1
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Badu P, Baniulyte G, Sammons MA, Pager CT. Activation of ATF3 via the Integrated Stress Response Pathway Regulates Innate Immune Response to Restrict Zika Virus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.07.26.550716. [PMID: 37546954 PMCID: PMC10402074 DOI: 10.1101/2023.07.26.550716] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Zika virus (ZIKV) is a re-emerging mosquito-borne flavivirus that can have devastating health consequences. The developmental and neurological effects from a ZIKV infection arise in part from the virus triggering cellular stress pathways and perturbing transcriptional programs. To date, the underlying mechanisms of transcriptional control directing viral restriction and virus-host interaction are understudied. Activating Transcription Factor 3 (ATF3) is a stress-induced transcriptional effector that modulates the expression of genes involved in a myriad of cellular processes, including inflammation and antiviral responses, to restore cellular homeostasis. While ATF3 is known to be upregulated during ZIKV infection, the mode by which ATF3 is activated and the specific role of ATF3 during ZIKV infection is unknown. In this study, we show via inhibitor and RNA interference approaches that ZIKV infection initiates the integrated stress response pathway to activate ATF4 which in turn induces ATF3 expression. Additionally, by using CRISPR-Cas9 system to delete ATF3, we found that ATF3 acts to limit ZIKV gene expression in A549 cells. We also determined that ATF3 enhances the expression of antiviral genes such as STAT1 and other components in the innate immunity pathway to induce an ATF3-dependent anti-ZIKV response. Our study reveals crosstalk between the integrated stress response and innate immune response pathways and highlights an important role for ATF3 in establishing an antiviral effect during ZIKV infection.
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Affiliation(s)
- Pheonah Badu
- Department of Biological Sciences, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
- The RNA Institute, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
| | - Gabriele Baniulyte
- Department of Biological Sciences, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
- The RNA Institute, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
| | - Morgan A. Sammons
- Department of Biological Sciences, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
- The RNA Institute, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
| | - Cara T. Pager
- Department of Biological Sciences, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
- The RNA Institute, College of Arts and Sciences, University at Albany-SUNY, Albany, NY 12222
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2
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Pallarés HM, González López Ledesma MM, Oviedo-Rouco S, Castellano LA, Costa Navarro GS, Fernández-Alvarez AJ, D'Andreiz MJ, Aldas-Bulos VD, Alvarez DE, Bazzini AA, Gamarnik AV. Zika virus non-coding RNAs antagonize antiviral responses by PKR-mediated translational arrest. Nucleic Acids Res 2024:gkae507. [PMID: 38917323 DOI: 10.1093/nar/gkae507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 05/08/2024] [Accepted: 06/04/2024] [Indexed: 06/27/2024] Open
Abstract
Zika virus (ZIKV) is an emerging mosquito-borne flavivirus that causes severe outbreaks in human populations. ZIKV infection leads to the accumulation of small non-coding viral RNAs (known as sfRNAs) that are crucial for evasion of antiviral responses and for viral pathogenesis. However, the mechanistic understanding of how sfRNAs function remains incomplete. Here, we use recombinant ZIKVs and ribosome profiling of infected human cells to show that sfRNAs block translation of antiviral genes. Mechanistically, we demonstrate that specific RNA structures present in sfRNAs trigger PKR activation, which instead of limiting viral replication, enhances viral particle production. Although ZIKV infection induces mRNA expression of antiviral genes, translation efficiency of type I interferon and interferon stimulated genes were significantly downregulated by PKR activation. Our results reveal a novel viral adaptation mechanism mediated by sfRNAs, where ZIKV increases its fitness by repurposing the antiviral role of PKR into a proviral factor.
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Affiliation(s)
- Horacio M Pallarés
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires IIBBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - María Mora González López Ledesma
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires IIBBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Santiago Oviedo-Rouco
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires IIBBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | | | - Guadalupe S Costa Navarro
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires IIBBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Ana J Fernández-Alvarez
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires IIBBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - María Josefina D'Andreiz
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires IIBBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | | | - Diego E Alvarez
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín-CONICET, Buenos Aires, Argentina
| | - Ariel A Bazzini
- Stowers Institute for Medical Research, Kansas City, MO, USA
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Blvd, Kansas City, KS 66160, USA
| | - Andrea V Gamarnik
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires IIBBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
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3
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Lee J, Ou JHJ. HCV-induced autophagy and innate immunity. Front Immunol 2024; 15:1305157. [PMID: 38370419 PMCID: PMC10874285 DOI: 10.3389/fimmu.2024.1305157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/19/2024] [Indexed: 02/20/2024] Open
Abstract
The interplay between autophagy and host innate immunity has been of great interest. Hepatitis C virus (HCV) impedes signaling pathways initiated by pattern-recognition receptors (PRRs) that recognize pathogens-associated molecular patterns (PAMPs). Autophagy, a cellular catabolic process, delivers damaged organelles and protein aggregates to lysosomes for degradation and recycling. Autophagy is also an innate immune response of cells to trap pathogens in membrane vesicles for removal. However, HCV controls the autophagic pathway and uses autophagic membranes to enhance its replication. Mitophagy, a selective autophagy targeting mitochondria, alters the dynamics and metabolism of mitochondria, which play important roles in host antiviral responses. HCV also alters mitochondrial dynamics and promotes mitophagy to prevent premature cell death and attenuate the interferon (IFN) response. In addition, the dysregulation of the inflammasomal response by HCV leads to IFN resistance and immune tolerance. These immune evasion properties of HCV allow HCV to successfully replicate and persist in its host cells. In this article, we discuss HCV-induced autophagy/mitophagy and its associated immunological responses and provide a review of our current understanding of how these processes are regulated in HCV-infected cells.
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Affiliation(s)
| | - J.-H. James Ou
- Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, Los Angeles, CA, United States
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4
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Lange F, Garn J, Anagho HA, Vondran FWR, von Hahn T, Pietschmann T, Carpentier A. Hepatitis D virus infection, innate immune response and antiviral treatments in stem cell-derived hepatocytes. Liver Int 2023; 43:2116-2129. [PMID: 37366005 DOI: 10.1111/liv.15655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 06/01/2023] [Accepted: 06/12/2023] [Indexed: 06/28/2023]
Abstract
BACKGROUND Human pluripotent stem cell (hPSC)-derived hepatocyte-like cells (HLCs) are a valuable model to investigate host-pathogen interactions of hepatitis viruses in a mature and authentic environment. Here, we investigate the susceptibility of HLCs to the hepatitis delta virus (HDV). METHODS We differentiated hPSC into HLCs, and inoculated them with infectious HDV produced in Huh7NTCP . HDV infection and cellular response was monitored by RTqPCR and immunostaining. RESULTS Cells undergoing hepatic differentiation become susceptible to HDV after acquiring expression of the viral receptor Na+ -taurocholate co-transporting polypeptide (NTCP) during hepatic specification. Inoculation of HLCs with HDV leads to detection of intracellular HDV RNA and accumulation of the HDV antigen in the cells. Upon infection, the HLCs mounted an innate immune response based on induction of the interferons IFNB and L, and upregulation of interferon-stimulated genes. The intensity of this immune response positively correlated with the level of viral replication and was dependant on both the JAK/STAT and NFκB pathway activation. Importantly, this innate immune response did not inhibit HDV replication. However, pre-treatment of the HLCs with IFNα2b reduced viral infection, suggesting that ISGs may limit early stages of infection. Myrcludex efficiently abrogated infection and blocked innate immune activation. Lonafarnib treatment of HDV mono infected HLCs on the other hand led to exacerbated viral replication and innate immune response. CONCLUSION The HDV in vitro mono-infection model represents a new tool to study HDV replication, its host-pathogen interactions and evaluate new antiviral drugs in cells displaying mature hepatic functions.
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Affiliation(s)
- Frauke Lange
- Institute for Experimental Virology, TWINCORE Centre for Experimental and Clinical Infection Research, a joint venture between Medical School Hannover (MHH) and Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Jonathan Garn
- Institute for Experimental Virology, TWINCORE Centre for Experimental and Clinical Infection Research, a joint venture between Medical School Hannover (MHH) and Helmholtz Centre for Infection Research (HZI), Hannover, Germany
| | - Holda A Anagho
- Institute for Experimental Virology, TWINCORE Centre for Experimental and Clinical Infection Research, a joint venture between Medical School Hannover (MHH) and Helmholtz Centre for Infection Research (HZI), Hannover, Germany
- Institut für Molekularbiologie, Medizinische Hochschule Hannover, Hannover, Germany
- Klinik für Gastroenterologie, Hepatologie und Endokrinologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Florian W R Vondran
- ReMediES, Department of General, Visceral and Transplant Surgery, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Hannover, Germany
| | - Thomas von Hahn
- Institut für Molekularbiologie, Medizinische Hochschule Hannover, Hannover, Germany
- Klinik für Gastroenterologie, Hepatologie und Endokrinologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Thomas Pietschmann
- Institute for Experimental Virology, TWINCORE Centre for Experimental and Clinical Infection Research, a joint venture between Medical School Hannover (MHH) and Helmholtz Centre for Infection Research (HZI), Hannover, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Arnaud Carpentier
- Institute for Experimental Virology, TWINCORE Centre for Experimental and Clinical Infection Research, a joint venture between Medical School Hannover (MHH) and Helmholtz Centre for Infection Research (HZI), Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
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5
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Chaumont L, Collet B, Boudinot P. Protein kinase double-stranded RNA-dependent (PKR) in antiviral defence in fish and mammals. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2023; 145:104732. [PMID: 37172664 DOI: 10.1016/j.dci.2023.104732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/07/2023] [Accepted: 05/09/2023] [Indexed: 05/15/2023]
Abstract
The interferon-inducible double-stranded RNA-dependent protein kinase (PKR) is one of the key antiviral arms of the innate immune system. Upon binding of viral double stranded RNA, a viral Pattern Associated Molecular Pattern (PAMP), PKR gets activated and phosphorylates the eukaryotic initiation factor 2α (eIF2α) resulting in a protein shut-down that limits viral replication. Since its discovery in the mid-seventies, PKR has been shown to be involved in multiple important cellular processes including apoptosis, proinflammatory and innate immune responses. Viral subversion mechanisms of PKR underline its importance in the antiviral response of the host. PKR activation pathways and its mechanisms of action were previously identified and characterised mostly in mammalian models. However, fish Pkr and fish-specific paralogue Z-DNA-dependent protein kinase (Pkz) also play key role in antiviral defence. This review gives an update on the current knowledge on fish Pkr/Pkz, their conditions of activation and their implication in the immune responses to viruses, in comparison to their mammalian counterparts.
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Affiliation(s)
- Lise Chaumont
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, 78350, France
| | - Bertrand Collet
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, 78350, France
| | - Pierre Boudinot
- Université Paris-Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, 78350, France.
