FIG. 3.

E1b55K C-terminal mutant proteins with defects in the degradation of the MRN complex. U2OS cells were infected (MOI of 50) with WT Ad5, the ΔE1b55K mutant dl110, or the R443 (A) or Y444A (B) mutant virus, and cells were harvested at the times postinfection indicated above the gels. Lysates were analyzed by immunoblotting with the indicated antibodies, and the results were compared to those from mock-infected cells. GAPDH served as a loading control. Nbs1-P-S343, Nbs1 phosphorylated at S343.