Figure 2

CK2 co-localizes with γ-H2AX to sites of DNA damage. A. Association between CK2α' and γ-H2AX was revealed by in situ PLA. Cells expressing or lacking CK2α' were left untreated or incubated with 0.5 μg/ml NCS for 1 hour before fixation and labeling with primary antibodies directed against the indicated proteins. Control, refers to cells transfected with si-CK2α' and stained with secondary antibodies. Cell nuclei were revealed by Hoechst staining. B. Quantification of the number of signals/cell as distinct fluorescent red spots was performed by computer-assisted image analysis as described in Experimental Procedures. Mean values +/- SD from three independent experiments are shown. *P < 0.0001 denotes statistically significant difference.