Linking non-peptide ligand binding mode to activity at the human cholecystokinin-2 receptor.

Abstract : Given the importance of G-protein-coupled receptors as pharmacological targets in medicine, efforts directed at the understanding the molecular mechanism by which pharmacological compounds regulate their activity is of paramount importance. Here, we investigated at an atomic level the mechanism of inverse agonism and partial agonism of two high affinity, high selectivity very similar non-peptide ligands of the cholecystokinin-2 receptor (CCK2R) which differ by the absence or presence of a methyl group on their indole moiety. Using in silico, site-directed mutagenesis and pharmacological experiments, we demonstrated that these functionally different activities are due to differing anchoring modes of the two compounds to a residue of helix II (Thr-2.61) in the inactive state of the CCK2R. The binding mode of the inverse agonist allows the ligand to interact through its phenyl moiety with a key amino acid for CCK2R activation (Trp-6.48), preventing rotation of helix VI and, thus, CCK2R activation, whereas the partial agonist binds deeper into the binding pocket and closer to helix V, so that CCK2R activation is favored. This study on the molecular mechanism of ligand action opens the possibility of target-based optimization of G protein-coupled receptor non-peptide ligands.
Type de document :
Article dans une revue
Journal of Biological Chemistry, American Society for Biochemistry and Molecular Biology, 2008, 283 (51), pp.35860-8. 〈10.1074/jbc.M805513200〉
Liste complète des métadonnées

http://www.hal.inserm.fr/inserm-00408959
Contributeur : Marie Francoise Simon <>
Soumis le : mardi 4 août 2009 - 15:39:12
Dernière modification le : jeudi 20 août 2009 - 15:46:40

Lien texte intégral

Identifiants

Collections

Citation

Magali Foucaud, Esther Marco, Chantal Escrieut, Caroline Low, Barret Kalindjian, et al.. Linking non-peptide ligand binding mode to activity at the human cholecystokinin-2 receptor.. Journal of Biological Chemistry, American Society for Biochemistry and Molecular Biology, 2008, 283 (51), pp.35860-8. 〈10.1074/jbc.M805513200〉. 〈inserm-00408959〉

Partager

Métriques

Consultations de la notice

102