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Singha S, Nath N, Sarma V, Barman K, Sharma GC, Saikia L, Baruah S. Identification of Immunodominant Epitopes of Dengue Virus 2 Envelope and NS1 Proteins: Evaluating the Diagnostic Potential of a Synthetic Peptide. Mol Diagn Ther 2024; 28:633-643. [PMID: 38980575 DOI: 10.1007/s40291-024-00728-8] [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] [Accepted: 06/23/2024] [Indexed: 07/10/2024]
Abstract
BACKGROUND AND OBJECTIVE Dengue is a major infectious disease with potential for outbreaks and epidemics. A specific and sensitive diagnosis is a prerequisite for clinical management of the disease. We designed our study to identify epitopes on the Dengue virus (DENV) envelope (E) and non-structural protein 1 (NS1) with potential for diagnosis. METHODS Serology and immunoinformatic approaches were employed. We collected DENV-positive, DENV-negative and Japanese encephalitis virus-positive samples from collaborating hospitals in 2019 and 2022-2023. Seropositive peptides in 15-18 mer peptide arrays of E and NS1 proteins of DENV2 were determined by an indirect enzyme-linked immunosorbent assay. B-cell linear and conformational epitopes were predicted using BepiPred2.0 and ElliPro, respectively. A consensus recombinant peptide was designed, synthesised and evaluated for its diagnostic potential using patient sera. RESULTS Eight peptides of E protein and six peptides of NS1 protein were identified to be the most frequently recognised by Dengue-positive patients. These peptide sequences were compared with B-cell epitope regions and found to be overlapped with predicted B-cell linear and conformational epitopes. EP11 and NSP15 showed a 100% amino acid sequence overlap with B-cell epitopes. EP1 and NSP15 had 14 whereas EP28, EP31, EP60 16, NSP12 and NSP32 had more than 15 interacting interface residues with a neutralising antibody, suggesting a strength of interaction. Interestingly, potential epitopes identified were localised on the surface of proteins as visualised by PyMOL. Validation with a recombined synthetic peptide yielded 92.3% sensitivity and 91.42% specificity. CONCLUSIONS Immunodominant regions identified by serology and computationally predicted epitopes overlapped, thereby showing the robustness of the methodology and the peptide designed for diagnosis.
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Affiliation(s)
- Sushmita Singha
- Department of Molecular Biology and Biotechnology, Tezpur University, Napaam, Sonitpur Assam, 784028, India
| | - Neena Nath
- Gauhati Medical College and Hospital, Bhangagarh, Guwahati, Assam, India
| | - Vaishali Sarma
- Gauhati Medical College and Hospital, Bhangagarh, Guwahati, Assam, India
| | - Kangkana Barman
- Department of Molecular Biology and Biotechnology, Tezpur University, Napaam, Sonitpur Assam, 784028, India
| | - Gurumayum Chourajit Sharma
- Department of Molecular Biology and Biotechnology, Tezpur University, Napaam, Sonitpur Assam, 784028, India
| | - Lahari Saikia
- Gauhati Medical College and Hospital, Bhangagarh, Guwahati, Assam, India
| | - Shashi Baruah
- Department of Molecular Biology and Biotechnology, Tezpur University, Napaam, Sonitpur Assam, 784028, India.
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Roy A, Paul I, Paul T, Hazarika K, Dihidar A, Ray S. An in-silico receptor-pharmacophore based multistep molecular docking and simulation study to evaluate the inhibitory potentials against NS1 of DENV-2. J Biomol Struct Dyn 2024; 42:6136-6164. [PMID: 37517062 DOI: 10.1080/07391102.2023.2239925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Accepted: 06/25/2023] [Indexed: 08/01/2023]
Abstract
DENV-2 strain is the most fatal and infectious of the five dengue virus serotypes. The non-structural protein NS1 encoded by its genome is the most significant protein required for viral pathogenesis and replication inside the host body. Thus, targeting the NS1 protein and designing an inhibitor to limit its stability and secretion is a propitious attempt in our fight against dengue. Four novel inhibitors are designed to target the conserved cysteine residues (C55, C313, C316, and C329) and glycosylation sites (N130 and N207) of the NS1 protein in an attempt to halt the spread of the dengue infection in the host body altogether. Numerous computer-aided drug designing techniques including molecular docking, molecular dynamics simulation, virtual screening, principal component analysis, and dynamic cross-correlation matrix were employed to determine the structural and functional activity of the NS1-inhibitor complexes. From our analysis, it was evident that the extent of structural and atomic level fluctuations of the ligand-bound protein exhibited a declining trend in contrast to unbound protein which was prominently noticeable through the RMSD, RMSF, Rg, and SASA graphs. The ADMET analysis of the four ligands revealed a promising pharmacokinetics and pharmacodynamic profile, along with good bioavailability and toxicity properties. The proposed drugs when bound to the targeted cavities resulted in stable conformations in comparison to their unbound state, implying they have good affinity promising effective drug action. Thus, they can be tested in vitro and used as potential anti-dengue drugs.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Alankar Roy
- Amity Institute of Biotechnology, Amity University, Kolkata, India
| | - Ishani Paul
- Amity Institute of Biotechnology, Amity University, Kolkata, India
| | - Tanwi Paul
- Amity Institute of Biotechnology, Amity University, Kolkata, India
| | | | - Aritrika Dihidar
- Amity Institute of Biotechnology, Amity University, Kolkata, India
| | - Sujay Ray
- Amity Institute of Biotechnology, Amity University, Kolkata, India
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Perera DR, Ranadeva ND, Sirisena K, Wijesinghe KJ. Roles of NS1 Protein in Flavivirus Pathogenesis. ACS Infect Dis 2024; 10:20-56. [PMID: 38110348 DOI: 10.1021/acsinfecdis.3c00566] [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] [Indexed: 12/20/2023]
Abstract
Flaviviruses such as dengue, Zika, and West Nile viruses are highly concerning pathogens that pose significant risks to public health. The NS1 protein is conserved among flaviviruses and is synthesized as a part of the flavivirus polyprotein. It plays a critical role in viral replication, disease progression, and immune evasion. Post-translational modifications influence NS1's stability, secretion, antigenicity, and interactions with host factors. NS1 protein forms extensive interactions with host cellular proteins allowing it to affect vital processes such as RNA processing, gene expression regulation, and cellular homeostasis, which in turn influence viral replication, disease pathogenesis, and immune responses. NS1 acts as an immune evasion factor by delaying complement-dependent lysis of infected cells and contributes to disease pathogenesis by inducing endothelial cell damage and vascular leakage and triggering autoimmune responses. Anti-NS1 antibodies have been shown to cross-react with host endothelial cells and platelets, causing autoimmune destruction that is hypothesized to contribute to disease pathogenesis. However, in contrast, immunization of animal models with the NS1 protein confers protection against lethal challenges from flaviviruses such as dengue and Zika viruses. Understanding the multifaceted roles of NS1 in flavivirus pathogenesis is crucial for effective disease management and control. Therefore, further research into NS1 biology, including its host protein interactions and additional roles in disease pathology, is imperative for the development of strategies and therapeutics to combat flavivirus infections successfully. This Review provides an in-depth exploration of the current available knowledge on the multifaceted roles of the NS1 protein in the pathogenesis of flaviviruses.
