Incoming RNA virus nucleocapsids containing a 5'-triphosphorylated genome activate RIG-I and antiviral signaling

13.03.2013

Weber M, Gawanbacht A, Habjan M, Rang A, Borner C, Schmidt AM, Veitinger S, Jacob R, Devignot S, Kochs G, García-Sastre A, Weber F.

Cell Host Microbe. 2013;13(3):336-46

Cell Host Microbe.         online article

Here we show that incoming viral nucleocapsids containing dsRNA with a triphosphorylated 5’ppp terminus trigger an antiviral type I interferon response via RIG-I helicase, the MAVS adaptor protein and the transcription factor IRF-3. RIG-I interacts with the 5’ppp terminus of dsRNA independent of mammalian cofactors or viral polymerase. As a result RIG-I undergoes a conformational change leading to its homo-oligomerization. Our results define cytoplasmic viral nucleocapsids with 5’ppp dsRNA as RIG-I activators and the most proximal RIG-I-sensitive step during infection.