Figure 3

PKR inhibited NDV replication in HeLa cells. A. HeLa cells were transfected with the siRNA specific for PKR (100 pmol/mL) or control siRNA for 48 h and then infected with NDV strain Herts/33 or mock infected. The cells were harvested at 12 hpi and then collected for western blot analysis. The protein levels were determined with anti-PKR, anti-p-eIF2α, and anti-NP antibodies. β-actin was used as a protein loading control. B. The intensity band ratio of PKR to β-actin. Representative results are shown with graphs representing the ratio of PKR to β-actin normalized to the control condition. Data are presented as means from three independent experiments. Significance was analyzed using two-tailed Student’sttest. ***, P ≤ 0.001. C. Determination of the NDV replication in PKR knockdown HeLa cells. The extracellular virus yields were determined at 12 hpi and expressed as TCID₅₀/mL. Data are presented as means from three independent experiments. Significance was analyzed using two-tailed Student’s t-test. **, p ≤ 0.01. D. HeLa cells were transfected with pcDNA3.1 or pcDNA-PKR. At 24 hpi, the cells were infected with NDV strain Herts/33 at an MOI of 1 or mock infected and harvested at 12 hpi. The protein levels were determined with anti-PKR or anti-NP antibodies. β-actin was used as a protein loading control. E. The intensity band ratio of PKR to β-actin. Representative results are shown with graphs representing the ratio of PKR to β-actin normalized to the control condition. Data are presented as means from three independent experiments. Significance was analyzed using two-tailed. Student’sttest. ***, P ≤ 0.001. F. Determination of the NDV replication on PKR overexpression in HeLa cells. The extracellular virus yields were determined at 12 hpi and expressed as TCID₅₀/mL. Data are presented as means from three independent experiments. Significance was analyzed using two-tailed Student’s t-test. ***, p ≤ 0.001.