Overexpression of PCNA Attenuates Oxidative Stress-Caused Delay of Gap-Filling during Repair of UV-Induced DNA Damage

Figure 6

The effect of PCNA knockdown on the repair of oxidative DNA damage. (a) Comet assay. AGS cells transfected with pLKO-1 shPCNA to knock down PCNA or control vector were treated with 20 μM H₂O₂ for indicated periods of time before being harvested for comet-Fpg/Endo III assay to monitor the levels of H₂O₂-induced DNA lesions in cells. Bottom panel: western analysis of PCNA protein with levels of β-actin protein as a loading control. (b) Immunostaining analysis and (c) ELISA. Cells transfected with pLKO-1 shPCNA or control vector were treated with 1 mM H₂O₂ for 1 and 4 h before being harvested for immunofluorescence and ELISA assays of 8-oxo-dG. Typical images were shown. for control, that is, cells without treatment. for .

(a)

(b)

(c)