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Affiliation(s)
- Dayangi R Perera
- Department of Chemistry, Faculty of Science, University of Colombo, Sri Lanka 00300
| | - Nadeeka D Ranadeva
- Department of Biomedical Science, Faculty of Health Sciences, KIU Campus Sri Lanka 10120
| | - Kavish Sirisena
- Department of Chemistry, Faculty of Science, University of Colombo, Sri Lanka 00300
- Section of Genetics, Institute for Research and Development in Health and Social Care, Sri Lanka 10120
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4
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Zhang S, He Y, Wu Z, Wang M, Jia R, Zhu D, Liu M, Zhao X, Yang Q, Wu Y, Zhang S, Huang J, Ou X, Gao Q, Sun D, Zhang L, Yu Y, Chen S, Cheng A. Secretory pathways and multiple functions of nonstructural protein 1 in flavivirus infection. Front Immunol 2023; 14:1205002. [PMID: 37520540 PMCID: PMC10372224 DOI: 10.3389/fimmu.2023.1205002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 06/27/2023] [Indexed: 08/01/2023] Open
Abstract
The genus Flavivirus contains a wide variety of viruses that cause severe disease in humans, including dengue virus, yellow fever virus, Zika virus, West Nile virus, Japanese encephalitis virus and tick-borne encephalitis virus. Nonstructural protein 1 (NS1) is a glycoprotein that encodes a 352-amino-acid polypeptide and has a molecular weight of 46-55 kDa depending on its glycosylation status. NS1 is highly conserved among multiple flaviviruses and occurs in distinct forms, including a dimeric form within the endoplasmic reticulum, a cell-associated form on the plasma membrane, or a secreted hexameric form (sNS1) trafficked to the extracellular matrix. Intracellular dimeric NS1 interacts with other NSs to participate in viral replication and virion maturation, while extracellular sNS1 plays a critical role in immune evasion, flavivirus pathogenesis and interactions with natural vectors. In this review, we provide an overview of recent research progress on flavivirus NS1, including research on the structural details, the secretory pathways in mammalian and mosquito cells and the multiple functions in viral replication, immune evasion, pathogenesis and interaction with natural hosts, drawing together the previous data to determine the properties of this protein.
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Affiliation(s)
- Senzhao Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Yu He
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Zhen Wu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Dekang Zhu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Mafeng Liu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Xinxin Zhao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Qiao Yang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Ying Wu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Shaqiu Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Juan Huang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Xumin Ou
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Qun Gao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Di Sun
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Ling Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yanling Yu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Shun Chen
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
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5
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Tan BEK, Beard MR, Eyre NS. Identification of Key Residues in Dengue Virus NS1 Protein That Are Essential for Its Secretion. Viruses 2023; 15:v15051102. [PMID: 37243188 DOI: 10.3390/v15051102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/21/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
Dengue virus (DENV) non-structural protein 1 (NS1) is involved in multiple aspects of the DENV lifecycle. Importantly, it is secreted from infected cells as a hexameric lipoparticle that mediates vascular damage that is a hallmark of severe dengue. Although the secretion of NS1 is known to be important in DENV pathogenesis, the exact molecular features of NS1 that are required for its secretion from cells are not fully understood. In this study, we employed random point mutagenesis in the context of an NS1 expression vector encoding a C-terminal HiBiT luminescent peptide tag to identify residues within NS1 that are essential for its secretion. Using this approach, we identified 10 point mutations that corresponded with impaired NS1 secretion, with in silico analyses indicating that the majority of these mutations are located within the β-ladder domain. Additional studies on two of these mutants, V220D and A248V, revealed that they prevented viral RNA replication, while studies using a DENV NS1-NS5 viral polyprotein expression system demonstrated that these mutations resulted in a more reticular NS1 localisation pattern and failure to detect mature NS1 at its predicted molecular weight by Western blotting using a conformation-specific monoclonal antibody. Together, these studies demonstrate that the combination of a luminescent peptide tagged NS1 expression system with random point mutagenesis enables rapid identification of mutations that alter NS1 secretion. Two such mutations identified via this approach revealed residues that are essential for correct NS1 processing or maturation and viral RNA replication.
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Affiliation(s)
- Brandon E K Tan
- Research Centre of Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - Michael R Beard
- Research Centre of Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - Nicholas S Eyre
- College of Medicine and Public Health (CMPH), Flinders University, Bedford Park, SA 5042, Australia
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6
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Sharma A, Krishna S, Sowdhamini R. Bioinformatics Analysis of Mutations Sheds Light on the Evolution of Dengue NS1 Protein With Implications in the Identification of Potential Functional and Druggable Sites. Mol Biol Evol 2023; 40:7043264. [PMID: 36795614 PMCID: PMC9989740 DOI: 10.1093/molbev/msad033] [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: 08/30/2022] [Revised: 12/26/2022] [Accepted: 01/30/2023] [Indexed: 02/17/2023] Open
Abstract
Non-structural protein (NS1) is a 350 amino acid long conserved protein in the dengue virus. Conservation of NS1 is expected due to its importance in dengue pathogenesis. The protein is known to exist in dimeric and hexameric states. The dimeric state is involved in its interaction with host proteins and viral replication, and the hexameric state is involved in viral invasion. In this work, we performed extensive structure and sequence analysis of NS1 protein, and uncovered the role of NS1 quaternary states in its evolution. A three-dimensional modeling of unresolved loop regions in NS1 structure is performed. "Conserved" and "Variable" regions within NS1 protein were identified from sequences obtained from patient samples and the role of compensatory mutations in selecting destabilizing mutations were identified. Molecular dynamics (MD) simulations were performed to extensively study the effect of a few mutations on NS1 structure stability and compensatory mutations. Virtual saturation mutagenesis, predicting the effect of every individual amino acid substitution on NS1 stability sequentially, revealed virtual-conserved and variable sites. The increase in number of observed and virtual-conserved regions across NS1 quaternary states suggest the role of higher order structure formation in its evolutionary conservation. Our sequence and structure analysis could enable in identifying possible protein-protein interfaces and druggable sites. Virtual screening of nearly 10,000 small molecules, including FDA-approved drugs, permitted us to recognize six drug-like molecules targeting the dimeric sites. These molecules could be promising due to their stable interactions with NS1 throughout the simulation.
