G Protein Coupled Receptor 42 (GPR42)

The physiologic responses to galanin (GAL) are mediated through specific membrane receptors called GALRs, which are members of the G protein-coupled receptor (GPCR) family. Sawzdargo et al. (1997) amplified human genomic DNA using PCR with degenerate primers based on conserved sequences of human and rat GALR1 and rat Galr2. One product contained a segment showing 100% homology to a portion of the 3-prime region of the human CD22 gene. The authors identified a PAC clone in the sequence databases that overlaps this region and contains a novel putative GPCR gene, GPR42. This intronless gene is located within a possible polymorphic insert. The deduced 346-amino acid GPR42 protein has 7 predicted transmembrane regions. It is 98% identical to GPR41 but shares little similarity with GALRs.