The viral RNA recognition sensor RIG-I is degraded during encephalomyocarditis virus (EMCV) infection.
RNA helicase-like receptors MDA-5 but not RIG-I has been shown to be essential for triggering innate immune responses against picornaviruses. However, virus-host co-evolution has selected for viruses capable of replicating despite host cells antiviral defences. In this report, we demonstrate that RIG-I is degraded during encephalomyocarditis virus (EMCV) infection. This effect is mediated by both the viral-encoded 3C protease and caspase proteinase. In addition, we show that RIG-I overexpression confers IFN-beta promoter activation during EMCV infection, in MDA-5 knockout (MDA-5(-/-)) mouse embryo fibroblasts. This induction is followed by a strong inhibition reflecting the ability of EMCV to disrupt RIG-I signalling. Taken together, our data strongly suggest that during evolution RIG-I has been involved for triggering innate immune response to picornavirus infections.
Papon
Laura
L
Université Montpellier 1, Centre d'études d'agents Pathogènes et Biotechnologies pour la Santé (CPBS), F-34095 Montpellier, France.
Oteiza
Alexandra
A
Imaizumi
Tadaatsu
T
Kato
Hiroki
H
Brocchi
Emiliana
E
Lawson
T Glen
TG
Akira
Shizuo
S
Mechti
Nadir
N
D000086042:3C Viral Proteases; D000818:Animals; D018188:Cardiovirus Infections / Q000276:immunology* / Q000821:virology; D020169:Caspases / Q000276:immunology / Q000378:metabolism; D003546:Cysteine Endopeptidases / Q000276:immunology / Q000378:metabolism; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases / Q000276:immunology / Q000378:metabolism*; D004686:Encephalomyocarditis virus / Q000276:immunology* / Q000378:metabolism; D005786:Gene Expression Regulation; D006367:HeLa Cells; D006801:Humans; D007113:Immunity, Innate; D000072640:Interferon-Induced Helicase, IFIH1; D016899:Interferon-beta / Q000276:immunology*; D051379:Mice; D011401:Promoter Regions, Genetic; D014764:Viral Proteins / Q000276:immunology / Q000378:metabolism
D014764:Viral Proteins; D016899:Interferon-beta; D020169:Caspases; D003546:Cysteine Endopeptidases; D000086042:3C Viral Proteases; C503356:Ddx58 protein, mouse; C510592:Ifih1 protein, mouse; D000071457:DEAD Box Protein 58; D053487:DEAD-box RNA Helicases; D000072640:Interferon-Induced Helicase, IFIH1