Cloning of a complete cDNA encoding human aromatase : Immunochemical identification and sequence analysis

A complete cDNA clone encoding a human aromatase was isolated from a human placental cDNA library in λgtll. An antibody to the polypeptide specified by the isolated clone was prepared, and Western blot analysis and antibody inhibition experiments of human placental aromatase activity confirmed the identification of the clone as aromatase cDNA. The isolated aromatase cDNA clone of 3030 bp with two unique EcoRI sites contained a 3′-noncoding region of 1397 bp, an open reading frame of 1509 bp encoding 503 amino acid residues, and a 5′-noncoding region of 124 bp. Analysis of the amino acid sequence of aromatase and comparison of aromatase with other forms of cytochrome P-450 indicated that this enzyme is a unique form of the cytochrome P-450 superfamily.