Figure 1.

Per2^def mice are radiosensitive with reduced DNA repair capacity

(A) Kaplan-Meier survival of Per2 wild-type (Per2^wt, blue line) or Per2 deficient (Per2^def, red line) C57BL/6 mice following whole body exposure to different radiation doses. WBR:7-12 Gy; Data are represented as mean ± SEM, n = 12-20/group, Kaplan-Meier survival analysis Log rank test.

(B) DNA repair capacity showing representative images of alkaline comet assay of Per2^wt and Per2^def BMMNCs at indicated times (30 min or 1 h) after 1 Gy radiation; Scale bar, 50 μm.

(C) Quantitation of DNA repair capacity by tailed DNA (%) and tail moment (%). Data are represented as mean ± SEM, n = 50, ∗∗p < 0.01, ∗∗∗p < 0.001, Student’s t test.

(D) Representative images of NHEJ DNA repair capacity by 53BP1 foci analysis in Per2^wt and Per2^def BMMNCs 2 h after 2 Gy radiation; Scale bar, 2 μm.

(E) Quantitation of NHEJ DNA repair capacity by counting 53BP1 foci (left) and γH2AX foci (right) per nucleus. Data are represented as mean ± SEM, n = 40, ∗p < 0.05, ∗∗p < 0.01, ns p > 0.05, Student’s t test.

(F) Representative images of HR DNA repair capacity by Rad51 foci analysis in Per2^wt and Per2^def BMMNCs 2 h after 2 Gy radiation; Scale bar, 2 μm.

(G) Quantitation of HR DNA repair capacity by counting Rad51 foci (left) and γH2AX foci (right) per nucleus. Data are represented as mean ± SEM, n = 40, ∗p < 0.05, ∗∗p < 0.01, ns p > 0.05, Student’s t test.