Directional interactions and cooperativity between mechanosensitive membrane proteins

¹ Department of Physics and Astronomy, University of Southern California - Los Angeles, CA 90089, USA
² Department of Applied Physics, California Institute of Technology - Pasadena, CA 91125, USA

Received: 18 January 2013
Accepted: 25 February 2013

Abstract

While modern structural biology has provided us with a rich and diverse picture of membrane proteins, the biological function of membrane proteins is often influenced by the mechanical properties of the surrounding lipid bilayer. Here we explore the relation between the shape of membrane proteins and the cooperative function of membrane proteins induced by membrane-mediated elastic interactions. For the experimental model system of mechanosensitive ion channels we find that the sign and strength of elastic interactions depend on the protein shape, yielding distinct cooperative gating curves for distinct protein orientations. Our approach predicts how directional elastic interactions affect the molecular structure, organization, and biological function of proteins in crowded membranes.