IUPHAR/BPS Guide to Pharmacology CITE https://doi.org/10.2218/gtopdb/F16/2019.4 Class A Orphans (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database Stephen P.H. Alexander1, Jim Battey2, Helen E. Benson3, Richard V. Benya4, Tom I. Bonner5, Anthony P. Davenport6, Satoru Eguchi7, Anthony Harmar3, Nick Holliday1, Robert T. Jensen2, Sadashiva Karnik8, Evi Kostenis9, Wen Chiy Liew3, Amy E. Monaghan3, Chido Mpamhanga10, Richard Neubig11, Adam J. Pawson3, Jean-Philippe Pin12, Joanna L. Sharman3, Michael Spedding13, Eliot Spindel14, Leigh Stoddart15, Laura Storjohann16, Walter G. Thomas17, Kalyan Tirupula8 and Patrick Vanderheyden18 1. University of Nottingham, UK 2. National Institutes of Health, USA 3. University of Edinburgh, UK 4. University of Illinois at Chicago, USA 5. National Institute of Mental Health, USA 6. University of Cambridge, UK 7. Temple University, USA 8. Cleveland Clinic Lerner Research Institute, USA 9. University of Bonn, Germany 10. LifeArc, UK 11. Michigan State University, USA 12. Université de Montpellier, France 13. Spedding Research Solutions SARL, France 14. Oregon Health & Science University, USA 15. University of Glasgow, UK 16. University of Utah, USA 17. University of Queensland, Australia 18. Vrije Universiteit Brussel, Belgium Abstract Table 1 lists a number of putative GPCRs identified by NC-IUPHAR [191], 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 [148]. 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 GPR3 GPR4 GPR6 GPR12 GPR15 GPR17 GPR20 GPR22 GPR26 GPR31 GPR34 GPR35 GPR37 GPR39 GPR50 GPR63 GRP65 GPR68 GPR75 GPR84 GPR87 GPR88 GPR132 GPR149 GPR161 GPR183 LGR4 LGR5 1 LGR6 MAS1 MRGPRD MRGPRX1 MRGPRX2 P2RY10 TAAR2 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). Contents This is a citation summary for Class A Orphans in the Guide to Pharmacology database (GtoPdb). It exists purely as an adjunct to the database to facilitate the recognition of citations to and from the database by citation analyzers. Readers will almost certainly want to visit the relevant sections of the database which are given here under database links. GtoPdb is an expert-driven guide to pharmacological targets and the substances that act on them. GtoPdb is a reference work which is most usefully represented as an on-line database. As in any publication this work should be appropriately cited, and the papers it cites should also be recognized. This document provides a citation for the relevant parts of the database, and also provides a reference list for the research cited by those parts. Please note that the database version for the citations given in GtoPdb are to the most recent preceding version in which the family or its subfamilies and targets were substantially changed. The links below are to the current version. If you need to consult the cited version, rather than the most recent version, please contact the GtoPdb curators. Database links Class A Orphans http://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=16 Introduction to Class A Orphans http://www.guidetopharmacology.org/GRAC/FamilyIntroductionForward?familyId=16 Receptors BB3 receptor http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=40 GPR3 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=83 GPR4 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=84 GPR6 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=85 GPR42 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=228 GPR12 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=86 GPR15 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=87 GPR17 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=88 GPR18 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=89 GPR19 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=90 GPR20 2 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=91 GPR21 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=92 GPR22 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=93 GPR25 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=95 GPR26 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=96 GPR27 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=97 GPR31 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=98 GPR32 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=99 GPR33 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=100 GPR34 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=101 GPR35 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=102 GPR37 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=103 GPR37L1 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=104 GPR39 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=105 GPR45 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=106 GPR50 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=107 GPR52 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=108 GPR55 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=109 GPR61 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=110 GPR62 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=111 GPR63 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=112 GPR65 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=113 GPR68 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=114 GPR75 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=115 GPR78 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=116 GPR79 3 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=117 GPR82 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=118 GPR83 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=119 GPR84 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=120 GPR85 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=121 GPR87 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=122 GPR88 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=123 GPR101 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=125 GPR119 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=126 GPR132 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=128 GPR135 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=129 GPR139 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=130 GPR141 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=131 GPR142 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=132 GPR146 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=133 GPR148 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=134 GPR149 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=135 GPR150 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=136 GPR151 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=137 GPR152 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=138 GPR153 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=139 GPR160 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=140 GPR161 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=141 GPR162 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=142 GPR171 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=143 GPR173 4 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=144 GPR174 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=145 GPR176 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=637 GPR182 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=146 GPR183 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=81 LGR4 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=147 LGR5 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=148 LGR6 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=149 MAS1 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=150 MAS1L http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=151 MRGPRD http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=152 MRGPRE http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=153 MRGPRF http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=154 MRGPRG http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=155 MRGPRX1 http://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=156