title: Screening β-arrestin recruitment for the identification of natural ligands for orphan G-protein-coupled receptors.
abstract: A variety of G-protein-coupled receptor (GPCR) screening technologies have successfully partnered a number of GPCRs with their cognate ligands. GPCR-mediated β-arrestin recruitment is now recognized as a distinct intracellular signaling pathway, and ligand-receptor interactions may show a bias toward β-arrestin over classical GPCR signaling pathways. We hypothesized that the failure to identify native ligands for the remaining orphan GPCRs may be a consequence of biased β-arrestin signaling. To investigate this, we assembled 10 500 candidate ligands and screened 82 GPCRs using PathHunter β-arrestin recruitment technology. High-quality screening assays were validated by the inclusion of liganded receptors and the detection and confirmation of these established ligand-receptor pairings. We describe a candidate endogenous orphan GPCR ligand and a number of novel surrogate ligands. However, for the majority of orphan receptors studied, measurement of β-arrestin recruitment did not lead to the identification of cognate ligands from our screening sets. β-Arrestin recruitment represents a robust GPCR screening technology, and ligand-biased signaling is emerging as a therapeutically exploitable feature of GPCR biology. The identification of cognate ligands for the orphan GPCRs and the extent to which receptors may exist to preferentially signal through β-arrestin in response to their native ligand remain to be determined.
authors: Medical Research Council Technology, Centre for Therapeutic Discovery, London, UK. craig.southern@tech.mrc.ac.uk
authors: Craig
authors: C
authors: Southern
authors: Jennifer M
authors: JM
authors: Cook
authors: Zaynab
authors: Z
authors: Neetoo-Isseljee
authors: Debra L
authors: DL
authors: Taylor
authors: Catherine A
authors: CA
authors: Kettleborough
authors: Andy
authors: A
authors: Merritt
authors: Daniel L
authors: DL
authors: Bassoni
authors: William J
authors: WJ
authors: Raab
authors: Elizabeth
authors: E
authors: Quinn
authors: Tom S
authors: TS
authors: Wehrman
authors: Anthony P
authors: AP
authors: Davenport
authors: Andrew J
authors: AJ
authors: Brown
authors: Andrew
authors: A
authors: Green
authors: Mark J
authors: MJ
authors: Wigglesworth
authors: Steve
authors: S
authors: Rees
mesh_terms: D000818:Animals; D019390:Arrestins / Q000378:metabolism*; D016466:CHO Cells; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus; D055808:Drug Discovery / Q000379:methods; D057809:HEK293 Cells; D057166:High-Throughput Screening Assays / Q000379:methods*; D006801:Humans; D008024:Ligands; D011485:Protein Binding / Q000502:physiology; D043562:Receptors, G-Protein-Coupled / Q000819:agonists* / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D054852:Small Molecule Libraries / Q000032:analysis; D000071557:beta-Arrestins
chemical_list: D019390:Arrestins; C111379:GPR35 protein, human; D008024:Ligands; D043562:Receptors, G-Protein-Coupled; D054852:Small Molecule Libraries; D000071557:beta-Arrestins
keywords: natural ligand; orphan G-protein–coupled receptor; β-arrestin recruitment