title: Peroxisome proliferator-activated receptor structures: ligand specificity, molecular switch and interactions with regulators.
abstract: Peroxisome proliferator-activated receptors (PPARs) compose a family of nuclear receptors that mediate the effects of lipidic ligands at the transcriptional level. In this review, we highlight advances in the understanding of the PPAR ligand binding domain (LBD) structure at the atomic level. The overall structure of PPARs LBD is described, and important protein ligand interactions are presented. Structure-activity relationships between isotypes structures and ligand specificity are addressed. It is shown that the numerous experimental three-dimensional structures available, together with in silico simulations, help understanding the role played by the activating function-2 (AF-2) in PPARs activation and its underlying molecular mechanism. The relation between the PPARs constitutive activity and the intrinsic stability of the active conformation is discussed. Finally, the interactions of PPARs LBD with co-activators or co-repressors, as well as with the retinoid X receptor (RXR) are described and considered in relation to PPARs activation.
authors.affiliation: Swiss Institute of Bioinformatics (SIB), Quartier Sorge, Batiment Genopode, CH-1015 Lausanne, Switzerland.
authors.forename: Vincent
authors.initials: V
authors.lastname: Zoete
authors.forename: Aurelien
authors.initials: A
authors.lastname: Grosdidier
authors.forename: Olivier
authors.initials: O
authors.lastname: Michielin
mesh_terms: D000818:Animals; D006801:Humans; D008024:Ligands; D008958:Models, Molecular; D047493:PPAR alpha / Q000737:chemistry / Q000502:physiology; D047492:Peroxisome Proliferator-Activated Receptors / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D011487:Protein Conformation; D013379:Substrate Specificity
chemical_list: D008024:Ligands; D047493:PPAR alpha; D047492:Peroxisome Proliferator-Activated Receptors