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Ishida K, Yagi H, Kato Y, Morita E. N-linked glycosylation of flavivirus E protein contributes to viral particle formation. PLoS Pathog 2023; 19:e1011681. [PMID: 37819933 PMCID: PMC10593244 DOI: 10.1371/journal.ppat.1011681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 10/23/2023] [Accepted: 09/12/2023] [Indexed: 10/13/2023] Open
Abstract
In the case of the Japanese encephalitis virus (JEV), the envelope protein (E), a major component of viral particles, contains a highly conserved N-linked glycosylation site (E: N154). Glycosylation of the E protein is thought to play an important role in the ability of the virus to attach to target cells during transmission; however, its role in viral particle formation and release remains poorly understood. In this study, we investigated the role of N-glycosylation of flaviviral structural proteins in viral particle formation and secretion by introducing mutations in viral structural proteins or cellular factors involved in glycoprotein transport and processing. The number of secreted subviral particles (SVPs) was significantly reduced in N154A, a glycosylation-null mutant, but increased in D67N, a mutant containing additional glycosylation sites, indicating that the amount of E glycosylation regulates the release of SVPs. SVP secretion was reduced in cells deficient in galactose, sialic acid, and N-acetylglucosamine modifications in the Golgi apparatus; however, these reductions were not significant, suggesting that glycosylation mainly plays a role in pre-Golgi transport. Fluorescent labeling of SVPs using a split green fluorescent protein (GFP) system and time-lapse imaging by retention using selective hooks (RUSH) system revealed that the glycosylation-deficient mutant was arrested before endoplasmic reticulum (ER)- Golgi transport. However, the absence of ERGIC-53 and ERGIC-L, ER-Golgi transport cargo receptors that recognize sugar chains on cargo proteins, does not impair SVP secretion. In contrast, the solubility of the N154A mutant of E or the N15A/T17A mutant of prM in cells was markedly lower than that of the wild type, and proteasome-mediated rapid degradation of these mutants was observed, indicating the significance of glycosylation of both prM and E in proper protein folding and assembly of viral particles in the ER.
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Affiliation(s)
- Kotaro Ishida
- Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Japan
- Division of Biomolecular Function, Bioresources Science, United Graduate School of Agricultural Sciences, Iwate University, Morioka, Japan
| | - Hirokazu Yagi
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Eiji Morita
- Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Japan
- Division of Biomolecular Function, Bioresources Science, United Graduate School of Agricultural Sciences, Iwate University, Morioka, Japan
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2
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Pustijanac E, Buršić M, Talapko J, Škrlec I, Meštrović T, Lišnjić D. Tick-Borne Encephalitis Virus: A Comprehensive Review of Transmission, Pathogenesis, Epidemiology, Clinical Manifestations, Diagnosis, and Prevention. Microorganisms 2023; 11:1634. [PMID: 37512806 PMCID: PMC10383662 DOI: 10.3390/microorganisms11071634] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/13/2023] [Accepted: 06/20/2023] [Indexed: 07/30/2023] Open
Abstract
Tick-borne encephalitis virus (TBEV), a member of the Flaviviridae family, can cause serious infection of the central nervous system in humans, resulting in potential neurological complications and fatal outcomes. TBEV is primarily transmitted to humans through infected tick bites, and the viral agent circulates between ticks and animals, such as deer and small mammals. The occurrence of the infection aligns with the seasonal activity of ticks. As no specific antiviral therapy exists for TBEV infection, treatment approaches primarily focus on symptomatic relief and support. Active immunization is highly effective, especially for individuals in endemic areas. The burden of TBEV infections is increasing, posing a growing health concern. Reported incidence rates rose from 0.4 to 0.9 cases per 100,000 people between 2015 and 2020. The Baltic and Central European countries have the highest incidence, but TBE is endemic across a wide geographic area. Various factors, including social and environmental aspects, improved medical awareness, and advanced diagnostics, have contributed to the observed increase. Diagnosing TBEV infection can be challenging due to the non-specific nature of the initial symptoms and potential co-infections. Accurate diagnosis is crucial for appropriate management, prevention of complications, and effective control measures. In this comprehensive review, we summarize the molecular structure of TBEV, its transmission and circulation in natural environments, the pathogenesis of TBEV infection, the epidemiology and global distribution of the virus, associated risk factors, clinical manifestations, and diagnostic approaches. By improving understanding of these aspects, we aim to enhance knowledge and promote strategies for timely and accurate diagnosis, appropriate management, and the implementation of effective control measures against TBEV infections.
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Affiliation(s)
- Emina Pustijanac
- Faculty of Natural Sciences, Juraj Dobrila University of Pula, 52100 Pula, Croatia
| | - Moira Buršić
- Faculty of Natural Sciences, Juraj Dobrila University of Pula, 52100 Pula, Croatia
| | - Jasminka Talapko
- Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Crkvena 21, 31000 Osijek, Croatia
| | - Ivana Škrlec
- Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Crkvena 21, 31000 Osijek, Croatia
| | - Tomislav Meštrović
- University Centre Varaždin, University North, 42000 Varaždin, Croatia
- Institute for Health Metrics and Evaluation and the Department of Health Metrics Sciences, University of Washington, Seattle, WA 98195, USA
| | - Dubravka Lišnjić
- Faculty of Dental Medicine and Health, Josip Juraj Strossmayer University of Osijek, Crkvena 21, 31000 Osijek, Croatia
- Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Josipa Huttlera 4, 31000 Osijek, Croatia
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3
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van Bree JW, Visser I, Duyvestyn JM, Aguilar-Bretones M, Marshall EM, van Hemert MJ, Pijlman GP, van Nierop GP, Kikkert M, Rockx BH, Miesen P, Fros JJ. Novel approaches for the rapid development of rationally designed arbovirus vaccines. One Health 2023; 16:100565. [PMID: 37363258 PMCID: PMC10288159 DOI: 10.1016/j.onehlt.2023.100565] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 05/09/2023] [Accepted: 05/12/2023] [Indexed: 06/28/2023] Open
Abstract
Vector-borne diseases, including those transmitted by mosquitoes, account for more than 17% of infectious diseases worldwide. This number is expected to rise with an increased spread of vector mosquitoes and viruses due to climate change and man-made alterations to ecosystems. Among the most common, medically relevant mosquito-borne infections are those caused by arthropod-borne viruses (arboviruses), especially members of the genera Flavivirus and Alphavirus. Arbovirus infections can cause severe disease in humans, livestock and wildlife. Severe consequences from infections include congenital malformations as well as arthritogenic, haemorrhagic or neuroinvasive disease. Inactivated or live-attenuated vaccines (LAVs) are available for a small number of arboviruses; however there are no licensed vaccines for the majority of these infections. Here we discuss recent developments in pan-arbovirus LAV approaches, from site-directed attenuation strategies targeting conserved determinants of virulence to universal strategies that utilize genome-wide re-coding of viral genomes. In addition to these approaches, we discuss novel strategies targeting mosquito saliva proteins that play an important role in virus transmission and pathogenesis in vertebrate hosts. For rapid pre-clinical evaluations of novel arbovirus vaccine candidates, representative in vitro and in vivo experimental systems are required to assess the desired specific immune responses. Here we discuss promising models to study attenuation of neuroinvasion, neurovirulence and virus transmission, as well as antibody induction and potential for cross-reactivity. Investigating broadly applicable vaccination strategies to target the direct interface of the vertebrate host, the mosquito vector and the viral pathogen is a prime example of a One Health strategy to tackle human and animal diseases.