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Affiliation(s)
- Abhishek Sharma
- National Centre for Biological Science, TIFR, Bangalore, India
| | - Sudhir Krishna
- National Centre for Biological Science, TIFR, Bangalore, India.,Department of School of Interdisciplinary Life Sciences, Indian Institute of Technology Goa, Farmagudi, Pond-403401, Goa, India
| | - Ramanathan Sowdhamini
- National Centre for Biological Science, TIFR, Bangalore, India.,Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India.,Computational Biology, Institute of Bioinformatics and Applied Biotechnology, Bangalore, India
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7
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Flavivirus-Host Interaction Landscape Visualized through Genome-Wide CRISPR Screens. Viruses 2022; 14:v14102164. [PMID: 36298718 PMCID: PMC9609550 DOI: 10.3390/v14102164] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 09/25/2022] [Accepted: 09/25/2022] [Indexed: 11/14/2022] Open
Abstract
Flaviviruses comprise several important human pathogens which cause significant morbidity and mortality worldwide. Like any other virus, they are obligate intracellular parasites. Therefore, studying the host cellular factors that promote or restrict their replication and pathogenesis becomes vital. Since inhibiting the host dependency factors or activating the host restriction factors can suppress the viral replication and propagation in the cell, identifying them reveals potential targets for antiviral therapeutics. Clustered regularly interspaced short palindromic repeats (CRISPR) technology has provided an effective means of producing customizable genetic modifications and performing forward genetic screens in a broad spectrum of cell types and organisms. The ease, rapidity, and high reproducibility of CRISPR technology have made it an excellent tool for carrying out genome-wide screens to identify and characterize viral host dependency factors systematically. Here, we review the insights from various Genome-wide CRISPR screens that have advanced our understanding of Flavivirus-Host interactions.
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8
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Kumar S, Verma A, Yadav P, Dubey SK, Azhar EI, Maitra SS, Dwivedi VD. Molecular pathogenesis of Japanese encephalitis and possible therapeutic strategies. Arch Virol 2022; 167:1739-1762. [PMID: 35654913 PMCID: PMC9162114 DOI: 10.1007/s00705-022-05481-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 03/10/2022] [Indexed: 12/26/2022]
Abstract
Japanese encephalitis virus (JEV), a single-stranded, enveloped RNA virus, is a health concern across Asian countries, associated with severe neurological disorders, especially in children. Primarily, pigs, bats, and birds are the natural hosts for JEV, but humans are infected incidentally. JEV requires a few host proteins for its entry and replication inside the mammalian host cell. The endoplasmic reticulum (ER) plays a significant role in JEV genome replication and assembly. During this process, the ER undergoes stress due to its remodelling and accumulation of viral particles and unfolded proteins, leading to an unfolded protein response (UPR). Here, we review the overall strategy used by JEV to infect the host cell and various cytopathic effects caused by JEV infection. We also highlight the role of JEV structural proteins (SPs) and non-structural proteins (NSPs) at various stages of the JEV life cycle that are involved in up- and downregulation of different host proteins and are potentially relevant for developing efficient therapeutic drugs.
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Affiliation(s)
- Sanjay Kumar
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067 India
- Center for Bioinformatics, Computational and Systems Biology, Pathfinder Research and Training Foundation, Greater Noida, India
| | - Akanksha Verma
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Pardeep Yadav
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, Uttar Pradesh 201310 India
- Center for Bioinformatics, Computational and Systems Biology, Pathfinder Research and Training Foundation, Greater Noida, India
| | | | - Esam Ibraheem Azhar
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, 21589 Saudi Arabia
| | - S. S. Maitra
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Vivek Dhar Dwivedi
- Center for Bioinformatics, Computational and Systems Biology, Pathfinder Research and Training Foundation, Greater Noida, India
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Lubna S, Chinta S, Burra P, Vedantham K, Ray S, Bandyopadhyay D. New substitutions on NS1 protein from influenza A (H1N1) virus: Bioinformatics analyses of Indian strains isolated from 2009 to 2020. Health Sci Rep 2022; 5:e626. [PMID: 35509388 PMCID: PMC9059196 DOI: 10.1002/hsr2.626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 03/21/2022] [Accepted: 03/24/2022] [Indexed: 11/06/2022] Open
Affiliation(s)
- Syeda Lubna
- Birla Institute of Technology and Science, Pilani, Hyderabad Campus Hyderabad Telangana India
| | - Suma Chinta
- Birla Institute of Technology and Science, Pilani, Hyderabad Campus Hyderabad Telangana India
| | - Prakruthi Burra
- Birla Institute of Technology and Science, Pilani, Hyderabad Campus Hyderabad Telangana India
| | - Kiranmayi Vedantham
- Birla Institute of Technology and Science, Pilani, Hyderabad Campus Hyderabad Telangana India
| | | | - Debashree Bandyopadhyay
- Birla Institute of Technology and Science, Pilani, Hyderabad Campus Hyderabad Telangana India
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10
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Feng T, Zhang J, Chen Z, Pan W, Chen Z, Yan Y, Dai J. Glycosylation of viral proteins: Implication in virus-host interaction and virulence. Virulence 2022; 13:670-683. [PMID: 35436420 PMCID: PMC9037552 DOI: 10.1080/21505594.2022.2060464] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Glycans are among the most important cell molecular components. However, given their structural diversity, their functions have not been fully explored. Glycosylation is a vital post-translational modification for various proteins. Many bacteria and viruses rely on N-linked and O-linked glycosylation to perform critical biological functions. The diverse functions of glycosylation on viral proteins during viral infections, including Dengue, Zika, influenza, and human immunodeficiency viruses as well as coronaviruses have been reported. N-linked glycosylation is the most common form of protein modification, and it modulates folding, transportation and receptor binding. Compared to N-linked glycosylation, the functions of O-linked viral protein glycosylation have not been comprehensively evaluated. In this review, we summarize findings on viral protein glycosylation, with particular attention to studies on N-linked glycosylation in viral life cycles. This review informs the development of virus-specific vaccines or inhibitors.
