Figure 2.

HNF4α1 Activates Human p21 Promoter Activity

Transient transfection assay of HEK293 cells in 12-well plates with the indicated human p21 promoter constructs (0.5 μg) driving luciferase (Luc) expression. Shown is fold induction of samples with pMT7.HNF4α1 (0.5 μg) vs. pMT7 empty vector normalized to CMV.β-gal (0.2 μg). Results are means ± sd of triplicate samples from one representative experiment out of three independent experiments performed. *, Fold induction is significant at P < 0.05. Previously characterized p53 and proximal Sp1 sites and TATA box (10) are shown along with Sp1 sites in the distal region and two HNF4α binding sites predicted by TRANSFAC and HNF4 Motif finder (see supplemental Fig. S3 for the full promoter sequence).