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6
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Malekshahi A, Alamdary A, Safarzadeh A, Khavandegar A, Nikoo HR, Safavi M, Ajorloo M, Bahavar A, Ajorloo M. Potential roles of core and core+1 proteins during the chronic phase of hepatitis C virus infection. Future Virol 2023. [DOI: 10.2217/fvl-2022-0117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
The HCV Core protein is a multifunctional protein that interacts with many viral and cellular proteins. In addition to the encapsidation of the viral genome, it can disturb various cellular pathways and impede antiviral cellular responses such as interferon (IFN) production. The Core protein can also disrupt the functions of immune cells against HCV. The Core protein helps viral infection persistency by interfering with apoptosis. The Core+1 protein plays a significant role in inducing chronic HCV infection through diverse mechanisms. We review some of the mechanisms by which Core and Core+1 proteins facilitate HCV infection to chronic infection. These proteins could be considered for designing more sufficient treatments and effective vaccines against HCV.
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Affiliation(s)
- Asra Malekshahi
- Student Research Committee, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Ashkan Alamdary
- Department of Biology, Science & Research Branch, Islamic Azad University, Tehran, Iran
| | - Ali Safarzadeh
- Department of Biology, University of Padova, Padova, Italy
| | - Armin Khavandegar
- Student Research Committee, Alborz University of Medical Sciences, Karaj, Iran
| | - Hadi Razavi Nikoo
- Infectious Disease Research Center, Golestan University of Medical Sciences, Gorgan, Iran
- Department of Microbiology, Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran
| | - Mahshid Safavi
- Student Research Committee, Alborz University of Medical Sciences, Karaj, Iran
| | - Mobina Ajorloo
- Student Research Committee, Alborz University of Medical Sciences, Karaj, Iran
| | - Atefeh Bahavar
- Department of Microbiology, Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran
| | - Mehdi Ajorloo
- Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran
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7
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Chen S, Harris M. NS5A domain I antagonises PKR to facilitate the assembly of infectious hepatitis C virus particles. PLoS Pathog 2023; 19:e1010812. [PMID: 36795772 PMCID: PMC9977016 DOI: 10.1371/journal.ppat.1010812] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 03/01/2023] [Accepted: 02/02/2023] [Indexed: 02/17/2023] Open
Abstract
Hepatitis C virus NS5A is a multifunctional phosphoprotein comprised of three domains (DI, DII and DIII). DI and DII have been shown to function in genome replication, whereas DIII has a role in virus assembly. We previously demonstrated that DI in genotype 2a (JFH1) also plays a role in virus assembly, exemplified by the P145A mutant which blocked infectious virus production. Here we extend this analysis to identify two other conserved and surface exposed residues proximal to P145 (C142 and E191) that exhibited no defect in genome replication but impaired virus production. Further analysis revealed changes in the abundance of dsRNA, the size and distribution of lipid droplets (LD) and the co-localisation between NS5A and LDs in cells infected with these mutants, compared to wildtype. In parallel, to investigate the mechanism(s) underpinning this role of DI, we assessed the involvement of the interferon-induced double-stranded RNA-dependent protein kinase (PKR). In PKR-silenced cells, C142A and E191A exhibited levels of infectious virus production, LD size and co-localisation between NS5A and LD that were indistinguishable from wildtype. Co-immunoprecipitation and in vitro pulldown experiments confirmed that wildtype NS5A domain I (but not C142A or E191A) interacted with PKR. We further showed that the assembly phenotype of C142A and E191A was restored by ablation of interferon regulatory factor-1 (IRF1), a downstream effector of PKR. These data suggest a novel interaction between NS5A DI and PKR that functions to evade an antiviral pathway that blocks virus assembly through IRF1.
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Affiliation(s)
- Shucheng Chen
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Mark Harris
- School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
- * E-mail:
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8
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Lee J, Ou JHJ. Hepatitis C virus and intracellular antiviral response. Curr Opin Virol 2022; 52:244-249. [PMID: 34973476 PMCID: PMC8844188 DOI: 10.1016/j.coviro.2021.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 12/09/2021] [Indexed: 02/03/2023]
Abstract
To establish successful infection in cells, it is essential for hepatitis C virus (HCV) to overcome intracellular antiviral responses. The host cell mechanism that fights against the virus culminates in the production of interferons (IFNs), IFN-stimulated genes (ISGs) and pro-inflammatory cytokines as well as the induction of autophagy and apoptosis. HCV has developed multiple means to disrupt the host signaling pathways that lead to these antiviral responses. HCV impedes signaling pathways initiated by pattern-recognition receptors (PRRs), usurps and uses the antiviral autophagic response to enhance its replication, alters mitochondrial dynamics and metabolism to prevent cell death and attenuate IFN response, and dysregulates inflammasomal response to cause IFN resistance and immune tolerance. These effects of HCV allow HCV to successful replicate and persist in its host cells.
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9
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Abstract
Cells respond to viral infections through sensors that detect non-self-molecules, and through effectors, which can have direct antiviral activities or adapt cell physiology to limit viral infection and propagation. Eukaryotic translation initiation factor 2 alpha kinase 2, better known as PKR, acts as both a sensor and an effector in the response to viral infections. After sensing double-stranded RNA molecules in infected cells, PKR self-activates and majorly exerts its antiviral function by blocking the translation machinery and inducing apoptosis. The antiviral potency of PKR is emphasized by the number of strategies developed by viruses to antagonize the PKR pathway. In this review, we present an update on the diversity of such strategies, which range from preventing double-stranded RNA recognition upstream from PKR activation, to activating eIF2B downstream from PKR targets.
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Affiliation(s)
- Teresa Cesaro
- de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - Thomas Michiels
- de Duve Institute, Université catholique de Louvain, Brussels, Belgium
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10
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Barriocanal M, Prior C, Suarez B, Unfried JP, Razquin N, Hervás-Stubbs S, Sangro B, Segura V, Fortes P. Long Noncoding RNA EGOT Responds to Stress Signals to Regulate Cell Inflammation and Growth. THE JOURNAL OF IMMUNOLOGY 2021; 206:1932-1942. [PMID: 33789981 DOI: 10.4049/jimmunol.1900776] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 02/10/2021] [Indexed: 01/10/2023]
Abstract
The cell has several mechanisms to sense and neutralize stress. Stress-related stimuli activate pathways that counteract danger, support cell survival, and activate the inflammatory response. We use human cells to show that these processes are modulated by EGOT, a long noncoding RNA highly induced by viral infection, whose inhibition results in increased levels of antiviral IFN-stimulated genes (ISGs) and decreased viral replication. We now show that EGOT is induced in response to cell stress, viral replication, or the presence of pathogen-associated molecular patterns via the PI3K/AKT, MAPKs, and NF-κB pathways, which lead to cell survival and inflammation. Transcriptome analysis and validation experiments show that EGOT modulates PI3K/AKT and NF-κB responses. On the one hand, EGOT inhibition decreases expression of PI3K/AKT-induced cellular receptors and cell proliferation. In fact, EGOT levels are increased in several tumors. On the other hand, EGOT inhibition results in decreased levels of key NF-κB target genes, including those required for inflammation and ISGs in those cells that build an antiviral response. Mechanistically, EGOT depletion decreases the levels of the key coactivator TBLR1, essential for transcription by NF-κB. In summary, EGOT is induced in response to stress and may function as a switch that represses ISG transcription until a proper antiviral or stress response is initiated. EGOT then helps PI3K/AKT, MAPKs, and NF-κB pathways to activate the antiviral response, cell inflammation, and growth. We believe that modulation of EGOT levels could be used as a therapy for the treatment of certain viral infections, immune diseases, and cancer.
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Affiliation(s)
- Marina Barriocanal
- Program of Gene Therapy and Hepatolovgy, Center for Applied Medical Research, Pamplona, Spain.,Liver Unit, Clínica Universidad de Navarra (CUN) 31008, Pamplona, Spain
| | - Celia Prior
- Program of Gene Therapy and Hepatolovgy, Center for Applied Medical Research, Pamplona, Spain.,Liver Unit, Clínica Universidad de Navarra (CUN) 31008, Pamplona, Spain
| | - Beatriz Suarez
- Program of Gene Therapy and Hepatolovgy, Center for Applied Medical Research, Pamplona, Spain
| | - Juan Pablo Unfried
- Program of Gene Therapy and Hepatolovgy, Center for Applied Medical Research, Pamplona, Spain
| | - Nerea Razquin
- Program of Gene Therapy and Hepatolovgy, Center for Applied Medical Research, Pamplona, Spain
| | - Sandra Hervás-Stubbs
- Program of Immunology and Immunotherapy, Center for Applied Medical Research, University of Navarra, 31008 Pamplona, Spain.,Navarra Institute for Health Research, 31008 Pamplona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Pamplona, Spain; and
| | - Bruno Sangro
- Liver Unit, Clínica Universidad de Navarra (CUN) 31008, Pamplona, Spain.,Navarra Institute for Health Research, 31008 Pamplona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Pamplona, Spain; and
| | - Victor Segura
- Navarra Institute for Health Research, 31008 Pamplona, Spain.,Bioinformatics Platform, Center for Applied Medical Research, University of Navarra, 31008 Pamplona, Spain
| | - Puri Fortes
- Program of Gene Therapy and Hepatolovgy, Center for Applied Medical Research, Pamplona, Spain; .,Navarra Institute for Health Research, 31008 Pamplona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Pamplona, Spain; and
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11
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The Inflammasome Components NLRP3 and ASC Act in Concert with IRGM To Rearrange the Golgi Apparatus during Hepatitis C Virus Infection. J Virol 2021; 95:JVI.00826-20. [PMID: 33208442 PMCID: PMC7925091 DOI: 10.1128/jvi.00826-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 10/30/2020] [Indexed: 12/18/2022] Open
Abstract
Numerous pathogens can affect cellular homeostasis and organelle dynamics. Hepatitis C virus (HCV) triggers Golgi fragmentation through the immunity-related GTPase M (IRGM), a resident Golgi protein, to enhance its lipid supply for replication. Hepatitis C virus (HCV) infection triggers Golgi fragmentation through the Golgi-resident protein immunity-related GTPase M (IRGM). Here, we report the roles of NLRP3 (NOD-, LRR- and pyrin domain-containing protein 3) and ASC (apoptosis-associated speck-like protein containing a caspase activation and recruitment domain [CARD]), two inflammasome components, in the initial events leading to this fragmentation. We show that ASC resides at the Golgi with IRGM at homeostasis. Upon infection, ASC dissociates from both IRGM and the Golgi and associates with HCV-induced NLRP3. NLRP3 silencing inhibits Golgi fragmentation. ASC silencing disrupts the Golgi structure in both control and infected cells and reduces the localization of IRGM at the Golgi. IRGM depletion in the ASC-silenced cells cannot totally restore the Golgi structure. These data highlight a role for ASC, upstream of the formation of the inflammasome, in regulating IRGM through its control on the Golgi. A similar mechanism occurs in response to nigericin treatment, but not in cells infected with another member of the Flaviviridae family, Zika virus (ZIKV). We propose a model for a newly ascribed function of the inflammasome components in Golgi structural remodeling during certain stimuli. IMPORTANCE Numerous pathogens can affect cellular homeostasis and organelle dynamics. Hepatitis C virus (HCV) triggers Golgi fragmentation through the immunity-related GTPase M (IRGM), a resident Golgi protein, to enhance its lipid supply for replication. Here, we reveal the role of the inflammasome components NLRP3 and ASC in this process, thus uncovering a new interplay between effectors of inflammation and viral infection or stress. We show that the inflammasome component ASC resides at the Golgi under homeostasis and associates with IRGM. Upon HCV infection, ASC is recruited to NLRP3 and dissociates from IRGM, causing Golgi fragmentation. Our results uncover that aside from their known function in the inflammation response, these host defense regulators also ensure the maintenance of intact intracellular structure in homeostasis, while their activation relieves factors leading to Golgi remodeling.
