Figure 7.

BMI1 knockdown inhibits DSB repair and sensitizes cells to IR. (A) The recruitment of BMI1 in H2AX WT and H2AX KO cells. Cells were microirradiated, allowed to recover for 5 min, and stained with the indicated antibodies. Bar, 5 µm. (B) BMI1 WT, BMI1 KO, and BMI1 KO cells reconstituted with WT BMI1 were either left untreated or exposed to 30 nM of CLM. The initial DNA damage levels and levels remaining at 1 h and 5 h at 37°C were measured with CFGE. (C) Survival curve of U2OS cells transfected with either control shRNA or a BMI1 shRNA. Cells were transfected with the indicated shRNA for 24 h, plated at low density, and exposed to the indicated doses of IR. The experiment was performed in triplicate. Error bars represent standard error from two independent experiments (n = 6).