Molecular Cloning of cDNA for Human Epinephrine Synthesizing Enzyme, Phenylethanolamine N-Methyltransferase(PNMT)

Abstract

An oligo(dT)-primed eDNA was constructed from poly(A)+ -containinq RNA from human adrenal tissues. The eDNA was inserted into the EcoRl site of ). gtlO phage and the human library was screened for clones containing cDNAs coding for human phenylethanolamine N- methyl transferase(PNMT). Approximately 1.5 X 106 recombinant phage plaques were transferred to nitrocellulose filters and a eDNA clone was isolated and identified from the ). gtlO DNA by digestion with EcoRl and was found to .be approximately 1150 base pairs in length containing one internal EcoRl site. Northern blot analysis showed that the eDNA strongly hybridized to an RNA species of approximately 1.1 kb, a size appropriate for an mRNA coding for PNMT. The human adrenal mRNA selected by the eDNA codes for a 31k dalton protein. This is the first report of the cloning of eDNA for human epinephrine synthesizing enzyme, PNMT.