To further understand the role of AGO2 in RNA virus-induced antiviral signaling, the phosphorylation status of IRF3 (p-IRF3) and STAT1 (p-STAT1) was estimated in AGO2 knockout (AGO2−/−) 293 and A549 cells and in control (AGO2WT) cells following infection with different RNA viruses, including WSN, DelNS1 WSN and SeV (Figure 1B; Figures S1C and S1D). Here, IRF3 is linked to infection.