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12
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Sokolova TM. [Hepatitis C virus (Flaviviridae: Hepacivirus: Hepacivirus C): regulation of signaling reactions of innate immunity]. Vopr Virusol 2021; 65:307-316. [PMID: 33533227 DOI: 10.36233/0507-4088-2020-65-6-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 01/07/2021] [Indexed: 12/21/2022]
Abstract
Studying the regulation of signaling reactions of innate immunity by the hepatitis C virus (HCV) will help to reveal the causes of the transition of the acute form of the disease to a chronic course. The molecular mechanisms of activation by HCV RNA of innate immunity receptors TLR and RLR and signal transduction processes leading to the synthesis of IFN and inflammatory cytokines are considered. The inhibitory effects of non-structural and structural HCV proteins on immune signaling reactions are analyzed in detail. The information presented is the result of an analysis of literature data published in international databases mainly over the past 5 years. In conclusion, signaling receptors are proposed as targets for the development of new antiviral drugs with immunotherapeutic activity.
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Affiliation(s)
- T M Sokolova
- D.I. Ivanovsky Institute of Virology of National Research Centre for Epidemiology and Microbiology named after the honorary academician N.F. Gamaleya
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13
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Carpentier A, Sheldon J, Vondran FWR, Brown RJ, Pietschmann T. Efficient acute and chronic infection of stem cell-derived hepatocytes by hepatitis C virus. Gut 2020; 69:1659-1666. [PMID: 32114504 PMCID: PMC7456736 DOI: 10.1136/gutjnl-2019-319354] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVE AND DESIGN Human stem cell-derived hepatocyte-like cells (HLCs) have shown high potential as authentic model for dissection of the HCV life cycle and virus-induced pathogenesis. However, modest HCV replication, possibly due to robust innate immune responses, limits their broader use. To overcome these limitations and to dissect the mechanisms responsible for control of HCV, we analysed expression of key components of the interferon (IFN) system in HLCs, assessed permissiveness for different HCV strains and blocked innate immune signalling by pharmacological intervention. RESULTS Transcriptional profiling revealed that HLCs constitutively express messenger RNA of RLRs, and members of the IFN pathway. Moreover, HLCs upregulated IFNs and canonical interferon-regulated genes (IRGs) upon transfection with the double-stranded RNA mimic poly(I:C). Infection of HLCs with Jc1-HCVcc produced only limited viral progeny. In contrast, infection with p100, a Jc1-derived virus population with enhanced replication fitness and partial resistance to IFN, resulted in robust yet transient viraemia. Viral titres declined concomitant with a peak of IRG induction. Addition of ruxolitinib, a JAK/STAT inhibitor, permitted chronic infection and raised p100 infectious virus titres to 1×105 FFU/mL. IRGs expression profiling in infected HLCs revealed a landscape of HCV-dependent transcriptional changes similar to HCV-infected primary human hepatocytes, but distinct from Huh-7.5 cells. Withdrawal of ruxolitinib restored innate immune responses and resulted in HCV clearance. CONCLUSION This authentic human cell model is well suited to examine acute and chronic host-HCV interactions, particularly IFN-triggered antiviral effector functions and mechanisms of innate immune control of HCV infection.
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Affiliation(s)
- Arnaud Carpentier
- Institute of Experimental Virology, Twincore, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Julie Sheldon
- Institute of Experimental Virology, Twincore, Hannover, Germany
| | - Florian W R Vondran
- ReMediES, Department of General, Visceral and Transplant Surgery, Hannover Medical School, Hannover, Germany
- German Centre for Infection Research (DZIF), partner site Hannover-Braunschweig, Germany
| | - Richard Jp Brown
- Institute of Experimental Virology, Twincore, Hannover, Germany
- Division of Veterinary Medicine, Paul-Ehrlich-Institut, Langen, Germany
| | - Thomas Pietschmann
- Institute of Experimental Virology, Twincore, Hannover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- German Centre for Infection Research (DZIF), partner site Hannover-Braunschweig, Germany
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14
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Liu Y, Wang M, Cheng A, Yang Q, Wu Y, Jia R, Liu M, Zhu D, Chen S, Zhang S, Zhao XX, Huang J, Mao S, Ou X, Gao Q, Wang Y, Xu Z, Chen Z, Zhu L, Luo Q, Liu Y, Yu Y, Zhang L, Tian B, Pan L, Rehman MU, Chen X. The role of host eIF2α in viral infection. Virol J 2020; 17:112. [PMID: 32703221 PMCID: PMC7376328 DOI: 10.1186/s12985-020-01362-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 06/23/2020] [Indexed: 12/24/2022] Open
Abstract
Background eIF2α is a regulatory node that controls protein synthesis initiation by its phosphorylation or dephosphorylation. General control nonderepressible-2 (GCN2), protein kinase R-like endoplasmic reticulum kinase (PERK), double-stranded RNA (dsRNA)-dependent protein kinase (PKR) and heme-regulated inhibitor (HRI) are four kinases that regulate eIF2α phosphorylation. Main body In the viral infection process, dsRNA or viral proteins produced by viral proliferation activate different eIF2α kinases, resulting in eIF2α phosphorylation, which hinders ternary tRNAMet-GTP-eIF2 complex formation and inhibits host or viral protein synthesis. The stalled messenger ribonucleoprotein (mRNP) complex aggregates under viral infection stress to form stress granules (SGs), which encapsulate viral RNA and transcription- and translation-related proteins, thereby limiting virus proliferation. However, many viruses have evolved a corresponding escape mechanism to synthesize their own proteins in the event of host protein synthesis shutdown and SG formation caused by eIF2α phosphorylation, and viruses can block the cell replication cycle through the PERK-eIF2α pathway, providing a favorable environment for their own replication. Subsequently, viruses can induce host cell autophagy or apoptosis through the eIF2α-ATF4-CHOP pathway. Conclusions This review summarizes the role of eIF2α in viral infection to provide a reference for studying the interactions between viruses and hosts.
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Affiliation(s)
- Yuanzhi Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China. .,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China. .,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Dekang Zhu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Xin-Xin Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Juan Huang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Yin Wang
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Zhiwen Xu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Zhengli Chen
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Ling Zhu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Qihui Luo
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Yunya Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Yanling Yu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Ling Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Bin Tian
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Leichang Pan
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Mujeeb Ur Rehman
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
| | - Xiaoyue Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China.,Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, P.R. China
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15
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Unfried JP, Fortes P. LncRNAs in HCV Infection and HCV-Related Liver Disease. Int J Mol Sci 2020; 21:ijms21062255. [PMID: 32214045 PMCID: PMC7139329 DOI: 10.3390/ijms21062255] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 12/14/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) are transcripts with poor coding capacity that may interact with proteins, DNA, or other RNAs to perform structural and regulatory functions. The lncRNA transcriptome changes significantly in most diseases, including cancer and viral infections. In this review, we summarize the functional implications of lncRNA-deregulation after infection with hepatitis C virus (HCV). HCV leads to chronic infection in many patients that may progress to liver cirrhosis and hepatocellular carcinoma (HCC). Most lncRNAs deregulated in infected cells that have been described function to potentiate or block the antiviral response and, therefore, they have a great impact on HCV viral replication. In addition, several lncRNAs upregulated by the infection contribute to viral release. Finally, many lncRNAs have been described as deregulated in HCV-related HCC that function to enhance cell survival, proliferation, and tumor progression by different mechanisms. Interestingly, some HCV-related HCC lncRNAs can be detected in bodily fluids, and there is great hope that they could be used as biomarkers to predict cancer initiation, progression, tumor burden, response to treatment, resistance to therapy, or tumor recurrence. Finally, there is high confidence that lncRNAs could also be used to improve the suboptimal long-term outcomes of current HCC treatment options.
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Affiliation(s)
| | - P. Fortes
- Correspondence: ; Tel.: +34-948194700
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16
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Ferreira AR, Ramos B, Nunes A, Ribeiro D. Hepatitis C Virus: Evading the Intracellular Innate Immunity. J Clin Med 2020; 9:jcm9030790. [PMID: 32183176 PMCID: PMC7141330 DOI: 10.3390/jcm9030790] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 03/02/2020] [Accepted: 03/04/2020] [Indexed: 12/25/2022] Open
Abstract
Hepatitis C virus (HCV) infections constitute a major public health problem and are the main cause of chronic hepatitis and liver disease worldwide. The existing drugs, while effective, are expensive and associated with undesirable secondary effects. There is, hence, an urgent need to develop novel therapeutics, as well as an effective vaccine to prevent HCV infection. Understanding the interplay between HCV and the host cells will certainly contribute to better comprehend disease progression and may unravel possible new cellular targets for the development of novel antiviral therapeutics. Here, we review and discuss the interplay between HCV and the host cell innate immunity. We focus on the different cellular pathways that respond to, and counteract, HCV infection and highlight the evasion strategies developed by the virus to escape this intracellular response.
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Affiliation(s)
| | | | | | - Daniela Ribeiro
- Correspondence: ; Tel.: +351-234-247-014; Fax: +351-234-372-587
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17
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Gokhale NS, McIntyre ABR, Mattocks MD, Holley CL, Lazear HM, Mason CE, Horner SM. Altered m 6A Modification of Specific Cellular Transcripts Affects Flaviviridae Infection. Mol Cell 2020; 77:542-555.e8. [PMID: 31810760 PMCID: PMC7007864 DOI: 10.1016/j.molcel.2019.11.007] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 10/11/2019] [Accepted: 10/29/2019] [Indexed: 02/07/2023]
Abstract
The RNA modification N6-methyladenosine (m6A) modulates mRNA fate and thus affects many biological processes. We analyzed m6A across the transcriptome following infection by dengue virus (DENV), Zika virus (ZIKV), West Nile virus (WNV), and hepatitis C virus (HCV). We found that infection by these viruses in the Flaviviridae family alters m6A modification of specific cellular transcripts, including RIOK3 and CIRBP. During viral infection, the addition of m6A to RIOK3 promotes its translation, while loss of m6A in CIRBP promotes alternative splicing. Importantly, viral activation of innate immune sensing or the endoplasmic reticulum (ER) stress response contributes to the changes in m6A in RIOK3 or CIRBP, respectively. Further, several transcripts with infection-altered m6A profiles, including RIOK3 and CIRBP, encode proteins that influence DENV, ZIKV, and HCV infection. Overall, this work reveals that cellular signaling pathways activated during viral infection lead to alterations in m6A modification of host mRNAs to regulate infection.
