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Structural insights into G-protein-coupled receptor activation.

ABSTRACT: G-protein-coupled receptors (GPCRs) are the largest family of eukaryotic plasma membrane receptors, and are responsible for the majority of cellular responses to external signals. GPCRs share a common architecture comprising seven transmembrane (TM) helices. Binding of an activating ligand enables the receptor to catalyze the exchange of GTP for GDP in a heterotrimeric G protein. GPCRs are in a conformational equilibrium between inactive and activating states. Crystallographic and spectroscopic studies of the visual pigment rhodopsin and two beta-adrenergic receptors have defined some of the conformational changes associated with activation.

SUBMITTER: Weis WI

PROVIDER: S-EPMC4019673 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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Structural insights into G-protein-coupled receptor activation.

Weis William I WI Kobilka Brian K BK

Current opinion in structural biology 20081117 6

G-protein-coupled receptors (GPCRs) are the largest family of eukaryotic plasma membrane receptors, and are responsible for the majority of cellular responses to external signals. GPCRs share a common architecture comprising seven transmembrane (TM) helices. Binding of an activating ligand enables the receptor to catalyze the exchange of GTP for GDP in a heterotrimeric G protein. GPCRs are in a conformational equilibrium between inactive and activating states. Crystallographic and spectroscopic ...[more]

PMID: 18957321

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