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Miłogrodzka I, Le Brun AP, Banaszak Holl MM, van 't Hag L. HIV and influenza fusion peptide interactions with (dis)ordered lipid bilayers: Understanding mechanisms and implications for antimicrobial and antiviral approaches. J Colloid Interface Sci 2024; 670:563-575. [PMID: 38776691 DOI: 10.1016/j.jcis.2024.05.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/05/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024]
Abstract
The interactions of viral fusion peptides from influenza (E4K and Ac-E4K) and human immunodeficiency virus (gp41 and Ac-gp41) with planar lipid bilayers and monolayers was investigated herein. A combination of surface-sensitive techniques, including quartz crystal microbalance with dissipation (QCM-D), Langmuir-Blodgett area-pressure isotherms with Micro-Brewster angle microscopy, and neutron reflectometry, was employed. Differences in the interactions of the viral fusion peptides with lipid bilayers featuring ordered and disordered phases, as well as lipid rafts, were revealed. The HIV fusion peptide (gp41) exhibited strong binding to the DOPC/DOPS bilayer, comprising a liquid disordered phase, with neutron reflectometry (NR) showing interaction with the bilayer's headgroup area. Conversely, negligible binding was observed with lipid bilayers in a liquid ordered phase. Notably, the influenza peptide (E4K) demonstrated slower binding kinetics with DOPC/DOPS bilayers and distinct interactions compared to gp41, as observed through QCM-D. This suggests different mechanisms of interaction with the lipid bilayers: one peptide interacts more within the headgroup region, while the other is more involved in transmembrane interactions. These findings hold implications for understanding viral fusion mechanisms and developing antimicrobials and antivirals targeting membrane interactions. The differential binding behaviours of the viral fusion peptides underscore the importance of considering membrane composition and properties in therapeutic strategy design.
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Affiliation(s)
- Izabela Miłogrodzka
- Department of Chemical and Biological Engineering, Monash University, Clayton, Victoria, Australia; Australian Synchrotron, Clayton, Victoria, Australia
| | - Anton P Le Brun
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, Australia
| | - Mark M Banaszak Holl
- Department of Chemical and Biological Engineering, Monash University, Clayton, Victoria, Australia; Department of Mechanical and Materials Engineering, University of Alabama at Birmingham, Birmingham, AL, USA; Division of Pulmonology, Allergy, and Critical Care Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Leonie van 't Hag
- Department of Chemical and Biological Engineering, Monash University, Clayton, Victoria, Australia.
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2
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Schwickert KK, Glitscher M, Bender D, Benz NI, Murra R, Schwickert K, Pfalzgraf S, Schirmeister T, Hellmich UA, Hildt E. Zika virus replication is impaired by a selective agonist of the TRPML2 ion channel. Antiviral Res 2024; 228:105940. [PMID: 38901736 DOI: 10.1016/j.antiviral.2024.105940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 05/21/2024] [Accepted: 06/17/2024] [Indexed: 06/22/2024]
Abstract
The flavivirus genus includes human pathogenic viruses such as Dengue (DENV), West Nile (WNV) and Zika virus (ZIKV) posing a global health threat due to limited treatment options. Host ion channels are crucial for various viral life cycle stages, but their potential as targets for antivirals is often not fully realized due to the lack of selective modulators. Here, we observe that treatment with ML2-SA1, an agonist for the human endolysosomal cation channel TRPML2, impairs ZIKV replication. Upon ML2-SA1 treatment, levels of intracellular genomes and number of released virus particles of two different ZIKV isolates were significantly reduced and cells displayed enlarged vesicular structures and multivesicular bodies with ZIKV envelope protein accumulation. However, no increased ZIKV degradation in lysosomal compartments was observed. Rather, the antiviral effect of ML2-SA1 seemed to manifest by the compound's negative impact on genome replication. Moreover, ML2-SA1 treatment also led to intracellular cholesterol accumulation. ZIKV and many other viruses including the Orthohepevirus Hepatitis E virus (HEV) rely on the endolysosomal system and are affected by intracellular cholesterol levels to complete their life cycle. Since we observed that ML2-SA1 also negatively impacted HEV infections in vitro, this compound may harbor a broader antiviral potential through perturbing the intracellular cholesterol distribution. Besides indicating that TRPML2 may be a promising target for combatting viral infections, we uncover a tentative connection between this protein and cholesterol distribution within the context of infectious diseases.
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Affiliation(s)
- Kerstin K Schwickert
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University, Jena, Germany; Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany; Department of Chemistry, Johannes Gutenberg-University, 55122, Mainz, Germany
| | - Mirco Glitscher
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Daniela Bender
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Nuka Ivalu Benz
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Robin Murra
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Kevin Schwickert
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, 55122, Mainz, Germany
| | - Steffen Pfalzgraf
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany
| | - Tanja Schirmeister
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, 55122, Mainz, Germany
| | - Ute A Hellmich
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University, Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Frankfurt, Germany; Cluster of Excellence "Balance of the Microverse", Friedrich Schiller University, Jena, Germany.
| | - Eberhard Hildt
- Department of Virology, Paul-Ehrlich-Institut, 63225, Langen, Germany.
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Bao X, Zhuang T, Xu Y, Chen L, Feng L, Yao H. Exosomes secreted by CSFV-infected cells evade neutralizing antibody to activate innate immune responses and establish productive infection in recipient cells. Vet Microbiol 2024; 292:110062. [PMID: 38518631 DOI: 10.1016/j.vetmic.2024.110062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 03/10/2024] [Accepted: 03/15/2024] [Indexed: 03/24/2024]
Abstract
Exosomes, which are small membrane-enclosed vesicles, are actively released into the extracellular space by a variety of cells. Growing evidence indicates that exosomes derived from virus-infected cells can selectively encapsulate viral proteins, genetic materials, or even entire virions. This enables them to mediate cell-to-cell communication and facilitate virus transmission. Classical swine fever (CSF) is a disease listed by the World Organisation for Animal Health (WOAH) Terrestrial Animal Health Code and must be reported to the organisation. It is caused by classical swine fever virus (CSFV) belonging to the Flaviviridae family. Recent studies have demonstrated that extracellular vesicles originating from autophagy can facilitate the antibody-resistant spread of classical swine fever virus. However, due to the extreme difficulty in achieving a complete separation from virions, the role of exosomes during CSFV infection and proliferation remains elusive. In this study, we ingeniously chose to perform immunoprecipitation (IP) targeting the CSFV E2 protein, thereby achieving the complete removal of infectious virions. Subsequently, we discovered that the purified exosomes are shown to contain viral genomic RNA and partial viral proteins. Furthermore, exosomes secreted by CSFV-infected cells can evade CSFV-specific neutralizing antibodies, establish subsequent infection, and stimulate innate immune system after uptake by recipient cells. In summary, exosomes play a critical role in CSFV transmission. This is of great significance for in-depth exploration of the characteristics of CSFV and its complex interactions with the host.
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Affiliation(s)
- Xi Bao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China; Institute of Veterinary Immunology & Engineering, National Research Center of Engineering and Technology for Veterinary Biologicals, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China
| | - Tenghan Zhuang
- Institute of Veterinary Immunology & Engineering, National Research Center of Engineering and Technology for Veterinary Biologicals, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China
| | - Yue Xu
- Institute of Veterinary Immunology & Engineering, National Research Center of Engineering and Technology for Veterinary Biologicals, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China
| | - Li Chen
- Institute of Veterinary Immunology & Engineering, National Research Center of Engineering and Technology for Veterinary Biologicals, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China
| | - Lei Feng
- Institute of Veterinary Immunology & Engineering, National Research Center of Engineering and Technology for Veterinary Biologicals, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China; GuoTai (Taizhou) Center of Technology Innovation for Veterinary Biologicals, Taizhou 225300, China; Laboratory for Food Quality and Safety State Key Laboratory Cultivation Base, Ministry of Science and Technology, Nanjing, Jiangsu, China; School of Pharmacy, Jiangsu University, Zhenjiang, Jiangsu, China.
| | - Huochun Yao
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
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Nisar KS, Anjum MW, Raja MAZ, Shoaib M. Recurrent neural network for the dynamics of Zika virus spreading. AIMS Public Health 2024; 11:432-458. [PMID: 39027393 PMCID: PMC11252581 DOI: 10.3934/publichealth.2024022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 03/06/2024] [Accepted: 03/13/2024] [Indexed: 07/20/2024] Open
Abstract
Recurrent Neural Networks (RNNs), a type of machine learning technique, have recently drawn a lot of interest in numerous fields, including epidemiology. Implementing public health interventions in the field of epidemiology depends on efficient modeling and outbreak prediction. Because RNNs can capture sequential dependencies in data, they have become highly effective tools in this field. In this paper, the use of RNNs in epidemic modeling is examined, with a focus on the extent to which they can handle the inherent temporal dynamics in the spread of diseases. The mathematical representation of epidemics requires taking time-dependent variables into account, such as the rate at which infections spread and the long-term effects of interventions. The goal of this study is to use an intelligent computing solution based on RNNs to provide numerical performances and interpretations for the SEIR nonlinear system based on the propagation of the Zika virus (SEIRS-PZV) model. The four patient dynamics, namely susceptible patients S(y), exposed patients admitted in a hospital E(y), the fraction of infective individuals I(y), and recovered patients R(y), are represented by the epidemic version of the nonlinear system, or the SEIR model. SEIRS-PZV is represented by ordinary differential equations (ODEs), which are then solved by the Adams method using the Mathematica software to generate a dataset. The dataset was used as an output for the RNN to train the model and examine results such as regressions, correlations, error histograms, etc. For RNN, we used 100% to train the model with 15 hidden layers and a delay of 2 seconds. The input for the RNN is a time series sequence from 0 to 5, with a step size of 0.05. In the end, we compared the approximated solution with the exact solution by plotting them on the same graph and generating the absolute error plot for each of the 4 cases of SEIRS-PZV. Predictions made by the model appeared to be become more accurate when the mean squared error (MSE) decreased. An increased fit to the observed data was suggested by this decrease in the MSE, which suggested that the variance between the model's predicted values and the actual values was dropping. A minimal absolute error almost equal to zero was obtained, which further supports the usefulness of the suggested strategy. A small absolute error shows the degree to which the model's predictions matches the ground truth values, thus indicating the level of accuracy and precision for the model's output.
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Affiliation(s)
- Kottakkaran Sooppy Nisar
- Department of Mathematics, College of Science and Humanities in Al Kharj, Prince Sattam bin Abdulaziz University, 11942, Saudi Arabia
- Saveetha School of Engineering, SIMATS, Chennai, India
| | | | - Muhammad Asif Zahoor Raja
- Future Technology Research Center, National Yunlin University of Science and Technology, 123 University Road, Section .3, Douliou, Yunlin 64002, Taiwan, R.O.C
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Jain A, Govindan R, Berkman AR, Luban J, Díaz-Salinas MA, Durham ND, Munro JB. Regulation of Ebola GP conformation and membrane binding by the chemical environment of the late endosome. PLoS Pathog 2023; 19:e1011848. [PMID: 38055723 PMCID: PMC10727438 DOI: 10.1371/journal.ppat.1011848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/18/2023] [Accepted: 11/20/2023] [Indexed: 12/08/2023] Open
Abstract
Interaction between the Ebola virus envelope glycoprotein (GP) and the endosomal membrane is an essential step during virus entry into the cell. Acidic pH and Ca2+ have been implicated in mediating the GP-membrane interaction. However, the molecular mechanism by which these environmental factors regulate the conformational changes that enable engagement of GP with the target membrane is unknown. Here, we apply fluorescence correlation spectroscopy (FCS) and single-molecule Förster resonance energy transfer (smFRET) imaging to elucidate how the acidic pH, Ca2+ and anionic phospholipids in the late endosome promote GP-membrane interaction, thereby facilitating virus entry. We find that bis(monoacylglycero)phosphate (BMP), which is specific to the late endosome, is especially critical in determining the Ca2+-dependence of the GP-membrane interaction. Molecular dynamics (MD) simulations suggested residues in GP that sense pH and induce conformational changes that make the fusion loop available for insertion into the membrane. We similarly confirm residues in the fusion loop that mediate GP's interaction with Ca2+, which likely promotes local conformational changes in the fusion loop and mediates electrostatic interactions with the anionic phospholipids. Collectively, our results provide a mechanistic understanding of how the environment of the late endosome regulates the timing and efficiency of virus entry.
