Additional file 3 of Foot-and-mouth disease virus VP4 interferes with host interferon response by targeting the nuclear translocation of interferon regulatory factor 3 (IRF3)

Additional file 3. VP4 inhibits type I IFN signaling and antiviral gene transcription. A HEK293T cells transiently transfected with Flag-VP4 or control was infected with PR8-GFP while B Flag-VP4 or control vector stably expressing 3D4/21 cells were stimulated with poly I:C and samples were collected at designated time points. Intact and phosphorylated states of IRF3, TBK1, STAT1, IҡBα, and p65 were assessed by immunoblotting. β-actin served as an internal reference to ensure equal protein loading. C Flag-VP4 and the control plasmid, transiently transfected HEK293T cells, were inoculated with PR8-GFP. Cells were sampled at specified time points. Subsequently, cellular RNA was isolated. The transcription levels of antiviral genes were subsequently quantified by qRT-PCR. All qRT-PCR data represent at least two independent experiments, each with similar results, and the values are expressed as the mean ± SD of three biological replicates. All the immunoblot data represent at least two independent experiments, each with similar results. Student’s t-test; *p < 0.05; **p < 0.01; ***p < 0.001.