Interferons (IFNs) are involved in a multitude of immune interactions during viral infections and play a major role in both the induction and regulation of innate and adaptive antiviral mechanisms.  During infection, host-virus interactions signal downstream molecules such as transcription factors such as IFN regulatory factor-3 (IRF3) which can act to stimulate transcription of IFN-a/b genes.  IRF7 has been shown to play a role in the transcriptional activation of virus-inducible cellular genes, including interferon beta chain genes.  IRF7 play a major role in the innate immune pathway, interacting with the Toll-like receptor (TLR) adaptor proteins MyD88 and Tirp/TRAM and functioning as an intermediate TLR4 and TLR9 signaling.  There are at least four differentially spliced isoforms of IRF7, although their function has not been clearly established.