1
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Stancheva VG, Sanyal S. Positive-strand RNA virus replication organelles at a glance. J Cell Sci 2024; 137:jcs262164. [PMID: 39254430 PMCID: PMC11423815 DOI: 10.1242/jcs.262164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/11/2024] Open
Abstract
Membrane-bound replication organelles (ROs) are a unifying feature among diverse positive-strand RNA viruses. These compartments, formed as alterations of various host organelles, provide a protective niche for viral genome replication. Some ROs are characterised by a membrane-spanning pore formed by viral proteins. The RO membrane separates the interior from immune sensors in the cytoplasm. Recent advances in imaging techniques have revealed striking diversity in RO morphology and origin across virus families. Nevertheless, ROs share core features such as interactions with host proteins for their biogenesis and for lipid and energy transfer. The restructuring of host membranes for RO biogenesis and maintenance requires coordinated action of viral and host factors, including membrane-bending proteins, lipid-modifying enzymes and tethers for interorganellar contacts. In this Cell Science at a Glance article and the accompanying poster, we highlight ROs as a universal feature of positive-strand RNA viruses reliant on virus-host interplay, and we discuss ROs in the context of extensive research focusing on their potential as promising targets for antiviral therapies and their role as models for understanding fundamental principles of cell biology.
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Affiliation(s)
- Viktoriya G. Stancheva
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK
| | - Sumana Sanyal
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE, UK
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2
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Dai J, Feng Y, Liao Y, Tan L, Sun Y, Song C, Qiu X, Ding C. Virus infection and sphingolipid metabolism. Antiviral Res 2024; 228:105942. [PMID: 38908521 DOI: 10.1016/j.antiviral.2024.105942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/14/2024] [Accepted: 06/19/2024] [Indexed: 06/24/2024]
Abstract
Cellular sphingolipids have vital roles in human virus replication and spread as they are exploited by viruses for cell entry, membrane fusion, genome replication, assembly, budding, and propagation. Intracellular sphingolipid biosynthesis triggers conformational changes in viral receptors and facilitates endosomal escape. However, our current understanding of how sphingolipids precisely regulate viral replication is limited, and further research is required to comprehensively understand the relationships between viral replication and endogenous sphingolipid species. Emerging evidence now suggests that targeting and manipulating sphingolipid metabolism enzymes in host cells is a promising strategy to effectively combat viral infections. Additionally, serum sphingolipid species and concentrations could function as potential serum biomarkers to help monitor viral infection status in different patients. In this work, we comprehensively review the literature to clarify how viruses exploit host sphingolipid metabolism to accommodate viral replication and disrupt host innate immune responses. We also provide valuable insights on the development and use of antiviral drugs in this area.
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Affiliation(s)
- Jun Dai
- Experimental Animal Center, Zunyi Medical University, Zunyi, 563099, China
| | - Yiyi Feng
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Laboratory of Veterinary Microbiology and Animal Infectious Diseases, College of Animal Sciences and Veterinary Medicine, Guangxi University, Nanning, 530004, Guangxi China
| | - Ying Liao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Lei Tan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Yingjie Sun
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Cuiping Song
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Xusheng Qiu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China.
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, China.
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3
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Thomas S, Samuel SV, Hoch A, Syphurs C, Diray-Arce J. The Implication of Sphingolipids in Viral Infections. Int J Mol Sci 2023; 24:17303. [PMID: 38139132 PMCID: PMC10743733 DOI: 10.3390/ijms242417303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 12/03/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
Sphingolipids are involved in cell signaling and metabolic pathways, and their metabolites play a critical role in host defense against intracellular pathogens. Here, we review the known mechanisms of sphingolipids in viral infections and discuss the potential implication of the study of sphingolipid metabolism in vaccine and therapeutic development.
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Affiliation(s)
- Sanya Thomas
- Precision Vaccines Program, Department of Pediatrics, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (A.H.); (C.S.)
- Harvard Medical School, Boston, MA 02115, USA;
| | - Stephen Varghese Samuel
- Harvard Medical School, Boston, MA 02115, USA;
- Department of Emergency Medicine, Christian Medical College and Hospital, Vellore 632004, India
| | - Annmarie Hoch
- Precision Vaccines Program, Department of Pediatrics, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (A.H.); (C.S.)
| | - Caitlin Syphurs
- Precision Vaccines Program, Department of Pediatrics, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (A.H.); (C.S.)
| | - Joann Diray-Arce
- Precision Vaccines Program, Department of Pediatrics, Boston Children’s Hospital, Boston, MA 02115, USA; (S.T.); (A.H.); (C.S.)
- Harvard Medical School, Boston, MA 02115, USA;
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4
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Martin de Fourchambault E, Callens N, Saliou JM, Fourcot M, Delos O, Barois N, Thorel Q, Ramirez S, Bukh J, Cocquerel L, Bertrand-Michel J, Marot G, Sebti Y, Dubuisson J, Rouillé Y. Hepatitis C virus alters the morphology and function of peroxisomes. Front Microbiol 2023; 14:1254728. [PMID: 37808318 PMCID: PMC10551450 DOI: 10.3389/fmicb.2023.1254728] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 09/07/2023] [Indexed: 10/10/2023] Open
Abstract
Despite the introduction of effective treatments for hepatitis C in clinics, issues remain regarding the liver disease induced by chronic hepatitis C virus (HCV) infection. HCV is known to disturb the metabolism of infected cells, especially lipid metabolism and redox balance, but the mechanisms leading to HCV-induced pathogenesis are still poorly understood. In an APEX2-based proximity biotinylation screen, we identified ACBD5, a peroxisome membrane protein, as located in the vicinity of HCV replication complexes. Confocal microscopy confirmed the relocation of peroxisomes near HCV replication complexes and indicated that their morphology and number are altered in approximately 30% of infected Huh-7 cells. Peroxisomes are small versatile organelles involved among other functions in lipid metabolism and ROS regulation. To determine their importance in the HCV life cycle, we generated Huh-7 cells devoid of peroxisomes by inactivating the PEX5 and PEX3 genes using CRISPR/Cas9 and found that the absence of peroxisomes had no impact on replication kinetics or infectious titers of HCV strains JFH1 and DBN3a. The impact of HCV on peroxisomal functions was assessed using sub-genomic replicons. An increase of ROS was measured in peroxisomes of replicon-containing cells, correlated with a significant decrease of catalase activity with the DBN3a strain. In contrast, HCV replication had little to no impact on cytoplasmic and mitochondrial ROS, suggesting that the redox balance of peroxisomes is specifically impaired in cells replicating HCV. Our study provides evidence that peroxisome function and morphology are altered in HCV-infected cells.
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Affiliation(s)
- Esther Martin de Fourchambault
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U 1019 – UMR9017 – CIIL – Center for Infection and Immunity of Lille, Lille, France
| | - Nathalie Callens
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U 1019 – UMR9017 – CIIL – Center for Infection and Immunity of Lille, Lille, France
| | - Jean-Michel Saliou
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, UAR CNRS 2014 - US Inserm 41 - PLBS, Lille, France
| | - Marie Fourcot
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, UAR CNRS 2014 - US Inserm 41 - PLBS, Lille, France
| | - Oceane Delos
- MetaToul-MetaboHUB, National Infrastructure of Metabolomics and Fluxomics, Toulouse, France
- I2MC, Université de Toulouse, Inserm, Université Toulouse III – Paul Sabatier (UPS), Toulouse, France
| | - Nicolas Barois
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U 1019 – UMR9017 – CIIL – Center for Infection and Immunity of Lille, Lille, France
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, UAR CNRS 2014 - US Inserm 41 - PLBS, Lille, France
| | - Quentin Thorel
- Université de Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1011 - EGID, Lille, France
| | - Santseharay Ramirez
- Faculty of Health and Medical Sciences, Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital Hvidovre and Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Jens Bukh
- Faculty of Health and Medical Sciences, Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Copenhagen University Hospital Hvidovre and Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Laurence Cocquerel
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U 1019 – UMR9017 – CIIL – Center for Infection and Immunity of Lille, Lille, France
| | - Justine Bertrand-Michel
- MetaToul-MetaboHUB, National Infrastructure of Metabolomics and Fluxomics, Toulouse, France
- I2MC, Université de Toulouse, Inserm, Université Toulouse III – Paul Sabatier (UPS), Toulouse, France
| | - Guillemette Marot
- Université de Lille, Inria, CHU Lille, ULR 2694 - METRICS: Évaluation des technologies de santé et des pratiques médicales, Lille, France
| | - Yasmine Sebti
- Université de Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1011 - EGID, Lille, France
| | - Jean Dubuisson
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U 1019 – UMR9017 – CIIL – Center for Infection and Immunity of Lille, Lille, France
| | - Yves Rouillé
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U 1019 – UMR9017 – CIIL – Center for Infection and Immunity of Lille, Lille, France
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5
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McPhail JA, Burke JE. Molecular mechanisms of PI4K regulation and their involvement in viral replication. Traffic 2023; 24:131-145. [PMID: 35579216 DOI: 10.1111/tra.12841] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/07/2022] [Accepted: 03/30/2022] [Indexed: 11/28/2022]
Abstract
Lipid phosphoinositides are master signaling molecules in eukaryotic cells and key markers of organelle identity. Because of these important roles, the kinases and phosphatases that generate phosphoinositides must be tightly regulated. Viruses can manipulate this regulation, with the Type III phosphatidylinositol 4-kinases (PI4KA and PI4KB) being hijacked by many RNA viruses to mediate their intracellular replication through the formation of phosphatidylinositol 4-phosphate (PI4P)-enriched replication organelles (ROs). Different viruses have evolved unique approaches toward activating PI4K enzymes to form ROs, through both direct binding of PI4Ks and modulation of PI4K accessory proteins. This review will focus on PI4KA and PI4KB and discuss their roles in signaling, functions in membrane trafficking and manipulation by viruses. Our focus will be the molecular basis for how PI4KA and PI4KB are activated by both protein-binding partners and post-translational modifications, with an emphasis on understanding the different molecular mechanisms viruses have evolved to usurp PI4Ks. We will also discuss the chemical tools available to study the role of PI4Ks in viral infection.
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Affiliation(s)
- Jacob A McPhail
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada.,Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia, Canada
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6
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Röhrig AM, Jakobi K, Dietz J, Thomas D, Herrmann E, Welsch C, Sarrazin C, Pfeilschifter J, Zeuzem S, Grammatikos G. The role of serum sphingolipids as potential biomarkers of non-response to direct acting antiviral therapy in chronic hepatitis C virus infection. J Viral Hepat 2023; 30:138-147. [PMID: 36463431 DOI: 10.1111/jvh.13776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/07/2022] [Accepted: 11/14/2022] [Indexed: 12/09/2022]
Abstract
Elimination strategies of chronic hepatitis C virus (HCV) infection aim to optimize the high antiviral potency of direct-acting antivirals (DAAs). Sphingolipids (SLs) constitute bioactive lipid compounds with a remarkable second messenger potential. SL levels associate with responsiveness to interferon treatment in HCV-patients, thus prompting the question whether failure to DAAs can be predicted by the serologic sphingolipidomic profile. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to retrospectively quantify various sphingolipid metabolites in baseline serum samples of 97 chronic HCV patients with DAA failure compared with an age-matched cohort of 95 HCV-patients with sustained virological response (SVR). Sphingosine, sphinganine, sphingosine-1-phosphate (S1P) and sphinganine-1-phosphate (SA1P) serum concentrations were significantly upregulated at baseline in patients with DAA failure compared to patients with SVR. Similarly, GluC24:1Cer baseline levels were significantly upregulated in patients with DAA failure compared to the patients with SVR. However, GluC18Cer serum levels showed decreased baseline levels for patients with DAA failure compared to patients with SVR. In multivariate analysis sphinganine (OR 0.08494, CI 0.07393-0.9759, p = .021223), SA1P (OR 0.9818, CI 0.9653-0.9987, p = .034801), GluCerC18 (OR 1.0683, CI 1.0297-1.1104, p = .000786) and GluCer24:1 (OR 0.9961, CI 0.994-0.998, p = .000294) constituted independent predictors of treatment response. In conclusion, serum sphingolipid concentrations, in particular sphingosine, sphinganine and their derivatives S1P and SA1P as well as glucosylceramides may identify at baseline the minority of HCV patients with DAA failure. Serum sphingolipids could constitute additional biomarkers for national treatment strategies aiming to eliminate HCV infection.
