NFIB and infection: Figure 1C shows that the infection of PRRSV could inhibit the miRNA-induced silencing of luciferase. To confirm the above results, the endogenous gene NFIB was selected to perform a similar experiment, and the results in Figure 1D and E show that PRRSV also inhibited the si-NFIB- and miR-373-induced silencing of NFIB.