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Affiliation(s)
- Tingting Feng
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Suzhou, China
| | - Jinyu Zhang
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Suzhou, China
| | - Zhiqian Chen
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Suzhou, China
| | - Wen Pan
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Suzhou, China
| | - Zhengrong Chen
- Department of Respiratory Medicine, Children's Hospital of Soochow University, Soochow University, Suzhou, China
| | - Yongdong Yan
- Department of Respiratory Medicine, Children's Hospital of Soochow University, Soochow University, Suzhou, China
| | - Jianfeng Dai
- Jiangsu Key Laboratory of Infection and Immunity, Institute of Biology and Medical Sciences, Soochow University, Suzhou, China
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11
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Rossi ÁD, Higa LM, Herlinger AL, Ribeiro-Alves M, de Menezes MT, Giannini ALM, Cardoso CC, Da Poian AT, Tanuri A, Aguiar RS. Differential Expression of Human MicroRNAs During Dengue Virus Infection in THP-1 Monocytes. Front Cell Infect Microbiol 2021; 11:714088. [PMID: 34568093 PMCID: PMC8455953 DOI: 10.3389/fcimb.2021.714088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 08/25/2021] [Indexed: 12/31/2022] Open
Abstract
Dengue virus (DENV) is the most widespread arbovirus, responsible for a wide range of clinical manifestations, varying from self-limited illness to severe hemorrhagic fever. Dengue severity is associated with host intense proinflammatory response and monocytes have been considered one of the key cell types involved in the early steps of DENV infection and immunopathogenesis. To better understand cellular mechanisms involved in monocyte infection by DENV, we analyzed the expression levels of 754 human microRNAs in DENV-infected THP-1 cells, a human monocytic cell line. Eleven human microRNAs showed differential expression after DENV infection and gene ontology and enrichment analysis revealed biological processes potentially affected by these molecules. Five downregulated microRNAs were significantly linked to cellular response to stress, four to cell death/apoptosis, two to innate immune responses and one upregulated to vesicle mediated, TGF-β signaling, phosphatidylinositol mediated signaling, lipid metabolism process and blood coagulation.
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Affiliation(s)
- Átila Duque Rossi
- Laboratório de Virologia Molecular, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luiza Mendonça Higa
- Laboratório de Virologia Molecular, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Laboratório de Bioquímica de Vírus, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alice Laschuk Herlinger
- Laboratório de Virologia Molecular, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcelo Ribeiro-Alves
- Laboratório de Pesquisa Clínica em DST/AIDS, Instituto Nacional de Infectologia Evandro Chagas, FIOCRUZ, Rio de Janeiro, Brazil
| | - Mariane Talon de Menezes
- Laboratório de Virologia Molecular, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Lucia Moraes Giannini
- Laboratório de Genômica Funcional e Transdução de Sinal, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Cynthia Chester Cardoso
- Laboratório de Virologia Molecular, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Andrea T Da Poian
- Laboratório de Bioquímica de Vírus, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Amilcar Tanuri
- Laboratório de Virologia Molecular, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Renato Santana Aguiar
- Laboratório de Virologia Molecular, Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Laboratório de Biologia Integrativa, Departamento de Genética, Ecologia e Evolução, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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12
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N130, N175 and N207 are N-linked glycosylation sites of duck Tembusu virus NS1 that are important for viral multiplication, viremia and virulence in ducklings. Vet Microbiol 2021; 261:109215. [PMID: 34455356 DOI: 10.1016/j.vetmic.2021.109215] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 08/22/2021] [Indexed: 02/04/2023]
Abstract
Duck Tembusu virus (DTMUV) is an emerging mosquito-borne flavivirus that has caused acute egg-drop syndrome in egg-laying ducks. DTMUV nonstructural protein 1 (NS1) contains three potential predicted N-linked glycosylation sites at residues 130, 175 and 207. In this study, we found that mutations at these sites affect the molecular weight of recombinant NS1, as assessed by western blot assays; however, the mutations do not affect their subcellular localization in the cytoplasm, as assessed by colocalization assays. Four recombinant viruses substituting the asparagine (N) residues at N130, N175, N207 or N130/N175/N207 of NS1 with alanine (A) residues were generated using rDTMUV-i, an infectious cDNA clone of the DTMUV CQW1 strain. Deglycosylation assays of the mutant virus NS1 were performed using endoglycosidases Endo H or PNGase F treatment in both mammalian and avian cells. The NS1-WT, NS1-N130A, NS1-N175A and NS1-N207A showed a shift in migration to 37 kDa after digestion with both endoglycosidases, which further confirmed that N130, N175 and N207 were the glycosylation sites of DTMUV NS1. Compared to the parental rDTMUV, the single mutants impaired viral multiplication in vitro, while the nonglycosylated virus rDTMUV-NS1-N130A/N175A/N207A showed a 5-fold to 178-fold decrease in viral titers and smaller plaque sizes. Notably, all mutant viruses were still highly virulent to duck embryos, but the embryos inoculated with rDTMUV-NS1-N130A/N175A/N207A started to die on the fourth day, which exhibited a prolonged time to death compared to that of rDTMUV. Moreover, rDTMUV-NS1-N130A/N175A/N207A was attenuated in vivo, showing no mortality and producing significantly lower viral titers in heart, spleen, kidney, brain and thymus as well as 2-fold to 3-fold lower viremia at 3 and 5 days post infection. Overall, our results indicated that N130, N175 and N207 are N-linked glycosylation sites of DTMUV NS1, which play crucial roles in viral multiplication, viremia and virulence in vitro and in vivo.
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13
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Carpio KL, Barrett ADT. Flavivirus NS1 and Its Potential in Vaccine Development. Vaccines (Basel) 2021; 9:622. [PMID: 34207516 PMCID: PMC8229460 DOI: 10.3390/vaccines9060622] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 12/19/2022] Open
Abstract
The Flavivirus genus contains many important human pathogens, including dengue, Japanese encephalitis (JE), tick-borne encephalitis (TBE), West Nile (WN), yellow fever (YF) and Zika (ZIK) viruses. While there are effective vaccines for a few flavivirus diseases (JE, TBE and YF), the majority do not have vaccines, including WN and ZIK. The flavivirus nonstructural 1 (NS1) protein has an unusual structure-function because it is glycosylated and forms different structures to facilitate different roles intracellularly and extracellularly, including roles in the replication complex, assisting in virus assembly, and complement antagonism. It also plays a role in protective immunity through antibody-mediated cellular cytotoxicity, and anti-NS1 antibodies elicit passive protection in animal models against a virus challenge. Historically, NS1 has been used as a diagnostic marker for the flavivirus infection due to its complement fixing properties and specificity. Its role in disease pathogenesis, and the strong humoral immune response resulting from infection, makes NS1 an excellent target for inclusion in candidate flavivirus vaccines.
