Mobility of cell surface receptors: a re-evaluation

It has long been known from fluorescence recovery after photobleaching experiments that the mobility of most cell surface receptors is much smaller than expected for free diffusion of proteins in a fluid lipid bilayer, Single-particle tracking experiments are currently revealing the complexity of the constraints to free diffusion. Evidence has been obtained for several different processes: domain-limited diffusion, temporary confinement and anomalous diffusion. The type of motion exhibited by a given receptor mill profoundly influence the rate of any functional process which requires movement in the plane of the membrane. In particular; anomalous diffusion greatly reduces the distance travelled by a receptor on a time scale of minutes, (C) 1998 Federation of European Biochemical Societies.