Singapore Grouper Iridovirus VP131 Drives Degradation of STING-TBK1 Pathway Proteins and Negatively Regulates Antiviral Innate Immunity
Ya Zhang, Xiaolin Gao, Xinmei Yang, Yu Wang, Wenji Wang, Xiaohong Huang, Qiwei Qin, Youhua Huang
Abstract
STING has been identified as a critical factor participating in the innate immune response which recruits and phosphorylates TBK1 and IFN regulatory factor 3 (IRF3) to induce IFN production and defend against viral infection. However, viruses also distort the STING-TBK1 pathway to negatively regulate the IFN response and facilitate viral replication. Here, we reported that SGIV VP131 interacted with EcSTING within the ER and degraded EcSTING, leading to the suppression of IFN production and the promotion of SGIV infection. These results for the first time demonstrated that fish iridovirus evaded the host antiviral response via abrogating the STING-TBK1 signaling pathway.