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Chen L, Yang L, Li Y, Liu T, Yang B, Liu L, Wu R. Autophagy and Inflammation: Regulatory Roles in Viral Infections. Biomolecules 2023; 13:1454. [PMID: 37892135 PMCID: PMC10604974 DOI: 10.3390/biom13101454] [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: 08/25/2023] [Revised: 09/19/2023] [Accepted: 09/19/2023] [Indexed: 10/29/2023] Open
Abstract
Autophagy is a highly conserved intracellular degradation pathway in eukaryotic organisms, playing an adaptive role in various pathophysiological processes throughout evolution. Inflammation is the immune system's response to external stimuli and tissue damage. However, persistent inflammatory reactions can lead to a range of inflammatory diseases and cancers. The interaction between autophagy and inflammation is particularly evident during viral infections. As a crucial regulator of inflammation, autophagy can either promote or inhibit the occurrence of inflammatory responses. In turn, inflammation can establish negative feedback loops by modulating autophagy to suppress excessive inflammatory reactions. This interaction is pivotal in the pathogenesis of viral diseases. Therefore, elucidating the regulatory roles of autophagy and inflammation in viral infections will significantly enhance our understanding of the mechanisms underlying related diseases. Furthermore, it will provide new insights and theoretical foundations for disease prevention, treatment, and drug development.
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Affiliation(s)
- Li Chen
- School of Medicine, Jiamusi University, Jiamusi 154007, China; (L.C.); (Y.L.); (T.L.); (B.Y.)
| | - Limin Yang
- School of Medicine, Dalian University, Dalian 116622, China;
| | - Yingyu Li
- School of Medicine, Jiamusi University, Jiamusi 154007, China; (L.C.); (Y.L.); (T.L.); (B.Y.)
| | - Tianrun Liu
- School of Medicine, Jiamusi University, Jiamusi 154007, China; (L.C.); (Y.L.); (T.L.); (B.Y.)
| | - Bolun Yang
- School of Medicine, Jiamusi University, Jiamusi 154007, China; (L.C.); (Y.L.); (T.L.); (B.Y.)
| | - Lei Liu
- School of Medicine, Jiamusi University, Jiamusi 154007, China; (L.C.); (Y.L.); (T.L.); (B.Y.)
| | - Rui Wu
- School of Medicine, Jiamusi University, Jiamusi 154007, China; (L.C.); (Y.L.); (T.L.); (B.Y.)
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2
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Breitinger U, Farag NS, Sticht H, Breitinger HG. Viroporins: Structure, function, and their role in the life cycle of SARS-CoV-2. Int J Biochem Cell Biol 2022; 145:106185. [PMID: 35219876 PMCID: PMC8868010 DOI: 10.1016/j.biocel.2022.106185] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/15/2022] [Accepted: 02/21/2022] [Indexed: 12/12/2022]
Abstract
Viroporins are indispensable for viral replication. As intracellular ion channels they disturb pH gradients of organelles and allow Ca2+ flux across ER membranes. Viroporins interact with numerous intracellular proteins and pathways and can trigger inflammatory responses. Thus, they are relevant targets in the search for antiviral drugs. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) underlies the world-wide pandemic of COVID-19, where an effective therapy is still lacking despite impressive progress in the development of vaccines and vaccination campaigns. Among the 29 proteins of SARS-CoV-2, the E- and ORF3a proteins have been identified as viroporins that contribute to the massive release of inflammatory cytokines observed in COVID-19. Here, we describe structure and function of viroporins and their role in inflammasome activation and cellular processes during the virus replication cycle. Techniques to study viroporin function are presented, with a focus on cellular and electrophysiological assays. Contributions of SARS-CoV-2 viroporins to the viral life cycle are discussed with respect to their structure, channel function, binding partners, and their role in viral infection and virus replication. Viroporin sequences of new variants of concern (α–ο) of SARS-CoV-2 are briefly reviewed as they harbour changes in E and 3a proteins that may affect their function.
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Affiliation(s)
- Ulrike Breitinger
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Noha S Farag
- Department of Microbiology and Immunology, German University in Cairo, New Cairo, Egypt
| | - Heinrich Sticht
- Division of Bioinformatics, Institute for Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
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3
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The Interplay between Autophagy and Virus Pathogenesis—The Significance of Autophagy in Viral Hepatitis and Viral Hemorrhagic Fevers. Cells 2022; 11:cells11050871. [PMID: 35269494 PMCID: PMC8909602 DOI: 10.3390/cells11050871] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 02/23/2022] [Accepted: 02/28/2022] [Indexed: 12/17/2022] Open
Abstract
Autophagy is a process focused on maintaining the homeostasis of organisms; nevertheless, the role of this process has also been widely documented in viral infections. Thus, xenophagy is a selective form of autophagy targeting viruses. However, the relation between autophagy and viruses is ambiguous—this process may be used as a strategy to fight with a virus, but is also in favor of the virus’s replication. In this paper, we have gathered data on autophagy in viral hepatitis and viral hemorrhagic fevers and the relations impacting its viral pathogenesis. Thus, autophagy is a potential therapeutic target, but research is needed to fully understand the mechanisms by which the virus interacts with the autophagic machinery. These studies must be performed in specific research models other than the natural host for many reasons. In this paper, we also indicate Lagovirus europaeus virus as a potentially good research model for acute liver failure and viral hemorrhagic disease.
