ISOLATION OF 3 NOVEL HUMAN GENES ENCODING G-PROTEIN-COUPLED RECEPTORS

We have cloned and mapped the chromosomal location of three novel huma n genes encoding G protein-coupled receptors that we have named GPR6, GPR5, and GPR4. The entire coding region for each of these genes was c ontained on single exons, Gene GPR6 encoded a receptor that shared clo sest identity (71% in the transmembrane regions) with the human orphan receptor GPR3 and was localized to chromosome 6 (q21-q22.1). Northern blot analysis revealed that GPR6 transcripts were abundant in the hum an putamen and to a lesser extent in the frontal cortex, hippocampus, and hypothalamus. Gene GPR5 encoded a receptor that most closely resem bled the orphan receptor RBS11 (48% in the transmembrane regions) and the MIP 1 alpha/RANTES receptor (45% in the transmembrane regions) and was localized to chromosome 3 (p21.3-p21.1). Gene GPR4 shared identit y (40% in the transmembrane regions) with the human platelet-activatin g factor receptor and was localized to chromosome 19 (q13.2-q13.3).