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Miller K, McGrath ME, Hu Z, Ariannejad S, Weston S, Frieman M, Jackson WT. Coronavirus interactions with the cellular autophagy machinery. Autophagy 2020; 16:2131-2139. [PMID: 32964796 PMCID: PMC7755319 DOI: 10.1080/15548627.2020.1817280] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 12/15/2022] Open
Abstract
The COVID-19 pandemic, caused by the SARS-CoV-2 virus, is the most recent example of an emergent coronavirus that poses a significant threat to human health. Virus-host interactions play a major role in the viral life cycle and disease pathogenesis, and cellular pathways such as macroautophagy/autophagy prove to be either detrimental or beneficial to viral replication and maturation. Here, we describe the literature over the past twenty years describing autophagy-coronavirus interactions. There is evidence that many coronaviruses induce autophagy, although some of these viruses halt the progression of the pathway prior to autophagic degradation. In contrast, other coronaviruses usurp components of the autophagy pathway in a non-canonical fashion. Cataloging these virus-host interactions is crucial for understanding disease pathogenesis, especially with the global challenge of SARS-CoV-2 and COVID-19. With the recognition of autophagy inhibitors, including the controversial drug chloroquine, as possible treatments for COVID-19, understanding how autophagy affects the virus will be critical going forward. Abbreviations: 3-MA: 3-methyladenine (autophagy inhibitor); AKT/protein kinase B: AKT serine/threonine kinase; ATG: autophagy related; ATPase: adenosine triphosphatase; BMM: bone marrow macrophage; CGAS: cyclic GMP-AMP synthase; CHO: Chinese hamster ovary/cell line; CoV: coronaviruses; COVID-19: Coronavirus disease 2019; DMV: double-membrane vesicle; EAV: equine arteritis virus; EDEM1: ER degradation enhancing alpha-mannosidase like protein 1; ER: endoplasmic reticulum; ERAD: ER-associated degradation; GFP: green fluorescent protein; HCoV: human coronavirus; HIV: human immunodeficiency virus; HSV: herpes simplex virus; IBV: infectious bronchitis virus; IFN: interferon; LAMP1: lysosomal associated membrane protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MCoV: mouse coronavirus; MERS-CoV: Middle East respiratory syndrome coronavirus; MHV: mouse hepatitis virus; NBR1: NBR1 autophagy cargo receptor; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2 (autophagy receptor that directs cargo to phagophores); nsp: non-structural protein; OS9: OS9 endoplasmic reticulum lectin; PEDV: porcine epidemic diarrhea virus; PtdIns3K: class III phosphatidylinositol 3-kinase; PLP: papain-like protease; pMEF: primary mouse embryonic fibroblasts; SARS-CoV: severe acute respiratory syndrome coronavirus; SKP2: S-phase kinase associated protein 2; SQSTM1: sequestosome 1; STING1: stimulator of interferon response cGAMP interactor 1; ULK1: unc-51 like autophagy activating kinase 1; Vps: vacuolar protein sorting.
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Affiliation(s)
- Katelyn Miller
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Marisa E. McGrath
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Zhiqiang Hu
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Sohha Ariannejad
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Stuart Weston
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Matthew Frieman
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - William T Jackson
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
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Shojaei S, Suresh M, Klionsky DJ, Labouta HI, Ghavami S. Autophagy and SARS-CoV-2 infection: Apossible smart targeting of the autophagy pathway. Virulence 2020; 11:805-810. [PMID: 32567972 PMCID: PMC7549903 DOI: 10.1080/21505594.2020.1780088] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 06/05/2020] [Indexed: 01/04/2023] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak resulted in 5,993,317 confirmed cases worldwide with 365,394 confirmed deaths (as of May 29th, 2020, WHO). The molecular mechanism of virus infection and spread in the body is not yet disclosed, but studies on other betacoronaviruses show that, upon cell infection, these viruses inhibit macroautophagy/autophagy flux and cause the accumulation of autophagosomes. No drug has yet been approved for the treatment of SARS-CoV-2 infection; however, preclinical investigations suggested repurposing of several FDA-approved drugs for clinical trials. Half of these drugs are modulators of the autophagy pathway. Unexpectedly, instead of acting by directly antagonizing the effects of viruses, these drugs appear to function by suppressing autophagy flux. Based on the established cross-talk between autophagy and apoptosis, we speculate that over-accumulation of autophagosomes activates an apoptotic pathway that results in apoptotic death of the infected cells and disrupts the virus replication cycle. However, administration of the suggested drugs are associated with severe adverse effects due to their off-target accumulation. Nanoparticle targeting of autophagy at the sites of interest could be a powerful tool to efficiently overcome SARS-CoV-2 infection while avoiding the common adverse effects of these drugs.
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Affiliation(s)
- Shahla Shojaei
- College of Pharmacy, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Madhumita Suresh
- College of Pharmacy, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Daniel J. Klionsky
- Life Sciences Institute and Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Hagar Ibrahim Labouta
- College of Pharmacy, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
- Children’s Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
- Biomedical Engineering Program, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Saeid Ghavami
- Children’s Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
- Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
- Research Institute in Oncology and Hematology, CancerCare Manitoba, University of Manitoba, Winnipeg, Manitoba, Canada
- Autophagy Research Centre, Health Policy Research Center, Institute of Health, Shiraz University of Medical Sciences, Shiraz, Iran
- Faculty of Medicine, Katowice School of Technology, Katowice, Poland
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Delorme-Axford E, Klionsky DJ. Highlights in the fight against COVID-19: does autophagy play a role in SARS-CoV-2 infection? Autophagy 2020; 16:2123-2127. [PMID: 33153403 PMCID: PMC7651184 DOI: 10.1080/15548627.2020.1844940] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Indexed: 12/18/2022] Open
Abstract
In the preceding months, the novel SARS-CoV-2 pandemic has devastated global communities. The need for safe and effective prophylactic and therapeutic treatments to combat COVID-19 - the human disease resulting from SARS-CoV-2 infection - is clear. Here, we present recent developments in the effort to combat COVID-19 and consider whether SARS-CoV-2 may potentially interact with the host autophagy pathway. Abbreviations: ACE2, angiotensin converting enzyme II; βCoV, betacoronavirus; COVID-19, Coronavirus Disease 2019; CQ, chloroquine; DMV, double-membrane vesicle; GI, gastrointestinal; HCQ, hydroxychloroquine; IL, interleukin; MAP1LC3/LC3, microtubule associated protein 1 light chain 3; MEFs, mouse embryonic fibroblasts; MERS-CoV, Middle East respiratory syndrome coronavirus; MHV, murine hepatitis virus; PE, phosphatidylethanolamine; SARS-CoV, severe acute respiratory syndrome coronavirus; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; TMPRSS2, transmembrane serine protease 2; TNF, tumor necrosis factor; WHO, World Health Organization.
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Domdom MA, Brest P, Grosjean I, Roméo B, Landi MT, Gal J, Klionsky DJ, Hofman P, Mograbi B. A multifactorial score including autophagy for prognosis and care of COVID-19 patients. Autophagy 2020; 16:2276-2281. [PMID: 33249989 PMCID: PMC7751655 DOI: 10.1080/15548627.2020.1844433] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/21/2020] [Accepted: 10/27/2020] [Indexed: 02/06/2023] Open
Abstract
In less than eleven months, the world was brought to a halt by the COVID-19 outbreak. With hospitals becoming overwhelmed, one of the highest priorities concerned critical care triage to ration the scarce resources of intensive care units. Which patient should be treated first? Based on what clinical and biological criteria? A global joint effort rapidly led to sequencing the genomes of tens of thousands of COVID-19 patients to determine the patients' genetic signature that causes them to be at risk of suddenly developing severe disease. In this commentary, we would like to consider some points concerning the use of a multifactorial risk score for COVID-19 severity. This score includes macroautophagy (hereafter referred to as autophagy), a critical host process that controls all steps harnessed by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Abbreviation list: ATG5: autophagy related 5; BECN1: beclin 1; COVID-19: coronavirus infectious disease-2019; EGR1: early growth response 1; ER: endoplasmic reticulum; DMVs: double-membrane vesicles; IBV: infectious bronchitis virus; MAP1LC3: microtubule associated protein 1 light chain 3; LC3-I: proteolytically processed, non-lipidated MAP1LC3; LC3-II: lipidated MAP1LC3; MEFs: mouse embryonic fibroblasts; MERS-CoV: Middle East respiratory syndrome-coronavirus; MHV: mouse hepatitis virus; NSP: non-structural protein; PEDV: porcine epidemic diarrhea virus; PLP2-TM: membrane-associated papain-like protease 2; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; TGEV: transmissible gastroenteritis virus.
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Affiliation(s)
- Marie-Angela Domdom
- Université Côte d’Azur, CNRS, INSERM, IRCAN, FHU-OncoAge, Centre Antoine Lacassagne, Nice, France
| | - Patrick Brest
- Université Côte d’Azur, CNRS, INSERM, IRCAN, FHU-OncoAge, Centre Antoine Lacassagne, Nice, France
| | - Iris Grosjean
- Université Côte d’Azur, CNRS, INSERM, IRCAN, FHU-OncoAge, Centre Antoine Lacassagne, Nice, France
| | - Barnabé Roméo
- Université Côte d’Azur, CNRS, INSERM, IRCAN, FHU-OncoAge, Centre Antoine Lacassagne, Nice, France
| | - Maria Teresa Landi
- Division of Cancer Epidemiology and Genetics,National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jocelyn Gal
- University Côte d’Azur, Centre Antoine Lacassagne, Epidemiology and Biostatistics Department, Nice, France
| | - Daniel J. Klionsky
- University of Michigan, Department of Molecular, Cellular, and Developmental Biology, and Life Sciences Institute, Ann Arbor, MI, USA
| | - Paul Hofman
- Université Côte d’Azur, CNRS, INSERM, IRCAN, FHU-OncoAge, Centre Antoine Lacassagne, Nice, France
- Université Côte d’Azur, Centre Hospitallier Universitaire De Nice, Pasteur Hospital, Laboratory of Clinical and Experimental Pathology, and Biobank (BB003300025), Nice, France
| | - Baharia Mograbi
- Université Côte d’Azur, CNRS, INSERM, IRCAN, FHU-OncoAge, Centre Antoine Lacassagne, Nice, France
- TRANSAUTOPHAGY: European Network for Multidisciplinary Research and Translation of Autophagy Knowledge, COST Action CA15138
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Randhawa PK, Scanlon K, Rappaport J, Gupta MK. Modulation of Autophagy by SARS-CoV-2: A Potential Threat for Cardiovascular System. Front Physiol 2020; 11:611275. [PMID: 33329064 PMCID: PMC7734100 DOI: 10.3389/fphys.2020.611275] [Citation(s) in RCA: 12] [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: 09/28/2020] [Accepted: 11/09/2020] [Indexed: 12/15/2022] Open
Abstract
Recently, we have witnessed an unprecedented increase in the number of patients suffering from respiratory tract illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The COVID-19 virus is a single-stranded positive-sense RNA virus with a genome size of ~29.9 kb. It is believed that the viral spike (S) protein attaches to angiotensin converting enzyme 2 cell surface receptors and, eventually, the virus gains access into the host cell with the help of intracellular/extracellular proteases or by the endosomal pathway. Once, the virus enters the host cell, it can either be degraded via autophagy or evade autophagic degradation and replicate using the virus encoded RNA dependent RNA polymerase. The virus is highly contagious and can impair the respiratory system of the host causing dyspnea, cough, fever, and tightness in the chest. This disease is also characterized by an abrupt upsurge in the levels of proinflammatory/inflammatory cytokines and chemotactic factors in a process known as cytokine storm. Certain reports have suggested that COVID-19 infection can aggravate cardiovascular complications, in fact, the individuals with underlying co-morbidities are more prone to the disease. In this review, we shall discuss the pathogenesis, clinical manifestations, potential drug candidates, the interaction between virus and autophagy, and the role of coronavirus in exaggerating cardiovascular complications.