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Affiliation(s)
- Aissa Miriam Röhrig
- Department of Internal Medicine 1, Goethe University Hospital, Frankfurt am Main, Germany
| | - Katja Jakobi
- Goethe University Hospital, Pharmazentrum Frankfurt/ZAFES, Frankfurt am Main, Germany
| | - Julia Dietz
- Department of Internal Medicine 1, Goethe University Hospital, Frankfurt am Main, Germany
| | - Dominique Thomas
- Goethe University, Institute of Clinical Pharmacology, Frankfurt am Main, Germany
| | - Eva Herrmann
- Department of Medicine, Goethe University, Institute of Biostatistics and Mathematical Modelling, Frankfurt am Main, Germany
| | - Christoph Welsch
- Department of Internal Medicine 1, Goethe University Hospital, Frankfurt am Main, Germany
| | - Christoph Sarrazin
- Department of Internal Medicine 1, Goethe University Hospital, Frankfurt am Main, Germany.,St. Josefs-Hospital, Wiesbaden, Germany
| | - Josef Pfeilschifter
- Goethe University Hospital, Pharmazentrum Frankfurt/ZAFES, Frankfurt am Main, Germany
| | - Stefan Zeuzem
- Department of Internal Medicine 1, Goethe University Hospital, Frankfurt am Main, Germany
| | - Georgios Grammatikos
- Department of Internal Medicine 1, Goethe University Hospital, Frankfurt am Main, Germany.,St' Lukes Hospital, Thessaloniki, Greece
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7
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Trivedi VS, Magnusen AF, Rani R, Marsili L, Slavotinek AM, Prows DR, Hopkin RJ, McKay MA, Pandey MK. Targeting the Complement-Sphingolipid System in COVID-19 and Gaucher Diseases: Evidence for a New Treatment Strategy. Int J Mol Sci 2022; 23:14340. [PMID: 36430817 PMCID: PMC9695449 DOI: 10.3390/ijms232214340] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/08/2022] [Accepted: 11/10/2022] [Indexed: 11/22/2022] Open
Abstract
Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2)-induced disease (COVID-19) and Gaucher disease (GD) exhibit upregulation of complement 5a (C5a) and its C5aR1 receptor, and excess synthesis of glycosphingolipids that lead to increased infiltration and activation of innate and adaptive immune cells, resulting in massive generation of pro-inflammatory cytokines, chemokines and growth factors. This C5a-C5aR1-glycosphingolipid pathway- induced pro-inflammatory environment causes the tissue damage in COVID-19 and GD. Strikingly, pharmaceutically targeting the C5a-C5aR1 axis or the glycosphingolipid synthesis pathway led to a reduction in glycosphingolipid synthesis and innate and adaptive immune inflammation, and protection from the tissue destruction in both COVID-19 and GD. These results reveal a common involvement of the complement and glycosphingolipid systems driving immune inflammation and tissue damage in COVID-19 and GD, respectively. It is therefore expected that combined targeting of the complement and sphingolipid pathways could ameliorate the tissue destruction, organ failure, and death in patients at high-risk of developing severe cases of COVID-19.
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Affiliation(s)
- Vyoma Snehal Trivedi
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
| | - Albert Frank Magnusen
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
| | - Reena Rani
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
| | - Luca Marsili
- Department of Neurology, James J. and Joan A. Gardner Center for Parkinson’s Disease and Movement Disorders, University of Cincinnati, 3113 Bellevue Ave, Cincinnati, OH 45219, USA
| | - Anne Michele Slavotinek
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
- Department of Pediatrics, College of Medicine, University of Cincinnati, 3230 Eden Ave, Cincinnati, OH 45267, USA
| | - Daniel Ray Prows
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
- Department of Pediatrics, College of Medicine, University of Cincinnati, 3230 Eden Ave, Cincinnati, OH 45267, USA
| | - Robert James Hopkin
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
- Department of Pediatrics, College of Medicine, University of Cincinnati, 3230 Eden Ave, Cincinnati, OH 45267, USA
| | - Mary Ashley McKay
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
| | - Manoj Kumar Pandey
- Cincinnati Children’s Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, Building R1, MLC 7016, Cincinnati, OH 45229, USA
- Department of Pediatrics, College of Medicine, University of Cincinnati, 3230 Eden Ave, Cincinnati, OH 45267, USA
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8
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de la Peña AT, Sliepen K, Eshun-Wilson L, Newby ML, Allen JD, Zon I, Koekkoek S, Chumbe A, Crispin M, Schinkel J, Lander GC, Sanders RW, Ward AB. Structure of the hepatitis C virus E1E2 glycoprotein complex. Science 2022; 378:263-269. [PMID: 36264808 PMCID: PMC10512783 DOI: 10.1126/science.abn9884] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Hepatitis C virus (HCV) infection is a leading cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma in humans and afflicts more than 58 million people worldwide. The HCV envelope E1 and E2 glycoproteins are essential for viral entry and comprise the primary antigenic target for neutralizing antibody responses. The molecular mechanisms of E1E2 assembly, as well as how the E1E2 heterodimer binds broadly neutralizing antibodies, remain elusive. Here, we present the cryo-electron microscopy structure of the membrane-extracted full-length E1E2 heterodimer in complex with three broadly neutralizing antibodies-AR4A, AT1209, and IGH505-at ~3.5-angstrom resolution. We resolve the interface between the E1 and E2 ectodomains and deliver a blueprint for the rational design of vaccine immunogens and antiviral drugs.
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Affiliation(s)
- Alba Torrents de la Peña
- Department of Integrative Structural Biology and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Kwinten Sliepen
- Department of Medical Microbiology and Infection Prevention, Laboratory of Experimental Virology, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious Diseases, 1105 AZ Amsterdam, Netherlands
| | - Lisa Eshun-Wilson
- Department of Integrative Structural Biology and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Maddy L. Newby
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Joel D. Allen
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Ian Zon
- Department of Medical Microbiology and Infection Prevention, Laboratory of Experimental Virology, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious Diseases, 1105 AZ Amsterdam, Netherlands
| | - Sylvie Koekkoek
- Department of Medical Microbiology and Infection Prevention, Laboratory of Experimental Virology, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious Diseases, 1105 AZ Amsterdam, Netherlands
| | - Ana Chumbe
- Department of Medical Microbiology and Infection Prevention, Laboratory of Experimental Virology, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious Diseases, 1105 AZ Amsterdam, Netherlands
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Janke Schinkel
- Department of Medical Microbiology and Infection Prevention, Laboratory of Experimental Virology, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious Diseases, 1105 AZ Amsterdam, Netherlands
| | - Gabriel C. Lander
- Department of Integrative Structural Biology and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Rogier W. Sanders
- Department of Medical Microbiology and Infection Prevention, Laboratory of Experimental Virology, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, Netherlands
- Amsterdam Institute for Infection and Immunity, Infectious Diseases, 1105 AZ Amsterdam, Netherlands
- Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Andrew B. Ward
- Department of Integrative Structural Biology and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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9
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Neufeldt CJ, Cortese M. Membrane architects: how positive-strand RNA viruses restructure the cell. J Gen Virol 2022; 103. [PMID: 35976091 DOI: 10.1099/jgv.0.001773] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Virus infection is a process that requires combined contributions from both virus and host factors. For this process to be efficient within the crowded host environment, viruses have evolved ways to manipulate and reorganize host structures to produce cellular microenvironments. Positive-strand RNA virus replication and assembly occurs in association with cytoplasmic membranes, causing a reorganization of these membranes to create microenvironments that support viral processes. Similarities between virus-induced membrane domains and cellular organelles have led to the description of these structures as virus replication organelles (vRO). Electron microscopy analysis of vROs in positive-strand RNA virus infected cells has revealed surprising morphological similarities between genetically diverse virus species. For all positive-strand RNA viruses, vROs can be categorized into two groups: those that make invaginations into the cellular membranes (In-vRO), and those that cause the production of protrusions from cellular membranes (Pr-vRO), most often in the form of double membrane vesicles (DMVs). In this review, we will discuss the current knowledge on the structure and biogenesis of these two different vRO classes as well as comparing morphology and function of vROs between various positive-strand RNA viruses. Finally, we will discuss recent studies describing pharmaceutical intervention in vRO formation as an avenue to control virus infection.
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Affiliation(s)
- Christopher John Neufeldt
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Mirko Cortese
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
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10
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Modulation of Zika virus replication via glycosphingolipids. Virology 2022; 572:17-27. [DOI: 10.1016/j.virol.2022.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/30/2022] [Accepted: 03/30/2022] [Indexed: 11/18/2022]
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11
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Lu Y, He P, Zhang Y, Ren Y, Zhang L. The emerging roles of retromer and sorting nexins in the life cycle of viruses. Virol Sin 2022; 37:321-330. [PMID: 35513271 PMCID: PMC9057928 DOI: 10.1016/j.virs.2022.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 04/12/2022] [Indexed: 02/06/2023] Open
Abstract
Retromer and sorting nexins (SNXs) transport cargoes from endosomes to the trans-Golgi network or plasma membrane. Recent studies have unveiled the emerging roles for retromer and SNXs in the life cycle of viruses, including members of Coronaviridae, Flaviviridae and Retroviridae. Key components of retromer/SNXs, such as Vps35, Vps26, SNX5 and SNX27, can affect multiple steps of the viral life cycle, including facilitating the entry of viruses into cells, participating in viral replication, and promoting the assembly of virions. Here we present a comprehensive updated review on the interplay between retromer/SNXs and virus, which will shed mechanistic insights into controlling virus infection. Retromer/SNXs could regulate viral infection directly or indirectly. Retromer/SNXs plays an important role for SARS-CoV-2 infection. HPV entry is mediated by retromer/SNXs. Retromer is required for HCV replication. Retromer affects the late step of HIV replication.
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12
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Bulankina AV, Richter RM, Welsch C. Regulatory Role of Phospholipids in Hepatitis C Virus Replication and Protein Function. Pathogens 2022; 11:102. [PMID: 35056049 PMCID: PMC8779051 DOI: 10.3390/pathogens11010102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/12/2022] [Accepted: 01/13/2022] [Indexed: 11/16/2022] Open
Abstract
Positive-strand RNA viruses such as hepatitis C virus (HCV) hijack key factors of lipid metabolism of infected cells and extensively modify intracellular membranes to support the viral lifecycle. While lipid metabolism plays key roles in viral particle assembly and maturation, viral RNA synthesis is closely linked to the remodeling of intracellular membranes. The formation of viral replication factories requires a number of interactions between virus proteins and host factors including lipids. The structure-function relationship of those proteins is influenced by their lipid environments and lipids that selectively modulate protein function. Here, we review our current understanding on the roles of phospholipids in HCV replication and of lipid-protein interactions in the structure-function relationship of the NS5A protein. NS5A is a key factor in membrane remodeling in HCV-infected cells and is known to recruit phosphatidylinositol 4-kinase III alpha to generate phosphatidylinositol 4-phosphate at the sites of replication. The dynamic interplay between lipids and viral proteins within intracellular membranes is likely key towards understanding basic mechanisms in the pathobiology of virus diseases, the mode of action of specific antiviral agents and related drug resistance mechanisms.
