Lateral diffusion in heterogeneous cell membranes

Abstract

The plasma membrane is organized at numerous levels as a result of its large variety of molecular constituents and of selective interactions between them. Lateral diffusion, a direct physical consequence of the Brownian agitation, plays a key organizational role by constantly redistributing the membrane constituents among the possible molecular associations. In this context, we will first review the physical mechanisms contributing to the creation of inhomogeneity. We will then describe the current methodological approaches allowing us to measure diffusion in living cells. The different levels of membrane organization will be discussed before illustrating the impact of the dynamic organization of the membrane on cellular functions.