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Affiliation(s)
- Joyce W.M. van Bree
- Laboratory of Virology, Wageningen University & Research, Wageningen, the Netherlands
| | - Imke Visser
- Department of Viroscience, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Jo M. Duyvestyn
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands
| | | | - Eleanor M. Marshall
- Department of Viroscience, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Martijn J. van Hemert
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Gorben P. Pijlman
- Laboratory of Virology, Wageningen University & Research, Wageningen, the Netherlands
| | | | - Marjolein Kikkert
- Department of Medical Microbiology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Barry H.G. Rockx
- Department of Viroscience, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Pascal Miesen
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500, HB, Nijmegen, the Netherlands
| | - Jelke J. Fros
- Laboratory of Virology, Wageningen University & Research, Wageningen, the Netherlands
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4
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Zimna M, Brzuska G, Salát J, Svoboda P, Baranska K, Szewczyk B, Růžek D, Krol E. Functional characterization and immunogenicity of a novel vaccine candidate against tick-borne encephalitis virus based on Leishmania-derived virus-like particles. Antiviral Res 2023; 209:105511. [PMID: 36581050 DOI: 10.1016/j.antiviral.2022.105511] [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: 10/27/2022] [Revised: 12/09/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022]
Abstract
Tick-borne encephalitis virus (TBEV) is a major cause of neurological infections in many regions of central, eastern and northern Europe and northern Asia. In approximately 15% of cases, TBEV infections lead to the development of severe encephalitis or meningitis. The main route of TBEV transmission is tick bites; however, ingestion of dairy products from infected animals (goats, cattle and sheep) is also a frequent cause of the disease. Therefore, vaccination of livestock in virus endemic regions could also contribute to the decrease in TBEV infection among humans. Although few vaccines against TBEV based on inactivated viruses are available for humans, due to high costs, vaccination is not mandatory in most of the affected countries. Moreover, there is still no vaccine for veterinary use. Here, we present a characterization and immunogenicity study of a new potential TBEV vaccine based on virus-like particles (VLPs) produced in Leishmania tarentolae cells. VLPs, which mimic native viral particles but do not contain genetic material, show good immunogenic potential. For the first time, we showed that the protozoan L. tarentolae expression system can be successfully used for the production of TBEV virus-like particles with highly efficient production. We confirmed that TBEV recombinant structural proteins (prM/M and E) from VLPs are highly recognized by neutralizing antibodies in in vitro analyses. Therefore, VLPs in combination with AddaVax adjuvant were used in immunization studies in a mouse model. VLPs proved to be highly immunogenic and induced the production of high levels of neutralizing antibodies. In a challenge experiment, immunization with VLPs provided full protection from lethal TBE in mice. Thus, we suggest that Leishmania-derived VLPs may be a good candidate for a safe alternative human vaccine with high efficiency of production. Moreover, this potential vaccine candidate may constitute a low-cost candidate for veterinary use.
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Affiliation(s)
- Marta Zimna
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland.
| | - Gabriela Brzuska
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland.
| | - Jiří Salát
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Hudcova 70, CZ, 62100, Brno, Czech Republic; Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ, 37005, Ceske Budejovice, Czech Republic.
| | - Pavel Svoboda
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Hudcova 70, CZ, 62100, Brno, Czech Republic; Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ, 37005, Ceske Budejovice, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 735/5, CZ, 62500, Brno, Czech Republic; Faculty of Veterinary Medicine, University of Veterinary Sciences Brno, Palackeho Tr. 1946/1, 61242, Brno, Czech Republic.
| | - Klaudia Baranska
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland.
| | - Boguslaw Szewczyk
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland.
| | - Daniel Růžek
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Hudcova 70, CZ, 62100, Brno, Czech Republic; Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ, 37005, Ceske Budejovice, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 735/5, CZ, 62500, Brno, Czech Republic.
| | - Ewelina Krol
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland.
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5
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Molecular Organisation of Tick-Borne Encephalitis Virus. Viruses 2022; 14:v14040792. [PMID: 35458522 PMCID: PMC9027435 DOI: 10.3390/v14040792] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/06/2022] [Accepted: 04/07/2022] [Indexed: 01/19/2023] Open
Abstract
Tick-borne encephalitis virus (TBEV) is a pathogenic, enveloped, positive-stranded RNA virus in the family Flaviviridae. Structural studies of flavivirus virions have primarily focused on mosquito-borne species, with only one cryo-electron microscopy (cryo-EM) structure of a tick-borne species published. Here, we present a 3.3 Å cryo-EM structure of the TBEV virion of the Kuutsalo-14 isolate, confirming the overall organisation of the virus. We observe conformational switching of the peripheral and transmembrane helices of M protein, which can explain the quasi-equivalent packing of the viral proteins and highlights their importance in stabilising membrane protein arrangement in the virion. The residues responsible for M protein interactions are highly conserved in TBEV but not in the structurally studied Hypr strain, nor in mosquito-borne flaviviruses. These interactions may compensate for the lower number of hydrogen bonds between E proteins in TBEV compared to the mosquito-borne flaviviruses. The structure reveals two lipids bound in the E protein which are important for virus assembly. The lipid pockets are comparable to those recently described in mosquito-borne Zika, Spondweni, Dengue, and Usutu viruses. Our results thus advance the understanding of tick-borne flavivirus architecture and virion-stabilising interactions.
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6
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Salata C, Moutailler S, Attoui H, Zweygarth E, Decker L, Bell-Sakyi L. How relevant are in vitro culture models for study of tick-pathogen interactions? Pathog Glob Health 2021; 115:437-455. [PMID: 34190676 PMCID: PMC8635668 DOI: 10.1080/20477724.2021.1944539] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Although tick-borne infectious diseases threaten human and animal health worldwide, with constantly increasing incidence, little knowledge is available regarding vector-pathogen interactions and pathogen transmission. In vivo laboratory study of these subjects using live, intact ticks is expensive, labor-intensive, and challenging from the points of view of biosafety and ethics. Several in vitro models have been developed, including over 70 continuous cell lines derived from multiple tick species and a variety of tick organ culture systems, facilitating many research activities. However, some limitations have to be considered in the translation of the results from the in vitro environment to the in vivo situation of live, intact ticks, and vertebrate hosts. In this review, we describe the available in vitro models and selected results from their application to the study of tick-borne viruses, bacteria, and protozoa, where possible comparing these results to studies in live, intact ticks. Finally, we highlight the strengths and weaknesses of in vitro tick culture models and their essential role in tick-borne pathogen research.