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Affiliation(s)
- Kassandra L. Carpio
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA;
| | - Alan D. T. Barrett
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA
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14
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Burton TD, Eyre NS. Applications of Deep Mutational Scanning in Virology. Viruses 2021; 13:1020. [PMID: 34071591 PMCID: PMC8227372 DOI: 10.3390/v13061020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/26/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022] Open
Abstract
Several recently developed high-throughput techniques have changed the field of molecular virology. For example, proteomics studies reveal complete interactomes of a viral protein, genome-wide CRISPR knockout and activation screens probe the importance of every single human gene in aiding or fighting a virus, and ChIP-seq experiments reveal genome-wide epigenetic changes in response to infection. Deep mutational scanning is a relatively novel form of protein science which allows the in-depth functional analysis of every nucleotide within a viral gene or genome, revealing regions of importance, flexibility, and mutational potential. In this review, we discuss the application of this technique to RNA viruses including members of the Flaviviridae family, Influenza A Virus and Severe Acute Respiratory Syndrome Coronavirus 2. We also briefly discuss the reverse genetics systems which allow for analysis of viral replication cycles, next-generation sequencing technologies and the bioinformatics tools that facilitate this research.
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Affiliation(s)
| | - Nicholas S. Eyre
- College of Medicine and Public Health, Flinders University, Bedford Park, SA 5042, Australia;
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15
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Lee PX, Ting DHR, Boey CPH, Tan ETX, Chia JZH, Idris F, Oo Y, Ong LC, Chua YL, Hapuarachchi C, Ng LC, Alonso S. Relative contribution of nonstructural protein 1 in dengue pathogenesis. J Exp Med 2021; 217:151891. [PMID: 32584412 PMCID: PMC7478733 DOI: 10.1084/jem.20191548] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 04/10/2020] [Accepted: 05/13/2020] [Indexed: 12/16/2022] Open
Abstract
Dengue is a major public health concern in the tropical and subtropical world, with no effective treatment. The controversial live attenuated virus vaccine Dengvaxia has boosted the pursuit of subunit vaccine approaches, and nonstructural protein 1 (NS1) has recently emerged as a promising candidate. However, we found that NS1 immunization or passive transfer of NS1 antibodies failed to confer protection in symptomatic dengue mouse models using two non–mouse-adapted DENV2 strains that are highly virulent. Exogenous administration of purified NS1 also failed to worsen in vivo vascular leakage in sublethally infected mice. Neither method of NS1 immune neutralization changed the disease outcome of a chimeric strain expressing a vascular leak-potent NS1. Instead, virus chimerization involving the prME structural region indicated that these proteins play a critical role in driving in vivo fitness and virulence of the virus, through induction of key proinflammatory cytokines. This work highlights that the pathogenic role of NS1 is DENV strain dependent, which warrants reevaluation of NS1 as a universal dengue vaccine candidate.
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Affiliation(s)
- Pei Xuan Lee
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Donald Heng Rong Ting
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Clement Peng Hee Boey
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Eunice Tze Xin Tan
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Janice Zuo Hui Chia
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Fakhriedzwan Idris
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Yukei Oo
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Li Ching Ong
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
| | - Yen Leong Chua
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | | | - Lee Ching Ng
- Environmental Health Institute at National Environment Agency, Singapore
| | - Sylvie Alonso
- Infectious Disease Programme and Department of Microbiology & Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore
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16
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Barbachano-Guerrero A, Endy TP, King CA. Dengue virus non-structural protein 1 activates the p38 MAPK pathway to decrease barrier integrity in primary human endothelial cells. J Gen Virol 2020; 101:484-496. [PMID: 32141809 DOI: 10.1099/jgv.0.001401] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Dengue virus (DENV) causes an estimated 390 million infections worldwide annually, with severe forms of disease marked by vascular leakage. Endothelial cells (EC) are directly responsible for vascular homeostasis and are highly responsive to circulating mediators but are not commonly infected. DENV encodes seven non-structural (NS) proteins; with only one of those, NS1, secreted from infected cells and accumulating in the blood of patients. NS1 has been implicated in the pathogenesis of vascular permeability, but the mechanism is not completely understood. Here we used primary endothelial cells and an array of in vitro approaches to study the effect of NS1 in disease-relevant human ECs. Confocal microscopy demonstrated rapid NS1 internalization by ECs into endosomes with accumulation over time. Transcriptomic and pathway analysis showed significant changes in functions associated with EC homeostasis and vascular permeability. Functional significance of this activation was assessed by trans-endothelial electrical resistance and showed that NS1 induced rapid and transient loss in EC barrier function within 3 h post-treatment. To understand the molecular mechanism by which NS1 induced EC activation, we evaluated the stress-sensing p38 MAPK pathway known to be directly involved in EC permeability and inflammation. WB analysis of NS1-stimulated ECs showed clear activation of p38 MAPK and downstream effectors MAPKAPK-2 and HSP27 with chemical inhibition of the p38 MAP kinase pathway restoring barrier function. Our results suggest that DENV NS1 may be involved in the pathogenesis of severe dengue by activating the p38 MAPK in ECs, promoting increased permeability that characterizes severe disease.
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Affiliation(s)
| | - Timothy P Endy
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse NY, USA
| | - Christine A King
- Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse NY, USA
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17
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Faheem M, Barbosa Lima JC, Jamal SB, Silva PA, Barbosa JARG. An insight into dengue virus proteins as potential drug/vaccine targets. Future Virol 2019. [DOI: 10.2217/fvl-2019-0107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dengue virus (DENV) is an arbovirus that belongs to family flaviviridae. Its genome is composed of a single stranded RNA molecule that encodes a single polyprotein. The polyprotein is processed by viral and cellular proteases to generate ten viral proteins. There are four antigenically distinct serotypes of DENV (DENV1, DENV2, DENV3 and DENV4), which are genetically related. Although protein variability is a major problem in dengue treatment, the functional and structural studies of individual proteins are equally important in treatment development. The data accumulated on dengue proteins are significant to provide detailed understanding of viral infection, replication, host-immune evasion and pathogenesis. In this review, we summarized the detailed current knowledge about DENV proteins.
