IFNB1 and infection: Due to proteolytic inactivation of RIG-I after the infection (see below), MDA5 activates the RIG-I-like receptor (RLR) signaling cascade, inducing the activation of two central transcription factors, interferon (IFN) regulatory factor 3 (IRF3) and NF-κB, leading to the transcriptional induction of IFN-β [7].