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Agonist-bound structures of G protein-coupled receptors

Institut de Génomique Fonctionnelle, UMR 5203 CNRS - U 661 INSERM - Univ. Montpellier I & II, 141, rue de la cardonille, 34094 Montpellier Cedex 05, France.
Current Opinion in Structural Biology (Impact Factor: 8.75). 04/2012; 22(4):482-90. DOI: 10.1016/j.sbi.2012.03.007
Source: PubMed

ABSTRACT G protein-coupled receptors (GPCRs) play a major role in intercellular communication by binding small diffusible ligands (agonists) at the extracellular surface. Agonist-binding induces a conformational change in the receptor, which results in the binding and activation of heterotrimeric G proteins within the cell. Ten agonist-bound structures of non-rhodopsin GPCRs published last year defined for the first time the molecular details of receptor activated states and how inverse agonists, partial agonists and full agonists bind to produce different effects on the receptor. In addition, the structure of the β(2)-adrenoceptor coupled to a heterotrimeric G protein showed how the opening of a cleft in the cytoplasmic face of the receptor as a consequence of agonist binding results in G protein coupling and activation of the G protein.

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