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Affiliation(s)
- Puneet Kaur Randhawa
- Division of Metabolic and Cardiovascular Sciences, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States
| | - Kaylyn Scanlon
- Division of Metabolic and Cardiovascular Sciences, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States
| | - Jay Rappaport
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, United States
| | - Manish K. Gupta
- Division of Metabolic and Cardiovascular Sciences, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States
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Vela JM. Repurposing Sigma-1 Receptor Ligands for COVID-19 Therapy? Front Pharmacol 2020; 11:582310. [PMID: 33364957 PMCID: PMC7751758 DOI: 10.3389/fphar.2020.582310] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 09/30/2020] [Indexed: 12/27/2022] Open
Abstract
Outbreaks of emerging infections, such as COVID-19 pandemic especially, confront health professionals with the unique challenge of treating patients. With no time to discover new drugs, repurposing of approved drugs or in clinical development is likely the only solution. Replication of coronaviruses (CoVs) occurs in a modified membranous compartment derived from the endoplasmic reticulum (ER), causes host cell ER stress and activates pathways to facilitate adaptation of the host cell machinery to viral needs. Accordingly, modulation of ER remodeling and ER stress response might be pivotal in elucidating CoV-host interactions and provide a rationale for new therapeutic, host-based antiviral approaches. The sigma-1 receptor (Sig-1R) is a ligand-operated, ER membrane-bound chaperone that acts as an upstream modulator of ER stress and thus a candidate host protein for host-based repurposing approaches to treat COVID-19 patients. Sig-1R ligands are frequently identified in in vitro drug repurposing screens aiming to identify antiviral compounds against CoVs, including severe acute respiratory syndrome CoV-2 (SARS-CoV-2). Sig-1R regulates key mechanisms of the adaptive host cell stress response and takes part in early steps of viral replication. It is enriched in lipid rafts and detergent-resistant ER membranes, where it colocalizes with viral replicase proteins. Indeed, the non-structural SARS-CoV-2 protein Nsp6 interacts with Sig-1R. The activity of Sig-1R ligands against COVID-19 remains to be specifically assessed in clinical trials. This review provides a rationale for targeting Sig-1R as a host-based drug repurposing approach to treat COVID-19 patients. Evidence gained using Sig-1R ligands in unbiased in vitro antiviral drug screens and the potential mechanisms underlying the modulatory effect of Sig-1R on the host cell response are discussed. Targeting Sig-1R is not expected to reduce dramatically established viral replication, but it might interfere with early steps of virus-induced host cell reprogramming, aid to slow down the course of infection, prevent the aggravation of the disease and/or allow a time window to mature a protective immune response. Sig-1R-based medicines could provide benefit not only as early intervention, preventive but also as adjuvant therapy.
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Affiliation(s)
- José Miguel Vela
- Drug Discovery and Preclinical Development, ESTEVE Pharmaceuticals, Barcelona, Spain
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57
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Kanakan A, Mishra N, Srinivasa Vasudevan J, Sahni S, Khan A, Sharma S, Pandey R. Threading the Pieces Together: Integrative Perspective on SARS-CoV-2. Pathogens 2020; 9:E912. [PMID: 33158051 PMCID: PMC7694192 DOI: 10.3390/pathogens9110912] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 02/07/2023] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has challenged the research community globally to innovate, interact, and integrate findings across hierarchies. Research on SARS-CoV-2 has produced an abundance of data spanning multiple parallels, including clinical data, SARS-CoV-2 genome architecture, host response captured through transcriptome and genetic variants, microbial co-infections (metagenome), and comorbidities. Disease phenotypes in the case of COVID-19 present an intriguing complexity that includes a broad range of symptomatic to asymptomatic individuals, further compounded by a vast heterogeneity within the spectrum of clinical symptoms displayed by the symptomatic individuals. The clinical outcome is further modulated by the presence of comorbid conditions at the point of infection. The COVID-19 pandemic has produced an expansive wealth of literature touching many aspects of SARS-CoV-2 ranging from causal to outcome, predisposition to protective (possible), co-infection to comorbidity, and differential mortality globally. As challenges provide opportunities, the current pandemic's challenge has underscored the need and opportunity to work for an integrative approach that may be able to thread together the multiple variables. Through this review, we have made an effort towards bringing together information spanning across different domains to facilitate researchers globally in pursuit of their response to SARS-CoV-2.
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Affiliation(s)
| | | | | | | | | | | | - Rajesh Pandey
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) Laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Delhi 110007, India; (A.K.); (N.M.); (J.S.V.); (S.S.); (A.K.); (S.S.)
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58
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Khan N, Chen X, Geiger JD. Role of Endolysosomes in Severe Acute Respiratory Syndrome Coronavirus-2 Infection and Coronavirus Disease 2019 Pathogenesis: Implications for Potential Treatments. Front Pharmacol 2020; 11:595888. [PMID: 33324224 PMCID: PMC7723437 DOI: 10.3389/fphar.2020.595888] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/05/2020] [Indexed: 12/14/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an enveloped, single-stranded RNA virus. Humans infected with SARS-CoV-2 develop a disease known as coronavirus disease 2019 (COVID-19) with symptoms and consequences including acute respiratory distress syndrome (ARDS), cardiovascular disorders, and death. SARS-CoV-2 appears to infect cells by first binding viral spike proteins with host protein angiotensin-converting enzyme 2 (ACE2) receptors; the virus is endocytosed following priming by transmembrane protease serine 2 (TMPRSS2). The process of virus entry into endosomes and its release from endolysosomes are key features of enveloped viruses. Thus, it is important to focus attention on the role of endolysosomes in SARS-CoV-2 infection. Indeed, coronaviruses are now known to hijack endocytic machinery to enter cells such that they can deliver their genome at replication sites without initiating host detection and immunological responses. Hence, endolysosomes might be good targets for developing therapeutic strategies against coronaviruses. Here, we focus attention on the involvement of endolysosomes in SARS-CoV-2 infection and COVID-19 pathogenesis. Further, we explore endolysosome-based therapeutic strategies to restrict SARS-CoV-2 infection and COVID-19 pathogenesis.
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Affiliation(s)
| | | | - Jonathan D. Geiger
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, United States
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Khalaf K, Papp N, Chou JTT, Hana D, Mackiewicz A, Kaczmarek M. SARS-CoV-2: Pathogenesis, and Advancements in Diagnostics and Treatment. Front Immunol 2020; 11:570927. [PMID: 33123144 PMCID: PMC7573101 DOI: 10.3389/fimmu.2020.570927] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/04/2020] [Indexed: 12/15/2022] Open
Abstract
The emergence and rapid spread of SARS-CoV-2 in December 2019 has brought the world to a standstill. While less pathogenic than the 2002-2003 SARS-CoV, this novel betacoronavirus presents a global threat due to its high transmission rate, ability to invade multiple tissues, and ability to trigger immunological hyperactivation. The identification of the animal reservoir and intermediate host were important steps toward slowing the spread of disease, and its genetic similarity to SARS-CoV has helped to determine pathogenesis and direct treatment strategies. The exponential increase in cases has necessitated fast and reliable testing procedures. Although RT-PCR remains the gold standard, it is a time-consuming procedure, paving the way for newer techniques such as serologic tests and enzyme immunoassays. Various clinical trials using broad antiviral agents in addition to novel medications have produced controversial results; however, the advancement of immunotherapy, particularly monoclonal antibodies and immune modulators is showing great promise in clinical trials. Non-orthodox medications such as anti-malarials have been tested in multiple institutions but definitive conclusions are yet to be made. Adjuvant therapies have also proven to be effective in decreasing mortality in the disease course. While no formal guidelines have been established, the multitude of ongoing clinical trials as a result of unprecedented access to research data brings us closer to halting the SARS-CoV-2 pandemic.
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Affiliation(s)
- Khalil Khalaf
- Department of Cancer Immunology, Poznan University of Medical Sciences, Poznań, Poland
| | - Natalia Papp
- Department of Cancer Immunology, Poznan University of Medical Sciences, Poznań, Poland
| | - Jadzia Tin-Tsen Chou
- Department of Cancer Immunology, Poznan University of Medical Sciences, Poznań, Poland
| | - Doris Hana
- Department of Cancer Immunology, Poznan University of Medical Sciences, Poznań, Poland
| | - Andrzej Mackiewicz
- Department of Cancer Immunology, Poznan University of Medical Sciences, Poznań, Poland
- Department of Cancer Diagnostics and Immunology, Greater Poland Cancer Center, Poznań, Poland
| | - Mariusz Kaczmarek
- Department of Cancer Immunology, Poznan University of Medical Sciences, Poznań, Poland
- Department of Cancer Diagnostics and Immunology, Greater Poland Cancer Center, Poznań, Poland
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Vallamkondu J, John A, Wani WY, Ramadevi SP, Jella KK, Reddy PH, Kandimalla R. SARS-CoV-2 pathophysiology and assessment of coronaviruses in CNS diseases with a focus on therapeutic targets. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165889. [PMID: 32603829 PMCID: PMC7320676 DOI: 10.1016/j.bbadis.2020.165889] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/23/2020] [Accepted: 06/24/2020] [Indexed: 02/06/2023]
Abstract
The novel Coronavirus disease of 2019 (nCOV-19) is a viral outbreak noted first in Wuhan, China. This disease is caused by Severe Acute Respiratory Syndrome (SARS) Coronavirus (CoV)-2. In the past, other members of the coronavirus family, such as SARS and Middle East Respiratory Syndrome (MERS), have made an impact in China and the Arabian peninsula respectively. Both SARS and COVID-19 share similar symptoms such as fever, cough, and difficulty in breathing that can become fatal in later stages. However, SARS and MERS infections were epidemic diseases constrained to limited regions. By March 2020 the SARS-CoV-2 had spread across the globe and on March 11th, 2020 the World Health Organization (WHO) declared COVID-19 as pandemic disease. In severe SARS-CoV-2 infection, many patients succumbed to pneumonia. Higher rates of deaths were seen in older patients who had co-morbidities such as diabetes mellitus, hypertension, cardiovascular disease (CVD), and dementia. In this review paper, we discuss the effect of SARS-CoV-2 on CNS diseases, such as Alzheimer's-like dementia, and diabetes mellitus. We also focus on the virus genome, pathophysiology, theranostics, and autophagy mechanisms. We will assess the multiorgan failure reported in advanced stages of SARS-CoV-2 infection. Our paper will provide mechanistic clues and therapeutic targets for physicians and investigators to combat COVID-19.
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Affiliation(s)
| | - Albin John
- Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Willayat Yousuf Wani
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, United States
| | | | | | - P Hemachandra Reddy
- Professor of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Internal Medicine, Neuroscience & Pharmacology, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Neurology, Departments of School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Public Health Department of Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Department of Speech, Language and Hearing Sciences, School Health Professions, Texas Tech University Health Sciences Center, Lubbock, TX, USA.
| | - Ramesh Kandimalla
- Department of Biochemistry, Kakatiya Medical College, Warangal 506007, Telangana, India; Applied Biology, CSIR-Indian Institute of Technology, Uppal Road, Tarnaka, Hyderabad 500007, Telangana, India.
