TY - JOUR AU - Stephen P.H. Alexander AU - Jim Battey AU - Helen E. Benson AU - Richard V. Benya AU - Tom I. Bonner AU - Anthony P. Davenport AU - Khuraijam Dhanachandra Singh AU - Satoru Eguchi AU - Anthony Harmar AU - Nick Holliday AU - Robert T. Jensen AU - Sadashiva Karnik AU - Evi Kostenis AU - Wen Chiy Liew AU - Amy E. Monaghan AU - Chido Mpamhanga AU - Richard Neubig AU - Adam J Pawson AU - Jean-Philippe Pin AU - Joanna L. Sharman AU - Michael Spedding AU - Eliot Spindel AU - Leigh Stoddart AU - Laura Storjohann AU - Walter G. Thomas AU - Kalyan Tirupula AU - Patrick Vanderheyden PY - 2022/10/13 Y2 - 2024/03/29 TI - Class A Orphans in GtoPdb v.2022.3 JF - IUPHAR/BPS Guide to Pharmacology CITE JA - GtoPdb CITE VL - 2022 IS - 3 SE - Summaries DO - 10.2218/gtopdb/F16/2022.3 UR - http://journals.ed.ac.uk/gtopdb-cite/article/view/7537 AB - Table 1 lists a number of putative GPCRs identified by NC-IUPHAR [161], for which preliminary evidence for an endogenous ligand has been published, or for which there exists a potential link to a disease, or disorder. These GPCRs have recently been reviewed in detail [121]. The GPCRs in Table 1 are all Class A, rhodopsin-like GPCRs. Class A orphan GPCRs not listed in Table 1 are putative GPCRs with as-yet unidentified endogenous ligands.Table 1: Class A orphan GPCRs with putative endogenous ligands GPR3GPR4GPR6GPR12GPR15GPR17GPR20 GPR22GPR26GPR31GPR34GPR35GPR37GPR39 GPR50GPR63GPR65GPR68GPR75GPR84GPR87 GPR88GPR132GPR149GPR161GPR183LGR4LGR5 LGR6MAS1MRGPRDMRGPRX1MRGPRX2P2RY10TAAR2 In addition the orphan receptors GPR18, GPR55 and GPR119 which are reported to respond to endogenous agents analogous to the endogenous cannabinoid ligands have been grouped together (GPR18, GPR55 and GPR119). ER -