Fig. 3.

PDCoV infection prevents the production of IFN-λ1 by blocking activation of NF-κB and IRF. LLC-PK1 cells were transfected with the luciferase reporter plasmids p-55λ1mut.IRF-Luc (A), p-55λ1mut.NF-κB-Luc (B) or p-55λ1mut.IRF/mut.NF-κB-Luc (C) together with pRL-TK, and then mock-infected or infected with PDCoV at a MOI of 0.05. At 12 hpi, the cells were mock-infected or infected with SeV for 12 h. Cell lysates were prepared for dual-luciferase reporter assays. All data are presented as the means ± SD of three independent experiments (**p < 0.01). Western blot analysis with anti-PDCoV N protein antibody showed that PDCoV can normally infect cells, and β-actin was used as a control for sample loading.