Figure 3.
CtipS326A/− ES cells are resistant to MMC-induced genotoxic stress. Isogenic Ctip+/− and CtipS326A/− ES cells were examined for mitomycin C (MMC) sensitivity in clonogenic survival assays, together with ES cells homozygous for the hypomorphic Brca1Δ223–763 mutation (Brca1Δ223–763/Δ223–763) and control ES cells (Brca1+/−). Cells were treated with various concentrations of MMC for 4 h, allowed to recover for 7–9 d, and surviving colonies were stained with Crystal violet. Survival is calculated as a percentage of colonies in the mock-treated plates. Each subclone was tested in triplicate, and the error bars represent the SEM of survival for each subclone.
