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Cioffi MD, Sharma T, Motsa BB, Bhattarai N, Gerstman BS, Stahelin RV, Chapagain PP. Ebola Virus Matrix Protein VP40 Single Mutations G198R and G201R Significantly Enhance Plasma Membrane Localization. J Phys Chem B 2024. [PMID: 39326870 DOI: 10.1021/acs.jpcb.4c02700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2024]
Abstract
Viral proteins frequently undergo single or multiple amino acid mutations during replication, which can significantly alter their functionality. The Ebola virus matrix protein VP40 is multifunctional but primarily responsible for creating the viral envelope by binding to the inner leaflet of the host cell plasma membrane (PM). Changes to the VP40 surface cationic charge via mutations can influence PM interactions, resulting in altered viral assembly and budding. A recent mutagenesis study evaluated the effects of several mutations and found that mutations G198R and G201R enhanced VP40 assembly at the PM and virus-like particle budding. These two mutations lie in the loop region of the C-terminal domain (CTD), which directly interacts with the PM. To understand the role of these mutations in PM localization at the molecular level, we performed both all-atom and coarse-grained molecular dynamics simulations using a dimer-dimer configuration of VP40, which contains the CTD-CTD interface. Our studies indicate that the location of mutations on the outer surface of the CTD regions can lead to changes in membrane binding orientation and degree of membrane penetration. Direct PI(4,5)P2 interactions with the mutated residues seem to further stabilize and pull VP40 into the PM, thereby enhancing interactions with numerous amino acids that were otherwise infrequently or completely inaccessible. These multiscale computational studies provide new insights at the atomic and molecular level as to how VP40-PM interactions are altered through single amino acid mutations. Given the high case fatality rates associated with Ebola virus disease in humans, it is essential to explore the mechanisms of viral assembly in the presence of mutations to mitigate the severity of the disease and understand the potential of future outbreaks.
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Affiliation(s)
- Michael D Cioffi
- Department of Physics, Florida International University, Miami, Florida 33199, United States
| | - Tej Sharma
- Department of Physics, Florida International University, Miami, Florida 33199, United States
| | - Balindile B Motsa
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States
| | - Nisha Bhattarai
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Bernard S Gerstman
- Department of Physics, Florida International University, Miami, Florida 33199, United States
- Biomolecular Sciences Institute, Florida International University, Miami, Florida 33199, United States
| | - Robert V Stahelin
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, United States
- The Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, Indiana 47907, United States
| | - Prem P Chapagain
- Department of Physics, Florida International University, Miami, Florida 33199, United States
- Biomolecular Sciences Institute, Florida International University, Miami, Florida 33199, United States
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Furuyama W, Yamada K, Sakaguchi M, Marzi A, Nanbo A. Marburg virus exploits the Rab11-mediated endocytic pathway in viral-particle production. Microbiol Spectr 2024; 12:e0026924. [PMID: 39078193 PMCID: PMC11370620 DOI: 10.1128/spectrum.00269-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 06/10/2024] [Indexed: 07/31/2024] Open
Abstract
Filoviruses produce viral particles with characteristic filamentous morphology. The major viral matrix protein, VP40, is trafficked to the plasma membrane and promotes viral particle formation and subsequent viral egress. In the present study, we assessed the role of the small GTPase Rab11-mediated endocytic pathway in Marburg virus (MARV) particle formation and budding. Although Rab11 was predominantly localized in the perinuclear region, it exhibited a more diffuse distribution in the cytoplasm of cells transiently expressing MARV VP40. Rab11 was incorporated into MARV-like particles. Expression of the dominant-negative form of Rab11 and knockdown of Rab11 decreased the amount of VP40 fractions in the cell periphery. Moreover, downregulation of Rab11 moderately reduced the release of MARV-like particles and authentic MARV. We further demonstrated that VP40 induces the distribution of the microtubule network toward the cell periphery, which was partly associated with Rab11. Depolymerization of microtubules reduced the accumulation of VP40 in the cell periphery along with viral particle formation. VP40 physically interacted with α-tubulin, a major component of microtubules, but not with Rab11. Taken together, these results suggested that VP40 partly interacts with microtubules and facilitates their distribution toward the cell periphery, leading to the trafficking of transiently tethering Rab11-positive vesicles toward the cell surface. As we previously demonstrated the role of Rab11 in the formation of Ebola virus particles, the results here suggest that filoviruses in general exploit the vesicle-trafficking machinery for proper virus-particle formation and subsequent egress. These pathways may be a potential target for the development of pan-filovirus therapeutics.IMPORTANCEFiloviruses, including Marburg and Ebola viruses, produce distinct filamentous viral particles. Although it is well known that the major viral matrix protein of these viruses, VP40, is trafficked to the cell surface and promotes viral particle production, details regarding the associated molecular mechanisms remain unclear. To address this knowledge gap, we investigated the role of the small GTPase Rab11-mediated endocytic pathway in this process. Our findings revealed that Marburg virus exploits the Rab11-mediated vesicle-trafficking pathway for the release of virus-like particles and authentic virions in a microtubule network-dependent manner. Previous findings demonstrated that Rab11 is also involved in Ebola virus-particle production. Taken together, these data suggest that filoviruses, in general, may hijack the microtubule-dependent vesicle-trafficking machinery for productive replication. Therefore, this pathway presents as a potential target for the development of pan-filovirus therapeutics.
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Affiliation(s)
- Wakako Furuyama
- National Research Center for the Control and Prevention of Infectious Diseases, Nagasaki University, Nagasaki, Japan
| | - Kento Yamada
- National Research Center for the Control and Prevention of Infectious Diseases, Nagasaki University, Nagasaki, Japan
| | - Miako Sakaguchi
- Central Laboratory, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan
| | - Andrea Marzi
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Asuka Nanbo
- National Research Center for the Control and Prevention of Infectious Diseases, Nagasaki University, Nagasaki, Japan
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3
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Sibert BS, Kim JY, Yang JE, Ke Z, Stobart CC, Moore ML, Wright ER. Assembly of respiratory syncytial virus matrix protein lattice and its coordination with fusion glycoprotein trimers. Nat Commun 2024; 15:5923. [PMID: 39004634 PMCID: PMC11247094 DOI: 10.1038/s41467-024-50162-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 06/28/2024] [Indexed: 07/16/2024] Open
Abstract
Respiratory syncytial virus (RSV) is an enveloped, filamentous, negative-strand RNA virus that causes significant respiratory illness worldwide. RSV vaccines are available, however there is still significant need for research to support the development of vaccines and therapeutics against RSV and related Mononegavirales viruses. Individual virions vary in size, with an average diameter of ~130 nm and ranging from ~500 nm to over 10 µm in length. Though the general arrangement of structural proteins in virions is known, we use cryo-electron tomography and sub-tomogram averaging to determine the molecular organization of RSV structural proteins. We show that the peripheral membrane-associated RSV matrix (M) protein is arranged in a packed helical-like lattice of M-dimers. We report that RSV F glycoprotein is frequently observed as pairs of trimers oriented in an anti-parallel conformation to support potential interactions between trimers. Our sub-tomogram averages indicate the positioning of F-trimer pairs is correlated with the underlying M lattice. These results provide insight into RSV virion organization and may aid in the development of RSV vaccines and anti-viral targets.
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Affiliation(s)
- Bryan S Sibert
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- Cryo-Electron Microscopy Research Center, Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- Midwest Center for Cryo-Electron Tomography, Department of Biochemistry, University of Wisconsin, Madison, WI, USA
| | - Joseph Y Kim
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- Department of Chemistry, University of Wisconsin, Madison, WI, USA
| | - Jie E Yang
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- Cryo-Electron Microscopy Research Center, Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- Midwest Center for Cryo-Electron Tomography, Department of Biochemistry, University of Wisconsin, Madison, WI, USA
| | - Zunlong Ke
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, USA
| | | | | | - Elizabeth R Wright
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA.
- Cryo-Electron Microscopy Research Center, Department of Biochemistry, University of Wisconsin, Madison, WI, USA.
- Midwest Center for Cryo-Electron Tomography, Department of Biochemistry, University of Wisconsin, Madison, WI, USA.
- Morgridge Institute for Research, Madison, WI, USA.
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Fletcher P, Clancy CS, O’Donnell KL, Doratt BM, Malherbe DC, Rhoderick JF, Feldmann F, Hanley PW, Takada A, Messaoudi I, Marzi A. Pathogenic differences of cynomolgus macaques after Taï Forest virus infection depend on the viral stock propagation. PLoS Pathog 2024; 20:e1012290. [PMID: 38861571 PMCID: PMC11195944 DOI: 10.1371/journal.ppat.1012290] [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: 01/29/2024] [Revised: 06/24/2024] [Accepted: 05/24/2024] [Indexed: 06/13/2024] Open
Abstract
Taï Forest virus (TAFV) is a negative-sense RNA virus in the Filoviridae family. TAFV has caused only a single human infection, but several disease outbreaks in chimpanzees have been linked to this virus. Limited research has been done on this human-pathogenic virus. We sought to establish an animal model to assess TAFV disease progression and pathogenicity at our facility. We had access to two different viral stock preparations from different institutions, both originating from the single human case. Type I interferon receptor knockout mice were inoculated with TAFV stock 1 or stock 2 by the intraperitoneal route. Inoculation resulted in 100% survival with no disease regardless of viral stock preparation or infectious dose. Next, cynomolgus macaques were inoculated with TAFV stock 1 or stock 2. Inoculation with TAFV stock 1 resulted in 100% survival and robust TAFV glycoprotein-specific IgG responses including neutralizing antibodies. In contrast, macaques infected with TAFV stock 2 developed disease and were euthanized 8-11 days after infection exhibiting viremia, thrombocytopenia, and increased inflammatory mediators identified by transcriptional analysis. Histopathologic analysis of tissue samples collected at necropsy confirmed classic filovirus disease in numerous organs. Genomic differences in both stock preparations were mapped to several viral genes which may have contributed to disease severity. Taken together, we demonstrate that infection with the two TAFV stocks resulted in no disease in mice and opposing disease phenotypes in cynomolgus macaques, highlighting the impact of viral stock propagation on pathogenicity in animal models.
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Affiliation(s)
- Paige Fletcher
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Chad S. Clancy
- Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Kyle L. O’Donnell
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Brianna M. Doratt
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, Kentucky, United States of America
| | - Delphine C. Malherbe
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, Kentucky, United States of America
| | - Joseph F. Rhoderick
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Friederike Feldmann
- Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Patrick W. Hanley
- Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Ayato Takada
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan
- International Collaboration Unit, International Institute for Zoonosis Control, Hokkaido University, Sapporo, Japan
- One Health Research Center, Hokkaido University, Sapporo, Japan
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Ilhem Messaoudi
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, Kentucky, United States of America
| | - Andrea Marzi
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
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5
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Motsa BB, Sharma T, Cioffi MD, Chapagain PP, Stahelin RV. Minor electrostatic changes robustly increase VP40 membrane binding, assembly, and budding of Ebola virus matrix protein derived virus-like particles. J Biol Chem 2024; 300:107213. [PMID: 38522519 PMCID: PMC11061732 DOI: 10.1016/j.jbc.2024.107213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/05/2024] [Accepted: 03/15/2024] [Indexed: 03/26/2024] Open
Abstract
Ebola virus (EBOV) is a filamentous negative-sense RNA virus, which causes severe hemorrhagic fever. There are limited vaccines or therapeutics for prevention and treatment of EBOV, so it is important to get a detailed understanding of the virus lifecycle to illuminate new drug targets. EBOV encodes for the matrix protein, VP40, which regulates assembly and budding of new virions from the inner leaflet of the host cell plasma membrane (PM). In this work, we determine the effects of VP40 mutations altering electrostatics on PM interactions and subsequent budding. VP40 mutations that modify surface electrostatics affect viral assembly and budding by altering VP40 membrane-binding capabilities. Mutations that increase VP40 net positive charge by one (e.g., Gly to Arg or Asp to Ala) increase VP40 affinity for phosphatidylserine and phosphatidylinositol 4,5-bisphosphate in the host cell PM. This increased affinity enhances PM association and budding efficiency leading to more effective formation of virus-like particles. In contrast, mutations that decrease net positive charge by one (e.g., Gly to Asp) lead to a decrease in assembly and budding because of decreased interactions with the anionic PM. Taken together, our results highlight the sensitivity of slight electrostatic changes on the VP40 surface for assembly and budding. Understanding the effects of single amino acid substitutions on viral budding and assembly will be useful for explaining changes in the infectivity and virulence of different EBOV strains, VP40 variants that occur in nature, and for long-term drug discovery endeavors aimed at EBOV assembly and budding.
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Affiliation(s)
- Balindile B Motsa
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana, USA
| | - Tej Sharma
- Department of Physics, Florida International University, Miami, Florida, USA
| | - Michael D Cioffi
- Department of Physics, Florida International University, Miami, Florida, USA
| | - Prem P Chapagain
- Department of Physics, Florida International University, Miami, Florida, USA; Biomolecular Sciences Institute, Florida International University, Miami, Florida, USA
| | - Robert V Stahelin
- Borch Department of Medicinal Chemistry and Molecular Pharmacology, Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, Indiana, USA.