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4
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Qian H, Chao X, Williams J, Fulte S, Li T, Yang L, Ding WX. Autophagy in liver diseases: A review. Mol Aspects Med 2021; 82:100973. [PMID: 34120768 DOI: 10.1016/j.mam.2021.100973] [Citation(s) in RCA: 137] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/29/2021] [Accepted: 05/30/2021] [Indexed: 02/07/2023]
Abstract
The liver is a highly dynamic metabolic organ that plays critical roles in plasma protein synthesis, gluconeogenesis and glycogen storage, cholesterol metabolism and bile acid synthesis as well as drug/xenobiotic metabolism and detoxification. Research from the past decades indicate that autophagy, the cellular catabolic process mediated by lysosomes, plays an important role in maintaining cellular and metabolic homeostasis in the liver. Hepatic autophagy fluctuates with hormonal cues and the availability of nutrients that respond to fed and fasting states as well as circadian activities. Dysfunction of autophagy in liver parenchymal and non-parenchymal cells can lead to various liver diseases including non-alcoholic fatty liver diseases, alcohol associated liver disease, drug-induced liver injury, cholestasis, viral hepatitis and hepatocellular carcinoma. Therefore, targeting autophagy may be a potential strategy for treating these various liver diseases. In this review, we will discuss the current progress on the understanding of autophagy in liver physiology. We will also discuss several forms of selective autophagy in the liver and the molecular signaling pathways in regulating autophagy of different cell types and their implications in various liver diseases.
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Affiliation(s)
- Hui Qian
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
| | - Xiaojuan Chao
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
| | - Jessica Williams
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
| | - Sam Fulte
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA
| | - Tiangang Li
- Harold Hamm Diabetes Center, Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - Ling Yang
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, Pappajohn Biomedical Institute, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, KS, 66160, USA.
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Brimson JM, Prasanth MI, Malar DS, Brimson S, Thitilertdecha P, Tencomnao T. Drugs that offer the potential to reduce hospitalization and mortality from SARS-CoV-2 infection: The possible role of the sigma-1 receptor and autophagy. Expert Opin Ther Targets 2021; 25:435-449. [PMID: 34236922 PMCID: PMC8290373 DOI: 10.1080/14728222.2021.1952987] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 02/07/2023]
Abstract
Introduction: Despite the availability of new vaccines for SARS-CoV-2, there has been slow uptake and problems with supply in some parts of the world. Hence, there is still a necessity for drugs that can prevent hospitalization of patients and reduce the strain on health care systems. Drugs with sigma affinity potentially provide protection against the most severe symptoms of SARS-COV-2 and could prevent mortality via interactions with the sigma-1 receptor.Areas covered: This review examines the role of the sigma-1 receptor and autophagy in SARS-CoV-2 infections and how they may be linked. The authors reveal how sigma ligands may reduce the symptoms, complications, and deaths resulting from SARS-CoV-2 and offer insights on those patient cohorts that may benefit most from these drugs.Expert opinion: Drugs with sigma affinity potentially offer protection against the most severe symptoms of SARS-CoV-2 via interactions with the sigma-1 receptor. Agonists of the sigma-1 receptor may provide protection of the mitochondria, activate mitophagy to remove damaged and leaking mitochondria, prevent ER stress, manage calcium ion transport, and induce autophagy to prevent cell death in response to infection.
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Affiliation(s)
- James Michael Brimson
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Mani Iyer Prasanth
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Dicson Sheeja Malar
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Sirikalaya Brimson
- Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Premrutai Thitilertdecha
- Siriraj Research Group in Immunobiology and Therapeutic Sciences, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Tewin Tencomnao
- Natural Products for Neuroprotection and Anti-ageing Research Unit, Chulalongkorn University, Bangkok, Thailand
- Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
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6
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Kouroumalis E, Voumvouraki A, Augoustaki A, Samonakis DN. Autophagy in liver diseases. World J Hepatol 2021; 13:6-65. [PMID: 33584986 PMCID: PMC7856864 DOI: 10.4254/wjh.v13.i1.6] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 12/10/2020] [Accepted: 12/26/2020] [Indexed: 02/06/2023] Open
Abstract
Autophagy is the liver cell energy recycling system regulating a variety of homeostatic mechanisms. Damaged organelles, lipids and proteins are degraded in the lysosomes and their elements are re-used by the cell. Investigations on autophagy have led to the award of two Nobel Prizes and a health of important reports. In this review we describe the fundamental functions of autophagy in the liver including new data on the regulation of autophagy. Moreover we emphasize the fact that autophagy acts like a two edge sword in many occasions with the most prominent paradigm being its involvement in the initiation and progress of hepatocellular carcinoma. We also focused to the implication of autophagy and its specialized forms of lipophagy and mitophagy in the pathogenesis of various liver diseases. We analyzed autophagy not only in well studied diseases, like alcoholic and nonalcoholic fatty liver and liver fibrosis but also in viral hepatitis, biliary diseases, autoimmune hepatitis and rare diseases including inherited metabolic diseases and also acetaminophene hepatotoxicity. We also stressed the different consequences that activation or impairment of autophagy may have in hepatocytes as opposed to Kupffer cells, sinusoidal endothelial cells or hepatic stellate cells. Finally, we analyzed the limited clinical data compared to the extensive experimental evidence and the possible future therapeutic interventions based on autophagy manipulation.