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Affiliation(s)
- Muhammad Faheem
- Laboratory of Biophysics, Department of Cellular Biology, University of Brasilia, Brasilia-DF 70910-900, Brazil
- Post-graduate program of Genomics Sciences & Biotechnology, Catholic University of Brasilia, Brasília-DF 70790-160, Brazil
| | - Jônatas Cunha Barbosa Lima
- Laboratory of Biophysics, Department of Cellular Biology, University of Brasilia, Brasilia-DF 70910-900, Brazil
| | - Syed Babar Jamal
- Department of Biological Sciences, National University of Medical Sciences, The Mall road, Rawalpindi, Punjab 46000, Pakistan
| | - Paula Andreia Silva
- Post-graduate program of Genomics Sciences & Biotechnology, Catholic University of Brasilia, Brasília-DF 70790-160, Brazil
| | - João Alexandre Ribeiro Gonçalves Barbosa
- Laboratory of Biophysics, Department of Cellular Biology, University of Brasilia, Brasilia-DF 70910-900, Brazil
- Post-graduate program of Genomics Sciences & Biotechnology, Catholic University of Brasilia, Brasília-DF 70790-160, Brazil
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18
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Fukuhara T, Matsuura Y. Roles of secretory glycoproteins in particle formation of Flaviviridae viruses. Microbiol Immunol 2019; 63:401-406. [PMID: 31342548 DOI: 10.1111/1348-0421.12733] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/17/2019] [Accepted: 07/18/2019] [Indexed: 12/12/2022]
Abstract
The family Flaviviridae comprises four genera, namely, Flavivirus, Pestivirus, Pegivirus, and Hepacivirus. These viruses have similar genome structures, but the genomes of Pestivirus and Flavivirus encode the secretory glycoproteins Erns and NS1, respectively. Erns plays an important role in virus particle formation and cell entry, whereas NS1 participates in the formation of replication complexes and virus particles. Conversely, apolipoproteins are known to participate in the formation of infectious particles of hepatitis C virus (HCV) and various secretory glycoproteins play a similar role in HCV particles formation, suggesting that there is no strong specificity for the function of secretory glycoproteins in infectious-particle formation. In addition, recent studies have shown that host-derived apolipoproteins and virus-derived Erns and NS1 play comparable roles in infectious-particle formation of both HCV and pestiviruses. In this review, we summarize the roles of secretory glycoproteins in the formation of Flaviviridae virus particles.
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Affiliation(s)
- Takasuke Fukuhara
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Yoshiharu Matsuura
- Department of Molecular Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
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19
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Vora J, Patel S, Athar M, Sinha S, Chhabria MT, Jha PC, Shrivastava N. Pharmacophore modeling, molecular docking and molecular dynamics simulation for screening and identifying anti-dengue phytocompounds. J Biomol Struct Dyn 2019; 38:1726-1740. [PMID: 31057055 DOI: 10.1080/07391102.2019.1615002] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Dengue is a fast spreading mosquito borne viral disease that poses a serious threat to human health. Lack of therapeutic drugs and vaccines signify that more resources need to be explored. Accumulated evidence has suggested that plants offer a vast reservoir for antiviral drug discovery which are safe for human consumption. Plant-based drug discovery is a complex and time-consuming process as plants possess rich repository of chemically diverse compounds. Various in silico methods can make this process simple and economic. We, therefore, performed pharmacophore mapping, molecular docking, molecular dynamics (MD) simulations and ADME (absorption, distribution, metabolism, excretion) prediction to screen potential candidates against dengue. In particular, combined pharmacophore mapping and molecular docking were used to prioritize the potentially active ligands from a ligand library. Biological activities of plant based ligands were predicted using 3D-QSAR pharmacophore modeling. Interaction between proteins, namely, envelope G protein, NS2B/NS3 protease, NS5 methyltransferase, NS1, NS5 polymerase and active plant-based ligands (pIC50 > 5.1) were analyzed using molecular docking. Best docked complex, namely, envelope G protein-mulberroside C, NS2B-NS3 protease-curcumin, NS5 methyltransferase-chebulic acid, NS1-mulberroside A, NS5 methyltransferase-punigluconin and NS5 methyltransferase-chebulic acid were further subjected to MD simulations study to assess the fluctuation and conformational changes during protein-ligand interaction. ADME studies were performed to assess their drug-likeness properties. Collectively, these in silico results helped to identify the potential plant-based hits against the various receptors of dengue virus which can be further validated by bioactivity-based experiments.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Jaykant Vora
- B. V. Patel Pharmaceutical Education and Research Development (PERD) Centre, Ahmedabad, India.,Department of Life science, Gujarat University, Ahmedabad, India
| | - Shivani Patel
- Department of Pharmaceutical Chemistry, L. M. College of Pharmacy, Ahmedabad, India
| | - Mohd Athar
- School of Chemical Sciences, Central University of Gujarat, Gandhinagar, India
| | - Sonam Sinha
- B. V. Patel Pharmaceutical Education and Research Development (PERD) Centre, Ahmedabad, India.,Department of Life science, Gujarat University, Ahmedabad, India
| | - Mahesh T Chhabria
- Department of Pharmaceutical Chemistry, L. M. College of Pharmacy, Ahmedabad, India
| | - Prakash C Jha
- Centre for Applied Chemistry, Central University of Gujarat, Gandhinagar, India
| | - Neeta Shrivastava
- B. V. Patel Pharmaceutical Education and Research Development (PERD) Centre, Ahmedabad, India
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20
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Dwivedi VD, Tripathi IP, Tripathi RC, Bharadwaj S, Mishra SK. Genomics, proteomics and evolution of dengue virus. Brief Funct Genomics 2018; 16:217-227. [PMID: 28073742 DOI: 10.1093/bfgp/elw040] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The genome of a pathogenic organism possesses a specific order of nucleotides that contains not only information about the synthesis and expression of proteomes, which are required for its growth and survival, but also about its evolution. Inhibition of any particular protein, which is required for the survival of that pathogenic organism, can be used as a potential therapeutic target for the development of effective drugs to treat its infections. In this review, the genomics, proteomics and evolution of dengue virus have been discussed, which will be helpful in better understanding of its origin, growth, survival and evolution, and may contribute toward development of new efficient anti-dengue drugs.
