MAPPING STUDIES OF 2 G-PROTEIN-COUPLED RECEPTOR GENES - AN AMINO-ACIDDIFFERENCE MAY CONFER A FUNCTIONAL VARIATION BETWEEN A HUMAN AND RODENT RECEPTOR

We recently isolated two orphan human G protein-coupled receptor genes designated GPR1 and GPR6. The gene GPR1 was shown to be transcribed a bundantly but only in the hippocampus. Here we report the cloning of t he rat GPR1 gene and report the absence of expression in hippocampus, demonstrating a functional variation for this receptor in these two sp ecies. The evolutionary history of an important sequence difference in the gene GPR1 in primate and rodent species has been examined. In con trast extensive mapping of gene GPR6 mRNA in rat brain was in keeping with the described distribution in human brain. (C) 1994 Academic Pres s, Inc.