title: Rhodopsin forms a dimer with cytoplasmic helix 8 contacts in native membranes.
abstract: 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 present in native membranes.
authors.affiliation: Laboratory of Molecular Biology and Biochemistry, The Rockefeller University, New York, New York 10065, United States.
authors.forename: Adam M
authors.initials: AM
authors.lastname: Knepp
authors.forename: Xavier
authors.initials: X
authors.lastname: Periole
authors.forename: Siewert-Jan
authors.initials: SJ
authors.lastname: Marrink
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Sakmar
authors.forename: Thomas
authors.initials: T
authors.lastname: Huber
mesh_terms: D001665:Binding Sites; D002462:Cell Membrane / Q000378:metabolism*; D002853:Chromatography, Liquid; D003545:Cysteine / Q000737:chemistry / Q000235:genetics; D003593:Cytoplasm / Q000378:metabolism*; D019281:Dimerization; D013058:Mass Spectrometry; D017433:Protein Structure, Secondary; D059748:Proteolysis; D012243:Rhodopsin / Q000737:chemistry* / Q000378:metabolism
chemical_list: D012243:Rhodopsin; D003545:Cysteine