5-FU Treatment Induces a TDG-Dependent S-Phase Delay

The histograms show the effect of the 5-FU treatment on the relative cell-cycle distribution (% cells) of TDG-proficient and -deficient MEFs (A), and of TDG knockout cell lines stably transfected with a plasmid expressing Tdg from its authentic promoter (B). 5-FU treatment of TDG-proficient cells results in a significant accumulation cells in S-phase at the expense of G1 cells, whereas TDG-deficient cells show only insignificant changes in cell-cycle distribution. Expression of wild-type Tdg in knockout MEFs partially restored the 5-FU–dependent S-phase delay. The data shown represent averages of three independent experiments with fold changes upon 5-FU treatment.

pC, empty vector; pTdg, vector expressing TDG.