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Affiliation(s)
- Anna V. Bulankina
- Department of Internal Medicine 1, Goethe University Hospital Frankfurt, 60590 Frankfurt, Germany; (A.V.B.); (R.M.R.)
- Research Group “Molecular Evolution & Adaptation”, 60590 Frankfurt, Germany
| | - Rebecca M. Richter
- Department of Internal Medicine 1, Goethe University Hospital Frankfurt, 60590 Frankfurt, Germany; (A.V.B.); (R.M.R.)
- Research Group “Molecular Evolution & Adaptation”, 60590 Frankfurt, Germany
| | - Christoph Welsch
- Department of Internal Medicine 1, Goethe University Hospital Frankfurt, 60590 Frankfurt, Germany; (A.V.B.); (R.M.R.)
- Research Group “Molecular Evolution & Adaptation”, 60590 Frankfurt, Germany
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13
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Gao YG, McDonald J, Malinina L, Patel DJ, Brown RE. Ceramide-1-phosphate transfer protein promotes sphingolipid reorientation needed for binding during membrane interaction. J Lipid Res 2022; 63:100151. [PMID: 34808193 PMCID: PMC8953657 DOI: 10.1016/j.jlr.2021.100151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 12/16/2022] Open
Abstract
Lipid transfer proteins acquire and release their lipid cargoes by interacting transiently with source and destination biomembranes. In the GlycoLipid Transfer Protein (GLTP) superfamily, the two-layer all-α-helical GLTP-fold defines proteins that specifically target sphingolipids (SLs) containing either sugar or phosphate headgroups via their conserved but evolutionarily-modified SL recognitions centers. Despite comprehensive structural insights provided by X-ray crystallography, the conformational dynamics associated with membrane interaction and SL uptake/release by GLTP superfamily members have remained unknown. Herein, we report insights gained from molecular dynamics (MD) simulations into the conformational dynamics that enable ceramide-1-phosphate transfer proteins (CPTPs) to acquire and deliver ceramide-1-phosphate (C1P) during interaction with 1-palmitoyl-2-oleoyl phosphatidylcholine bilayers. The focus on CPTP reflects this protein's involvement in regulating pro-inflammatory eicosanoid production and autophagy-dependent inflammasome assembly that drives interleukin (IL-1β and IL-18) production and release by surveillance cells. We found that membrane penetration by CPTP involved α-6 helix and the α-2 helix N-terminal region, was confined to one bilayer leaflet, and was relatively shallow. Large-scale dynamic conformational changes were minimal for CPTP during membrane interaction or C1P uptake except for the α-3/α-4 helices connecting loop, which is located near the membrane interface and interacts with certain phosphoinositide headgroups. Apart from functioning as a shallow membrane-docking element, α-6 helix was found to adeptly reorient membrane lipids to help guide C1P hydrocarbon chain insertion into the interior hydrophobic pocket of the SL binding site.These findings support a proposed 'hydrocarbon chain-first' mechanism for C1P uptake, in contrast to the 'lipid polar headgroup-first' uptake used by most lipid-transfer proteins.
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Affiliation(s)
- Yong-Guang Gao
- Hormel Institute, University of Minnesota, Austin, MN, USA.
| | | | - Lucy Malinina
- Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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14
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Cuesta-Geijo MÁ, García-Dorival I, del Puerto A, Urquiza J, Galindo I, Barrado-Gil L, Lasala F, Cayuela A, Sorzano COS, Gil C, Delgado R, Alonso C. New insights into the role of endosomal proteins for African swine fever virus infection. PLoS Pathog 2022; 18:e1009784. [PMID: 35081156 PMCID: PMC8820605 DOI: 10.1371/journal.ppat.1009784] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 02/07/2022] [Accepted: 01/11/2022] [Indexed: 01/01/2023] Open
Abstract
African swine fever virus (ASFV) infectious cycle starts with the viral adsorption and entry into the host cell. Then, the virus is internalized via clathrin/dynamin mediated endocytosis and macropinocytosis. Similar to other viruses, ASF virion is then internalized and incorporated into the endocytic pathway. While the endosomal maturation entails luminal acidification, the decrease in pH acts on the multilayer structure of the virion dissolving the outer capsid. Upon decapsidation, the inner viral membrane is exposed to interact with the limiting membrane of the late endosome for fusion. Viral fusion is then necessary for the egress of incoming virions from endosomes into the cytoplasm, however this remains an intriguing and yet essential process for infection, specifically for the egress of viral nucleic acid into the cytoplasm for replication. ASFV proteins E248R and E199L, located at the exposed inner viral membrane, might be implicated in the fusion step. An interaction between these viral proteins and cellular endosomal proteins such as the Niemann-Pick C type 1 (NPC1) and lysosomal membrane proteins (Lamp-1 and -2) was shown. Furthermore, the silencing of these proteins impaired ASFV infection. It was also observed that NPC1 knock-out cells using CRISPR jeopardized ASFV infection and that the progression and endosomal exit of viral cores was arrested within endosomes at viral entry. These results suggest that the interactions of ASFV proteins with some endosomal proteins might be important for the membrane fusion step. In addition to this, reductions on ASFV infectivity and replication in NPC1 KO cells were accompanied by fewer and smaller viral factories. Our findings pave the way to understanding the role of proteins of the endosomal membrane in ASFV infection. African swine fever virus (ASFV) causes a deadly disease of pigs and wild boars that was endemic in Africa but has spread in recent years to Europe, Asia and Oceania with a high socioeconomic impact. ASFV enters the cell by endocytosis and has adapted to the endosomal conditions to acquire infectivity. Fusion of the internal viral membrane with the endosomal membrane is required for the exit of viral DNA into the cytoplasm to start replication. We have found that ASF virion internal membrane proteins E248R and E199L interact with the endosomal proteins Niemann Pick C1 (NPC1) and lysosomal membrane proteins (Lamp)-1 and -2. And, appear to be required for endosomal trafficking of ASF virions endosomal traffic and exit to the cytoplasm in the cell entry process. These molecules act regulating cholesterol flux from the endosome to the endoplasmic reticulum, and appear to be important for the viral infection cycle. In silenced and knockout cells, ASFV infection was affected at early and later stages. In null cells, virion entry and progression through the endosomal pathway at entry was arrested and several viral cores were retained at late endosomes without entering the fusion phase for cytoplasmic exit. These results provide new insights into the role of endosomal proteins for ASFV infection.
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Affiliation(s)
- Miguel Ángel Cuesta-Geijo
- Departmento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Isabel García-Dorival
- Departmento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Ana del Puerto
- Departmento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Jesús Urquiza
- Departmento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Inmaculada Galindo
- Departmento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Lucía Barrado-Gil
- Departmento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Fátima Lasala
- Instituto de Investigación Hospital 12 de Octubre Imas12, Madrid, Spain
| | - Ana Cayuela
- Centro Nacional de Biotecnología CSIC, Madrid, Spain
| | | | - Carmen Gil
- Centro de Investigaciones Biológicas Margarita Salas CSIC, Madrid, Spain
| | - Rafael Delgado
- Instituto de Investigación Hospital 12 de Octubre Imas12, Madrid, Spain
- Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Covadonga Alonso
- Departmento de Biotecnología, INIA-CSIC, Centro Nacional Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
- * E-mail:
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15
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Tabata K, Prasad V, Paul D, Lee JY, Pham MT, Twu WI, Neufeldt CJ, Cortese M, Cerikan B, Stahl Y, Joecks S, Tran CS, Lüchtenborg C, V'kovski P, Hörmann K, Müller AC, Zitzmann C, Haselmann U, Beneke J, Kaderali L, Erfle H, Thiel V, Lohmann V, Superti-Furga G, Brügger B, Bartenschlager R. Convergent use of phosphatidic acid for hepatitis C virus and SARS-CoV-2 replication organelle formation. Nat Commun 2021; 12:7276. [PMID: 34907161 PMCID: PMC8671429 DOI: 10.1038/s41467-021-27511-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 11/22/2021] [Indexed: 11/09/2022] Open
Abstract
Double membrane vesicles (DMVs) serve as replication organelles of plus-strand RNA viruses such as hepatitis C virus (HCV) and SARS-CoV-2. Viral DMVs are morphologically analogous to DMVs formed during autophagy, but lipids driving their biogenesis are largely unknown. Here we show that production of the lipid phosphatidic acid (PA) by acylglycerolphosphate acyltransferase (AGPAT) 1 and 2 in the ER is important for DMV biogenesis in viral replication and autophagy. Using DMVs in HCV-replicating cells as model, we found that AGPATs are recruited to and critically contribute to HCV and SARS-CoV-2 replication and proper DMV formation. An intracellular PA sensor accumulated at viral DMV formation sites, consistent with elevated levels of PA in fractions of purified DMVs analyzed by lipidomics. Apart from AGPATs, PA is generated by alternative pathways and their pharmacological inhibition also impaired HCV and SARS-CoV-2 replication as well as formation of autophagosome-like DMVs. These data identify PA as host cell lipid involved in proper replication organelle formation by HCV and SARS-CoV-2, two phylogenetically disparate viruses causing very different diseases, i.e. chronic liver disease and COVID-19, respectively. Host-targeting therapy aiming at PA synthesis pathways might be suitable to attenuate replication of these viruses.
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Affiliation(s)
- Keisuke Tabata
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
- Department of Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
- Laboratory of Intracellular Membrane Dynamics, Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Vibhu Prasad
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - David Paul
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Ji-Young Lee
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Minh-Tu Pham
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Woan-Ing Twu
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Christopher J Neufeldt
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Mirko Cortese
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Berati Cerikan
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Yannick Stahl
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Sebastian Joecks
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
- LI-COR Biosciences GmbH, Siemensstrasse 25A, Bad Homburg, Germany
| | - Cong Si Tran
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | | | - Philip V'kovski
- Institute of Virology and Immunology IVI, Bern, Switzerland
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Katrin Hörmann
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - André C Müller
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Carolin Zitzmann
- Institute of Bioinformatics and Center for Functional Genomics of Microbes, University Medicine Greifswald, Greifswald, Germany
- Los Alamos National Laboratory, Theoretical Biology and Biophysics, Los Alamos, NM, USA
| | - Uta Haselmann
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Jürgen Beneke
- BioQuant, Heidelberg University, Heidelberg, Germany
| | - Lars Kaderali
- Institute of Bioinformatics and Center for Functional Genomics of Microbes, University Medicine Greifswald, Greifswald, Germany
| | - Holger Erfle
- BioQuant, Heidelberg University, Heidelberg, Germany
| | - Volker Thiel
- Institute of Virology and Immunology IVI, Bern, Switzerland
- Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Volker Lohmann
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Giulio Superti-Furga
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Britta Brügger
- Biochemistry Center Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany.
- Division Virus-Associated Carcinogenesis, German Cancer Research Center, Heidelberg, Germany.
- German Center for Infection Research, Heidelberg Partner Site, Heidelberg, Germany.
