Article

SUMOylation of RIG-I positively regulates the type I interferon signaling

Center for Molecular Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
Protein & Cell (Impact Factor: 3.22). 03/2010; 1(3):275-83. DOI: 10.1007/s13238-010-0030-1
Source: PubMed

ABSTRACT Retinoic acid-inducible gene-I (RIG-I) functions as an intracellular pattern recognition receptor (PRR) that recognizes the 5'-triphosphate moiety of single-stranded RNA viruses to initiate the innate immune response. Previous studies have shown that Lys63-linked ubiquitylation is required for RIG-I activation and the downstream anti-viral type I interferon (IFN-I) induction. Herein we reported that, RIG-I was also modified by small ubiquitin-like modifier-1 (SUMO-1). Functional analysis showed that RIG-I SUMOylation enhanced IFN-I production through increased ubiquitylation and the interaction with its downstream adaptor molecule Cardif. Our results therefore suggested that SUMOylation might serve as an additional regulatory tier for RIG-I activation and IFN-I signaling.

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