First Author | Chen W | Year | 2013 |
Journal | Cell | Volume | 152 |
Issue | 3 | Pages | 467-78 |
PubMed ID | 23374343 | Mgi Jnum | J:193456 |
Mgi Id | MGI:5468580 | Doi | 10.1016/j.cell.2013.01.011 |
Citation | Chen W, et al. (2013) Induction of Siglec-G by RNA Viruses Inhibits the Innate Immune Response by Promoting RIG-I Degradation. Cell 152(3):467-78 |
abstractText | RIG-I is a critical RNA virus sensor that serves to initiate antiviral innate immunity. However, posttranslational regulation of RIG-I signaling remains to be fully understood. We report here that RNA viruses, but not DNA viruses or bacteria, specifically upregulate lectin family member Siglecg expression in macrophages by RIG-I- or NF-kappaB-dependent mechanisms. Siglec-G-induced recruitment of SHP2 and the E3 ubiquitin ligase c-Cbl to RIG-I leads to RIG-I degradation via K48-linked ubiquitination at Lys813 by c-Cbl. By increasing type I interferon production, targeted inactivation of Siglecg protects mice against lethal RNA virus infection. Taken together, our data reveal a negative feedback loop of RIG-I signaling and identify a Siglec-G-mediated immune evasion pathway exploited by RNA viruses with implication in antiviral applications. These findings also provide insights into the functions and crosstalk of Siglec-G, a known adaptive response regulator, in innate immunity. |