Cloning and characterisation of G protein-coupled receptor genes from a human genomic library.

摘要

omology screening has been used as an approach to clone novel genes belonging to the G-linked superfamily of receptor proteins. The method of homology screening has been applied to a human genomic library resulting in the successful isolation of six G-linked receptor genes. Three of these genes; HG 1-1A, HG 10-1 and HG 11-1, represent the previously cloned sequences of the dopamine D1 receptor, the serotonin S1A receptor and the serotonin S2 receptor respectively. Two of the remaining genes, termed HG 9-3 and HG 14-1, represent novel partial clones which show a high degree of sequence homology with other members of the G-linked receptor superfamily. Results of a Genbank search based on amino acid sequence showed a strong relation between the gene HG 9-3 and the family of odorant receptors while identifying the gene MG 14-1 as a possible amine receptor. The sixth clone, HG 9-2, has been characterised as a novel member of the somatostatin family of receptor proteins. The HG 9-2 clone, termed SSTR 3, shows 78% identity with the recently cloned rat SSTR 3 receptor. Northern blot analysis revealed an SSTR 3 mRNA species of