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21
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Poonsiri T, Wright GSA, Diamond MS, Turtle L, Solomon T, Antonyuk SV. Structural Study of the C-Terminal Domain of Nonstructural Protein 1 from Japanese Encephalitis Virus. J Virol 2018; 92:e01868-17. [PMID: 29343583 PMCID: PMC5972899 DOI: 10.1128/jvi.01868-17] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 01/12/2018] [Indexed: 01/01/2023] Open
Abstract
Japanese encephalitis virus (JEV) is a mosquito-transmitted flavivirus that is closely related to other emerging viral pathogens, including dengue virus (DENV), West Nile virus (WNV), and Zika virus (ZIKV). JEV infection can result in meningitis and encephalitis, which in severe cases cause permanent brain damage and death. JEV occurs predominantly in rural areas throughout Southeast Asia, the Pacific Islands, and the Far East, causing around 68,000 cases of infection worldwide each year. In this report, we present a 2.1-Å-resolution crystal structure of the C-terminal β-ladder domain of JEV nonstructural protein 1 (NS1-C). The surface charge distribution of JEV NS1-C is similar to those of WNV and ZIKV but differs from that of DENV. Analysis of the JEV NS1-C structure, with in silico molecular dynamics simulation and experimental solution small-angle X-ray scattering, indicates extensive loop flexibility on the exterior of the protein. This, together with the surface charge distribution, indicates that flexibility influences the protein-protein interactions that govern pathogenicity. These factors also affect the interaction of NS1 with the 22NS1 monoclonal antibody, which is protective against West Nile virus infection. Liposome and heparin binding assays indicate that only the N-terminal region of NS1 mediates interaction with membranes and that sulfate binding sites common to NS1 structures are not glycosaminoglycan binding interfaces. This report highlights several differences between flavivirus NS1 proteins and contributes to our understanding of their structure-pathogenic function relationships.IMPORTANCE JEV is a major cause of viral encephalitis in Asia. Despite extensive vaccination, epidemics still occur. Nonstructural protein 1 (NS1) plays a role in viral replication, and, because it is secreted, it can exhibit a wide range of interactions with host proteins. NS1 sequence and protein folds are conserved within the Flavivirus genus, but variations in NS1 protein-protein interactions among viruses likely contribute to differences in pathogenesis. Here, we compared characteristics of the C-terminal β-ladder domain of NS1 between flaviviruses, including surface charge, loop flexibility, epitope cross-reactivity, membrane adherence, and glycosaminoglycan binding. These structural features are central to NS1 functionality and may provide insight into the development of diagnostic tests and therapeutics.
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Affiliation(s)
- Thanalai Poonsiri
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
- Health Protection Research Unit on Emerging and Zoonotic Infections, Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Gareth S A Wright
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
- Department of Molecular Microbiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Lance Turtle
- Centre for Global Vaccine Research, Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
- Health Protection Research Unit on Emerging and Zoonotic Infections, Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Tom Solomon
- Health Protection Research Unit on Emerging and Zoonotic Infections, Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Svetlana V Antonyuk
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom
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22
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Giraldo MI, Vargas-Cuartas O, Gallego-Gomez JC, Shi PY, Padilla-Sanabria L, Castaño-Osorio JC, Rajsbaum R. K48-linked polyubiquitination of dengue virus NS1 protein inhibits its interaction with the viral partner NS4B. Virus Res 2017; 246:1-11. [PMID: 29294313 DOI: 10.1016/j.virusres.2017.12.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 12/22/2017] [Accepted: 12/29/2017] [Indexed: 01/08/2023]
Abstract
Dengue virus (DENV) is a member of the Flaviviridae family, which is transmitted to mammalian species through arthropods, and causes dengue fever or severe dengue fever in humans. The DENV genome encodes for multiple nonstructural (NS) proteins including NS1. NS1 plays an essential role in replication by interacting with other viral proteins including NS4B, however how these interactions are regulated during virus infection is not known. By using bioinformatics, mass spectrometry analysis, and co-immunoprecipitation assays, here we show that DENV-NS1 is ubiquitinated on multiples lysine residues during DENV infection, including K189, a lysine residue previously shown to be important for efficient DENV replication. Data from in vitro and cell culture experiments indicate that dengue NS1 undergoes modification with K48-linked polyubiquitin chains, which usually target proteins to the proteasome for degradation. Furthermore, ubiquitinated NS1 was detected in lysates as well as in supernatants of human and mosquito infected cells. Ubiquitin deconjugation of NS1 using the deubiquitinase OTU resulted in increased interaction with the viral protein NS4B suggesting that ubiquitinated NS1 has reduced affinity for NS4B. In support of these data, a K189R mutation on NS1, which abrogates ubiquitination on amino acid residue 189 of NS1, also increased NS1-NS4B interactions. Our work describes a new mechanism of regulation of NS1-NS4B interactions and suggests that ubiquitination of NS1 may affect DENV replication.
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Affiliation(s)
- Maria Isabel Giraldo
- Centro de Investigaciones Biomédicas, Universidad del Quindío, Cra 15 Cl 12N, Armenia, Colombia; Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA.
| | - Oscar Vargas-Cuartas
- Centro de Investigaciones Biomédicas, Universidad del Quindío, Cra 15 Cl 12N, Armenia, Colombia.
| | - Juan Carlos Gallego-Gomez
- Grupo de Medicina Molecular y de Traslación, Universidad de Antioquia, Cra. 51 D No. 62-29, Medellin, Colombia.
| | - Pei-Yong Shi
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA.
| | | | | | - Ricardo Rajsbaum
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA.
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Innate Immune Evasion Mediated by Flaviviridae Non-Structural Proteins. Viruses 2017; 9:v9100291. [PMID: 28991176 PMCID: PMC5691642 DOI: 10.3390/v9100291] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 12/17/2022] Open
Abstract
Flaviviridae-caused diseases are a critical, emerging public health problem worldwide. Flaviviridae infections usually cause severe, acute or chronic diseases, such as liver damage and liver cancer resulting from a hepatitis C virus (HCV) infection and high fever and shock caused by yellow fever. Many researchers worldwide are investigating the mechanisms by which Flaviviridae cause severe diseases. Flaviviridae can interfere with the host’s innate immunity to achieve their purpose of proliferation. For instance, dengue virus (DENV) NS2A, NS2B3, NS4A, NS4B and NS5; HCV NS2, NS3, NS3/4A, NS4B and NS5A; and West Nile virus (WNV) NS1 and NS4B proteins are involved in immune evasion. This review discusses the interplay between viral non-structural Flaviviridae proteins and relevant host proteins, which leads to the suppression of the host’s innate antiviral immunity.
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Suwanmanee S, Luplertlop N. Immunopathogenesis of Dengue Virus-Induced Redundant Cell Death: Apoptosis and Pyroptosis. Viral Immunol 2016; 30:13-19. [PMID: 27860556 DOI: 10.1089/vim.2016.0092] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Dengue virus infection is a self-limited condition, which is of particular importance in tropical and subtropical regions and for which no specific treatment or effective vaccine is available. There are several hypotheses explaining dengue pathogenesis. These usually refer to host immune responses, including antibody-dependent enhancement, cytokine expression, and dengue virus particles including NS1 protein, which lead to cell death by both apoptosis and pyroptosis. A clear understanding of the pathogenesis should facilitate the development of vaccines and therapies. This review focuses on the immunopathogenesis in relation to clinical manifestations and patterns of cell death, focusing on the pathogenesis of severe dengue.
