Molecular cloning and functional analysis of the murine bax gene promoter

Bcl-2-associated X protein (Bax) is a proapoptotic protein and is suggested to have an important role in carcinogenesis. To investigate the mechanism of bar gene transcriptional regulation, we isolated and sequenced the genom ic DNA fragment of the 5' flanking region of the murine bur gene, and subcl oned its promoter region into a luciferase reporter construction. The murin e bur promoter is TATA-less, and the sequence is only partially homologous to that of the human bar promoter. Transient transfection into NIH 3T3 cell s using unidirectionally deleted promoters and mutants of Spl sites reveale d that two Spl sites were partially responsible for the basal activity. The murine bar promoter was not responsive to exogenous p53, suggesting that t he p53-responsive element may not exist in the region used in our current e xperiments. (C) 1999 Elsevier Science B.V. All rights reserved.