title: The Importance of Ligand-Receptor Conformational Pairs in Stabilization: Spotlight on the N/OFQ G Protein-Coupled Receptor.
abstract: Understanding the mechanism by which ligands affect receptor conformational equilibria is key in accelerating membrane protein structural biology. In the case of G protein-coupled receptors (GPCRs), we currently pursue a brute-force approach for identifying ligands that stabilize receptors and facilitate crystallogenesis. The nociceptin/orphanin FQ peptide receptor (NOP) is a member of the opioid receptor subfamily of GPCRs for which many structurally diverse ligands are available for screening. We observed that antagonist potency is correlated with a ligand's ability to induce receptor stability (Tm) and crystallogenesis. Using this screening strategy, we solved two structures of NOP in complex with top candidate ligands SB-612111 and C-35. Docking studies indicate that while potent, stabilizing antagonists strongly favor a single binding orientation, less potent ligands can adopt multiple binding modes, contributing to their low Tm values. These results suggest a mechanism for ligand-aided crystallogenesis whereby potent antagonists stabilize a single ligand-receptor conformational pair.
authors.affiliation: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Miller
authors.affiliation: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Aaron A
authors.initials: AA
authors.lastname: Thompson
authors.affiliation: Department of Chemical and Pharmaceutical Sciences and LTTA (Laboratorio per le Tecnologie delle Terapie Avanzate), University of Ferrara, 44121 Ferrara, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Trapella
authors.affiliation: Department of Chemical and Pharmaceutical Sciences and LTTA (Laboratorio per le Tecnologie delle Terapie Avanzate), University of Ferrara, 44121 Ferrara, Italy.
authors.forename: Remo
authors.initials: R
authors.lastname: Guerrini
authors.affiliation: Department of Medical Sciences, Section of Pharmacology and National Institute of Neuroscience, University of Ferrara, 44121 Ferrara, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Malfacini
authors.affiliation: Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Nilkanth
authors.initials: N
authors.lastname: Patel
authors.affiliation: Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Gye Won
authors.initials: GW
authors.lastname: Han
authors.affiliation: Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Vadim
authors.initials: V
authors.lastname: Cherezov
authors.affiliation: Department of Medical Sciences, Section of Pharmacology and National Institute of Neuroscience, University of Ferrara, 44121 Ferrara, Italy.
authors.forename: Girolamo
authors.initials: G
authors.lastname: Caló
authors.affiliation: Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Vsevolod
authors.initials: V
authors.lastname: Katritch
authors.affiliation: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Chemistry, Bridge Institute, University of Southern California, Los Angeles, CA 90089, USA; Department of Biological Sciences, Bridge Institute, University of Southern California, Los Angeles, CA 90089, USA. Electronic address: stevens@usc.edu.
authors.forename: Raymond C
authors.initials: RC
authors.lastname: Stevens
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D003508:Cycloheptanes / Q000494:pharmacology; D057809:HEK293 Cells; D006801:Humans; D008024:Ligands; D062105:Molecular Docking Simulation; D008969:Molecular Sequence Data; D010880:Piperidines / Q000494:pharmacology; D011485:Protein Binding; D011957:Receptors, Opioid / Q000737:chemistry* / Q000378:metabolism; D000094942:Nociceptin Receptor
chemical_list: D003508:Cycloheptanes; D008024:Ligands; D010880:Piperidines; D011957:Receptors, Opioid; C482404:cis-1-methyl-7-((4-(2,6-dichlorophenyl)piperidin-1-yl)methyl)-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-ol; D000094942:Nociceptin Receptor; C000722283:OPRL1 protein, human
keywords: BRET; G protein-coupled receptor; GPCR; N/OFQ; NOP; Nociceptin/orphanin FQ peptide receptor; ORL-1; lipidic cubic phase; membrane protein; opioid receptor; receptor-ligand conformational pair