NSD3 keeps IRF3 active

In this issue of JEM, Wang et al. (https://doi.org/10.1084/jem.20170856) show a novel antiviral innate mechanism by which methyltransferase NSD3 directly monomethylates a transcription factor IRF3 and maintains IRF3 phosphorylation to enhance its transcriptional activity, consequently promoting antiviral innate immune responses.