Structure and characterization of the gene encoding a mouse kappa3-related opioid receptor

A genomic clone comprising the entire cDNA sequence encoding a mouse kappa3-related opioid receptor (KOR-3) was isolated by screening a mouse genomic library with a radiolabeled mouse KOR-3 cDNA probe. Sequence analysis of the genomic clone indicates that the KOR-3 gene contains five exons separated by four introns. The transcription start point (tsp) of KOR-3 was mapped by primer extension analysis of RNAs synthesized either in vivo or in vitro. A TATA-box and several potential regulatory elements, including five GRE sites, four NF-E1 binding sites and one MRE site, are present in the 2 kb of 5'-flanking region. A putative poly(A) signal (AATAAA) is found in the 3'-flanking region.