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Aslam M, Ladilov Y. Targeting the sAC-Dependent cAMP Pool to Prevent SARS-Cov-2 Infection. Cells 2020; 9:cells9091962. [PMID: 32854430 PMCID: PMC7563949 DOI: 10.3390/cells9091962] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/24/2020] [Accepted: 08/24/2020] [Indexed: 12/11/2022] Open
Abstract
An outbreak of the novel coronavirus (CoV) SARS-CoV-2, the causative agent of COVID-19 respiratory disease, infected millions of people since the end of 2019, led to high-level morbidity and mortality and caused worldwide social and economic disruption. There are currently no antiviral drugs available with proven efficacy or vaccines for its prevention. An understanding of the underlying cellular mechanisms involved in virus replication is essential for repurposing the existing drugs and/or the discovery of new ones. Endocytosis is the important mechanism of entry of CoVs into host cells. Endosomal maturation followed by the fusion with lysosomes are crucial events in endocytosis. Late endosomes and lysosomes are characterized by their acidic pH, which is generated by a proton transporter V-ATPase and required for virus entry via endocytic pathway. The cytoplasmic cAMP pool produced by soluble adenylyl cyclase (sAC) promotes V-ATPase recruitment to endosomes/lysosomes and thus their acidification. In this review, we discuss targeting the sAC-specific cAMP pool as a potential strategy to impair the endocytic entry of the SARS-CoV-2 into the host cell. Furthermore, we consider the potential impact of sAC inhibition on CoV-induced disease via modulation of autophagy and apoptosis.
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Affiliation(s)
- Muhammad Aslam
- Experimental Cardiology, Department of Internal Medicine, Justus Liebig University, 35392 Giessen, Germany;
- DZHK (German Centre for Cardiovascular Research), Department of Cardiology, Kerckhoff Clinic GmbH partner site Rhein-Main, 61231 Bad Nauheim, Germany
| | - Yury Ladilov
- Independent Researcher, 42929 Wermelskirchen, Germany
- Correspondence:
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Silvas JA, Jureka AS, Nicolini AM, Chvatal SA, Basler CF. Inhibitors of VPS34 and lipid metabolism suppress SARS-CoV-2 replication. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.07.18.210211. [PMID: 32743584 PMCID: PMC7386504 DOI: 10.1101/2020.07.18.210211] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Therapeutics targeting replication of SARS coronavirus 2 (SARS-CoV-2) are urgently needed. Coronaviruses rely on host membranes for entry, establishment of replication centers and egress. Compounds targeting cellular membrane biology and lipid biosynthetic pathways have previously shown promise as antivirals and are actively being pursued as treatments for other conditions. Here, we tested small molecule inhibitors that target membrane dynamics or lipid metabolism. Included were inhibitors of the PI3 kinase VPS34, which functions in autophagy, endocytosis and other processes; Orlistat, an inhibitor of lipases and fatty acid synthetase, is approved by the FDA as a treatment for obesity; and Triacsin C which inhibits long chain fatty acyl-CoA synthetases. VPS34 inhibitors, Orlistat and Triacsin C inhibited virus growth in Vero E6 cells and in the human airway epithelial cell line Calu-3, acting at a post-entry step in the virus replication cycle. Of these the VPS34 inhibitors exhibit the most potent activity.
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Affiliation(s)
- Jesus A. Silvas
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, 30303
- Equal contribution
| | - Alexander S. Jureka
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, 30303
- Equal contribution
| | | | | | - Christopher F. Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, 30303
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63
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Bello-Perez M, Sola I, Novoa B, Klionsky DJ, Falco A. Canonical and Noncanonical Autophagy as Potential Targets for COVID-19. Cells 2020; 9:E1619. [PMID: 32635598 PMCID: PMC7408018 DOI: 10.3390/cells9071619] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 06/29/2020] [Accepted: 07/01/2020] [Indexed: 02/06/2023] Open
Abstract
The SARS-CoV-2 pandemic necessitates a review of the molecular mechanisms underlying cellular infection by coronaviruses, in order to identify potential therapeutic targets against the associated new disease (COVID-19). Previous studies on its counterparts prove a complex and concomitant interaction between coronaviruses and autophagy. The precise manipulation of this pathway allows these viruses to exploit the autophagy molecular machinery while avoiding its protective apoptotic drift and cellular innate immune responses. In turn, the maneuverability margins of such hijacking appear to be so narrow that the modulation of the autophagy, regardless of whether using inducers or inhibitors (many of which are FDA-approved for the treatment of other diseases), is usually detrimental to viral replication, including SARS-CoV-2. Recent discoveries indicate that these interactions stretch into the still poorly explored noncanonical autophagy pathway, which might play a substantial role in coronavirus replication. Still, some potential therapeutic targets within this pathway, such as RAB9 and its interacting proteins, look promising considering current knowledge. Thus, the combinatory treatment of COVID-19 with drugs affecting both canonical and noncanonical autophagy pathways may be a turning point in the fight against this and other viral infections, which may also imply beneficial prospects of long-term protection.
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Affiliation(s)
- Melissa Bello-Perez
- Department of Molecular and Cell Biology, National Center of Biotechnology (CNB-CSIC), Campus Universidad Autónoma de Madrid, Darwin 3, 28049 Madrid, Spain; (M.B.-P.); (I.S.)
| | - Isabel Sola
- Department of Molecular and Cell Biology, National Center of Biotechnology (CNB-CSIC), Campus Universidad Autónoma de Madrid, Darwin 3, 28049 Madrid, Spain; (M.B.-P.); (I.S.)
| | - Beatriz Novoa
- Institute of Marine Research (IIM), National Research Council (CSIC), 36208 Vigo, Spain;
| | - Daniel J. Klionsky
- Life Sciences Institute and Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA;
| | - Alberto Falco
- Institute of Research, Development, and Innovation in Healthcare Biotechnology in Elche (IDiBE), Miguel Hernández University (UMH), 03202 Elche, Spain
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64
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Carmona-Gutierrez D, Bauer MA, Zimmermann A, Kainz K, Hofer SJ, Kroemer G, Madeo F. Digesting the crisis: autophagy and coronaviruses. MICROBIAL CELL (GRAZ, AUSTRIA) 2020; 7:119-128. [PMID: 32391393 PMCID: PMC7199282 DOI: 10.15698/mic2020.05.715] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 01/08/2023]
Abstract
Autophagy is a catabolic pathway with multifaceted roles in cellular homeostasis. This process is also involved in the antiviral response at multiple levels, including the direct elimination of intruding viruses (virophagy), the presentation of viral antigens, the fitness of immune cells, and the inhibition of excessive inflammatory reactions. In line with its central role in immunity, viruses have evolved mechanisms to interfere with or to evade the autophagic process, and in some cases, even to harness autophagy or constituents of the autophagic machinery for their replication. Given the devastating consequences of the current COVID-19 pandemic, the question arises whether manipulating autophagy might be an expedient approach to fight the novel coronavirus SARS-CoV-2. In this piece, we provide a short overview of the evidence linking autophagy to coronaviruses and discuss whether such links may provide actionable targets for therapeutic interventions.
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Affiliation(s)
| | - Maria A. Bauer
- Institute for Molecular Biosciences, NAWI Graz, University of Graz, Graz, Austria
| | - Andreas Zimmermann
- Institute for Molecular Biosciences, NAWI Graz, University of Graz, Graz, Austria
- BioHealth Graz, Graz, Austria
| | - Katharina Kainz
- Institute for Molecular Biosciences, NAWI Graz, University of Graz, Graz, Austria
| | - Sebastian J. Hofer
- Institute for Molecular Biosciences, NAWI Graz, University of Graz, Graz, Austria
| | - Guido Kroemer
- Centre de Recherche des Cordeliers, Equipe labellisée par la Ligue contre le cancer, Université de Paris, Sorbonne Université, INSERM U1138, Institut Universitaire de France, Paris, France
- Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, Villejuif, France
- Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France
- Suzhou Institute for Systems Medicine, Chinese Academy of Medical Sciences, Suzhou, China
- Karolinska Institute, Department of Women's and Children's Health, Karolinska University Hospital, Stockholm, Sweden
| | - Frank Madeo
- Institute for Molecular Biosciences, NAWI Graz, University of Graz, Graz, Austria
- BioHealth Graz, Graz, Austria
- BioTechMed Graz, Graz, Austria
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65
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Wong HH, Sanyal S. Manipulation of autophagy by (+) RNA viruses. Semin Cell Dev Biol 2020; 101:3-11. [PMID: 31382014 PMCID: PMC7102625 DOI: 10.1016/j.semcdb.2019.07.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 06/11/2019] [Accepted: 07/30/2019] [Indexed: 01/07/2023]
Abstract
Autophagy is an evolutionarily conserved process central to host metabolism. Among its major functions are conservation of energy during starvation, recycling organelles, and turnover of long-lived proteins. Besides, autophagy plays a critical role in removing intracellular pathogens and very likely represents a primordial intrinsic cellular defence mechanism. More recent findings indicate that it has not only retained its ability to degrade intracellular pathogens, but also functions to augment and fine tune antiviral immune responses. Interestingly, viruses have also co-evolved strategies to manipulate this pathway and use it to their advantage. Particularly intriguing is infection-dependent activation of autophagy with positive stranded (+)RNA virus infections, which benefit from the pathway without succumbing to lysosomal degradation. In this review we summarise recent data on viral manipulation of autophagy, with a particular emphasis on +RNA viruses and highlight key unanswered questions in the field that we believe merit further attention.
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Affiliation(s)
- Ho Him Wong
- HKU-Pasteur Research Pole, School of Public Health, University of Hong Kong, Hong Kong
| | - Sumana Sanyal
- HKU-Pasteur Research Pole, School of Public Health, University of Hong Kong, Hong Kong,School of Biomedical Sciences, LKS Faculty of Medicine, University of Hong Kong, Hong Kong,Corresponding author at: HKU-Pasteur Research Pole, School of Public Health, University of Hong Kong, Hong Kong
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66
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Yang N, Shen HM. Targeting the Endocytic Pathway and Autophagy Process as a Novel Therapeutic Strategy in COVID-19. Int J Biol Sci 2020; 16:1724-1731. [PMID: 32226290 PMCID: PMC7098027 DOI: 10.7150/ijbs.45498] [Citation(s) in RCA: 309] [Impact Index Per Article: 77.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 03/03/2020] [Indexed: 12/23/2022] Open
Abstract
Coronaviruses (CoVs) are a group of enveloped, single-stranded positive genomic RNA viruses and some of them are known to cause severe respiratory diseases in human, including Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS) and the ongoing coronavirus disease-19 (COVID-19). One key element in viral infection is the process of viral entry into the host cells. In the last two decades, there is increasing understanding on the importance of the endocytic pathway and the autophagy process in viral entry and replication. As a result, the endocytic pathway including endosome and lysosome has become important targets for development of therapeutic strategies in combating diseases caused by CoVs. In this mini-review, we will focus on the importance of the endocytic pathway as well as the autophagy process in viral infection of several pathogenic CoVs inclusive of SARS-CoV, MERS-CoV and the new CoV named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and discuss the development of therapeutic agents by targeting these processes. Such knowledge will provide important clues for control of the ongoing epidemic of SARS-CoV-2 infection and treatment of COVID-19.
