DDX58, also named RIG-1, is a member of the DExD/H-box-containing RNA helicase family. DDX58 was first reported as a retinoic acid-inducible gene and subsequently characterized as a pattern recognition receptor (PRR). DDX58 is responsible for sensing cytosolic viral RNA and has been shown to initiate innate antiviral immune responses. DDX58 is composed of two caspase recruitment domains (CARDs), a helicase domain, and a C-terminal regulatory domain (CTD). In response to virus infections, the DDX58 CTD domain binds 5'-triphosphorylated dsRNA, which induces multimerization of DDX58 with the adaptor molecule MAVS on the mitochondria through the CARD domains. MAVS transduces the signal to activate downstream transcription factors, such as IRF-3, IRF-7, and NF-κB, leading to production of proinflammatory cytokines and type I interferons.