Molecular Cloning and Characterization of the Rat Ovarian 20α-Hydroxysteroid Dehydrogenase Gene

• Published in: Biochemical and biophysical research communications 1998-08, Vol.249 (3), p.797-803
• Main Authors: Zhong, L., Ou, J., Barkai, U., Mao, J.F., Frasor, J., Gibori, G.
• Format: Article
• Language: English
• Subjects: 20-alpha-Hydroxysteroid Dehydrogenase; 20-Hydroxysteroid Dehydrogenases - genetics; Animals; Base Sequence; Cell Line; Cloning, Molecular; Colforsin - pharmacology; DNA Primers - genetics; DNA, Complementary - genetics; Exons; Female; Gene Expression Regulation, Enzymologic - drug effects; Introns; Molecular Sequence Data; Ovary - enzymology; Polymerase Chain Reaction; Promoter Regions, Genetic; Rats; Sequence Deletion; TATA Box; Transfection
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.1998.9229

The rat 20α-hydroxysteroid dehydrogenase (20α-HSD) is an enzyme responsible for the catabolism of progesterone to the inactive 20α-hydroxyprogesterone. We have previously shown that the expression of this enzyme is not regulated by post-translational modification, but at the level of transcription. In this study we have established that the 20α-HSD gene contains nine exons and have isolated a 2.5 kb promoter region. The transcription start site was identified and a TATA box was found. 5′ deletions of this promoter significantly decreased basal promoter activity. Treatment with forskolin led to a dose dependent inhibition of the 2.5kb-20α-HSD-luciferase construct. Computer analysis identified one CRE, two Nur77 response elements, two putative AP1 sites and one progesterone response element half-site. In summary, we have identified and partially characterized the promoter region of the rat ovarian 20α-HSD and demonstrated that the regulatory elements for 20α-HSD are present within a 2.5 kb 5′ flanking region of the gene.