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6
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Cioffi MD, Husby ML, Gerstman BS, Stahelin RV, Chapagain PP. Role of phosphatidic acid lipids on plasma membrane association of the Ebola virus matrix protein VP40. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159464. [PMID: 38360201 DOI: 10.1016/j.bbalip.2024.159464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 01/14/2024] [Accepted: 01/31/2024] [Indexed: 02/17/2024]
Abstract
The Ebola virus matrix protein VP40 is responsible for the formation of the viral matrix by localizing at the inner leaflet of the human plasma membrane (PM). Various lipid types, including PI(4,5)P2 (i.e. PIP2) and phosphatidylserine (PS), play active roles in this process. Specifically, the negatively charged headgroups of both PIP2 and PS interact with the basic residues of VP40 and stabilize it at the membrane surface, allowing for eventual egress. Phosphatidic acid (PA), resulting from the enzyme phospholipase D (PLD), is also known to play an active role in viral development. In this work, we performed a biophysical and computational analysis to investigate the effects of the presence of PA on the membrane localization and association of VP40. We used coarse-grained molecular dynamics simulations to quantify VP40 hexamer interactions with the inner leaflet of the PM. Analysis of the local distribution of lipids shows enhanced lipid clustering when PA is abundant in the membrane. We observed that PA lipids have a similar role to that of PS lipids in VP40 association due to the geometry and charge. Complementary experiments performed in cell culture demonstrate competition between VP40 and a canonical PA-binding protein for the PM. Also, inhibition of PA synthesis reduced the detectable budding of virus-like particles. These computational and experimental results provide new insights into the early stages of Ebola virus budding and the role that PA lipids have on the VP40-PM association.
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Affiliation(s)
- Michael D Cioffi
- Department of Physics, Florida International University, Miami, FL 33199, USA
| | - Monica L Husby
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
| | - Bernard S Gerstman
- Department of Physics, Florida International University, Miami, FL 33199, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Robert V Stahelin
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA; The Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA.
| | - Prem P Chapagain
- Department of Physics, Florida International University, Miami, FL 33199, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA.
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Kumar S, Dubey R, Mishra R, Gupta S, Dwivedi VD, Ray S, Jha NK, Verma D, Tsai LW, Dubey NK. Repurposing of SARS-CoV-2 compounds against Marburg Virus using MD simulation, mm/GBSA, PCA analysis, and free energy landscape. J Biomol Struct Dyn 2024:1-20. [PMID: 38450706 DOI: 10.1080/07391102.2024.2323701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 01/22/2024] [Indexed: 03/08/2024]
Abstract
The significant mortality rate associated with Marburg virus infection made it the greatest hazard among infectious diseases. Drug repurposing using in silico methods has been crucial in identifying potential compounds that could prevent viral replication by targeting the virus's primary proteins. This study aimed at repurposing the drugs of SARS-CoV-2 for identifying potential candidates against the matrix protein VP40 of the Marburg virus. Virtual screening was performed where the control compound, Nilotinib, showed a binding score of -9.99 kcal/mol. Based on binding scores, hit compounds 9549298, 11960895, 44545852, 51039094, and 89670174 were selected that had a lower binding score than the control. Subsequent molecular dynamics (MD) simulation revealed that compound 9549298 consistently formed a hydrogen bond with the residue Gln290. This was observed both in molecular docking and MD simulation poses, indicating a strong and significant interaction with the protein. 11960895 had the most stable and consistent RMSD pattern exhibited in 100 ns simulation, while 9549298 had the most identical RMSD plot compared to the control molecule. MM/PBSA analysis showed that the binding free energy (ΔG) of 9549298 and 11960895 was lower than the control, with -30.84 and -38.86 kcal/mol, respectively. It was observed by the PCA (principal component analysis) and FEL (free energy landscape) analysis that compounds 9549298 and 11960895 had lesser conformational variation. Overall, this study proposed 9549298 and 11960895 as potential binders of VP40 MARV that can cause its inhibition, however it inherently lacks experimental validation. Furthermore, the study proposes in-vitro experiments as the next step to validate these computational findings, offering a practical approach to further explore these compounds' potential as antiviral agents.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Sanjay Kumar
- Biological and Bio-computational Lab, Department of Life Science, School of Basic Science and Research, Sharda University, Greater Noida, UP, India
| | - Rajni Dubey
- Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei City, Taiwan
| | - Richa Mishra
- Department of Computer Engineering, Parul University, Vadodara, Gujarat, India
| | - Saurabh Gupta
- Department of Biotechnology, GLA University, Mathura, Uttar Pradesh, India
| | - Vivek Dhar Dwivedi
- Center for Global Health Research, Saveetha Medical College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India
- Bioinformatics Research Division, Greater Noida, UP, India
| | - Subhasree Ray
- Department of Life Science, School of Basic Science and Research, Sharda University, Greater Noida, India
| | - Niraj Kumar Jha
- School of Bioengineering & Biosciences, Lovely Professional University, Phagwara, India
- Centre of Research Impact and Outreach, Chitkara University Institute of Engineering and Technology, Chitkara University, Punjab, India
| | - Devvret Verma
- Department of Biotechnology, Graphic Era (Deemed to Be University), Dehradun, Uttarakhand, India
| | - Lung-Wen Tsai
- Department of Medicine Research, Taipei Medical University Hospital, Taipei, Taiwan
- Department of Information Technology Office, Taipei Medical University Hospital, Taipei, Taiwan
- Graduate Institute of Data Science, College of Management, Taipei Medical University, Taipei, Taiwan
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8
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Johnson KA, Budicini MR, Bhattarai N, Sharma T, Urata S, Gerstman BS, Chapagain PP, Li S, Stahelin RV. PI(4,5)P 2 binding sites in the Ebola virus matrix protein VP40 modulate assembly and budding. J Lipid Res 2024; 65:100512. [PMID: 38295986 PMCID: PMC10909612 DOI: 10.1016/j.jlr.2024.100512] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 01/12/2024] [Accepted: 01/17/2024] [Indexed: 03/02/2024] Open
Abstract
Ebola virus (EBOV) causes severe hemorrhagic fever in humans and is lethal in a large percentage of those infected. The EBOV matrix protein viral protein 40 kDa (VP40) is a peripheral binding protein that forms a shell beneath the lipid bilayer in virions and virus-like particles (VLPs). VP40 is required for virus assembly and budding from the host cell plasma membrane. VP40 is a dimer that can rearrange into oligomers at the plasma membrane interface, but it is unclear how these structures form and how they are stabilized. We therefore investigated the ability of VP40 to form stable oligomers using in vitro and cellular assays. We characterized two lysine-rich regions in the VP40 C-terminal domain (CTD) that bind phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) and play distinct roles in lipid binding and the assembly of the EBOV matrix layer. The extensive analysis of VP40 with and without lipids by hydrogen deuterium exchange mass spectrometry revealed that VP40 oligomers become extremely stable when VP40 binds PI(4,5)P2. The PI(4,5)P2-induced stability of VP40 dimers and oligomers is a critical factor in VP40 oligomerization and release of VLPs from the plasma membrane. The two lysine-rich regions of the VP40 CTD have different roles with respect to interactions with plasma membrane phosphatidylserine (PS) and PI(4,5)P2. CTD region 1 (Lys221, Lys224, and Lys225) interacts with PI(4,5)P2 more favorably than PS and is important for VP40 extent of oligomerization. In contrast, region 2 (Lys270, Lys274, Lys275, and Lys279) mediates VP40 oligomer stability via lipid interactions and has a more prominent role in release of VLPs.
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Affiliation(s)
- Kristen A Johnson
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Melissa R Budicini
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Nisha Bhattarai
- Department of Physics, Florida International University, Miami, FL, USA
| | - Tej Sharma
- Department of Physics, Florida International University, Miami, FL, USA
| | - Sarah Urata
- Department of Medicine, University of California San Diego, San Diego, CA, USA
| | - Bernard S Gerstman
- Department of Physics, Florida International University, Miami, FL, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL, USA
| | - Prem P Chapagain
- Department of Physics, Florida International University, Miami, FL, USA; Biomolecular Sciences Institute, Florida International University, Miami, FL, USA
| | - Sheng Li
- Biomolecular Sciences Institute, Florida International University, Miami, FL, USA
| | - Robert V Stahelin
- Department of Medicinal Chemistry and Molecular Pharmacology and the Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN, USA.
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9
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Motsa BB, Sharma T, Chapagain PP, Stahelin RV. Minor changes in electrostatics robustly increase VP40 membrane binding, assembly, and budding of Ebola virus matrix protein derived virus-like particles. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.30.578092. [PMID: 38352396 PMCID: PMC10862912 DOI: 10.1101/2024.01.30.578092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Ebola virus (EBOV) is a filamentous negative-sense RNA virus which causes severe hemorrhagic fever. There are limited vaccines or therapeutics for prevention and treatment of EBOV, so it is important to get a detailed understanding of the virus lifecycle to illuminate new drug targets. EBOV encodes for the matrix protein, VP40, which regulates assembly and budding of new virions from the inner leaflet of the host cell plasma membrane (PM). In this work we determine the effects of VP40 mutations altering electrostatics on PM interactions and subsequent budding. VP40 mutations that modify surface electrostatics affect viral assembly and budding by altering VP40 membrane binding capabilities. Mutations that increase VP40 net positive charge by one (e.g., Gly to Arg or Asp to Ala) increase VP40 affinity for phosphatidylserine (PS) and PI(4,5)P2 in the host cell PM. This increased affinity enhances PM association and budding efficiency leading to more effective formation of virus-like particles (VLPs). In contrast, mutations that decrease net positive charge by one (e.g., Gly to Asp) lead to a decrease in assembly and budding because of decreased interactions with the anionic PM. Taken together our results highlight the sensitivity of slight electrostatic changes on the VP40 surface for assembly and budding. Understanding the effects of single amino acid substitutions on viral budding and assembly will be useful for explaining changes in the infectivity and virulence of different EBOV strains, VP40 variants that occur in nature, and for long-term drug discovery endeavors aimed at EBOV assembly and budding.
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Affiliation(s)
- Balindile B. Motsa
- Borch Department of Medicinal Chemistry and Molecular Pharmacology and the Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
| | - Tej Sharma
- Department of Physics, Florida International University, Miami, FL 33199, USA
| | - Prem P. Chapagain
- Department of Physics, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Robert V. Stahelin
- Borch Department of Medicinal Chemistry and Molecular Pharmacology and the Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
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10
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Bodmer BS, Breithaupt A, Heung M, Brunetti JE, Henkel C, Müller-Guhl J, Rodríguez E, Wendt L, Winter SL, Vallbracht M, Müller A, Römer S, Chlanda P, Muñoz-Fontela C, Hoenen T, Escudero-Pérez B. In vivo characterization of the novel ebolavirus Bombali virus suggests a low pathogenic potential for humans. Emerg Microbes Infect 2023; 12:2164216. [PMID: 36580440 PMCID: PMC9858441 DOI: 10.1080/22221751.2022.2164216] [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] [Indexed: 12/30/2022]
Abstract
Ebolaviruses cause outbreaks of haemorrhagic fever in Central and West Africa. Some members of this genus such as Ebola virus (EBOV) are highly pathogenic, with case fatality rates of up to 90%, whereas others such as Reston virus (RESTV) are apathogenic for humans. Bombali virus (BOMV) is a novel ebolavirus for which complete genome sequences were recently found in free-tailed bats, although no infectious virus could be isolated. Its pathogenic potential for humans is unknown. To address this question, we first determined whether proteins encoded by the available BOMV sequence found in Chaerephon pumilus were functional in in vitro assays. The correction of an apparent sequencing error in the glycoprotein based on these data then allowed us to generate infectious BOMV using reverse genetics and characterize its infection of human cells. Furthermore, we used HLA-A2-transgenic, NOD-scid-IL-2γ receptor-knockout (NSG-A2) mice reconstituted with human haematopoiesis as a model to evaluate the pathogenicity of BOMV in vivo in a human-like immune environment. These data demonstrate that not only does BOMV show a slower growth rate than EBOV in vitro, but it also shows low pathogenicity in humanized mice, comparable to previous studies using RESTV. Taken together, these findings suggest a low pathogenic potential of BOMV for humans.
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Affiliation(s)
- B. S. Bodmer
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - A. Breithaupt
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - M. Heung
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - J. E. Brunetti
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - C. Henkel
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - J. Müller-Guhl
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Leibniz Institute of Virology, Hamburg, Germany
| | - E. Rodríguez
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,German Center for Infection Research (DZIF), Partner Site Hamburg-Luebeck-Borstel, Braunschweig, Germany
| | - L. Wendt
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - S. L. Winter
- Schaller Research Groups, Department of Infectious Diseases, Virology, Heidelberg University Hospital, Heidelberg, Germany
| | - M. Vallbracht
- Schaller Research Groups, Department of Infectious Diseases, Virology, Heidelberg University Hospital, Heidelberg, Germany
| | - A. Müller
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - S. Römer
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - P. Chlanda
- Schaller Research Groups, Department of Infectious Diseases, Virology, Heidelberg University Hospital, Heidelberg, Germany
| | - C. Muñoz-Fontela
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,German Center for Infection Research (DZIF), Partner Site Hamburg-Luebeck-Borstel, Braunschweig, Germany
| | - T. Hoenen
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany, T. Hoenen Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Südufer 10, Greifswald – Insel Riems, 17493Germany
| | - B. Escudero-Pérez
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,German Center for Infection Research (DZIF), Partner Site Hamburg-Luebeck-Borstel, Braunschweig, Germany
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11
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Werner AD, Schauflinger M, Norris MJ, Klüver M, Trodler A, Herwig A, Brandstädter C, Dillenberger M, Klebe G, Heine A, Saphire EO, Becker K, Becker S. The C-terminus of Sudan ebolavirus VP40 contains a functionally important CX nC motif, a target for redox modifications. Structure 2023; 31:1038-1051.e7. [PMID: 37392738 DOI: 10.1016/j.str.2023.06.004] [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: 02/16/2023] [Revised: 05/10/2023] [Accepted: 06/06/2023] [Indexed: 07/03/2023]
Abstract
The Ebola virus matrix protein VP40 mediates viral budding and negatively regulates viral RNA synthesis. The mechanisms by which these two functions are exerted and regulated are unknown. Using a high-resolution crystal structure of Sudan ebolavirus (SUDV) VP40, we show here that two cysteines in the flexible C-terminal arm of VP40 form a stabilizing disulfide bridge. Notably, the two cysteines are targets of posttranslational redox modifications and interact directly with the host`s thioredoxin system. Mutation of the cysteines impaired the budding function of VP40 and relaxed its inhibitory role for viral RNA synthesis. In line with these results, the growth of recombinant Ebola viruses carrying cysteine mutations was impaired and the released viral particles were elongated. Our results revealed the exact positions of the cysteines in the C-terminal arm of SUDV VP40. The cysteines and/or their redox status are critically involved in the differential regulation of viral budding and viral RNA synthesis.
