M1 and M2: the evolutionarily conserved dsRNA-binding motifs (dsRBMs) present in PKR, PACT, and TRBP also mediate protein-protein interactions. PBM: PACT Binding Motif present in PKR. M3 domain of PACT is essential for PKR activation. M3 (aka medipal domain) of TRBP mediates TRBP’s interactions with Merlin, Dicer, and PACT. Blue Arrows indicate known sites of phosphorylation on each protein. CARD: Caspase activation and recruitment domain, site of oligomerization with CARD domains in other proteins. DExD/H Helicase: helicase domain in RIG-I with inherent ATPase activity. CTD/RD: C-terminal domain and regulatory domain of RIG-I that also is an interaction site of PACT. I-VI: conserved helicase motifs in RIG-I.