A NOVEL CYP3 GENE FROM FEMALE RATS

A cDNA library constructed from adult female Sprague Dawley rat liver was screened with polyclonal anti CYP3A-IgG. One of the positive clone s, cUT, was found to contain the complete coding sequence of a new gen e more similar to hamster gene CYP3A10 (cDNA: 85%, deduced amino acid sequence: 79%) than to the known rat CYP3A genes (cDNA: 75-76%, amino acid sequences: 66-69%). The deduced sequence of the first 28 amino ac ids is identical to the N-terminus of the testosterone 6 beta-hydroxyl ase, 6 beta-2 (Nagata, K., Gonzalez, F.J., Yamazoe, Y. and Kato, R. (1 990) J. Biochem. 107, 718-725). Northern blots show the presence of cU T mRNA in livers of adult female and male rats. The transcription of t he new gene is enhanced in either sex by pregnenolone-alpha-carbonitri le, dexamethasone, phenobarbital, and triacetyloleandomycin, known ind ucers of CYP3A gene expression.