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16
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Avota E, Bodem J, Chithelen J, Mandasari P, Beyersdorf N, Schneider-Schaulies J. The Manifold Roles of Sphingolipids in Viral Infections. Front Physiol 2021; 12:715527. [PMID: 34658908 PMCID: PMC8511394 DOI: 10.3389/fphys.2021.715527] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 09/06/2021] [Indexed: 12/13/2022] Open
Abstract
Sphingolipids are essential components of eukaryotic cells. In this review, we want to exemplarily illustrate what is known about the interactions of sphingolipids with various viruses at different steps of their replication cycles. This includes structural interactions during entry at the plasma membrane or endosomal membranes, early interactions leading to sphingolipid-mediated signal transduction, interactions with internal membranes and lipids during replication, and interactions during virus assembly and budding. Targeted interventions in sphingolipid metabolism - as far as they can be tolerated by cells and organisms - may open novel possibilities to support antiviral therapies. Human immunodeficiency virus type 1 (HIV-1) infections have intensively been studied, but for other viral infections, such as influenza A virus (IAV), measles virus (MV), hepatitis C virus (HCV), dengue virus, Ebola virus, and severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), investigations are still in their beginnings. As many inhibitors of sphingolipid metabolism are already in clinical use against other diseases, repurposing studies for applications in some viral infections appear to be a promising approach.
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Affiliation(s)
- Elita Avota
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Jochen Bodem
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Janice Chithelen
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Putri Mandasari
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Niklas Beyersdorf
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
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17
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Schneider-Schaulies S, Schumacher F, Wigger D, Schöl M, Waghmare T, Schlegel J, Seibel J, Kleuser B. Sphingolipids: Effectors and Achilles Heals in Viral Infections? Cells 2021; 10:cells10092175. [PMID: 34571822 PMCID: PMC8466362 DOI: 10.3390/cells10092175] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/16/2021] [Accepted: 08/20/2021] [Indexed: 12/26/2022] Open
Abstract
As viruses are obligatory intracellular parasites, any step during their life cycle strictly depends on successful interaction with their particular host cells. In particular, their interaction with cellular membranes is of crucial importance for most steps in the viral replication cycle. Such interactions are initiated by uptake of viral particles and subsequent trafficking to intracellular compartments to access their replication compartments which provide a spatially confined environment concentrating viral and cellular components, and subsequently, employ cellular membranes for assembly and exit of viral progeny. The ability of viruses to actively modulate lipid composition such as sphingolipids (SLs) is essential for successful completion of the viral life cycle. In addition to their structural and biophysical properties of cellular membranes, some sphingolipid (SL) species are bioactive and as such, take part in cellular signaling processes involved in regulating viral replication. It is especially due to the progress made in tools to study accumulation and dynamics of SLs, which visualize their compartmentalization and identify interaction partners at a cellular level, as well as the availability of genetic knockout systems, that the role of particular SL species in the viral replication process can be analyzed and, most importantly, be explored as targets for therapeutic intervention.
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Affiliation(s)
- Sibylle Schneider-Schaulies
- Institute for Virology and Immunobiology, University of Wuerzburg, 97078 Würzburg, Germany; (S.S.-S.); (M.S.); (T.W.)
| | - Fabian Schumacher
- Institute of Pharmacy, Pharmacology and Toxicology, Freie Universität Berlin, 14195 Berlin, Germany; (F.S.); (D.W.)
| | - Dominik Wigger
- Institute of Pharmacy, Pharmacology and Toxicology, Freie Universität Berlin, 14195 Berlin, Germany; (F.S.); (D.W.)
| | - Marie Schöl
- Institute for Virology and Immunobiology, University of Wuerzburg, 97078 Würzburg, Germany; (S.S.-S.); (M.S.); (T.W.)
| | - Trushnal Waghmare
- Institute for Virology and Immunobiology, University of Wuerzburg, 97078 Würzburg, Germany; (S.S.-S.); (M.S.); (T.W.)
| | - Jan Schlegel
- Department for Biotechnology and Biophysics, University of Wuerzburg, 97074 Würzburg, Germany;
| | - Jürgen Seibel
- Department for Organic Chemistry, University of Wuerzburg, 97074 Würzburg, Germany;
| | - Burkhard Kleuser
- Institute of Pharmacy, Pharmacology and Toxicology, Freie Universität Berlin, 14195 Berlin, Germany; (F.S.); (D.W.)
- Correspondence: ; Tel.: +49-30-8386-9823
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18
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Backman APE, Mattjus P. Who moves the sphinx? An overview of intracellular sphingolipid transport. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159021. [PMID: 34339859 DOI: 10.1016/j.bbalip.2021.159021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/24/2021] [Accepted: 06/27/2021] [Indexed: 11/28/2022]
Abstract
Lipid bilayers function as boundaries that enclose their content from the surrounding media, and the composition of different membrane types is accurately and dynamically tailored so that they can perform their function. To achieve this balance, lipid biosynthetic machinery and lipid trafficking events are intertwined into an elegant network. In this review, we focus on the intracellular movement of sphingolipids mediated by sphingolipid transfer proteins. Additionally, we will focus on the best characterized and understood mammalian sphingolipid transfer proteins and provide an overview of how they are hypothesized to function. Some are already well understood, while others remain enigmatic. A few are actual lipid transfer proteins, moving lipids from membrane to membrane, while others may have more of a sensor role, possibly reacting to changes in the concentrations of their ligands. Considering the substrates available for cytosolic sphingolipid transfer proteins, one open question that is discussed is whether galactosylceramide is a target. Another question is the exact mechanics by which sphingolipid transfer proteins are targeted to different organelles, such as how four phosphate adapter protein-2, FAPP2 is targeted to the endoplasmic reticulum. The aim of this review is to discuss what is known within the field today and to provide a basic understanding of how these proteins may work.
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Affiliation(s)
- Anders P E Backman
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Peter Mattjus
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland.
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19
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Li HC, Yang CH, Lo SY. Cellular factors involved in the hepatitis C virus life cycle. World J Gastroenterol 2021; 27:4555-4581. [PMID: 34366623 PMCID: PMC8326260 DOI: 10.3748/wjg.v27.i28.4555] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/04/2021] [Accepted: 07/09/2021] [Indexed: 02/06/2023] Open
Abstract
The hepatitis C virus (HCV), an obligatory intracellular pathogen, highly depends on its host cells to propagate successfully. The HCV life cycle can be simply divided into several stages including viral entry, protein translation, RNA replication, viral assembly and release. Hundreds of cellular factors involved in the HCV life cycle have been identified over more than thirty years of research. Characterization of these cellular factors has provided extensive insight into HCV replication strategies. Some of these cellular factors are targets for anti-HCV therapies. In this review, we summarize the well-characterized and recently identified cellular factors functioning at each stage of the HCV life cycle.
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Affiliation(s)
- Hui-Chun Li
- Department of Biochemistry, Tzu Chi University, Hualien 970, Taiwan
| | - Chee-Hing Yang
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
| | - Shih-Yen Lo
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 970, Taiwan
- Department of Laboratory Medicine, Buddhist Tzu Chi General Hospital, Hualien 970, Taiwan
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20
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Avula K, Singh B, Kumar PV, Syed GH. Role of Lipid Transfer Proteins (LTPs) in the Viral Life Cycle. Front Microbiol 2021; 12:673509. [PMID: 34248884 PMCID: PMC8260984 DOI: 10.3389/fmicb.2021.673509] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/17/2021] [Indexed: 12/14/2022] Open
Abstract
Viruses are obligate parasites that depend on the host cell machinery for their replication and dissemination. Cellular lipids play a central role in multiple stages of the viral life cycle such as entry, replication, morphogenesis, and egress. Most viruses reorganize the host cell membranes for the establishment of viral replication complex. These specialized structures allow the segregation of replicating viral RNA from ribosomes and protect it from host nucleases. They also facilitate localized enrichment of cellular components required for viral replication and assembly. The specific composition of the lipid membrane governs its ability to form negative or positive curvature and possess a rigid or flexible form, which is crucial for membrane rearrangement and establishment of viral replication complexes. In this review, we highlight how different viruses manipulate host lipid transfer proteins and harness their functions to enrich different membrane compartments with specific lipids in order to facilitate multiple aspects of the viral life cycle.
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Affiliation(s)
- Kiran Avula
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India.,Regional Centre for Biotechnology, Faridabad, India
| | - Bharati Singh
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India.,School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneshwar, India
| | - Preethy V Kumar
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India.,School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneshwar, India
| | - Gulam H Syed
- Virus-Host Interaction Lab, Institute of Life Sciences, Bhubaneshwar, India
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21
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Potential pharmacological strategies targeting the Niemann-Pick C1 receptor and Ebola virus glycoprotein interaction. Eur J Med Chem 2021; 223:113654. [PMID: 34175537 DOI: 10.1016/j.ejmech.2021.113654] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/27/2021] [Accepted: 06/13/2021] [Indexed: 10/21/2022]
Abstract
Niemann-Pick C1 (NPC1) receptor is an intracellular protein located in late endosomes and lysosomes whose main function is to regulate intracellular cholesterol trafficking. Besides being postulated as necessary for the infection of highly pathogenic viruses in which the integrity of cholesterol transport is required, this protein also allows the entry of the Ebola virus (EBOV) into the host cells acting as an intracellular receptor. EBOV glycoprotein (EBOV-GP) interaction with NPC1 at the endosomal membrane triggers the release of the viral material into the host cell, starting the infective cycle. Disruption of the NPC1/EBOV-GP interaction could represent an attractive strategy for the development of drugs aimed at inhibiting viral entry and thus infection. Some of the today available EBOV inhibitors were proposed to interrupt this interaction, but molecular and structural details about their mode of action are still preliminary thus more efforts are needed to properly address these points. Here, we provide a critical discussion of the potential of NPC1 and its interaction with EBOV-GP as a therapeutic target for viral infections.
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22
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Hepatitis C Virus Uses Host Lipids to Its Own Advantage. Metabolites 2021; 11:metabo11050273. [PMID: 33925362 PMCID: PMC8145847 DOI: 10.3390/metabo11050273] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/11/2021] [Accepted: 04/23/2021] [Indexed: 02/06/2023] Open
Abstract
Lipids and lipoproteins constitute indispensable components for living not only for humans. In the case of hepatitis C virus (HCV), the option of using the products of our lipid metabolism is “to be, or not to be”. On the other hand, HCV infection, which is the main cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma, exerts a profound influence on lipid and lipoprotein metabolism of the host. The consequences of this alternation are frequently observed as hypolipidemia and hepatic steatosis in chronic hepatitis C (CHC) patients. The clinical relevance of these changes reflects the fact that lipids and lipoprotein play a crucial role in all steps of the life cycle of HCV. The virus circulates in the bloodstream as a highly lipidated lipo-viral particle (LVP) that defines HCV hepatotropism. Thus, strict relationships between lipids/lipoproteins and HCV are indispensable for the mechanism of viral entry into hepatocytes, viral replication, viral particles assembly and secretion. The purpose of this review is to summarize the tricks thanks to which HCV utilizes host lipid metabolism to its own advantage.
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Li HC, Yang CH, Lo SY. Hepatitis C Viral Replication Complex. Viruses 2021; 13:v13030520. [PMID: 33809897 PMCID: PMC8004249 DOI: 10.3390/v13030520] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 12/16/2022] Open
Abstract
The life cycle of the hepatitis C virus (HCV) can be divided into several stages, including viral entry, protein translation, RNA replication, viral assembly, and release. HCV genomic RNA replication occurs in the replication organelles (RO) and is tightly linked to ER membrane alterations containing replication complexes (proteins NS3 to NS5B). The amplification of HCV genomic RNA could be regulated by the RO biogenesis, the viral RNA structure (i.e., cis-acting replication elements), and both viral and cellular proteins. Studies on HCV replication have led to the development of direct-acting antivirals (DAAs) targeting the replication complex. This review article summarizes the viral and cellular factors involved in regulating HCV genomic RNA replication and the DAAs that inhibit HCV replication.
