FIG 8.

ATM kinase is also required for DFO-induced reactivation of EBV. (A) AGS-Akata cells grown in 10-cm dishes were incubated for 24 h with or without 10 μM KU-55933, an ATM inhibitor, prior to incubation as well with 200 μM DFO (lanes 2 and 6) or PBS (-; lanes 1 and 5) or transfection with 1.0 μg/dish of pcDNA3-BRLF1 (lanes 3 and 7) or pcDNA3FLAG-BLIMP1 (lanes 4 and 8). Twenty-four hours later, whole-cell extracts were prepared and processed for immunoblot analysis for the indicated proteins. The data shown are representative of those from three independent experiments. (B) ATM kinase is also required for synergistic reactivation of EBV by nutlin-3 plus DFO. AGS-Akata cells were incubated for 24 h with or without 10 μM KU-55933. Concurrently, the cells were incubated with 1.0 μM nutlin-3 where indicated. Afterward, 200 μM DFO or DMSO was added, and incubation was continued for an additional 24 h prior to harvesting and processing for immunoblot analysis.