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Affiliation(s)
- San Suwanmanee
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University , Bangkok, Thailand
| | - Natthanej Luplertlop
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University , Bangkok, Thailand
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25
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Rabelo K, Trugilho MRO, Costa SM, Pereira BAS, Moreira OC, Ferreira ATS, Carvalho PC, Perales J, Alves AMB. The effect of the dengue non-structural 1 protein expression over the HepG2 cell proteins in a proteomic approach. J Proteomics 2016; 152:339-354. [PMID: 27826075 DOI: 10.1016/j.jprot.2016.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 10/14/2016] [Accepted: 11/01/2016] [Indexed: 01/01/2023]
Abstract
Dengue is an important mosquito borne viral disease in the world. Dengue virus (DENV) encodes a polyprotein, which is cleaved in ten proteins, including the non-structural protein 1 (NS1). In this work, we analyzed the effect of NS1 expression in one hepatic cell line, HepG2, through a shotgun proteomic approach. Cells were transfected with pcENS1 plasmid, which encodes the DENV2 NS1 protein, or the controls pcDNA3 (negative control) and pMAXGFP (GFP, a protein unrelated to dengue). Expression of NS1 was detected by immunofluorescence, western blot and flow cytometry. We identified 14,138 peptides that mapped to 4,756 proteins in all analyzed conditions. We found 41 and 81 differentially abundant proteins when compared to cells transfected with plasmids pcDNA3 and pMAXGFP, respectively. Besides, 107 proteins were detected only in the presence of NS1. We identified clusters of proteins involved mainly in mRNA process and viral RNA replication. Down regulation expression of one protein (MARCKS), identified by the proteomic analysis, was also confirmed by real time PCR in HepG2 cells infected with DENV2. Identification of proteins modulated by the presence of NS1 may improve our understanding of its role in virus infection and pathogenesis, contributing to development of new therapies and vaccines. BIOLOGICAL SIGNIFICANCE Dengue is an important viral disease, with epidemics in tropical and subtropical regions of the world. The disease is complex, with different manifestations, in which the liver is normally affected. The NS1 is found in infected cells associated with plasma membrane and secreted into the circulation as a soluble multimer. This protein is essential for virus viability, although its function is not elucidated. Some reports indicate that the NS1 can be used as a protective antigen for the development of a dengue vaccine, while others suggest its involvement in viral pathogenesis. In this work, we report an in-depth comprehensive proteomic profiling resulting from the presence of NS1 in HepG2 cells. These results can contribute to a better understanding of the NS1 role during infection.
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Affiliation(s)
- Kíssila Rabelo
- Laboratory of Biotechnology and Physiology of Viral Infections, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Monique R O Trugilho
- Laboratory of Toxinology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Simone M Costa
- Laboratory of Biotechnology and Physiology of Viral Infections, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Bernardo A S Pereira
- Laboratory of Biotechnology and Physiology of Viral Infections, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Otacílio C Moreira
- Laboratory of Molecular Biology and Endemic Diseases, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - André T S Ferreira
- Laboratory of Toxinology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Paulo C Carvalho
- Laboratory for Proteomics and Protein Engineering, Carlos Chagas Institute, Fiocruz, Paraná, Brazil
| | - Jonas Perales
- Laboratory of Toxinology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Ada M B Alves
- Laboratory of Biotechnology and Physiology of Viral Infections, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil.
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26
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Rastogi M, Sharma N, Singh SK. Flavivirus NS1: a multifaceted enigmatic viral protein. Virol J 2016; 13:131. [PMID: 27473856 PMCID: PMC4966872 DOI: 10.1186/s12985-016-0590-7] [Citation(s) in RCA: 161] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 07/26/2016] [Indexed: 12/31/2022] Open
Abstract
Flaviviruses are emerging arthropod-borne viruses representing an immense global health problem. The prominent viruses of this group include dengue virus, yellow fever virus, Japanese encephalitis virus, West Nile virus tick borne encephalitis virus and Zika Virus. These are endemic in many parts of the world. They are responsible for the illness ranging from mild flu like symptoms to severe hemorrhagic, neurologic and cognitive manifestations leading to death. NS1 is a highly conserved non-structural protein among flaviviruses, which exist in diverse forms. The intracellular dimer form of NS1 plays role in genome replication, whereas, the secreted hexamer plays role in immune evasion. The secreted NS1 has been identified as a potential diagnostic marker for early detection of the infections caused by flaviviruses. In addition to the diagnostic marker, the importance of NS1 has been reported in the development of therapeutics. NS1 based subunit vaccines are at various stages of development. The structural details and diverse functions of NS1 have been discussed in detail in this review.
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Affiliation(s)
- Meghana Rastogi
- Institute of Medical Sciences (IMS), Laboratory of Human Molecular Virology & Immunology, Molecular Biology Unit, Faculty of Medicine, Banaras Hindu University, Varanasi, 221005, India
| | - Nikhil Sharma
- Laboratory of Neurovirology and Inflammation Biology, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Hyderabad, 500007, India
| | - Sunit Kumar Singh
- Institute of Medical Sciences (IMS), Laboratory of Human Molecular Virology & Immunology, Molecular Biology Unit, Faculty of Medicine, Banaras Hindu University, Varanasi, 221005, India.
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27
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Electrochemical lateral flow immunosensor for detection and quantification of dengue NS1 protein. Biosens Bioelectron 2016; 77:400-8. [DOI: 10.1016/j.bios.2015.09.048] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/19/2015] [Accepted: 09/22/2015] [Indexed: 12/24/2022]
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28
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Contribution of N-linked glycans on HSV-2 gB to cell-cell fusion and viral entry. Virology 2015; 483:72-82. [PMID: 25965797 DOI: 10.1016/j.virol.2015.04.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 01/30/2015] [Accepted: 04/02/2015] [Indexed: 11/21/2022]
Abstract
HSV-2 is the major cause of genital herpes and its infection increases the risk of HIV-1 acquisition and transmission. HSV-2 glycoprotein B together with glycoproteins D, H and L are indispensable for viral entry, of which gB, as a class III fusogen, plays an essential role. HSV-2 gB has seven potential N-linked glycosylation (N-CHO) sites, but their significance has yet to be determined. For the first time, we systematically analyzed the contributions of N-linked glycans on gB to cell-cell fusion and viral entry. Our results demonstrated that, of the seven potential N-CHO sites on gB, mutation at N390, N483 or N668 decreased cell-cell fusion and viral entry, while mutation at N133 mainly affected protein expression and the production of infectious virus particles by blocking the transport of gB from the endoplasmic reticulum to Golgi. Our findings highlight the significance of N-linked glycans on HSV-2 gB expression and function.
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