GATA-2 and HNF-3β Regulate the Human Alcohol Dehydrogenase 1A ( <i>ADH1A</i> ) Gene

In this paper, we have identified several distal cis-acting elements that contribute to the regulation and tissue- specificity of ADH1A, which encodes an alcohol dehydrogenase (ADH) that metabolizes ethanol. A negative element from bp -1873 to -1558, relative to the translational start site, decreased transcriptional activity to 52% in H4IIE-C3 cells and 70% in CV-1 cells. A positive element from bp -2459 to -2173 increased transcriptional activity twofold in H4IIE-C3 cells and 1.7-fold in CV-1 cells. Gel mobility shift and supershift assays demonstrated that GATA-2 bound a region within this positive element. A tissue-specific regulatory element from bp -6380 to -5403 increased transcription twofold in H4IIE-C3 cells while decreasing transcription to 86% in CV-1 cells. Within this tissue-specific fragment, the region from bp -5668 to -5403 increased transcription 1.7-fold in H4IIE-C3 cells and 1.3-fold in CV-1 cells. Hepatocyte nuclear factor-3beta (HNF- 3beta) bound a region of the tissue-specific element in CV-1 cells, but not in H4IIE-C3 cells. Positive regulation of the ADH1A gene may be influenced by GATA-2 binding, while differences in HNF-3beta binding in cells/tissues may contribute to tissue specificity.