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Affiliation(s)
- Elias Kouroumalis
- Liver Research Laboratory, University of Crete Medical School, Heraklion 71110, Greece
| | - Argryro Voumvouraki
- 1 Department of Internal Medicine, AHEPA University Hospital, Thessaloniki 54636, Greece
| | - Aikaterini Augoustaki
- Department of Gastroenterology and Hepatology, University Hospital of Crete, Heraklion 71110, Greece
| | - Dimitrios N Samonakis
- Department of Gastroenterology and Hepatology, University Hospital of Crete, Heraklion 71110, Greece.
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7
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Chu JYK, Ou JHJ. Autophagy in HCV Replication and Protein Trafficking. Int J Mol Sci 2021; 22:ijms22031089. [PMID: 33499186 PMCID: PMC7865906 DOI: 10.3390/ijms22031089] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/19/2021] [Accepted: 01/21/2021] [Indexed: 12/11/2022] Open
Abstract
Autophagy is a catabolic process that is important for maintaining cellular homeostasis. It is also known to possess other functions including protein trafficking and anti-microbial activities. Hepatitis C virus (HCV) is known to co-opt cellular autophagy pathway to promote its own replication. HCV regulates autophagy through multiple mechanisms to control intracellular protein and membrane trafficking to enhance its replication and suppress host innate immune response. In this review, we discuss the current knowledge on the interplay between HCV and autophagy and the crosstalk between HCV-induced autophagy and host innate immune responses.
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Kim D, Hwang HY, Kwon HJ. Targeting Autophagy In Disease: Recent Advances In Drug Discovery. Expert Opin Drug Discov 2020; 15:1045-1064. [DOI: 10.1080/17460441.2020.1773429] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Dasol Kim
- Chemical Genomics Global Research Laboratory, Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Hui-Yun Hwang
- Chemical Genomics Global Research Laboratory, Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Ho Jeong Kwon
- Chemical Genomics Global Research Laboratory, Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
- Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
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9
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Vescovo T, Pagni B, Piacentini M, Fimia GM, Antonioli M. Regulation of Autophagy in Cells Infected With Oncogenic Human Viruses and Its Impact on Cancer Development. Front Cell Dev Biol 2020; 8:47. [PMID: 32181249 PMCID: PMC7059124 DOI: 10.3389/fcell.2020.00047] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/20/2020] [Indexed: 12/14/2022] Open
Abstract
About 20% of total cancer cases are associated to infections. To date, seven human viruses have been directly linked to cancer development: high-risk human papillomaviruses (hrHPVs), Merkel cell polyomavirus (MCPyV), hepatitis B virus (HBV), hepatitis C virus (HCV), Epstein–Barr virus (EBV), Kaposi’s sarcoma-associated herpesvirus (KSHV), and human T-lymphotropic virus 1 (HTLV-1). These viruses impact on several molecular mechanisms in the host cells, often resulting in chronic inflammation, uncontrolled proliferation, and cell death inhibition, and mechanisms, which favor viral life cycle but may indirectly promote tumorigenesis. Recently, the ability of oncogenic viruses to alter autophagy, a catabolic process activated during the innate immune response to infections, is emerging as a key event for the onset of human cancers. Here, we summarize the current understanding of the molecular mechanisms by which human oncogenic viruses regulate autophagy and how this negative regulation impacts on cancer development. Finally, we highlight novel autophagy-related candidates for the treatment of virus-related cancers.
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Affiliation(s)
- Tiziana Vescovo
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy
| | - Benedetta Pagni
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy.,Department of Biology, University of Rome "Tor Vergata," Rome, Italy
| | - Mauro Piacentini
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy.,Department of Biology, University of Rome "Tor Vergata," Rome, Italy
| | - Gian Maria Fimia
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy.,Department of Molecular Medicine, University of Rome "Sapienza," Rome, Italy
| | - Manuela Antonioli
- National Institute for Infectious Diseases "Lazzaro Spallanzani" - IRCCS, Rome, Italy
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10
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Hazari Y, Bravo-San Pedro JM, Hetz C, Galluzzi L, Kroemer G. Autophagy in hepatic adaptation to stress. J Hepatol 2020; 72:183-196. [PMID: 31849347 DOI: 10.1016/j.jhep.2019.08.026] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/13/2019] [Accepted: 08/28/2019] [Indexed: 02/06/2023]
Abstract
Autophagy is an evolutionarily ancient process whereby eukaryotic cells eliminate disposable or potentially dangerous cytoplasmic material, to support bioenergetic metabolism and adapt to stress. Accumulating evidence indicates that autophagy operates as a critical quality control mechanism for the maintenance of hepatic homeostasis in both parenchymal (hepatocytes) and non-parenchymal (stellate cells, sinusoidal endothelial cells, Kupffer cells) compartments. In line with this notion, insufficient autophagy has been aetiologically involved in the pathogenesis of multiple liver disorders, including alpha-1-antitrypsin deficiency, Wilson disease, non-alcoholic steatohepatitis, liver fibrosis and hepatocellular carcinoma. Here, we critically discuss the importance of functional autophagy for hepatic physiology, as well as the mechanisms whereby defects in autophagy cause liver disease.