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Affiliation(s)
- Cristiano Salata
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Sara Moutailler
- Laboratoire De Santé Animale, Anses, INRAE, Ecole Nationale Vétérinaire d’Alfort, UMR BIPAR, Maisons-Alfort, France
| | - Houssam Attoui
- Department of Animal Health, UMR1161 Virologie, INRAE, Ecole Nationale Vétérinaire d’Alfort, ANSES, Université Paris-Est, Maisons-Alfort, France
| | - Erich Zweygarth
- The Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
| | - Lygia Decker
- Department of Preventive Veterinary Medicine, School of Veterinary Medicine, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Lesley Bell-Sakyi
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
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7
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Brzuska G, Pastuch-Gawolek G, Krawczyk M, Szewczyk B, Krol E. Anti-Tick-Borne Encephalitis Virus Activity of Novel Uridine Glycoconjugates Containing Amide or/and 1,2,3-Triazole Moiety in the Linker Structure. Pharmaceuticals (Basel) 2020; 13:ph13120460. [PMID: 33322151 PMCID: PMC7764612 DOI: 10.3390/ph13120460] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/11/2020] [Accepted: 12/11/2020] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) transmitted by ticks is a pathogen of great medical importance. As still no effective antiviral treatment is available, in the present study, a series of uridine glycoconjugates containing amide or/and 1,2,3-triazole moiety in the linker structure was synthesized and evaluated for the antiviral activity against two strains of TBEV: a highly virulent Hypr strain and less virulent Neudoerfl strain, using standardized previously in vitro assays. Our data have shown that four compounds from the series (18–21) possess strong activity against both TBEV strains. The half maximal inhibitory concentration (IC50) values of compounds 18–21 were between 15.1 and 3.7 μM depending on the virus strain, which along with low cytotoxicity resulted in high values of the selectivity index (SI). The obtained results suggest that these compounds may be promising candidates for further development of new therapies against flaviviruses.
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Affiliation(s)
- Gabriela Brzuska
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland; (G.B.); (B.S.)
| | - Gabriela Pastuch-Gawolek
- Department of Organic Chemistry, Bioorganic Chemistry and Biotechnology, Faculty of Chemistry, Silesian University of Technology, Krzywoustego 4, 44-100 Gliwice, Poland; (G.P.-G.); (M.K.)
- Biotechnology Centre, Silesian University of Technology, Krzywoustego 8, 44-100 Gliwice, Poland
| | - Monika Krawczyk
- Department of Organic Chemistry, Bioorganic Chemistry and Biotechnology, Faculty of Chemistry, Silesian University of Technology, Krzywoustego 4, 44-100 Gliwice, Poland; (G.P.-G.); (M.K.)
- Biotechnology Centre, Silesian University of Technology, Krzywoustego 8, 44-100 Gliwice, Poland
| | - Boguslaw Szewczyk
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland; (G.B.); (B.S.)
| | - Ewelina Krol
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland; (G.B.); (B.S.)
- Correspondence: ; Tel.: +48-58-523-63-83
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8
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Evans DeWald L, Starr C, Butters T, Treston A, Warfield KL. Iminosugars: A host-targeted approach to combat Flaviviridae infections. Antiviral Res 2020; 184:104881. [PMID: 32768411 PMCID: PMC7405907 DOI: 10.1016/j.antiviral.2020.104881] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/07/2020] [Accepted: 07/13/2020] [Indexed: 12/12/2022]
Abstract
N-linked glycosylation is the most common form of protein glycosylation and is required for the proper folding, trafficking, and/or receptor binding of some host and viral proteins. As viruses lack their own glycosylation machinery, they are dependent on the host's machinery for these processes. Certain iminosugars are known to interfere with the N-linked glycosylation pathway by targeting and inhibiting α-glucosidases I and II in the endoplasmic reticulum (ER). Perturbing ER α-glucosidase function can prevent these enzymes from removing terminal glucose residues on N-linked glycans, interrupting the interaction between viral glycoproteins and host chaperone proteins that is necessary for proper folding of the viral protein. Iminosugars have demonstrated broad-spectrum antiviral activity in vitro and in vivo against multiple viruses. This review discusses the broad activity of iminosugars against Flaviviridae. Iminosugars have shown favorable activity against multiple members of the Flaviviridae family in vitro and in murine models of disease, although the activity and mechanism of inhibition can be virus-specfic. While iminosugars are not currently approved for the treatment of viral infections, their potential use as future host-targeted antiviral (HTAV) therapies continues to be investigated.
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Affiliation(s)
| | - Chloe Starr
- Emergent BioSolutions, Gaithersburg, MD, 20879, USA
| | | | | | - Kelly L. Warfield
- Emergent BioSolutions, Gaithersburg, MD, 20879, USA,Corresponding author. 400 Professional Drive, Gaithersburg, MD, 20879, USA
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9
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Abstract
The flavivirus genus encompasses more than 75 unique viruses, including dengue virus which accounts for almost 390 million global infections annually. Flavivirus infection can result in a myriad of symptoms ranging from mild rash and flu-like symptoms, to severe encephalitis and even hemorrhagic fever. Efforts to combat the impact of these viruses have been hindered due to limited antiviral drug and vaccine development. However, the advancement of knowledge in the structural biology of flaviviruses over the last 25 years has produced unique perspectives for the identification of potential therapeutic targets. With particular emphasis on the assembly and maturation stages of the flavivirus life cycle, it is the goal of this review to comparatively analyze the structural similarities between flaviviruses to provide avenues for new research and innovation.
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Affiliation(s)
- Conrrad M R Nicholls
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
| | - Madhumati Sevvana
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
| | - Richard J Kuhn
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States; Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN, United States.
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10
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Lattová E, Straková P, Pokorná-Formanová P, Grubhoffer L, Bell-Sakyi L, Zdráhal Z, Palus M, Ruzek D. Comprehensive N-glycosylation mapping of envelope glycoprotein from tick-borne encephalitis virus grown in human and tick cells. Sci Rep 2020; 10:13204. [PMID: 32764711 PMCID: PMC7411051 DOI: 10.1038/s41598-020-70082-2] [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] [Received: 04/18/2020] [Accepted: 07/22/2020] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is the causative agent of severe human neuroinfections that most commonly occur after a tick bite. N-Glycosylation of the TBEV envelope (E) glycoprotein is critical for virus egress in mammalian cells, but not in tick cells. In addition, glycans have been reported to mask specific antigenic sites from recognition by neutralizing antibodies. In this regard, the main purpose of our study was to investigate the profile of N-glycans linked to the E protein of TBEV when grown in human neuronal cells and compare it to the profile of virus grown in tick cells. Mass spectrometric analysis revealed significant differences in these profiles. High-mannose glycan with five mannose residues (Man5GlcNAc2), a complex biantennary galactosylated structure with core fucose (Gal2GlcNAc2Man3GlcNAc2Fuc), and a group of hybrid glycans with the composition Gal0-1GlcNAc1Man3-5GlcNAc2Fuc0-1 were confirmed as the main asparagine-linked oligosaccharides on the surface of TBEV derived from human neuronal cells. The observed pattern was supported by examination of the glycopeptides, providing additional information about the glycosylation site in the E protein. In contrast, the profile of TBEV grown in tick cells showed that paucimannose (Man3-4 GlcNAc2Fuc0-1) and high-mannose structures with five and six mannoses (Man5-6GlcNAc2) were major glycans on the viral surface. The reported results complement existing crystallography and cryoelectron tomography data on the E protein structure and could be instrumental for designing carbohydrate-binding antiviral agents active against TBEV.
