FIG 8 .

PKR is required for HCV-mediated inhibition of p53. (A) Levels of phosphorylated eIF2α (pS51) (left) and global protein synthesis (right) in HCV core (-) and HCV core (+) populations of control versus PKR^KO cells. (B) MFI values for global protein synthesis from the indicated populations of control and PKR^KO cell lines are expressed as the percentages of protein synthesis relative to JFH1/GND-electroporated controls. (C) Control cells were labeled in the presence or absence of the translational inhibitor cycloheximide (CHX) (50 μg/ml) to confirm specificity for newly synthesized proteins. Values in panels B and C represent the means ± SEM from three independent experiments. ***, P < 0.0001 by two-way ANOVA with Bonferroni’s correction for multiple comparisons. (D) p53 accumulation in HCV core (-) and HCV core (+) populations of control versus PKR^KO cells electroporated with the indicated HCV RNA and treated 72 h later with 100 μM etoposide (ETOP) or DMSO for 2 h. Numbers indicate the percentages of p53-positive cells following etoposide treatment. (E) Immunofluorescence confocal microscopy for p53 and HCV core protein in JFH1-QL RNA-electroporated PKR^KO cells treated as described for panel D. Nuclei were labeled with DAPI. Bar, 50 μm.