Fig. 2.

FAN1-deficient DT40 cells are hypersensitive to DNA cross-linking agents. DT40 cells of the indicated genotypes were exposed to γ-rays, UV, MMS (Fig. S2 F–H), and camptothecin (A), cisplatin (B), and mitomycin C (C). The doses of the agents are shown on the x axes on a linear scale, whereas the fractions of surviving colonies are displayed on the y axis on a logarithmic scale. Each data point represents an average of at least three independent experiments ±SD. #1 and #2, two independent FAN1 knockout clones. FAN1^−/−/GdFAN1 denotes a FAN1 knockout clone stably transfected with an expression vector encoding a FAN1 ORF. As shown, expression of this protein rescued the hypersensitive phenotype of the FAN1 knockout cells.