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Affiliation(s)
- Nandan S Gokhale
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27705, USA
| | - Alexa B R McIntyre
- Department of Physiology and Biophysics and the Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10065, USA; Tri-Institutional Program in Computational Biology and Medicine, New York, NY 10065, USA
| | - Melissa D Mattocks
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Christopher L Holley
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27705, USA; Department of Medicine, Duke University Medical Center, Durham, NC 27705, USA
| | - Helen M Lazear
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Christopher E Mason
- Department of Physiology and Biophysics and the Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10065, USA; The HRH Prince Alwaleed Bin Talal Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10065, USA; The WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY 10065, USA; The Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA.
| | - Stacy M Horner
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27705, USA; Department of Medicine, Duke University Medical Center, Durham, NC 27705, USA.
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18
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The Ubiquitin-Specific Protease 18 Promotes Hepatitis C Virus Production by Increasing Viral Infectivity. Mediators Inflamm 2019; 2019:3124745. [PMID: 31871427 PMCID: PMC6906844 DOI: 10.1155/2019/3124745] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/13/2019] [Accepted: 10/03/2019] [Indexed: 02/07/2023] Open
Abstract
Background and Aims Ubiquitin-specific protease 18 (USP18) is involved in immunoregulation and response to interferon- (IFN-) based treatment in patients chronically infected with hepatitis C virus (HCV). We investigated whether and how its upregulation alters HCV infection. Methods Overexpression of wild-type (USP18 WT) or catalytically inactive mutant (USP18 C64S) USP18 was examined for effects on HCV replication in the absence and presence of IFNα or IFNλ using both the HCV-infective model and replicon cells. The IFN signaling pathway was assessed via STAT1 phosphorylation (western blot) and downstream ISG expression (real-time PCR). Mechanistic roles were sought by quantifying microRNA-122 levels and J6/JFH1 infectivity of Huh7.5 cells. Results We found that overexpression of either USP18 WT or USP18 C64S stimulated HCV production and blunted the anti-HCV effect of IFNα and IFNλ in the infective model but not in the replicon system. Overexpressed USP18 showed no effect on Jak/STAT signaling nor on microRNA-122 expression. However, USP18 upregulation markedly increased J6/JFH1 infectivity and promoted the expression of the key HCV entry factor CD81 on Huh7.5 cells. Conclusions USP18 stimulates HCV production and blunts the effect of both type I and III IFNs by fostering a cellular environment characterized by upregulation of CD81, promoting virus entry and infectivity.
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19
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Suzuki R, Matsuda M, Shimoike T, Watashi K, Aizaki H, Kato T, Suzuki T, Muramatsu M, Wakita T. Activation of protein kinase R by hepatitis C virus RNA-dependent RNA polymerase. Virology 2019; 529:226-233. [PMID: 30738360 DOI: 10.1016/j.virol.2019.01.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/28/2019] [Accepted: 01/29/2019] [Indexed: 12/12/2022]
Abstract
Hepatitis C virus (HCV) was shown to activate protein kinase R (PKR), which inhibits expression of interferon (IFN) and IFN-stimulated genes by controlling the translation of newly transcribed mRNAs. However, it is unknown exactly how HCV activates PKR. To address the molecular mechanism(s) of PKR activation mediated by HCV infection, we examined the effects of viral proteins on PKR activation. Here, we show that expression of HCV NS5B strongly induced PKR and eIF2α phosphorylation, and attenuated MHC class I expression. In contrast, expression of Japanese encephalitis virus RNA-dependent RNA polymerase did not induce phosphorylation of PKR. Co-immunoprecipitation analyses showed that HCV NS5B interacted with PKR. Furthermore, expression of NS5B with polymerase activity-deficient mutation failed to phosphorylate PKR, suggesting that RNA polymerase activity is required for PKR activation. These results suggest that HCV activates PKR by association with NS5B, resulting in translational suppression of MHC class I to establish chronic infection.
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Affiliation(s)
- Ryosuke Suzuki
- Department of Virology II, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan; Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-murayama-shi, Tokyo 208-0011, Japan.
| | - Mami Matsuda
- Department of Virology II, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Takashi Shimoike
- Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashi-murayama-shi, Tokyo 208-0011, Japan.
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Hideki Aizaki
- Department of Virology II, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Takanobu Kato
- Department of Virology II, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Tetsuro Suzuki
- Department of Infectious Diseases, Hamamatsu University School of Medicine, Shizuoka, Japan.
| | - Masamichi Muramatsu
- Department of Virology II, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
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20
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Sarkis S, Dabo S, Lise MC, Neuveut C, Meurs EF, Lacoste V, Lavergne A. A potential robust antiviral defense state in the common vampire bat: Expression, induction and molecular characterization of the three interferon-stimulated genes -OAS1, ADAR1 and PKR. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 85:95-107. [PMID: 29635006 DOI: 10.1016/j.dci.2018.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/06/2018] [Accepted: 04/06/2018] [Indexed: 06/08/2023]
Abstract
Bats are known to harbor many zoonotic viruses, some of which are pathogenic to other mammals while they seem to be harmless in bats. As the interferon (IFN) response represents the first line of defense against viral infections in mammals, it is hypothesized that activation of the IFN system is one of the mechanisms enabling bats to co-exist with viruses. We have previously reported induction of type I IFN in a cell line from the common vampire bat, Desmodus rotundus, upon polyinosinic:polycytidylic acid (poly(I:C)) stimulation. To deepen our knowledge on D. rotundus' IFN-I antiviral response, we molecularly characterized three interferon-stimulated genes (ISGs), OAS1, PKR and ADAR1, closely implicated in the IFN-I antiviral response, and tested their functionality in our cellular model. We first found that D. rotundus encoded two OAS1 paralogs, OAS1a and OAS1b, and that the functional domains of the four ISGs characterized were highly conserved with those of other mammals. Despite their significant transcription level in the absence of stimulation, the transcription of the four ISGs characterized was enhanced by poly(I:C). In addition, the transcription of OAS1a and OAS1b appears to be differentially regulated. These findings demonstrate an active ISG antiviral response in D. rotundus in which OAS1b may play an important role.
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Affiliation(s)
- Sarkis Sarkis
- Laboratoire des Interactions Virus-Hôtes, Institut Pasteur de la Guyane, Cayenne, French Guiana.
| | - Stéphanie Dabo
- Hepacivirus and Innate Immunity, Institut Pasteur, 75015 Paris, France
| | - Marie-Claude Lise
- Laboratoire des Interactions Virus-Hôtes, Institut Pasteur de la Guyane, Cayenne, French Guiana
| | - Christine Neuveut
- Hepacivirus and Innate Immunity, Institut Pasteur, 75015 Paris, France
| | - Eliane F Meurs
- Hepacivirus and Innate Immunity, Institut Pasteur, 75015 Paris, France
| | - Vincent Lacoste
- Laboratoire des Interactions Virus-Hôtes, Institut Pasteur de la Guyane, Cayenne, French Guiana
| | - Anne Lavergne
- Laboratoire des Interactions Virus-Hôtes, Institut Pasteur de la Guyane, Cayenne, French Guiana.
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21
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Liu WJ, Yang YT, Huang YM, zhou DR, Xu DN, Cao N, Jiang DL, Pan JQ, Tian YB. Identification of Goose PKR Gene: Structure, Expression Profiling, and Antiviral Activity Against Newcastle Disease Virus. J Interferon Cytokine Res 2018; 38:333-340. [DOI: 10.1089/jir.2018.0025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Wen-jun Liu
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, China
| | - You-tian Yang
- College of Medicine, Foshan University, Foshan, China
| | - Yun-mao Huang
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, China
| | - De-Rong zhou
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
| | - Dan-ning Xu
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, China
| | - Nan Cao
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, China
| | - Dan-li Jiang
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, China
| | - Jian-qiu Pan
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, China
| | - Yun-bo Tian
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, China
- Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, China
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22
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ADAR1 affects HCV infection by modulating innate immune response. Antiviral Res 2018; 156:116-127. [PMID: 29906476 DOI: 10.1016/j.antiviral.2018.05.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 02/06/2023]
Abstract
The hepatitis C virus (HCV) is a globally prevalent infectious pathogen. As many as 80% of people infected with HCV do not control the virus and develop a chronic infection. Response to interferon (IFN) therapy is widely variable in chronic HCV infected patients, suggesting that HCV has evolved mechanisms to suppress and evade innate immunity responsible for its control and elimination. Adenosine deaminase acting on RNA 1 (ADAR1) is a relevant factor in the regulation of the innate immune response. The loss of ADAR1 RNA-editing activity and the resulting loss of inosine bases in RNA are critical in producing aberrant RLR-mediated innate immune response, mediated by RNA sensors MDA5 and RIG-I. Here, we describe ADAR1 role as a regulator of innate and antiviral immune function in HCV infection, both in vitro and in patients. Polymorphisms within ADAR1 gene were found significantly associated to poor clinical outcome to HCV therapy and advanced liver fibrosis in a cohort of HCV and HIV-1 coinfected patients. Moreover, ADAR1 knockdown in primary macrophages and Huh7 hepatoma cells enhanced IFN and IFN stimulated gene expression and increased HCV replication in vitro. Overall, our results demonstrate that ADAR1 regulates innate immune signaling and is an important contributor to the outcome of the HCV virus-host interaction. ADAR1 is a potential target to boost antiviral immune response in HCV infection.
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Liao X, Wang Y, Ye H, Li S, Chen L, Duan X. Role of interferon-stimulated genes in regulation of HCV infection and type I interferon anti-HCV activity. Future Virol 2018. [DOI: 10.2217/fvl-2017-0160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
HCV chronically infects over 71 million people worldwide and is one of the leading causes of advanced liver diseases. Type I interferons (IFN-α/β) play critical role in host antiviral innate immunity. IFN-α/β exerts its anti-HCV effects through the activation of the JAK/STAT signaling pathway leading to the induction of a few hundred interferon-stimulated genes (ISGs). The interplay between ISG and HCV infection remains partially understood. In this review, we summarized the role of ISGs in HCV infection and interferon anti-HCV activity.
