G protein-coupled receptors are cell-surface seven-helical membrane proteins that undergo conformational changes on activation. The mammalian photoreceptor, rhodopsin, is the best-studied member of this superfamily. Here, we provide the first evidence that activation in rhodopsin may involve differential dynamic properties of side-chain versus backbone atoms. High-resolution NMR studies of α-15N-labeled receptor revealed large backbone motions in the inactive dark state. In contrast, indole side-chain 15N groups of tryptophans showed well resolved, equally intense NMR signals, suggesting restriction to a single specific conformation.
|Original language||English (US)|
|Number of pages||5|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - Mar 9 2004|
ASJC Scopus subject areas