Thermodynamic competition between membrane protein oligomeric states

Department of Physics & Astronomy and Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California - Los Angeles, CA 90089, USA

Received: 25 August 2016
Accepted: 8 November 2016

Abstract

Self-assembly of protein monomers into distinct membrane protein oligomers provides a general mechanism for diversity in the molecular architectures, and resulting biological functions, of membrane proteins. We develop a general physical framework describing the thermodynamic competition between different oligomeric states of membrane proteins. Using the mechanosensitive channel of large conductance as a model system, we show how the dominant oligomeric states of membrane proteins emerge from the interplay of protein concentration in the cell membrane, protein-induced lipid bilayer deformations, and direct monomer-monomer interactions. Our results suggest general physical mechanisms and principles underlying regulation of protein function via control of membrane protein oligomeric state.