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Affiliation(s)
- Aastha Jain
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, Worcester, Massachusetts, United States of America
| | - Ramesh Govindan
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, Worcester, Massachusetts, United States of America
- Medical Scientist Training Program, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Alex R. Berkman
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, Worcester, Massachusetts, United States of America
| | - Jeremy Luban
- Program in Molecular Medicine, UMass Chan Medical School, Worcester, Massachusetts, United States of America
- Department of Biochemistry and Molecular Biotechnology, UMass Chan Medical School, Worcester, Massachusetts, United States of America
| | - Marco A. Díaz-Salinas
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, Worcester, Massachusetts, United States of America
| | - Natasha D. Durham
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, Worcester, Massachusetts, United States of America
| | - James B. Munro
- Department of Microbiology and Physiological Systems, UMass Chan Medical School, Worcester, Massachusetts, United States of America
- Department of Biochemistry and Molecular Biotechnology, UMass Chan Medical School, Worcester, Massachusetts, United States of America
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6
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Jain A, Govindan R, Berkman A, Luban J, Durham ND, Munro J. Regulation of Ebola GP conformation and membrane binding by the chemical environment of the late endosome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.18.524651. [PMID: 36711925 PMCID: PMC9882366 DOI: 10.1101/2023.01.18.524651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Interaction between the Ebola virus envelope glycoprotein (GP) and the endosomal membrane is an essential step during virus entry into the cell. Acidic pH and Ca2+ have been implicated in mediating the GP-membrane interaction. However, the molecular mechanism by which these environmental factors regulate the conformational changes that enable engagement of GP with the target membrane is unknown. Here, we apply fluorescence correlation spectroscopy (FCS) and single-molecule Forster resonance energy transfer (smFRET) imaging to elucidate how the acidic pH, Ca2+ and anionic phospholipids in the late endosome promote GP-membrane interaction, thereby facilitating virus entry. We find that bis(monoacylglycero)phosphate (BMP), which is specific to the late endosome, is especially critical in determining the Ca2+-dependence of the GP-membrane interaction. Molecular dynamics (MD) simulations suggested residues in GP that sense pH and induce conformational changes that make the fusion loop available for insertion into the membrane. We similarly confirm residues in the fusion loop that mediate GPs interaction with Ca2+, which likely promotes local conformational changes in the fusion loop and mediates electrostatic interactions with the anionic phospholipids. Collectively, our results provide a mechanistic understanding of how the environment of the late endosome regulates the timing and efficiency of virus entry.
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7
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Bou JV, Taguwa S, Matsuura Y. Trick-or-Trap: Extracellular Vesicles and Viral Transmission. Vaccines (Basel) 2023; 11:1532. [PMID: 37896936 PMCID: PMC10611016 DOI: 10.3390/vaccines11101532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/15/2023] [Accepted: 09/23/2023] [Indexed: 10/29/2023] Open
Abstract
Extracellular vesicles (EVs) are lipid membrane-enclosed particles produced by most cells, playing important roles in various biological processes. They have been shown to be involved in antiviral mechanisms such as transporting antiviral molecules, transmitting viral resistance, and participating in antigen presentation. While viral transmission was traditionally thought to occur through independent viral particles, the process of viral infection is complex, with multiple barriers and challenges that viruses must overcome for successful infection. As a result, viruses exploit the intercellular communication pathways of EVs to facilitate cluster transmission, increasing their chances of infecting target cells. Viral vesicle transmission offers two significant advantages. Firstly, it enables the collective transmission of viral genomes, increasing the chances of infection and promoting interactions between viruses in subsequent generations. Secondly, the use of vesicles as vehicles for viral transmission provides protection to viral particles against environmental factors, while also expanding the cell tropism allowing viruses to reach cells in a receptor-independent manner. Understanding the role of EVs in viral transmission is crucial for comprehending virus evolution and developing innovative antiviral strategies, therapeutic interventions, and vaccine approaches.
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Affiliation(s)
- Juan-Vicente Bou
- Laboratory of Virus Control, Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Shuhei Taguwa
- Laboratory of Virus Control, Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan
- Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Center for Advanced Modalities and DDS, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yoshiharu Matsuura
- Laboratory of Virus Control, Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan
- Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Center for Advanced Modalities and DDS, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan
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Bollman B, Nunna N, Bahl K, Hsiao CJ, Bennett H, Butler S, Foreman B, Burgomaster KE, Aleshnick M, Kong WP, Fisher BE, Ruckwardt TJ, Morabito KM, Graham BS, Dowd KA, Pierson TC, Carfi A. An optimized messenger RNA vaccine candidate protects non-human primates from Zika virus infection. NPJ Vaccines 2023; 8:58. [PMID: 37080988 PMCID: PMC10119314 DOI: 10.1038/s41541-023-00656-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 03/29/2023] [Indexed: 04/22/2023] Open
Abstract
Zika virus (ZIKV), an arbovirus transmitted by mosquitoes, was identified as a cause of congenital disease during a major outbreak in the Americas in 2016. Vaccine design strategies relied on limited available isolate sequence information due to the rapid response necessary. The first-generation ZIKV mRNA vaccine, mRNA-1325, was initially generated and, as additional strain sequences became available, a second mRNA vaccine, mRNA-1893, was developed. Herein, we compared the immune responses following mRNA-1325 and mRNA-1893 vaccination and reported that mRNA-1893 generated comparable neutralizing antibody titers to mRNA-1325 at 1/20th of the dose and provided complete protection from ZIKV challenge in non-human primates. In-depth characterization of these vaccines indicated that the observed immunologic differences could be attributed to a single amino acid residue difference that compromised mRNA-1325 virus-like particle formation.
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Affiliation(s)
| | | | | | | | | | | | - Bryant Foreman
- Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Katherine E Burgomaster
- Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Maya Aleshnick
- Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Wing-Pui Kong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Brian E Fisher
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Tracy J Ruckwardt
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kaitlyn M Morabito
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kimberly A Dowd
- Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Theodore C Pierson
- Viral Pathogenesis Section, Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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Merchant M, Mata CP, Liu Y, Zhai H, Protasio AV, Modis Y. A bioactive phlebovirus-like envelope protein in a hookworm endogenous virus. SCIENCE ADVANCES 2022; 8:eabj6894. [PMID: 35544562 PMCID: PMC9094657 DOI: 10.1126/sciadv.abj6894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 03/25/2022] [Indexed: 05/02/2023]
Abstract
Endogenous viral elements (EVEs), accounting for 15% of our genome, serve as a genetic reservoir from which new genes can emerge. Nematode EVEs are particularly diverse and informative of virus evolution. We identify Atlas virus-an intact retrovirus-like EVE in the human hookworm Ancylostoma ceylanicum, with an envelope protein genetically related to GN-GC glycoproteins from the family Phenuiviridae. A cryo-EM structure of Atlas GC reveals a class II viral membrane fusion protein fold not previously seen in retroviruses. Atlas GC has the structural hallmarks of an active fusogen. Atlas GC trimers insert into membranes with endosomal lipid compositions and low pH. When expressed on the plasma membrane, Atlas GC has cell-cell fusion activity. With its preserved biological activities, Atlas GC has the potential to acquire a cellular function. Our work reveals structural plasticity in reverse-transcribing RNA viruses.
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Affiliation(s)
- Monique Merchant
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge CB2 0AW, UK
| | - Carlos P. Mata
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge CB2 0AW, UK
| | - Yangci Liu
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge CB2 0AW, UK
| | - Haoming Zhai
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge CB2 0AW, UK
| | - Anna V. Protasio
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
- Christ’s College, University of Cambridge, St Andrew’s Street, Cambridge, CB2 3BU, UK
| | - Yorgo Modis
- Molecular Immunity Unit, Department of Medicine, University of Cambridge, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge CB2 0AW, UK
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Development of antiviral carbon quantum dots that target the Japanese encephalitis virus envelope protein. J Biol Chem 2022; 298:101957. [PMID: 35452675 PMCID: PMC9123278 DOI: 10.1016/j.jbc.2022.101957] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 04/06/2022] [Accepted: 04/07/2022] [Indexed: 12/23/2022] Open
Abstract
Japanese encephalitis is a mosquito-borne disease caused by the Japanese encephalitis virus (JEV) that is prevalent in Asia and the Western Pacific. Currently, there is no effective treatment for Japanese encephalitis. Curcumin (Cur) is a compound extracted from the roots of Curcuma longa, and many studies have reported its antiviral and anti-inflammatory activities. However, the high cytotoxicity and very low solubility of Cur limit its biomedical applications. In this study, Cur carbon quantum dots (Cur-CQDs) were synthesized by mild pyrolysis-induced polymerization and carbonization, leading to higher water solubility and lower cytotoxicity, as well as superior antiviral activity against JEV infection. We found that Cur-CQDs effectively bound to the E protein of JEV, preventing viral entry into the host cells. In addition, after continued treatment of JEV with Cur-CQDs, a mutant strain of JEV was evolved that did not support binding of Cur-CQDs to the JEV envelope. Using transmission electron microscopy, biolayer interferometry, and molecular docking analysis, we revealed that the S123R and K312R mutations in the E protein play a key role in binding Cur-CQDs. The S123 and K312 residues are located in structural domains II and III of the E protein, respectively, and are responsible for binding to receptors on and fusing with the cell membrane. Taken together, our results suggest that the E protein of flaviviruses represents a potential target for the development of CQD-based inhibitors to prevent or treat viral infections.
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Zhang L, Zhou D, Li Q, Zhu S, Imran M, Duan H, Cao S, Ke S, Ye J. The Antiviral Effect of Novel Steroidal Derivatives on Flaviviruses. Front Microbiol 2021; 12:727236. [PMID: 34690968 PMCID: PMC8527100 DOI: 10.3389/fmicb.2021.727236] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 09/09/2021] [Indexed: 11/13/2022] Open
Abstract
Flaviviruses are the major emerging arthropod-borne pathogens globally. However, there is still no practical anti-flavivirus approach. Therefore, existing and emerging flaviviruses desperately need active broad-spectrum drugs. In the present study, the antiviral effect of steroidal dehydroepiandrosterone (DHEA) and 23 synthetic derivatives against flaviviruses such as Japanese encephalitis virus (JEV), Zika virus (ZIKV), and Dengue virus (DENV) were appraised by examining the characteristics of virus infection both in vitro and in vivo. Our results revealed that AV1003, AV1004 and AV1017 were the most potent inhibitors of flavivirus propagation in cells. They mainly suppress the viral infection in the post-invasion stage in a dose-dependent manner. Furthermore, orally administered compound AV1004 protected mice from lethal JEV infection by increasing the survival rate and reducing the viral load in the brain of infected mice. These results indicate that the compound AV1004 might be a potential therapeutic drug against JEV infection. These DHEA derivatives may provide lead scaffolds for further design and synthesis of potential anti-flavivirus potential drugs.