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Affiliation(s)
- Erika Lattová
- Central European Institute of Technology, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic.
| | - Petra Straková
- Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic
| | | | - Libor Grubhoffer
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, 37005, Ceske Budejovice, Czech Republic
| | - Lesley Bell-Sakyi
- Department of Infection Biology and Microbiome, Institute of Infection, Ecological and Veterinary Sciences, University of Liverpool, 146 Brownlow Hill, Liverpool, L3 5RF, UK
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic.,National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic
| | - Martin Palus
- Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic.,Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, 37005, Ceske Budejovice, Czech Republic
| | - Daniel Ruzek
- Veterinary Research Institute, Hudcova 296/70, 62100, Brno, Czech Republic. .,Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, 37005, Ceske Budejovice, Czech Republic.
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11
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Flavivirus Envelope Protein Glycosylation: Impacts on Viral Infection and Pathogenesis. J Virol 2020; 94:JVI.00104-20. [PMID: 32161171 DOI: 10.1128/jvi.00104-20] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 03/10/2020] [Indexed: 02/06/2023] Open
Abstract
Flaviviruses encode one, two, or no N-linked glycosylation sites on their envelope proteins. Glycosylation can impact virus interactions with cell surface attachment factors and also may impact virion stability and virus replication. Envelope protein glycosylation has been identified as a virulence determinant for multiple flaviviruses, but the mechanisms by which glycosylation mediates pathogenesis remain unclear. In this Gem, we summarize current knowledge on flavivirus envelope protein glycosylation and its impact on viral infection and pathogenesis.
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12
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Bos S, Viranaicken W, Frumence E, Li G, Desprès P, Zhao RY, Gadea G. The Envelope Residues E152/156/158 of Zika Virus Influence the Early Stages of Virus Infection in Human Cells. Cells 2019; 8:cells8111444. [PMID: 31731738 PMCID: PMC6912530 DOI: 10.3390/cells8111444] [Citation(s) in RCA: 10] [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: 09/06/2019] [Revised: 11/07/2019] [Accepted: 11/13/2019] [Indexed: 12/11/2022] Open
Abstract
Emerging infections of mosquito-borne Zika virus (ZIKV) pose an increasing threat to human health, as documented over the recent years in South Pacific islands and the Americas in recent years. To better understand molecular mechanisms underlying the increase in human cases with severe pathologies, we recently demonstrated the functional roles of structural proteins capsid (C), pre-membrane (prM), and envelop (E) of ZIKV epidemic strains with the initiation of viral infection in human cells. Specifically, we found that the C-prM region contributes to permissiveness of human host cells to ZIKV infection and ZIKV-induced cytopathic effects, whereas the E protein is associated with viral attachment and early infection. In the present study, we further characterize ZIKV E proteins by investigating the roles of residues isoleucine 152 (Ile152), threonine 156 (Thr156), and histidine 158 (His158) (i.e., the E-152/156/158 residues), which surround a unique N-glycosylation site (E-154), in permissiveness of human host cells to epidemic ZIKV infection. For comparison purpose, we generated mutant molecular clones of epidemic BeH819015 (BR15) and historical MR766-NIID (MR766) strains that carry each other's E-152/156/158 residues, respectively. We observed that the BR15 mutant containing the E-152/156/158 residues from MR766 was less infectious in A549-Dual™ cells than parental virus. In contrast, the MR766 mutant containing E-152/156/158 residues from BR15 displayed increased infectivity. The observed differences in infectivity were, however, not correlated with changes in viral binding onto host-cells or cellular responses to viral infection. Instead, the E-152/156/158 residues from BR15 were associated with an increased efficiency of viral membrane fusion inside infected cells due to conformational changes of E protein that enhance exposure of the fusion loop. Our data highlight an important contribution of E-152/156/158 residues to the early steps of ZIKV infection in human cells.
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Affiliation(s)
- Sandra Bos
- Université de la Réunion, INSERM U1187, CNRS UMR 9192, IRD UMR 249, Unité Mixte Processus Infectieux en Milieu Insulaire Tropical, Plateforme Technologique CYROI, 94791 Sainte Clotilde, La Réunion, France; (S.B.); (W.V.); (E.F.); (P.D.)
| | - Wildriss Viranaicken
- Université de la Réunion, INSERM U1187, CNRS UMR 9192, IRD UMR 249, Unité Mixte Processus Infectieux en Milieu Insulaire Tropical, Plateforme Technologique CYROI, 94791 Sainte Clotilde, La Réunion, France; (S.B.); (W.V.); (E.F.); (P.D.)
| | - Etienne Frumence
- Université de la Réunion, INSERM U1187, CNRS UMR 9192, IRD UMR 249, Unité Mixte Processus Infectieux en Milieu Insulaire Tropical, Plateforme Technologique CYROI, 94791 Sainte Clotilde, La Réunion, France; (S.B.); (W.V.); (E.F.); (P.D.)
| | - Ge Li
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA;
| | - Philippe Desprès
- Université de la Réunion, INSERM U1187, CNRS UMR 9192, IRD UMR 249, Unité Mixte Processus Infectieux en Milieu Insulaire Tropical, Plateforme Technologique CYROI, 94791 Sainte Clotilde, La Réunion, France; (S.B.); (W.V.); (E.F.); (P.D.)
| | - Richard Y. Zhao
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA;
- Department of Microbiology and Immunology, University of Maryland, Baltimore, MD 21201, USA
- Institute of Global Health, University of Maryland, Baltimore, MD 21201, USA
- Institute of Human Virology, University of Maryland, Baltimore, MD 21201, USA
- Correspondence: (R.Y.Z.); (G.G.); Tel.: +33-262-262-938-806 (G.G.)
| | - Gilles Gadea
- Université de la Réunion, INSERM U1187, CNRS UMR 9192, IRD UMR 249, Unité Mixte Processus Infectieux en Milieu Insulaire Tropical, Plateforme Technologique CYROI, 94791 Sainte Clotilde, La Réunion, France; (S.B.); (W.V.); (E.F.); (P.D.)
- Correspondence: (R.Y.Z.); (G.G.); Tel.: +33-262-262-938-806 (G.G.)
