Skip to main content
Figure 4 | BMC Developmental Biology

Figure 4

From: G1 checkpoint establishment in vivo during embryonic liver development

Figure 4

High DNA damage repair capacity and low apoptosis in E15.5 compared to in E11.5 embryonic liver cells. (A) In vitro NHEJ (non-homologous end-joining) activity was assayed and quantified by plasmid-based quantitative PCR (see Methods). Related NHEJ activity was analyzed by paired Student t test. IR-induced NHEJ activity was significantly higher at E15.5 than at E11.5. (B) Levels of related DNA repair proteins RAD51 and Ligase IV by WB. (C) Left panel: Pregnant mice were exposed to 6 Gy IR. At the indicated time points, E11.5 and E15.5 liver tissue was fixed for γH2AX foci (DSB foci) staining. Nuclear γH2AX foci-positive cells were enumerated. The mean ± SD was from 2 independent experiments. IR induced γH2AX foci-positive cells at different time points were statistically compared to controls, respectively. P value ≤0.05 and ≤ 0.01 was denoted as * and **, respectively. Right panel: Representative γH2AX staining showed that IR-induced DSB foci-positive cells were more dramatically reduced 24 hours after IR in E15.5 than in E11.5 liver cells. (D) Pregnant mice were exposed to 6 Gy IR. At 24 hours after IR, E11.5 and E15.5 liver tissue was fixed for TUNEL staining. Percentages of early apoptotic cells with nuclear FITC labeled nicked DNA vs. DAPI stained liver cells were calculated based on two sections in each case.

Back to article page