Signatures of protein structure in the cooperative gating of mechanosensitive ion channels

¹ Departments of Physics & Astronomy and Biological Sciences, University of Southern California Los Angeles, CA 90089, USA
² Department of Mechanical and Aerospace Engineering, University of California, Los Angeles Los Angeles, CA 90095, USA

Received: 5 June 2014
Accepted: 4 August 2014

Abstract

Membrane proteins deform the surrounding lipid bilayer, which can lead to membrane-mediated interactions between neighboring proteins. Using the mechanosensitive channel of large conductance (MscL) as a model system, we demonstrate how the observed differences in protein structure can affect membrane-mediated interactions and cooperativity among membrane proteins. We find that distinct oligomeric states of MscL lead to distinct gateway states for the clustering of MscL, and predict signatures of MscL structure and spatial organization in the cooperative gating of MscL. Our modeling approach establishes a quantitative relation between the observed shapes and the cooperative function of membrane proteins.