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Affiliation(s)
- Xinzhong Liao
- Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College, 610052 Chengdu, PR China
| | - Yancui Wang
- Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College, 610052 Chengdu, PR China
| | - Haiyan Ye
- Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College, 610052 Chengdu, PR China
| | - Shilin Li
- Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College, 610052 Chengdu, PR China
| | - Limin Chen
- Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College, 610052 Chengdu, PR China
| | - Xiaoqiong Duan
- Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College, 610052 Chengdu, PR China
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24
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Valadkhan S, Fortes P. Regulation of the Interferon Response by lncRNAs in HCV Infection. Front Microbiol 2018; 9:181. [PMID: 29503633 PMCID: PMC5820368 DOI: 10.3389/fmicb.2018.00181] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/26/2018] [Indexed: 12/24/2022] Open
Affiliation(s)
- Saba Valadkhan
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, OH, United States
- *Correspondence: Saba Valadkhan, Puri Fortes,
| | - Puri Fortes
- Center for Applied Medical Research, Department of Gene Therapy and Hepatology, Navarra Institute for Health Research (IdiSNA), University of Navarra, Pamplona, Spain
- *Correspondence: Saba Valadkhan, Puri Fortes,
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25
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Barriocanal M, Fortes P. Long Non-coding RNAs in Hepatitis C Virus-Infected Cells. Front Microbiol 2017; 8:1833. [PMID: 29033906 PMCID: PMC5625025 DOI: 10.3389/fmicb.2017.01833] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/06/2017] [Indexed: 12/13/2022] Open
Abstract
Hepatitis C virus (HCV) often leads to a chronic infection in the liver that may progress to steatosis, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Several viral and cellular factors are required for a productive infection and for the development of liver disease. Some of these are long non-coding RNAs (lncRNAs) deregulated in infected cells. After HCV infection, the sequence and the structure of the viral RNA genome are sensed to activate interferon (IFN) synthesis and signaling pathways. These antiviral pathways regulate transcription of several cellular lncRNAs. Some of these are also deregulated in response to viral replication. Certain viral proteins and/or viral replication can activate transcription factors such as MYC, SP1, NRF2, or HIF1α that modulate the expression of additional cellular lncRNAs. Interestingly, several lncRNAs deregulated in HCV-infected cells described so far play proviral or antiviral functions by acting as positive or negative regulators of the IFN system, while others help in the development of liver cirrhosis and HCC. The study of the structure and mechanism of action of these lncRNAs may aid in the development of novel strategies to treat infectious and immune pathologies and liver diseases such as cirrhosis and HCC.
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Affiliation(s)
| | - Puri Fortes
- Department of Gene Therapy and Hepatology, Navarra Institute for Health Research (IdiSNA), Centro de Investigación Médica Aplicada, University of Navarra, Pamplona, Spain
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26
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A Map of the Arenavirus Nucleoprotein-Host Protein Interactome Reveals that Junín Virus Selectively Impairs the Antiviral Activity of Double-Stranded RNA-Activated Protein Kinase (PKR). J Virol 2017; 91:JVI.00763-17. [PMID: 28539447 DOI: 10.1128/jvi.00763-17] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 05/12/2017] [Indexed: 11/20/2022] Open
Abstract
Arenaviruses are enveloped negative-strand RNA viruses that cause significant human disease. These viruses encode only four proteins to accomplish the viral life cycle, so each arenavirus protein likely plays unappreciated accessory roles during infection. Here we used immunoprecipitation and mass spectrometry to identify human proteins that interact with the nucleoproteins (NPs) of the Old World arenavirus lymphocytic choriomeningitis virus (LCMV) and the New World arenavirus Junín virus (JUNV) strain Candid #1. Bioinformatic analysis of the identified protein partners of NP revealed that host translation appears to be a key biological process engaged during infection. In particular, NP associates with the double-stranded RNA (dsRNA)-activated protein kinase (PKR), a well-characterized antiviral protein that inhibits cap-dependent protein translation initiation via phosphorylation of eIF2α. JUNV infection leads to increased expression of PKR as well as its redistribution to viral replication and transcription factories. Further, phosphorylation of PKR, which is a prerequisite for its ability to phosphorylate eIF2α, is readily induced by JUNV. However, JUNV prevents this pool of activated PKR from phosphorylating eIF2α, even following exposure to the synthetic dsRNA poly(I·C), a potent PKR agonist. This blockade of PKR function is highly specific, as LCMV is unable to similarly inhibit eIF2α phosphorylation. JUNV's ability to antagonize the antiviral activity of PKR appears to be complete, as silencing of PKR expression has no impact on viral propagation. In summary, we provide a detailed map of the host machinery engaged by arenavirus NPs and identify an antiviral pathway that is subverted by JUNV.IMPORTANCE Arenaviruses are important human pathogens for which FDA-approved vaccines do not exist and effective antiviral therapeutics are needed. Design of antiviral treatment options and elucidation of the mechanistic basis of disease pathogenesis will depend on an increased basic understanding of these viruses and, in particular, their interactions with the host cell machinery. Identifying host proteins critical for the viral life cycle and/or pathogenesis represents a useful strategy to uncover new drug targets. This study reveals, for the first time, the extensive human protein interactome of arenavirus nucleoproteins and uncovers a potent antiviral host protein that is neutralized during Junín virus infection. In so doing, it shows further insight into the interplay between the virus and the host innate immune response and provides an important data set for the field.
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27
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Hepatitis C virus triggers Golgi fragmentation and autophagy through the immunity-related GTPase M. Proc Natl Acad Sci U S A 2017; 114:E3462-E3471. [PMID: 28389568 DOI: 10.1073/pnas.1616683114] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Positive-stranded RNA viruses, such as hepatitis C virus (HCV), assemble their viral replication complexes by remodeling host intracellular membranes to a membranous web. The precise composition of these replication complexes and the detailed mechanisms by which they are formed are incompletely understood. Here we show that the human immunity-related GTPase M (IRGM), known to contribute to autophagy, plays a previously unrecognized role in this process. We show that IRGM is localized at the Golgi apparatus and regulates the fragmentation of Golgi membranes in response to HCV infection, leading to colocalization of Golgi vesicles with replicating HCV. Our results show that IRGM controls phosphorylation of GBF1, a guanine nucleotide exchange factor for Arf-GTPases, which normally operates in Golgi membrane dynamics and vesicle coating in resting cells. We also find that HCV triggers IRGM-mediated phosphorylation of the early autophagy initiator ULK1, thereby providing mechanistic insight into the role of IRGM in HCV-mediated autophagy. Collectively, our results identify IRGM as a key Golgi-situated regulator that links intracellular membrane remodeling by autophagy and Golgi fragmentation with viral replication.
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28
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Gamil AAA, Xu C, Mutoloki S, Evensen Ø. PKR Activation Favors Infectious Pancreatic Necrosis Virus Replication in Infected Cells. Viruses 2016; 8:v8060173. [PMID: 27338445 PMCID: PMC4926193 DOI: 10.3390/v8060173] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 05/31/2016] [Accepted: 06/03/2016] [Indexed: 01/17/2023] Open
Abstract
The double-stranded RNA-activated protein kinase R (PKR) is a Type I interferon (IFN) stimulated gene that has important biological and immunological functions. In viral infections, in general, PKR inhibits or promotes viral replication, but PKR-IPNV interaction has not been previously studied. We investigated the involvement of PKR during infectious pancreatic necrosis virus (IPNV) infection using a custom-made rabbit antiserum and the PKR inhibitor C16. Reactivity of the antiserum to PKR in CHSE-214 cells was confirmed after IFNα treatment giving an increased protein level. IPNV infection alone did not give increased PKR levels by Western blot, while pre-treatment with PKR inhibitor before IPNV infection gave decreased eukaryotic initiation factor 2-alpha (eIF2α) phosphorylation. This suggests that PKR, despite not being upregulated, is involved in eIF2α phosphorylation during IPNV infection. PKR inhibitor pre-treatment resulted in decreased virus titers, extra- and intracellularly, concomitant with reduction of cells with compromised membranes in IPNV-permissive cell lines. These findings suggest that IPNV uses PKR activation to promote virus replication in infected cells.
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Affiliation(s)
- Amr A A Gamil
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 8146 Dep., 0033 Oslo, Norway.
| | - Cheng Xu
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 8146 Dep., 0033 Oslo, Norway.
| | - Stephen Mutoloki
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 8146 Dep., 0033 Oslo, Norway.
| | - Øystein Evensen
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, P.O. Box 8146 Dep., 0033 Oslo, Norway.
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29
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Kao CC, Yi G, Huang HC. The core of hepatitis C virus pathogenesis. Curr Opin Virol 2016; 17:66-73. [PMID: 26851516 DOI: 10.1016/j.coviro.2016.01.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 01/05/2016] [Accepted: 01/14/2016] [Indexed: 02/06/2023]
Abstract
Capsid proteins form protective shells around viral genomes and mediate viral entry. However, many capsid proteins have additional and important roles for virus infection and in modulating cellular response to infection, with important consequences on pathogenesis. Infection by the Hepatitis C virus (HCV) can lead to liver steatosis, cirrhosis, and hepatocellular carcinoma. Herein, we focus on the role in pathogenesis of Core, the capsid protein of the HCV.
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Affiliation(s)
- C Cheng Kao
- Dept of Molecular & Cellular Biochemistry, Indiana University, Bloomington, IN 47405, United States.
| | - Guanghui Yi
- Dept of Molecular & Cellular Biochemistry, Indiana University, Bloomington, IN 47405, United States
| | - Hsuan-Cheng Huang
- Inst. of Biomedical Informatics, National Yang-Ming University, Taipei 11221, Taiwan
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30
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Abstract
Despite advances in therapy, hepatitis C virus infection remains a major global health issue with 3 to 4 million incident cases and 170 million prevalent chronic infections. Complex, partially understood, host-virus interactions determine whether an acute infection with hepatitis C resolves, as occurs in approximately 30% of cases, or generates a persistent hepatic infection, as occurs in the remainder. Once chronic infection is established, the velocity of hepatocyte injury and resultant fibrosis is significantly modulated by immunologic as well as environmental factors. Immunomodulation has been the backbone of antiviral therapy despite poor understanding of its mechanism of action.
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Affiliation(s)
- David E. Kaplan
- Medicine and Research Services, Philadelphia VA Medical Center, Philadelphia PA,Division of Gastroenterology, Department of Medicine, University of Pennsylvania
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31
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Martínez-Esparza M, Tristán-Manzano M, Ruiz-Alcaraz AJ, García-Peñarrubia P. Inflammatory status in human hepatic cirrhosis. World J Gastroenterol 2015; 21:11522-11541. [PMID: 26556984 PMCID: PMC4631958 DOI: 10.3748/wjg.v21.i41.11522] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 07/31/2015] [Accepted: 09/30/2015] [Indexed: 02/06/2023] Open
Abstract
This review focuses on new findings about the inflammatory status involved in the development of human liver cirrhosis induced by the two main causes, hepatitis C virus (HCV) infection and chronic alcohol abuse, avoiding results obtained from animal models. When liver is faced to a persistent and/or intense local damage the maintained inflammatory response gives rise to a progressive replacement of normal hepatic tissue by non-functional fibrotic scar. The imbalance between tissue regeneration and fibrosis will determine the outcome toward health recovery or hepatic cirrhosis. In all cases progression toward liver cirrhosis is caused by a dysregulation of mechanisms that govern the balance between activation/homeostasis of the immune system. Detecting differences between the inflammatory status in HCV-induced vs alcohol-induced cirrhosis could be useful to identify specific targets for preventive and therapeutic intervention in each case. Thus, although survival of patients with alcoholic cirrhosis seems to be similar to that of patients with HCV-related cirrhosis (HCV-C), there are important differences in the altered cellular and molecular mechanisms implicated in the progression toward human liver cirrhosis. The predominant features of HCV-C are more related with those that allow viral evasion of the immune defenses, especially although not exclusively, inhibition of interferons secretion, natural killer cells activation and T cell-mediated cytotoxicity. On the contrary, the inflammatory status of alcohol-induced cirrhosis is determined by the combined effect of direct hepatotoxicity of ethanol metabolites and increases of the intestinal permeability, allowing bacteria and bacterial products translocation, into the portal circulation, mesenteric lymph nodes and peritoneal cavity. This phenomenon generates a stronger pro-inflammatory response compared with HCV-related cirrhosis. Hence, therapeutic intervention in HCV-related cirrhosis must be mainly focused to counteract HCV-immune system evasion, while in the case of alcohol-induced cirrhosis it must try to break the inflammatory loop established at the gut-mesenteric lymph nodes-peritoneal-systemic axis.
