scholarly journals Dependence of RIG-I Nucleic Acid-Binding and ATP Hydrolysis on Activation of Type I Interferon Response

2016 ◽  
Vol 16 (4) ◽  
pp. 249 ◽  
Author(s):  
Yu Mi Baek ◽  
Soojin Yoon ◽  
Yeo Eun Hwang ◽  
Dong-Eun Kim
2020 ◽  
Author(s):  
Ole Kristian Greiner-Tollersrud ◽  
Vincent Boehler ◽  
Eva Bartok ◽  
Máté Krausz ◽  
Aikaterini Polyzou ◽  
...  

AbstractDeficiency of adenosine deaminase 2 (DADA2) is a severe, congenital syndrome, which manifests with hematologic, immunologic and inflammatory pathologies. DADA2 is caused by biallelic mutations in ADA2, but the function of ADA2, and the mechanistic link between ADA2 deficiency and the severe inflammatory phenotype remains unclear. Here, we show that monocyte-derived proteomes from DADA2 patients are highly enriched in interferon response proteins. Using immunohistochemistry and detailed glycan analysis we demonstrate that ADA2 is post-translationally modified for sorting to the lysosomes. At acidic, lysosomal pH, ADA2 acts as a novel DNase that degrades cGAS/Sting-activating ligands. Furthermore, we define a clear structure-function relationship for this acidic DNase activity. Deletion of ADA2 increased the production of cGAMP and type I interferons upon exposure to dsDNA, which was reverted by ADA2 overexpression or deletion of STING. Our results identify a new level of control in the nucleic acid sensing machinery and provide a mechanistic explanation for the pathophysiology of autoinflammation in DADA2.One Sentence SummaryADA2 is a lysosomal nuclease controlling nucleic acid sensing and type I interferon production.


2019 ◽  
Author(s):  
Caitlyn T. Hoffpauir ◽  
Samantha L. Bell ◽  
Kelsi O. West ◽  
Tao Jing ◽  
Sylvia Torres-Odio ◽  
...  

ABSTRACTTripartite motif-containing proteins (TRIMs) play a variety of recently described roles in innate immunity. While many TRIMs regulate type I interferon (IFN) expression following cytosolic nucleic acid sensing of viruses, their contribution to innate immune signaling and gene expression during bacterial infection remains largely unknown. Because Mycobacterium tuberculosis is a potent activator of cGAS-dependent cytosolic DNA sensing, we set out to investigate a role for TRIM proteins in regulating macrophage responses to M. tuberculosis. Here we demonstrate that TRIM14, a non-canonical TRIM that lacks an E3 ligase RING domain, is a critical negative regulator of the type I IFN response in macrophages. We show that TRIM14 physically interacts with both cGAS and TBK1 and that macrophages lacking TRIM14 dramatically hyperinduce interferon stimulated gene (ISG) expression following cytosolic nucleic acid transfection, IFN-β treatment, and M. tuberculosis infection. Consistent with a defect in resolution of the type I IFN response, Trim14 knockout (KO) macrophages have more phospho-Ser754 STAT3 relative to phospho-727 and fail to upregulate the STAT3 target Socs3 (Suppressor of Cytokine Signaling 3), which is required to turn off IFNAR signaling. These data support a model whereby TRIM14 acts as a scaffold between TBK1 and STAT3 to promote phosphorylation of STAT3 at Ser727 and enhance negative regulation of ISG expression. Remarkably, Trim14 KO macrophages hyperinduce antimicrobials like Inos2 and are significantly better than control cells at limiting M. tuberculosis replication. Collectively, these data reveal a previously unappreciated role for TRIM14 in resolving type I IFN responses and controlling M. tuberculosis infection.


Author(s):  
Lai Wei ◽  
Siqi Ming ◽  
Bin Zou ◽  
Yongjian Wu ◽  
Zhongsi Hong ◽  
...  

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Elena N. Judd ◽  
Alison R. Gilchrist ◽  
Nicholas R. Meyerson ◽  
Sara L. Sawyer

Abstract Background The Type I interferon response is an important first-line defense against viruses. In turn, viruses antagonize (i.e., degrade, mis-localize, etc.) many proteins in interferon pathways. Thus, hosts and viruses are locked in an evolutionary arms race for dominance of the Type I interferon pathway. As a result, many genes in interferon pathways have experienced positive natural selection in favor of new allelic forms that can better recognize viruses or escape viral antagonists. Here, we performed a holistic analysis of selective pressures acting on genes in the Type I interferon family. We initially hypothesized that the genes responsible for inducing the production of interferon would be antagonized more heavily by viruses than genes that are turned on as a result of interferon. Our logic was that viruses would have greater effect if they worked upstream of the production of interferon molecules because, once interferon is produced, hundreds of interferon-stimulated proteins would activate and the virus would need to counteract them one-by-one. Results We curated multiple sequence alignments of primate orthologs for 131 genes active in interferon production and signaling (herein, “induction” genes), 100 interferon-stimulated genes, and 100 randomly chosen genes. We analyzed each multiple sequence alignment for the signatures of recurrent positive selection. Counter to our hypothesis, we found the interferon-stimulated genes, and not interferon induction genes, are evolving significantly more rapidly than a random set of genes. Interferon induction genes evolve in a way that is indistinguishable from a matched set of random genes (22% and 18% of genes bear signatures of positive selection, respectively). In contrast, interferon-stimulated genes evolve differently, with 33% of genes evolving under positive selection and containing a significantly higher fraction of codons that have experienced selection for recurrent replacement of the encoded amino acid. Conclusion Viruses may antagonize individual products of the interferon response more often than trying to neutralize the system altogether.


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