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Affiliation(s)
- Younis Hazari
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago, Chile; FONDAP Center for Geroscience (GERO), Brain Health and Metabolism, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - José Manuel Bravo-San Pedro
- Equipe labellisée par la Ligue contre le cancer, Université de Paris, Sorbonne Université, INSERM U1138, Centre de Recherche des Cordeliers, Paris, France
| | - Claudio Hetz
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago, Chile; FONDAP Center for Geroscience (GERO), Brain Health and Metabolism, Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Buck Institute for Research in Aging, Novato, CA, USA.
| | - Lorenzo Galluzzi
- Department of Radiation Oncology, Weill Cornell Medical College, New York, NY, USA; Sandra and Edward Meyer Cancer Center, New York, NY, USA; Department of Dermatology, Yale School of Medicine, New Haven, CT, USA; Université Paris Descartes/Paris V, Paris, France
| | - Guido Kroemer
- Equipe labellisée par la Ligue contre le cancer, Université de Paris, Sorbonne Université, INSERM U1138, Centre de Recherche des Cordeliers, Paris, France; Université Paris Descartes/Paris V, Paris, France; Metabolomics and Cell Biology Platforms, Gustave Roussy Comprehensive Cancer Institute, Villejuif, France; Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France; Suzhou Institute for Systems Medicine, Chinese Academy of Sciences, Suzhou, China; Department of Women's and Children's Health, Karolinska University Hospital, Stockholm, Sweden.
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11
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Abstract
Autophagy plays an important role in the fight against viral infection, which can directly remove the virus, interact with the viral protein, and at the same time regulate the innate and adaptive immunity and promote virus clearance. The virus has also evolved autophagy, which evades, antagonizes and utilizes autophagy, and regulates autophagy pathways, affects autophagy maturation, changes autophagy small body environment or changes the body's immune response type to promote or inhibit autophagy. This chapter introduces the possible mechanisms of autophagy during pathogen infection such as human immunodeficiency virus and hepatitis virus, in order to provide new methods for the prevention and treatment of viral infection.
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Affiliation(s)
- Yichuan Xiao
- Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
| | - Wei Cai
- Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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12
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Hepatitis C Virus NS5A Protein Promotes the Lysosomal Degradation of Hepatocyte Nuclear Factor 1α via Chaperone-Mediated Autophagy. J Virol 2018; 92:JVI.00639-18. [PMID: 29695419 DOI: 10.1128/jvi.00639-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 04/17/2018] [Indexed: 12/31/2022] Open
Abstract
Hepatitis C virus (HCV) infection is closely associated with type 2 diabetes. We reported that HCV infection induces the lysosomal degradation of hepatocyte nuclear factor 1 alpha (HNF-1α) via interaction with HCV nonstructural protein 5A (NS5A) protein, thereby suppressing GLUT2 gene expression. The molecular mechanisms of selective degradation of HNF-1α caused by NS5A are largely unknown. Chaperone-mediated autophagy (CMA) is a selective lysosomal degradation pathway. Here, we investigated whether CMA is involved in the selective degradation of HNF-1α in HCV-infected cells and observed that the pentapeptide spanning from amino acid (aa) 130 to aa 134 of HNF-1α matches the rule for the CMA-targeting motif, also known as KFERQ motif. A cytosolic chaperone protein, heat shock cognate protein of 70 kDa (HSC70), and a lysosomal membrane protein, lysosome-associated membrane protein type 2A (LAMP-2A), are key components of CMA. Immunoprecipitation analysis revealed that HNF-1α was coimmunoprecipitated with HSC70, whereas the Q130A mutation (mutation of Q to A at position 130) of HNF-1α disrupted the interaction with HSC70, indicating that the CMA-targeting motif of HNF-1α is important for the association with HSC70. Immunoprecipitation analysis revealed that increasing amounts of NS5A enhanced the association of HNF-1α with HSC70. To determine whether LAMP-2A plays a role in the degradation of HNF-1α protein, we knocked down LAMP-2A mRNA by RNA interference; this knockdown by small interfering RNA (siRNA) recovered the level of HNF-1α protein in HCV J6/JFH1-infected cells. This result suggests that LAMP-2A is required for the degradation of HNF-1α. Immunofluorescence study revealed colocalization of NS5A and HNF-1α in the lysosome. Based on our findings, we propose that HCV NS5A interacts with HSC70 and recruits HSC70 to HNF-1α, thereby promoting the lysosomal degradation of HNF-1α via CMA.IMPORTANCE Many viruses use a protein degradation system, such as the ubiquitin-proteasome pathway or the autophagy pathway, for facilitating viral propagation and viral pathogenesis. We investigated the mechanistic details of the selective lysosomal degradation of hepatocyte nuclear factor 1 alpha (HNF-1α) induced by hepatitis C virus (HCV) NS5A protein. Using site-directed mutagenesis, we demonstrated that HNF-1α contains a pentapeptide chaperone-mediated autophagy (CMA)-targeting motif within the POU-specific domain of HNF-1α. The CMA-targeting motif is important for the association with HSC70. LAMP-2A is required for degradation of HNF-1α caused by NS5A. We propose that HCV NS5A interacts with HSC70, a key component of the CMA machinery, and recruits HSC70 to HNF-1α to target HNF-1α for CMA-mediated lysosomal degradation, thereby facilitating HCV pathogenesis. We discovered a role of HCV NS5A in CMA-dependent degradation of HNF-1α. Our results may lead to a better understanding of the role of CMA in the pathogenesis of HCV.
