Fig. 4.
CircPTPN11 activates promotes IFN-I via IRF3 to promote the expression of ISGs. RD cells were transfected with either pcDNA3.1-CircPTPN11 or pcDNA3.1 (an empty vector), and then the cells infected with CVB5 (MOI=1) at 24 h post-transfection. Cells and supernatants were harvested at 24 HPI. (A) The secretion of IFN-α2 and IFN-β were determined by ELISA. (B) The expression of vital ISGs and IFN-I mRNA were determined by RT-qPCR. (C) The expression of MDA5, RIG-I, IKKε/p-IKKε, TBK1/p-TBK1 and IRF3/p-IRF3 were determined by Western blotting. (D) The expression of (p-IRF3)2 was determined by Western blotting. (E) The expression of IRF3 and p-IRF3 in nuclear and cytoplasmic fractions were determined by Western blotting. (F) The expression of p-IRF3 in nuclear and cytoplasmic fractions were visualized by Immunofluorescence assay. Data are representative of three independent experiments and are plotted as the mean ± S.D. *P < 0.05, **P < 0.01 and ***P < 0.001 vs. the control group.