Article

Differential dynamics in the G protein-coupled receptor rhodopsin revealed by solution NMR.

Department of Pharmacology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.74). 04/2004; 101(10):3409-13. DOI: 10.1073/pnas.0308713101
Source: PubMed

ABSTRACT 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 alpha-(15)N-labeled receptor revealed large backbone motions in the inactive dark state. In contrast, indole side-chain (15)N groups of tryptophans showed well resolved, equally intense NMR signals, suggesting restriction to a single specific conformation.

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