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Shrivastava G, García-Cordero J, León-Juárez M, Oza G, Tapia-Ramírez J, Villegas-Sepulveda N, Cedillo-Barrón L. NS2A comprises a putative viroporin of Dengue virus 2. Virulence 2017; 8:1450-1456. [PMID: 28723277 PMCID: PMC5711424 DOI: 10.1080/21505594.2017.1356540] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 06/30/2017] [Accepted: 06/30/2017] [Indexed: 12/31/2022] Open
Affiliation(s)
- Gaurav Shrivastava
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV-IPN), México City, México
| | - Julio García-Cordero
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV-IPN), México City, México
| | - Moisés León-Juárez
- Department of Immunobiochemistry, National Institute of Perinatology, México City, México
| | - Goldie Oza
- Department of Genetics and Molecular Biology, Center for Research and Advanced Studies (CINVESTAV-IPN), México City, México
| | - Jose Tapia-Ramírez
- Department of Genetics and Molecular Biology, Center for Research and Advanced Studies (CINVESTAV-IPN), México City, México
| | - Nicolas Villegas-Sepulveda
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV-IPN), México City, México
| | - Leticia Cedillo-Barrón
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV-IPN), México City, México
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14
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Hepatitis C Virus-Induced Autophagy and Host Innate Immune Response. Viruses 2017; 9:v9080224. [PMID: 28805674 PMCID: PMC5580481 DOI: 10.3390/v9080224] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 08/04/2017] [Accepted: 08/11/2017] [Indexed: 02/07/2023] Open
Abstract
Autophagy is a catabolic process that is important for maintaining cellular homeostasis. This pathway in hepatocytes is stimulated and controlled by the hepatitis C virus (HCV)—upon infection—to promote its own replication. HCV induces autophagy indirectly and directly through different mechanisms and temporally controls the autophagic flux. This enables the virus to maximize its replication and attenuate the innate immune responses that it activates. In this review, we discuss the relationship between HCV and autophagy, and the crosstalk between HCV-induced autophagy and host innate immune responses.
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15
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Abstract
Autophagy is a catabolic process by which cells remove protein aggregates and damaged organelles for recycling. It can also be used by cells to remove intracellular microbial pathogens, including viruses, in a process known as xenophagy. However, many viruses have developed mechanisms to subvert this intracellular antiviral response and even use this pathway to support their own replications. Hepatitis C virus (HCV) is one such virus and is an important human pathogen that can cause severe liver diseases. Recent studies indicated that HCV could activate the autophagic pathway to support its replication. This review summarizes the current knowledge on the interplay between HCV and autophagy and how this interplay affects HCV replication and host innate immune responses.
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16
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Pujhari S, Zakhartchouk AN. Porcine reproductive and respiratory syndrome virus envelope (E) protein interacts with mitochondrial proteins and induces apoptosis. Arch Virol 2016; 161:1821-30. [DOI: 10.1007/s00705-016-2845-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/26/2016] [Indexed: 12/15/2022]
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León-Juárez M, Martínez-Castillo M, Shrivastava G, García-Cordero J, Villegas-Sepulveda N, Mondragón-Castelán M, Mondragón-Flores R, Cedillo-Barrón L. Recombinant Dengue virus protein NS2B alters membrane permeability in different membrane models. Virol J 2016; 13:1. [PMID: 26728778 PMCID: PMC4700614 DOI: 10.1186/s12985-015-0456-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 12/21/2015] [Indexed: 11/18/2022] Open
Abstract
Background One of the main phenomena occurring in cellular membranes during virus infection is a change in membrane permeability. It has been observed that numerous viral proteins can oligomerize and form structures known as viroporins that alter the permeability of membranes. Previous findings have identified such proteins in cells infected with Japanese encephalitis virus (JEV), a member of the same family that Dengue virus (DENV) belongs to (Flaviviridae). In the present work, we investigated whether the small hydrophobic DENV protein NS2B serves a viroporin function. Methods We cloned the DENV NS2B sequence and expressed it in a bacterial expression system. Subsequently, we evaluated the effect of DENV NS2B on membranes when NS2B was overexpressed, measured bacterial growth restriction, and evaluated changes of permeability to hygromycin. The NS2B protein was purified by affinity chromatography, and crosslinking assays were performed to determine the presence of oligomers. Hemolysis assays and transmission electron microscopy were performed to identify structures involved in permeability changes. Results The DENV-2 NS2B protein showed similitude with the JEV viroporin. The DENV-2 NS2B protein possessed the ability to change the membrane permeability in bacteria, to restrict bacterial cell growth, and to enable membrane permeability to hygromycin B. The NS2B protein formed trimers that could participate in cell lysis and generate organized structures on eukaryotes membranes. Conclusions Our data suggest that the DENV-2 NS2B viral protein is capable of oligomerizing and organizing to form pore-like structures in different lipid environments, thereby modifying the permeability of cell membranes.
