FIGURE 3.

5′-Phosphate contributes to IFN-β induction and apoptosis caused by PRNAs. Cells were transfected with 50-nt PLUC50S, AS, or 50-bp PsiLUC50 PRNAs or CsiLUC20. A, effect of CIP phosphatase treatment compared with buffer alone on IFN-β induction at 5 h as measured by real time PCR. The mean and standard deviations from three independent experiments are shown. ^*, p < 0.05. B, Western blot analysis showing PARP cleavage at 24 h and phosphorylation of PKR and eIF-2α at 8 h following transfection of CIP-treated or untreated RNAs.