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Affiliation(s)
| | | | - Michael J Norris
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Michael Klüver
- Institute for Virology, Philipps-University of Marburg, Marburg, Germany
| | - Anna Trodler
- Institute for Virology, Philipps-University of Marburg, Marburg, Germany
| | - Astrid Herwig
- Institute for Virology, Philipps-University of Marburg, Marburg, Germany
| | - Christina Brandstädter
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Melissa Dillenberger
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Gerhard Klebe
- Institute for Pharmaceutical Chemistry, Philipps-University of Marburg, Marburg, Germany
| | - Andreas Heine
- Institute for Pharmaceutical Chemistry, Philipps-University of Marburg, Marburg, Germany
| | | | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Giessen, Germany
| | - Stephan Becker
- Institute for Virology, Philipps-University of Marburg, Marburg, Germany.
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12
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Fletcher P, O'Donnell KL, Doratt BM, Malherbe DC, Clancy CS, Rhoderick JF, Feldmann F, Hanley PW, Ksiazek TG, Geisbert TW, Messaoudi I, Marzi A. Single-dose VSV-based vaccine protects cynomolgus macaques from disease after Taï Forest virus infection. Emerg Microbes Infect 2023:2239950. [PMID: 37470396 PMCID: PMC10392270 DOI: 10.1080/22221751.2023.2239950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
Taï Forest virus (TAFV) is a lesser-known ebolavirus that causes lethal infections in chimpanzees and is responsible for a single human case. Limited research has been done on this human pathogen; however, with the recent emergence of filoviruses in West Africa, further investigation and countermeasure development against this virus is warranted.We developed a vesicular stomatitis virus (VSV)-based vaccine expressing the TAFV glycoprotein as the viral antigen and assessed it for protective efficacy in nonhuman primates (NHPs). Following a single high-dose vaccination, NHPs developed antigen-specific binding and neutralizing antibodies as well as modest T cell responses. Importantly, all vaccinated NHPs were uniformly protected from disease after lethal TAFV challenge while the naïve control group succumbed to the disease. Histopathologic lesions consistent with filovirus disease were present in control NHPs but were not observed in vaccinated NHPs. Transcriptional analysis of whole blood samples obtained after vaccination and challenge was performed to gain insight into molecular underpinnings conferring protection. Differentially expressed genes (DEG) detected 7 days post-vaccination were enriched to processes associated with innate immunity and antiviral responses. Only a small number of DEG was detected in vaccinated NHPs post-challenge while over 1,000 DEG were detected in control NHPs at end-stage disease which mapped to gene ontology terms indicative of defense responses and inflammation. Taken together, this data demonstrates the effective single-dose protection of the VSV-TAFV vaccine, and its potential for use in outbreaks.
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Affiliation(s)
- Paige Fletcher
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Kyle L O'Donnell
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Brianna M Doratt
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Delphine C Malherbe
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Chad S Clancy
- Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Joseph F Rhoderick
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Friederike Feldmann
- Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Patrick W Hanley
- Rocky Mountain Veterinary Branch, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
| | - Thomas G Ksiazek
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Thomas W Geisbert
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Ilhem Messaoudi
- Department of Microbiology, Immunology, and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Andrea Marzi
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA
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13
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Wang S, Liang B, Wang W, Li L, Feng N, Zhao Y, Wang T, Yan F, Yang S, Xia X. Viral vectored vaccines: design, development, preventive and therapeutic applications in human diseases. Signal Transduct Target Ther 2023; 8:149. [PMID: 37029123 PMCID: PMC10081433 DOI: 10.1038/s41392-023-01408-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 03/06/2023] [Accepted: 03/14/2023] [Indexed: 04/09/2023] Open
Abstract
Human diseases, particularly infectious diseases and cancers, pose unprecedented challenges to public health security and the global economy. The development and distribution of novel prophylactic and therapeutic vaccines are the prioritized countermeasures of human disease. Among all vaccine platforms, viral vector vaccines offer distinguished advantages and represent prominent choices for pathogens that have hampered control efforts based on conventional vaccine approaches. Currently, viral vector vaccines remain one of the best strategies for induction of robust humoral and cellular immunity against human diseases. Numerous viruses of different families and origins, including vesicular stomatitis virus, rabies virus, parainfluenza virus, measles virus, Newcastle disease virus, influenza virus, adenovirus and poxvirus, are deemed to be prominent viral vectors that differ in structural characteristics, design strategy, antigen presentation capability, immunogenicity and protective efficacy. This review summarized the overall profile of the design strategies, progress in advance and steps taken to address barriers to the deployment of these viral vector vaccines, simultaneously highlighting their potential for mucosal delivery, therapeutic application in cancer as well as other key aspects concerning the rational application of these viral vector vaccines. Appropriate and accurate technological advances in viral vector vaccines would consolidate their position as a leading approach to accelerate breakthroughs in novel vaccines and facilitate a rapid response to public health emergencies.
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Affiliation(s)
- Shen Wang
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Bo Liang
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Weiqi Wang
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
- College of Veterinary Medicine, Jilin University, Changchun, China
| | - Ling Li
- China National Research Center for Exotic Animal Diseases, China Animal Health and Epidemiology Center, Qingdao, China
| | - Na Feng
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Yongkun Zhao
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Tiecheng Wang
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Feihu Yan
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China.
| | - Songtao Yang
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China.
| | - Xianzhu Xia
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China.
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14
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Loshkareva AS, Popova MM, Shilova LA, Fedorova NV, Timofeeva TA, Galimzyanov TR, Kuzmin PI, Knyazev DG, Batishchev OV. Influenza A Virus M1 Protein Non-Specifically Deforms Charged Lipid Membranes and Specifically Interacts with the Raft Boundary. MEMBRANES 2023; 13:76. [PMID: 36676883 PMCID: PMC9864314 DOI: 10.3390/membranes13010076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/26/2022] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Topological rearrangements of biological membranes, such as fusion and fission, often require a sophisticated interplay between different proteins and cellular membranes. However, in the case of fusion proteins of enveloped viruses, even one molecule can execute membrane restructurings. Growing evidence indicates that matrix proteins of enveloped viruses can solely trigger the membrane bending required for another crucial step in virogenesis, the budding of progeny virions. For the case of the influenza A virus matrix protein M1, different studies report both in favor and against M1 being able to produce virus-like particles without other viral proteins. Here, we investigated the physicochemical mechanisms of M1 membrane activity on giant unilamellar vesicles of different lipid compositions using fluorescent confocal microscopy. We confirmed that M1 predominantly interacts electrostatically with the membrane, and its ability to deform the lipid bilayer is non-specific and typical for membrane-binding proteins and polypeptides. However, in the case of phase-separating membranes, M1 demonstrates a unique ability to induce macro-phase separation, probably due to the high affinity of M1's amphipathic helices to the raft boundary. Thus, we suggest that M1 is tailored to deform charged membranes with a specific activity in the case of phase-separating membranes.
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Affiliation(s)
- Anna S. Loshkareva
- Laboratory of Bioelectrochemistry, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia
| | - Marina M. Popova
- Laboratory of Bioelectrochemistry, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia
| | - Liudmila A. Shilova
- Laboratory of Bioelectrochemistry, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia
| | - Natalia V. Fedorova
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Tatiana A. Timofeeva
- Laboratory of Physiology of Viruses, D. I. Ivanovsky Institute of Virology, FSBI N. F. Gamaleya NRCEM, Ministry of Health of Russian Federation, 123098 Moscow, Russia
| | - Timur R. Galimzyanov
- Laboratory of Bioelectrochemistry, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia
| | - Petr I. Kuzmin
- Laboratory of Bioelectrochemistry, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia
| | - Denis G. Knyazev
- Institute of Biophysics, Johannes Kepler University Linz, 4020 Linz, Austria
| | - Oleg V. Batishchev
- Laboratory of Bioelectrochemistry, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia
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15
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Husby ML, Amiar S, Prugar LI, David EA, Plescia CB, Huie KE, Brannan JM, Dye JM, Pienaar E, Stahelin RV. Phosphatidylserine clustering by the Ebola virus matrix protein is a critical step in viral budding. EMBO Rep 2022; 23:e51709. [PMID: 36094794 PMCID: PMC9638875 DOI: 10.15252/embr.202051709] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 08/16/2022] [Accepted: 08/19/2022] [Indexed: 07/28/2023] Open
Abstract
Phosphatidylserine (PS) is a critical lipid factor in the assembly and spread of numerous lipid-enveloped viruses. Here, we describe the ability of the Ebola virus (EBOV) matrix protein eVP40 to induce clustering of PS and promote viral budding in vitro, as well as the ability of an FDA-approved drug, fendiline, to reduce PS clustering and subsequent virus budding and entry. To gain mechanistic insight into fendiline inhibition of EBOV replication, multiple in vitro assays were run including imaging, viral budding and viral entry assays. Fendiline lowers PS content in mammalian cells and PS in the plasma membrane, where the ability of VP40 to form new virus particles is greatly lower. Further, particles that form from fendiline-treated cells have altered particle morphology and cannot significantly infect/enter cells. These complementary studies reveal the mechanism by which EBOV matrix protein clusters PS to enhance viral assembly, budding, and spread from the host cell while also laying the groundwork for fundamental drug targeting strategies.
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Affiliation(s)
- Monica L Husby
- Department of Medicinal Chemistry & Molecular PharmacologyPurdue UniversityWest LafayetteINUSA
- Purdue Institute of Inflammation, Immunology and Infectious Disease (PI4D)Purdue University, West LafayetteWest LafayetteINUSA
| | - Souad Amiar
- Department of Medicinal Chemistry & Molecular PharmacologyPurdue UniversityWest LafayetteINUSA
- Purdue Institute of Inflammation, Immunology and Infectious Disease (PI4D)Purdue University, West LafayetteWest LafayetteINUSA
| | - Laura I Prugar
- United States Army Medical Research Institute of Infectious Diseases USAMRIIDFort DetrickFrederickMDUSA
| | - Emily A David
- Department of Medicinal Chemistry & Molecular PharmacologyPurdue UniversityWest LafayetteINUSA
| | - Caroline B Plescia
- Department of Medicinal Chemistry & Molecular PharmacologyPurdue UniversityWest LafayetteINUSA
| | - Kathleen E Huie
- United States Army Medical Research Institute of Infectious Diseases USAMRIIDFort DetrickFrederickMDUSA
| | - Jennifer M Brannan
- United States Army Medical Research Institute of Infectious Diseases USAMRIIDFort DetrickFrederickMDUSA
| | - John M Dye
- United States Army Medical Research Institute of Infectious Diseases USAMRIIDFort DetrickFrederickMDUSA
| | - Elsje Pienaar
- Purdue Institute of Inflammation, Immunology and Infectious Disease (PI4D)Purdue University, West LafayetteWest LafayetteINUSA
- Weldon School of Biomedical EngineeringPurdue UniversityWest LafayetteINUSA
| | - Robert V Stahelin
- Department of Medicinal Chemistry & Molecular PharmacologyPurdue UniversityWest LafayetteINUSA
- Purdue Institute of Inflammation, Immunology and Infectious Disease (PI4D)Purdue University, West LafayetteWest LafayetteINUSA
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16
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Liu CH, Hu YT, Wong SH, Lin LT. Therapeutic Strategies against Ebola Virus Infection. Viruses 2022; 14:v14030579. [PMID: 35336986 PMCID: PMC8954160 DOI: 10.3390/v14030579] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/03/2022] [Accepted: 03/08/2022] [Indexed: 12/10/2022] Open
Abstract
Since the 2014–2016 epidemic, Ebola virus (EBOV) has spread to several countries and has become a major threat to global health. EBOV is a risk group 4 pathogen, which imposes significant obstacles for the development of countermeasures against the virus. Efforts have been made to develop anti-EBOV immunization and therapeutics, with three vaccines and two antibody-based therapeutics approved in recent years. Nonetheless, the high fatality of Ebola virus disease highlights the need to continuously develop antiviral strategies for the future management of EBOV outbreaks in conjunction with vaccination programs. This review aims to highlight potential EBOV therapeutics and their target(s) of inhibition, serving as a summary of the literature to inform readers of the novel candidates available in the continued search for EBOV antivirals.
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Affiliation(s)
- Ching-Hsuan Liu
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan;
| | - Yee-Tung Hu
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan;
| | - Shu Hui Wong
- International Ph.D. Program in Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan;
| | - Liang-Tzung Lin
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan;
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan;
- Correspondence:
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17
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Bhattarai N, Pavadai E, Pokhrel R, Baral P, Hossen L, Stahelin RV, Chapagain PP, Gerstman BS. Ebola virus protein VP40 binding to Sec24c for transport to the plasma membrane. Proteins 2022; 90:340-350. [PMID: 34431571 PMCID: PMC8738135 DOI: 10.1002/prot.26221] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 07/01/2021] [Accepted: 08/16/2021] [Indexed: 02/03/2023]
Abstract
Outbreaks of the Ebola virus (EBOV) continue to occur and while a vaccine and treatment are now available, there remains a dearth of options for those who become sick with EBOV disease. An understanding at the atomic and molecular level of the various steps in the EBOV replication cycle can provide molecular targets for disrupting the virus. An important step in the EBOV replication cycle is the transport of EBOV structural matrix VP40 protein molecules to the plasma membrane inner leaflet, which involves VP40 binding to the host cell's Sec24c protein. Though some VP40 residues involved in the binding are known, the molecular details of VP40-Sec24c binding are not known. We use various molecular computational techniques to investigate the molecular details of how EBOV VP40 binds with the Sec24c complex of the ESCRT-I pathway. We employed different docking programs to identify the VP40-binding site on Sec24c and then performed molecular dynamics simulations to determine the atomic details and binding interactions of the complex. We also investigated how the inter-protein interactions of the complex are affected upon mutations of VP40 amino acids in the Sec24c-binding region. Our results provide a molecular basis for understanding previous coimmunoprecipitation experimental studies. In addition, we found that VP40 can bind to a site on Sec24c that can also bind Sec23 and suggests that VP40 may use the COPII transport mechanism in a manner that may not need the Sec23 protein in order for VP40 to be transported to the plasma membrane.
