Viral Defense: It Takes Two MAVS to Tango

To defend cells against viruses, the MAVS (mitochondrial antiviral signaling) adaptor protein initiates an antiviral signaling cascade from mitochondrial membranes. In this issue, show that MAVS also localizes to the membranes of peroxisomes, where it rapidly induces expression of a subset of antiviral genes that curb viral replication until mitochondrial MAVS can induce a sustained antiviral response.