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13
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A method for rapid and high-yield production of the tick-borne encephalitis virus E and DIII recombinant proteins in E. coli with preservation of the antigenic properties. Ticks Tick Borne Dis 2019; 10:935-941. [DOI: 10.1016/j.ttbdis.2019.04.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 04/17/2019] [Accepted: 04/27/2019] [Indexed: 12/30/2022]
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14
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Envelope Protein Glycosylation Mediates Zika Virus Pathogenesis. J Virol 2019; 93:JVI.00113-19. [PMID: 30944176 DOI: 10.1128/jvi.00113-19] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 03/23/2019] [Indexed: 12/25/2022] Open
Abstract
Zika virus (ZIKV) is an emerging mosquito-borne flavivirus. Recent ZIKV outbreaks have produced serious human disease, including neurodevelopmental malformations (congenital Zika syndrome) and Guillain-Barré syndrome. These outcomes were not associated with ZIKV infection prior to 2013, raising the possibility that viral genetic changes could contribute to new clinical manifestations. All contemporary ZIKV isolates encode an N-linked glycosylation site in the envelope (E) protein (N154), but this glycosylation site is absent in many historical ZIKV isolates. Here, we investigated the role of E protein glycosylation in ZIKV pathogenesis using two contemporary Asian-lineage strains (H/PF/2013 and PRVABC59) and the historical African-lineage strain (MR766). We found that glycosylated viruses were highly pathogenic in Ifnar1-/- mice. In contrast, nonglycosylated viruses were attenuated, producing lower viral loads in the serum and brain when inoculated subcutaneously but remaining neurovirulent when inoculated intracranially. These results suggest that E glycosylation is advantageous in the periphery but not within the brain. Accordingly, we found that glycosylation facilitated infection of cells expressing the lectins dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) or DC-SIGN-related (DC-SIGNR), suggesting that inefficient infection of lectin-expressing leukocytes could contribute to the attenuation of nonglycosylated ZIKV in mice.IMPORTANCE It is unclear why the ability of Zika virus (ZIKV) to cause serious disease, including Guillain-Barré syndrome and birth defects, was not recognized until recent outbreaks. One contributing factor could be genetic differences between contemporary ZIKV strains and historical ZIKV strains. All isolates from recent outbreaks encode a viral envelope protein that is glycosylated, whereas many historical ZIKV strains lack this glycosylation. We generated nonglycosylated ZIKV mutants from contemporary and historical strains and evaluated their virulence in mice. We found that nonglycosylated viruses were attenuated and produced lower viral loads in serum and brains. Our studies suggest that envelope protein glycosylation contributes to ZIKV pathogenesis, possibly by facilitating attachment to and infection of lectin-expressing leukocytes.
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15
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Krol E, Wandzik I, Brzuska G, Eyer L, Růžek D, Szewczyk B. Antiviral Activity of Uridine Derivatives of 2-Deoxy Sugars against Tick-Borne Encephalitis Virus. Molecules 2019; 24:molecules24061129. [PMID: 30901934 PMCID: PMC6471225 DOI: 10.3390/molecules24061129] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 03/16/2019] [Accepted: 03/18/2019] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is a causative agent of tick-borne encephalitis (TBE), one of the most important human infections involving the central nervous system. Although effective vaccines are available on the market, they are recommended only in endemic areas. Despite many attempts, there are still no specific antiviral therapies for TBEV treatment. Previously, we synthesized a series of uridine derivatives of 2-deoxy sugars and proved that some compounds show antiviral activity against viruses from the Flaviviridae and Orthomyxoviridae families targeting the late steps of the N-glycosylation process, affecting the maturation of viral proteins. In this study, we evaluated a series of uridine derivatives of 2-deoxy sugars for their antiviral properties against two strains of the tick-borne encephalitis virus; the highly virulent TBEV strain Hypr and the less virulent strain Neudoerfl. Four compounds (2, 4, 10, and 11) showed significant anti-TBEV activity with IC50 values ranging from 1.4 to 10.2 µM and low cytotoxicity. The obtained results indicate that glycosylation inhibitors, which may interact with glycosylated membrane TBEV E and prM proteins, might be promising candidates for future antiviral therapies against TBEV.
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Affiliation(s)
- Ewelina Krol
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland.
| | - Ilona Wandzik
- Department of Organic Chemistry, Bioorganic Chemistry and Biotechnology, Faculty of Chemistry, Silesian University of Technology, Krzywoustego 4, 44-100 Gliwice, Poland.
- Biotechnology Center, Silesian University of Technology, Krzywoustego 8, 44-100 Gliwice, Poland.
| | - Gabriela Brzuska
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland.
| | - Luděk Eyer
- Department of Virology, Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic.
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37005 Ceske Budejovice, Czech Republic.
| | - Daniel Růžek
- Department of Virology, Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic.
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37005 Ceske Budejovice, Czech Republic.
| | - Boguslaw Szewczyk
- Department of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland.
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16
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Orlov AA, Khvatov EV, Koruchekov AA, Nikitina AA, Zolotareva AD, Eletskaya AA, Kozlovskaya LI, Palyulin VA, Horvath D, Osolodkin DI, Varnek A. Getting to Know the Neighbours with GTM: The Case of Antiviral Compounds. Mol Inform 2019; 38:e1800166. [DOI: 10.1002/minf.201800166] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 02/02/2019] [Indexed: 01/16/2023]
Affiliation(s)
- Alexey A. Orlov
- FSBSI “Chumakov FSC R&D IBP RAS” Moscow 108819 Russia
- Lomonosov Moscow State University Moscow 119991 Russia
| | | | - Alexander A. Koruchekov
- FSBSI “Chumakov FSC R&D IBP RAS” Moscow 108819 Russia
- Lomonosov Moscow State University Moscow 119991 Russia
| | - Anastasia A. Nikitina
- FSBSI “Chumakov FSC R&D IBP RAS” Moscow 108819 Russia
- Lomonosov Moscow State University Moscow 119991 Russia
| | - Anastasia D. Zolotareva
- FSBSI “Chumakov FSC R&D IBP RAS” Moscow 108819 Russia
- Sechenov First Moscow State Medical University Moscow 119991 Russia
| | - Anastasia A. Eletskaya
- FSBSI “Chumakov FSC R&D IBP RAS” Moscow 108819 Russia
- Lomonosov Moscow State University Moscow 119991 Russia
| | - Liubov I. Kozlovskaya
- FSBSI “Chumakov FSC R&D IBP RAS” Moscow 108819 Russia
- Sechenov First Moscow State Medical University Moscow 119991 Russia
| | | | - Dragos Horvath
- Laboratory of Chemoinformatics, Faculty of ChemistryUniversity of Strasbourg Strasbourg 67081 France
| | - Dmitry I. Osolodkin
- FSBSI “Chumakov FSC R&D IBP RAS” Moscow 108819 Russia
- Lomonosov Moscow State University Moscow 119991 Russia
- Sechenov First Moscow State Medical University Moscow 119991 Russia
| | - Alexandre Varnek
- Laboratory of Chemoinformatics, Faculty of ChemistryUniversity of Strasbourg Strasbourg 67081 France
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17
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Abstract
Tick-borne encephalitis virus (TBEV), a member of the genus Flavivirus within the family Flaviviridae, causes fatal encephalitis with severe sequelae in humans. TBEV is
prevalent over a wide area of the Eurasian continent including Europe, Russia, Far-Eastern Asia, and Japan. While it was previously thought that TBEV was not endemic in Japan, the first
confirmed case of serologically diagnosed TBE was reported in 1993 in the southern area of Hokkaido Prefecture, Japan. In addition, TBEV has been isolated from dogs, wild rodents and ticks
in the area. Our epizootiological survey indicated that endemic foci of TBEV were maintained in Hokkaido and other areas of Honshu. TBEV can be divided into three subtypes based on
phylogenetic analyses. The Japanese isolates were classified as the Far Eastern subtype, which causes severe neural disorders with a higher mortality rate up to 30%. However, how viral
replication and pathogenicity contribute to the neurological manifestations remains unclear. Recent studies have revealed distinctive mechanisms of TBEV pathogenicity and viral genetic
factors associated with virulence. This review discusses the recent findings regarding the epidemiology and pathogenesis of TBEV.
