Cloning and characterization of a novel orphan G-protein-coupled receptor localized to human chromosome 2p16

We report the identification and characterisation of a novel human orphan G -protein-coupled receptor (GPR) which maps to chromosome 2p16. We have dete rmined the full-length coding sequence and genomic structure of a gene corr esponding to the anonymous expressed sequenced tag, WI-31133. This gene enc odes a novel protein that is 540 amino acids in length. Protein sequence an alysis predicts the presence of seven transmembrane domains, a characterist ic feature of GPRs. In situ, hybridisation to human retina and Northern blo t analysis of human retinal pigment epithelium (RPE) showed localisation of this transcript to the RPE and cells surrounding retinal arterioles; In co ntrast, the transcript was localised to the photoreceptor inner segments an d the outer plexiform layer in mouse sections. Northern blot analysis demon strated a 7 kb transcript highly expressed in the brain. No mutations were identified during a screen of patients suffering from Doyne's honeycomb ret inal dystrophy (DHRD), an inherited retinal degeneration which maps to chro mosome 2p16. (C) 1999 Academic Press.