RIGorous detection: exposing virus through RNA sensing.

Virus infection in mammals elicits a variety of defense responses that are initiated by signals from virus-sensing receptors expressed by the host. These receptors include the ubiquitously expressed RIG-I-like receptor (RLR) family of RNA helicases. RLRs are cytoplasmic proteins that act in cell-intrinsic antiviral defense by recognizing RNAs indicative of virus presence. Here, we highlight recent progress in understanding how RLRs discriminate between the RNA content of healthy versus virus-infected cells, functioning as accurate sensors of virus invasion.