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Affiliation(s)
- Moisés León-Juárez
- Departmento de Biomedicina Molecular, Centro de Investigacion y Estudios avanzados IPN, Av. Instituto Politecnico 2508 Col. San Pedro Zacatenco, 07360, México, Mexico. .,Present Address: Departamento de Inmunobioquimica, Instituto Nacional de Perinatología, Montes Urales #800 Col. Lomas de Virreyes, 1100, México, Mexico.
| | - Macario Martínez-Castillo
- Departmento de Biomedicina Molecular, Centro de Investigacion y Estudios avanzados IPN, Av. Instituto Politecnico 2508 Col. San Pedro Zacatenco, 07360, México, Mexico.
| | - Gaurav Shrivastava
- Departmento de Biomedicina Molecular, Centro de Investigacion y Estudios avanzados IPN, Av. Instituto Politecnico 2508 Col. San Pedro Zacatenco, 07360, México, Mexico.
| | - Julio García-Cordero
- Departmento de Biomedicina Molecular, Centro de Investigacion y Estudios avanzados IPN, Av. Instituto Politecnico 2508 Col. San Pedro Zacatenco, 07360, México, Mexico.
| | - Nicolás Villegas-Sepulveda
- Departmento de Biomedicina Molecular, Centro de Investigacion y Estudios avanzados IPN, Av. Instituto Politecnico 2508 Col. San Pedro Zacatenco, 07360, México, Mexico.
| | - Mónica Mondragón-Castelán
- Departamento de Bioquímica, CINVESTAV IPN Av, IPN # 2508 Col. San Pedro Zacatenco, 07360, México, DF, Mexico.
| | - Ricardo Mondragón-Flores
- Departamento de Bioquímica, CINVESTAV IPN Av, IPN # 2508 Col. San Pedro Zacatenco, 07360, México, DF, Mexico.
| | - Leticia Cedillo-Barrón
- Departmento de Biomedicina Molecular, Centro de Investigacion y Estudios avanzados IPN, Av. Instituto Politecnico 2508 Col. San Pedro Zacatenco, 07360, México, Mexico.
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18
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Barnwal B, Karlberg H, Mirazimi A, Tan YJ. The Non-structural Protein of Crimean-Congo Hemorrhagic Fever Virus Disrupts the Mitochondrial Membrane Potential and Induces Apoptosis. J Biol Chem 2015; 291:582-92. [PMID: 26574543 DOI: 10.1074/jbc.m115.667436] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Indexed: 11/06/2022] Open
Abstract
Viruses have developed distinct strategies to overcome the host defense system. Regulation of apoptosis in response to viral infection is important for virus survival and dissemination. Like other viruses, Crimean-Congo hemorrhagic fever virus (CCHFV) is known to regulate apoptosis. This study, for the first time, suggests that the non-structural protein NSs of CCHFV, a member of the genus Nairovirus, induces apoptosis. In this report, we demonstrated the expression of CCHFV NSs, which contains 150 amino acid residues, in CCHFV-infected cells. CCHFV NSs undergoes active degradation during infection. We further demonstrated that ectopic expression of CCHFV NSs induces apoptosis, as reflected by caspase-3/7 activity and cleaved poly(ADP-ribose) polymerase, in different cell lines that support CCHFV replication. Using specific inhibitors, we showed that CCHFV NSs induces apoptosis via both intrinsic and extrinsic pathways. The minimal active region of the CCHFV NSs protein was determined to be 93-140 amino acid residues. Using alanine scanning, we demonstrated that Leu-127 and Leu-135 are the key residues for NSs-induced apoptosis. Interestingly, CCHFV NSs co-localizes in mitochondria and also disrupts the mitochondrial membrane potential. We also demonstrated that Leu-127 and Leu-135 are important residues for disruption of the mitochondrial membrane potential by NSs. Therefore, these results indicate that the C terminus of CCHFV NSs triggers mitochondrial membrane permeabilization, leading to activation of caspases, which, ultimately, leads to apoptosis. Given that multiple factors contribute to apoptosis during CCHFV infection, further studies are needed to define the involvement of CCHFV NSs in regulating apoptosis in infected cells.
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Affiliation(s)
- Bhaskar Barnwal
- From the Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, the Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research, Singapore
| | | | - Ali Mirazimi
- the Public Health Agency of Sweden, 17182 Solna, Sweden, the Karolinska Institute, 17177 Stockholm, Sweden, and the National Veterinary Institute, 75651 Uppsala, Sweden
| | - Yee-Joo Tan
- From the Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, the Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research, Singapore,
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Viral Membrane Channels: Role and Function in the Virus Life Cycle. Viruses 2015; 7:3261-84. [PMID: 26110585 PMCID: PMC4488738 DOI: 10.3390/v7062771] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Revised: 05/20/2015] [Accepted: 06/12/2015] [Indexed: 12/23/2022] Open
Abstract
Viroporins are small, hydrophobic trans-membrane viral proteins that oligomerize to form hydrophilic pores in the host cell membranes. These proteins are crucial for the pathogenicity and replication of viruses as they aid in various stages of the viral life cycle, from genome uncoating to viral release. In addition, the ion channel activity of viroporin causes disruption in the cellular ion homeostasis, in particular the calcium ion. Fluctuation in the calcium level triggers the activation of the host defensive programmed cell death pathways as well as the inflammasome, which in turn are being subverted for the viruses’ replication benefits. This review article summarizes recent developments in the functional investigation of viroporins from various viruses and their contributions to viral replication and virulence.