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Affiliation(s)
- Luping Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
| | - Dengyuan Zhou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
| | - Qiuyan Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
| | - Shuo Zhu
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
| | - Muhammad Imran
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
| | - Hongyu Duan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
| | - Shengbo Cao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
| | - Shaoyong Ke
- National Biopesticide Engineering Research Center, Hubei Biopesticide Engineering Research Center, Hubei Academy of Agricultural Sciences, Wuhan, China
| | - Jing Ye
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, China
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12
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Farfan-Morales CN, Cordero-Rivera CD, Reyes-Ruiz JM, Hurtado-Monzón AM, Osuna-Ramos JF, González-González AM, De Jesús-González LA, Palacios-Rápalo SN, Del Ángel RM. Anti-flavivirus Properties of Lipid-Lowering Drugs. Front Physiol 2021; 12:749770. [PMID: 34690817 PMCID: PMC8529048 DOI: 10.3389/fphys.2021.749770] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/20/2021] [Indexed: 12/11/2022] Open
Abstract
Although Flaviviruses such as dengue (DENV) and zika (ZIKV) virus are important human pathogens, an effective vaccine or antiviral treatment against them is not available. Hence, the search for new strategies to control flavivirus infections is essential. Several studies have shown that the host lipid metabolism could be an antiviral target because cholesterol and other lipids are required during the replicative cycle of different Flaviviridae family members. FDA-approved drugs with hypolipidemic effects could be an alternative for treating flavivirus infections. However, a better understanding of the regulation between host lipid metabolism and signaling pathways triggered during these infections is required. The metabolic pathways related to lipid metabolism modified during DENV and ZIKV infection are analyzed in this review. Additionally, the role of lipid-lowering drugs as safe host-targeted antivirals is discussed.
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Affiliation(s)
- Carlos Noe Farfan-Morales
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Mexico City, Mexico
| | - Carlos Daniel Cordero-Rivera
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Mexico City, Mexico
| | - José Manuel Reyes-Ruiz
- Unidad Médica de Alta Especialidad, Hospital de Especialidades No. 14, Centro Médico Nacional "Adolfo Ruiz Cortines," Instituto Mexicano del Seguro Social, Heroica Veracruz, Mexico
| | - Arianna M Hurtado-Monzón
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Mexico City, Mexico
| | - Juan Fidel Osuna-Ramos
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Mexico City, Mexico
| | - Arely M González-González
- Laboratorio de Ingeniería Tisular y Medicina Traslacional, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México (UNAM), Mexico City, Mexico
| | - Luis Adrián De Jesús-González
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Mexico City, Mexico
| | - Selvin Noé Palacios-Rápalo
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Mexico City, Mexico
| | - Rosa María Del Ángel
- Department of Infectomics and Molecular Pathogenesis, Center for Research and Advanced Studies (CINVESTAV-IPN), Mexico City, Mexico
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13
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The late endosome-resident lipid bis(monoacylglycero)phosphate is a cofactor for Lassa virus fusion. PLoS Pathog 2021; 17:e1009488. [PMID: 34492091 PMCID: PMC8448326 DOI: 10.1371/journal.ppat.1009488] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 09/17/2021] [Accepted: 08/25/2021] [Indexed: 11/20/2022] Open
Abstract
Arenavirus entry into host cells occurs through a low pH-dependent fusion with late endosomes that is mediated by the viral glycoprotein complex (GPC). The mechanisms of GPC-mediated membrane fusion and of virus targeting to late endosomes are not well understood. To gain insights into arenavirus fusion, we examined cell-cell fusion induced by the Old World Lassa virus (LASV) GPC complex. LASV GPC-mediated cell fusion is more efficient and occurs at higher pH with target cells expressing human LAMP1 compared to cells lacking this cognate receptor. However, human LAMP1 is not absolutely required for cell-cell fusion or LASV entry. We found that GPC-induced fusion progresses through the same lipid intermediates as fusion mediated by other viral glycoproteins–a lipid curvature-sensitive intermediate upstream of hemifusion and a hemifusion intermediate downstream of acid-dependent steps that can be arrested in the cold. Importantly, GPC-mediated fusion and LASV pseudovirus entry are specifically augmented by an anionic lipid, bis(monoacylglycero)phosphate (BMP), which is highly enriched in late endosomes. This lipid also specifically promotes cell fusion mediated by Junin virus GPC, an unrelated New World arenavirus. We show that BMP promotes late steps of LASV fusion downstream of hemifusion–the formation and enlargement of fusion pores. The BMP-dependence of post-hemifusion stages of arenavirus fusion suggests that these viruses evolved to use this lipid as a cofactor to selectively fuse with late endosomes. Pathogenic arenaviruses pose a serious health threat. The viral envelope glycoprotein GPC mediates attachment to host cells and drives virus entry via endocytosis and low pH-dependent fusion within late endosomes. Understanding the host factors and processes that are essential for arenavirus fusion may identify novel therapeutic targets. To delineate the mechanism of arenavirus entry, we examined cell-cell fusion induced by the Old World Lassa virus GPC proteins at low pH. Lassa GPC-mediated fusion was augmented by the human LAMP1 receptor and progressed through lipid curvature-sensitive intermediates, such as hemifusion (merger of contacting leaflets of viral and cell membrane without the formation of a fusion pore). We found that most GPC-mediated fusion events were off-path hemifusion structures and that the transition from hemifusion to full fusion and fusion pore enlargement were specifically promoted by an anionic lipid, bis(monoacylglycero)phosphate, which is highly enriched in late endosomes. This lipid also specifically promotes fusion of unrelated New World Junin arenavirus. Our results imply that arenaviruses evolved to use bis(monoacylglycero)phosphate to enter cells from late endosomes.
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14
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Ceramide and Related Molecules in Viral Infections. Int J Mol Sci 2021; 22:ijms22115676. [PMID: 34073578 PMCID: PMC8197834 DOI: 10.3390/ijms22115676] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 05/21/2021] [Accepted: 05/21/2021] [Indexed: 02/08/2023] Open
Abstract
Ceramide is a lipid messenger at the heart of sphingolipid metabolism. In concert with its metabolizing enzymes, particularly sphingomyelinases, it has key roles in regulating the physical properties of biological membranes, including the formation of membrane microdomains. Thus, ceramide and its related molecules have been attributed significant roles in nearly all steps of the viral life cycle: they may serve directly as receptors or co-receptors for viral entry, form microdomains that cluster entry receptors and/or enable them to adopt the required conformation or regulate their cell surface expression. Sphingolipids can regulate all forms of viral uptake, often through sphingomyelinase activation, and mediate endosomal escape and intracellular trafficking. Ceramide can be key for the formation of viral replication sites. Sphingomyelinases often mediate the release of new virions from infected cells. Moreover, sphingolipids can contribute to viral-induced apoptosis and morbidity in viral diseases, as well as virus immune evasion. Alpha-galactosylceramide, in particular, also plays a significant role in immune modulation in response to viral infections. This review will discuss the roles of ceramide and its related molecules in the different steps of the viral life cycle. We will also discuss how novel strategies could exploit these for therapeutic benefit.
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15
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Gruenberg J. Life in the lumen: The multivesicular endosome. Traffic 2021; 21:76-93. [PMID: 31854087 PMCID: PMC7004041 DOI: 10.1111/tra.12715] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/30/2019] [Accepted: 10/31/2019] [Indexed: 12/12/2022]
Abstract
The late endosomes/endo‐lysosomes of vertebrates contain an atypical phospholipid, lysobisphosphatidic acid (LBPA) (also termed bis[monoacylglycero]phosphate [BMP]), which is not detected elsewhere in the cell. LBPA is abundant in the membrane system present in the lumen of this compartment, including intralumenal vesicles (ILVs). In this review, the current knowledge on LBPA and LBPA‐containing membranes will be summarized, and their role in the control of endosomal cholesterol will be outlined. Some speculations will also be made on how this system may be overwhelmed in the cholesterol storage disorder Niemann‐Pick C. Then, the roles of intralumenal membranes in endo‐lysosomal dynamics and functions will be discussed in broader terms. Likewise, the mechanisms that drive the biogenesis of intralumenal membranes, including ESCRTs, will also be discussed, as well as their diverse composition and fate, including degradation in lysosomes and secretion as exosomes. This review will also discuss how intralumenal membranes are hijacked by pathogenic agents during intoxication and infection, and what is the biochemical composition and function of the intra‐endosomal lumenal milieu. Finally, this review will allude to the size limitations imposed on intralumenal vesicle functions and speculate on the possible role of LBPA as calcium chelator in the acidic calcium stores of endo‐lysosomes.
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Affiliation(s)
- Jean Gruenberg
- Biochemistry Department, University of Geneva, Geneva, Switzerland
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16
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Xie S, Zhang H, Liang Z, Yang X, Cao R. AXL, an Important Host Factor for DENV and ZIKV Replication. Front Cell Infect Microbiol 2021; 11:575346. [PMID: 33954117 PMCID: PMC8092360 DOI: 10.3389/fcimb.2021.575346] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 02/18/2021] [Indexed: 12/13/2022] Open
Abstract
Flaviviruses, as critically important pathogens, are still major public health problems all over the world. For instance, the evolution of ZIKV led to large-scale outbreaks in the Yap island in 2007. DENV was considered by the World Health Organization (WHO) as one of the 10 threats to global health in 2019. Enveloped viruses hijack a variety of host factors to complete its replication cycle. Phosphatidylserine (PS) receptor, AXL, is considered to be a candidate receptor for flavivirus invasion. In this review, we discuss the molecular structure of ZIKV and DENV, and how they interact with AXL to successfully invade host cells. A more comprehensive understanding of the molecular mechanisms of flavivirus-AXL interaction will provide crucial insights into the virus infection process and the development of anti-flavivirus therapeutics.
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Affiliation(s)
- Shengda Xie
- Ministry of Education (MOE) Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Huiru Zhang
- Ministry of Education (MOE) Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Zhenjie Liang
- Ministry of Education (MOE) Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Xingmiao Yang
- Ministry of Education (MOE) Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Ruibing Cao
- Ministry of Education (MOE) Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
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17
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Wilken L, Rimmelzwaan GF. Adaptive Immunity to Dengue Virus: Slippery Slope or Solid Ground for Rational Vaccine Design? Pathogens 2020; 9:pathogens9060470. [PMID: 32549226 PMCID: PMC7350362 DOI: 10.3390/pathogens9060470] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/11/2020] [Accepted: 06/12/2020] [Indexed: 12/15/2022] Open
Abstract
The four serotypes of dengue virus are the most widespread causes of arboviral disease, currently placing half of the human population at risk of infection. Pre-existing immunity to one dengue virus serotype can predispose to severe disease following secondary infection with a different serotype. The phenomenon of immune enhancement has complicated vaccine development and likely explains the poor long-term safety profile of a recently licenced dengue vaccine. Therefore, alternative vaccine strategies should be considered. This review summarises studies dissecting the adaptive immune responses to dengue virus infection and (experimental) vaccination. In particular, we discuss the roles of (i) neutralising antibodies, (ii) antibodies to non-structural protein 1, and (iii) T cells in protection and pathogenesis. We also address how these findings could translate into next-generation vaccine approaches that mitigate the risk of enhanced dengue disease. Finally, we argue that the development of a safe and efficacious dengue vaccine is an attainable goal.
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18
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Abstract
Viruses manipulate cellular lipids and membranes at each stage of their life cycle. This includes lipid-receptor interactions, the fusion of viral envelopes with cellular membranes during endocytosis, the reorganization of cellular membranes to form replication compartments, and the envelopment and egress of virions. In addition to the physical interactions with cellular membranes, viruses have evolved to manipulate lipid signaling and metabolism to benefit their replication. This review summarizes the strategies that viruses use to manipulate lipids and membranes at each stage in the viral life cycle.