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Affiliation(s)
- Naidi Yang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, Jiangsu Province 211800, China
| | - Han-Ming Shen
- Faculty of Health Sciences, University of Macau, Macau SAR, China
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67
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Gassen NC, Niemeyer D, Muth D, Corman VM, Martinelli S, Gassen A, Hafner K, Papies J, Mösbauer K, Zellner A, Zannas AS, Herrmann A, Holsboer F, Brack-Werner R, Boshart M, Müller-Myhsok B, Drosten C, Müller MA, Rein T. SKP2 attenuates autophagy through Beclin1-ubiquitination and its inhibition reduces MERS-Coronavirus infection. Nat Commun 2019; 10:5770. [PMID: 31852899 PMCID: PMC6920372 DOI: 10.1038/s41467-019-13659-4] [Citation(s) in RCA: 250] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 11/14/2019] [Indexed: 12/18/2022] Open
Abstract
Autophagy is an essential cellular process affecting virus infections and other diseases and Beclin1 (BECN1) is one of its key regulators. Here, we identified S-phase kinase-associated protein 2 (SKP2) as E3 ligase that executes lysine-48-linked poly-ubiquitination of BECN1, thus promoting its proteasomal degradation. SKP2 activity is regulated by phosphorylation in a hetero-complex involving FKBP51, PHLPP, AKT1, and BECN1. Genetic or pharmacological inhibition of SKP2 decreases BECN1 ubiquitination, decreases BECN1 degradation and enhances autophagic flux. Middle East respiratory syndrome coronavirus (MERS-CoV) multiplication results in reduced BECN1 levels and blocks the fusion of autophagosomes and lysosomes. Inhibitors of SKP2 not only enhance autophagy but also reduce the replication of MERS-CoV up to 28,000-fold. The SKP2-BECN1 link constitutes a promising target for host-directed antiviral drugs and possibly other autophagy-sensitive conditions. Here, Gassen et al. show that S-phase kinase-associated protein 2 (SKP2) is responsible for lysine-48-linked poly-ubiquitination of beclin 1, resulting in its proteasomal degradation, and that inhibition of SKP2 enhances autophagy and reduces replication of MERS coronavirus.
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Affiliation(s)
- Nils C Gassen
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany. .,Department of Psychiatry and Psychotherapy, University of Bonn, Venusberg Campus 1, 53127, Bonn, Germany.
| | - Daniela Niemeyer
- Institute of Virology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | - Doreen Muth
- Institute of Virology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | - Victor M Corman
- Institute of Virology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | - Silvia Martinelli
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany
| | - Alwine Gassen
- Faculty of Biology, Genetics, Ludwig-Maximilian-University Munich (LMU), 82152, Martinsried, Germany
| | - Kathrin Hafner
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany
| | - Jan Papies
- Institute of Virology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | - Kirstin Mösbauer
- Institute of Virology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | - Andreas Zellner
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany
| | - Anthony S Zannas
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany.,Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, 27710, USA.,Department of Psychiatry, University of North Carolina at Chapel Hill, 438 Taylor Hall, 109 Mason Farm Road, Chapel Hill, 27599-7096, NC, USA.,Department of Genetics, University of North Carolina at Chapel Hil, Chapel Hill, 27599, NC, USA
| | - Alexander Herrmann
- HIV-Cell-Interactions Group, Institute of Virology, German Research Center for Environmental Health, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Florian Holsboer
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany
| | - Ruth Brack-Werner
- HIV-Cell-Interactions Group, Institute of Virology, German Research Center for Environmental Health, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Michael Boshart
- Faculty of Biology, Genetics, Ludwig-Maximilian-University Munich (LMU), 82152, Martinsried, Germany
| | - Bertram Müller-Myhsok
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany.,Institute of Translational Medicine, University of Liverpool, L69 3BX, Liverpool, UK.,Munich Cluster for Systems Neurology - SYNERGY, Feodor-Lynen-Str. 17, 81377, Munich, Germany
| | - Christian Drosten
- Institute of Virology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany
| | - Marcel A Müller
- Institute of Virology, Charité-Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.,German Centre for Infection Research (DZIF), Berlin, Germany.,Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, Sechenov University, 2-4 Bolshaya Pirogovskaya st., 119991, Moscow, Russia
| | - Theo Rein
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstr. 10, 80804, Munich, Germany. .,Faculty of Medicine, Physiological Chemistry, Ludwig-Maximilian-University Munich (LMU), 82152, Martinsried, Germany.
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68
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Inhibition of ULK1 and Beclin1 by an α-herpesvirus Akt-like Ser/Thr kinase limits autophagy to stimulate virus replication. Proc Natl Acad Sci U S A 2019; 116:26941-26950. [PMID: 31843932 DOI: 10.1073/pnas.1915139116] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Autophagy is a powerful host defense that restricts herpes simplex virus-1 (HSV-1) pathogenesis in neurons. As a countermeasure, the viral ICP34.5 polypeptide, which is exclusively encoded by HSV, antagonizes autophagy in part through binding Beclin1. However, whether autophagy is a cell-type-specific antiviral defense or broadly restricts HSV-1 reproduction in nonneuronal cells is unknown. Here, we establish that autophagy limits HSV-1 productive growth in nonneuronal cells and is repressed by the Us3 gene product. Phosphorylation of the autophagy regulators ULK1 and Beclin1 in virus-infected cells was dependent upon the HSV-1 Us3 Ser/Thr kinase. Furthermore, Beclin1 was unexpectedly identified as a direct Us3 kinase substrate. Although disabling autophagy did not impact replication of an ICP34.5-deficient virus in primary human fibroblasts, depleting Beclin1 and ULK1 partially rescued Us3-deficient HSV-1 replication. This shows that autophagy restricts HSV-1 reproduction in a cell-intrinsic manner in nonneuronal cells and is suppressed by multiple, independent viral functions targeting Beclin1 and ULK1. Moreover, it defines a surprising role regulating autophagy for the Us3 kinase, which unlike ICP34.5 is widely encoded by alpha-herpesvirus subfamily members.
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69
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Abstract
Autophagy is an intracellular recycling process that maintains cellular homeostasis by orchestrating immunity upon viral infection. Following viral infection, autophagy is often initiated to curtail infection by delivering viral particles for lysosomal degradation and further integrating with innate pattern recognition receptor signaling to induce interferon (IFN)-mediated viral clearance. However, some viruses have evolved anti-autophagy strategies to escape host immunity and to promote viral replication. In this chapter, we illustrate how autophagy prevents viral infection to generate an optimal anti-viral milieu, and then concentrate on how viruses subvert and hijack the autophagic process to evade immunosurveillance, thereby facilitating viral replication and pathogenesis. Understanding the interplays between autophagy and viral infection is anticipated to guide the development of effective anti-viral therapeutics to fight against infectious diseases.
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70
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Evasion of autophagy mediated by Rickettsia surface protein OmpB is critical for virulence. Nat Microbiol 2019; 4:2538-2551. [PMID: 31611642 PMCID: PMC6988571 DOI: 10.1038/s41564-019-0583-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 09/10/2019] [Indexed: 01/05/2023]
Abstract
Rickettsia are obligate intracellular bacteria that evade antimicrobial autophagy in the host cell cytosol by unknown mechanisms. Other cytosolic pathogens block different steps of autophagy targeting, including the initial step of polyubiquitin-coat formation. One mechanism of evasion is to mobilize actin to the bacterial surface. Here, we show that actin mobilization is insufficient to block autophagy recognition of the pathogen Rickettsia parkeri. Instead, R. parkeri employs outer membrane protein B (OmpB) to block ubiquitylation of the bacterial surface proteins, including OmpA, and subsequent recognition by autophagy receptors. OmpB is also required for the formation of a capsule-like layer. Although OmpB is dispensable for bacterial growth in endothelial cells, it is essential for R. parkeri to block autophagy in macrophages and to colonize mice because of its ability to promote autophagy evasion in immune cells. Our results indicate that OmpB acts as a protective shield to obstruct autophagy recognition, thereby revealing a distinctive bacterial mechanism to evade antimicrobial autophagy.
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71
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Abstract
Autophagy is a powerful tool that host cells use to defend against viral infection. Double-membrane vesicles, termed autophagosomes, deliver trapped viral cargo to the lysosome for degradation. Specifically, autophagy initiates an innate immune response by cooperating with pattern recognition receptor signalling to induce interferon production. It also selectively degrades immune components associated with viral particles. Following degradation, autophagy coordinates adaptive immunity by delivering virus-derived antigens for presentation to T lymphocytes. However, in an ongoing evolutionary arms race, viruses have acquired the potent ability to hijack and subvert autophagy for their benefit. In this Review, we focus on the key regulatory steps during viral infection in which autophagy is involved and discuss the specific molecular mechanisms that diverse viruses use to repurpose autophagy for their life cycle and pathogenesis. Autophagy is crucial for innate and adaptive antiviral immunity; in turn, viruses evade and subvert autophagy to support their replication and pathogenesis. In this Review, Choi, Bowman and Jung discuss the molecular mechanisms that govern autophagy during host–virus interactions.
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72
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Ávila-Pérez G, Diaz-Beneitez E, Cubas-Gaona LL, Nieves-Molina G, Rodríguez JR, Rodríguez JF, Rodríguez D. Activation of the autophagy pathway by Torovirus infection is irrelevant for virus replication. PLoS One 2019; 14:e0219428. [PMID: 31306441 PMCID: PMC6629058 DOI: 10.1371/journal.pone.0219428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 06/24/2019] [Indexed: 11/19/2022] Open
Abstract
Autophagy is a conserved eukaryotic process that mediates lysosomal degradation of cytoplasmic macromolecules and damaged organelles, also exerting an important role in the elimination of intracellular pathogens. Despite the antiviral role of autophagy, many studies suggest that some positive-stranded RNA viruses exploit this pathway to facilitate their own replication. In this study, we demonstrate that the equine torovirus Berne virus (BEV), the prototype member of the Torovirus genus (Coronaviridae Family, Nidovirales Order), induces autophagy at late times post-infection. Conversion of microtubule associated protein 1B light chain 3 (LC3) from cytosolic (LC3 I) to the membrane associated form (LC3 II), a canonical marker of autophagosome formation, is enhanced in BEV infected cells. However, neither autophagy induction, via starvation, nor pharmacological blockade significantly affect BEV replication. Similarly, BEV infection is not altered in autophagy deficient cells lacking either Beclin 1 or LC3B protein expression. Unexpectedly, the cargo receptor p62, a selective autophagy receptor, aggregates within the region where the BEV main protease (Mpro) localizes. This finding, coupled with observation that BEV replication also induces ER stress at the time when selective autophagy is taking place, suggests that the autophagy pathway is activated in response to the hefty accumulation of virus-encoded polypeptides during the late phase of BEV infection.
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Affiliation(s)
- Ginés Ávila-Pérez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin, Madrid, Spain
| | - Elisabet Diaz-Beneitez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin, Madrid, Spain
| | - Liliana L. Cubas-Gaona
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin, Madrid, Spain
| | - Gliselle Nieves-Molina
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin, Madrid, Spain
| | | | - José F. Rodríguez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin, Madrid, Spain
| | - Dolores Rodríguez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin, Madrid, Spain
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73
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Abstract
Human coronavirus (HCoV) infection causes respiratory diseases with mild to severe outcomes. In the last 15 years, we have witnessed the emergence of two zoonotic, highly pathogenic HCoVs: severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Replication of HCoV is regulated by a diversity of host factors and induces drastic alterations in cellular structure and physiology. Activation of critical signaling pathways during HCoV infection modulates the induction of antiviral immune response and contributes to the pathogenesis of HCoV. Recent studies have begun to reveal some fundamental aspects of the intricate HCoV-host interaction in mechanistic detail. In this review, we summarize the current knowledge of host factors co-opted and signaling pathways activated during HCoV infection, with an emphasis on HCoV-infection-induced stress response, autophagy, apoptosis, and innate immunity. The cross talk among these pathways, as well as the modulatory strategies utilized by HCoV, is also discussed.
