MOLECULAR-CLONING OF 2 CANNABINOID TYPE 1-LIKE RECEPTOR GENES FROM THE PUFFER FISH FUGU RUBRIPES

The puffer fish, Fugu rubripes (Fugu), has been proposed as a model ve rtebrate genome. We have characterized two putative G-protein-coupled receptor encoding genes, FCB1A and FCB1B, obtained by degenerate PCR a nd low-stringency hybridization of a Fugu genomic library, These two g enes show high homology to the human cannabinoid receptor type 1 (HCB1 ), but very low homology to the type 2 receptor. The amino acid sequen ces of the FCB1A and FCB1B genes are 66.2% identical, and the homology of each gene to HCB1 is 72.2 and 59.0%, respectively. The transcripts of both the FCB1A and the FCB1B receptors are abundant in the brain. No type 2 receptor could be cloned from Fugu, These data suggest that although two cannabinoid receptor-like genes are found in the puffer f ish, both show similarity to the type 1 receptor found in human. (C) 1 996 Academic Press, Inc.