Mechanical factors affecting the mobility of membrane proteins

TL;DR

This paper reviews the limitations of the Saffman-Delbrück model for membrane protein mobility and introduces a polaron-like model that incorporates mechanical factors and protein-membrane coupling to better explain experimental observations.

Contribution

It proposes a new polaron-like model that accounts for mechanical factors affecting membrane protein mobility, extending previous models and highlighting the importance of protein-membrane coupling.

Findings

The Saffman-Delbrück model does not fully explain experimental data.

A polaron-like model better captures mechanical influences on mobility.

Extensions of the model can incorporate various protein-membrane interactions.

Abstract

The mobility of membrane proteins controls many biological functions. The application of the model of Saffman and Delbr\"uck to the diffusion of membrane proteins does not account for all the experimental measurements. These discrepancies have triggered a lot of studies on the role of the mechanical factors in the mobility. After a short review of the Saffman and Delbr\"uck model and of some key experiments, we explore the various ways to incorporate the effects of the different mechanical factors. Our approach focuses on the coupling of the protein to the membrane, which is the central element in the modelling. We present a general, polaron-like model, its recent application to the mobility of a curvature sensitive protein, and its various extensions to other couplings that may be relevant in future experiments.