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Affiliation(s)
- To Sing Fung
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control and Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, Guangdong, People's Republic of China;
| | - Ding Xiang Liu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control and Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, Guangdong, People's Republic of China;
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74
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Abstract
Coronaviruses are pathogens with a serious impact on human and animal health. They mostly cause enteric or respiratory disease, which can be severe and life threatening, e.g., in the case of the zoonotic coronaviruses causing severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS) in humans. Despite the economic and societal impact of such coronavirus infections, and the likelihood of future outbreaks of additional pathogenic coronaviruses, our options to prevent or treat coronavirus infections remain very limited. This highlights the importance of advancing our knowledge on the replication of these viruses and their interactions with the host. Compared to other +RNA viruses, coronaviruses have an exceptionally large genome and employ a complex genome expression strategy. Next to a role in basic virus replication or virus assembly, many of the coronavirus proteins expressed in the infected cell contribute to the coronavirus-host interplay. For example, by interacting with the host cell to create an optimal environment for coronavirus replication, by altering host gene expression or by counteracting the host’s antiviral defenses. These coronavirus–host interactions are key to viral pathogenesis and will ultimately determine the outcome of infection. Due to the complexity of the coronavirus proteome and replication cycle, our knowledge of host factors involved in coronavirus replication is still in an early stage compared to what is known for some other +RNA viruses. This review summarizes our current understanding of coronavirus–host interactions at the level of the infected cell, with special attention for the assembly and function of the viral RNA-synthesising machinery and the evasion of cellular innate immune responses.
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75
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Qin P, Du EZ, Luo WT, Yang YL, Zhang YQ, Wang B, Huang YW. Characteristics of the Life Cycle of Porcine Deltacoronavirus (PDCoV) In Vitro: Replication Kinetics, Cellular Ultrastructure and Virion Morphology, and Evidence of Inducing Autophagy. Viruses 2019; 11:v11050455. [PMID: 31109068 PMCID: PMC6563515 DOI: 10.3390/v11050455] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/15/2019] [Accepted: 05/16/2019] [Indexed: 12/16/2022] Open
Abstract
Porcine deltacoronavirus (PDCoV) causes severe diarrhea and vomiting in affected piglets. The aim of this study was to establish the basic, in vitro characteristics of the life cycle such as replication kinetics, cellular ultrastructure, virion morphology, and induction of autophagy of PDCoV. Time-course analysis of viral subgenomic and genomic RNA loads and infectious titers indicated that one replication cycle of PDCoV takes 5 to 6 h. Electron microscopy showed that PDCoV infection induced the membrane rearrangements with double-membrane vesicles and large virion-containing vacuoles. The convoluted membranes structures described in alpha- and beta-coronavirus were not observed. PDCoV infection also increased the number of autophagosome-like vesicles in the cytoplasm of cells, and the autophagy response was detected by LC3 I/II and p62 Western blot analysis. For the first time, this study presents the picture of the PDCoV infection cycle, which is crucial to help elucidate the molecular mechanism of deltacoronavirus replication.
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Affiliation(s)
- Pan Qin
- Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
| | - En-Zhong Du
- Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
- YEBIO Bioengineering Co., Ltd. of Qingdao, Qingdao 266114, China.
| | - Wen-Ting Luo
- Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Yong-Le Yang
- Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Yu-Qi Zhang
- Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Bin Wang
- Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Yao-Wei Huang
- Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
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76
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Fung TS, Liu DX. The ER stress sensor IRE1 and MAP kinase ERK modulate autophagy induction in cells infected with coronavirus infectious bronchitis virus. Virology 2019; 533:34-44. [PMID: 31082732 PMCID: PMC7112053 DOI: 10.1016/j.virol.2019.05.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/01/2019] [Accepted: 05/01/2019] [Indexed: 12/11/2022]
Abstract
Coronavirus infection induces the generation of autophagosomes, and certain host proteins regulating cellular autophagy are hijacked by some coronaviruses to facilitate the formation of double membrane vesicles. However, mechanisms underlying coronavirus-induced autophagy remain largely unknown. In this study, we demonstrate that autophagosome formation and apparent autophagic flux are induced in cells infected with infectious bronchitis virus (IBV) - a gammacoronavirus. Notably, IBV-induced autophagy was dependent on autophagy related 5 (ATG5) but not beclin1 (BECN1), although both are essential proteins in the canonical autophagy pathway. Moreover, the ER stress sensor inositol requiring enzyme 1 (IRE1), but not its substrate X-box protein 1 (XBP1), was also essential for the induction of autophagy during IBV infection. Finally, the anti-apoptotic extracellular signal-regulated kinase 1/2 (ERK1/2) also contributed to IBV-induced autophagy. Our findings add new knowledge to the regulatory mechanisms governing coronavirus-induced autophagy, highlighting an extensive cross-talk among cellular signaling pathways during coronavirus infection.
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Affiliation(s)
- To Sing Fung
- South China Agricultural University, Guangdong Province Key Laboratory Microbial Signals & Disease Co, and Integrative Microbiology Research Centre, Guangzhou, 510642, Guangdong, People's Republic of China
| | - Ding Xiang Liu
- South China Agricultural University, Guangdong Province Key Laboratory Microbial Signals & Disease Co, and Integrative Microbiology Research Centre, Guangzhou, 510642, Guangdong, People's Republic of China.
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77
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J Alsaadi EA, Jones IM. Membrane binding proteins of coronaviruses. Future Virol 2019; 14:275-286. [PMID: 32201500 PMCID: PMC7079996 DOI: 10.2217/fvl-2018-0144] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 02/19/2019] [Indexed: 12/12/2022]
Abstract
Coronaviruses (CoVs) infect many species causing a variety of diseases with a range of severities. Their members include zoonotic viruses with pandemic potential where therapeutic options are currently limited. Despite this diversity CoVs share some common features including the production, in infected cells, of elaborate membrane structures. Membranes represent both an obstacle and aid to CoV replication - and in consequence - virus-encoded structural and nonstructural proteins have membrane-binding properties. The structural proteins encounter cellular membranes at both entry and exit of the virus while the nonstructural proteins reorganize cellular membranes to benefit virus replication. Here, the role of each protein in membrane binding is described to provide a comprehensive picture of their role in the CoV replication cycle.
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Affiliation(s)
- Entedar A J Alsaadi
- Biomedical Sciences, School of Biological Sciences, University of Reading, Reading RG6 6AJ, UK.,Department of Microbiology, College of Medicine, Thiqar University, Thiqar, Iraq.,Biomedical Sciences, School of Biological Sciences, University of Reading, Reading RG6 6AJ, UK.,Department of Microbiology, College of Medicine, Thiqar University, Thiqar, Iraq
| | - Ian M Jones
- Biomedical Sciences, School of Biological Sciences, University of Reading, Reading RG6 6AJ, UK.,Biomedical Sciences, School of Biological Sciences, University of Reading, Reading RG6 6AJ, UK
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78
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Atg5 Supports Rickettsia australis Infection in Macrophages In Vitro and In Vivo. Infect Immun 2018; 87:IAI.00651-18. [PMID: 30297526 PMCID: PMC6300621 DOI: 10.1128/iai.00651-18] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 09/28/2018] [Indexed: 01/26/2023] Open
Abstract
Rickettsiae can cause life-threatening infections in humans. Macrophages are one of the initial targets for rickettsiae after inoculation by ticks. However, it remains poorly understood how rickettsiae remain free in macrophages prior to establishing their infection in microvascular endothelial cells. Here, we demonstrated that the concentration of Rickettsia australis was significantly greater in infected tissues of Atg5flox/flox mice than in the counterparts of Atg5flox/flox Lyz-Cre mice, in association with a reduced level of interleukin-1β (IL-1β) in serum. The greater concentration of R. australis in Atg5flox/flox bone marrow-derived macrophages (BMMs) than in Atg5flox/flox Lyz-Cre BMMs in vitro was abolished by exogenous treatment with recombinant IL-1β. Rickettsia australis induced significantly increased levels of light chain 3 (LC3) form II (LC3-II) and LC3 puncta in Atg5-competent BMMs but not in Atg5-deficient BMMs, while no p62 turnover was observed. Further analysis found the colocalization of LC3 with a small portion of R. australis and Rickettsia-containing double-membrane-bound vacuoles in the BMMs of B6 mice. Moreover, treatment with rapamycin significantly increased the concentrations of R. australis in B6 BMMs compared to those in the untreated B6 BMM controls. Taken together, our results demonstrate that Atg5 favors R. australis infection in mouse macrophages in association with a suppressed level of IL-1β production but not active autophagy flux. These data highlight the contribution of Atg5 in macrophages to the pathogenesis of rickettsial diseases.
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79
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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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80
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NADPH Oxidase and Guanylate Binding Protein 5 Restrict Survival of Avirulent Type III Strains of Toxoplasma gondii in Naive Macrophages. mBio 2018; 9:mBio.01393-18. [PMID: 30154263 PMCID: PMC6113620 DOI: 10.1128/mbio.01393-18] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Toxoplasma infections in humans and other mammals are largely controlled by IFN-γ produced by the activated adaptive immune system. However, we still do not completely understand the role of cell-intrinsic functions in controlling Toxoplasma or other apicomplexan infections. The present work identifies intrinsic activities in naive macrophages in counteracting T. gondii infection. Using an avirulent strain of T. gondii, we highlight the importance of Nox complexes in conferring protection against parasite infection both in vitro and in vivo. We also identify Gbp5 as a novel macrophage factor involved in limiting intracellular infection by avirulent strains of T. gondii. The rarity of human infections caused by type III strains suggests that these mechanisms may also be important in controlling human toxoplasmosis. These findings further extend our understanding of host responses and defense mechanisms that act to control parasitic infections at the cellular level. Phagocytic cells are the first line of innate defense against intracellular pathogens, and yet Toxoplasma gondii is renowned for its ability to survive in macrophages, although this paradigm is based on virulent type I parasites. Surprisingly, we find that avirulent type III parasites are preferentially cleared in naive macrophages, independent of gamma interferon (IFN-γ) activation. The ability of naive macrophages to clear type III parasites was dependent on enhanced activity of NADPH oxidase (Nox)-generated reactive oxygen species (ROS) and induction of guanylate binding protein 5 (Gbp5). Macrophages infected with type III parasites (CTG strain) showed a time-dependent increase in intracellular ROS generation that was higher than that induced by type I parasites (GT1 strain). The absence of Nox1 or Nox2, gp91 subunit isoforms of the Nox complex, reversed ROS-mediated clearance of CTG parasites. Consistent with this finding, both Nox1−/− and Nox2−/− mice showed higher susceptibility to CTG infection than wild-type mice. Additionally, Gbp5 expression was induced upon infection and the enhanced clearance of CTG strain parasites was reversed in Gbp5−/− macrophages. Expression of a type I ROP18 allele in CTG prevented clearance in naive macrophages, suggesting that it plays a role counteracting Gbp5. Although ROS and Gbp5 have been linked to activation of the NLRP3 inflammasome, clearance of CTG parasites did not rely on induction of pyroptosis. Collectively, these findings reveal that not all strains of T. gondii are adept at avoiding clearance in macrophages and define new roles for ROS and Gbps in controlling this important intracellular pathogen.
