrium raft-like membrane domains under continuous recycling

TL;DR

This paper models membrane raft assembly considering continuous recycling, showing that domain size distribution and average radius depend on recycling dynamics, aligning with biological observations and suggesting a universal size scale.

Contribution

The study introduces a model linking membrane recycling to raft domain size distribution, providing insights into cellular signaling and traffic.

Findings

Raft domains follow a broad power-law size distribution.

Average raft radius scales with the quarter power of domain lifetime.

Predicted raft sizes are consistent with biological measurements.

Abstract

We present a model for the kinetics of spontaneous membrane domain (raft) assembly that includes the effect of membrane recycling ubiquitous in living cells. We show that the domains have a broad power-law distribution with an average radius that scales with the 1/4 power of the domain lifetime when the line tension at the domain edges is large. For biologically reasonable recycling and diffusion rates the average domain radius is in the tens of nm range, consistent with observations. This represents one possible link between signaling (involving rafts) and traffic (recycling) in cells. Finally, we present evidence that suggests that the average raft size may be the same for all scale-free recycling schemes.