Activation of FOXO3A is accelerated in DNA repair deficientErcc1-/Δmice. Immunoblot detection of FOXO3A in nuclear (top) and cytosolic (bottom) extracts from liver lysates isolated from 8 (A) and (B) 16-week-old mice WT or ERCC1-deficient mice. (C-D) Expression of FOXO3A-regulated genes measured by qRT-PCR in livers of WT and Ercc1-/Δ mice at 8 weeks (middle-age) and 16 weeks of age (old). WT at the same age is set as 1; red dashed line. n = 6–8 per age; Student's one-tailed t-test, *p < 0.05. (E-F) Expression of FOXO3A-regulated genes measured by qRT-PCR in liver of WT mice at 50 weeks (middle-age, E) and 110–120 weeks of age (old, F). WT at 16 weeks of age is set at 1; black dashed line. n = 4–6 per age; Student's one-tailed t-test, *p < 0.05, * *p < 0.01, * **p < 0.001.