title: Strategies for studying the ligand binding site of GPCRs: photoaffinity labeling of the VPAC1 receptor, a prototype of class B GPCRs.
abstract: G protein-coupled receptors (GPCRs) are crucial receptors acting as molecular sensors for many physiological and pathological processes. Class B GPCRs represent a small GPCR subfamily encompassing 15 members, and are very promising targets for the development of drugs to improve many diseases such as chronic inflammation, neurodegeneration, diabetes, stress, and osteoporosis. Over the past decade, structure-function relationship studies have demonstrated that the N-terminal ectodomain (N-ted) of class B GPCRs plays a pivotal role in natural ligand recognition. The N-ted structure of some class B GPCRs folds into a Sushi domain consisting of two antiparallel β sheets stabilized by three disulfide bonds and a salt bridge. The VPAC1 receptor is an archetype of class B GPCRs that binds vasoactive intestinal peptide (VIP), a neuropeptide modulating many physiological processes. The structure-function relationship of VPAC1 has been extensively studied. The use of a photoaffinity labeling strategy has been a powerful approach to determine the physical contacts between the functional receptor and its ligand. Those studies, coupled with 3D molecular modeling techniques, have clearly demonstrated the crucial role of the VPAC1 receptor N-ted in VIP recognition.
authors: INSERM 773/Centre de Recherche Biomédicale Bichat Beaujon (CRB3), Faculté de Médecine Xavier Bichat, Université Paris, Paris, France. alain.couvineau@inserm.fr
authors: Alain
authors: A
authors: Couvineau
authors: Yossan-Var
authors: YV
authors: Tan
authors: Emilie
authors: E
authors: Ceraudo
authors: Marc
authors: M
authors: Laburthe
mesh_terms: D000818:Animals; D001665:Binding Sites; D006801:Humans; D017433:Protein Structure, Secondary; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry / Q000378:metabolism*; D051238:Receptors, Vasoactive Intestinal Polypeptide, Type I / Q000737:chemistry / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014660:Vasoactive Intestinal Peptide / Q000737:chemistry / Q000378:metabolism
chemical_list: D043562:Receptors, G-Protein-Coupled; D051238:Receptors, Vasoactive Intestinal Polypeptide, Type I; D014660:Vasoactive Intestinal Peptide