Fig. S6.

Sensitivity of polymerase-deficient cells to agents that damage DNA. (A) Resistance to ionizing radiation as in Fig. 6, except using a panel of MEFs generated independently, derived from mice from a different litter. (B) Cellular resistance to methyl methanesulfonate (MMS) was determined after a 4-h exposure and (C) resistance to paraquat after exposure for 18 h. Error bars represent the SD from the mean survival at each dose. (D and E) Western blot analysis of Polm^−/−Poll^−/− subclones used in Fig. 6B that were engineered to express WT or catalytically inactive Pol μ (D) or Pol λ (E) proteins.