Measles virus takes a two-pronged attack on PP1.

During viral infection, RIG-I-like receptors (RLRs) are activated upon dephosphorylation by the phosphatase PP1, resulting in type I interferon production. In this issue, Davis et al. (2014) and Mesman et al. (2014) show that measles virus inhibits this antiviral response by targeting PP1 and thus preventing RLR dephosphorylation and activation.