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Affiliation(s)
- Hui-Chun Li
- Department of Biochemistry, Tzu Chi University, Hualien 97004, Taiwan;
| | - Chee-Hing Yang
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 97004, Taiwan;
| | - Shih-Yen Lo
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien 97004, Taiwan;
- Department of Laboratory Medicine, Buddhist Tzu Chi General Hospital, Hualien 97004, Taiwan
- Correspondence: ; Tel.: +886-3-8565301 (ext. 2322)
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24
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Wong LH, Edgar JR, Martello A, Ferguson BJ, Eden ER. Exploiting Connections for Viral Replication. Front Cell Dev Biol 2021; 9:640456. [PMID: 33816489 PMCID: PMC8012536 DOI: 10.3389/fcell.2021.640456] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/01/2021] [Indexed: 12/16/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the COVID-19 (coronavirus disease 2019) pandemic, is a positive strand RNA (+RNA) virus. Like other +RNA viruses, SARS-CoV-2 is dependent on host cell metabolic machinery to survive and replicate, remodeling cellular membranes to generate sites of viral replication. Viral RNA-containing double-membrane vesicles (DMVs) are a striking feature of +RNA viral replication and are abundant in SARS-CoV-2-infected cells. Their generation involves rewiring of host lipid metabolism, including lipid biosynthetic pathways. Viruses can also redirect lipids from host cell organelles; lipid exchange at membrane contact sites, where the membranes of adjacent organelles are in close apposition, has been implicated in the replication of several +RNA viruses. Here we review current understanding of DMV biogenesis. With a focus on the exploitation of contact site machinery by +RNA viruses to generate replication organelles, we discuss evidence that similar mechanisms support SARS-CoV-2 replication, protecting its RNA from the host cell immune response.
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Affiliation(s)
| | - James R. Edgar
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | | | - Brian J. Ferguson
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Emily R. Eden
- UCL Institute of Ophthalmology, London, United Kingdom
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Vitner EB, Achdout H, Avraham R, Politi B, Cherry L, Tamir H, Yahalom-Ronen Y, Paran N, Melamed S, Erez N, Israely T. Glucosylceramide synthase inhibitors prevent replication of SARS-CoV-2 and influenza virus. J Biol Chem 2021; 296:100470. [PMID: 33639165 PMCID: PMC7904475 DOI: 10.1016/j.jbc.2021.100470] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/20/2021] [Accepted: 02/23/2021] [Indexed: 12/13/2022] Open
Abstract
The ongoing COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a major threat to global health. Vaccines are ideal solutions to prevent infection, but treatments are also needed for those who have contracted the virus to limit negative outcomes, when vaccines are not applicable. Viruses must cross host cell membranes during their life cycle, creating a dependency on processes involving membrane dynamics. Thus, in this study, we examined whether the synthetic machinery for glycosphingolipids, biologically active components of cell membranes, can serve as a therapeutic target to combat SARS-CoV-2. We examined the antiviral effect of two specific inhibitors of glucosylceramide synthase (GCS): (i) Genz-123346, an analogue of the United States Food and Drug Administration-approved drug Cerdelga and (ii) GENZ-667161, an analogue of venglustat, which is currently under phase III clinical trials. We found that both GCS inhibitors inhibit replication of SARS-CoV-2. Moreover, these inhibitors also disrupt replication of influenza virus A/PR/8/34 (H1N1). Our data imply that synthesis of glycosphingolipids is necessary to support viral life cycles and suggest that GCS inhibitors should be further explored as antiviral therapies.
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Affiliation(s)
- Einat B Vitner
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel.
| | - Hagit Achdout
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Roy Avraham
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Boaz Politi
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Lilach Cherry
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Hadas Tamir
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Yfat Yahalom-Ronen
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Nir Paran
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Sharon Melamed
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Noam Erez
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Tomer Israely
- Departments of Infectious Diseases, Israel Institute for Biological Research, Ness-Ziona, Israel
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26
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Avota E, Bodem J, Chithelen J, Mandasari P, Beyersdorf N, Schneider-Schaulies J. The Manifold Roles of Sphingolipids in Viral Infections. Front Physiol 2021. [PMID: 34658908 DOI: 10.3389/fphys.2021.71552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023] Open
Abstract
Sphingolipids are essential components of eukaryotic cells. In this review, we want to exemplarily illustrate what is known about the interactions of sphingolipids with various viruses at different steps of their replication cycles. This includes structural interactions during entry at the plasma membrane or endosomal membranes, early interactions leading to sphingolipid-mediated signal transduction, interactions with internal membranes and lipids during replication, and interactions during virus assembly and budding. Targeted interventions in sphingolipid metabolism - as far as they can be tolerated by cells and organisms - may open novel possibilities to support antiviral therapies. Human immunodeficiency virus type 1 (HIV-1) infections have intensively been studied, but for other viral infections, such as influenza A virus (IAV), measles virus (MV), hepatitis C virus (HCV), dengue virus, Ebola virus, and severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), investigations are still in their beginnings. As many inhibitors of sphingolipid metabolism are already in clinical use against other diseases, repurposing studies for applications in some viral infections appear to be a promising approach.
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Affiliation(s)
- Elita Avota
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Jochen Bodem
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Janice Chithelen
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Putri Mandasari
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Niklas Beyersdorf
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
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27
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Balgoma D, Gil-de-Gómez L, Montero O. Lipidomics Issues on Human Positive ssRNA Virus Infection: An Update. Metabolites 2020; 10:E356. [PMID: 32878290 PMCID: PMC7569815 DOI: 10.3390/metabo10090356] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 12/29/2022] Open
Abstract
The pathogenic mechanisms underlying the Biology and Biochemistry of viral infections are known to depend on the lipid metabolism of infected cells. From a lipidomics viewpoint, there are a variety of mechanisms involving virus infection that encompass virus entry, the disturbance of host cell lipid metabolism, and the role played by diverse lipids in regard to the infection effectiveness. All these aspects have currently been tackled separately as independent issues and focused on the function of proteins. Here, we review the role of cholesterol and other lipids in ssRNA+ infection.
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Affiliation(s)
- David Balgoma
- Analytical Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala University, Husarg. 3, 75123 Uppsala, Sweden;
| | - Luis Gil-de-Gómez
- Center of Childhood Cancer Center, Children’s Hospital of Philadelphia, Colket Translational Research Center, 3501 Civic Center Blvd, Philadelphia, PA 19104, USA;
| | - Olimpio Montero
- Spanish National Research Council (CSIC), Boecillo’s Technological Park Bureau, Av. Francisco Vallés 8, 47151 Boecillo, Spain
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28
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Dadhich R, Kapoor S. Various Facets of Pathogenic Lipids in Infectious Diseases: Exploring Virulent Lipid-Host Interactome and Their Druggability. J Membr Biol 2020; 253:399-423. [PMID: 32833058 PMCID: PMC7443855 DOI: 10.1007/s00232-020-00135-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 08/12/2020] [Indexed: 02/07/2023]
Abstract
Lipids form an integral, structural, and functional part of all life forms. They play a significant role in various cellular processes such as membrane fusion, fission, endocytosis, protein trafficking, and protein functions. Interestingly, recent studies have revealed their more impactful and critical involvement in infectious diseases, starting with the manipulation of the host membrane to facilitate pathogenic entry. Thereafter, pathogens recruit specific host lipids for the maintenance of favorable intracellular niche to augment their survival and proliferation. In this review, we showcase the lipid-mediated host pathogen interplay in context of life-threatening viral and bacterial diseases including the recent SARS-CoV-2 infection. We evaluate the emergent lipid-centric approaches adopted by these pathogens, while delineating the alterations in the composition and organization of the cell membrane within the host, as well as the pathogen. Lastly, crucial nexus points in their interaction landscape for therapeutic interventions are identified. Lipids act as critical determinants of bacterial and viral pathogenesis by altering the host cell membrane structure and functions.
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Affiliation(s)
- Ruchika Dadhich
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India.
| | - Shobhna Kapoor
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India.
- Wadhwani Research Centre for Bioengineering, Indian Institute of Technology Bombay, Mumbai, 400076, India.
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29
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Abstract
Viruses manipulate cellular lipids and membranes at each stage of their life cycle. This includes lipid-receptor interactions, the fusion of viral envelopes with cellular membranes during endocytosis, the reorganization of cellular membranes to form replication compartments, and the envelopment and egress of virions. In addition to the physical interactions with cellular membranes, viruses have evolved to manipulate lipid signaling and metabolism to benefit their replication. This review summarizes the strategies that viruses use to manipulate lipids and membranes at each stage in the viral life cycle.
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Affiliation(s)
- Ellen Ketter
- Department of Microbiology, The University of Chicago, Chicago, Illinois 60637, USA;
| | - Glenn Randall
- Department of Microbiology, The University of Chicago, Chicago, Illinois 60637, USA;
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30
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Mishra SK, Gao YG, Zou X, Stephenson DJ, Malinina L, Hinchcliffe EH, Chalfant CE, Brown RE. Emerging roles for human glycolipid transfer protein superfamily members in the regulation of autophagy, inflammation, and cell death. Prog Lipid Res 2020; 78:101031. [PMID: 32339554 DOI: 10.1016/j.plipres.2020.101031] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/27/2020] [Accepted: 02/27/2020] [Indexed: 12/14/2022]
Abstract
Glycolipid transfer proteins (GLTPs) were first identified over three decades ago as ~24kDa, soluble, amphitropic proteins that specifically accelerate the intermembrane transfer of glycolipids. Upon discovery that GLTPs use a unique, all-α-helical, two-layer 'sandwich' architecture (GLTP-fold) to bind glycosphingolipids (GSLs), a new protein superfamily was born. Structure/function studies have provided exquisite insights defining features responsible for lipid headgroup selectivity and hydrophobic 'pocket' adaptability for accommodating hydrocarbon chains of differing length and unsaturation. In humans, evolutionarily-modified GLTP-folds have been identified with altered sphingolipid specificity, e. g. ceramide-1-phosphate transfer protein (CPTP), phosphatidylinositol 4-phosphate adaptor protein-2 (FAPP2) which harbors a GLTP-domain and GLTPD2. Despite the wealth of structural data (>40 Protein Data Bank deposits), insights into the in vivo functional roles of GLTP superfamily members have emerged slowly. In this review, recent advances are presented and discussed implicating human GLTP superfamily members as important regulators of: i) pro-inflammatory eicosanoid production associated with Group-IV cytoplasmic phospholipase A2; ii) autophagy and inflammasome assembly that drive surveillance cell release of interleukin-1β and interleukin-18 inflammatory cytokines; iii) cell cycle arrest and necroptosis induction in certain colon cancer cell lines. The effects exerted by GLTP superfamily members appear linked to their ability to regulate sphingolipid homeostasis by acting in either transporter and/or sensor capacities. These timely findings are opening new avenues for future cross-disciplinary, translational medical research involving GLTP-fold proteins in human health and disease. Such avenues include targeted regulation of specific GLTP superfamily members to alter sphingolipid levels as a therapeutic means for combating viral infection, neurodegenerative conditions and circumventing chemo-resistance during cancer treatment.