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Affiliation(s)
- Nisha Bhattarai
- Department of Physics, Florida International University, Miami, FL 33199, USA
| | - Elumalai Pavadai
- Department of Physics, Florida International University, Miami, FL 33199, USA
| | - Rudramani Pokhrel
- Department of Physics, Florida International University, Miami, FL 33199, USA
| | - Prabin Baral
- Department of Physics, Florida International University, Miami, FL 33199, USA
| | - Lokman Hossen
- Department of Physics, Florida International University, Miami, FL 33199, USA
| | - Robert V. Stahelin
- Department of Medicinal Chemistry & Molecular Pharmacology and the Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette IN 47906
| | - Prem P. Chapagain
- Department of Physics, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Bernard S. Gerstman
- Department of Physics, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
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18
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Identification of novel chemical compounds targeting filovirus VP40-mediated particle production. Antiviral Res 2022; 199:105267. [DOI: 10.1016/j.antiviral.2022.105267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 02/13/2022] [Accepted: 02/22/2022] [Indexed: 11/22/2022]
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19
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Batishchev OV. Physico-Chemical Mechanisms of the Functioning of Membrane-Active Proteins of Enveloped Viruses. BIOCHEMISTRY (MOSCOW) SUPPLEMENT. SERIES A, MEMBRANE AND CELL BIOLOGY 2022; 16:247-260. [PMCID: PMC9734521 DOI: 10.1134/s1990747822050038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/01/2022] [Accepted: 06/02/2022] [Indexed: 12/14/2022]
Abstract
Over the past few years, the attention of the whole world has been riveted to the emergence of new dangerous strains of viruses, among which a special place is occupied by coronaviruses that have overcome the interspecies barrier in the past 20 years: SARS viruses (SARS), Middle East respiratory syndrome (MERS), as well as a new coronavirus infection (SARS-CoV-2), which caused the largest pandemic since the Spanish flu in 1918. Coronaviruses are members of a class of enveloped viruses that have a lipoprotein envelope. This class also includes such serious pathogens as human immunodeficiency virus (HIV), hepatitis, Ebola virus, influenza, etc. Despite significant differences in the clinical picture of the course of disease caused by enveloped viruses, they themselves have a number of characteristic features, which determine their commonality. Regardless of the way of penetration into the cell—by endocytosis or direct fusion with the cell membrane—enveloped viruses are characterized by the following stages of interaction with the target cell: binding to receptors on the cell surface, interaction of the surface glycoproteins of the virus with the membrane structures of the infected cell, fusion of the lipid envelope of the virion with plasma or endosomal membrane, destruction of the protein capsid and its dissociation from the viral nucleoprotein. Subsequently, within the infected cell, the newly synthesized viral proteins must self-assemble on various membrane structures to form a progeny virion. Thus, both the initial stages of viral infection and the assembly and release of new viral particles are associated with the activity of viral proteins in relation to the cell membrane and its organelles. This review is devoted to the analysis of physicochemical mechanisms of functioning of the main structural proteins of a number of enveloped viruses in order to identify possible strategies for the membrane activity of such proteins at various stages of viral infection of the cell.
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Affiliation(s)
- O. V. Batishchev
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia
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20
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Gong M, Yang Y, Huang Y, Gan T, Wu Y, Gao H, Li Q, Nie J, Huang W, Wang Y, Zhang R, Zhong J, Deng F, Rao Y, Ding Q. Novel quinolone derivatives targeting human dihydroorotate dehydrogenase suppress Ebola virus infection in vitro. Antiviral Res 2021; 194:105161. [PMID: 34391783 DOI: 10.1016/j.antiviral.2021.105161] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 07/30/2021] [Accepted: 08/08/2021] [Indexed: 11/28/2022]
Abstract
Ebola virus (EBOV) has emerged as a significant public health concern since the 2013-2016 outbreak in West Africa. Currently, no effective antiviral treatments have been approved for clinical use. Compound 1 RYL-634 is a quinolone-derived compound that can inhibit dihydroorotate dehydrogenase, a rate-limiting enzyme in the de novo pyrimidine synthesis pathway and it exhibited antiviral activity against multiple RNA virus infection. In this study, we evaluated the efficacy of a panel of newly developed compounds based on RYL-634 against EBOV infection. Our data showed that RYL-634 as well as its derivatives are effective against EBOV transcription- and replication-competent virus-like particle (trVLP) infection and authentic EBOV infection in vitro at low nanomolar IC50 values and relatively high CC50. Of note, the new derivative RYL-687 had the lowest IC50 at approximately 7 nM and was almost 6 times more potent than remdesivir (GS-5734). Exogenous addition of different metabolites in the pyrimidine de novo synthesis pathway confirmed DHODH as the target of RYL-687. These data provide evidence that such quinolone-derived compounds are promising therapeutic candidates against EBOV infection.
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Affiliation(s)
- Mingli Gong
- School of Medicine, Tsinghua University, Beijing, 100084, China
| | - Yiqing Yang
- School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China
| | - Yi Huang
- Wuhan National Biosafety Laboratory, Chinese Academy of Science, Wuhan, 43007, China
| | - Tianyu Gan
- CAS Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yue Wu
- School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China
| | - Hongying Gao
- School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China
| | - Qianqian Li
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, 102629, China
| | - Jianhui Nie
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, 102629, China
| | - Weijin Huang
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, 102629, China
| | - Youchun Wang
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, 102629, China
| | - Rong Zhang
- MOE/NHC/CAMS Key Laboratory of Medical Molecular Virology, School of BasicMedical Sciences, Fudan University, Shanghai, 200032, China
| | - Jin Zhong
- CAS Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Fei Deng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China; Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Yu Rao
- School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing, 100084, China.
| | - Qiang Ding
- School of Medicine, Tsinghua University, Beijing, 100084, China.
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21
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Johnson KA, Bhattarai N, Budicini MR, LaBonia CM, Baker SCB, Gerstman BS, Chapagain PP, Stahelin RV. Cysteine Mutations in the Ebolavirus Matrix Protein VP40 Promote Phosphatidylserine Binding by Increasing the Flexibility of a Lipid-Binding Loop. Viruses 2021; 13:1375. [PMID: 34372582 PMCID: PMC8310056 DOI: 10.3390/v13071375] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 07/08/2021] [Accepted: 07/13/2021] [Indexed: 11/25/2022] Open
Abstract
Ebolavirus (EBOV) is a negative-sense RNA virus that causes severe hemorrhagic fever in humans. The matrix protein VP40 facilitates viral budding by binding to lipids in the host cell plasma membrane and driving the formation of filamentous, pleomorphic virus particles. The C-terminal domain of VP40 contains two highly-conserved cysteine residues at positions 311 and 314, but their role in the viral life cycle is unknown. We therefore investigated the properties of VP40 mutants in which the conserved cysteine residues were replaced with alanine. The C311A mutation significantly increased the affinity of VP40 for membranes containing phosphatidylserine (PS), resulting in the assembly of longer virus-like particles (VLPs) compared to wild-type VP40. The C314A mutation also increased the affinity of VP40 for membranes containing PS, albeit to a lesser degree than C311A. The double mutant behaved in a similar manner to the individual mutants. Computer modeling revealed that both cysteine residues restrain a loop segment containing lysine residues that interact with the plasma membrane, but Cys311 has the dominant role. Accordingly, the C311A mutation increases the flexibility of this membrane-binding loop, changes the profile of hydrogen bonding within VP40 and therefore binds to PS with greater affinity. This is the first evidence that mutations in VP40 can increase its affinity for biological membranes and modify the length of Ebola VLPs. The Cys311 and Cys314 residues therefore play an important role in dynamic interactions at the plasma membrane by modulating the ability of VP40 to bind PS.
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Affiliation(s)
- Kristen A. Johnson
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; (K.A.J.); (M.R.B.); (C.M.L.); (S.C.B.B.)
| | - Nisha Bhattarai
- Department of Physics, Florida International University, Miami, FL 33199, USA; (N.B.); (B.S.G.); (P.P.C.)
| | - Melissa R. Budicini
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; (K.A.J.); (M.R.B.); (C.M.L.); (S.C.B.B.)
| | - Carolyn M. LaBonia
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; (K.A.J.); (M.R.B.); (C.M.L.); (S.C.B.B.)
| | - Sarah Catherine B. Baker
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; (K.A.J.); (M.R.B.); (C.M.L.); (S.C.B.B.)
| | - Bernard S. Gerstman
- Department of Physics, Florida International University, Miami, FL 33199, USA; (N.B.); (B.S.G.); (P.P.C.)
- The Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Prem P. Chapagain
- Department of Physics, Florida International University, Miami, FL 33199, USA; (N.B.); (B.S.G.); (P.P.C.)
- The Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Robert V. Stahelin
- Department of Medicinal Chemistry and Molecular Pharmacology and the Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
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22
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P300-mediated NEDD4 acetylation drives ebolavirus VP40 egress by enhancing NEDD4 ligase activity. PLoS Pathog 2021; 17:e1009616. [PMID: 34111220 PMCID: PMC8191996 DOI: 10.1371/journal.ppat.1009616] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 05/06/2021] [Indexed: 02/07/2023] Open
Abstract
The final stage of Ebola virus (EBOV) replication is budding from host cells, where the matrix protein VP40 is essential for driving this process. Many post-translational modifications such as ubiquitination are involved in VP40 egress, but acetylation has not been studied yet. Here, we characterize NEDD4 is acetylated at a conserved Lys667 mediated by the acetyltransferase P300 which drives VP40 egress process. Importantly, P300-mediated NEDD4 acetylation promotes NEDD4-VP40 interaction which enhances NEDD4 E3 ligase activity and is essential for the activation of VP40 ubiquitination and subsequent egress. Finally, we find that Zaire ebolavirus production is dramatically reduced in P300 knockout cell lines, suggesting that P300-mediated NEDD4 acetylation may have a physiological effect on Ebola virus life cycle. Thus, our study identifies an acetylation-dependent regulatory mechanism that governs VP40 ubiquitination and provides insights into how acetylation controls EBOV VP40 egress. Ebola virus (EBOV) is one of the deadliest pathogens, causing fatal hemorrhagic fever diseases in humans and primates. In this study, we find that P300-mediated NEDD4 acetylation facilitates EBOV egress. Acetylation promotes NEDD4-VP40 interactions which enhances NEDD4 E3 ligase activity and is essential for the activation of VP40 ubiquitination and subsequent egress. This study implies that inhibitory effect of acetylation can be regarded as an attractive candidate of drug target for the treatment of Ebola virus disease.
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23
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Amiar S, Husby ML, Wijesinghe KJ, Angel S, Bhattarai N, Gerstman BS, Chapagain PP, Li S, Stahelin RV. Lipid-specific oligomerization of the Marburg virus matrix protein VP40 is regulated by two distinct interfaces for virion assembly. J Biol Chem 2021; 296:100796. [PMID: 34019871 PMCID: PMC8191294 DOI: 10.1016/j.jbc.2021.100796] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 05/12/2021] [Accepted: 05/14/2021] [Indexed: 02/03/2023] Open
Abstract
Marburg virus (MARV) is a lipid-enveloped virus harboring a negative-sense RNA genome, which has caused sporadic outbreaks of viral hemorrhagic fever in sub-Saharan Africa. MARV assembles and buds from the host cell plasma membrane where MARV matrix protein (mVP40) dimers associate with anionic lipids at the plasma membrane inner leaflet and undergo a dynamic and extensive self-oligomerization into the structural matrix layer. The MARV matrix layer confers the virion filamentous shape and stability but how host lipids modulate mVP40 oligomerization is mostly unknown. Using in vitro and cellular techniques, we present a mVP40 assembly model highlighting two distinct oligomerization interfaces: the (N-terminal domain [NTD] and C-terminal domain [CTD]) in mVP40. Cellular studies of NTD and CTD oligomerization interface mutants demonstrate the importance of each interface in matrix assembly. The assembly steps include protein trafficking to the plasma membrane, homo-multimerization that induced protein enrichment, plasma membrane fluidity changes, and elongations at the plasma membrane. An ascorbate peroxidase derivative (APEX)-transmission electron microscopy method was employed to closely assess the ultrastructural localization and formation of viral particles for wildtype mVP40 and NTD and CTD oligomerization interface mutants. Taken together, these studies present a mechanistic model of mVP40 oligomerization and assembly at the plasma membrane during virion assembly that requires interactions with phosphatidylserine for NTD–NTD interactions and phosphatidylinositol-4,5-bisphosphate for proper CTD–CTD interactions. These findings have broader implications in understanding budding of lipid-enveloped viruses from the host cell plasma membrane and potential strategies to target protein–protein or lipid–protein interactions to inhibit virus budding.