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81
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Müller C, Hardt M, Schwudke D, Neuman BW, Pleschka S, Ziebuhr J. Inhibition of Cytosolic Phospholipase A 2α Impairs an Early Step of Coronavirus Replication in Cell Culture. J Virol 2018; 92:e01463-17. [PMID: 29167338 PMCID: PMC5790932 DOI: 10.1128/jvi.01463-17] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 11/14/2017] [Indexed: 12/15/2022] Open
Abstract
Coronavirus replication is associated with intracellular membrane rearrangements in infected cells, resulting in the formation of double-membrane vesicles (DMVs) and other membranous structures that are referred to as replicative organelles (ROs). The latter provide a structural scaffold for viral replication/transcription complexes (RTCs) and help to sequester RTC components from recognition by cellular factors involved in antiviral host responses. There is increasing evidence that plus-strand RNA (+RNA) virus replication, including RO formation and virion morphogenesis, affects cellular lipid metabolism and critically depends on enzymes involved in lipid synthesis and processing. Here, we investigated the role of cytosolic phospholipase A2α (cPLA2α) in coronavirus replication using a low-molecular-weight nonpeptidic inhibitor, pyrrolidine-2 (Py-2). The inhibition of cPLA2α activity, which produces lysophospholipids (LPLs) by cleaving at the sn-2 position of phospholipids, had profound effects on viral RNA and protein accumulation in human coronavirus 229E-infected Huh-7 cells. Transmission electron microscopy revealed that DMV formation in infected cells was significantly reduced in the presence of the inhibitor. Furthermore, we found that (i) viral RTCs colocalized with LPL-containing membranes, (ii) cellular LPL concentrations were increased in coronavirus-infected cells, and (iii) this increase was diminished in the presence of the cPLA2α inhibitor Py-2. Py-2 also displayed antiviral activities against other viruses representing the Coronaviridae and Togaviridae families, while members of the Picornaviridae were not affected. Taken together, the study provides evidence that cPLA2α activity is critically involved in the replication of various +RNA virus families and may thus represent a candidate target for broad-spectrum antiviral drug development.IMPORTANCE Examples of highly conserved RNA virus proteins that qualify as drug targets for broad-spectrum antivirals remain scarce, resulting in increased efforts to identify and specifically inhibit cellular functions that are essential for the replication of RNA viruses belonging to different genera and families. The present study supports and extends previous conclusions that enzymes involved in cellular lipid metabolism may be tractable targets for broad-spectrum antivirals. We obtained evidence to show that a cellular phospholipase, cPLA2α, which releases fatty acid from the sn-2 position of membrane-associated glycerophospholipids, is critically involved in coronavirus replication, most likely by producing lysophospholipids that are required to form the specialized membrane compartments in which viral RNA synthesis takes place. The importance of this enzyme in coronavirus replication and DMV formation is supported by several lines of evidence, including confocal and electron microscopy, viral replication, and lipidomics studies of coronavirus-infected cells treated with a highly specific cPLA2α inhibitor.
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Affiliation(s)
- Christin Müller
- Institute of Medical Virology, Justus Liebig University Giessen, Giessen, Germany
| | - Martin Hardt
- Imaging Unit, Biomedical Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Dominik Schwudke
- Division of Bioanalytical Chemistry, Priority Area Infection, Research Center Borstel, Leibniz Center for Medicine and Bioscience, Borstel, Germany
| | | | - Stephan Pleschka
- Institute of Medical Virology, Justus Liebig University Giessen, Giessen, Germany
| | - John Ziebuhr
- Institute of Medical Virology, Justus Liebig University Giessen, Giessen, Germany
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82
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Ko S, Gu MJ, Kim CG, Kye YC, Lim Y, Lee JE, Park BC, Chu H, Han SH, Yun CH. Rapamycin-induced autophagy restricts porcine epidemic diarrhea virus infectivity in porcine intestinal epithelial cells. Antiviral Res 2017; 146:86-95. [PMID: 28842266 PMCID: PMC7113733 DOI: 10.1016/j.antiviral.2017.08.010] [Citation(s) in RCA: 49] [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: 09/23/2016] [Revised: 07/16/2017] [Accepted: 08/15/2017] [Indexed: 12/22/2022]
Abstract
Porcine epidemic diarrhea virus (PEDV) invades porcine intestinal epithelial cells (IECs) and causes diarrhea and dehydration in pigs. In the present study, we showed a suppression of PEDV infection in porcine jejunum intestinal epithelial cells (IPEC-J2) by an increase in autophagy. Autophagy was activated by rapamycin at a dose that does not affect cell viability and tight junction permeability. The induction of autophagy was examined by LC3I/LC3II conversion. To confirm the autophagic-flux (entire autophagy pathway), autophagolysosomes were examined by an immunofluorescence assay. Pre-treatment with rapamycin significantly restricted not only a 1 h infection but also a longer infection (24 h) with PEDV, while this effect disappeared when autophagy was blocked. Co-localization of PEDV and autophagosomes suggests that PEDV could be a target of autophagy. Moreover, alleviation of PEDV-induced cell death in IPEC-J2 cells pretreated with rapamycin demonstrates a protective effect of rapamycin against PEDV-induced epithelial cell death. Collectively, the present study suggests an early prevention against PEDV infection in IPEC-J2 cells via autophagy that might be an effective strategy for the restriction of PEDV, and opens up the possibility of the use of rapamycin in vivo as an effective prophylactic and prevention treatment. Rapamycin has an antiviral effect against PEDV infection. Rapamycin prevents PEDV-induced cell death. Rapamycin-induced autophagy restricted PEDV infection in porcine intestinal epithelial cells.
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Affiliation(s)
- Seongyeol Ko
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Min Jeong Gu
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Cheol Gyun Kim
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Yoon Chul Kye
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Younggap Lim
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Ji Eun Lee
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Byung-Chul Park
- Institute of Green Bio Science Technology, Seoul National University, Pyeongchang 23254, Republic of Korea
| | - Hyuk Chu
- Division of Zoonoses, Center for Immunology and Pathology, National Institute of Health, Korea Centers for Disease Control and Prevention, Osong 28159, Republic of Korea
| | - Seung Hyun Han
- Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Cheol-Heui Yun
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea; Institute of Green Bio Science Technology, Seoul National University, Pyeongchang 23254, Republic of Korea.
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83
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Cong Y, Verlhac P, Reggiori F. The Interaction between Nidovirales and Autophagy Components. Viruses 2017; 9:E182. [PMID: 28696396 PMCID: PMC5537674 DOI: 10.3390/v9070182] [Citation(s) in RCA: 26] [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: 06/15/2017] [Revised: 06/28/2017] [Accepted: 07/03/2017] [Indexed: 12/15/2022] Open
Abstract
Autophagy is a conserved intracellular catabolic pathway that allows cells to maintain homeostasis through the degradation of deleterious components via specialized double-membrane vesicles called autophagosomes. During the past decades, it has been revealed that numerous pathogens, including viruses, usurp autophagy in order to promote their propagation. Nidovirales are an order of enveloped viruses with large single-stranded positive RNA genomes. Four virus families (Arterividae, Coronaviridae, Mesoniviridae, and Roniviridae) are part of this order, which comprises several human and animal pathogens of medical and veterinary importance. In host cells, Nidovirales induce membrane rearrangements including autophagosome formation. The relevance and putative mechanism of autophagy usurpation, however, remain largely elusive. Here, we review the current knowledge about the possible interplay between Nidovirales and autophagy.
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Affiliation(s)
- Yingying Cong
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
| | - Pauline Verlhac
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
| | - Fulvio Reggiori
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
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84
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Solvik T, Debnath J. At the crossroads of autophagy and infection: Noncanonical roles for ATG proteins in viral replication. J Cell Biol 2017; 214:503-5. [PMID: 27573461 PMCID: PMC5004452 DOI: 10.1083/jcb.201608032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 08/08/2016] [Indexed: 11/23/2022] Open
Abstract
Autophagy-related (ATG) proteins have increasingly demonstrated functions other than cellular self-eating. In this issue, Mauthe et al. (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201602046) conduct an unbiased RNA interference screen of the ATG proteome to reveal numerous noncanonical roles for ATG proteins during viral infection.
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Affiliation(s)
- Tina Solvik
- Department of Pathology, University of California, San Francisco, San Francisco, CA 94143 Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143 Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Jayanta Debnath
- Department of Pathology, University of California, San Francisco, San Francisco, CA 94143 Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
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85
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Porcine Epidemic Diarrhea Virus Induces Autophagy to Benefit Its Replication. Viruses 2017; 9:v9030053. [PMID: 28335505 PMCID: PMC5371808 DOI: 10.3390/v9030053] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/13/2017] [Accepted: 03/15/2017] [Indexed: 02/06/2023] Open
Abstract
The new porcine epidemic diarrhea (PED) has caused devastating economic losses to the swine industry worldwide. Despite extensive research on the relationship between autophagy and virus infection, the concrete role of autophagy in porcine epidemic diarrhea virus (PEDV) infection has not been reported. In this study, autophagy was demonstrated to be triggered by the effective replication of PEDV through transmission electron microscopy, confocal microscopy, and Western blot analysis. Moreover, autophagy was confirmed to benefit PEDV replication by using autophagy regulators and RNA interference. Furthermore, autophagy might be associated with the expression of inflammatory cytokines and have a positive feedback loop with the NF-κB signaling pathway during PEDV infection. This work is the first attempt to explore the complex interplay between autophagy and PEDV infection. Our findings might accelerate our understanding of the pathogenesis of PEDV infection and provide new insights into the development of effective therapeutic strategies.
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86
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Chinchwadkar S, Padmanabhan S, Mishra P, Singh S, Suresh SN, Vats S, Barve G, Ammanathan V, Manjithaya R. Multifaceted Housekeeping Functions of Autophagy. J Indian Inst Sci 2017. [DOI: 10.1007/s41745-016-0015-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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87
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Jessop F, Hamilton RF, Rhoderick JF, Shaw PK, Holian A. Autophagy deficiency in macrophages enhances NLRP3 inflammasome activity and chronic lung disease following silica exposure. Toxicol Appl Pharmacol 2016; 309:101-10. [PMID: 27594529 DOI: 10.1016/j.taap.2016.08.029] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 08/20/2016] [Accepted: 08/30/2016] [Indexed: 01/12/2023]
Abstract
Autophagy is an important metabolic mechanism that can promote cellular survival following injury. The specific contribution of autophagy to silica-induced inflammation and disease is not known. The objective of these studies was to determine the effects of silica exposure on the autophagic pathway in macrophages, as well as the general contribution of autophagy in macrophages to inflammation and disease. Silica exposure enhanced autophagic activity in vitro in Bone Marrow derived Macrophages and in vivo in Alveolar Macrophages isolated from silica-exposed mice. Impairment of autophagy in myeloid cells in vivo using Atg5(fl/fl)LysM-Cre(+) mice resulted in enhanced cytotoxicity and inflammation after silica exposure compared to littermate controls, including elevated IL-18 and the alarmin HMGB1 in the whole lavage fluid. Autophagy deficiency caused some spontaneous inflammation and disease. Greater silica-induced acute inflammation in Atg5(fl/fl)LysM-Cre(+) mice correlated with increased fibrosis and chronic lung disease. These studies demonstrate a critical role for autophagy in suppressing silica-induced cytotoxicity and inflammation in disease development. Furthermore, this data highlights the importance of basal autophagy in macrophages and other myeloid cells in maintaining lung homeostasis.
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Affiliation(s)
- Forrest Jessop
- Center for Environmental Health Sciences, University of Montana, Missoula, Montana, United States
| | - Raymond F Hamilton
- Center for Environmental Health Sciences, University of Montana, Missoula, Montana, United States
| | - Joseph F Rhoderick
- Center for Environmental Health Sciences, University of Montana, Missoula, Montana, United States
| | - Pamela K Shaw
- Center for Environmental Health Sciences, University of Montana, Missoula, Montana, United States
| | - Andrij Holian
- Center for Environmental Health Sciences, University of Montana, Missoula, Montana, United States.
