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arXiv · 1611.09289

Thermodynamic competition between membrane protein oligomeric states

Osman Kahraman·Christoph A. Haselwandter
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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.

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Osman Kahraman, Christoph A. Haselwandter. 2016-11-28. Thermodynamic competition between membrane protein oligomeric states. https://doi.org/10.1209/0295-5075/116/28005

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