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Affiliation(s)
- Ellen Ketter
- Department of Microbiology, The University of Chicago, Chicago, Illinois 60637, USA;
| | - Glenn Randall
- Department of Microbiology, The University of Chicago, Chicago, Illinois 60637, USA;
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19
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Lang J, Bohn P, Bhat H, Jastrow H, Walkenfort B, Cansiz F, Fink J, Bauer M, Olszewski D, Ramos-Nascimento A, Duhan V, Friedrich SK, Becker KA, Krawczyk A, Edwards MJ, Burchert A, Huber M, Friebus-Kardash J, Göthert JR, Hardt C, Probst HC, Schumacher F, Köhrer K, Kleuser B, Babiychuk EB, Sodeik B, Seibel J, Greber UF, Lang PA, Gulbins E, Lang KS. Acid ceramidase of macrophages traps herpes simplex virus in multivesicular bodies and protects from severe disease. Nat Commun 2020; 11:1338. [PMID: 32165633 PMCID: PMC7067866 DOI: 10.1038/s41467-020-15072-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 02/17/2020] [Indexed: 12/20/2022] Open
Abstract
Macrophages have important protective functions during infection with herpes simplex virus type 1 (HSV-1). However, molecular mechanisms that restrict viral propagation and protect from severe disease are unclear. Here we show that macrophages take up HSV-1 via endocytosis and transport the virions into multivesicular bodies (MVBs). In MVBs, acid ceramidase (aCDase) converts ceramide into sphingosine and increases the formation of sphingosine-rich intraluminal vesicles (ILVs). Once HSV-1 particles reach MVBs, sphingosine-rich ILVs bind to HSV-1 particles, which restricts fusion with the limiting endosomal membrane and prevents cellular infection. Lack of aCDase in macrophage cultures or in Asah1-/- mice results in replication of HSV-1 and Asah1-/- mice die soon after systemic or intravaginal inoculation. The treatment of macrophages with sphingosine enhancing compounds blocks HSV-1 propagation, suggesting a therapeutic potential of this pathway. In conclusion, aCDase loads ILVs with sphingosine, which prevents HSV-1 capsids from penetrating into the cytosol.
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Affiliation(s)
- Judith Lang
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Patrick Bohn
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Hilal Bhat
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Holger Jastrow
- Institute of Anatomy, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany.,Institut for Experimental Immunology and Imaging, Imaging Center Essen, Electron Microscopy Unit, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Bernd Walkenfort
- Institut for Experimental Immunology and Imaging, Imaging Center Essen, Electron Microscopy Unit, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Feyza Cansiz
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Julian Fink
- Institute of Organic Chemistry, Julius-Maximilians University of Würzburg, Am Hubland, Würzburg, D-97074, Germany
| | - Michael Bauer
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstr. 190, CH-8057, Zurich, Switzerland
| | - Dominik Olszewski
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstr. 190, CH-8057, Zurich, Switzerland
| | - Ana Ramos-Nascimento
- Institute of Virology, Hannover Medical School, Carl-Neuberg-Str. 1, Hannover, D-30625, Germany
| | - Vikas Duhan
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Sarah-Kim Friedrich
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Katrin Anne Becker
- Institute of Molecular Biology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Adalbert Krawczyk
- Institute for Virology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany.,Department of Infectious Diseases, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Michael J Edwards
- Department of Surgery, University of Cincinnati, Cincinnati, OH, USA
| | - Andreas Burchert
- Department of Hematology, Oncology and Immunology, University Hospital Giessen and Marburg, Campus Marburg, Baldingerstr., Marburg, D-35043, Germany
| | - Magdalena Huber
- Institute of Medical Microbiology and Hospital Hygiene, Philipps-University Marburg, Hans-Meerwein Str. 2, Marburg, D-35043, Germany
| | - Justa Friebus-Kardash
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Joachim R Göthert
- Department of Hematology, West German Cancer Center, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Cornelia Hardt
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany
| | - Hans Christian Probst
- Institute of Immunology, University Medical Center Mainz, Langenbeckstr. 1, Mainz, D-55131, Germany
| | - Fabian Schumacher
- Institute of Molecular Biology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany.,Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert Allee 114-116, Nuthetal, D-14558, Germany
| | - Karl Köhrer
- Biological and Medical Research Center (BMFZ), Heinrich-Heine-University, Universitätsstr. 1, Düsseldorf, D-40225, Germany
| | - Burkhard Kleuser
- Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert Allee 114-116, Nuthetal, D-14558, Germany
| | - Eduard B Babiychuk
- Institute of Anatomy, University of Bern, Baltzerstr. 4, CH-3012, Bern, Switzerland
| | - Beate Sodeik
- Institute of Virology, Hannover Medical School, Carl-Neuberg-Str. 1, Hannover, D-30625, Germany.,Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Carl-Neuberg-Str. 1, Hannover, D-30625, Germany
| | - Jürgen Seibel
- Institute of Organic Chemistry, Julius-Maximilians University of Würzburg, Am Hubland, Würzburg, D-97074, Germany
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstr. 190, CH-8057, Zurich, Switzerland
| | - Philipp A Lang
- Department of Molecular Medicine II, Medical Faculty, Heinrich Heine University, Universitätsstr. 1, Düsseldorf, D-40225, Germany
| | - Erich Gulbins
- Institute of Molecular Biology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany.,Department of Surgery, University of Cincinnati, Cincinnati, OH, USA
| | - Karl S Lang
- Institute of Immunology, University of Duisburg-Essen, Hufelandstr. 55, Essen, D-45147, Germany.
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20
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Saxena SK, Kumar S, Haikerwal A. Animal Flaviviruses. EMERGING AND TRANSBOUNDARY ANIMAL VIRUSES 2020. [DOI: 10.1007/978-981-15-0402-0_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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21
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Urbanelli L, Buratta S, Tancini B, Sagini K, Delo F, Porcellati S, Emiliani C. The Role of Extracellular Vesicles in Viral Infection and Transmission. Vaccines (Basel) 2019; 7:vaccines7030102. [PMID: 31466253 PMCID: PMC6789493 DOI: 10.3390/vaccines7030102] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/12/2019] [Accepted: 08/22/2019] [Indexed: 12/12/2022] Open
Abstract
Extracellular vesicles (EVs) have been found to be released by any type of cell and can be retrieved in every circulating body fluid, namely blood (plasma, serum), saliva, milk, and urine. EVs were initially considered a cellular garbage disposal tool, but later it became evident that they are involved in intercellular signaling. There is evidence that viruses can use EV endocytic routes to enter uninfected cells and hijack the EV secretory pathway to exit infected cells, thus illustrating that EVs and viruses share common cell entry and biogenesis mechanisms. Moreover, EVs play a role in immune response against viral pathogens. EVs incorporate and spread both viral and host factors, thereby prompting or inhibiting immune responses towards them via a multiplicity of mechanisms. The involvement of EVs in immune responses, and their potential use as agents modulating viral infection, will be examined. Although further studies are needed, the engineering of EVs could package viral elements or host factors selected for their immunostimulatory properties, to be used as vaccines or tolerogenic tools in autoimmune diseases.
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Affiliation(s)
- Lorena Urbanelli
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Via del Giochetto, 06123 Perugia, Italy.
| | - Sandra Buratta
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Via del Giochetto, 06123 Perugia, Italy
| | - Brunella Tancini
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Via del Giochetto, 06123 Perugia, Italy
| | - Krizia Sagini
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Via del Giochetto, 06123 Perugia, Italy
| | - Federica Delo
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Via del Giochetto, 06123 Perugia, Italy
| | - Serena Porcellati
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Via del Giochetto, 06123 Perugia, Italy
| | - Carla Emiliani
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Via del Giochetto, 06123 Perugia, Italy
- Centro di Eccellenza sui Materiali Innovativi Nanostrutturati (CEMIN), University of Perugia, Via del Giochetto, 06123 Perugia, Italy
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22
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Joyce S, Nour AM. Blocking transmembrane219 protein signaling inhibits autophagy and restores normal cell death. PLoS One 2019; 14:e0218091. [PMID: 31220095 PMCID: PMC6586287 DOI: 10.1371/journal.pone.0218091] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 05/24/2019] [Indexed: 02/04/2023] Open
Abstract
Autophagy plays a vital role in tumor therapy and survival of dormant tumor cells. Here we describe a novel function of a protein known as Transmembrane 219 (TM219) as an autophagy activator. TM219 is a small membrane protein expressed in all known human tissues except the thymus. We used biochemical approaches to identify calmodulin and calmodulin dependent protein kinase II as a part of TM219 protein complex. Then, we employed in vitro reconstitution system and fluorescence anisotropy to study the requirements of TM219 to bind calmodulin in vitro. We also used this system to study the effects of a synthetic peptide derived from the sequence of the short cytoplasmic tail of TM219 (SCTT) on calmodulin-TM219 receptor interactions. We conjugated SCTT peptide with a pH Low Insertion peptide (pHLIP) for optimal cellular delivery. We finally tested the effects of SCTT-pHLIP on triple negative human breast cancer cells in three dimension culture. Our data defined a novel function of TM219 protein and an efficient approach to inhibit it.
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Affiliation(s)
- Sean Joyce
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
| | - Adel M. Nour
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, United States of America
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23
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Campos RK, Garcia-Blanco MA, Bradrick SS. Roles of Pro-viral Host Factors in Mosquito-Borne Flavivirus Infections. Curr Top Microbiol Immunol 2019; 419:43-67. [PMID: 28688087 DOI: 10.1007/82_2017_26] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Identification and analysis of viral host factors is a growing area of research which aims to understand the how viruses molecularly interface with the host cell. Investigations into flavivirus-host interactions has led to new discoveries in viral and cell biology, and will potentially bolster strategies to control the important diseases caused by these pathogens. Here, we address the current knowledge of prominent host factors required for the flavivirus life-cycle and mechanisms by which they promote infection.
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Affiliation(s)
- Rafael K Campos
- Department of Molecular Genetics and Microbiology, Center for RNA Biology, Duke University, Durham, NC, USA.,Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Mariano A Garcia-Blanco
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA. .,Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore.
| | - Shelton S Bradrick
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA.
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24
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Oliveira LG, Peron JPS. Viral receptors for flaviviruses: Not only gatekeepers. J Leukoc Biol 2019; 106:695-701. [PMID: 31063609 DOI: 10.1002/jlb.mr1118-460r] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/03/2019] [Accepted: 04/10/2019] [Indexed: 12/20/2022] Open
Abstract
Arboviruses have been a huge threat for human health since the discovery of yellow fever virus in 1901. Arboviruses are arthropod born viruses, mainly transmitted by mosquitoes and ticks, responsible for more than thousands of deaths annually. The Flavivirideae family is probably the most clinically relevant, as it is composed of very important agents, such as dengue, yellow fever, West Nile, Japanese encephalitis, and, recently, Zika virus. Intriguingly, despite their structural and genomic similarities, flaviviruses may cause conditions ranging from mild infections with fever, cutaneous rash, and headache, to very severe cases, such as hemorrhagic fever, encephalitis, Guillain-Barré syndrome, and microcephaly. These differences may greatly rely on viral burden, tissue tropism, and mechanisms of immune evasion that may depend on both viral and host genetic factors. Unfortunately, very little is known about the biology of these factors, and how they orchestrate these differences. In this context, viral structural proteins and host cellular receptors may have a great relevance, as their interaction dictates not only viral tissue tropism, but also a plethora on intracellular mechanisms that may greatly account for either failure or success of infection. A great number of viral receptors have been described so far, although there is still a huge gap in understanding their overall role during infection. Here we discuss some important aspects triggered after the interaction of flaviviruses and host membrane receptors, and how they change the overall outcome of the infection.