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32
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Wang X, Zhang H, Abel AM, Nelson E. Protein kinase R (PKR) plays a pro-viral role in porcine reproductive and respiratory syndrome virus (PRRSV) replication by modulating viral gene transcription. Arch Virol 2015; 161:327-33. [DOI: 10.1007/s00705-015-2671-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 10/31/2015] [Indexed: 01/01/2023]
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33
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Fortes P, Morris KV. Long noncoding RNAs in viral infections. Virus Res 2015; 212:1-11. [PMID: 26454188 DOI: 10.1016/j.virusres.2015.10.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 10/01/2015] [Indexed: 01/11/2023]
Abstract
Viral infections induce strong modifications in the cell transcriptome. Among the RNAs whose expression is altered by infection are long noncoding RNAs (lncRNAs). LncRNAs are transcripts with potential to function as RNA molecules. Infected cells may express viral lncRNAs, cellular lncRNAs and chimeric lncRNAs formed by viral and cellular sequences. Some viruses express viral lncRNAs whose function is essential for viral viability. They are transcribed by polymerase II or III and some of them can be processed by unique maturation steps performed by host cell machineries. Some viral lncRNAs control transcription, stability or translation of cellular and viral genes. Surprisingly, similar functions can be exerted by cellular lncRNAs induced by infection. Expression of cellular lncRNAs may be altered in response to viral replication or viral protein expression. However, many cellular lncRNAs respond to the antiviral pathways induced by infection. In fact, many lncRNAs function as positive or negative regulators of the innate antiviral response. Our current knowledge about the identity and function of lncRNAs in infected cells is very limited. However, research into this field has already helped in the identification of novel cellular pathways and may help in the development of therapeutic tools for the treatment of viral infections, autoimmune diseases, neurological disorders and cancer.
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Affiliation(s)
- Puri Fortes
- Center for Applied Medical Research (CIMA) and Navarra Institute for Health Research (IdiSNA), Department of Gene Therapy and Hepatology, University of Navarra, Pamplona, Spain.
| | - Kevin V Morris
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA; School of Biotechnology and Biomedical Sciences, University of New South Wales, Kensington, NSW, Australia
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34
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Abstract
Viral infections induce strong modifications in the cell transcriptome. Among the RNAs whose expression is altered by infection are long noncoding RNAs (lncRNAs). LncRNAs are transcripts with potential to function as RNA molecules. Infected cells may express viral lncRNAs, cellular lncRNAs and chimeric lncRNAs formed by viral and cellular sequences. Some viruses express viral lncRNAs whose function is essential for viral viability. They are transcribed by polymerase II or III and some of them can be processed by unique maturation steps performed by host cell machineries. Some viral lncRNAs control transcription, stability or translation of cellular and viral genes. Surprisingly, similar functions can be exerted by cellular lncRNAs induced by infection. Expression of cellular lncRNAs may be altered in response to viral replication or viral protein expression. However, many cellular lncRNAs respond to the antiviral pathways induced by infection. In fact, many lncRNAs function as positive or negative regulators of the innate antiviral response. Our current knowledge about the identity and function of lncRNAs in infected cells is very limited. However, research into this field has already helped in the identification of novel cellular pathways and may help in the development of therapeutic tools for the treatment of viral infections, autoimmune diseases, neurological disorders and cancer.
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Affiliation(s)
- Puri Fortes
- Center for Applied Medical Research (CIMA) and Navarra Institute for Health Research (IdiSNA), Department of Gene Therapy and Hepatology, University of Navarra, Pamplona, Spain.
| | - Kevin V Morris
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA; School of Biotechnology and Biomedical Sciences, University of New South Wales, Kensington, NSW, Australia
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35
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Carnero E, Fortes P. HCV infection, IFN response and the coding and non-coding host cell genome. Virus Res 2015; 212:85-102. [PMID: 26454190 DOI: 10.1016/j.virusres.2015.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 10/01/2015] [Indexed: 02/07/2023]
Abstract
HCV is an ideal model to study how the infected cell is altered to allow the establishment of a chronic infection. After infection, the transcriptome of the cell changes in response to the virus or to the antiviral pathways induced by infection. The cell has evolved to sense HCV soon after infection and to activate antiviral pathways. In turn, HCV has evolved to block the antiviral pathways induced by the cell and, at the same time, to use some for its own benefit. In this review, we summarize the proviral and antiviral factors induced in HCV infected cells. These factors can be proteins and microRNAs, but also long noncoding RNAs (lncRNAs) that are induced by infection. Interestingly, several of the lncRNAs upregulated after HCV infection have oncogenic functions, suggesting that upregulation of lncRNAs could explain, at least in part, the increased rate of liver tumors observed in HCV-infected patients. Other lncRNAs induced by HCV infection may regulate the expression of coding genes required for replication or control genes involved in the cellular antiviral response. Given the evolutionary pressure imposed by viral infections and that lncRNAs are specially targeted by evolution, we believe that the study of proviral and antiviral lncRNAs may lead to unexpected discoveries that may have a strong impact on basic science and translational research.
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Affiliation(s)
- Elena Carnero
- Center for Applied Medical Research (CIMA) and Navarra Institute for Health Research (IdiSNA), Department of Gene Therapy and Hepatology, University of Navarra, Pamplona, Spain
| | - Puri Fortes
- Center for Applied Medical Research (CIMA) and Navarra Institute for Health Research (IdiSNA), Department of Gene Therapy and Hepatology, University of Navarra, Pamplona, Spain.
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36
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Y-Box Binding Protein 1 Stabilizes Hepatitis C Virus NS5A via Phosphorylation-Mediated Interaction with NS5A To Regulate Viral Propagation. J Virol 2015; 89:11584-602. [PMID: 26355086 DOI: 10.1128/jvi.01513-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/01/2015] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED Replication of hepatitis C virus (HCV) is dependent on virus-encoded proteins and numerous cellular factors. DDX3 is a well-known host cofactor of HCV replication. In this study, we investigated the role of a DDX3-interacting protein, Y-box binding protein 1 (YB-1), in the HCV life cycle. Both YB-1 and DDX3 interacted with the viral nonstructural protein NS5A. During HCV infection, YB-1 partially colocalized with NS5A and the HCV replication intermediate double-stranded RNA (dsRNA) in HCV-infected Huh-7.5.1 cells. Despite sharing the same interacting partners, YB-1 participated in HCV RNA replication but was dispensable in steady-state HCV RNA replication, different from the action of DDX3. Moreover, knockdown of YB-1 in HCV-infected cells prevented infectious virus production and reduced the ratio of hyperphosphorylated (p58) to hypophosphorylated (p56) forms of NS5A, whereas DDX3 silencing did not affect the ratio of the p58 and p56 phosphoforms of NS5A. Interestingly, silencing of YB-1 severely reduced NS5A protein stability in NS5A-ectopically expressing, replicon-containing, and HCV-infected cells. Furthermore, mutations of serine 102 of YB-1 affected both YB-1-NS5A interaction and NS5A-stabilizing activity of YB-1, indicating that this Akt phosphorylation site of YB-1 plays an important role in stabilizing NS5A. Collectively, our results support a model in which the event of YB-1 phosphorylation-mediated interaction with NS5A results in stabilizing NS5A to sustain HCV RNA replication and infectious HCV production. Overall, our study may reveal a new aspect for the development of novel anti-HCV drugs. IMPORTANCE Chronic hepatitis C virus (HCV) infection induces liver cirrhosis and hepatocellular carcinoma. The viral nonstructural protein NS5A co-opting various cellular signaling pathways and cofactors to support viral genome replication and virion assembly is a new strategy for anti-HCV drug development. NS5A phosphorylation is believed to modulate switches between different stages of the HCV life cycle. In this study, we identified the cellular protein YB-1 as a novel NS5A-interacting protein. YB-1 is a multifunctional protein participating in oncogenesis and is an oncomarker of hepatocellular carcinoma (HCC). We found that YB-1 protects NS5A from degradation and likely regulates NS5A phosphorylation through its phosphorylation-dependent interaction with NS5A, which might be controlled by HCV-induced signaling pathways. Our observations suggest a model in which HCV modulates NS5A level and the ratio of the p58 and p56 phosphoforms for efficient viral propagation via regulation of cellular signaling inducing YB-1 phosphorylation. Our finding may provide new aspects for developing novel anti-HCV drugs.
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37
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Herrero-Ruiz J, Mora-Santos M, Giráldez S, Sáez C, Japón MA, Tortolero M, Romero F. βTrCP controls the lysosome-mediated degradation of CDK1, whose accumulation correlates with tumor malignancy. Oncotarget 2015; 5:7563-74. [PMID: 25149538 PMCID: PMC4202144 DOI: 10.18632/oncotarget.2274] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In mammals, cell cycle progression is controlled by cyclin-dependent kinases, among which CDK1 plays important roles in the regulation of the G2/M transition, G1 progression and G1/S transition. CDK1 is highly regulated by its association to cyclins, phosphorylation and dephosphorylation, changes in subcellular localization, and by direct binding of CDK inhibitor proteins. CDK1 steady-state protein levels are held constant throughout the cell cycle by a coordinated regulation of protein synthesis and degradation. We show that CDK1 is ubiquitinated by the E3 ubiquitin ligase SCFβTrCP and degraded by the lysosome. Furthermore, we found that DNA damage not only triggers the stabilization of inhibitory phosphorylation sites on CDK1 and repression of CDK1 gene expression, but also regulates βTrCP-induced CDK1 degradation in a cell type-dependent manner. Specifically, treatment with the chemotherapeutic agent doxorubicin in certain cell lines provokes CDK1 degradation and induces apoptosis, whereas in others it inhibits destruction of the protein. These observations raise the possibility that different tumor types, depending on their pathogenic spectrum mutations, may display different sensitivity to βTrCP-induced CDK1 degradation after DNA damage. Finally, we found that CDK1 accumulation in patients’ tumors shows a negative correlation with βTrCP and a positive correlation with the degree of tumor malignancy.
