Antagonizing Interferon-Mediated Immune Response by Porcine Reproductive and Respiratory Syndrome Virus

Figure 1

Interference of type I IFN production by PRRSV proteins. Activation of RLR pathway and signaling by viral dsRNA is shown. Viral dsRNA is generated during PRRSV replication. “P” besides IRF3 and IRF7 indicates phosphorylation. Red-colored blocks indicate PRRSV proteins known to inhibit the signaling molecules indicated. PRRSV nsp1α inhibits IRF3 association with CBP, enhances CBP degradation, and interferes with IκB degradation. And nsp1β inhibits IRF3 phosphorylation and nuclear translocation. Also nsp2 inhibits IRF3 phosphorylation and nuclear translocation, interferes with IκB polyubiquitination, and prevents its degradation. And nsp11 inhibits IRF3 phosphorylation and nuclear translocation via degrading IPS-1 mRNA.