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Affiliation(s)
- Kentaro Yoshii
- Laboratory of Public Health, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
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18
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Vechtova P, Sterbova J, Sterba J, Vancova M, Rego ROM, Selinger M, Strnad M, Golovchenko M, Rudenko N, Grubhoffer L. A bite so sweet: the glycobiology interface of tick-host-pathogen interactions. Parasit Vectors 2018; 11:594. [PMID: 30428923 PMCID: PMC6236881 DOI: 10.1186/s13071-018-3062-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 08/14/2018] [Indexed: 11/10/2022] Open
Abstract
Vector-borne diseases constitute 17% of all infectious diseases in the world; among the blood-feeding arthropods, ticks transmit the highest number of pathogens. Understanding the interactions between the tick vector, the mammalian host and the pathogens circulating between them is the basis for the successful development of vaccines against ticks or the tick-transmitted pathogens as well as for the development of specific treatments against tick-borne infections. A lot of effort has been put into transcriptomic and proteomic analyses; however, the protein-carbohydrate interactions and the overall glycobiology of ticks and tick-borne pathogens has not been given the importance or priority deserved. Novel (bio)analytical techniques and their availability have immensely increased the possibilities in glycobiology research and thus novel information in the glycobiology of ticks and tick-borne pathogens is being generated at a faster pace each year. This review brings a comprehensive summary of the knowledge on both the glycosylated proteins and the glycan-binding proteins of the ticks as well as the tick-transmitted pathogens, with emphasis on the interactions allowing the infection of both the ticks and the hosts by various bacteria and tick-borne encephalitis virus.
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Affiliation(s)
- Pavlina Vechtova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic. .,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic.
| | - Jarmila Sterbova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Jan Sterba
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Marie Vancova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Ryan O M Rego
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Martin Selinger
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Martin Strnad
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Maryna Golovchenko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic
| | - Nataliia Rudenko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic
| | - Libor Grubhoffer
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
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19
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Sager G, Gabaglio S, Sztul E, Belov GA. Role of Host Cell Secretory Machinery in Zika Virus Life Cycle. Viruses 2018; 10:E559. [PMID: 30326556 PMCID: PMC6213159 DOI: 10.3390/v10100559] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 10/11/2018] [Accepted: 10/12/2018] [Indexed: 12/16/2022] Open
Abstract
The high human cost of Zika virus infections and the rapid establishment of virus circulation in novel areas, including the United States, present an urgent need for countermeasures against this emerging threat. The development of an effective vaccine against Zika virus may be problematic because of the cross reactivity of the antibodies with other flaviviruses leading to antibody-dependent enhancement of infection. Moreover, rapidly replicating positive strand RNA viruses, including Zika virus, generate large spectrum of mutant genomes (quasi species) every replication round, allowing rapid selection of variants resistant to drugs targeting virus-specific proteins. On the other hand, viruses are ultimate cellular parasites and rely on the host metabolism for every step of their life cycle, thus presenting an opportunity to manipulate host processes as an alternative approach to suppress virus replication and spread. Zika and other flaviviruses critically depend on the cellular secretory pathway, which transfers proteins and membranes from the ER through the Golgi to the plasma membrane, for virion assembly, maturation and release. In this review, we summarize the current knowledge of interactions of Zika and similar arthropod-borne flaviviruses with the cellular secretory machinery with a special emphasis on virus-specific changes of the secretory pathway. Identification of the regulatory networks and effector proteins required to accommodate the trafficking of virions, which represent a highly unusual cargo for the secretory pathway, may open an attractive and virtually untapped reservoir of alternative targets for the development of superior anti-viral drugs.
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Affiliation(s)
- Garrett Sager
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham AL 35294, UK.
| | - Samuel Gabaglio
- Department of Veterinary Medicine, Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA.
| | - Elizabeth Sztul
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham AL 35294, UK.
| | - George A Belov
- Department of Veterinary Medicine, Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA.
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20
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Bagdonaite I, Wandall HH. Global aspects of viral glycosylation. Glycobiology 2018; 28:443-467. [PMID: 29579213 PMCID: PMC7108637 DOI: 10.1093/glycob/cwy021] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 02/10/2018] [Accepted: 03/21/2018] [Indexed: 12/15/2022] Open
Abstract
Enveloped viruses encompass some of the most common human pathogens causing infections of different severity, ranging from no or very few symptoms to lethal disease as seen with the viral hemorrhagic fevers. All enveloped viruses possess an envelope membrane derived from the host cell, modified with often heavily glycosylated virally encoded glycoproteins important for infectivity, viral particle formation and immune evasion. While N-linked glycosylation of viral envelope proteins is well characterized with respect to location, structure and site occupancy, information on mucin-type O-glycosylation of these proteins is less comprehensive. Studies on viral glycosylation are often limited to analysis of recombinant proteins that in most cases are produced in cell lines with a glycosylation capacity different from the capacity of the host cells. The glycosylation pattern of the produced recombinant glycoproteins might therefore be different from the pattern on native viral proteins. In this review, we provide a historical perspective on analysis of viral glycosylation, and summarize known roles of glycans in the biology of enveloped human viruses. In addition, we describe how to overcome the analytical limitations by using a global approach based on mass spectrometry to identify viral O-glycosylation in virus-infected cell lysates using the complex enveloped virus herpes simplex virus type 1 as a model. We underscore that glycans often pay important contributions to overall protein structure, function and immune recognition, and that glycans represent a crucial determinant for vaccine design. High throughput analysis of glycosylation on relevant glycoprotein formulations, as well as data compilation and sharing is therefore important to identify consensus glycosylation patterns for translational applications.
