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Experimental evidence for membrane-mediated protein-protein interaction.

ABSTRACT: Membrane proteins diffuse within the membrane, form oligomers and supramolecular assemblies. Using high-speed atomic force microscopy, we present direct experimental measure of an in-membrane-plane interaction potential between membrane proteins. In purple membranes, ATP-synthase c-rings formed dimers that temporarily dissociated. C-ring dimers revealed subdiffusive motion, while dissociated monomers diffused freely. C-rings center-to-center distance probability distribution allowed the calculation and modeling of an in-membrane-plane energy landscape that presented repulsion at 80 Å, most stable dimer association at 103 Å (-3.5 k(B)T strength), and dissociation at 125 Å (-1 k(B)T strength). This first experimental data of nonlabeled membrane protein diffusion and the corresponding in-membrane-plane interaction energy landscape characterized membrane protein interaction with an attractive range of several k(B)T that reaches to a radius of ?50 Å within the membrane plane.

SUBMITTER: Casuso I

PROVIDER: S-EPMC3042552 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Experimental evidence for membrane-mediated protein-protein interaction.

Casuso Ignacio I Sens Pierre P Rico Felix F Scheuring Simon S

Biophysical journal 20101001 7

Membrane proteins diffuse within the membrane, form oligomers and supramolecular assemblies. Using high-speed atomic force microscopy, we present direct experimental measure of an in-membrane-plane interaction potential between membrane proteins. In purple membranes, ATP-synthase c-rings formed dimers that temporarily dissociated. C-ring dimers revealed subdiffusive motion, while dissociated monomers diffused freely. C-rings center-to-center distance probability distribution allowed the calculat ...[more]

PMID: 20923630

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