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The structure and function of G-protein-coupled receptors


G-protein-coupled receptors (GPCRs) mediate most of our physiological responses to hormones, neurotransmitters and environmental stimulants, and so have great potential as therapeutic targets for a broad spectrum of diseases. They are also fascinating molecules from the perspective of membrane-protein structure and biology. Great progress has been made over the past three decades in understanding diverse GPCRs, from pharmacology to functional characterization in vivo. Recent high-resolution structural studies have provided insights into the molecular mechanisms of GPCR activation and constitutive activity.

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Figure 1: Signal transduction in G-protein-coupled receptors.
Figure 2: Comparison of four GPCR structures.
Figure 3: Comparison of conserved regions of four GPCR structures.
Figure 4: The structure of opsin obtained at low pH represents an active form of rhodopsin.


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This work was supported by the US National Institute of General Medical Sciences (grant F32 GM082028 to D.M.R. and grant RO1-GM083118 to B. K.), the Lundbeck Foundation (to S.G.F.R.), the National Institute of Neurological Disorders and Stroke (grant RO1-NS28471 to B.K.) and the Mather Charitable Foundation (to B. K.).

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Rosenbaum, D., Rasmussen, S. & Kobilka, B. The structure and function of G-protein-coupled receptors. Nature 459, 356–363 (2009).

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