Figure 1.

E2F Transcription and Active Protein Synthesis Are Required to Prevent RS-Induced DNA Damage

(A) Graph of mean chromatin-bound γH2AX intensity of single nuclei. Treatment and times are as shown for RPE1 cells. p, significant differences of S phase cells with Wilcoxon. Representative images are from 7 hr. The scale bar represents 20 μm.

(B) Scatterplot of mean intensity of chromatin-bound RPA2 versus γH2AX of single nuclei. Treatments shown for 7 hr for RPE1 TetON E2F6. E2F6 overexpression, Doxy. Black, non-S phase cells (RPA2 < 10 a.u.); orange and red dots, low and high levels of γH2AX, respectively (arbitrary threshold γH2AX = 15 a.u.). p, differences on both axes of S phase cells with Wilcoxon compared to control (−/HU as appropriate). Arrows show change in mean. Representative images are shown. The scale bar represents 20 μm.

(C) Density plot of FACS for RPA2 versus γH2AX intensity; treatments shown are for 7 hr for RPE TetON E2F6 cells. Doxy, 2 μg/ml. Quadrants define RPA2 or γH2AX −/+ cells (−/+ in red and blue, respectively); percentage of cells is shown. Around 10,000 cells were collected per condition. Logarithmic scale identical for all. ^∗∗∗∗p < 0.0001 compared to non-E2F6 control; Student’s t test. Arrows show change of mean.

See also Figures S1 and S2.