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 clones, cUT, was found to contain the complete coding sequence of a new gene 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 acids is identical to the N-terminus of the testosterone 6 beta-hydroxylase, 6 beta-2 (Nagata, K., Gonzalez, F.J., Yamazoe, Y. and Kato, R. (1990) J. Biochem. 107, 718-725). Northern blots show the presence of cUT mRNA in livers of adult female and male rats. The transcription of the new gene is enhanced in either sex by pregnenolone-alpha-carbonitrile, dexamethasone, phenobarbital, and triacetyloleandomycin, known inducers of CYP3A gene expression.