Fig. 4.

The p53-related p63γ and p73β proteins can cooperate with ERα to transactivate canonical p53 REs in the FLT1 promoter. A derivative of the 1-kb FLT1 promoter construct containing the p53REs from AIP or p21 genes was cotransfected into SaOS2 cells in the presence of p73β and p63γ alone or in combination with an ERα expression vector. Luciferase activity was measured 48 h posttransfection. Empty + represents a vector (pCMV-Neo) used to keep constant the amount of total DNA transfected. Presented is the average-fold luciferase induction relative to the empty reporter vector ± SD (n = 3).