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Affiliation(s)
- Lilian G Oliveira
- Neuroimmune Interactions Laboratory, Institute of Biomedical Sciences, Department of Immunology, University of Sao Paulo, São Paulo, Brazil
| | - Jean Pierre Schatzmann Peron
- Immunopathology and Alergy PostGraduate Program, School of Medicine, University of São Paulo, Brazil.,Scientific Platform Pasteur, USP, São Paulo, Brazil
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25
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Queiroz A, Pinto IFD, Lima M, Giovanetti M, de Jesus JG, Xavier J, Barreto FK, Canuto GAB, do Amaral HR, de Filippis AMB, Mascarenhas DL, Falcão MB, Santos NP, Azevedo VADC, Yoshinaga MY, Miyamoto S, Alcantara LCJ. Lipidomic Analysis Reveals Serum Alteration of Plasmalogens in Patients Infected With ZIKA Virus. Front Microbiol 2019; 10:753. [PMID: 31031729 PMCID: PMC6474330 DOI: 10.3389/fmicb.2019.00753] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 03/26/2019] [Indexed: 12/14/2022] Open
Abstract
Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the Flavivirus genus of the Flaviviridae family. Since the large outbreaks in French Polynesia in 2013–2014 and in Brazil in 2015, ZIKV has been considered a new public health threat. Similar to other related flavivirus, ZIKV is associated with mild and self-limiting symptoms such as rash, pruritus, prostration, headache, arthralgia, myalgia, conjunctivitis, lower back pain and, when present, a short-term low grade fever. In addition, ZIKV has been implicated in neurological complications such as neonatal microcephaly and Guillain–Barré syndrome in adults. Herein, serum lipidomic analysis was used to identify possible alterations in lipid metabolism triggered by ZIKV infection. Patients who presented virus-like symptoms such as fever, arthralgia, headache, exanthema, myalgia and pruritus were selected as the control group. Our study reveals increased levels of several phosphatidylethanolamine (PE) lipid species in the serum of ZIKV patients, the majority of them plasmenyl-phosphatidylethanolamine (pPE) (or plasmalogens) linked to polyunsaturated fatty acids. Constituting up to 20% of total phospholipids in humans, plasmalogens linked to polyunsaturated fatty acids are particularly enriched in neural membranes of the brain. The biosynthesis of plasmalogens requires functional peroxisomes, which are important sites for viral replication, including ZIKV. Thus, increased levels of plasmalogens in serum of ZIKV infected subjects suggest a link between ZIKV life cycle and peroxisomes. Our data provide important insights into specific host cellular lipids that are likely associated with ZIKV replication and may serve as platform for antiviral strategy against ZIKV.
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Affiliation(s)
- Adriano Queiroz
- Laboratório de Patologia Experimental, Instituto Gonçalo Moniz, Salvador, Brazil
| | | | - Maricélia Lima
- Departamento de Saúde, Universidade Estadual de Feira de Santana, Feira de Santana, Brazil
| | - Marta Giovanetti
- Laboratório de Patologia Experimental, Instituto Gonçalo Moniz, Salvador, Brazil.,Laboratório de Flavivírus, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil
| | | | - Joilson Xavier
- Laboratório de Patologia Experimental, Instituto Gonçalo Moniz, Salvador, Brazil
| | - Fernanda Khouri Barreto
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista, Brazil
| | | | - Helineide Ramos do Amaral
- Núcleo de Pesquisa em Vigilância da Saúde, Universidade Estadual de Feira de Santana, Feira de Santana, Brazil
| | | | | | - Melissa Barreto Falcão
- Secretaria Municipal de Saúde do Município de Feira de Santana, Feira de Santana, Brazil
| | | | | | - Marcos Yukio Yoshinaga
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Sayuri Miyamoto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Luiz Carlos Junior Alcantara
- Laboratório de Patologia Experimental, Instituto Gonçalo Moniz, Salvador, Brazil.,Laboratório de Flavivírus, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil.,Laboratório de Genética Celular e Molecular, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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26
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Glover KKM, Gao A, Zahedi-Amiri A, Coombs KM. Vero Cell Proteomic Changes Induced by Zika Virus Infection. Proteomics 2019; 19:e1800309. [PMID: 30578658 DOI: 10.1002/pmic.201800309] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 12/06/2018] [Indexed: 12/12/2022]
Abstract
The re-emergence and the recent spread of the Zika virus (ZIKV) has raised significant global concerns due to lack of information in patient diagnosis and management. Thus, in addition to gaining more basic information about ZIKV biology, appropriate interventions and management strategies are being sought to control ZIKV-associated diseases and its spread. This study's objective is to identify host cell proteins that are significantly dysregulated during ZIKV infection. SOMAScan, a novel aptamer-based assay, is used to simultaneously screen >1300 host proteins to detect ZIKV-induced host protein dysregulation at multiple time points during infection. A total of 125 Vero cell host proteins, including cytokines such as CXCL11 and CCL5, interferon stimulated gene 15, and translation initiation factors EIF5A and EIF4G2, are significantly dysregulated after ZIKV infection. Bioinformatic analyses of 77 host proteins, that are significantly dysregulated ≥1.25-fold, identify several activated biological processes, including the JAK/STAT, Tec kinase, and complement cascade pathways.
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Affiliation(s)
- Kathleen K M Glover
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, R3E OJ9, Canada.,Manitoba Centre for Proteomics & Systems Biology, Winnipeg, Manitoba, R3E 3P4, Canada
| | - Ang Gao
- Manitoba Centre for Proteomics & Systems Biology, Winnipeg, Manitoba, R3E 3P4, Canada
| | - Ali Zahedi-Amiri
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, R3E OJ9, Canada.,Manitoba Centre for Proteomics & Systems Biology, Winnipeg, Manitoba, R3E 3P4, Canada
| | - Kevin M Coombs
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, R3E OJ9, Canada.,Manitoba Centre for Proteomics & Systems Biology, Winnipeg, Manitoba, R3E 3P4, Canada.,Children's Hospital Research Institute of Manitoba, Buhler Research Centre, Winnipeg, Manitoba, R3E 3P4, Canada
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27
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Rawle RJ, Webster ER, Jelen M, Kasson PM, Boxer SG. pH Dependence of Zika Membrane Fusion Kinetics Reveals an Off-Pathway State. ACS CENTRAL SCIENCE 2018; 4:1503-1510. [PMID: 30555902 PMCID: PMC6276045 DOI: 10.1021/acscentsci.8b00494] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Indexed: 05/20/2023]
Abstract
The recent spread of Zika virus stimulated extensive research on its structure, pathogenesis, and immunology, but mechanistic study of entry has lagged behind, in part due to the lack of a defined reconstituted system. Here, we report Zika membrane fusion measured using a platform that bypasses these barriers, enabling observation of single-virus fusion kinetics without receptor reconstitution. Surprisingly, target membrane binding and low pH are sufficient to trigger viral hemifusion to liposomes containing only neutral lipids. Second, although the extent of hemifusion strongly depends on pH, hemifusion rates are relatively insensitive to pH. Kinetic analysis shows that an off-pathway state is required to capture this pH-dependence and suggests this may be related to viral inactivation. Our surrogate-receptor approach thus yields new understanding of flaviviral entry mechanisms and should be applicable to many emerging viruses.
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Affiliation(s)
- Robert J. Rawle
- Departments of Molecular
Physiology and Biological Physics and of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, United States
| | - Elizabeth R. Webster
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Marta Jelen
- Departments of Molecular
Physiology and Biological Physics and of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, United States
| | - Peter M. Kasson
- Departments of Molecular
Physiology and Biological Physics and of Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, United States
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden 75124
- (P.M.K.) E-mail:
| | - Steven G. Boxer
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
- (S.G.B.) E-mail: . Address: 380
Roth Way, Stanford CA 94305-5012. Phone: 650-723-4442
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28
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Exosomes Exploit the Virus Entry Machinery and Pathway To Transmit Alpha Interferon-Induced Antiviral Activity. J Virol 2018; 92:JVI.01578-18. [PMID: 30282711 DOI: 10.1128/jvi.01578-18] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 09/10/2018] [Indexed: 02/07/2023] Open
Abstract
Alpha interferon (IFN-α) induces the transfer of resistance to hepatitis B virus (HBV) from liver nonparenchymal cells (LNPCs) to hepatocytes via exosomes. However, little is known about the entry machinery and pathway involved in the transmission of IFN-α-induced antiviral activity. In this study, we found that macrophage exosomes uniquely depend on T cell immunoglobulin and mucin receptor 1 (TIM-1), a hepatitis A virus (HAV) receptor, to enter hepatocytes for delivering IFN-α-induced anti-HBV activity. Moreover, two primary endocytic routes for virus infection, clathrin-mediated endocytosis (CME) and macropinocytosis, collaborate to permit exosome entry and anti-HBV activity transfer. Subsequently, lysobisphosphatidic acid (LBPA), an anionic lipid closely related to endosome penetration of virus, facilitates membrane fusion of exosomes in late endosomes/multivesicular bodies (LEs/MVBs) and the accompanying exosomal cargo uncoating. Together, our findings provide comprehensive insights into the transmission route of macrophage exosomes to efficiently deliver IFN-α-induced antiviral substances and highlight the similarities between the entry mechanisms of exosomes and virus.IMPORTANCE Our previous study showed that LNPC-derived exosomes could transmit IFN-α-induced antiviral activity to HBV replicating hepatocytes, but the concrete transmission mechanisms, which include exosome entry and exosomal cargo release, remain unclear. In this study, we found that virus entry machinery and pathway were also applied to exosome-mediated cell-to-cell antiviral activity transfer. Macrophage-derived exosomes distinctively exploit hepatitis A virus receptor for access to hepatocytes. Later, CME and macropinocytosis are utilized by exosomes, followed by exosome-endosome fusion for efficient transfer of IFN-α-induced anti-HBV activity. We believe that understanding the cellular entry pathway of exosomes will be beneficial to designing exosomes as efficient vehicles for antiviral therapy.
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29
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Early Events in Japanese Encephalitis Virus Infection: Viral Entry. Pathogens 2018; 7:pathogens7030068. [PMID: 30104482 PMCID: PMC6161159 DOI: 10.3390/pathogens7030068] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 07/31/2018] [Accepted: 08/06/2018] [Indexed: 12/15/2022] Open
Abstract
Japanese encephalitis virus (JEV), a mosquito-borne zoonotic flavivirus, is an enveloped positive-strand RNA virus that can cause a spectrum of clinical manifestations, ranging from mild febrile illness to severe neuroinvasive disease. Today, several killed and live vaccines are available in different parts of the globe for use in humans to prevent JEV-induced diseases, yet no antivirals are available to treat JEV-associated diseases. Despite the progress made in vaccine research and development, JEV is still a major public health problem in southern, eastern, and southeastern Asia, as well as northern Oceania, with the potential to become an emerging global pathogen. In viral replication, the entry of JEV into the cell is the first step in a cascade of complex interactions between the virus and target cells that is required for the initiation, dissemination, and maintenance of infection. Because this step determines cell/tissue tropism and pathogenesis, it is a promising target for antiviral therapy. JEV entry is mediated by the viral glycoprotein E, which binds virions to the cell surface (attachment), delivers them to endosomes (endocytosis), and catalyzes the fusion between the viral and endosomal membranes (membrane fusion), followed by the release of the viral genome into the cytoplasm (uncoating). In this multistep process, a collection of host factors are involved. In this review, we summarize the current knowledge on the viral and cellular components involved in JEV entry into host cells, with an emphasis on the initial virus-host cell interactions on the cell surface.