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Affiliation(s)
- Shrawan K Mishra
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Yong-Guang Gao
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Xianqiong Zou
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Daniel J Stephenson
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University Medical Center, Richmond, VA 23298-0614, USA; Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA
| | - Lucy Malinina
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | | | - Charles E Chalfant
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA; Research Service, James A. Haley Veterans Hospital, Tampa, FL 33612, USA; The Moffitt Cancer Center, Tampa, FL 33620, USA
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31
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Tabata K, Neufeldt CJ, Bartenschlager R. Hepatitis C Virus Replication. Cold Spring Harb Perspect Med 2020; 10:cshperspect.a037093. [PMID: 31570388 DOI: 10.1101/cshperspect.a037093] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Replication and amplification of the viral genome is a key process for all viruses. For hepatitis C virus (HCV), a positive-strand RNA virus, amplification of the viral genome requires the synthesis of a negative-sense RNA template, which is in turn used for the production of new genomic RNA. This process is governed by numerous proteins, both host and viral, as well as distinct lipids and specific RNA elements within the positive- and negative-strand RNAs. Moreover, this process requires specific changes to host cell ultrastructure to create microenvironments conducive to viral replication. This review will focus on describing the processes and factors involved in facilitating or regulating HCV genome replication.
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Affiliation(s)
- Keisuke Tabata
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Christopher J Neufeldt
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany.,Division of Virus-Associated Carcinogenesis, German Cancer Research Center, 69120 Heidelberg, Germany.,German Center for Infection Research, Heidelberg Partner Site, 69120 Heidelberg, Germany
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32
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Nir2 Is an Effector of VAPs Necessary for Efficient Hepatitis C Virus Replication and Phosphatidylinositol 4-Phosphate Enrichment at the Viral Replication Organelle. J Virol 2019; 93:JVI.00742-19. [PMID: 31484747 DOI: 10.1128/jvi.00742-19] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 08/28/2019] [Indexed: 01/19/2023] Open
Abstract
The endoplasmic reticulum (ER)-resident proteins vesicle-associated membrane protein (VAMP)-associated protein A and B (VAPA and VAPB) have been reported to be necessary for efficient hepatitis C virus (HCV) replication, but the specific mechanisms are not well understood. VAPs are known to recruit lipid transfer proteins to the ER, including oxysterol binding protein (OSBP), which has been previously shown to be necessary for cholesterol delivery to the HCV replication organelle in exchange for phosphatidylinositol 4-phosphate [PI(4)P]. Here, we show that VAPA and VAPB are redundant for HCV infection and that dimerization is not required for their function. In addition, we identify the phosphatidylinositol transfer protein Nir2 as an effector of VAPs to support HCV replication. We propose that Nir2 functions to replenish phosphoinositides at the HCV replication organelle to maintain elevated steady-state levels of PI(4)P, which is removed by OSBP. Thus, Nir2, along with VAPs, OSBP, and the phosphatidylinositol 4-kinase, completes a cycle of phosphoinositide flow between the ER and viral replication organelles to drive ongoing viral replication.IMPORTANCE Hepatitis C virus (HCV) is known for its ability to modulate phosphoinositide signaling pathways for its replication. Elevated levels of phosphatidylinositol 4-phosphate [PI(4)P] in HCV replication organelles (ROs) recruits lipid transfer proteins (LTPs), like oxysterol-binding protein (OSBP). OSBP exchanges PI(4)P with cholesterol, thus removing PI(4)P from the HCV RO. Here, we found that the phosphatidylinositol transfer protein Nir2 acts as an LTP and may replenish PI at the HCV RO by interacting with VAMP-associated proteins (VAPs), enabling continuous viral replication during chronic infection. Therefore, the coordination of OSBP, Nir2, and VAPs completes our understanding of the phosphoinositide cycle between the ER and HCV ROs.
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33
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Yager EJ, Konan KV. Sphingolipids as Potential Therapeutic Targets against Enveloped Human RNA Viruses. Viruses 2019; 11:v11100912. [PMID: 31581580 PMCID: PMC6832137 DOI: 10.3390/v11100912] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/27/2019] [Accepted: 09/28/2019] [Indexed: 12/28/2022] Open
Abstract
Several notable human diseases are caused by enveloped RNA viruses: influenza, AIDS, hepatitis C, dengue hemorrhagic fever, microcephaly, and Guillain-Barré Syndrome. Being enveloped, the life cycle of this group of viruses is critically dependent on host lipid biosynthesis. Viral binding and entry involve interactions between viral envelope glycoproteins and cellular receptors localized to lipid-rich regions of the plasma membrane. Subsequent infection by these viruses leads to reorganization of cellular membranes and lipid metabolism to support the production of new viral particles. Recent work has focused on defining the involvement of specific lipid classes in the entry, genome replication assembly, and viral particle formation of these viruses in hopes of identifying potential therapeutic targets for the treatment or prevention of disease. In this review, we will highlight the role of host sphingolipids in the lifecycle of several medically important enveloped RNA viruses.
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Affiliation(s)
- Eric J Yager
- Department of Basic and Clinical Sciences, Albany College of Pharmacy and Health Sciences, Albany, NY 12208, USA.
| | - Kouacou V Konan
- Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY 12208-3479, USA.
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Neufeldt CJ, Cortese M, Acosta EG, Bartenschlager R. Rewiring cellular networks by members of the Flaviviridae family. Nat Rev Microbiol 2019; 16:125-142. [PMID: 29430005 PMCID: PMC7097628 DOI: 10.1038/nrmicro.2017.170] [Citation(s) in RCA: 247] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Members of the Flaviviridae virus family comprise a large group of enveloped viruses with a single-strand RNA genome of positive polarity. Several genera belong to this family, including the Hepacivirus genus, of which hepatitis C virus (HCV) is the prototype member, and the Flavivirus genus, which contains both dengue virus and Zika virus. Viruses of these genera differ in many respects, such as the mode of transmission or the course of infection, which is either predominantly persistent in the case of HCV or acutely self-limiting in the case of flaviviruses. Although the fundamental replication strategy of Flaviviridae members is similar, during the past few years, important differences have been discovered, including the way in which these viruses exploit cellular resources to facilitate viral propagation. These differences might be responsible, at least in part, for the various biological properties of these viruses, thus offering the possibility to learn from comparisons. In this Review, we discuss the current understanding of how Flaviviridae viruses manipulate and usurp cellular pathways in infected cells. Specifically, we focus on comparing strategies employed by flaviviruses with those employed by hepaciviruses, and we discuss the importance of these interactions in the context of viral replication and antiviral therapies.
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Affiliation(s)
- Christopher J Neufeldt
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Mirko Cortese
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Eliana G Acosta
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany
| | - Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, 69120 Heidelberg, Germany.,German Center for Infection Research, Heidelberg Partner Site, 69120 Heidelberg, Germany
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35
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Samaha D, Hamdo HH, Wilde M, Prause K, Arenz C. Sphingolipid-Transporting Proteins as Cancer Therapeutic Targets. Int J Mol Sci 2019; 20:ijms20143554. [PMID: 31330821 PMCID: PMC6678544 DOI: 10.3390/ijms20143554] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 07/16/2019] [Accepted: 07/18/2019] [Indexed: 01/11/2023] Open
Abstract
The understanding of the role of sphingolipid metabolism in cancer has tremendously increased in the past ten years. Many tumors are characterized by imbalances in sphingolipid metabolism. In many cases, disorders of sphingolipid metabolism are also likely to cause or at least promote cancer. In this review, sphingolipid transport proteins and the processes catalyzed by them are regarded as essential components of sphingolipid metabolism. There is much to suggest that these processes are often rate-limiting steps for metabolism of individual sphingolipid species and thus represent potential target structures for pharmaceutical anticancer research. Here, we summarize empirical and biochemical data on different proteins with key roles in sphingolipid transport and their potential role in cancer.
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Affiliation(s)
- Doaa Samaha
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
- Depatment of Pharmaceutical Chemistry, College of Pharmacy, Helwan University, Cairo 11795, Egypt
| | - Housam H Hamdo
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Max Wilde
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Kevin Prause
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Christoph Arenz
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany.
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36
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Lipid exchange and signaling at ER–Golgi contact sites. Curr Opin Cell Biol 2019; 57:8-15. [DOI: 10.1016/j.ceb.2018.10.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 10/14/2018] [Accepted: 10/16/2018] [Indexed: 01/24/2023]
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37
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Functional and Physical Interaction between the Arf Activator GBF1 and Hepatitis C Virus NS3 Protein. J Virol 2019; 93:JVI.01459-18. [PMID: 30567983 DOI: 10.1128/jvi.01459-18] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 12/14/2018] [Indexed: 12/11/2022] Open
Abstract
GBF1 has emerged as a host factor required for the genome replication of RNA viruses of different families. During the hepatitis C virus (HCV) life cycle, GBF1 performs a critical function at the onset of genome replication but is dispensable when the replication is established. To better understand how GBF1 regulates HCV infection, we have looked for interactions between GBF1 and HCV proteins. NS3 was found to interact with GBF1 in yeast two-hybrid, coimmunoprecipitation, and proximity ligation assays and to interfere with GBF1 function and alter GBF1 intracellular localization in cells expressing NS3. The interaction was mapped to the Sec7 domain of GBF1 and the protease domain of NS3. A reverse yeast two-hybrid screen to identify mutations altering NS3-GBF1 interaction yielded an NS3 mutant (N77D, Con1 strain) that is nonreplicative despite conserved protease activity and does not interact with GBF1. The mutated residue is exposed at the surface of NS3, suggesting it is part of the domain of NS3 that interacts with GBF1. The corresponding mutation in strain JFH-1 (S77D) produces a similar phenotype. Our results provide evidence for an interaction between NS3 and GBF1 and suggest that an alteration of this interaction is detrimental to HCV genome replication.IMPORTANCE Single-stranded, positive-sense RNA viruses rely to a significant extent on host factors to achieve the replication of their genome. GBF1 is such a cellular protein that is required for the replication of several RNA viruses, but its mechanism of action during viral infections is not yet defined. In this study, we investigated potential interactions that GBF1 might engage in with proteins of HCV, a GBF1-dependent virus. We found that GBF1 interacts with NS3, a nonstructural protein involved in HCV genome replication, and our results suggest that this interaction is important for GBF1 function during HCV replication. Interestingly, GBF1 interaction with HCV appears different from its interaction with enteroviruses, another group of GBF1-dependent RNA viruses, in keeping with the fact that HCV and enteroviruses use different functions of GBF1.
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Zhang Z, He G, Filipowicz NA, Randall G, Belov GA, Kopek BG, Wang X. Host Lipids in Positive-Strand RNA Virus Genome Replication. Front Microbiol 2019; 10:286. [PMID: 30863375 PMCID: PMC6399474 DOI: 10.3389/fmicb.2019.00286] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 02/04/2019] [Indexed: 12/19/2022] Open
Abstract
Membrane association is a hallmark of the genome replication of positive-strand RNA viruses [(+)RNA viruses]. All well-studied (+)RNA viruses remodel host membranes and lipid metabolism through orchestrated virus-host interactions to create a suitable microenvironment to survive and thrive in host cells. Recent research has shown that host lipids, as major components of cellular membranes, play key roles in the replication of multiple (+)RNA viruses. This review focuses on how (+)RNA viruses manipulate host lipid synthesis and metabolism to facilitate their genomic RNA replication, and how interference with the cellular lipid metabolism affects viral replication.
