Interaction between chicken TRIM25 and MDA5 and their role in mediated antiviral activity against IBDV infection

Abstract

Infectious Bursal Disease Virus (IBDV) is the causative agent of an immunosuppressive disease that affects domestic chickens (Gallus gallus) severely affecting poultry industry worldwide. IBDV infection is characterized by a rapid depletion of the bursal B cell population by apoptosis and the atrophy of this chief lymphoid organ. Previous results from our laboratory have shown that exposure of infected cells to type I IFN leads to an exacerbated apoptosis, indicating an important role of IFN in IBDV pathogenesis. It has been described that recognition of the dsRNA IBDV genome by MDA5, the only known cytoplasmic pattern recognition receptor for viral RNA in chickens, leads to type I IFN production. Here, we confirm that TRIM25, an E3 ubiquitin ligase that leads to RIG-I activation in mammalian cells, significantly contributes to positively regulate MDA5-mediated activation of the IFN-inducing pathway in chicken DF-1 cells. Ectopic expression of chTRIM25 together with chMDA5 or a deletion mutant version exclusively harboring the CARD domains (chMDA5 2CARD) enhances IFN-β and NF-ĸB promoter activation. Using co-immunoprecipitation assays, we show that chMDA5 interacts with chTRIM25 through the CARD domains. Moreover, chTRIM25 co-localizes with both chMDA5 and chMDA5 2CARD, but not with chMDA5 mutant proteins partially or totally lacking these domains. On the other hand, ablation of endogenous chTRIM25 expression reduces chMDA5-induced IFN-β and NF-ĸB promoter activation. Interestingly, ectopic expression of either wild-type chTRIM25, or a mutant version (chTRIM25 C59S/C62S) lacking the E3 ubiquitin ligase activity, restores the co-stimulatory effect of chMDA5 in chTRIM25 knockout cells, suggesting that the E3-ubiquitin ligase activity of chTRIM25 is not required for its downstream IFN-β and NF-ĸB activating function. Also, IBDV-induced expression of IFN-β, Mx and OAS genes was reduced in chTRIM25 knockout as compared to wild-type cells, hence contributing to the enhancement of IBDV replication. Enhanced permissiveness to replication of other viruses, such as avian reovirus, Newcastle disease virus and vesicular stomatitis virus was also observed in chTRIM25 knockout cells. Additionally, chTRIM25 knockout also results in reduced MAVS-induced IFN-β promoter stimulation. Nonetheless, similarly to its mammalian counterpart, chTRIM25 overexpression in wild-type DF-1 cells causes the degradation of ectopically expressed chMAVS.

Pathologic Mechanisms of the Newcastle Disease Virus

“…In addition, RIG-I is also absent in chickens, which is presumably attributable to their higher susceptibility to NDV compared with waterfowls such as ducks and geese [67,68]. Instead of RIG-I, NDV and other RNA viruses are recognized by the other two RLR family members, MDA5 and LGP2, which preserve antiviral competence in chickens [69][70][71][72][73]. The infection of the virulent genotype VIId NDV strain was accompanied by massive MDA5 expression in the oviducts of egg-laying hens and chicken bone-marrow-derived dendritic cells in the early infection stage [74,75].…”

TRIM21 Promotes Rabies Virus Production by Degrading IRF7 through Ubiquitination

“…Ref. [ 44 ] Furthermore, the expression of TRIM25 is upregulated after infection with the infectious bursal disease virus (IBDV), which in turn inhibits the replication of the virus [ 45 , 46 ]. Herein, we found that RABV infection also upregulates the expression of TRIM21, but unlike the mentioned viruses, it promotes the replication of RABV.…”

Exploring TRIM proteins’ role in antiviral defense against influenza A virus and respiratory coronaviruses

“…TRIM25 has been demonstrated to be an RNA-binding protein, which plays a key role in the antiviral interferon response by activating the RIG-I pathway ( Choudhury et al., 2020 ; Xiao et al., 2021 ; Diaz-Beneitez et al., 2022 ). However, new evidence has shown alternative mechanisms for TRIM25 anti-IAV action.…”