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30
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Rinkenberger N, Schoggins JW. Mucolipin-2 Cation Channel Increases Trafficking Efficiency of Endocytosed Viruses. mBio 2018; 9:e02314-17. [PMID: 29382735 PMCID: PMC5790917 DOI: 10.1128/mbio.02314-17] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 01/03/2018] [Indexed: 12/26/2022] Open
Abstract
Receptor-mediated endocytosis is a cellular process commonly hijacked by viruses to enter cells. The stages of entry are well described for certain viruses, but the host factors that mediate each step are less well characterized. We previously identified endosomal cation channel mucolipin-2 (MCOLN2) as a host factor that promotes viral infection. Here, we assign a role for MCOLN2 in modulating viral entry. We show that MCOLN2 specifically promotes viral vesicular trafficking and subsequent escape from endosomal compartments. This mechanism requires channel activity, occurs independently of antiviral signaling, and broadly applies to enveloped RNA viruses that require transport to late endosomes for infection, including influenza A virus, yellow fever virus, and Zika virus. We further identify a rare allelic variant of human MCOLN2 that has a loss-of-function phenotype with respect to viral enhancement. These findings establish a mechanistic link between an endosomal cation channel and late stages of viral entry.IMPORTANCE Viruses must co-opt cellular processes to complete their life cycle. To enter cells, viruses frequently take advantage of cellular receptor-mediated endocytosis pathways. A growing number of host proteins are implicated in these viral uptake pathways. Here, we describe a new role for the gated cation channel MCOLN2 in viral entry. This endosomal protein modulates viral entry by enhancing the efficiency of viral trafficking through the endosomal system. Thus, MCOLN2-mediated enhancement of infection may represent a key vulnerability in the viral life cycle that could be targeted for therapeutic intervention.
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Affiliation(s)
- Nicholas Rinkenberger
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - John W Schoggins
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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31
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Structure of tick-borne encephalitis virus and its neutralization by a monoclonal antibody. Nat Commun 2018; 9:436. [PMID: 29382836 PMCID: PMC5789857 DOI: 10.1038/s41467-018-02882-0] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 01/03/2018] [Indexed: 02/04/2023] Open
Abstract
Tick-borne encephalitis virus (TBEV) causes 13,000 cases of human meningitis and encephalitis annually. However, the structure of the TBEV virion and its interactions with antibodies are unknown. Here, we present cryo-EM structures of the native TBEV virion and its complex with Fab fragments of neutralizing antibody 19/1786. Flavivirus genome delivery depends on membrane fusion that is triggered at low pH. The virion structure indicates that the repulsive interactions of histidine side chains, which become protonated at low pH, may contribute to the disruption of heterotetramers of the TBEV envelope and membrane proteins and induce detachment of the envelope protein ectodomains from the virus membrane. The Fab fragments bind to 120 out of the 180 envelope glycoproteins of the TBEV virion. Unlike most of the previously studied flavivirus-neutralizing antibodies, the Fab fragments do not lock the E-proteins in the native-like arrangement, but interfere with the process of virus-induced membrane fusion. The tick-borne encephalitis virus (TBEV) causes thousands of cases of meningitis and encephalitis annually. Here, the authors describe a cryo-EM structure of the TBEV virion bound by Fab fragments of the neutralizing antibody 19/1786, revealing a mechanism whereby this antibody prevents virus membrane fusion.
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32
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Yuan S, Zhang ZW, Li ZL. Trehalose May Decrease the Transmission of Zika Virus to the Fetus by Activating Degradative Autophagy. Front Cell Infect Microbiol 2017; 7:402. [PMID: 28932709 PMCID: PMC5592200 DOI: 10.3389/fcimb.2017.00402] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 08/25/2017] [Indexed: 01/14/2023] Open
Affiliation(s)
- Shu Yuan
- College of Resources, Sichuan Agricultural UniversityChengdu, China
| | - Zhong-Wei Zhang
- College of Resources, Sichuan Agricultural UniversityChengdu, China
| | - Zi-Lin Li
- Department of Cardiovascular Surgery, Xijing Hospital, Medical University of the Air ForceXi'an, China
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33
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Antiviral Activity of Nordihydroguaiaretic Acid and Its Derivative Tetra- O-Methyl Nordihydroguaiaretic Acid against West Nile Virus and Zika Virus. Antimicrob Agents Chemother 2017; 61:AAC.00376-17. [PMID: 28507114 DOI: 10.1128/aac.00376-17] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/09/2017] [Indexed: 01/18/2023] Open
Abstract
Flaviviruses are positive-strand RNA viruses distributed all over the world that infect millions of people every year and for which no specific antiviral agents have been approved. These viruses include the mosquito-borne West Nile virus (WNV), which is responsible for outbreaks of meningitis and encephalitis. Considering that nordihydroguaiaretic acid (NDGA) has been previously shown to inhibit the multiplication of the related dengue virus and hepatitis C virus, we have evaluated the effect of NDGA, and its methylated derivative tetra-O-methyl nordihydroguaiaretic acid (M4N), on the infection of WNV. Both compounds inhibited the infection of WNV, likely by impairing viral replication. Since flavivirus multiplication is highly dependent on host cell lipid metabolism, the antiviral effect of NDGA has been previously related to its ability to disturb the lipid metabolism, probably by interfering with the sterol regulatory element-binding proteins (SREBP) pathway. Remarkably, we observed that other structurally unrelated inhibitors of the SREBP pathway, such as PF-429242 and fatostatin, also reduced WNV multiplication, supporting that the SREBP pathway may constitute a druggable target suitable for antiviral intervention against flavivirus infection. Moreover, treatment with NDGA, M4N, PF-429242, and fatostatin also inhibited the multiplication of the mosquito-borne flavivirus Zika virus (ZIKV), which has been recently associated with birth defects (microcephaly) and neurological disorders. Our results point to SREBP inhibitors, such as NDGA and M4N, as potential candidates for further antiviral development against medically relevant flaviviruses.
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34
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Liu X, Ouyang T, Ouyang H, Ren L. Single particle labeling of RNA virus in live cells. Virus Res 2017; 237:14-21. [PMID: 28506790 DOI: 10.1016/j.virusres.2017.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 05/10/2017] [Accepted: 05/10/2017] [Indexed: 12/17/2022]
Abstract
Real-time and visual tracking of viral infection is crucial for elucidating the infectious and pathogenesis mechanisms. To track the virus successfully, an efficient labeling method is necessary. In this review, we first discuss the practical labeling techniques for virus tracking in live cells. We then describe the current knowledge of interactions between RNA viruses (especially influenza viruses, immunodeficiency viruses, and Flaviviruses) and host cellular structures, obtained using single particle labeling techniques combined with real-time fluorescence microscopy. Single particle labeling provides an easy system for understanding the RNA virus life cycle.
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Affiliation(s)
- Xiaohui Liu
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, China
| | - Ting Ouyang
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, China
| | - Hongsheng Ouyang
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, China
| | - Linzhu Ren
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin 130062, China.
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35
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Desai TM, Marin M, Mason C, Melikyan GB. pH regulation in early endosomes and interferon-inducible transmembrane proteins control avian retrovirus fusion. J Biol Chem 2017; 292:7817-7827. [PMID: 28341742 DOI: 10.1074/jbc.m117.783878] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/22/2017] [Indexed: 01/09/2023] Open
Abstract
Enveloped viruses infect host cells by fusing their membranes with those of the host cell, a process mediated by viral glycoproteins upon binding to cognate host receptors or entering into acidic intracellular compartments. Whereas the effect of receptor density on viral infection has been well studied, the role of cell type-specific factors/processes, such as pH regulation, has not been characterized in sufficient detail. Here, we examined the effects of cell-extrinsic factors (buffer environment) and cell-intrinsic factors (interferon-inducible transmembrane proteins, IFITMs), on the pH regulation in early endosomes and on the efficiency of acid-dependent fusion of the avian sarcoma and leukosis virus (ASLV), with endosomes. First, we found that a modest elevation of external pH can raise the pH in early endosomes in a cell type-dependent manner and thereby delay the acid-induced fusion of endocytosed ASLV. Second, we observed a cell type-dependent delay between the low pH-dependent and temperature-dependent steps of viral fusion, consistent with the delayed enlargement of the fusion pore. Third, ectopic expression of IFITMs, known to potently block influenza virus fusion with late compartments, was found to only partially inhibit ASLV fusion with early endosomes. Interestingly, IFITM expression promoted virus uptake and the acidification of endosomal compartments, resulting in an accelerated fusion rate when driven by the glycosylphosphatidylinositol-anchored, but not by the transmembrane isoform of the ASLV receptor. Collectively, these results highlight the role of cell-extrinsic and cell-intrinsic factors in regulating the efficiency and kinetics of virus entry and fusion with target cells.
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Affiliation(s)
- Tanay M Desai
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and
| | - Mariana Marin
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and
| | - Caleb Mason
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and
| | - Gregory B Melikyan
- From the Division of Pediatric Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia 30322 and .,the Children's Healthcare of Atlanta, Atlanta, Georgia 300322
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36
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Zhang ZW, Li ZL, Yuan S. The Role of Secretory Autophagy in Zika Virus Transfer through the Placental Barrier. Front Cell Infect Microbiol 2017; 6:206. [PMID: 28119857 PMCID: PMC5220013 DOI: 10.3389/fcimb.2016.00206] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 12/22/2016] [Indexed: 01/12/2023] Open
Abstract
Recent studies indicated that the Zika virus genome could be detected in the amniotic fluid and the fetal brain, which confirms that the virus can cross the placental barrier. Secretory autophagy or exosome pathways may participate in this virus transfer. Autophagy modulators regulate autophagosome formation or membrane fusion with lysosomal vesicles and therefore inhibit viral nucleocapsid releasing or virus transfer to the fetus hypothetically. However, some autophagy modulators may enhance virus replication. Autophagy inhibitors may arrest placental development; while exaggeration of autophagy in human placenta may be associated with the fetal growth restriction. Therefore, autophagy modulators should be used carefully due to their complex clinical effects. Alternatively, exosome-specific inhibitors might be also considered, although their safety of both maternal and fetal conditions must be carefully assessed before any advancement to human clinical trials.
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Affiliation(s)
- Zhong-Wei Zhang
- College of Resources, Sichuan Agricultural University Chengdu, China
| | - Zi-Lin Li
- General Hospital of Lanzhou Military Region Lanzhou, China
| | - Shu Yuan
- College of Resources, Sichuan Agricultural University Chengdu, China
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37
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Martín-Acebes MA, Vázquez-Calvo Á, Saiz JC. Lipids and flaviviruses, present and future perspectives for the control of dengue, Zika, and West Nile viruses. Prog Lipid Res 2016; 64:123-137. [PMID: 27702593 DOI: 10.1016/j.plipres.2016.09.005] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 08/17/2016] [Accepted: 09/16/2016] [Indexed: 02/06/2023]
Abstract
Flaviviruses are emerging arthropod-borne pathogens that cause life-threatening diseases such as yellow fever, dengue, West Nile encephalitis, tick-borne encephalitis, Kyasanur Forest disease, tick-borne encephalitis, or Zika disease. This viral genus groups >50 viral species of small enveloped plus strand RNA virus that are phylogenetically closely related to hepatitis C virus. Importantly, the flavivirus life cycle is intimately associated to host cell lipids. Along this line, flaviviruses rearrange intracellular membranes from the endoplasmic-reticulum of the infected cells to develop adequate platforms for viral replication and particle biogenesis. Moreover, flaviviruses dramatically orchestrate a profound reorganization of the host cell lipid metabolism to create a favorable environment for viral multiplication. Consistently, recent work has shown the importance of specific lipid classes in flavivirus infections. For instances, fatty acid synthesis is linked to viral replication, phosphatidylserine and phosphatidylethanolamine are involved on the entry of flaviviruses, sphingolipids (ceramide and sphingomyelin) play a key role on virus assembly and pathogenesis, and cholesterol is essential for innate immunity evasion in flavivirus-infected cells. Here, we revise the current knowledge on the interactions of the flaviviruses with the cellular lipid metabolism to identify potential targets for future antiviral development aimed to combat these relevant health-threatening pathogens.
