Cloning and genetic characterization of an evolutionarily conserved human olfactory receptor that is differentially expressed across species

We have cloned the full-length cDNA and genomic region of a human prostate specific G-protein coupled receptor with properties characteristic of an ol factory receptor. A partial cDNA sequence of this gene, called PSGR, was re cently cloned. The gene contains two exons and one intron of 14.9 kb in its 5' untranslated region, and was mapped to human chromosome 11p15.2. A clus ter of transcription initiation sites for the 2.8 kb PSGR mRNA was identifi ed. Cloning of the homologous gene from the mouse revealed 93% amino acid h omology between the human and mouse or rat (previously cloned as RA1c) prot eins, and 99% identity between the rat and mouse homologs. Although norther n analysis indicated expression of the human PSGR homolog was prostate spec ific, its mRNA could also be detected in the olfactory zone and the medulla oblongata of the human brain. In the mouse, the PSGR, gene is predominantl y expressed in the brain and colon. In the rat, the PSGR homolog is express ed in the liver in addition to the brain. These data add to the growing bod y of evidence suggesting that olfactory receptors may have functional roles in tissues other than the olfactory organ, and further, suggest that these functions may vary across species. (C) 2001 Elsevier Science B.V. All righ ts reserved.