RIG-I and dsRNA-induced IFNbeta activation.
Except for viruses that initiate RNA synthesis with a protein primer (e.g., picornaviruses), most RNA viruses initiate RNA synthesis with an NTP, and at least some of their viral (ppp)RNAs remain unblocked during the infection. Consistent with this, most viruses require RIG-I to mount an innate immune response, whereas picornaviruses require mda-5. We have examined a SeV infection whose ability to induce interferon depends on the generation of capped dsRNA (without free 5' tri-phosphate ends), and found that this infection as well requires RIG-I and not mda-5. We also provide evidence that RIG-I interacts with poly-I/C in vivo, and that heteropolymeric dsRNA and poly-I/C interact directly with RIG-I in vitro, but in different ways; i.e., poly-I/C has the unique ability to stimulate the helicase ATPase of RIG-I variants which lack the C-terminal regulatory domain.
Hausmann
Stéphane
S
Department of Microbiology and Molecular Medicine, University of Geneva Medical School, Geneva, Switzerland.
Marq
Jean-Baptiste
JB
Tapparel
Caroline
C
Kolakofsky
Daniel
D
Garcin
Dominique
D
D000818:Animals; D001665:Binding Sites; D002478:Cells, Cultured; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D000072640:Interferon-Induced Helicase, IFIH1; D016899:Interferon-beta / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D011070:Poly I-C / Q000235:genetics; D017434:Protein Structure, Tertiary; D012330:RNA, Double-Stranded / Q000378:metabolism*; D029082:Sendai virus / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
D012330:RNA, Double-Stranded; D014764:Viral Proteins; D049452:Green Fluorescent Proteins; D016899:Interferon-beta; C503356:Ddx58 protein, mouse; C510592:Ifih1 protein, mouse; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases; D000072640:Interferon-Induced Helicase, IFIH1; D011070:Poly I-C