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Affiliation(s)
- Souad Amiar
- Department of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA
| | - Monica L Husby
- Department of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA
| | - Kaveesha J Wijesinghe
- Department of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA; Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Stephanie Angel
- Department of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA
| | - Nisha Bhattarai
- Department of Physics, Florida International University, Miami, Florida, USA
| | - Bernard S Gerstman
- Department of Physics, Florida International University, Miami, Florida, USA; Biomolecular Sciences Institute, Florida International University, Miami, Florida, USA
| | - Prem P Chapagain
- Department of Physics, Florida International University, Miami, Florida, USA; Biomolecular Sciences Institute, Florida International University, Miami, Florida, USA
| | - Sheng Li
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Robert V Stahelin
- Department of Medicinal Chemistry & Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA.
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24
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Landeras-Bueno S, Wasserman H, Oliveira G, VanAernum ZL, Busch F, Salie ZL, Wysocki VH, Andersen K, Saphire EO. Cellular mRNA triggers structural transformation of Ebola virus matrix protein VP40 to its essential regulatory form. Cell Rep 2021; 35:108986. [PMID: 33852858 PMCID: PMC8568338 DOI: 10.1016/j.celrep.2021.108986] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/02/2021] [Accepted: 03/23/2021] [Indexed: 12/28/2022] Open
Abstract
The Ebola virus matrix protein VP40 forms distinct structures linked to distinct functions in the virus life cycle. Dimeric VP40 is a structural protein associated with virus assembly, while octameric, ring-shaped VP40 is associated with transcriptional control. In this study, we show that suitable nucleic acid is sufficient to trigger a dynamic transformation of VP40 dimer into the octameric ring. Deep sequencing reveals a binding preference of the VP40 ring for the 3' untranslated region of cellular mRNA and a guanine- and adenine-rich binding motif. Complementary analyses of the nucleic-acid-induced VP40 ring by native mass spectrometry, electron microscopy, and X-ray crystal structures at 1.8 and 1.4 Å resolution reveal the stoichiometry of RNA binding, as well as an interface involving a key guanine nucleotide. The host factor-induced structural transformation of protein structure in response to specific RNA triggers in the Ebola virus life cycle presents unique opportunities for therapeutic inhibition.
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Affiliation(s)
| | - Hal Wasserman
- La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Glenn Oliveira
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Zachary L VanAernum
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Florian Busch
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Zhe Li Salie
- La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Vicki H Wysocki
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Kristian Andersen
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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25
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Clustered Lysine Residues of the Canine Distemper Virus Matrix Protein Regulate Membrane Association and Budding Activity. J Virol 2020; 95:JVI.01269-20. [PMID: 33028721 DOI: 10.1128/jvi.01269-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 10/03/2020] [Indexed: 01/06/2023] Open
Abstract
The canine distemper virus (CDV) matrix (M) protein is multifunctional; it orchestrates viral assembly and budding, drives the formation of virus-like particles (VLPs), regulates viral RNA synthesis, and may support additional functions. CDV M may assemble into dimers, where each protomer is constituted by N-terminal and C-terminal domains (NTD and CTD, respectively). Here, to investigate whether electrostatic interactions between CDV M and the plasma membrane (PM) may contribute to budding activity, selected surface-exposed positively charged lysine residues, which are located within a large basic patch of CTD, were replaced by amino acids with selected properties. We found that some M mutants harboring amino acids with neutral and positive charge (methionine and arginine, respectively) maintained full functionality, including proper interaction and localization with the PM as well as intact VLP and progeny virus production as demonstrated by employing a cell exit-complementation system. Conversely, while the overall structural integrity remained mostly unaltered, most of the nonconservative M variants (carrying a glutamic acid; negatively charged) exhibited a cytosolic phenotype secondary to the lack of interaction with the PM. Consequently, such M variants were entirely defective in VLP production and viral particle formation. Furthermore, the proteasome inhibitor bortezomib significantly reduced wild-type M-mediated VLP production. Nevertheless, in the absence of the compound, all engineered M lysine variants exhibited unaffected ubiquitination profiles, consistent with other residues likely involved in this functionally essential posttranslational modification. Altogether, our data identified multiple surface-exposed lysine residues located within a basic patch of CDV M-CTD, critically contributing to PM association and ensuing membrane budding activity.IMPORTANCE Although vaccines against some morbilliviruses exist, infections still occur, which can result in dramatic brain disease or fatal outcome. Postexposure prophylaxis with antivirals would support global vaccination campaigns. Unfortunately, there is no efficient antiviral drug currently approved. The matrix (M) protein of morbilliviruses coordinates viral assembly and egress through interaction with multiple cellular and viral components. However, molecular mechanisms supporting these functions remain poorly understood, which preclude the rationale design of inhibitors. Here, to investigate potential interactions between canine distemper virus (CDV) M and the plasma membrane (PM), we combined structure-guided mutagenesis of selected surface-exposed lysine residues with biochemical, cellular, and virological assays. We identified several lysines clustering in a basic patch microdomain of the CDV M C-terminal domain, which contributed to PM association and budding activity. Our findings provide novel mechanistic information of how morbilliviruses assemble and egress from infected cells, thereby delivering bases for future antiviral drug development.
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26
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Tran PTH, Asghar N, Höglund U, Larsson O, Haag L, Mirazimi A, Johansson M, Melik W. Development of a Multivalent Kunjin Virus Reporter Virus-Like Particle System Inducing Seroconversion for Ebola and West Nile Virus Proteins in Mice. Microorganisms 2020; 8:E1890. [PMID: 33260425 PMCID: PMC7760487 DOI: 10.3390/microorganisms8121890] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 12/26/2022] Open
Abstract
Kunjin virus (KUNV) is an attenuated strain of the severe neurotropic West Nile virus (WNV). The virus has a single-strand positive-sense RNA genome that encodes a polyprotein. Following gene expression, the polyprotein is cleaved into structural proteins for viral packaging and nonstructural proteins for viral replication and expression. Removal of the structural genes generate subgenomic replicons that maintain replication capacity. Co-expression of these replicons with the viral structural genes produces reporter virus-like particles (RVPs) which infect cells in a single round. In this study, we aimed to develop a system to generate multivalent RVPs based on KUNV to elicit an immune response against different viruses. We selected the Ebola virus (EBOV) glycoprotein (GP) and the matrix protein (VP40) genes, as candidates to be delivered by KUNV RVPs. Initially, we enhanced the production of KUNV RVPs by generating a stable cell line expressing the KUNV packaging system comprising capsid, precursor membrane, and envelope. Transfection of the DNA-based KUNV replicon into this cell line resulted in an enhanced RVP production. The replicon was expressed in the stable cell line to produce the RVPs that allowed the delivery of EBOV GP and VP40 genes into other cells. Finally, we immunized BALB/cN mice with RVPs, resulting in seroconversion for EBOV GP, EBOV VP40, WNV nonstructural protein 1, and WNV E protein. Thus, our study shows that KUNV RVPs may function as a WNV vaccine candidate and RVPs can be used as a gene delivery system in the development of future EBOV vaccines.
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Affiliation(s)
- Pham-Tue-Hung Tran
- School of Medical Science, Inflammatory Response and Infection Susceptibility Centre (iRiSC), Örebro University, 703 62 Örebro, Sweden; (P.-T.-H.T.); (N.A.); (M.J.)
| | - Naveed Asghar
- School of Medical Science, Inflammatory Response and Infection Susceptibility Centre (iRiSC), Örebro University, 703 62 Örebro, Sweden; (P.-T.-H.T.); (N.A.); (M.J.)
| | - Urban Höglund
- Adlego Biomedical AB, P.O. Box 42, 751 03 Uppsala, Sweden; (U.H.); (O.L.)
| | - Olivia Larsson
- Adlego Biomedical AB, P.O. Box 42, 751 03 Uppsala, Sweden; (U.H.); (O.L.)
| | - Lars Haag
- EM Unit (EMil), Department of Laboratory Medicine, Karolinska Institute, 171 77 Solna, Sweden;
| | - Ali Mirazimi
- Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, 141 52 Huddinge, Sweden;
- National Veterinary Institute, 751 89 Uppsala, Sweden
| | - Magnus Johansson
- School of Medical Science, Inflammatory Response and Infection Susceptibility Centre (iRiSC), Örebro University, 703 62 Örebro, Sweden; (P.-T.-H.T.); (N.A.); (M.J.)
| | - Wessam Melik
- School of Medical Science, Inflammatory Response and Infection Susceptibility Centre (iRiSC), Örebro University, 703 62 Örebro, Sweden; (P.-T.-H.T.); (N.A.); (M.J.)
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27
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Yoon YS, Jang Y, Hoenen T, Shin H, Lee Y, Kim M. Antiviral activity of sertindole, raloxifene and ibutamoren against transcription and replication-competent Ebola virus-like particles. BMB Rep 2020. [PMID: 31964466 PMCID: PMC7118351 DOI: 10.5483/bmbrep.2020.53.3.175] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A chemical library comprising 2,354 drug-like compounds was screened using a transcription and replication-competent virus-like particle (trVLP) system implementing the whole Ebola virus (EBOV) life cycle. Dose-dependent inhibition of Ebola trVLP replication was induced by 15 hit compounds, which primarily target different types of G protein-coupled receptors (GPCRs). Based on the chemical structure, the compounds were divided into three groups, diphenylmethane derivatives, promazine derivatives and chemicals with no conserved skeletons. The third group included sertindole, raloxifene, and ibutamoren showing prominent antiviral effects in cells. They downregulated the expression of viral proteins, including the VP40 matrix protein and the envelope glycoprotein. They also reduced the amount of EBOV-derived tetracistronic minigenome RNA incorporated into progeny trVLPs in the culture supernatant. Particularly, ibutamoren, which is a known agonist of growth hormone secretagogue receptor (GHSR), showed the most promising antiviral activity with a 50% effective concentration of 0.2 μM, a 50% cytotoxic concentration of 42.4 μM, and a selectivity index of 222.8. Here, we suggest a strategy for development of anti-EBOV therapeutics by adopting GHSR agonists as hit compounds.
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Affiliation(s)
- Yi-Seul Yoon
- Virus Research Group, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea
| | - Yejin Jang
- Virus Research Group, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea
| | - Thomas Hoenen
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems 17493, Germany
| | - Heegwon Shin
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Younghoon Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Meehyein Kim
- Virus Research Group, Korea Research Institute of Chemical Technology (KRICT), Daejeon 34114, Korea
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28
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Wu L, Jin D, Wang D, Jing X, Gong P, Qin Y, Chen M. The two-stage interaction of Ebola virus VP40 with nucleoprotein results in a switch from viral RNA synthesis to virion assembly/budding. Protein Cell 2020; 13:120-140. [PMID: 33141416 PMCID: PMC8783937 DOI: 10.1007/s13238-020-00764-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 07/06/2020] [Indexed: 11/28/2022] Open
Abstract
Ebola virus (EBOV) is an enveloped negative-sense RNA virus and a member of the filovirus family. Nucleoprotein (NP) expression alone leads to the formation of inclusion bodies (IBs), which are critical for viral RNA synthesis. The matrix protein, VP40, not only plays a critical role in virus assembly/budding, but also can regulate transcription and replication of the viral genome. However, the molecular mechanism by which VP40 regulates viral RNA synthesis and virion assembly/budding is unknown. Here, we show that within IBs the N-terminus of NP recruits VP40 and is required for VLP-containing NP release. Furthermore, we find four point mutations (L692A, P697A, P698A and W699A) within the C-terminal hydrophobic core of NP result in a stronger VP40-NP interaction within IBs, sequestering VP40 within IBs, reducing VP40-VLP egress, abolishing the incorporation of NC-like structures into VP40-VLP, and inhibiting viral RNA synthesis, suggesting that the interaction of N-terminus of NP with VP40 induces a conformational change in the C-terminus of NP. Consequently, the C-terminal hydrophobic core of NP is exposed and binds VP40, thereby inhibiting RNA synthesis and initiating virion assembly/budding.
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Affiliation(s)
- Linjuan Wu
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Dongning Jin
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Dan Wang
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Xuping Jing
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Peng Gong
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yali Qin
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
| | - Mingzhou Chen
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
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29
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Wan W, Clarke M, Norris MJ, Kolesnikova L, Koehler A, Bornholdt ZA, Becker S, Saphire EO, Briggs JA. Ebola and Marburg virus matrix layers are locally ordered assemblies of VP40 dimers. eLife 2020; 9:59225. [PMID: 33016878 PMCID: PMC7588233 DOI: 10.7554/elife.59225] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 10/02/2020] [Indexed: 01/28/2023] Open
Abstract
Filoviruses such as Ebola and Marburg virus bud from the host membrane as enveloped virions. This process is achieved by the matrix protein VP40. When expressed alone, VP40 induces budding of filamentous virus-like particles, suggesting that localization to the plasma membrane, oligomerization into a matrix layer, and generation of membrane curvature are intrinsic properties of VP40. There has been no direct information on the structure of VP40 matrix layers within viruses or virus-like particles. We present structures of Ebola and Marburg VP40 matrix layers in intact virus-like particles, and within intact Marburg viruses. VP40 dimers assemble extended chains via C-terminal domain interactions. These chains stack to form 2D matrix lattices below the membrane surface. These lattices form a patchwork assembly across the membrane and suggesting that assembly may begin at multiple points. Our observations define the structure and arrangement of the matrix protein layer that mediates formation of filovirus particles.
