FIG 3.

PKR is not blocked by DENV4 or ZIKV but shows delayed activation. (A) Cells were infected with DENV4 (MOI 2) and ZIKV (MOI 3) and incubated for 1 hour 30 minutes before the virus inoculum was removed. Then, cells were stimulated with poly(I:C) at 3 h.p.i. with 10 µg/mL for 6 hours. Analysis for quantification of the cell population expressing p-eIF2α after stimulation with poly(I:C) was performed by flow cytometry. Data from three independent experiments. (B) Immunofluorescence of A549 WT cells infected with DENV4 for 48 h.p.i. in semi-solid medium. Cells fixed, permeabilized, and co-stained with 4′,6-diamidino-2-phenylindole (DAPI), anti-dsRNA and anti-p-eIF2α. Representative image of three independent experiments. In the column chart, bars represent the means ± standard error of the mean. Statistical analysis was performed by one-way analysis of variance, followed by Tukey’s test for multiple comparisons. **P ≤ 0.01. ns, no statistical difference.