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Affiliation(s)
- Joaquín Herrero-Ruiz
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Mar Mora-Santos
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Servando Giráldez
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Carmen Sáez
- Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla and Departamento de Anatomía Patológica, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | - Miguel A Japón
- Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla and Departamento de Anatomía Patológica, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | - Maria Tortolero
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Francisco Romero
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
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TNF-α Induced by Hepatitis C Virus via TLR7 and TLR8 in Hepatocytes Supports Interferon Signaling via an Autocrine Mechanism. PLoS Pathog 2015; 11:e1004937. [PMID: 26023919 PMCID: PMC4449221 DOI: 10.1371/journal.ppat.1004937] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 05/06/2015] [Indexed: 02/07/2023] Open
Abstract
Invasion by infectious pathogens can elicit a range of cytokine responses from host cells. These cytokines provide the initial host defense mechanism. In this report, we demonstrate that TNF-α, a pro-inflammatory cytokine, can be induced by hepatitis C virus (HCV) in its host cells in a biphasic manner. The initial induction of TNF-α by HCV was prompt and could be blocked by the antibody directed against the HCV E2 envelope protein and by chemicals that inhibit endocytosis, indicating the specificity of endocytic uptake of HCV in this induction. Further studies indicated that the induction of TNF-α was dependent on toll-like receptors 7 and 8 (TLR7/8) but not on other intracellular pattern recognition receptors. Consistently, siRNA-mediated gene silencing of the downstream effectors in the TLR7/8 signaling pathway including MyD88, IRAK1, TRAF6, TAK1 and p65 NF-κB suppressed the expression of TNF-α. The role of p65 NF-κB in the induction of TNF-α via transcriptional up-regulation was further confirmed by the chromatin immunoprecipitation assay. TNF-α induced by HCV could activate its own receptor TNFR1 on hepatocytes to suppress HCV replication. This suppressive effect of TNF-α on HCV was due to its role in supporting interferon signaling, as the suppression of its expression led to the loss of IFNAR2 and impaired interferon signaling and the induction of interferon-stimulated genes. In conclusion, our results indicate that hepatocytes can sense HCV infection via TLR7/8 to induce the expression of TNF-α, which inhibits HCV replication via an autocrine mechanism to support interferon signaling. Hepatitis C virus (HCV) patients have increased levels of circulating tumor necrosis factor-α (TNF-α). In this report, we demonstrate that HCV can directly induce the expression of TNF-α in hepatocytes in a biphasic manner via NF-κB. The induction of TNF-α by HCV in the first phase is prompt, requires no HCV gene expression and is dependent on TLR7 and TLR8 and their downstream effectors. TNF-α induced by HCV supports interferon signaling via an autocrine mechanism and suppresses HCV replication, as abolishing the expression of TNF-α or its receptor TNFR1 results in the loss of IFNAR2, a subunit of the type I interferon receptor, and an increase of HCV replication. Our studies thus reveal an interesting interplay between HCV and hepatocytes, with the virus attempting to blunt the IFN response by depleting IFNAR2 and the host cell overcoming this blunting effect of HCV by using TNF-α to restore the expression of IFNAR2.
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Liu WJ, Yang YT, Zhao MQ, Dong XY, Gou HC, Pei JJ, Chen JD. PKR activation enhances replication of classical swine fever virus in PK-15 cells. Virus Res 2015; 204:47-57. [PMID: 25899421 PMCID: PMC7114430 DOI: 10.1016/j.virusres.2015.04.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 03/25/2015] [Accepted: 04/09/2015] [Indexed: 12/22/2022]
Abstract
CSFV infection triggers PKR and eIF2α protein phosphorylation. PKR overexpression stimulates viral replication. PKR depletion blocks eIF2α phosphorylation and suppresses viral replication. PKR depletion increases IFN-β, and enhances the antiviral effect of IFN.
Classical swine fever (CSF) is a highly contagious swine disease that is responsible for economic losses worldwide. Protein kinase R (PK)R is an important protein in the host viral response; however, the role of PKR in CSFV infection remains unknown. This issue was addressed in the present study using the PK-15 swine kidney cell line. We found that CSFV infection increased the phosphorylation of eukaryotic translation initiation factor (eIF)2α and its kinase PKR. However, the expression of viral proteins continued to increase. Furthermore, PKR overexpression enhanced CSFV replication, while PKR inhibition resulted in reduced CSFV replication and an increase in interferon (IFN) induction. In addition, PKR was responsible for eIF2α phosphorylation in CSFV-infected cells. These results suggest that the activation of PKR during CSFV infection is beneficial to the virus. The virus is able to commandeer the host cell's translation machinery for viral protein synthesis while evading innate immune defenses.
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Affiliation(s)
- Wen-Jun Liu
- College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China
| | - You-Tian Yang
- College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China
| | - Ming-Qiu Zhao
- College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China
| | - Xiao-Ying Dong
- College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China
| | - Hong-Chao Gou
- College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China
| | - Jing-Jing Pei
- College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China
| | - Jin-Ding Chen
- College of Veterinary Medicine, South China Agricultural University, 483 Wu Shan Road, Tian He District, Guangzhou 510642, China.
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Coccia EM, Battistini A. Early IFN type I response: Learning from microbial evasion strategies. Semin Immunol 2015; 27:85-101. [PMID: 25869307 PMCID: PMC7129383 DOI: 10.1016/j.smim.2015.03.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/10/2015] [Indexed: 12/12/2022]
Abstract
Type I interferon (IFN) comprises a class of cytokines first discovered more than 50 years ago and initially characterized for their ability to interfere with viral replication and restrict locally viral propagation. As such, their induction downstream of germ-line encoded pattern recognition receptors (PRRs) upon recognition of pathogen-associated molecular patterns (PAMPs) is a hallmark of the host antiviral response. The acknowledgment that several PAMPs, not just of viral origin, may induce IFN, pinpoints at these molecules as a first line of host defense against a number of invading pathogens. Acting in both autocrine and paracrine manner, IFN interferes with viral replication by inducing hundreds of different IFN-stimulated genes with both direct anti-pathogenic as well as immunomodulatory activities, therefore functioning as a bridge between innate and adaptive immunity. On the other hand an inverse interference to escape the IFN system is largely exploited by pathogens through a number of tactics and tricks aimed at evading, inhibiting or manipulating the IFN pathway, that result in progression of infection or establishment of chronic disease. In this review we discuss the interplay between the IFN system and some selected clinically important and challenging viruses and bacteria, highlighting the wide array of pathogen-triggered molecular mechanisms involved in evasion strategies.
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Affiliation(s)
- Eliana M Coccia
- Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy
| | - Angela Battistini
- Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy.
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Yang DR, Zhu HZ. Hepatitis C virus and antiviral innate immunity: Who wins at tug-of-war? World J Gastroenterol 2015; 21:3786-3800. [PMID: 25852264 PMCID: PMC4385526 DOI: 10.3748/wjg.v21.i13.3786] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 01/21/2015] [Accepted: 02/13/2015] [Indexed: 02/06/2023] Open
Abstract
Hepatitis C virus (HCV) is a major human pathogen of chronic hepatitis and related liver diseases. Innate immunity is the first line of defense against invading foreign pathogens, and its activation is dependent on the recognition of these pathogens by several key sensors. The interferon (IFN) system plays an essential role in the restriction of HCV infection via the induction of hundreds of IFN-stimulated genes (ISGs) that inhibit viral replication and spread. However, numerous factors that trigger immune dysregulation, including viral factors and host genetic factors, can help HCV to escape host immune response, facilitating viral persistence. In this review, we aim to summarize recent advances in understanding the innate immune response to HCV infection and the mechanisms of ISGs to suppress viral survival, as well as the immune evasion strategies for chronic HCV infection.
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Horner SM. Insights into antiviral innate immunity revealed by studying hepatitis C virus. Cytokine 2015; 74:190-7. [PMID: 25819428 DOI: 10.1016/j.cyto.2015.03.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 02/07/2023]
Abstract
Experimental studies on the interactions of the positive strand RNA virus hepatitis C virus (HCV) with the host have contributed to several discoveries in the field of antiviral innate immunity. These include revealing the antiviral sensing pathways that lead to the induction of type I interferon (IFN) during HCV infection and also the importance of type III IFNs in the antiviral immune response to HCV. These studies on HCV/host interactions have contributed to our overall understanding of viral sensing and viral evasion of the antiviral intracellular innate immune response. In this review, I will highlight how these studies of HCV/host interactions have led to new insights into antiviral innate immunity. Overall, I hope to emphasize that studying antiviral immunity in the context of virus infection is necessary to fully understand antiviral immunity and how it controls the outcome of viral infection.
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Affiliation(s)
- Stacy M Horner
- Department of Molecular Genetics & Microbiology, Duke University Medical Center, Durham, NC 27710, United States; Department of Medicine, Duke University Medical Center, Durham, NC 27710, United States.
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Barriocanal M, Carnero E, Segura V, Fortes P. Long Non-Coding RNA BST2/BISPR is Induced by IFN and Regulates the Expression of the Antiviral Factor Tetherin. Front Immunol 2015; 5:655. [PMID: 25620967 PMCID: PMC4288319 DOI: 10.3389/fimmu.2014.00655] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 12/08/2014] [Indexed: 12/17/2022] Open
Abstract
Many long non-coding RNAs (lncRNAs) are expressed in cells but only a few have been well characterized. In these cases, lncRNAs have been shown to be key regulators of several cellular processes. Therefore, there is a great need to understand the function of more lncRNAs and their regulation in response to stimuli. Interferon (IFN) is a key molecule in the cellular antiviral response. IFN binding to its receptor activates transcription of several IFN-stimulated genes (ISGs) that function as potent antivirals. In addition, several ISGs are positive or negative regulators of the IFN pathway. This is essential to ensure a strong antiviral response and a later return of the cell to homeostasis. As the ISGs described to date are coding genes, we sought to determine whether IFN also regulates the expression of long non-coding ISGs. To this aim, we used RNA sequencing to analyze the transcriptome of control and HuH7 cells treated with IFNα2. The results show that IFN-treatment regulates the expression of several unknown non-coding transcripts. We have validated two lncRNAs upregulated after treatment with different doses of type I IFNα2 in different cells or with type III IFNλ. These lncRNAs were also induced by influenza and vesicular stomatitis virus mutants unable to block the IFN response, but not by several wild-type lytic viruses tested. These lncRNA genes were named lncISG15 and lncBST2 as they are located close to ISGs ISG15 and BST2, respectively. Interestingly, inhibition experiments showed that lncBST2 is a positive regulator of BST2. Therefore lncBST2 has been renamed BISPR, from BST2 IFN-stimulated positive regulator. Our results may have therapeutic implications as lncBST2/BISPR, but also lncISG15 and their coding neighbors, are increased in cells infected with hepatitis C virus and in the liver of infected patients. These results allow us to hypothesize that several lncRNAs could be activated by IFN to control the potency of the antiviral IFN response.
