| Title: | Molecular cloning and characterization of two novel retinoic acid-inducible orphan G-protein-coupled receptors (GPRC5B and GPRC5C) |
| Author(s): | Robbins MJ; Michalovich D; Hill J; Calver AR; Medhurst AD; Gloger I; Sims M; Middlemiss DN; Pangalos MN; |
| Address: | "Neuroscience Research, SmithKline Beecham, Harlow, Essex, United Kingdom" |
| ISSN/ISBN: | 0888-7543 (Print) 0888-7543 (Linking) |
| Abstract: | "Using homology searching of public databases with a metabotropic glutamate receptor sequence from Caenorhabditis elegans, two novel protein sequences (named RAIG-2 (HGMW-approved symbol GPRC5B) and RAIG-3 (HGMW-approved symbol GPRC5C) were identified containing seven putative transmembrane domains characteristic of G-protein-coupled receptors (GPCRs). RAIG-2 and RAIG-3 encode open reading frames of 403 and 442 amino acid polypeptides, respectively, and show 58% similarity to the recently identified retinoic acid-inducible gene-1 (RAIG-1, HGMW-approved symbol RAI3). Analysis of the three protein sequences places them within the type 3 GPCR family, which includes metabotropic glutamate receptors, GABA(B) receptors, calcium-sensing receptors, and pheromone receptors. However, in contrast to other type 3 GPCRs, RAIG-1, RAIG-2, and RAIG-3 have only short N-terminal domains. RAIG-2 and RAIG-3 cDNA sequences were cloned into the mammalian expression vector pcDNA3 with c-myc or HA epitope tags inserted at their N-termini, respectively. Transient transfection experiments in HEK239T cells using these constructs demonstrated RAIG-2 and RAIG-3 expression at the cell surface. Distribution profiles of mRNA expression obtained by semiquantitative Taq-Man PCR analysis showed RAIG-2 to be predominantly expressed in human brain areas and RAIG-3 to be predominantly expressed in peripheral tissues. In addition, expression of RAIG-2 and RAIG-3 mRNA was increased following treatment with all-trans-retinoic acid in a manner similar to that previously described for RAIG-1. Finally, RAIG-2 was mapped to chromosome 16p12 (D16S405-D16S3045) and RAIG-3 to chromosome 17q25 (D17S1352-D17S785). These results suggest that RAIG-1, RAIG-2, and RAIG-3 represent a novel family of retinoic acid-inducible receptors, most closely related to the type 3 GPCR subfamily, and provide further evidence for a linkage between retinoic acid and G-protein-coupled receptor signal transduction pathways" |
| Keywords: | "Amino Acid Sequence Base Sequence Brain/physiology Chromosomes, Human, Pair 16 Chromosomes, Human, Pair 17 Cloning, Molecular DNA Primers/chemistry GTP-Binding Proteins/genetics/*metabolism Gene Expression Regulation Humans Molecular Sequence Data Multige;neuroscience;" |
| Notes: | "MedlineRobbins, M J Michalovich, D Hill, J Calver, A R Medhurst, A D Gloger, I Sims, M Middlemiss, D N Pangalos, M N eng 2000/08/17 Genomics. 2000 Jul 1; 67(1):8-18. doi: 10.1006/geno.2000.6226" |
