Figure 2

SPRR2A dislocates p53 from its DNA binding element, reducing target gene transcription. (A) Sequence for the biotinylated double-stranded DNA probes that mimic the wild type and mutational p53 response elements (RE). (B) DNA pull-down assay showing that SPRR2A expression reduces p53 binding to the p53-RE when compared to its corresponding control. That is, p53 binding strengths are as follows: transfection with p53 > p53/SPRR2A and transfection with p53/p300 > p53/p300/SPRR2A. (C) Luciferase assays of p21-RE and p53-RE from cells transfected with indicated vectors. For p53-RE reporter, we used wild type (WT) and mutational (MT) RE vectors. Again, SPRR2A expression reduced reporter activity when compared to the corresponding control transfection. (D) Western blot analysis showing that SPRR2A reduced p21 expression and acetylation of p300 and p53. WT, wild type; MT, mutation; *, p < 0.05; ** <0.01, *** < 0.001.