title: Architecture and Function of Mechanosensitive Membrane Protein Lattices.
abstract: Experiments have revealed that membrane proteins can form two-dimensional clusters with regular translational and orientational protein arrangements, which may allow cells to modulate protein function. However, the physical mechanisms yielding supramolecular organization and collective function of membrane proteins remain largely unknown. Here we show that bilayer-mediated elastic interactions between membrane proteins can yield regular and distinctive lattice architectures of protein clusters, and may provide a link between lattice architecture and lattice function. Using the mechanosensitive channel of large conductance (MscL) as a model system, we obtain relations between the shape of MscL and the supramolecular architecture of MscL lattices. We predict that the tetrameric and pentameric MscL symmetries observed in previous structural studies yield distinct lattice architectures of MscL clusters and that, in turn, these distinct MscL lattice architectures yield distinct lattice activation barriers. Our results suggest general physical mechanisms linking protein symmetry, the lattice architecture of membrane protein clusters, and the collective function of membrane protein lattices.
authors.affiliation: Departments of Physics &Astronomy and Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Osman
authors.initials: O
authors.lastname: Kahraman
authors.affiliation: Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Koch
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, CA 90095, USA.
authors.forename: William S
authors.initials: WS
authors.lastname: Klug
authors.affiliation: Departments of Physics &Astronomy and Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Haselwandter
mesh_terms: D000465:Algorithms; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry; D040542:Mechanotransduction, Cellular; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D015233:Models, Statistical; D011485:Protein Binding; D011487:Protein Conformation; D055503:Protein Multimerization; D013329:Structure-Activity Relationship
chemical_list: D008051:Lipid Bilayers; D008565:Membrane Proteins