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Affiliation(s)
- Miguel A Martín-Acebes
- Department of Biotechnology, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Carretera de A Coruña km 7.5, 28040 Madrid, Spain.
| | - Ángela Vázquez-Calvo
- Department of Biotechnology, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Carretera de A Coruña km 7.5, 28040 Madrid, Spain
| | - Juan-Carlos Saiz
- Department of Biotechnology, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Carretera de A Coruña km 7.5, 28040 Madrid, Spain
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Abstract
Viruses have evolved many mechanisms by which to evade and subvert the immune system to ensure survival and persistence. However, for each method undertaken by the immune system for pathogen removal, there is a counteracting mechanism utilized by pathogens. The new and emerging role of microvesicles in immune intercellular communication and function is no different. Viruses across many different families have evolved to insert viral components in exosomes, a subtype of microvesicle, with many varying downstream effects. When assessed cumulatively, viral antigens in exosomes increase persistence through cloaking viral genomes, decoying the immune system, and even by increasing viral infection in uninfected cells. Exosomes therefore represent a source of viral antigen that can be used as a biomarker for disease and targeted for therapy in the control and eradication of these disorders. With the rise in the persistence of new and reemerging viruses like Ebola and Zika, exploring the role of exosomes become more important than ever.
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Affiliation(s)
- Monique R Anderson
- National Institutes of Health, National Institute of Neurological Disorders and Stroke, Neuroimmunology Branch, Viral Immunology Section, Bethesda, MD, 20892, USA.
- Department of Pathology Molecular and Cellular Basis of Disease Graduate Program, University of Virginia School of Medicine, Charlottesville, VA, 22903, USA.
| | - Fatah Kashanchi
- George Mason University, National Center for Biodefense and Infectious Disease, Laboratory of Molecular Virology, Manassas, VA, 20110, USA
| | - Steven Jacobson
- National Institutes of Health, National Institute of Neurological Disorders and Stroke, Neuroimmunology Branch, Viral Immunology Section, Bethesda, MD, 20892, USA
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White JM, Whittaker GR. Fusion of Enveloped Viruses in Endosomes. Traffic 2016; 17:593-614. [PMID: 26935856 PMCID: PMC4866878 DOI: 10.1111/tra.12389] [Citation(s) in RCA: 282] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 02/25/2016] [Accepted: 02/25/2016] [Indexed: 12/12/2022]
Abstract
Ari Helenius launched the field of enveloped virus fusion in endosomes with a seminal paper in the Journal of Cell Biology in 1980. In the intervening years, a great deal has been learned about the structures and mechanisms of viral membrane fusion proteins as well as about the endosomes in which different enveloped viruses fuse and the endosomal cues that trigger fusion. We now recognize three classes of viral membrane fusion proteins based on structural criteria and four mechanisms of fusion triggering. After reviewing general features of viral membrane fusion proteins and viral fusion in endosomes, we delve into three characterized mechanisms for viral fusion triggering in endosomes: by low pH, by receptor binding plus low pH and by receptor binding plus the action of a protease. We end with a discussion of viruses that may employ novel endosomal fusion‐triggering mechanisms. A key take‐home message is that enveloped viruses that enter cells by fusing in endosomes traverse the endocytic pathway until they reach an endosome that has all of the environmental conditions (pH, proteases, ions, intracellular receptors and lipid composition) to (if needed) prime and (in all cases) trigger the fusion protein and to support membrane fusion.
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Affiliation(s)
- Judith M White
- Department of Cell Biology, University of Virginia, Charlottesville, VA, USA
| | - Gary R Whittaker
- Department of Microbiology & Immunology, Cornell University, Ithaca, NY, USA
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40
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Klaus JP, Botten J. Highly Sensitive Assay for Measurement of Arenavirus-cell Attachment. J Vis Exp 2016:e53682. [PMID: 26966937 DOI: 10.3791/53682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Arenaviruses are a family of enveloped RNA viruses that cause severe human disease. The first step in the arenavirus life cycle is attachment of viral particles to host cells. While virus-cell attachment can be measured through the use of virions labeled with biotin, radioactive isotopes, or fluorescent dyes, these approaches typically require high multiplicities of infection (MOI) to enable detection of bound virus. We describe a quantitative (q)RT-PCR-based assay that measures Junin virus strain Candid 1 attachment via quantitation of virion-packaged viral genomic RNA. This assay has several advantages including its extreme sensitivity and ability to measure attachment over a large dynamic range of MOIs without the need to purify or label input virus. Importantly, this approach can be easily tailored for use with other viruses through the use of virus-specific qRT-PCR reagents. Further, this assay can be modified to permit measurement of particle endocytosis and genome uncoating. In conclusion, we describe a simple, yet robust assay for highly sensitive measurement of arenavirus-cell attachment.
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Affiliation(s)
- Joseph P Klaus
- Department of Medicine, Division of Immunobiology, University of Vermont
| | - Jason Botten
- Department of Medicine, Division of Immunobiology, University of Vermont; Department of Microbiology & Molecular Genetics, University of Vermont;
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Markosyan RM, Miao C, Zheng YM, Melikyan GB, Liu SL, Cohen FS. Induction of Cell-Cell Fusion by Ebola Virus Glycoprotein: Low pH Is Not a Trigger. PLoS Pathog 2016; 12:e1005373. [PMID: 26730950 PMCID: PMC4711667 DOI: 10.1371/journal.ppat.1005373] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 12/08/2015] [Indexed: 12/11/2022] Open
Abstract
Ebola virus (EBOV) is a highly pathogenic filovirus that causes hemorrhagic fever in humans and animals. Currently, how EBOV fuses its envelope membrane within an endosomal membrane to cause infection is poorly understood. We successfully measure cell-cell fusion mediated by the EBOV fusion protein, GP, assayed by the transfer of both cytoplasmic and membrane dyes. A small molecule fusion inhibitor, a neutralizing antibody, as well as mutations in EBOV GP known to reduce viral infection, all greatly reduce fusion. By monitoring redistribution of small aqueous dyes between cells and by electrical capacitance measurements, we discovered that EBOV GP-mediated fusion pores do not readily enlarge—a marked difference from the behavior of other viral fusion proteins. EBOV GP must be cleaved by late endosome-resident cathepsins B or L in order to become fusion-competent. Cleavage of cell surface-expressed GP appears to occur in endosomes, as evidenced by the fusion block imposed by cathepsin inhibitors, agents that raise endosomal pH, or an inhibitor of anterograde trafficking. Treating effector cells with a recombinant soluble cathepsin B or thermolysin, which cleaves GP into an active form, increases the extent of fusion, suggesting that a fraction of surface-expressed GP is not cleaved. Whereas the rate of fusion is increased by a brief exposure to acidic pH, fusion does occur at neutral pH. Importantly, the extent of fusion is independent of external pH in experiments in which cathepsin activity is blocked and EBOV GP is cleaved by thermolysin. These results imply that low pH promotes fusion through the well-known pH-dependent activity of cathepsins; fusion induced by cleaved EBOV GP is a process that is fundamentally independent of pH. The cell-cell fusion system has revealed some previously unappreciated features of EBOV entry, which could not be readily elucidated in the context of endosomal entry. The devastation and transmissibility of Ebola virus (EBOV) are well known. However, the manner in which EBOV enters host cells through endosomal membrane remains elusive. Here, we have developed a convenient experimental system to mimic EBOV fusion in endosomes: cells expressing the fusion protein of EBOV, GP, on their surface are fused to target cells. This system exhibits the known key properties of EBOV fusion. We show that the pH-dependence of EBOV fusion is caused by the pH-dependence of cathepsins, proteases known to cleave EBOV GP into a fusion-competent form. We demonstrate that the fusion activity of this cleaved form is independent of pH. We further show that the enlargement of the fusion pore created by EBOV GP is unusually slow in reaching sizes necessary to pass EBOV’s genome—this is atypical of virally created fusion pores. This cell-cell fusion system should provide a useful platform for developing drugs against EBOV infection.
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Affiliation(s)
- Ruben M. Markosyan
- Rush University Medical Center, Department of Molecular Biophysics and Physiology, Chicago, Illinois, United States of America
| | - Chunhui Miao
- University of Missouri School of Medicine, Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, Columbia, Missouri, United States of America
| | - Yi-Min Zheng
- University of Missouri School of Medicine, Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, Columbia, Missouri, United States of America
| | - Gregory B. Melikyan
- Emory University Medical School, Department of Pediatrics, Infectious Diseases, Atlanta, Georgia, United States of America
| | - Shan-Lu Liu
- University of Missouri School of Medicine, Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, Columbia, Missouri, United States of America
- * E-mail: (SLL); (FSC)
| | - Fredric S. Cohen
- Rush University Medical Center, Department of Molecular Biophysics and Physiology, Chicago, Illinois, United States of America
- * E-mail: (SLL); (FSC)
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Abstract
Metabolism refers to the chemical reactions that occur in living cells, and the reactants and products of these reactions compose the metabolome. The lipidome is comprised by hydrophobic metabolites and includes several broad classes of structurally diverse molecules. Lipids supplied by the host cell are required for many viral processes, and many if not all viruses have evolved mechanisms to perturb host metabolism to promote viral replication. This chapter provides background and a framework for examining the role of lipid metabolites in viral processes and rational attempts to target host metabolism as an antiviral strategy.
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Villareal VA, Rodgers MA, Costello DA, Yang PL. Targeting host lipid synthesis and metabolism to inhibit dengue and hepatitis C viruses. Antiviral Res 2015; 124:110-21. [PMID: 26526588 DOI: 10.1016/j.antiviral.2015.10.013] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 10/08/2015] [Accepted: 10/11/2015] [Indexed: 12/16/2022]
Abstract
Lipids are necessary for every step in the replication cycle of hepatitis C virus (HCV) and dengue virus (DENV), members of the family Flaviviridae. Recent studies have demonstrated that discrete steps in the replication cycles of these viruses can be inhibited by pharmacological agents that target host factors mediating lipid synthesis, metabolism, trafficking, and signal transduction. Despite this, targeting host lipid metabolism and trafficking as an antiviral strategy by blockade of entire pathways may be limited due to host toxicity. Knowledge of the molecular details of lipid structure and function in replication and the mechanisms whereby specific lipids are generated and trafficked to the relevant sites may enable more targeted antiviral strategies without global effects on the host cell. In this review, we discuss lipids demonstrated to be critical to the replication cycles of HCV and DENV and highlight potential areas for anti-viral development. This review article forms part of a symposium on flavivirus drug discovery in Antiviral Research.
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Affiliation(s)
- Valerie A Villareal
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | - Mary A Rodgers
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | - Deirdre A Costello
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
| | - Priscilla L Yang
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA.
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44
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Alenquer M, Amorim MJ. Exosome Biogenesis, Regulation, and Function in Viral Infection. Viruses 2015; 7:5066-83. [PMID: 26393640 PMCID: PMC4584306 DOI: 10.3390/v7092862] [Citation(s) in RCA: 253] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 08/31/2015] [Accepted: 09/07/2015] [Indexed: 12/16/2022] Open
Abstract
Exosomes are extracellular vesicles released upon fusion of multivesicular bodies (MVBs) with the cellular plasma membrane. They originate as intraluminal vesicles (ILVs) during the process of MVB formation. Exosomes were shown to contain selectively sorted functional proteins, lipids, and RNAs, mediating cell-to-cell communications and hence playing a role in the physiology of the healthy and diseased organism. Challenges in the field include the identification of mechanisms sustaining packaging of membrane-bound and soluble material to these vesicles and the understanding of the underlying processes directing MVBs for degradation or fusion with the plasma membrane. The investigation into the formation and roles of exosomes in viral infection is in its early years. Although still controversial, exosomes can, in principle, incorporate any functional factor, provided they have an appropriate sorting signal, and thus are prone to viral exploitation. This review initially focuses on the composition and biogenesis of exosomes. It then explores the regulatory mechanisms underlying their biogenesis. Exosomes are part of the endocytic system, which is tightly regulated and able to respond to several stimuli that lead to alterations in the composition of its sub-compartments. We discuss the current knowledge of how these changes affect exosomal release. We then summarize how different viruses exploit specific proteins of endocytic sub-compartments and speculate that it could interfere with exosome function, although no direct link between viral usage of the endocytic system and exosome release has yet been reported. Many recent reports have ascribed functions to exosomes released from cells infected with a variety of animal viruses, including viral spread, host immunity, and manipulation of the microenvironment, which are discussed. Given the ever-growing roles and importance of exosomes in viral infections, understanding what regulates their composition and levels, and defining their functions will ultimately provide additional insights into the virulence and persistence of infections.
