DBP BINDS TO THE PROXIMAL PROMOTER AND REGULATES LIVER-SPECIFIC EXPRESSION OF THE HUMAN ANGIOTENSINOGEN GENE

Angiotensinogen is the glycoprotein precursor of one of the most poten t vasoactive hormones, angiotensin-II. It has been shown recently that an ATF like element (ALE) located between bases -102 and -87 of the h uman angiotensinogen gene plays an important role in liver specific ex pression of this gene and binds to CREB/ATF family of transcription fa ctors and a novel factor (ALF). We show here that this sequence binds to the liver enriched transcription factor DBP and cotransfection of e xpression vector CMV-DBP increases the expression of reporter construc ts containing this sequence. In addition, we show that transcription f actor C/EBP-delta binds to this sequence and an expression vector cont aining C/EBP-delta coding region increases the expression of reporter constructs containing this sequence. Since DBP is involved in circadia n rhythm, our studies suggest that this sequence may be involved in ci rcadian expression of the human angiotensinogen gene. (C) 1998 Academi c Press.