FIG. 4.

Effects of polyIC and 3p-EGFP-mRNA on PKR activation and cell proliferation. D3 cells were transfected with 300 ng/mL 3p-EGFP-mRNA (EGFP mRNA, coding sequence) or polyIC. (A) The activation of PRK was indicated by the increase of phosphorylated eIF2α (indicated by fluoresce intensity) with flow cytometry after immunostaining of the cells with antibodies against phosphorylated eIF2α. (B) Cell proliferation was determined by TB staining. The values are means±SD of a representative experiment performed in triplicate. (C) Cell cycle progression was analyzed by flow cytometry. Reduction of G2/M phase cells was indicated by arrows. All experiments were repeated at least twice with similar results.