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20
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Scott C, Griffin S. Viroporins: structure, function and potential as antiviral targets. J Gen Virol 2015; 96:2000-2027. [PMID: 26023149 DOI: 10.1099/vir.0.000201] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The channel-forming activity of a family of small, hydrophobic integral membrane proteins termed 'viroporins' is essential to the life cycles of an increasingly diverse range of RNA and DNA viruses, generating significant interest in targeting these proteins for antiviral development. Viroporins vary greatly in terms of their atomic structure and can perform multiple functions during the virus life cycle, including those distinct from their role as oligomeric membrane channels. Recent progress has seen an explosion in both the identification and understanding of many such proteins encoded by highly significant pathogens, yet the prototypic M2 proton channel of influenza A virus remains the only example of a viroporin with provenance as an antiviral drug target. This review attempts to summarize our current understanding of the channel-forming functions for key members of this growing family, including recent progress in structural studies and drug discovery research, as well as novel insights into the life cycles of many viruses revealed by a requirement for viroporin activity. Ultimately, given the successes of drugs targeting ion channels in other areas of medicine, unlocking the therapeutic potential of viroporins represents a valuable goal for many of the most significant viral challenges to human and animal health.
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Affiliation(s)
- Claire Scott
- Leeds Institute of Cancer & Pathology and Leeds CRUK Clinical Centre, Faculty of Medicine and Health, St James's University Hospital, University of Leeds, Beckett Street, Leeds LS9 7TF, UK
| | - Stephen Griffin
- Leeds Institute of Cancer & Pathology and Leeds CRUK Clinical Centre, Faculty of Medicine and Health, St James's University Hospital, University of Leeds, Beckett Street, Leeds LS9 7TF, UK
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21
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Aweya JJ, Sze CW, Bayega A, Mohd-Ismail NK, Deng L, Hotta H, Tan YJ. NS5B induces up-regulation of the BH3-only protein, BIK, essential for the hepatitis C virus RNA replication and viral release. Virology 2014; 474:41-51. [PMID: 25463603 PMCID: PMC7127593 DOI: 10.1016/j.virol.2014.10.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 10/24/2014] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) induces cytopathic effects in the form of hepatocytes apoptosis thought to be resulted from the interaction between viral proteins and host factors. Using pathway specific PCR array, we identified 9 apoptosis-related genes that are dysregulated during HCV infection, of which the BH3-only pro-apoptotic Bcl-2 family protein, BIK, was consistently up-regulated at the mRNA and protein levels. Depletion of BIK protected host cells from HCV-induced caspase-3/7 activation but not the inhibitory effect of HCV on cell viability. Furthermore, viral RNA replication and release were significantly suppressed in BIK-depleted cells and over-expression of the RNA-dependent RNA polymerase, NS5B, was able to induce BIK expression. Immunofluorescence and co-immunoprecipitation assays showed co-localization and interaction of BIK and NS5B, suggesting that BIK may be interacting with the HCV replication complex through NS5B. These results imply that BIK is essential for HCV replication and that NS5B is able to induce BIK expression.
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Affiliation(s)
- Jude Juventus Aweya
- Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System (NUHS), National University of Singapore, Singapore
| | - Ching Wooen Sze
- Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System (NUHS), National University of Singapore, Singapore
| | - Anthony Bayega
- Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System (NUHS), National University of Singapore, Singapore; Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A⁎STAR), Singapore 138673, Singapore
| | - Nur Khairiah Mohd-Ismail
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A⁎STAR), Singapore 138673, Singapore
| | - Lin Deng
- Division of Microbiology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Hak Hotta
- Division of Microbiology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Yee-Joo Tan
- Department of Microbiology, Yong Loo Lin School of Medicine, National University Health System (NUHS), National University of Singapore, Singapore; Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A⁎STAR), Singapore 138673, Singapore.
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22
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Autophagy in HCV infection: keeping fat and inflammation at bay. BIOMED RESEARCH INTERNATIONAL 2014; 2014:265353. [PMID: 25162004 PMCID: PMC4138948 DOI: 10.1155/2014/265353] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 07/11/2014] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) infection is one of the main causes of chronic liver disease. Viral persistence and pathogenesis rely mainly on the ability of HCV to deregulate specific host processes, including lipid metabolism and innate immunity. Recently, autophagy has emerged as a cellular pathway, playing a role in several aspects of HCV infection. This review summarizes current knowledge on the molecular mechanisms that link the HCV life cycle with autophagy machinery. In particular, we discuss the role of HCV/autophagy interaction in dysregulating inflammation and lipid homeostasis and its potential for translational applications in the treatment of HCV-infected patients.
