An alternative scenario for the formation of specialized protein nano-domains (cluster phases) in biomembranes
Université de Toulouse; UPS; Laboratoire de Physique Théorique (IRSAMC) - F-31062 Toulouse, France, EU
2 CNRS; LPT (IRSAMC) - F-31062 Toulouse, France, EU
Accepted: 19 August 2010
We discuss a realistic scenario, accounting for the existence of sub-micrometric protein domains in cell membranes. At the biological level, such membrane domains have been shown to be specialized, in order to perform a determined biological task, in the sense that they gather one or a few protein species out of the hundreds of different ones that a cell membrane may contain. By analyzing the balance between mixing entropy and protein affinities, we propose that such protein sorting in distinct domains can be explained without appealing to pre-existing lipidic micro-phase separations, as in the lipid raft scenario. We show that the proposed scenario is compatible with known physical interactions between membrane proteins, even if thousands of different species coexist.
PACS: 87.15.km – Protein-protein interactions / 05.65.+b – Self-organized systems / 87.16.A- – Theory, modeling, and simulations
© EPLA, 2010