STRUCTURAL ORGANIZATION AND CHROMOSOMAL ASSIGNMENT OF THE HUMAN PROSTACYCLIN RECEPTOR GENE

Prostacyclin receptor is a member of the prostanoid receptor family in the G protein-coupled receptor superfamily with seven transmembrane d omains, We report here the isolation and structural organization of th e human prostacyclin receptor gene. Southern blot analysis demonstrate d a single copy of the human prostacyclin receptor gene in the human g enome, The human prostacyclin receptor gene spanned approximately 7.0 kb and was composed of three exons separated by two introns. The first intron occurred in the 5'-untranslated region, 13 bp upstream to the ATG start codon. The second intron was located at the end of the sixth transmembrane domain, thereby separating it from the downstream codin g region and the 3'-untranslated region. By primer extension analysis, the transcription initiation sites were mapped 870-872 bp upstream to the ATG start codon. The 1.2-kb human prostacyclin receptor 5'-flanki ng region lacked conventional TATA and CCAAT boxes, but it contained s everal cis-acting regulatory elements including an inverted CCAAT box (Y box) and two copies of SP-1 binding sites. Using human-rodent somat ic hybrid cell DNA, the human prostacyclin receptor gene was assigned to human chromosome 19. The present study helps establish the genetic basis for prostacyclin receptor research and provides further insight into the molecular mechanisms underlying the prostanoid receptor famil y. (C) 1995 Academic Press, Inc.