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Affiliation(s)
- Ieva Bagdonaite
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, Copenhagen N, Denmark
| | - Hans H Wandall
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, Blegdamsvej 3B, Copenhagen N, Denmark
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21
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Pulkkinen LIA, Butcher SJ, Anastasina M. Tick-Borne Encephalitis Virus: A Structural View. Viruses 2018; 10:v10070350. [PMID: 29958443 PMCID: PMC6071267 DOI: 10.3390/v10070350] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 06/25/2018] [Accepted: 06/27/2018] [Indexed: 12/11/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is a growing health concern. It causes a severe disease that can lead to permanent neurological complications or death and the incidence of TBEV infections is constantly rising. Our understanding of TBEV’s structure lags behind that of other flaviviruses, but has advanced recently with the publication of a high-resolution structure of the TBEV virion. The gaps in our knowledge include: aspects of receptor binding, replication and virus assembly. Furthermore, TBEV has mostly been studied in mammalian systems, even though the virus’ interaction with its tick hosts is a central part of its life cycle. Elucidating these aspects of TBEV biology are crucial for the development of TBEV antivirals, as well as the improvement of diagnostics. In this review, we summarise the current structural knowledge on TBEV, bringing attention to the current gaps in our understanding, and propose further research that is needed to truly understand the structural-functional relationship of the virus and its hosts.
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Affiliation(s)
- Lauri I A Pulkkinen
- HiLIFE-Institute of Biotechnology, University of Helsinki, 00790 Helsinki, Finland.
- Faculty of Biological and Environmental Sciences, University of Helsinki, 00790 Helsinki, Finland.
| | - Sarah J Butcher
- HiLIFE-Institute of Biotechnology, University of Helsinki, 00790 Helsinki, Finland.
- Faculty of Biological and Environmental Sciences, University of Helsinki, 00790 Helsinki, Finland.
| | - Maria Anastasina
- HiLIFE-Institute of Biotechnology, University of Helsinki, 00790 Helsinki, Finland.
- Faculty of Biological and Environmental Sciences, University of Helsinki, 00790 Helsinki, Finland.
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22
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Lindqvist R, Upadhyay A, Överby AK. Tick-Borne Flaviviruses and the Type I Interferon Response. Viruses 2018; 10:E340. [PMID: 29933625 PMCID: PMC6071234 DOI: 10.3390/v10070340] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 06/15/2018] [Accepted: 06/19/2018] [Indexed: 12/13/2022] Open
Abstract
Flaviviruses are globally distributed pathogens causing millions of human infections every year. Flaviviruses are arthropod-borne viruses and are mainly transmitted by either ticks or mosquitoes. Mosquito-borne flaviviruses and their interactions with the innate immune response have been well-studied and reviewed extensively, thus this review will discuss tick-borne flaviviruses and their interactions with the host innate immune response.
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Affiliation(s)
- Richard Lindqvist
- Department of Clinical Microbiology, Virology, Umeå University, SE-90185 Umeå, Sweden.
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, SE-90187 Umeå, Sweden.
- Umeå Centre for Microbial Research (UCMR), Umeå University, SE-90187 Umeå, Sweden.
| | - Arunkumar Upadhyay
- Department of Clinical Microbiology, Virology, Umeå University, SE-90185 Umeå, Sweden.
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, SE-90187 Umeå, Sweden.
- Umeå Centre for Microbial Research (UCMR), Umeå University, SE-90187 Umeå, Sweden.
| | - Anna K Överby
- Department of Clinical Microbiology, Virology, Umeå University, SE-90185 Umeå, Sweden.
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, SE-90187 Umeå, Sweden.
- Umeå Centre for Microbial Research (UCMR), Umeå University, SE-90187 Umeå, Sweden.
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23
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Kellman EM, Offerdahl DK, Melik W, Bloom ME. Viral Determinants of Virulence in Tick-Borne Flaviviruses. Viruses 2018; 10:v10060329. [PMID: 29914165 PMCID: PMC6024809 DOI: 10.3390/v10060329] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 06/12/2018] [Accepted: 06/15/2018] [Indexed: 12/27/2022] Open
Abstract
Tick-borne flaviviruses have a global distribution and cause significant human disease, including encephalitis and hemorrhagic fever, and often result in neurologic sequelae. There are two distinct properties that determine the neuropathogenesis of a virus. The ability to invade the central nervous system (CNS) is referred to as the neuroinvasiveness of the agent, while the ability to infect and damage cells within the CNS is referred to as its neurovirulence. Examination of laboratory variants, cDNA clones, natural isolates with varying pathogenicity, and virally encoded immune evasion strategies have contributed extensively to our understanding of these properties. Here we will review the major viral determinants of virulence that contribute to pathogenesis and influence both neuroinvasiveness and neurovirulence properties of tick-borne flaviviruses, focusing particularly on the envelope protein (E), nonstructural protein 5 (NS5), and the 3′ untranslated region (UTR).
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Affiliation(s)
- Eliza M Kellman
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT 59840, USA.
| | - Danielle K Offerdahl
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT 59840, USA.
| | - Wessam Melik
- School of Medical Sciences, Orebro University, SE-703 62 Örebro, Sweden.
| | - Marshall E Bloom
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT 59840, USA.
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Yap SSL, Nguyen-Khuong T, Rudd PM, Alonso S. Dengue Virus Glycosylation: What Do We Know? Front Microbiol 2017; 8:1415. [PMID: 28791003 PMCID: PMC5524768 DOI: 10.3389/fmicb.2017.01415] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 07/12/2017] [Indexed: 12/04/2022] Open
Abstract
In many infectious diseases caused by either viruses or bacteria, pathogen glycoproteins play important roles during the infection cycle, ranging from entry to successful intracellular replication and host immune evasion. Dengue is no exception. Dengue virus glycoproteins, envelope protein (E) and non-structural protein 1 (NS1) are two popular sub-unit vaccine candidates. E protein on the virion surface is the major target of neutralizing antibodies. NS1 which is secreted during DENV infection has been shown to induce a variety of host responses through its binding to several host factors. However, despite their critical role in disease and protection, the glycosylated variants of these two proteins and their biological importance have remained understudied. In this review, we seek to provide a comprehensive summary of the current knowledge on protein glycosylation in DENV, and its role in virus biogenesis, host cell receptor interaction and disease pathogenesis.
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Affiliation(s)
- Sally S L Yap
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, and Immunology program, Life Sciences Institute, National University of SingaporeSingapore, Singapore
| | - Terry Nguyen-Khuong
- Analytics Group, Bioprocessing Technology Institute, A∗STARSingapore, Singapore
| | - Pauline M Rudd
- Analytics Group, Bioprocessing Technology Institute, A∗STARSingapore, Singapore
| | - Sylvie Alonso
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, and Immunology program, Life Sciences Institute, National University of SingaporeSingapore, Singapore
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Abstract
Zika virus (ZIKV) had remained a relatively obscure flavivirus until a recent series of outbreaks accompanied by unexpectedly severe clinical complications brought this virus into the spotlight as causing an infection of global public health concern. In this review, we discuss the history and epidemiology of ZIKV infection, recent outbreaks in Oceania and the emergence of ZIKV in the Western Hemisphere, newly ascribed complications of ZIKV infection, including Guillain-Barré syndrome and microcephaly, potential interactions between ZIKV and dengue virus, and the prospects for the development of antiviral agents and vaccines.