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88
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Mauthe M, Langereis M, Jung J, Zhou X, Jones A, Omta W, Tooze SA, Stork B, Paludan SR, Ahola T, Egan D, Behrends C, Mokry M, de Haan C, van Kuppeveld F, Reggiori F. An siRNA screen for ATG protein depletion reveals the extent of the unconventional functions of the autophagy proteome in virus replication. J Cell Biol 2016; 214:619-35. [PMID: 27573464 PMCID: PMC5004442 DOI: 10.1083/jcb.201602046] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 07/25/2016] [Indexed: 02/06/2023] Open
Abstract
Autophagy is a catabolic process regulated by the orchestrated action of the autophagy-related (ATG) proteins. Recent work indicates that some of the ATG proteins also have autophagy-independent roles. Using an unbiased siRNA screen approach, we explored the extent of these unconventional functions of ATG proteins. We determined the effects of the depletion of each ATG proteome component on the replication of six different viruses. Our screen reveals that up to 36% of the ATG proteins significantly alter the replication of at least one virus in an unconventional fashion. Detailed analysis of two candidates revealed an undocumented role for ATG13 and FIP200 in picornavirus replication that is independent of their function in autophagy as part of the ULK complex. The high numbers of unveiled ATG gene-specific and pathogen-specific functions of the ATG proteins calls for caution in the interpretation of data, which rely solely on the depletion of a single ATG protein to specifically ablate autophagy.
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Affiliation(s)
- Mario Mauthe
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 AV Groningen, Netherlands Department of Cell Biology, University Medical Center Utrecht, 3584 CX Utrecht, Netherlands
| | - Martijn Langereis
- Virology Division, Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, 3584 CL Utrecht, Netherlands
| | - Jennifer Jung
- Institute of Biochemistry II, Goethe University School of Medicine, 60590 Frankfurt am Main, Germany
| | - Xingdong Zhou
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 AV Groningen, Netherlands Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150030, People's Republic of China
| | - Alex Jones
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 AV Groningen, Netherlands Department of Cell Biology, University Medical Center Utrecht, 3584 CX Utrecht, Netherlands
| | - Wienand Omta
- Department of Cell Biology, University Medical Center Utrecht, 3584 CX Utrecht, Netherlands
| | - Sharon A Tooze
- Lincoln's Inn Fields Laboratories, The Francis Crick Institute, London WC2A 3LY, England, UK
| | - Björn Stork
- Institute of Molecular Medicine I, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | | | - Tero Ahola
- Department of Food and Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland
| | - Dave Egan
- Department of Cell Biology, University Medical Center Utrecht, 3584 CX Utrecht, Netherlands
| | - Christian Behrends
- Institute of Biochemistry II, Goethe University School of Medicine, 60590 Frankfurt am Main, Germany
| | - Michal Mokry
- Regenerative Medicine Center Utrecht, Center for Molecular Medicine, University Medical Center Utrecht, 3584 CX Utrecht, Netherlands Division of Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, 3584 EA Utrecht, Netherlands
| | - Cornelis de Haan
- Virology Division, Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, 3584 CL Utrecht, Netherlands
| | - Frank van Kuppeveld
- Virology Division, Department of Infectious Diseases and Immunology, Utrecht University, Utrecht, 3584 CL Utrecht, Netherlands
| | - Fulvio Reggiori
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, 9713 AV Groningen, Netherlands Department of Cell Biology, University Medical Center Utrecht, 3584 CX Utrecht, Netherlands
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Lin M, Liu H, Xiong Q, Niu H, Cheng Z, Yamamoto A, Rikihisa Y. Ehrlichia secretes Etf-1 to induce autophagy and capture nutrients for its growth through RAB5 and class III phosphatidylinositol 3-kinase. Autophagy 2016; 12:2145-2166. [PMID: 27541856 PMCID: PMC5103349 DOI: 10.1080/15548627.2016.1217369] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Ehrlichia chaffeensis is an obligatory intracellular bacterium that causes a potentially fatal emerging zoonosis, human monocytic ehrlichiosis. E. chaffeensis has a limited capacity for biosynthesis and metabolism and thus depends mostly on host-synthesized nutrients for growth. Although the host cell cytoplasm is rich with these nutrients, as E. chaffeensis is confined within the early endosome-like membrane-bound compartment, only host nutrients that enter the compartment can be used by this bacterium. How this occurs is unknown. We found that ehrlichial replication depended on autophagy induction involving class III phosphatidylinositol 3-kinase (PtdIns3K) activity, BECN1 (Beclin 1), and ATG5 (autophagy-related 5). Ehrlichia acquired host cell preincorporated amino acids in a class III PtdIns3K-dependent manner and ehrlichial growth was enhanced by treatment with rapamycin, an autophagy inducer. Moreover, ATG5 and RAB5A/B/C were routed to ehrlichial inclusions. RAB5A/B/C siRNA knockdown, or overexpression of a RAB5-specific GTPase-activating protein or dominant-negative RAB5A inhibited ehrlichial infection, indicating the critical role of GTP-bound RAB5 during infection. Both native and ectopically expressed ehrlichial type IV secretion effector protein, Etf-1, bound RAB5 and the autophagy-initiating class III PtdIns3K complex, PIK3C3/VPS34, and BECN1, and homed to ehrlichial inclusions. Ectopically expressed Etf-1 activated class III PtdIns3K as in E. chaffeensis infection and induced autophagosome formation, cleared an aggregation-prone mutant huntingtin protein in a class III PtdIns3K-dependent manner, and enhanced ehrlichial proliferation. These data support the notion that E. chaffeensis secretes Etf-1 to induce autophagy to repurpose the host cytoplasm and capture nutrients for its growth through RAB5 and class III PtdIns3K, while avoiding autolysosomal killing.
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Affiliation(s)
- Mingqun Lin
- a Department of Veterinary Biosciences , Ohio State University , Columbus , OH , USA
| | - Hongyan Liu
- a Department of Veterinary Biosciences , Ohio State University , Columbus , OH , USA
| | - Qingming Xiong
- a Department of Veterinary Biosciences , Ohio State University , Columbus , OH , USA
| | - Hua Niu
- a Department of Veterinary Biosciences , Ohio State University , Columbus , OH , USA
| | - Zhihui Cheng
- a Department of Veterinary Biosciences , Ohio State University , Columbus , OH , USA
| | - Akitsugu Yamamoto
- b Faculty of Bioscience , Nagahama Institute of Bioscience and Technology , Nagahama , Shiga , Japan
| | - Yasuko Rikihisa
- a Department of Veterinary Biosciences , Ohio State University , Columbus , OH , USA
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90
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Role of autophagy in cellular response to infection with Orf virus Jilin isolate. Vet Microbiol 2016; 193:22-7. [PMID: 27599926 DOI: 10.1016/j.vetmic.2016.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Revised: 07/26/2016] [Accepted: 08/03/2016] [Indexed: 12/31/2022]
Abstract
Autophagy is a conserved catabolic process of the cell, which has been described to be involved in the development of various viral diseases. However, the role of autophagy in Orf virus (ORFV) replication remains unknown. In this study, we provide the first evidence that ORFV infection triggered autophagy in primary ovine fetal turbinate cells (OFTu) based on the appearance of abundant double- and single-membrane vesicles, the accumulation of LC3 fluorescent puncta, the enhancement of LC3-I/-II conversion, and autophagic flux. Moreover, modulation of ORFV-induced autophagy by rapamycin (RAPA), Earle's balanced salts solution (EBSS), chloroquine (CQ) or 3-methyladenime (3-MA) does not affect virus production. In conclusion, these results suggest that autophagy can be induced in host cells by ORFV infection, but which maybe not essential for ORFV replication.
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91
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Ávila-Pérez G, Rejas MT, Rodríguez D. Ultrastructural characterization of membranous torovirus replication factories. Cell Microbiol 2016; 18:1691-1708. [PMID: 27218226 PMCID: PMC7162420 DOI: 10.1111/cmi.12620] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/27/2016] [Accepted: 05/19/2016] [Indexed: 12/24/2022]
Abstract
Plus‐stranded RNA viruses replicate in the cytosol of infected cells, in membrane‐bound replication complexes containing the replicase proteins, the viral RNA and host proteins. The formation of the replication and transcription complexes (RTCs) through the rearrangement of cellular membranes is currently being actively studied for viruses belonging to different viral families. In this work, we identified double‐membrane vesicles (DMVs) in the cytoplasm of cells infected with the equine torovirus Berne virus (BEV), the prototype member of the Torovirus genus (Coronaviridae family, Nidovirales order). Using confocal microscopy and transmission electron microscopy, we observed a close relationship between the RTCs and the DMVs of BEV. The examination of BEV‐infected cells revealed that the replicase proteins colocalize with each other and with newly synthesized RNA and are associated to the membrane rearrangement induced by BEV. However, the double‐stranded RNA, an intermediate of viral replication, is exclusively limited to the interior of DMVs. Our results with BEV resemble those obtained with other related viruses in the Nidovirales order, thus providing new evidence to support the idea that nidoviruses share a common replicative structure based on the DMV arranged clusters.
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Affiliation(s)
- Ginés Ávila-Pérez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin 3, 28049, Madrid, Spain
| | - María Teresa Rejas
- Electron Microscopy Facility, Centro de Biología Molecular Severo Ochoa, CSIC, C/Nicolás Cabrera 1, 28049, Madrid, Spain
| | - Dolores Rodríguez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, CSIC, C/Darwin 3, 28049, Madrid, Spain
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92
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Rockel JS, Kapoor M. Autophagy: controlling cell fate in rheumatic diseases. Nat Rev Rheumatol 2016; 12:517-31. [DOI: 10.1038/nrrheum.2016.92] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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93
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Alirezaei M, Flynn CT, Wood MR, Harkins S, Whitton JL. Coxsackievirus can exploit LC3 in both autophagy-dependent and -independent manners in vivo. Autophagy 2016; 11:1389-407. [PMID: 26090585 DOI: 10.1080/15548627.2015.1063769] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
RNA viruses modify intracellular membranes to produce replication scaffolds. In pancreatic cells, coxsackievirus B3 (CVB3) hijacks membranes from the autophagy pathway, and in vivo disruption of acinar cell autophagy dramatically delays CVB3 replication. This is reversed by expression of GFP-LC3, indicating that CVB3 may acquire membranes from an alternative, autophagy-independent, source(s). Herein, using 3 recombinant CVB3s (rCVB3s) encoding different proteins (proLC3, proLC3(G120A), or ATG4B(C74A)), we show that CVB3 is, indeed, flexible in its utilization of cellular membranes. When compared with a control rCVB3, all 3 viruses replicated to high titers in vivo, and caused severe pancreatitis. Most importantly, each virus appeared to subvert membranes in a unique manner. The proLC3 virus produced a large quantity of LC3-I which binds to phosphatidylethanolamine (PE), affording access to the autophagy pathway. The proLC3(G120A) protein cannot attach to PE, and instead binds to the ER-resident protein SEL1L, potentially providing an autophagy-independent source of membranes. Finally, the ATG4B(C74A) protein sequestered host cell LC3-I, causing accumulation of immature phagophores, and massive membrane rearrangement. Taken together, our data indicate that some RNA viruses can exploit a variety of different intracellular membranes, potentially maximizing their replication in each of the diverse cell types that they infect in vivo.
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Affiliation(s)
- Mehrdad Alirezaei
- a Department of Immunology and Microbial Science; The Scripps Research Institute ; La Jolla , CA USA
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94
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van der Hoeven B, Oudshoorn D, Koster AJ, Snijder EJ, Kikkert M, Bárcena M. Biogenesis and architecture of arterivirus replication organelles. Virus Res 2016; 220:70-90. [PMID: 27071852 PMCID: PMC7111217 DOI: 10.1016/j.virusres.2016.04.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 04/01/2016] [Indexed: 02/06/2023]
Abstract
Arterivirus RNA synthesis presumably is associated with double-membrane vesicles (DMVs). Putative intermediates in DMV formation were detected in infected cells. Arterivirus-induced DMVs form a highly interconnected reticulovesicular network (RVN). Expression of the nsp2-3 replicase polyprotein fragment induces a comparable RVN. Nsp2-7 expression results in smaller DMVs, closer in size to DMVs found in infection.
