UBIQUITOUS TRANSCRIPTION FACTORS NF1 AND SP1 ARE INVOLVED IN THE ANDROGEN ACTIVATION OF THE MOUSE VAS-DEFERENS PROTEIN PROMOTER

Transcription of the mouse vas deferens protein (MVDP) gene is stimula ted by androgens and we have previously shown that in a 162 bp fragmen t, located at position -121 to +41, a TGAAGTtccTGTTCT sequence functio ns as an androgen-dependent enhancer. To determine which factors are i nvolved in the hormonally regulated MVDP gene transcription, we have u sed DNase I footprinting and band-shift assays to examine in vitro bin ding of proteins to the enhancer and promoter sequences and have deter mined the functional significance of the recognized DNA sequences in t ransient transfection assays. Studies using recombinant proteins such as the DNA binding domain of the androgen receptor (AR-DBD) and Sp1, a nd crude cellular extracts from T47D and vas deferens epithelial cells (VDEC) showed that in addition to AR-DBD, the transcriptional activat ors NF1 and Sp1 interact with the -121/+41 fragment in a specific mann er. Transient transfection assays revealed that site-directed mutation s in the NF1 and Sp1 binding elements strongly reduced (NF1) or abolis hed (Spl) androgen induced expression. The results demonstrate that th e -121/+41 sequence is a composite site for the androgen receptor medi ated transactivation of the MVDP gene. (C) 1997 Elsevier Science Irela nd Ltd.