Figure 4. The inhibition of binding between DNA-PKcs and Ku-complexes by BPA.

(A) M059K cells extracts were pre-incubated with the indicated concentrations of BPA and, thereafter, with DNA-immobilized beads or control beads. Bound proteins were eluted with SDS sample buffer and detected by immunoblotting. (B) (C) FLAG-Ku80 (B, bottom and C) or FLAG-Ku70 (B, top) was expressed in 293T cells incubated with 300 μM BPA and then irradiated with γ-rays (B) or UV (C). Cell lysates were immunoprecipitated using anti-FLAG agarose beads and immunoblotted with the indicated antibodies.