12
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Innate immune evasion strategies of DNA and RNA viruses

      review-article
      1 , 1 , 2
      Current Opinion in Microbiology
      Elsevier Ltd.

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Highlights

          • Viruses are sensed by host pattern recognition receptors during infection.

          • Viruses must inhibit the innate antiviral immune response for full replication.

          • Viruses can sequester innate immune proteins or target them for degradation.

          • RNA viruses encode proteases that cleave host innate immune proteins.

          Abstract

          Upon infection, both DNA and RNA viruses can be sensed by pattern recognition receptors (PRRs) in the cytoplasm or the nucleus to activate antiviral innate immunity. Sensing of viral products leads to the activation of a signaling cascade that ultimately results in transcriptional activation of type I and III interferons, as well as other antiviral genes that together mediate viral clearance and inhibit viral spread. Therefore, in order for viruses to replicate and spread efficiently, they must inhibit the host signaling pathways that induce the innate antiviral immune response. In this review, we will highlight recent advances in the understanding of the mechanisms by which viruses evade PRR detection, intermediate signaling molecule activation, transcription factor activation, and the actions of antiviral proteins.

          Related collections

          Most cited references36

          • Record: found
          • Abstract: found
          • Article: not found

          Influenza A virus NS1 targets the ubiquitin ligase TRIM25 to evade recognition by the host viral RNA sensor RIG-I.

          The ubiquitin ligase TRIM25 mediates Lysine 63-linked ubiquitination of the N-terminal CARD domains of the viral RNA sensor RIG-I to facilitate type I interferon (IFN) production and antiviral immunity. Here, we report that the influenza A virus nonstructural protein 1 (NS1) specifically inhibits TRIM25-mediated RIG-I CARD ubiquitination, thereby suppressing RIG-I signal transduction. A novel domain in NS1 comprising E96/E97 residues mediates its interaction with the coiled-coil domain of TRIM25, thus blocking TRIM25 multimerization and RIG-I CARD domain ubiquitination. Furthermore, a recombinant influenza A virus expressing an E96A/E97A NS1 mutant is defective in blocking TRIM25-mediated antiviral IFN response and loses virulence in mice. Our findings reveal a mechanism by which influenza virus inhibits host IFN response and also emphasize the vital role of TRIM25 in modulating antiviral defenses.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Immune evasion by hepatitis C virus NS3/4A protease-mediated cleavage of the Toll-like receptor 3 adaptor protein TRIF.

            Toll-like receptors (TLRs) bind pathogen-specific ligands early in infection, initiating signaling pathways that lead to expression of multiple protective cellular genes. Many viruses have evolved strategies that block the effector mechanisms induced through these signaling pathways, but viral interference with critical proximal receptor interactions has not been described. We show here that the NS3/4A serine protease of hepatitis C virus (HCV), a virus notorious for its ability to establish persistent intrahepatic infection, causes specific proteolysis of Toll-IL-1 receptor domain-containing adaptor inducing IFN-beta (TRIF or TICAM-1), an adaptor protein linking TLR3 to kinases responsible for activating IFN regulatory factor 3 (IRF-3) and NF-kappaB, transcription factors controlling a multiplicity of antiviral defenses. NS3/4A-mediated cleavage of TRIF reduces its abundance and inhibits polyI:C-activated signaling through the TLR3 pathway before its bifurcation to IRF-3 and NF-kappaB. This uniquely broad mechanism of immune evasion potentially limits expression of multiple host defense genes, thereby promoting persistent infections with this medically important virus.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Mitochondrial-associated endoplasmic reticulum membranes (MAM) form innate immune synapses and are targeted by hepatitis C virus.

              RIG-I is a cytosolic pathogen recognition receptor that engages viral RNA in infected cells to trigger innate immune defenses through its adaptor protein MAVS. MAVS resides on mitochondria and peroxisomes, but how its signaling is coordinated among these organelles has not been defined. Here we show that a major site of MAVS signaling is the mitochondrial-associated membrane (MAM), a distinct membrane compartment that links the endoplasmic reticulum to mitochondria. During RNA virus infection, RIG-I is recruited to the MAM to bind MAVS. Dynamic MAM tethering to mitochondria and peroxisomes then coordinates MAVS localization to form a signaling synapse between membranes. Importantly, the hepatitis C virus NS3/4A protease, which cleaves MAVS to support persistent infection, targets this synapse for MAVS proteolysis from the MAM, but not from mitochondria, to ablate RIG-I signaling of immune defenses. Thus, the MAM mediates an intracellular immune synapse that directs antiviral innate immunity.
                Bookmark

                Author and article information

                Contributors
                Journal
                Curr Opin Microbiol
                Curr. Opin. Microbiol
                Current Opinion in Microbiology
                Elsevier Ltd.
                1369-5274
                1879-0364
                8 June 2016
                August 2016
                8 June 2016
                : 32
                : 113-119
                Affiliations
                [1 ]Department of Molecular Genetics & Microbiology, Duke University Medical Center, Durham, NC 27710, USA
                [2 ]Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
                Article
                S1369-5274(16)30070-4
                10.1016/j.mib.2016.05.015
                4983539
                27288760
                cda980e5-8eb1-4601-a977-adff963ee6a4
                © 2016 Elsevier Ltd. All rights reserved.

                Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

                History
                Categories
                Article

                Microbiology & Virology
                Microbiology & Virology

                Comments

                Comment on this article