Figure 5. CycG2 cooperates with B′γ in dephosphorylation of γH2AX. (A) U2OS cells treated with B′γ siRNA (siB′γ) or control siRNA (GL2) were exposed to IR and fixed at various time points. Representative images of cells stained with an anti-γH2AX antibody and Hoechst 33258 are shown. Bar = 10 μm. (B) The graph indicates the percentage of cells containing γH2AX foci at various time points following IR. Data were calculated as described in the legend to Figure 3F. (C) Wild-type MEFs and Ccng2^−/− MEFs treated with siB′γ or GL2 were exposed to IR and incubated for up to 24 h (only the images for NT, 1 and 24 h are shown here). Representative images of cells stained with an anti-γH2AX antibody and Hoechst 33258 are shown. Bar = 10 μm. (D) The bar graph indicates the percentage of cells containing γH2AX foci at 24 h after IR. Data were calculated as described in the legend to Figure 3F. Values significantly different from GL2-treated or siB′γ-treated wild-type MEFs are indicated (*, **, ***, ****). *p = 0.0053, **p = 0.0017, ***p = 0.00056, ****p = 0.040 (Student’s t-test) Note: ns, non-significant. The error bars denote the SD.