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Affiliation(s)
- Marta Alenquer
- Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2778-156 Oeiras, Portugal.
| | - Maria João Amorim
- Cell Biology of Viral Infection Lab, Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2778-156 Oeiras, Portugal.
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45
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Espósito DLA, Nguyen JB, DeWitt DC, Rhoades E, Modis Y. Physico-chemical requirements and kinetics of membrane fusion of flavivirus-like particles. J Gen Virol 2015; 96:1702-11. [PMID: 25740960 PMCID: PMC4635454 DOI: 10.1099/vir.0.000113] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Flaviviruses deliver their RNA genome into the host-cell cytoplasm by fusing their lipid envelope with a cellular membrane. Expression of the flavivirus pre-membrane and envelope glycoprotein genes in the absence of other viral genes results in the spontaneous assembly and secretion of virus-like particles (VLPs) with membrane fusion activity. Here, we examined the physico-chemical requirements for membrane fusion of VLPs from West Nile and Japanese encephalitis viruses. In a bulk fusion assay, optimal hemifusion (or lipid mixing) efficiencies were observed at 37 °C. Fusion efficiency increased with decreasing pH; half-maximal hemifusion was attained at pH 5.6. The anionic lipids bis(monoacylglycero)phosphate and phosphatidylinositol-3-phosphate, when present in the target membrane, significantly enhanced fusion efficiency, consistent with the emerging model that flaviviruses fuse with intermediate-to-late endosomal compartments, where these lipids are most abundant. In a single-particle fusion assay, VLPs catalysed membrane hemifusion, tracked as lipid mixing with the cellular membrane, on a timescale of 7–20 s after acidification. Lipid mixing kinetics suggest that hemifusion is a kinetically complex, multistep process.
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Affiliation(s)
- Danillo L A Espósito
- 1Department of Molecular Biophysics & Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520, USA
| | - Jennifer B Nguyen
- 1Department of Molecular Biophysics & Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520, USA
| | - David C DeWitt
- 1Department of Molecular Biophysics & Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520, USA
| | - Elizabeth Rhoades
- 1Department of Molecular Biophysics & Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520, USA 2Department of Physics, Yale University, New Haven, CT 06520, USA
| | - Yorgo Modis
- 1Department of Molecular Biophysics & Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520, USA
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46
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Bruni D, Chazal M, Sinigaglia L, Chauveau L, Schwartz O, Desprès P, Jouvenet N. Viral entry route determines how human plasmacytoid dendritic cells produce type I interferons. Sci Signal 2015; 8:ra25. [PMID: 25737587 DOI: 10.1126/scisignal.aaa1552] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Although plasmacytoid dendritic cells (pDCs) represent a rare immune cell type, they are the most important source of type I interferons (IFNs) upon viral infection. Phagocytosed RNA viruses and RNA virus-infected cells are detected by pDCs with the endosomal pattern recognition receptor (PRR) toll-like receptor 7 (TLR7). We showed that replication of the yellow fever live vaccine YF-17D in human pDCs and pDC-like cell lines stimulated type I IFN production through RIG-I (retinoic acid-inducible gene I), a member of the RIG-I-like receptor (RLR) family of cytosolic PRRs. Thus, human pDCs sense replicative viral RNA. In contrast, direct contact between pDCs and YF-17D-infected cells stimulated a TLR7-dependent, viral replication-independent production of type I IFN. We also showed that the RLR pathway was dampened by the activities of interleukin-1 receptor-associated kinases 1 and 4 (IRAK1 and IRAK4), which are downstream effectors of the TLR7 pathway, suggesting that both kinases play opposing roles downstream of specific PRRs. Together, these data suggest that a virus can stimulate either TLR or RLR signaling in the same cell, depending on how its nucleic acid content is delivered.
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Affiliation(s)
- Daniela Bruni
- Department of Virology, Viral Genomics and Vaccination, UMR CNRS 3569, Pasteur Institute, 75015 Paris, France
| | - Maxime Chazal
- Department of Virology, Viral Genomics and Vaccination, UMR CNRS 3569, Pasteur Institute, 75015 Paris, France
| | - Laura Sinigaglia
- Department of Virology, Viral Genomics and Vaccination, UMR CNRS 3569, Pasteur Institute, 75015 Paris, France
| | - Lise Chauveau
- Department of Virology, Virus and Immunity, UMR CNRS 3569, Pasteur Institute, 75015 Paris, France
| | - Olivier Schwartz
- Department of Virology, Virus and Immunity, UMR CNRS 3569, Pasteur Institute, 75015 Paris, France
| | - Philippe Desprès
- Department of Infection and Epidemiology, Pasteur Institute, 75015 Paris, France. UMR U1187, Processus Infectieux en Milieu Insulaire Tropicale (I2T team), Cyclotron Réunion Océan Indien, 97490 Saint-Denis, La Reunion, France
| | - Nolwenn Jouvenet
- Department of Virology, Viral Genomics and Vaccination, UMR CNRS 3569, Pasteur Institute, 75015 Paris, France.
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47
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Cruz-Oliveira C, Freire JM, Conceição TM, Higa LM, Castanho MARB, Da Poian AT. Receptors and routes of dengue virus entry into the host cells. FEMS Microbiol Rev 2014; 39:155-70. [PMID: 25725010 DOI: 10.1093/femsre/fuu004] [Citation(s) in RCA: 213] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Dengue is the most prevalent arthropod-borne viral disease, caused by dengue virus, a member of the Flaviviridae family. Its worldwide incidence is now a major health problem, with 2.5 billion people living in risk areas. In this review, we integrate the structural rearrangements of each viral protein and their functions in all the steps of virus entry into the host cells. We describe in detail the putative receptors and attachment factors in mammalian and mosquito cells, and the recognition of viral immunocomplexes via Fcγ receptor in immune cells. We also discuss that virus internalization might occur through distinct entry pathways, including clathrin-mediated or non-classical clathrin-independent endocytosis, depending on the host cell and virus serotype or strain. The implications of viral maturation in virus entry are also explored. Finally, we discuss the mechanisms of viral genome access to the cytoplasm. This includes the role of low pH-induced conformational changes in the envelope protein that mediate membrane fusion, and original insights raised by our recent work that supports the hypothesis that capsid protein would also be an active player in this process, acting on viral genome translocation into the cytoplasm.
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Affiliation(s)
- Christine Cruz-Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - João Miguel Freire
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Thaís M Conceição
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - Luiza M Higa
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - Miguel A R B Castanho
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisbon, Portugal
| | - Andrea T Da Poian
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
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48
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Dubé M, Rey FA, Kielian M. Rubella virus: first calcium-requiring viral fusion protein. PLoS Pathog 2014; 10:e1004530. [PMID: 25474548 PMCID: PMC4256232 DOI: 10.1371/journal.ppat.1004530] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 10/20/2014] [Indexed: 12/22/2022] Open
Abstract
Rubella virus (RuV) infection of pregnant women can cause fetal death, miscarriage, or severe fetal malformations, and remains a significant health problem in much of the underdeveloped world. RuV is a small enveloped RNA virus that infects target cells by receptor-mediated endocytosis and low pH-dependent membrane fusion. The structure of the RuV E1 fusion protein was recently solved in its postfusion conformation. RuV E1 is a member of the class II fusion proteins and is structurally related to the alphavirus and flavivirus fusion proteins. Unlike the other known class II fusion proteins, however, RuV E1 contains two fusion loops, with a metal ion complexed between them by the polar residues N88 and D136. Here we demonstrated that RuV infection specifically requires Ca2+ during virus entry. Other tested cations did not substitute. Ca2+ was not required for virus binding to cell surface receptors, endocytic uptake, or formation of the low pH-dependent E1 homotrimer. However, Ca2+ was required for low pH-triggered E1 liposome insertion, virus fusion and infection. Alanine substitution of N88 or D136 was lethal. While the mutant viruses were efficiently assembled and endocytosed by host cells, E1-membrane insertion and fusion were specifically blocked. Together our data indicate that RuV E1 is the first example of a Ca2+-dependent viral fusion protein and has a unique membrane interaction mechanism. Rubella virus (RuV) is a small enveloped RNA virus causing mild disease in children. However, infection of pregnant women can produce fetal death or congenital rubella syndrome, a constellation of severe birth defects including cataracts, hearing loss, heart disease and developmental delays. While vaccination has greatly reduced disease in the developed world, rubella remains prevalent in developing countries and other undervaccinated populations. RuV infects cells by endocytic uptake and a low pH-triggered membrane fusion reaction mediated by the viral E1 protein. The postfusion structure of E1 revealed a metal ion complexed at the membrane-interacting tip of the protein. Here we demonstrated that RuV infection and fusion are completely dependent on calcium, which could not be replaced functionally by any other metal that was tested. In the absence of calcium, RuV entry and low pH-conformational changes were unchanged, but E1's interaction with the target membrane was specifically blocked. Mutations of the calcium-binding residues in E1 caused a similar inhibition of E1 membrane interaction, fusion and infection. Thus, RuV E1 is the first known example of a calcium-dependent virus fusion protein.
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Affiliation(s)
- Mathieu Dubé
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Felix A. Rey
- Unité de Virologie Structurale, Institut Pasteur and CNRS UMR 3569, Paris, France
| | - Margaret Kielian
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York, United States of America
- * E-mail:
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49
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Affiliation(s)
- Benjamin Podbilewicz
- Department of Biology, Technion–Israel Institute of Technology, Haifa 32000, Israel;
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50
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Moller-Tank S, Maury W. Phosphatidylserine receptors: enhancers of enveloped virus entry and infection. Virology 2014; 468-470:565-580. [PMID: 25277499 PMCID: PMC4252826 DOI: 10.1016/j.virol.2014.09.009] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Revised: 07/15/2014] [Accepted: 09/08/2014] [Indexed: 12/23/2022]
Abstract
A variety of both RNA and DNA viruses envelop their capsids in a lipid bilayer. One of the more recently appreciated benefits this envelope is incorporation of phosphatidylserine (PtdSer). Surface exposure of PtdSer disguises viruses as apoptotic bodies; tricking cells into engulfing virions. This mechanism is termed apoptotic mimicry. Several PtdSer receptors have been identified to enhance virus entry and we have termed this group of proteins PtdSer-mediated virus entry enhancing receptors or PVEERs. These receptors enhance entry of a range of enveloped viruses. Internalization of virions by PVEERs provides a broad mechanism of entry with little investment by the virus itself. PVEERs may allow some viruses to attach to cells, thereby making viral glycoprotein/cellular receptor interactions more probable. Alternatively, other viruses may rely entirely on PVEERs for internalization into endosomes. This review provides an overview of PtdSer receptors that serve as PVEERs and the biology behind virion/PVEER interaction. Phosphatidylserine (PtdSer) receptors can mediate entry of enveloped viruses. PtdSer is present on the outer leaflet of the virion envelope. PtdSer receptors are expressed on a variety of primary cells and cell lines. Characteristics of PtdSer receptors that mediate virus entry are defined.
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Affiliation(s)
- Sven Moller-Tank
- Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA
| | - Wendy Maury
- Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA.
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