Viral Infection: An Evolving Insight into the Signal Transduction Pathways Responsible for the Innate Immune Response

Figure 1

Signaling by the innate immune system that is inhibited by several viral proteins. This model depicts the salient features of TLR-induced NF-κB and IRF3 induction. Several poxviral proteins N1, C6, A14 A46, and A52 inhibit the activation of NF-κB and/or IRF3 signaling pathways, by interacting with and inhibiting the activity of the classical IKK complex (IKKα/β/γ) as well as the nonclassical IKKε/TBK1 complex. HCV protein NS5A inhibits TIR signaling by MyD88, its NS3/4A digests MAVS to inhibit RLR signaling, and its core protein inhibits Jak/Stat signaling. Finally, HIV Vif and Vpr degrade IRF3.