A physical scenario accounting for the existence of size-limited
submicrometric domains in cell membranes is proposed. It is based on the
numerical investigation of the counterpart, in lipidic membranes where proteins
are diffusing, of the recently discovered cluster phases in colloidal
suspensions. I demonstrate that the interactions between proteins, namely
short-range attraction and longer-range repulsion, make possible the existence
of stable small clusters. The consequences are explored in terms of membrane
organization and diffusion properties. The connection with lipid rafts is
discussed and the apparent protein diffusion coefficient as a function of their
concentration is analyzed.Comment: 5 pages - enhanced versio