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Affiliation(s)
- William Wan
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Mairi Clarke
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Michael J Norris
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, United States
| | - Larissa Kolesnikova
- Institut für Virologie, Philipps-Universität Marburg, Hans-Meerwein-Straße, Marburg, Germany
| | - Alexander Koehler
- Institut für Virologie, Philipps-Universität Marburg, Hans-Meerwein-Straße, Marburg, Germany
| | | | - Stephan Becker
- Institut für Virologie, Philipps-Universität Marburg, Hans-Meerwein-Straße, Marburg, Germany
| | - Erica Ollmann Saphire
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, United States
| | - John Ag Briggs
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
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The Minor Matrix Protein VP24 from Ebola Virus Lacks Direct Lipid-Binding Properties. Viruses 2020; 12:v12080869. [PMID: 32784484 PMCID: PMC7472063 DOI: 10.3390/v12080869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/02/2020] [Accepted: 08/05/2020] [Indexed: 11/17/2022] Open
Abstract
Viral protein 24 (VP24) from Ebola virus (EBOV) was first recognized as a minor matrix protein that associates with cellular membranes. However, more recent studies shed light on its roles in inhibiting viral genome transcription and replication, facilitating nucleocapsid assembly and transport, and interfering with immune responses in host cells through downregulation of interferon (IFN)-activated genes. Thus, whether VP24 is a peripheral protein with lipid-binding ability for matrix layer recruitment has not been explored. Here, we examined the lipid-binding ability of VP24 with a number of lipid-binding assays. The results indicated that VP24 lacked the ability to associate with lipids tested regardless of VP24 posttranslational modifications. We further demonstrate that the presence of the EBOV major matrix protein VP40 did not promote VP24 membrane association in vitro or in cells. Further, no protein–protein interactions between VP24 and VP40 were detected by co-immunoprecipitation. Confocal imaging and cellular membrane fractionation analyses in human cells suggested VP24 did not specifically localize at the plasma membrane inner leaflet. Overall, we provide evidence that EBOV VP24 is not a lipid-binding protein and its presence in the viral matrix layer is likely not dependent on direct lipid interactions.
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Ivanov A, Ramanathan P, Parry C, Ilinykh PA, Lin X, Petukhov M, Obukhov Y, Ammosova T, Amarasinghe GK, Bukreyev A, Nekhai S. Global phosphoproteomic analysis of Ebola virions reveals a novel role for VP35 phosphorylation-dependent regulation of genome transcription. Cell Mol Life Sci 2020; 77:2579-2603. [PMID: 31562565 PMCID: PMC7101265 DOI: 10.1007/s00018-019-03303-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 08/26/2019] [Accepted: 09/16/2019] [Indexed: 12/27/2022]
Abstract
Ebola virus (EBOV) causes severe human disease with a high case fatality rate. The balance of evidence implies that the virus circulates in bats. The molecular basis for host-viral interactions, including the role for phosphorylation during infections, is largely undescribed. To address this, and to better understand the biology of EBOV, the phosphorylation of EBOV proteins was analyzed in virions purified from infected monkey Vero-E6 cells and bat EpoNi/22.1 cells using high-resolution mass spectrometry. All EBOV structural proteins were detected with high coverage, along with phosphopeptides. Phosphorylation sites were identified in all viral structural proteins. Comparison of EBOV protein phosphorylation in monkey and bat cells showed only partial overlap of phosphorylation sites, with shared sites found in NP, VP35, and VP24 proteins, and no common sites in the other proteins. Three-dimensional structural models were built for NP, VP35, VP40, GP, VP30 and VP24 proteins using available crystal structures or by de novo structure prediction to elucidate the potential role of the phosphorylation sites. Phosphorylation of one of the identified sites in VP35, Thr-210, was demonstrated to govern the transcriptional activity of the EBOV polymerase complex. Thr-210 phosphorylation was also shown to be important for VP35 interaction with NP. This is the first study to compare phosphorylation of all EBOV virion proteins produced in primate versus bat cells, and to demonstrate the role of VP35 phosphorylation in the viral life cycle. The results uncover a novel mechanism of EBOV transcription and identify novel targets for antiviral drug development.
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Affiliation(s)
- Andrey Ivanov
- Center for Sickle Cell Disease, Howard University, 2201 Georgia Ave., N.W., Suite 321D, Washington, D.C., 20059, USA
| | - Palaniappan Ramanathan
- Department of Pathology, University of Texas, Medical Branch at Galveston, 301 University Boulevard, Galveston, TX, 77574-0609, USA
| | - Christian Parry
- Center for Sickle Cell Disease, Howard University, 2201 Georgia Ave., N.W., Suite 321D, Washington, D.C., 20059, USA
- Department of Microbiology, Howard University, Washington, D.C., 20059, USA
| | - Philipp A Ilinykh
- Department of Pathology, University of Texas, Medical Branch at Galveston, 301 University Boulevard, Galveston, TX, 77574-0609, USA
| | - Xionghao Lin
- Center for Sickle Cell Disease, Howard University, 2201 Georgia Ave., N.W., Suite 321D, Washington, D.C., 20059, USA
- College of Dentistry, Howard University, Washington, D.C., 20059, USA
| | - Michael Petukhov
- Division of Molecular and Radiation Biophysics, Russian Nuclear Physics Institute Named After B. P. Konstantinov, National Research Center "Kurchatov Institute", Gatchina, 188300, Russia
- Russian Scientific Center of Radiology and Surgical Technologies Named After A. M. Granov, St. Petersburg, 197758, Russia
| | - Yuri Obukhov
- Center for Sickle Cell Disease, Howard University, 2201 Georgia Ave., N.W., Suite 321D, Washington, D.C., 20059, USA
| | - Tatiana Ammosova
- Center for Sickle Cell Disease, Howard University, 2201 Georgia Ave., N.W., Suite 321D, Washington, D.C., 20059, USA
- Department of Medicine, Howard University, Washington, D.C., 20059, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Alexander Bukreyev
- Department of Pathology, University of Texas, Medical Branch at Galveston, 301 University Boulevard, Galveston, TX, 77574-0609, USA.
- Department of Microbiology and Immunology, University of Texas, Medical Branch at Galveston, 301 University Boulevard, Galveston, TX, 77574-0609, USA.
- Galveston National Laboratory, University of Texas, Medical Branch at Galveston, 301 University Boulevard, Galveston, TX, 77574-0609, USA.
| | - Sergei Nekhai
- Center for Sickle Cell Disease, Howard University, 2201 Georgia Ave., N.W., Suite 321D, Washington, D.C., 20059, USA.
- Department of Microbiology, Howard University, Washington, D.C., 20059, USA.
- Department of Medicine, Howard University, Washington, D.C., 20059, USA.
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Impact of Měnglà Virus Proteins on Human and Bat Innate Immune Pathways. J Virol 2020; 94:JVI.00191-20. [PMID: 32295912 DOI: 10.1128/jvi.00191-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 04/07/2020] [Indexed: 12/31/2022] Open
Abstract
Měnglà virus (MLAV), identified in Rousettus bats, is a phylogenetically distinct member of the family Filoviridae Because the filoviruses Ebola virus (EBOV) and Marburg virus (MARV) modulate host innate immunity, MLAV VP35, VP40, and VP24 proteins were compared with their EBOV and MARV homologs for innate immune pathway modulation. In human and Rousettus cells, MLAV VP35 behaved like EBOV and MARV VP35s, inhibiting virus-induced activation of the interferon beta (IFN-β) promoter and interferon regulatory factor 3 (IRF3) phosphorylation. MLAV VP35 also interacted with PACT, a host protein engaged by EBOV VP35 to inhibit RIG-I signaling. MLAV VP35 also inhibits PKR activation. MLAV VP40 was demonstrated to inhibit type I IFN-induced gene expression in human and bat cells. It blocked STAT1 tyrosine phosphorylation induced either by type I IFN or overexpressed Jak1, paralleling MARV VP40. MLAV VP40 also inhibited virus-induced IFN-β promoter activation, a property shared by MARV VP40 and EBOV VP24. A Jak kinase inhibitor did not recapitulate this inhibition in the absence of viral proteins. Therefore, inhibition of Jak-STAT signaling is insufficient to explain inhibition of IFN-β promoter activation. MLAV VP24 did not inhibit IFN-induced gene expression or bind karyopherin α proteins, properties of EBOV VP24. MLAV VP24 differed from MARV VP24 in that it failed to interact with Keap1 or activate an antioxidant response element reporter gene due to the absence of a Keap1-binding motif. These functional observations support a closer relationship of MLAV to MARV than to EBOV but also are consistent with MLAV belonging to a distinct genus.IMPORTANCE EBOV and MARV, members of the family Filoviridae, are highly pathogenic zoonotic viruses that cause severe disease in humans. Both viruses use several mechanisms to modulate the host innate immune response, and these likely contribute to the severity of disease. Here, we demonstrate that MLAV, a filovirus newly discovered in a bat, suppresses antiviral type I interferon responses in both human and bat cells. Inhibitory activities are possessed by MLAV VP35 and VP40, which parallels how MARV blocks IFN responses. However, whereas MARV activates cellular antioxidant responses through an interaction between its VP24 protein and host protein Keap1, MLAV VP24 lacks a Keap1-binding motif and fails to activate this cytoprotective response. These data indicate that MLAV possesses immune-suppressing functions that could facilitate human infection. They also support the placement of MLAV in a different genus than either EBOV or MARV.
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A Conserved Tryptophan in the Ebola Virus Matrix Protein C-Terminal Domain Is Required for Efficient Virus-Like Particle Formation. Pathogens 2020; 9:pathogens9050402. [PMID: 32455873 PMCID: PMC7281420 DOI: 10.3390/pathogens9050402] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/19/2020] [Accepted: 05/19/2020] [Indexed: 02/05/2023] Open
Abstract
The Ebola virus (EBOV) harbors seven genes, one of which is the matrix protein eVP40, a peripheral protein that is sufficient to induce the formation of virus-like particles from the host cell plasma membrane. eVP40 can form different structures to fulfil different functions during the viral life cycle, although the structural dynamics of eVP40 that warrant dimer, hexamer, and octamer formation are still poorly understood. eVP40 has two conserved Trp residues at positions 95 and 191. The role of Trp95 has been characterized in depth as it serves as an important residue in eVP40 oligomer formation. To gain insight into the functional role of Trp191 in eVP40, we prepared mutations of Trp191 (W191A or W191F) to determine the effects of mutation on eVP40 plasma membrane localization and budding as well as eVP40 oligomerization. These in vitro and cellular experiments were complemented by molecular dynamics simulations of the wild-type (WT) eVP40 structure versus that of W191A. Taken together, Trp is shown to be a critical amino acid at position 191 as mutation to Ala reduces the ability of VP40 to localize to the plasma membrane inner leaflet and form new virus-like particles. Further, mutation of Trp191 to Ala or Phe shifted the in vitro equilibrium to the octamer form by destabilizing Trp191 interactions with nearby residues. This study has shed new light on the importance of interdomain interactions in stability of the eVP40 structure and the critical nature of timing of eVP40 oligomerization for plasma membrane localization and viral budding.
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Identification of Novel Adjuvants for Ebola Virus-Like Particle Vaccine. Vaccines (Basel) 2020; 8:vaccines8020215. [PMID: 32397625 PMCID: PMC7349346 DOI: 10.3390/vaccines8020215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/03/2020] [Accepted: 05/05/2020] [Indexed: 11/16/2022] Open
Abstract
Ebola virus disease is a severe disease, often fatal, with a mortality rate of up to 90%. Presently, effective treatment and safe prevention options for Ebola virus disease are not available. Therefore, there is an urgent need to develop control measures to prevent or limit future Ebola virus outbreaks. Ebola virus protein-based virus-like particle (VLP) and inactivated whole virion vaccines have demonstrated efficacy in animal models, and the addition of appropriate adjuvants may provide additional benefits to these vaccines, including enhanced immune responses. In this study, we screened 24 compounds from injectable excipients approved for human use in Japan and identified six compounds that significantly enhanced the humoral response to Ebola VLP vaccine in a murine model. Our novel adjuvant candidates for Ebola VLP vaccine have already been demonstrated to be safe when administered intramuscularly or subcutaneously, and therefore, they are closer to clinical trials than adjuvants whose safety profiles are unknown.
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35
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Wijesinghe KJ, McVeigh L, Husby ML, Bhattarai N, Ma J, Gerstman BS, Chapagain PP, Stahelin RV. Mutation of Hydrophobic Residues in the C-Terminal Domain of the Marburg Virus Matrix Protein VP40 Disrupts Trafficking to the Plasma Membrane. Viruses 2020; 12:v12040482. [PMID: 32344654 PMCID: PMC7232359 DOI: 10.3390/v12040482] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/14/2020] [Accepted: 04/22/2020] [Indexed: 12/13/2022] Open
Abstract
Marburg virus (MARV) is a lipid-enveloped negative sense single stranded RNA virus, which can cause a deadly hemorrhagic fever. MARV encodes seven proteins, including VP40 (mVP40), a matrix protein that interacts with the cytoplasmic leaflet of the host cell plasma membrane. VP40 traffics to the plasma membrane inner leaflet, where it assembles to facilitate the budding of viral particles. VP40 is a multifunctional protein that interacts with several host proteins and lipids to complete the viral replication cycle, but many of these host interactions remain unknown or are poorly characterized. In this study, we investigated the role of a hydrophobic loop region in the carboxy-terminal domain (CTD) of mVP40 that shares sequence similarity with the CTD of Ebola virus VP40 (eVP40). These conserved hydrophobic residues in eVP40 have been previously shown to be critical to plasma membrane localization and membrane insertion. An array of cellular experiments and confirmatory in vitro work strongly suggests proper orientation and hydrophobic residues (Phe281, Leu283, and Phe286) in the mVP40 CTD are critical to plasma membrane localization. In line with the different functions proposed for eVP40 and mVP40 CTD hydrophobic residues, molecular dynamics simulations demonstrate large flexibility of residues in the EBOV CTD whereas conserved mVP40 hydrophobic residues are more restricted in their flexibility. This study sheds further light on important amino acids and structural features in mVP40 required for its plasma membrane localization as well as differences in the functional role of CTD amino acids in eVP40 and mVP40.
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Affiliation(s)
- Kaveesha J. Wijesinghe
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; (K.J.W.); (L.M.)
| | - Luke McVeigh
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; (K.J.W.); (L.M.)
| | - Monica L. Husby
- Department of Medicinal Chemistry and Molecular Pharmacology and the Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA;
| | - Nisha Bhattarai
- Department of Physics, Florida International University, Miami, FL 33199, USA; (N.B.); (B.S.G.); (P.P.C.)
| | - Jia Ma
- Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907, USA;
| | - Bernard S. Gerstman
- Department of Physics, Florida International University, Miami, FL 33199, USA; (N.B.); (B.S.G.); (P.P.C.)