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Affiliation(s)
- Zhenlu Zhang
- National Key Laboratory of Crop Biology, National Research Center for Apple Engineering and Technology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, China
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Guijuan He
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA, United States
- Fujian Province Key Laboratory of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
| | | | - Glenn Randall
- Department of Microbiology, The University of Chicago, Chicago, IL, United States
| | - George A. Belov
- Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, MD, United States
| | | | - Xiaofeng Wang
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA, United States
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Fernández-Oliva A, Ortega-González P, Risco C. Targeting host lipid flows: Exploring new antiviral and antibiotic strategies. Cell Microbiol 2019; 21:e12996. [PMID: 30585688 PMCID: PMC7162424 DOI: 10.1111/cmi.12996] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/04/2018] [Accepted: 12/17/2018] [Indexed: 12/28/2022]
Abstract
Bacteria and viruses pose serious challenges for humans because they evolve continuously. Despite ongoing efforts, antiviral drugs to treat many of the most troubling viruses have not been approved yet. The recent launch of new antimicrobials is generating hope as more and more pathogens around the world become resistant to available drugs. But extra effort is still needed. One of the current strategies for antiviral and antibiotic drug development is the search for host cellular pathways used by many different pathogens. For example, many viruses and bacteria alter lipid synthesis and transport to build their own organelles inside infected cells. The characterization of these interactions will be fundamental to identify new targets for antiviral and antibiotic drug development. This review discusses how viruses and bacteria subvert cell machineries for lipid synthesis and transport and summarises the most promising compounds that interfere with these pathways.
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Affiliation(s)
| | | | - Cristina Risco
- Cell Structure Lab, National Centre for Biotechnology, CNB-CSIC, Madrid, Spain
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40
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Robinson M, Schor S, Barouch-Bentov R, Einav S. Viral journeys on the intracellular highways. Cell Mol Life Sci 2018; 75:3693-3714. [PMID: 30043139 PMCID: PMC6151136 DOI: 10.1007/s00018-018-2882-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/01/2018] [Accepted: 07/19/2018] [Indexed: 12/24/2022]
Abstract
Viruses are obligate intracellular pathogens that are dependent on cellular machineries for their replication. Recent technological breakthroughs have facilitated reliable identification of host factors required for viral infections and better characterization of the virus-host interplay. While these studies have revealed cellular machineries that are uniquely required by individual viruses, accumulating data also indicate the presence of broadly required mechanisms. Among these overlapping cellular functions are components of intracellular membrane trafficking pathways. Here, we review recent discoveries focused on how viruses exploit intracellular membrane trafficking pathways to promote various stages of their life cycle, with an emphasis on cellular factors that are usurped by a broad range of viruses. We describe broadly required components of the endocytic and secretory pathways, the Endosomal Sorting Complexes Required for Transport pathway, and the autophagy pathway. Identification of such overlapping host functions offers new opportunities to develop broad-spectrum host-targeted antiviral strategies.
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Affiliation(s)
- Makeda Robinson
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
| | - Stanford Schor
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA
| | - Rina Barouch-Bentov
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA
| | - Shirit Einav
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Lane Building, Rm L127, Stanford, CA, 94305, USA.
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA.
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41
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Bartenschlager R, Baumert TF, Bukh J, Houghton M, Lemon SM, Lindenbach BD, Lohmann V, Moradpour D, Pietschmann T, Rice CM, Thimme R, Wakita T. Critical challenges and emerging opportunities in hepatitis C virus research in an era of potent antiviral therapy: Considerations for scientists and funding agencies. Virus Res 2018; 248:53-62. [PMID: 29477639 DOI: 10.1016/j.virusres.2018.02.016] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 02/16/2018] [Accepted: 02/19/2018] [Indexed: 12/19/2022]
Abstract
The development and clinical implementation of direct-acting antivirals (DAAs) has revolutionized the treatment of chronic hepatitis C. Infection with any hepatitis C virus (HCV) genotype can now be eliminated in more than 95% of patients with short courses of all-oral, well-tolerated drugs, even in those with advanced liver disease and liver transplant recipients. DAAs have proven so successful that some now consider HCV amenable to eradication, and continued research on the virus of little remaining medical relevance. However, given 400,000 HCV-related deaths annually important challenges remain, including identifying those who are infected, providing access to treatment and reducing its costs. Moreover, HCV infection rarely induces sterilizing immunity, and those who have been cured with DAAs remain at risk for reinfection. Thus, it is very unlikely that global eradication and elimination of the cancer risk associated with HCV infection can be achieved without a vaccine, yet research in that direction receives little attention. Further, over the past two decades HCV research has spearheaded numerous fundamental discoveries in the fields of molecular and cell biology, immunology and microbiology. It will continue to do so, given the unique opportunities afforded by the reagents and knowledge base that have been generated in the development and clinical application of DAAs. Considering these critical challenges and new opportunities, we conclude that funding for HCV research must be sustained.
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Affiliation(s)
- Ralf Bartenschlager
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany; Division Virus-Associated Carcinogenesis, German Cancer Research Center, Heidelberg, Germany; German Centre for Infection Research (DZIF), Partner Sites Heidelberg and Hannover-Braunschweig, Germany.
| | - Thomas F Baumert
- Institut National de la Santé et de la Recherche Médicale, U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Strasbourg, France; Université de Strasbourg, Strasbourg, Institut Hospitalo-Universitaire, Pôle Hépato-digestif, Nouvel Hôpital Civil, Strasbourg, France
| | - Jens Bukh
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital and Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Michael Houghton
- Li Ka Shing Institute of Virology, Department of Medical Microbiology & Immunology, University of Alberta, Edmonton, Canada
| | - Stanley M Lemon
- Departments of Medicine and Microbiology & Immunology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC, USA
| | - Brett D Lindenbach
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Volker Lohmann
- Department of Infectious Diseases, Molecular Virology, Heidelberg University, Heidelberg, Germany
| | - Darius Moradpour
- Division of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Switzerland
| | - Thomas Pietschmann
- German Centre for Infection Research (DZIF), Partner Sites Heidelberg and Hannover-Braunschweig, Germany; Institute of Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research (a joint venture between the Medical School Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI)), Hannover, Germany
| | - Charles M Rice
- Laboratory of Virology and Infectious Disease, Center for the Study of Hepatitis C, The Rockefeller University, New York, NY, USA
| | - Robert Thimme
- Center for Medicine, Department of Medicine II, Medical Center - University of Freiburg, Germany
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
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42
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Hepatitis C Virus Replication Depends on Endosomal Cholesterol Homeostasis. J Virol 2017; 92:JVI.01196-17. [PMID: 29046459 DOI: 10.1128/jvi.01196-17] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 09/28/2017] [Indexed: 01/16/2023] Open
Abstract
Similar to other positive-strand RNA viruses, hepatitis C virus (HCV) causes massive rearrangements of intracellular membranes, resulting in a membranous web (MW) composed of predominantly double-membrane vesicles (DMVs), the presumed sites of RNA replication. DMVs are enriched for cholesterol, but mechanistic details on the source and recruitment of cholesterol to the viral replication organelle are only partially known. Here we focused on selected lipid transfer proteins implicated in direct lipid transfer at various endoplasmic reticulum (ER)-membrane contact sites. RNA interference (RNAi)-mediated knockdown identified several hitherto unknown HCV dependency factors, such as steroidogenic acute regulatory protein-related lipid transfer domain protein 3 (STARD3), oxysterol-binding protein-related protein 1A and -B (OSBPL1A and -B), and Niemann-Pick-type C1 (NPC1), all residing at late endosome and lysosome membranes and required for efficient HCV RNA replication but not for replication of the closely related dengue virus. Focusing on NPC1, we found that knockdown or pharmacological inhibition caused cholesterol entrapment in lysosomal vesicles concomitant with decreased cholesterol abundance at sites containing the viral replicase factor NS5A. In untreated HCV-infected cells, unesterified cholesterol accumulated at the perinuclear region, partially colocalizing with NS5A at DMVs, arguing for NPC1-mediated endosomal cholesterol transport to the viral replication organelle. Consistent with cholesterol being an important structural component of DMVs, reducing NPC1-dependent endosomal cholesterol transport impaired MW integrity. This suggests that HCV usurps lipid transfer proteins, such as NPC1, at ER-late endosome/lysosome membrane contact sites to recruit cholesterol to the viral replication organelle, where it contributes to MW functionality.IMPORTANCE A key feature of the replication of positive-strand RNA viruses is the rearrangement of the host cell endomembrane system to produce a membranous replication organelle (RO). The underlying mechanisms are far from being elucidated fully. In this report, we provide evidence that HCV RNA replication depends on functional lipid transport along the endosomal-lysosomal pathway that is mediated by several lipid transfer proteins, such as the Niemann-Pick type C1 (NPC1) protein. Pharmacological inhibition of NPC1 function reduced viral replication, impaired the transport of cholesterol to the viral replication organelle, and altered organelle morphology. Besides NPC1, our study reports the importance of additional endosomal and lysosomal lipid transfer proteins required for viral replication, thus contributing to our understanding of how HCV manipulates their function in order to generate a membranous replication organelle. These results might have implications for the biogenesis of replication organelles of other positive-strand RNA viruses.
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43
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Zhang J, Lan Y, Sanyal S. Modulation of Lipid Droplet Metabolism-A Potential Target for Therapeutic Intervention in Flaviviridae Infections. Front Microbiol 2017; 8:2286. [PMID: 29234310 PMCID: PMC5712332 DOI: 10.3389/fmicb.2017.02286] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/06/2017] [Indexed: 12/21/2022] Open
Abstract
Lipid droplets (LDs) are endoplasmic reticulum (ER)-related dynamic organelles that store and regulate fatty acids and neutral lipids. They play a central role in cellular energy storage, lipid metabolism and cellular homeostasis. It has become evident that viruses have co-evolved in order to exploit host lipid metabolic pathways. This is especially characteristic of the Flaviviridae family, including hepatitis C virus (HCV) and several flaviviruses. Devoid of an appropriate lipid biosynthetic machinery of their own, these single-strand positive-sense RNA viruses can induce dramatic changes in host metabolic pathways to establish a favorable environment for viral multiplication and acquire essential components to facilitate their assembly and traffic. Here we have reviewed the current knowledge on the intracellular life cycle of those from the Flaviviridae family, with particular emphasis on HCV and dengue virus (DENV), and their association with the biosynthesis and metabolism of LDs, with the aim to identify potential antiviral targets for development of novel therapeutic interventions.