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23
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Atoom AM, Taylor NGA, Russell RS. The elusive function of the hepatitis C virus p7 protein. Virology 2014; 462-463:377-87. [PMID: 25001174 PMCID: PMC7112009 DOI: 10.1016/j.virol.2014.04.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 04/07/2014] [Accepted: 04/11/2014] [Indexed: 12/12/2022]
Abstract
Hepatitis C virus (HCV) is a major global health burden with 2–3% of the world׳s population being chronically infected. Persistent infection can lead to cirrhosis and hepatocellular carcinoma. Recently available treatment options show enhanced efficacy of virus clearance, but are associated with resistance and significant side effects. This warrants further research into the basic understanding of viral proteins and their pathophysiology. The p7 protein of HCV is an integral membrane protein that forms an ion-channel. The role of p7 in the HCV life cycle is presently uncertain, but most of the research performed to date highlights its role in the virus assembly process. The aim of this review is to provide an overview of the literature investigating p7, its structural and functional details, and to summarize the developments to date regarding potential anti-p7 compounds. A better understanding of this protein may lead to development of a new and effective therapy. This review paper provides an overview of the literature investigating HCV. The content focuses on p7 structural and functional details. We summarize the developments to date regarding potential anti-p7 compounds.
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Affiliation(s)
- Ali M Atoom
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University, Newfoundland, St. John׳s, Canada
| | - Nathan G A Taylor
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University, Newfoundland, St. John׳s, Canada
| | - Rodney S Russell
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University, Newfoundland, St. John׳s, Canada.
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24
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Datan E, Shirazian A, Benjamin S, Matassov D, Tinari A, Malorni W, Lockshin RA, Garcia-Sastre A, Zakeri Z. mTOR/p70S6K signaling distinguishes routine, maintenance-level autophagy from autophagic cell death during influenza A infection. Virology 2014; 452-453:175-190. [PMID: 24606695 DOI: 10.1016/j.virol.2014.01.008] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 11/22/2013] [Accepted: 01/13/2014] [Indexed: 12/17/2022]
Abstract
Autophagy, a stress response activated in influenza A virus infection helps the cell avoid apoptosis. However, in the absence of apoptosis infected cells undergo vastly expanded autophagy and nevertheless die in the presence of necrostatin but not of autophagy inhibitors. Combinations of inhibitors indicate that the controls of protective and lethal autophagy are different. Infection that triggers apoptosis also triggers canonical autophagy signaling exhibiting transient PI3K and mTORC1 activity. In terminal autophagy phospho-mTOR(Ser2448) is suppressed while mTORC1, PI3K and mTORC2 activities increase. mTORC1 substrate p70S6K becomes highly phosphorylated while its activity, now regulated by mTORC2, is required for LC3-II formation. Inhibition of mTORC2/p70S6K, unlike that of PI3K/mTORC1, blocks expanded autophagy in the absence of apoptosis but not moderate autophagy. Inhibitors of expanded autophagy limit virus reproduction. Thus expanded, lethal autophagy is activated by a signaling mechanism different from autophagy that helps cells survive toxic or stressful episodes.
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Affiliation(s)
- Emmanuel Datan
- Department of Biology, Queens College and Graduate Center of the City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA
| | - Alireza Shirazian
- Department of Biology, Queens College and Graduate Center of the City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA
| | - Shawna Benjamin
- Department of Biology, Queens College and Graduate Center of the City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA
| | - Demetrius Matassov
- Department of Biology, Queens College and Graduate Center of the City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA
| | - Antonella Tinari
- Department of Technology and Health, Instituto Superiore di Sanita, Viale Regina Elena 299, 00161 Rome, Italy
| | - Walter Malorni
- Department of Drug Research and Evaluation, Instituto Superiore di Sanita, Viale Regina Elena 299, 00161 Rome, Italy.,San Raffaele Institute Sulmona, 67039 L'Aquila, Italy
| | - Richard A Lockshin
- Department of Biology, Queens College and Graduate Center of the City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA
| | - Adolfo Garcia-Sastre
- Department of Microbiology, Division of Infectious Diseases, Mount Sinai School of Medicine, New York, NY 10029, USA.,Global Health and Emerging Pathogens Institute, Division of Infectious Diseases, Mount Sinai School of Medicine, New York, NY 10029, USA.,Global Health and Emerging Pathogens Institute, Division of Infectious Diseases, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Zahra Zakeri
- Department of Biology, Queens College and Graduate Center of the City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA
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25
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Adenovirus death protein (ADP) is required for lytic infection of human lymphocytes. J Virol 2013; 88:903-12. [PMID: 24198418 DOI: 10.1128/jvi.01675-13] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The adenovirus death protein (ADP) is expressed at late times during a lytic infection of species C adenoviruses. ADP promotes the release of progeny virus by accelerating the lysis and death of the host cell. Since some human lymphocytes survive while maintaining a persistent infection with species C adenovirus, we compared ADP expression in these cells with ADP expression in lymphocytes that proceed with a lytic infection. Levels of ADP were low in KE37 and BJAB cells, which support a persistent infection. In contrast, levels of ADP mRNA and protein were higher in Jurkat cells, which proceed with a lytic infection. Epithelial cells infected with an ADP-overexpressing virus died more quickly than epithelial cells infected with an ADP-deleted virus. However, KE37, and BJAB cells remained viable after infection with the ADP-overexpressing virus. Although the levels of ADP mRNA increased in KE37 and BJAB cells infected with the ADP-overexpressing virus, the fraction of cells with detectable ADP was unchanged, suggesting that the control of ADP expression differs between epithelial and lymphocytic cells. When infected with an ADP-deleted adenovirus, Jurkat cells survived and maintained viral DNA for greater than 1 month. These findings are consistent with the notion that the level of ADP expression determines whether lymphocytic cells proceed with a lytic or a persistent adenovirus infection.
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