Figure 3.

Although p16 overexpression, like persistent DNA damage, can induce cellular senescence, it does not alter NMD activity. a, left panel, representative SA β-gal staining images of RPE1 reporter cells after 24-h treatment with either H₂O or bleomycin (Bleo), followed by 96-h recovery. Right panel, percentage of SA β-gal–positive RPE1 cells after 24-h treatment with either H₂O or bleomycin, followed by 96-h recovery. Data represent the mean ± S.D. of three independent experiments. *, p ≤ 0.05 (paired t test). b, left panel, representative images of RPE1 reporter cells expressing either empty vector or p16 after SA β-gal staining. Right panel, percentage of SA β-gal–positive RPE1 cells expressing either empty vector or p16. Data represent the mean ± S.D. of three independent experiments. *, p ≤ 0.05 (paired t test). c, top panel, ratios of CBR:CBG bioluminescence signals in RPE1 reporter cells expressing either empty vector or p16. Data represent the mean ± S.D. of three independent experiments. NS, p > 0.05 (paired t test). Bottom panel, Western blot showing γH2AX levels in cells overexpressing either empty vector or p16.