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Affiliation(s)
- Marina Barriocanal
- Department of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), University of Navarra , Pamplona , Spain
| | - Elena Carnero
- Department of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), University of Navarra , Pamplona , Spain
| | - Victor Segura
- Bioinformatics Unit, Center for Applied Medical Research (CIMA), University of Navarra , Pamplona , Spain
| | - Puri Fortes
- Department of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), University of Navarra , Pamplona , Spain
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Emerging roles of interferon-stimulated genes in the innate immune response to hepatitis C virus infection. Cell Mol Immunol 2014; 13:11-35. [PMID: 25544499 PMCID: PMC4712384 DOI: 10.1038/cmi.2014.127] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 11/21/2014] [Accepted: 11/22/2014] [Indexed: 12/14/2022] Open
Abstract
Infection with hepatitis C virus (HCV), a major viral cause of chronic liver disease, frequently progresses to steatosis and cirrhosis, which can lead to hepatocellular carcinoma. HCV infection strongly induces host responses, such as the activation of the unfolded protein response, autophagy and the innate immune response. Upon HCV infection, the host induces the interferon (IFN)-mediated frontline defense to limit virus replication. Conversely, HCV employs diverse strategies to escape host innate immune surveillance. Type I IFN elicits its antiviral actions by inducing a wide array of IFN-stimulated genes (ISGs). Nevertheless, the mechanisms by which these ISGs participate in IFN-mediated anti-HCV actions remain largely unknown. In this review, we first outline the signaling pathways known to be involved in the production of type I IFN and ISGs and the tactics that HCV uses to subvert innate immunity. Then, we summarize the effector mechanisms of scaffold ISGs known to modulate IFN function in HCV replication. We also highlight the potential functions of emerging ISGs, which were identified from genome-wide siRNA screens, in HCV replication. Finally, we discuss the functions of several cellular determinants critical for regulating host immunity in HCV replication. This review will provide a basis for understanding the complexity and functionality of the pleiotropic IFN system in HCV infection. Elucidation of the specificity and the mode of action of these emerging ISGs will also help to identify novel cellular targets against which effective HCV therapeutics can be developed.
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45
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Emerging roles of interferon-stimulated genes in the innate immune response to hepatitis C virus infection. Cell Mol Immunol 2014; 11:218-20. [PMID: 25544499 DOI: 10.1038/cmi.2014.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 01/03/2014] [Accepted: 01/06/2014] [Indexed: 12/16/2022] Open
Abstract
Infection with hepatitis C virus (HCV), a major viral cause of chronic liver disease, frequently progresses to steatosis and cirrhosis, which can lead to hepatocellular carcinoma. HCV infection strongly induces host responses, such as the activation of the unfolded protein response, autophagy and the innate immune response. Upon HCV infection, the host induces the interferon (IFN)-mediated frontline defense to limit virus replication. Conversely, HCV employs diverse strategies to escape host innate immune surveillance. Type I IFN elicits its antiviral actions by inducing a wide array of IFN-stimulated genes (ISGs). Nevertheless, the mechanisms by which these ISGs participate in IFN-mediated anti-HCV actions remain largely unknown. In this review, we first outline the signaling pathways known to be involved in the production of type I IFN and ISGs and the tactics that HCV uses to subvert innate immunity. Then, we summarize the effector mechanisms of scaffold ISGs known to modulate IFN function in HCV replication. We also highlight the potential functions of emerging ISGs, which were identified from genome-wide siRNA screens, in HCV replication. Finally, we discuss the functions of several cellular determinants critical for regulating host immunity in HCV replication. This review will provide a basis for understanding the complexity and functionality of the pleiotropic IFN system in HCV infection. Elucidation of the specificity and the mode of action of these emerging ISGs will also help to identify novel cellular targets against which effective HCV therapeutics can be developed.
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46
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Gokhale NS, Vazquez C, Horner SM. Hepatitis C Virus. Strategies to Evade Antiviral Responses. Future Virol 2014; 9:1061-1075. [PMID: 25983854 DOI: 10.2217/fvl.14.89] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hepatitis C virus (HCV) causes chronic liver disease and poses a major clinical and economic burden worldwide. HCV is an RNA virus that is sensed as non-self in the infected liver by host pattern recognition receptors, triggering downstream signaling to interferons (IFNs). The type III IFNs play an important role in immunity to HCV, and human genetic variation in their gene loci is associated with differential HCV infection outcomes. HCV evades host antiviral innate immune responses to mediate a persistent infection in the liver. This review focuses on anti-HCV innate immune sensing, innate signaling and effectors, and the processes and proteins used by HCV to evade and regulate host innate immunity.
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Affiliation(s)
- Nandan S Gokhale
- Department of Molecular Genetics & Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Christine Vazquez
- Department of Molecular Genetics & Microbiology, Duke University Medical Center, Durham, NC 27710
| | - Stacy M Horner
- Department of Molecular Genetics & Microbiology, Duke University Medical Center, Durham, NC 27710 ; Department of Medicine, Duke University Medical Center, Durham, NC 27710
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47
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Increased replicative fitness can lead to decreased drug sensitivity of hepatitis C virus. J Virol 2014; 88:12098-111. [PMID: 25122776 DOI: 10.1128/jvi.01860-14] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Passage of hepatitis C virus (HCV) in human hepatoma cells resulted in populations that displayed partial resistance to alpha interferon (IFN-α), telaprevir, daclatasvir, cyclosporine, and ribavirin, despite no prior exposure to these drugs. Mutant spectrum analyses and kinetics of virus production in the absence and presence of drugs indicate that resistance is not due to the presence of drug resistance mutations in the mutant spectrum of the initial or passaged populations but to increased replicative fitness acquired during passage. Fitness increases did not alter host factors that lead to shutoff of general host cell protein synthesis and preferential translation of HCV RNA. The results imply that viral replicative fitness is a mechanism of multidrug resistance in HCV. Importance: Viral drug resistance is usually attributed to the presence of amino acid substitutions in the protein targeted by the drug. In the present study with HCV, we show that high viral replicative fitness can confer a general drug resistance phenotype to the virus. The results exclude the possibility that genomes with drug resistance mutations are responsible for the observed phenotype. The fact that replicative fitness can be a determinant of multidrug resistance may explain why the virus is less sensitive to drug treatments in prolonged chronic HCV infections that favor increases in replicative fitness.
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48
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Daito T, Watashi K, Sluder A, Ohashi H, Nakajima S, Borroto-Esoda K, Fujita T, Wakita T. Cyclophilin inhibitors reduce phosphorylation of RNA-dependent protein kinase to restore expression of IFN-stimulated genes in HCV-infected cells. Gastroenterology 2014; 147:463-72. [PMID: 24786893 DOI: 10.1053/j.gastro.2014.04.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 04/13/2014] [Accepted: 04/18/2014] [Indexed: 01/25/2023]
Abstract
BACKGROUND & AIMS Cyclophilin inhibitors are being developed for treatment of hepatitis C virus (HCV) infection. They are believed to inhibit the HCV replication complex. We investigated whether cyclophilin inhibitors interact with interferon (IFN) signaling in cultured cells infected with HCV. METHODS We used immunoblot assays to compare expression of IFN-stimulated genes (ISGs) and of components of IFN signaling in HCV-infected and uninfected cells. RESULTS Incubation with IFN alfa induced expression of ISGs in noninfected cells and, to a lesser extent, in HCV-infected cells; addition of the cyclophilin inhibitor SCY-635 restored expression of ISG products in HCV-infected cells. SCY-635 reduced phosphorylation of double-strand RNA-dependent protein kinase (PKR) and its downstream factor eIF2α; the phosphorylated forms of these proteins are negative regulators of ISG translation. Cyclophilin A interacted physically with PKR; this interaction was disrupted by SCY-635. SCY-635 also suppressed PKR-mediated formation of stress granules. Cyclophilin inhibitors were found to inhibit PKR phosphorylation and stress granule formation in HCV-infected and uninfected cells. CONCLUSIONS In cultured cells, cyclophilin inhibitors reverse the attenuation of the IFN response by HCV, in addition to their effects on HCV replication complex. Cyclophilin A regulation of PKR has been proposed as a mechanism for observed effects of cyclophilin inhibitors on IFN signaling. We found that cyclophilin inhibitors reduce phosphorylation of PKR and eIF2α during HCV infection to allow for translation of ISG products. Proteins in this pathway might be developed as targets for treatment of HCV infection.
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Affiliation(s)
- Takuji Daito
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan; SCYNEXIS, Inc, Durham, North Carolina
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.
| | | | - Hirofumi Ohashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Syo Nakajima
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | | | - Takashi Fujita
- Laboratory of Molecular Genetics, Institute for Virus Research, Kyoto University, Kyoto, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
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Burugu S, Daher A, Meurs EF, Gatignol A. HIV-1 translation and its regulation by cellular factors PKR and PACT. Virus Res 2014; 193:65-77. [PMID: 25064266 DOI: 10.1016/j.virusres.2014.07.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/13/2014] [Accepted: 07/14/2014] [Indexed: 12/24/2022]
Abstract
The synthesis of proteins from viral mRNA is the first step towards viral assembly. Viruses are dependent upon the cellular translation machinery to synthesize their own proteins. The synthesis of proteins from the human immunodeficiency virus (HIV) type 1 and 2 RNAs utilize several alternative mechanisms. The regulation of viral protein production requires a constant interplay between viral requirements and the cell response to viral infection. Among the antiviral cell responses, the interferon-induced RNA activated protein kinase, PKR, regulates the cellular and viral translation. During HIV-1 infection, PKR activation is highly regulated by viral and cellular factors. The cellular TAR RNA Binding Protein, TRBP, the Adenosine Deaminase acting on RNA, ADAR1, and the PKR Activator, PACT, play important roles. Recent data show that PACT changes its function from activator to inhibitor in HIV-1 infected cells. Therefore, HIV-1 has evolved to replicate in cells in which TRBP, ADAR1 and PACT prevent PKR activation to allow efficient viral protein synthesis. This proper translation will initiate the assembly of viral particles.
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Affiliation(s)
- Samantha Burugu
- Virus-cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, QC, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada
| | - Aïcha Daher
- Virus-cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, QC, Canada
| | - Eliane F Meurs
- Institut Pasteur, Department of Virology, Hepacivirus and Innate Immunity Unit, Paris, France
| | - Anne Gatignol
- Virus-cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, QC, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC, Canada; Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC, Canada.
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50
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Ashiru O, Howe JD, Butters TD. Nitazoxanide, an antiviral thiazolide, depletes ATP-sensitive intracellular Ca(2+) stores. Virology 2014; 462-463:135-48. [PMID: 24971706 DOI: 10.1016/j.virol.2014.05.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 04/01/2014] [Accepted: 05/14/2014] [Indexed: 12/31/2022]
Abstract
Nitazoxanide (NTZ) inhibits influenza, Japanese encephalitis, hepatitis B and hepatitis C virus replication but effects on the replication of other members of the Flaviviridae family has yet to be defined. The pestivirus bovine viral diarrhoea virus (BVDV) is a surrogate model for HCV infection and NTZ induced PKR and eIF2α phosphorylation in both uninfected and BVDV-infected cells. This led to the observation that NTZ depletes ATP-sensitive intracellular Ca(2+) stores. In addition to PKR and eIF2α phosphorylation, consequences of NTZ-mediated Ca(2+) mobilisation included induction of chronic sub-lethal ER stress as well as perturbation of viral protein N-linked glycosylation and trafficking. To adapt to NTZ-mediated ER stress, NTZ treated cells upregulated translation of Ca(2+)-binding proteins, including the ER chaperone Bip and the cytosolic pro-survival and anti-viral protein TCTP. Depletion of intracellular Ca(2+) stores is the primary consequence of NTZ treatment and is likely to underpin all antiviral mechanisms attributed to the thiazolide.
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Affiliation(s)
- Omodele Ashiru
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, Oxfordshire OX1 3QU, UK.
| | - Jonathon D Howe
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, Oxfordshire OX1 3QU, UK.
| | - Terry D Butters
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, Oxfordshire OX1 3QU, UK.
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