All eukaryotic positive-stranded RNA (+RNA) viruses appropriate host cell membranes and transform them into replication organelles, specialized micro-environments that are thought to support viral RNA synthesis. Arteriviruses (order Nidovirales) belong to the subset of +RNA viruses that induce double-membrane vesicles (DMVs), similar to the structures induced by e.g. coronaviruses, picornaviruses and hepatitis C virus. In the last years, electron tomography has revealed substantial differences between the structures induced by these different virus groups. Arterivirus-induced DMVs appear to be closed compartments that are continuous with endoplasmic reticulum membranes, thus forming an extensive reticulovesicular network (RVN) of intriguing complexity. This RVN is remarkably similar to that described for the distantly related coronaviruses (also order Nidovirales) and sets them apart from other DMV-inducing viruses analysed to date. We review here the current knowledge and open questions on arterivirus replication organelles and discuss them in the light of the latest studies on other DMV-inducing viruses, particularly coronaviruses. Using the equine arteritis virus (EAV) model system and electron tomography, we present new data regarding the biogenesis of arterivirus-induced DMVs and uncover numerous putative intermediates in DMV formation. We generated cell lines that can be induced to express specific EAV replicase proteins and showed that DMVs induced by the transmembrane proteins nsp2 and nsp3 form an RVN and are comparable in topology and architecture to those formed during viral infection. Co-expression of the third EAV transmembrane protein (nsp5), expressed as part of a self-cleaving polypeptide that mimics viral polyprotein processing in infected cells, led to the formation of DMVs whose size was more homogenous and closer to what is observed upon EAV infection, suggesting a regulatory role for nsp5 in modulating membrane curvature and DMV formation.
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Affiliation(s)
- Barbara van der Hoeven
- Electron Microscopy Section, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Diede Oudshoorn
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Abraham J Koster
- Electron Microscopy Section, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Eric J Snijder
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Marjolein Kikkert
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands.
| | - Montserrat Bárcena
- Electron Microscopy Section, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands.
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95
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Guo L, Yu H, Gu W, Luo X, Li R, Zhang J, Xu Y, Yang L, Shen N, Feng L, Wang Y. Autophagy Negatively Regulates Transmissible Gastroenteritis Virus Replication. Sci Rep 2016; 6:23864. [PMID: 27029407 PMCID: PMC4814908 DOI: 10.1038/srep23864] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 03/15/2016] [Indexed: 12/21/2022] Open
Abstract
Autophagy is an evolutionarily ancient pathway that has been shown to be important in the innate immune defense against several viruses. However, little is known about the regulatory role of autophagy in transmissible gastroenteritis virus (TGEV) replication. In this study, we found that TGEV infection increased the number of autophagosome-like double- and single-membrane vesicles in the cytoplasm of host cells, a phenomenon that is known to be related to autophagy. In addition, virus replication was required for the increased amount of the autophagosome marker protein LC3-II. Autophagic flux occurred in TGEV-infected cells, suggesting that TGEV infection triggered a complete autophagic response. When autophagy was pharmacologically inhibited by wortmannin or LY294002, TGEV replication increased. The increase in virus yield via autophagy inhibition was further confirmed by the use of siRNA duplexes, through which three proteins required for autophagy were depleted. Furthermore, TGEV replication was inhibited when autophagy was activated by rapamycin. The antiviral response of autophagy was confirmed by using siRNA to reduce the expression of gene p300, which otherwise inhibits autophagy. Together, the results indicate that TGEV infection activates autophagy and that autophagy then inhibits further TGEV replication.
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Affiliation(s)
- Longjun Guo
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Haidong Yu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China.,Weike Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Weihong Gu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Xiaolei Luo
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Ren Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Jian Zhang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yunfei Xu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Lijun Yang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Nan Shen
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Li Feng
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yue Wang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
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96
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New Verapamil Analogs Inhibit Intracellular Mycobacteria without Affecting the Functions of Mycobacterium-Specific T Cells. Antimicrob Agents Chemother 2015; 60:1216-25. [PMID: 26643325 DOI: 10.1128/aac.01567-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 11/24/2015] [Indexed: 01/17/2023] Open
Abstract
There is a growing interest in repurposing mycobacterial efflux pump inhibitors, such as verapamil, for tuberculosis (TB) treatment. To aid in the design of better analogs, we studied the effects of verapamil on macrophages and Mycobacterium tuberculosis-specific T cells. Macrophage activation was evaluated by measuring levels of nitric oxide, tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), and gamma interferon (IFN-γ). Since verapamil is a known autophagy inducer, the roles of autophagy induction in the antimycobacterial activities of verapamil and norverapamil were studied using bone marrow-derived macrophages from ATG5(flox/flox) (control) and ATG5(flox/flox) Lyz-Cre mice. Our results showed that despite the well-recognized effects of verapamil on calcium channels and autophagy, its action on intracellular M. tuberculosis does not involve macrophage activation or autophagy induction. Next, the effects of verapamil and norverapamil on M. tuberculosis-specific T cells were assessed using flow cytometry following the stimulation of peripheral blood mononuclear cells from TB-skin-test-positive donors with M. tuberculosis whole-cell lysate for 7 days in the presence or absence of drugs. We found that verapamil and norverapamil inhibit the expansion of M. tuberculosis-specific T cells. Additionally, three new verapamil analogs were found to inhibit intracellular Mycobacterium bovis BCG, and one of the three analogs (KSV21) inhibited intracellular M. tuberculosis replication at concentrations that did not inhibit M. tuberculosis-specific T cell expansion. KSV21 also inhibited mycobacterial efflux pumps to the same degree as verapamil. More interestingly, the new analog enhances the inhibitory activities of isoniazid and rifampin on intracellular M. tuberculosis. In conclusion, KSV21 is a promising verapamil analog on which to base structure-activity relationship studies aimed at identifying more effective analogs.
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97
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Rey-Jurado E, Riedel CA, González PA, Bueno SM, Kalergis AM. Contribution of autophagy to antiviral immunity. FEBS Lett 2015; 589:3461-70. [PMID: 26297829 PMCID: PMC7094639 DOI: 10.1016/j.febslet.2015.07.047] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Revised: 07/20/2015] [Accepted: 07/29/2015] [Indexed: 12/22/2022]
Abstract
Although identified in the 1960's, interest in autophagy has significantly increased in the past decade with notable research efforts oriented at understanding as to how this multi-protein complex operates and is regulated. Autophagy is commonly defined as a "self-eating" process evolved by eukaryotic cells to recycle senescent organelles and expired proteins, which is significantly increased during cellular stress responses. In addition, autophagy can also play important roles during human diseases, such as cancer, neurodegenerative and autoimmune disorders. Furthermore, novel findings suggest that autophagy contributes to the host defense against microbial infections. In this article, we review the role of macroautophagy in antiviral immune responses and discuss molecular mechanisms evolved by viral pathogens to evade this process. A role for autophagy as an effector mechanism used both, by innate and adaptive immunity is also discussed.
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Affiliation(s)
- Emma Rey-Jurado
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Claudia A Riedel
- Millennium Institute on Immunology and Immunotherapy, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas y Facultad de Medicina, Universidad Andrés Bello, Santiago, Chile
| | - Pablo A González
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M Bueno
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexis M Kalergis
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile; Departamento de Inmunología Clínica y Reumatología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; INSERM U1064, Nantes, France.
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98
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Reid CR, Airo AM, Hobman TC. The Virus-Host Interplay: Biogenesis of +RNA Replication Complexes. Viruses 2015; 7:4385-413. [PMID: 26287230 PMCID: PMC4576186 DOI: 10.3390/v7082825] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 07/21/2015] [Accepted: 07/24/2015] [Indexed: 12/22/2022] Open
Abstract
Positive-strand RNA (+RNA) viruses are an important group of human and animal pathogens that have significant global health and economic impacts. Notable members include West Nile virus, Dengue virus, Chikungunya, Severe acute respiratory syndrome (SARS) Coronavirus and enteroviruses of the Picornaviridae family.Unfortunately, prophylactic and therapeutic treatments against these pathogens are limited. +RNA viruses have limited coding capacity and thus rely extensively on host factors for successful infection and propagation. A common feature among these viruses is their ability to dramatically modify cellular membranes to serve as platforms for genome replication and assembly of new virions. These viral replication complexes (VRCs) serve two main functions: To increase replication efficiency by concentrating critical factors and to protect the viral genome from host anti-viral systems. This review summarizes current knowledge of critical host factors recruited to or demonstrated to be involved in the biogenesis and stabilization of +RNA virus VRCs.
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Affiliation(s)
- Colleen R Reid
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2E1, Canada.
| | - Adriana M Airo
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2E1, Canada.
| | - Tom C Hobman
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2E1, Canada.
- Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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99
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The Emerging Roles of Viroporins in ER Stress Response and Autophagy Induction during Virus Infection. Viruses 2015; 7:2834-57. [PMID: 26053926 PMCID: PMC4488716 DOI: 10.3390/v7062749] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 05/27/2015] [Accepted: 05/29/2015] [Indexed: 01/14/2023] Open
Abstract
Viroporins are small hydrophobic viral proteins that oligomerize to form aqueous pores on cellular membranes. Studies in recent years have demonstrated that viroporins serve important functions during virus replication and contribute to viral pathogenicity. A number of viroporins have also been shown to localize to the endoplasmic reticulum (ER) and/or its associated membranous organelles. In fact, replication of most RNA viruses is closely linked to the ER, and has been found to cause ER stress in the infected cells. On the other hand, autophagy is an evolutionarily conserved "self-eating" mechanism that is also observed in cells infected with RNA viruses. Both ER stress and autophagy are also known to modulate a wide variety of signaling pathways including pro-inflammatory and innate immune response, thereby constituting a major aspect of host-virus interactions. In this review, the potential involvement of viroporins in virus-induced ER stress and autophagy will be discussed.
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100
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V'kovski P, Al-Mulla H, Thiel V, Neuman BW. New insights on the role of paired membrane structures in coronavirus replication. Virus Res 2014; 202:33-40. [PMID: 25550072 PMCID: PMC7114427 DOI: 10.1016/j.virusres.2014.12.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 12/16/2014] [Accepted: 12/18/2014] [Indexed: 12/22/2022]
Abstract
Coronavirus replication is tied to formation of double-membrane organelles (DMOs). DMO-making genes are conserved across the Nidovirales. Here, we interpret recent experiments on the role and importance of coronavirus DMOs.
The replication of coronaviruses, as in other positive-strand RNA viruses, is closely tied to the formation of membrane-bound replicative organelles inside infected cells. The proteins responsible for rearranging cellular membranes to form the organelles are conserved not just among the Coronaviridae family members, but across the order Nidovirales. Taken together, these observations suggest that the coronavirus replicative organelle plays an important role in viral replication, perhaps facilitating the production or protection of viral RNA. However, the exact nature of this role, and the specific contexts under which it is important have not been fully elucidated. Here, we collect and interpret the recent experimental evidence about the role and importance of membrane-bound organelles in coronavirus replication.
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Affiliation(s)
- Philip V'kovski
- Federal Institute of Virology and Immunology, Mittelhäusern, Bern, Switzerland; Graduate School for Biomedical Sciences, University of Bern, Switzerland
| | - Hawaa Al-Mulla
- School of Biological Sciences, University of Reading, Reading, Berkshire, United Kingdom; University of Baghdad, College of Science, Baghdad, Iraq
| | - Volker Thiel
- Federal Institute of Virology and Immunology, Mittelhäusern, Bern, Switzerland; Vetsuisse Faculty, University of Bern, Bern, Switzerland.
| | - Benjamin W Neuman
- School of Biological Sciences, University of Reading, Reading, Berkshire, United Kingdom.
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