Rhodopsin forms a dimer with cytoplasmic helix 8 contacts in native membranes.
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ABSTRACT:
SUBMITTER: Knepp AM
PROVIDER: S-EPMC3332060 | biostudies-literature | 2012 Mar
REPOSITORIES: biostudies-literature
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Rhodopsin forms a dimer with cytoplasmic helix 8 contacts in native membranes.
Knepp Adam M AM Periole Xavier X Marrink Siewert-Jan SJ Sakmar Thomas P TP Huber Thomas T
Biochemistry 20120227 9
G protein-coupled receptors form dimers and higher-order oligomers in membranes, but the precise mode of receptor-receptor interaction remains unknown. To probe the intradimeric proximity of helix 8 (H8), we conducted chemical cross-linking of endogenous cysteines in rhodopsin in disk membranes. We identified a Cys316-Cys316 cross-link using partial proteolysis and liquid chromatography with mass spectrometry. These results show that a symmetric dimer interface mediated by H1 and H8 contacts is ...[more]
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