Multiple regulatory elements and binding proteins of the 5'-flanking region of the human estrogen-responsive finger protein (efp) gene

The efp, a member of the RING finger family, was previously identified as an estrogen responsive gene. Here, we characterized basal promoter of the human efp gene. Transcription initiation site was found at position -60 G relative to the site for translation initiation, and TATA motif was absent. Deletion and mutation analyses of the 5'-flanking region using MCF-7 breast cancer cells indicated that the sequences located at -137 to -72 had the promoter activity for which an E-box (CACGTG) element at -110 to -105 was essential. EMSA showed that USF-1 bound to the E-box and that a protein-DNA complex was formed at the positive regulatory region (-137 to -110). Moreover, a strong negative regulatory region was present in -235 to -174. These findings suggest that the human efp promoter is regulated by multiple elements and their interacting factors, and the E-box near the transcription initiation site is essential for the basal promoter activity. (C) 1997 Academic Press.