Molecular cloning and expression of human prostacyclin synthase.

The cDNA for human prostacyclin synthase was cloned by polymerase chain reaction using poly(A)+ RNA from human aortic endothelial cells according to the partial nucleotide sequence of prostacyclin synthase gene. The cloned cDNA with a size of 1977 base pairs contained a 1500 base pairs open reading frame which encoded a 500 amino acid protein sharing an 88% identity with bovine prostacyclin synthase. RNA blot analysis indicated that the size of major prostacyclin synthase mRNA of human aortic endothelial cells was approximately 6 kilobases and that its mRNA level was increased by interleukin 1 or interleukin 6 treatment. Moreover, tissue distribution study demonstrated that prostacyclin synthase mRNA is widely expressed in human tissues and is particularly abundant in ovary, heart, skeletal muscle, lung, and prostate. These results suggest a variety of physiological roles of prostacyclin in addition to the implications in the cardiovascular system.