- Biomolecules Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Prem P. Chapagain
- Department of Physics, Florida International University, Miami, FL 33199, USA; (N.B.); (B.S.G.); (P.P.C.)
- Biomolecules Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Robert V. Stahelin
- Department of Medicinal Chemistry and Molecular Pharmacology and the Purdue Institute for Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA;
- Correspondence: ; Tel.: +1-765-494-4152
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Lin AE, Diehl WE, Cai Y, Finch CL, Akusobi C, Kirchdoerfer RN, Bollinger L, Schaffner SF, Brown EA, Saphire EO, Andersen KG, Kuhn JH, Luban J, Sabeti PC. Reporter Assays for Ebola Virus Nucleoprotein Oligomerization, Virion-Like Particle Budding, and Minigenome Activity Reveal the Importance of Nucleoprotein Amino Acid Position 111. Viruses 2020; 12:E105. [PMID: 31952352 PMCID: PMC7019320 DOI: 10.3390/v12010105] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 01/17/2023] Open
Abstract
For highly pathogenic viruses, reporter assays that can be rapidly performed are critically needed to identify potentially functional mutations for further study under maximal containment (e.g., biosafety level 4 [BSL-4]). The Ebola virus nucleoprotein (NP) plays multiple essential roles during the viral life cycle, yet few tools exist to study the protein under BSL-2 or equivalent containment. Therefore, we adapted reporter assays to measure NP oligomerization and virion-like particle (VLP) production in live cells and further measured transcription and replication using established minigenome assays. As a proof-of-concept, we examined the NP-R111C substitution, which emerged during the 2013‒2016 Western African Ebola virus disease epidemic and rose to high frequency. NP-R111C slightly increased NP oligomerization and VLP budding but slightly decreased transcription and replication. By contrast, a synthetic charge-reversal mutant, NP-R111E, greatly increased oligomerization but abrogated transcription and replication. These results are intriguing in light of recent structures of NP oligomers, which reveal that the neighboring residue, K110, forms a salt bridge with E349 on adjacent NP molecules. By developing and utilizing multiple reporter assays, we find that the NP-111 position mediates a complex interplay between NP's roles in protein structure, virion budding, and transcription and replication.
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Affiliation(s)
- Aaron E. Lin
- Harvard Program in Virology, Harvard Medical School, Boston, MA 02115, USA
- Department of Organismic and Evolutionary Biology, FAS Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA; (S.F.S.); (E.A.B.)
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - William E. Diehl
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA; (W.E.D.); (J.L.)
| | - Yingyun Cai
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, MD 21702, USA; (Y.C.); (C.L.F.); (L.B.); (J.H.K.)
| | - Courtney L. Finch
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, MD 21702, USA; (Y.C.); (C.L.F.); (L.B.); (J.H.K.)
| | - Chidiebere Akusobi
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02120, USA;
| | | | - Laura Bollinger
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, MD 21702, USA; (Y.C.); (C.L.F.); (L.B.); (J.H.K.)
| | - Stephen F. Schaffner
- Department of Organismic and Evolutionary Biology, FAS Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA; (S.F.S.); (E.A.B.)
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Elizabeth A. Brown
- Department of Organismic and Evolutionary Biology, FAS Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA; (S.F.S.); (E.A.B.)
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Kristian G. Andersen
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, La Jolla, CA 92037, USA;
- Scripps Translational Science Institute, La Jolla, CA 92037, USA
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, MD 21702, USA; (Y.C.); (C.L.F.); (L.B.); (J.H.K.)
| | - Jeremy Luban
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA; (W.E.D.); (J.L.)
| | - Pardis C. Sabeti
- Harvard Program in Virology, Harvard Medical School, Boston, MA 02115, USA
- Department of Organismic and Evolutionary Biology, FAS Center for Systems Biology, Harvard University, Cambridge, MA 02138, USA; (S.F.S.); (E.A.B.)
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
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The Ebola Virus Nucleoprotein Recruits the Nuclear RNA Export Factor NXF1 into Inclusion Bodies to Facilitate Viral Protein Expression. Cells 2020; 9:cells9010187. [PMID: 31940815 PMCID: PMC7017048 DOI: 10.3390/cells9010187] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/07/2020] [Accepted: 01/09/2020] [Indexed: 01/12/2023] Open
Abstract
Ebola virus (EBOV) causes severe outbreaks of viral hemorrhagic fever in humans. While virus-host interactions are promising targets for antivirals, there is only limited knowledge regarding the interactions of EBOV with cellular host factors. Recently, we performed a genome-wide siRNA screen that identified the nuclear RNA export factor 1 (NXF1) as an important host factor for the EBOV life cycle. NXF1 is a major component of the nuclear mRNA export pathway that is usurped by many viruses whose life cycles include nuclear stages. However, the role of NXF1 in the life cycle of EBOV, a virus replicating in cytoplasmic inclusion bodies, remains unknown. In order to better understand the role of NXF1 in the EBOV life cycle, we performed a combination of co-immunoprecipitation and double immunofluorescence assays to characterize the interactions of NXF1 with viral proteins and RNAs. Additionally, using siRNA-mediated knockdown of NXF1 together with functional assays, we analyzed the role of NXF1 in individual aspects of the virus life cycle. With this approach we identified the EBOV nucleoprotein (NP) as a viral interaction partner of NXF1. Further studies revealed that NP interacts with the RNA-binding domain of NXF1 and competes with RNA for this interaction. Co-localization studies showed that RNA binding-deficient, but not wildtype NXF1, accumulates in NP-derived inclusion bodies, and knockdown experiments demonstrated that NXF1 is necessary for viral protein expression, but not for viral RNA synthesis. Finally, our results showed that NXF1 interacts with viral mRNAs, but not with viral genomic RNAs. Based on these results we suggest a model whereby NXF1 is recruited into inclusion bodies to promote the export of viral mRNA:NXF1 complexes from these sites. This would represent a novel function for NXF1 in the life cycle of cytoplasmically replicating viruses, and may provide a basis for new therapeutic approaches against EBOV, and possibly other emerging viruses.
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[Molecular mechanisms of highly pathogenic viruses' replication and their applications for a novel drug discovery]. Uirusu 2020; 70:69-82. [PMID: 33967116 DOI: 10.2222/jsv.70.69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Productive (lytic) replication of DNA viruses elicits host cell DNA damage responses, which cause both beneficial and detrimental effects on viral replication. Viruses utilize them and selectively cancel the 'noisy' downstream signaling pathways, leading to maintain high S-phase CDK activities required for viral replication. To achieve this fine tuning of cellular environment, herpesviruses encode many (>70) genes in their genome, which are expressed in a strictly regulated temporal cascade (immediate-early, early, and late). Here, I introduce and discuss how Epstein-Barr virus, an oncogenic herpesvirus, hijacks the cellular environment and adapt it for the progeny production.
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Ebola virus disease: An emerging and re-emerging viral threat. J Autoimmun 2019; 106:102375. [PMID: 31806422 DOI: 10.1016/j.jaut.2019.102375] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/19/2019] [Accepted: 11/21/2019] [Indexed: 12/21/2022]
Abstract
The genus Ebolavirus from the family Filoviridae is composed of five species including Sudan ebolavirus, Reston ebolavirus, Bundibugyo ebolavirus, Taï Forest ebolavirus, and Ebola virus (previously known as Zaire ebolavirus). These viruses have a large non-segmented, negative-strand RNA of approximately 19 kb that encodes for glycoproteins (i.e., GP, sGP, ssGP), nucleoproteins, virion proteins (i.e., VP 24, 30,40) and an RNA dependent RNA polymerase. These viruses have become a global health concern because of mortality, their rapid dissemination, new outbreaks in West-Africa, and the emergence of a new condition known as "Post-Ebola virus disease syndrome" that resembles inflammatory and autoimmune conditions such as rheumatoid arthritis, systemic lupus erythematosus and spondyloarthritis with uveitis. However, there are many gaps in the understanding of the mechanisms that may induce the development of such autoimmune-like syndromes. Some of these mechanisms may include a high formation of neutrophil extracellular traps, an uncontrolled "cytokine storm", and the possible formation of auto-antibodies. The likely appearance of autoimmune phenomena in Ebola survivors suppose a new challenge in the management and control of this disease and opens a new field of research in a special subgroup of patients. Herein, the molecular biology, pathogenesis, clinical manifestations, and treatment of Ebola virus disease are reviewed and some strategies for control of disease are discussed.
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40
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Nanbo A, Ohba Y. Budding of Ebola Virus Particles Requires the Rab11-Dependent Endocytic Recycling Pathway. J Infect Dis 2019; 218:S388-S396. [PMID: 30476249 PMCID: PMC6249604 DOI: 10.1093/infdis/jiy460] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
The Ebola virus-encoded major matrix protein VP40 traffics to the plasma membrane, which leads to the formation of filamentous viral particles and subsequent viral egress. However, the cellular machineries underlying this process are not fully understood. In the present study, we have assessed the role of host endocytic recycling in Ebola virus particle formation. We found that a small GTPase Rab11, which regulates recycling of molecules among the trans-Golgi network, recycling endosomes, and the plasma membrane, was incorporated in Ebola virus-like particles. Although Rab11 predominantly localized in the perinuclear region, it distributed diffusely in the cytoplasm and partly localized in the periphery of the cells transiently expressing VP40. In contrast, Rab11 exhibited a perinuclear distribution when 2 VP40 derivatives that lack ability to traffic to the plasma membrane were expressed. Finally, expression of a dominant-negative form of Rab11 or knockdown of Rab11 inhibited both VP40-induced clusters at the plasma membrane and release of viral-like particles. Taken together, our findings demonstrate that Ebola virus exploits host endocytic recycling machinery to facilitate the trafficking of VP40 to the cell surface and the subsequent release of viral-like particles for its establishment of efficient viral egress.
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Affiliation(s)
- Asuka Nanbo
- Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Yusuke Ohba
- Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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41
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Pastor AR, González-Domínguez G, Díaz-Salinas MA, Ramírez OT, Palomares LA. Defining the multiplicity and time of infection for the production of Zaire Ebola virus-like particles in the insect cell-baculovirus expression system. Vaccine 2019; 37:6962-6969. [PMID: 31262589 DOI: 10.1016/j.vaccine.2019.06.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 04/24/2019] [Accepted: 06/14/2019] [Indexed: 11/16/2022]
Abstract
The Ebola virus disease is a public health challenge. To date, the only available treatments are medical support or the emergency administration of experimental drugs. The absence of licensed vaccines against Ebola virus impedes the prevention of infection. Vaccines based on recombinant virus-like particles (VLP) are a promising alternative. The Zaire Ebola virus serotype (ZEBOV) is the most aggressive with the highest mortality rates. Production of ZEBOV-VLP has been accomplished in mammalian and insect cells by the recombinant coexpression of three structural proteins, the glycoprotein (GP), the matrix structural protein VP40, and the nucleocapsid protein (NP). However, specific conditions to manipulate protein concentrations and improve assembly into VLP have not been determined to date. Here, we used a design of experiments (DoE) approach to determine the best MOI and TOI for three recombinant baculoviruses: bac-GP, bac-VP40 and bac-NP, each coding for one of the main structural proteins of ZEBOV. We identified two conditions where the simultaneous expression of the three recombinant proteins was observed. Interestingly, a temporal and stoichiometric interplay between the three structural proteins was observed. VP40 was required for the correct assembly of ZEBOV-VLP. High NP concentrations reduced the accumulation of GP, which has been reported to be necessary for inducing a protective immune response. Electron microscopy showed that the ZEBOV-VLP produced were morphologically similar to the native virus micrographs previously reported in the literature. A strategy for producing ZEBOV in insect cells, which consists in using a high MOI of bac-VP40 and bac-GP, and reducing expression of NP, either by delaying infection or reducing the MOI of bac-NP, was the most adequate for the production of VLP.
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Affiliation(s)
- Ana Ruth Pastor
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Ave. Universidad 2001, Cuernavaca, Morelos 62210, Mexico.
| | - Gonzalo González-Domínguez
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Ave. Universidad 2001, Cuernavaca, Morelos 62210, Mexico; Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico.
| | - Marco A Díaz-Salinas
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Ave. Universidad 2001, Cuernavaca, Morelos 62210, Mexico.
| | - Octavio T Ramírez
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Ave. Universidad 2001, Cuernavaca, Morelos 62210, Mexico.
| | - Laura A Palomares
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Ave. Universidad 2001, Cuernavaca, Morelos 62210, Mexico.
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42
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Urata S, Ishikawa T, Yasuda J. Roles of YIGL sequence of Ebola virus VP40 on genome replication and particle production. J Gen Virol 2019; 100:1099-1111. [PMID: 31184566 DOI: 10.1099/jgv.0.001286] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ebola virus (EBOV) VP40 is a major driving force of nascent virion production and a negative regulator of genome replication/transcription. Here, we showed that the YIGL sequence at the C-terminus of EBOV VP40 is important for virus-like particle (VLP) production and the regulation of genome replication/transcription. Accordingly, a mutation in the YIGL sequence caused defects in VLP production and genome replication/transcription. The residues I293 and L295 in the YIGL sequence were particularly critical for VLP production. Furthermore, an in silico analysis indicated that the amino acids surrounding the YIGL sequence contribute to intramolecular interactions within VP40. Among those surrounding residues, F209 was shown to be critical for VLP production. These results suggested that the VP40 YIGL sequence regulates two different viral replication steps, VLP production and genome replication/transcription, and the nearby residue F209 influences VLP production.