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Affiliation(s)
- Jingshu Zhang
- HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Yun Lan
- HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Sumana Sanyal
- HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China.,School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
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Hepatitis C Virus Subverts Human Choline Kinase-α To Bridge Phosphatidylinositol-4-Kinase IIIα (PI4KIIIα) and NS5A and Upregulates PI4KIIIα Activation, Thereby Promoting the Translocation of the Ternary Complex to the Endoplasmic Reticulum for Viral Replication. J Virol 2017; 91:JVI.00355-17. [PMID: 28566381 PMCID: PMC5533930 DOI: 10.1128/jvi.00355-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 05/25/2017] [Indexed: 12/20/2022] Open
Abstract
In this study, we elucidated the mechanism by which human choline kinase-α (hCKα) interacts with nonstructural protein 5A (NS5A) and phosphatidylinositol-4-kinase IIIα (PI4KIIIα), the lipid kinase crucial for maintaining the integrity of virus-induced membranous webs, and modulates hepatitis C virus (HCV) replication. hCKα activity positively modulated phosphatidylinositol-4-phosphate (PI4P) levels in HCV-expressing cells, and hCKα-mediated PI4P accumulation was abolished by AL-9, a PI4KIIIα-specific inhibitor. hCKα colocalized with NS5A and PI4KIIIα or PI4P; NS5A expression increased hCKα and PI4KIIIα colocalization; and hCKα formed a ternary complex with PI4KIIIα and NS5A, supporting the functional interplay of hCKα with PI4KIIIα and NS5A. PI4KIIIα inactivation by AL-9 or hCKα inactivation by CK37, a specific hCKα inhibitor, impaired the endoplasmic reticulum (ER) localization and colocalization of these three molecules. Interestingly, hCKα knockdown or inactivation inhibited PI4KIIIα-NS5A binding. In an in vitro PI4KIIIα activity assay, hCKα activity slightly increased PI4KIIIα basal activity but greatly augmented NS5A-induced PI4KIIIα activity, supporting the essential role of ternary complex formation in robust PI4KIIIα activation. Concurring with the upregulation of PI4P production and viral replication, overexpression of active hCKα-R (but not the D288A mutant) restored PI4KIIIα and NS5A translocation to the ER in hCKα stable knockdown cells. Furthermore, active PI4KIIIα overexpression restored PI4P production, PI4KIIIα and NS5A translocation to the ER, and viral replication in CK37-treated cells. Based on our results, hCKα functions as an indispensable regulator that bridges PI4KIIIα and NS5A and potentiates NS5A-stimulated PI4KIIIα activity, which then facilitates the targeting of the ternary complex to the ER for viral replication. IMPORTANCE The mechanisms by which hCKα activity modulates the transport of the hCKα-NS5A complex to the ER are not understood. In the present study, we investigated how hCKα interacts with PI4KIIIα (a key element that maintains the integrity of the “membranous web” structure) and NS5A to regulate viral replication. We demonstrated that HCV hijacks hCKα to bridge PI4KIIIα and NS5A, forming a ternary complex, which then stimulates PI4KIIIα activity to produce PI4P. Pronounced PI4P synthesis then redirects the translocation of the ternary complex to the ER-derived, PI4P-enriched membrane for assembly of the viral replication complex and viral replication. Our study provides novel insights into the indispensable modulatory role of hCKα in the recruitment of PI4KIIIα to NS5A and in NS5A-stimulated PI4P production and reveals a new perspective for understanding the impact of profound PI4KIIIα activation on the targeting of PI4KIIIα and NS5A to the PI4P-enriched membrane for viral replication complex formation.
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Abstract
PURPOSE OF REVIEW Direct-acting antiviral agents (DAAs) have markedly improved the prognosis of hepatitis C virus (HCV)-genotype 3 (GT3), a highly prevalent infection worldwide. However, in patients with hepatic fibrosis, cirrhosis, or hepatocellular carcinoma (HCC), GT3 infection presents a treatment challenge compared with other genotypes. The dependence of the HCV life cycle on host lipid metabolism suggests the possible utility of targeting host cellular factors for combination anti-HCV therapy. We discuss current and emergent DAA regimens for HCV-GT3 treatment. We then summarize recent research findings on the reliance of HCV entry, replication, and virion assembly on host lipid metabolism. RECENT FINDINGS Current HCV treatment guidelines recommend the use of daclatasvir plus sofosbuvir (DCV/SOF) or sofosbuvir plus velpatasvir (SOF/VEL) for the management of GT3 based upon clinical efficacy [≥88% overall sustained virological response (SVR)] and tolerability. Potential future DAA options, such as SOF/VEL co-formulated with GS-9857, also look promising in treating cirrhotic GT3 patients. However, HCV resistance to DAAs will likely continue to impact the therapeutic efficacy of interferon-free treatment regimens. Disruption of HCV entry by targeting required host cellular receptors shows potential in minimizing HCV resistance and broadening therapeutic options for certain subpopulations of GT3 patients. The use of cholesterol biosynthesis and transport inhibitors may also improve health outcomes for GT3 patients when used synergistically with DAAs. Due to the morbidity and mortality associated with HCV-GT3 infection compared to other genotypes, efforts should be made to address current limitations in the therapeutic prevention and management of HCV-GT3 infection.
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46
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Altan-Bonnet N. Lipid Tales of Viral Replication and Transmission. Trends Cell Biol 2017; 27:201-213. [PMID: 27838086 PMCID: PMC5318230 DOI: 10.1016/j.tcb.2016.09.011] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Revised: 09/26/2016] [Accepted: 09/29/2016] [Indexed: 12/22/2022]
Abstract
Positive-strand RNA viruses are the largest group of RNA viruses on Earth and cellular membranes are critical for all aspects of their life cycle, from entry and replication to exit. In particular, membranes serve as platforms for replication and as carriers to transmit these viruses to other cells, the latter either as an envelope surrounding a single virus or as the vesicle containing a population of viruses. Notably, many animal and human viruses appear to induce and exploit phosphatidylinositol 4-phosphate/cholesterol-enriched membranes for replication, whereas many plant and insect-vectored animal viruses utilize phosphatidylethanolamine/cholesterol-enriched membranes for the same purpose; and phosphatidylserine-enriched membrane carriers are widely used by both single and populations of viruses for transmission. Here I discuss the implications for viral pathogenesis and therapeutic development of this remarkable convergence on specific membrane lipid blueprints for replication and transmission.
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Affiliation(s)
- Nihal Altan-Bonnet
- Laboratory of Host-Pathogen Dynamics, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
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47
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Strating JR, van Kuppeveld FJ. Viral rewiring of cellular lipid metabolism to create membranous replication compartments. Curr Opin Cell Biol 2017; 47:24-33. [PMID: 28242560 PMCID: PMC7127510 DOI: 10.1016/j.ceb.2017.02.005] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Revised: 02/02/2017] [Accepted: 02/09/2017] [Indexed: 02/08/2023]
Abstract
Positive-strand RNA (+RNA) viruses (e.g. poliovirus, hepatitis C virus, dengue virus, SARS-coronavirus) remodel cellular membranes to form so-called viral replication compartments (VRCs), which are the sites where viral RNA genome replication takes place. To induce VRC formation, these viruses extensively rewire lipid metabolism. Disparate viruses have many commonalities as well as disparities in their interactions with the host lipidome and accumulate specific sets of lipids (sterols, glycerophospholipids, sphingolipids) at their VRCs. Recent years have seen an upsurge in studies investigating the role of lipids in +RNA virus replication, in particular of sterols, and uncovered that membrane contact sites and lipid transfer proteins are hijacked by viruses and play pivotal roles in VRC formation.
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Affiliation(s)
- Jeroen Rpm Strating
- Utrecht University, Faculty of Veterinary Medicine, Department of Infectious Diseases & Immunology, Division of Virology, Utrecht, The Netherlands.
| | - Frank Jm van Kuppeveld
- Utrecht University, Faculty of Veterinary Medicine, Department of Infectious Diseases & Immunology, Division of Virology, Utrecht, The Netherlands.
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48
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Falcón V, Acosta-Rivero N, González S, Dueñas-Carrera S, Martinez-Donato G, Menéndez I, Garateix R, Silva JA, Acosta E, Kourı J. Ultrastructural and biochemical basis for hepatitis C virus morphogenesis. Virus Genes 2017; 53:151-164. [PMID: 28233195 DOI: 10.1007/s11262-017-1426-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 01/06/2017] [Indexed: 12/16/2022]
Abstract
Chronic infection with HCV is a leading cause of cirrhosis, hepatocellular carcinoma and liver failure. One of the least understood steps in the HCV life cycle is the morphogenesis of new viral particles. HCV infection alters the lipid metabolism and generates a variety of microenvironments in the cell cytoplasm that protect viral proteins and RNA promoting viral replication and assembly. Lipid droplets (LDs) have been proposed to link viral RNA synthesis and virion assembly by physically associating these viral processes. HCV assembly, envelopment, and maturation have been shown to take place at specialized detergent-resistant membranes in the ER, rich in cholesterol and sphingolipids, supporting the synthesis of luminal LDs-containing ApoE. HCV assembly involves a regulated allocation of viral and host factors to viral assembly sites. Then, virus budding takes place through encapsidation of the HCV genome and viral envelopment in the ER. Interaction of ApoE with envelope proteins supports the viral particle acquisition of lipids and maturation. HCV secretion has been suggested to entail the ion channel activity of viral p7, several components of the classical trafficking and autophagy pathways, ESCRT, and exosome-mediated export of viral RNA. Here, we review the most recent advances in virus morphogenesis and the interplay between viral and host factors required for the formation of HCV virions.
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Affiliation(s)
- Viviana Falcón
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba.
| | - Nelson Acosta-Rivero
- National Center for Scientific Research, P.O. Box 6414, 10600, Havana, Cuba. .,Centre for Protein Studies, Faculty of Biology, University of Havana, 10400, Havana, Cuba.
| | | | | | | | - Ivon Menéndez
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba
| | - Rocio Garateix
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba
| | - José A Silva
- Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, C.P. 10600, Havana, Cuba
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49
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Tuning a cellular lipid kinase activity adapts hepatitis C virus to replication in cell culture. Nat Microbiol 2016; 2:16247. [PMID: 27991882 DOI: 10.1038/nmicrobiol.2016.247] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 11/04/2016] [Indexed: 12/30/2022]
Abstract
With a single exception, all isolates of hepatitis C virus (HCV) require adaptive mutations to replicate efficiently in cell culture. Here, we show that a major class of adaptive mutations regulates the activity of a cellular lipid kinase, phosphatidylinositol 4-kinase IIIα (PI4KA). HCV needs to stimulate PI4KA to create a permissive phosphatidylinositol 4-phosphate-enriched membrane microenvironment in the liver and in primary human hepatocytes (PHHs). In contrast, in Huh7 hepatoma cells, the virus must acquire loss-of-function mutations that prevent PI4KA overactivation. This adaptive mechanism is necessitated by increased PI4KA levels in Huh7 cells compared with PHHs, and is conserved across HCV genotypes. PI4KA-specific inhibitors promote replication of unadapted viral isolates and allow efficient replication of patient-derived virus in cell culture. In summary, this study has uncovered a long-sought mechanism of HCV cell-culture adaptation and demonstrates how a virus can adapt to changes in a cellular environment associated with tumorigenesis.
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50
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Miyamura T, Lemon SM, Walker CM, Wakita T. The HCV Replicase Complex and Viral RNA Synthesis. HEPATITIS C VIRUS I 2016. [PMCID: PMC7122888 DOI: 10.1007/978-4-431-56098-2_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Replication of hepatitis C virus (HCV) is tightly linked to membrane alterations designated the membranous web, harboring the viral replicase complex. In this chapter we describe the morphology and 3D architecture of the HCV-induced replication organelles, mainly consisting of double membrane vesicles, which are generated by a concerted action of the nonstructural proteins NS3 to NS5B. Recent studies have furthermore identified a number of host cell proteins and lipids contributing to the biogenesis of the membranous web, which are discussed in this chapter. Viral RNA synthesis is tightly associated with these membrane alterations and mainly driven by the viral RNA dependent RNA polymerase NS5B. We summarize our current knowledge of the structure and function of NS5B, the role of cis-acting replication elements at the termini of the genome in regulating RNA synthesis and the contribution of additional viral and host factors to viral RNA synthesis, which is still ill defined.
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Affiliation(s)
- Tatsuo Miyamura
- National Institute of Infectious Diseases, Tokyo, Tokyo Japan
| | - Stanley M. Lemon
- Departments of Medicine and Microbiology & Immunology , The University of North Carolina, Chapel Hill, North Carolina USA
| | - Christopher M. Walker
- Center for Vaccines and Immunity, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio USA
| | - Takaji Wakita
- National Institute of Infectious Diseases, Tokyo, Tokyo Japan
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