FIG 6.
HRE is required for efficient p53 binding to Zp. (A) Schematic showing the sequence of the nt −102 to nt −59 region of Zp indicating some known cis-acting elements and the base pair substitution mutants in these elements used here. (B) Mutation of the Zp HRE is sufficient to prevent reactivation of EBV by DFO. Immunoblots show the relative levels of the indicated proteins following incubation of AGS-B95.8(WT) versus AGS-B95.8(HREm) cells with 200 μM DFO (+) or its diluent PBS (−) for 24 h. (C) Immunoblots showing that EBV reactivates to similar levels in these two cell lines when incubated for 48 h with a different inducer, TPA (20 ng/ml) plus valproate (1 mM). (D) Quantitative PCR analysis of chromatin obtained from these two cell lines treated with DFO as described for panel B and processed as described in the legend to Fig. 5. Data shown are means ± SEMs of CT values from two independent experiments performed in triplicate.