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Affiliation(s)
- Shuzo Urata
- Department of Emerging Infectious Diseasesn, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan.,National Research Center for the Control and Prevention of Infectious Diseases (CCPID), Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Takeshi Ishikawa
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Jiro Yasuda
- National Research Center for the Control and Prevention of Infectious Diseases (CCPID), Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan.,Graduate School of Biomedical Sciences and Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan.,Department of Emerging Infectious Diseasesn, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
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43
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Abstract
This chapter reviews our current knowledge about the spatiotemporal assembly of filoviral particles. We will follow particles from nucleocapsid entry into the cytoplasm until the nucleocapsids are enveloped at the plasma membrane. We will also highlight the currently open scientific questions surrounding filovirus assembly.
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44
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Pleet ML, DeMarino C, Stonier SW, Dye JM, Jacobson S, Aman MJ, Kashanchi F. Extracellular Vesicles and Ebola Virus: A New Mechanism of Immune Evasion. Viruses 2019; 11:v11050410. [PMID: 31052499 PMCID: PMC6563240 DOI: 10.3390/v11050410] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 04/29/2019] [Accepted: 05/01/2019] [Indexed: 02/06/2023] Open
Abstract
Ebola virus (EBOV) disease can result in a range of symptoms anywhere from virtually asymptomatic to severe hemorrhagic fever during acute infection. Additionally, spans of asymptomatic persistence in recovering survivors is possible, during which transmission of the virus may occur. In acute infection, substantial cytokine storm and bystander lymphocyte apoptosis take place, resulting in uncontrolled, systemic inflammation in affected individuals. Recently, studies have demonstrated the presence of EBOV proteins VP40, glycoprotein (GP), and nucleoprotein (NP) packaged into extracellular vesicles (EVs) during infection. EVs containing EBOV proteins have been shown to induce apoptosis in recipient immune cells, as well as contain pro-inflammatory cytokines. In this manuscript, we review the current field of knowledge on EBOV EVs including the mechanisms of their biogenesis, their cargo and their effects in recipient cells. Furthermore, we discuss some of the effects that may be induced by EBOV EVs that have not yet been characterized and highlight the remaining questions and future directions.
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Affiliation(s)
- Michelle L Pleet
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA.
| | - Catherine DeMarino
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA.
| | - Spencer W Stonier
- Department, Emergent BioSolutions, Gaithersburg, MD 20879, USA.
- Virology Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21702, USA.
| | - John M Dye
- Virology Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD 21702, USA.
| | - Steven Jacobson
- Viral Immunology Section, Neuroimmunology Branch, National Institute for Neurological Disease and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - M Javad Aman
- Department. Integrated BioTherapeutics, Inc., Gaithersburg, MD 20850, USA.
| | - Fatah Kashanchi
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA.
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45
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Kämper L, Zierke L, Schmidt ML, Müller A, Wendt L, Brandt J, Hartmann E, Braun S, Holzerland J, Groseth A, Hoenen T. Assessment of the function and intergenus-compatibility of Ebola and Lloviu virus proteins. J Gen Virol 2019; 100:760-772. [DOI: 10.1099/jgv.0.001261] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Lennart Kämper
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Lukas Zierke
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Marie Luisa Schmidt
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Andreas Müller
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Lisa Wendt
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Janine Brandt
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Eric Hartmann
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Stefanie Braun
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Julia Holzerland
- 2 Junior Research Group Arenavirus Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Allison Groseth
- 2 Junior Research Group Arenavirus Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
| | - Thomas Hoenen
- 1 Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald – Insel Riems, Germany
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46
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Salata C, Calistri A, Alvisi G, Celestino M, Parolin C, Palù G. Ebola Virus Entry: From Molecular Characterization to Drug Discovery. Viruses 2019; 11:v11030274. [PMID: 30893774 PMCID: PMC6466262 DOI: 10.3390/v11030274] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 03/15/2019] [Accepted: 03/16/2019] [Indexed: 02/06/2023] Open
Abstract
Ebola Virus Disease (EVD) is one of the most lethal transmissible infections, characterized by a high fatality rate, and caused by a member of the Filoviridae family. The recent large outbreak of EVD in Western Africa (2013–2016) highlighted the worldwide threat represented by the disease and its impact on global public health and the economy. The development of highly needed anti-Ebola virus antivirals has been so far hampered by the shortage of tools to study their life cycle in vitro, allowing to screen for potential active compounds outside a biosafety level-4 (BSL-4) containment. Importantly, the development of surrogate models to study Ebola virus entry in a BSL-2 setting, such as viral pseudotypes and Ebola virus-like particles, tremendously boosted both our knowledge of the viral life cycle and the identification of promising antiviral compounds interfering with viral entry. In this context, the combination of such surrogate systems with large-scale small molecule compounds and haploid genetic screenings, as well as rational drug design and drug repurposing approaches will prove priceless in our quest for the development of a treatment for EVD.
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Affiliation(s)
- Cristiano Salata
- Department of Molecular Medicine, University of Padova, IT-35121 Padova, Italy.
| | - Arianna Calistri
- Department of Molecular Medicine, University of Padova, IT-35121 Padova, Italy.
| | - Gualtiero Alvisi
- Department of Molecular Medicine, University of Padova, IT-35121 Padova, Italy.
| | - Michele Celestino
- Department of Molecular Medicine, University of Padova, IT-35121 Padova, Italy.
| | - Cristina Parolin
- Department of Molecular Medicine, University of Padova, IT-35121 Padova, Italy.
| | - Giorgio Palù
- Department of Molecular Medicine, University of Padova, IT-35121 Padova, Italy.
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47
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Gordon TB, Hayward JA, Marsh GA, Baker ML, Tachedjian G. Host and Viral Proteins Modulating Ebola and Marburg Virus Egress. Viruses 2019; 11:v11010025. [PMID: 30609802 PMCID: PMC6357148 DOI: 10.3390/v11010025] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/21/2018] [Accepted: 01/01/2019] [Indexed: 12/11/2022] Open
Abstract
The filoviruses Ebolavirus and Marburgvirus are among the deadliest viral pathogens known to infect humans, causing emerging diseases with fatality rates of up to 90% during some outbreaks. The replication cycles of these viruses are comprised of numerous complex molecular processes and interactions with their human host, with one key feature being the means by which nascent virions exit host cells to spread to new cells and ultimately to a new host. This review focuses on our current knowledge of filovirus egress and the viral and host factors and processes that are involved. Within the virus, these factors consist of the major matrix protein, viral protein 40 (VP40), which is necessary and sufficient for viral particle release, and nucleocapsid and glycoprotein that interact with VP40 to promote egress. In the host cell, some proteins are hijacked by filoviruses in order to enhance virion budding capacity that include members of the family of E3 ubiquitin ligase and the endosomal sorting complexes required for transport (ESCRT) pathway, while others such as tetherin inhibit viral egress. An understanding of these molecular interactions that modulate viral particle egress provides an important opportunity to identify new targets for the development of antivirals to prevent and treat filovirus infections.
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Affiliation(s)
- Tamsin B Gordon
- Health Security Program, Life Sciences Discipline, Burnet Institute, Melbourne, VIC 3004, Australia.
- Department of Microbiology, Monash University, Clayton, VIC 3168, Australia.
| | - Joshua A Hayward
- Health Security Program, Life Sciences Discipline, Burnet Institute, Melbourne, VIC 3004, Australia.
- Department of Microbiology, Monash University, Clayton, VIC 3168, Australia.
| | - Glenn A Marsh
- Department of Microbiology, Monash University, Clayton, VIC 3168, Australia.
- CSIRO Australian Animal Health Laboratory, Health and Biosecurity Business Unit, Geelong, VIC 3220, Australia.
| | - Michelle L Baker
- CSIRO Australian Animal Health Laboratory, Health and Biosecurity Business Unit, Geelong, VIC 3220, Australia.
| | - Gilda Tachedjian
- Health Security Program, Life Sciences Discipline, Burnet Institute, Melbourne, VIC 3004, Australia.
- Department of Microbiology, Monash University, Clayton, VIC 3168, Australia.
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute for Infection and Immunity, Melbourne VIC 3010, Australia.
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, VIC 3000, Australia.
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48
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Brandt J, Wendt L, Hoenen T. Structure and functions of the Ebola virus matrix protein VP40. Future Virol 2019. [DOI: 10.2217/fvl-2018-0162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The matrix protein VP40 of the highly pathogenic Ebola virus (EBOV), a member of the filovirus family, is the most abundant protein in EBOV virions. During the viral life cycle it mediates assembly and budding from the host cell, and is responsible for the characteristic filamentous shape of EBOV particles. In addition to this classical function as a matrix protein, VP40 was also shown to have a regulatory function in viral transcription. To enable these distinct functions, VP40 can adopt different oligomeric states, in particular, dimers, hexamers and ring-like octameric RNA-binding structures. This review describes the properties and functions of the EBOV matrix protein VP40 and how these different conformations of VP40 contribute to its diverse functions.
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Affiliation(s)
- Janine Brandt
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, 17493 Greifswald – Insel Riems, Germany
| | - Lisa Wendt
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, 17493 Greifswald – Insel Riems, Germany
| | - Thomas Hoenen
- Institute for Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, 17493 Greifswald – Insel Riems, Germany
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49
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Pleet ML, Erickson J, DeMarino C, Barclay RA, Cowen M, Lepene B, Liang J, Kuhn JH, Prugar L, Stonier SW, Dye JM, Zhou W, Liotta LA, Aman MJ, Kashanchi F. Ebola Virus VP40 Modulates Cell Cycle and Biogenesis of Extracellular Vesicles. J Infect Dis 2018; 218:S365-S387. [PMID: 30169850 PMCID: PMC6249571 DOI: 10.1093/infdis/jiy472] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background Ebola virus (EBOV) mainly targets myeloid cells; however, extensive death of T cells is often observed in lethal infections. We have previously shown that EBOV VP40 in exosomes causes recipient immune cell death. Methods Using VP40-producing clones, we analyzed donor cell cycle, extracellular vesicle (EV) biogenesis, and recipient immune cell death. Transcription of cyclin D1 and nuclear localization of VP40 were examined via kinase and chromatin immunoprecipitation assays. Extracellular vesicle contents were characterized by mass spectrometry, cytokine array, and western blot. Biosafety level-4 facilities were used for wild-type Ebola virus infection studies. Results VP40 EVs induced apoptosis in recipient T cells and monocytes. VP40 clones were accelerated in growth due to cyclin D1 upregulation, and nuclear VP40 was found bound to the cyclin D1 promoter. Accelerated cell cycling was related to EV biogenesis, resulting in fewer but larger EVs. VP40 EV contents were enriched in ribonucleic acid-binding proteins and cytokines (interleukin-15, transforming growth factor-β1, and interferon-γ). Finally, EBOV-infected cell and animal EVs contained VP40, nucleoprotein, and glycoprotein. Conclusions Nuclear VP40 upregulates cyclin D1 levels, resulting in dysregulated cell cycle and EV biogenesis. Packaging of cytokines and EBOV proteins into EVs from infected cells may be responsible for the decimation of immune cells during EBOV pathogenesis.
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Affiliation(s)
- Michelle L Pleet
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, Virginia
| | - James Erickson
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, Virginia
| | - Catherine DeMarino
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, Virginia
| | - Robert A Barclay
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, Virginia
| | - Maria Cowen
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, Virginia
| | | | - Janie Liang
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland
| | - Laura Prugar
- Virology Division, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland
| | - Spencer W Stonier
- Virology Division, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland
| | - John M Dye
- Virology Division, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland
| | - Weidong Zhou
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia
| | - Lance A Liotta
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia
| | - M Javad Aman
- Integrated BioTherapeutics, Inc., Gaithersburg, Maryland
| | - Fatah Kashanchi
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, Virginia
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50
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Generation of therapeutic antisera for emerging viral infections. NPJ Vaccines 2018; 3:42. [PMID: 30323953 PMCID: PMC6173733 DOI: 10.1038/s41541-018-0082-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 07/10/2018] [Accepted: 08/10/2018] [Indexed: 01/05/2023] Open
Abstract
The recent Ebola virus outbreak has highlighted the therapeutic potential of antisera and renewed interest in this treatment approach. While human convalescent sera may not be readily available in the early stages of an outbreak, antisera of animal origin can be produced in a short time frame. Here, we compared adjuvanted virus-like particles (VLP) with recombinant modified vaccinia virus Ankara and vesicular stomatitis virus (VSV), both expressing the Ebola virus antigens. The neutralizing antibody titers of rabbits immunized with adjuvanted VLPs were similar to those immunized with the replication-competent VSV, indicating that presentation of the antigen in its native conformation rather than de novo antigen expression is essential for production of functional antibodies. This approach also yielded high-titer antisera against Nipah virus glycoproteins, illustrating that it is transferable to other virus families. Multiple-step immunoglobulin G purification using a two-step 20–40% ammonium sulfate precipitation followed by protein A affinity chromatography resulted in 90% recovery of functionality and sustained in vivo stability. Adjuvanted VLP-based immunization strategies are thus a promising approach for the rapid generation of therapeutic antisera against emerging infections. Passive immunity through the transfer of anti-serum represents the earliest clinical application of antibodies and is still widely used to this day in the form of anti-venoms. Veronika von Messling and colleagues at the Paul Ehrlich Institute investigate the potential of generating neutralizing anti-serum to the emerging viruses Ebola and Nipah. The authors compare different vaccination platforms in mice and rabbits and find that following multiple vaccine challenges, neutralizing antibody titers equivalent to that seen in convalescent patients could be obtained. Purification of the IgG fraction and processing into F(ab’)2 fragments has the potential to significantly reduce xeno-responses yet the authors find that neutralizing capacity is largely retained albeit at the cost of a shorter in vivo half-life. These findings offer the hope of rapidly generating large quantities of neutralizing anti-serum that could be used in a viral outbreak scenario.
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