Caspase-12 controls West Nile virus infection via the viral RNA receptor RIG-I

Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA.
Nature Immunology (Impact Factor: 24.97). 10/2010; 11(10):912-9. DOI: 10.1038/ni.1933
Source: PubMed

ABSTRACT Caspase-12 has been shown to negatively modulate inflammasome signaling during bacterial infection. Its function in viral immunity, however, has not been characterized. We now report an important role for caspase-12 in controlling viral infection via the pattern-recognition receptor RIG-I. After challenge with West Nile virus (WNV), caspase-12-deficient mice had greater mortality, higher viral burden and defective type I interferon response compared with those of challenged wild-type mice. In vitro studies of primary neurons and mouse embryonic fibroblasts showed that caspase-12 positively modulated the production of type I interferon by regulating E3 ubiquitin ligase TRIM25-mediated ubiquitination of RIG-I, a critical signaling event for the type I interferon response to WNV and other important viral pathogens.

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Penghua Wang