Convergence of the NF-κB and IRF pathways in the regulation of the innate antiviral response

The type I interferon (IFN) α and β promoters have been a leading paradigm of virus-activated transcriptional regulation for more than two decades, and have contributed substantially to our understanding of virus-inducible gene regulation, the coordinated activities of NF-κB and IRF transcription factors, the temporal and spatial recruitment of co-activators to the enhanceosome, and signaling pathways that trigger the innate antiviral response. In 2003, the ISICR Milstein Award was presented to John Hiscott of McGill University and Tom Maniatis of Harvard University for their ongoing research describing the mechanisms of regulation of type 1 interferon genes and specifically for the identification of key signaling kinases involved in phosphorylation of the transcription factors IRF-3 and IRF-7. The specific roles played by IRFs and the IKK-related kinases TBK1 and IKKɛ are now recognized within the broader framework of TLR and RIG-I signaling pathways. This review summarizes the unique features of the IKK-related kinases and offers a summary of recent advances in the regulation of the early host response to virus infection.