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26
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A Single Amino Acid Substitution in the M Protein Attenuates Japanese Encephalitis Virus in Mammalian Hosts. J Virol 2015; 90:2676-89. [PMID: 26656690 DOI: 10.1128/jvi.01176-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 11/30/2015] [Indexed: 02/04/2023] Open
Abstract
UNLABELLED Japanese encephalitis virus (JEV) membrane (M) protein plays important structural roles in the processes of fusion and maturation of progeny virus during cellular infection. The M protein is anchored in the viral membrane, and its ectodomain is composed of a flexible N-terminal loop and a perimembrane helix. In this study, we performed site-directed mutagenesis on residue 36 of JEV M protein and showed that the resulting mutation had little or no effect on the entry process but greatly affected virus assembly in mammalian cells. Interestingly, this mutant virus had a host-dependent phenotype and could develop a wild-type infection in insect cells. Experiments performed on infectious virus as well as in a virus-like particle (VLP) system indicate that the JEV mutant expresses structural proteins but fails to form infectious particles in mammalian cells. Using a mouse model for JEV pathogenesis, we showed that the mutation conferred complete attenuation in vivo. The production of JEV neutralizing antibodies in challenged mice was indicative of the immunogenicity of the mutant virus in vivo. Together, our results indicate that the introduction of a single mutation in the M protein, while being tolerated in insect cells, strongly impacts JEV infection in mammalian hosts. IMPORTANCE JEV is a mosquito-transmitted flavivirus and is a medically important pathogen in Asia. The M protein is thought to be important for accommodating the structural rearrangements undergone by the virion during viral assembly and may play additional roles in the JEV infectious cycle. In the present study, we show that a sole mutation in the M protein impairs the JEV infection cycle in mammalian hosts but not in mosquito cells. This finding highlights differences in flavivirus assembly pathways among hosts. Moreover, infection of mice indicated that the mutant was completely attenuated and triggered a strong immune response to JEV, thus providing new insights for further development of JEV vaccines.
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Weisheit S, Villar M, Tykalová H, Popara M, Loecherbach J, Watson M, Růžek D, Grubhoffer L, de la Fuente J, Fazakerley JK, Bell-Sakyi L. Ixodes scapularis and Ixodes ricinus tick cell lines respond to infection with tick-borne encephalitis virus: transcriptomic and proteomic analysis. Parasit Vectors 2015; 8:599. [PMID: 26582129 PMCID: PMC4652421 DOI: 10.1186/s13071-015-1210-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 11/11/2015] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Ixodid ticks are important vectors of a wide variety of viral, bacterial and protozoan pathogens of medical and veterinary importance. Although several studies have elucidated tick responses to bacteria, little is known about the tick response to viruses. To gain insight into the response of tick cells to flavivirus infection, the transcriptomes and proteomes of two Ixodes spp cell lines infected with the flavivirus tick-borne encephalitis virus (TBEV) were analysed. METHODS RNA and proteins were isolated from the Ixodes scapularis-derived cell line IDE8 and the Ixodes ricinus-derived cell line IRE/CTVM19, mock-infected or infected with TBEV, on day 2 post-infection (p.i.) when virus production was increasing, and on day 6 p.i. when virus production was decreasing. RNA-Seq and mass spectrometric technologies were used to identify changes in abundance of, respectively, transcripts and proteins. Functional analyses were conducted on selected transcripts using RNA interference (RNAi) for gene knockdown in tick cells infected with the closely-related but less pathogenic flavivirus Langat virus (LGTV). RESULTS Differential expression analysis using DESeq resulted in totals of 43 and 83 statistically significantly differentially-expressed transcripts in IDE8 and IRE/CTVM19 cells, respectively. Mass spectrometry detected 76 and 129 statistically significantly differentially-represented proteins in IDE8 and IRE/CTVM19 cells, respectively. Differentially-expressed transcripts and differentially-represented proteins included some that may be involved in innate immune and cell stress responses. Knockdown of the heat-shock proteins HSP90, HSP70 and gp96, the complement-associated protein Factor H and the protease trypsin resulted in increased LGTV replication and production in at least one tick cell line, indicating a possible antiviral role for these proteins. Knockdown of RNAi-associated proteins Argonaute and Dicer, which were included as positive controls, also resulted in increased LGTV replication and production in both cell lines, confirming their role in the antiviral RNAi pathway. CONCLUSIONS This systems biology approach identified several molecules that may be involved in the tick cell innate immune response against flaviviruses and highlighted that ticks, in common with other invertebrate species, have other antiviral responses in addition to RNAi.
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Affiliation(s)
- Sabine Weisheit
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, Scotland, EH25 9RG, UK.
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, UK.
- Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, 0377, Norway.
| | - Margarita Villar
- SaBio. Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM, Ronda de Toledo s/n, Ciudad Real, 13005, Spain.
| | - Hana Tykalová
- Faculty of Science, University of South Bohemia and Biology Centre, Institute of Parasitology, Czech Academy of Sciences, Branisovska 31, České Budějovice (Budweis), 37005, Czech Republic.
| | - Marina Popara
- SaBio. Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM, Ronda de Toledo s/n, Ciudad Real, 13005, Spain.
| | - Julia Loecherbach
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, Scotland, EH25 9RG, UK.
| | - Mick Watson
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, Scotland, EH25 9RG, UK.
| | - Daniel Růžek
- Faculty of Science, University of South Bohemia and Biology Centre, Institute of Parasitology, Czech Academy of Sciences, Branisovska 31, České Budějovice (Budweis), 37005, Czech Republic.
- Veterinary Research Institute, Hudcova 70, Brno, 62100, Czech Republic.
| | - Libor Grubhoffer
- Faculty of Science, University of South Bohemia and Biology Centre, Institute of Parasitology, Czech Academy of Sciences, Branisovska 31, České Budějovice (Budweis), 37005, Czech Republic.
| | - José de la Fuente
- SaBio. Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM, Ronda de Toledo s/n, Ciudad Real, 13005, Spain.
- Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK, 74078, USA.
| | - John K Fazakerley
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, Scotland, EH25 9RG, UK.
- The Pirbright Institute, Ash Road, Pirbright, Surrey, GU24 0NF, UK.
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Roby JA, Setoh YX, Hall RA, Khromykh AA. Post-translational regulation and modifications of flavivirus structural proteins. J Gen Virol 2015; 96:1551-69. [PMID: 25711963 DOI: 10.1099/vir.0.000097] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Flaviviruses are a group of single-stranded, positive-sense RNA viruses that generally circulate between arthropod vectors and susceptible vertebrate hosts, producing significant human and veterinary disease burdens. Intensive research efforts have broadened our scientific understanding of the replication cycles of these viruses and have revealed several elegant and tightly co-ordinated post-translational modifications that regulate the activity of viral proteins. The three structural proteins in particular - capsid (C), pre-membrane (prM) and envelope (E) - are subjected to strict regulatory modifications as they progress from translation through virus particle assembly and egress. The timing of proteolytic cleavage events at the C-prM junction directly influences the degree of genomic RNA packaging into nascent virions. Proteolytic maturation of prM by host furin during Golgi transit facilitates rearrangement of the E proteins at the virion surface, exposing the fusion loop and thus increasing particle infectivity. Specific interactions between the prM and E proteins are also important for particle assembly, as prM acts as a chaperone, facilitating correct conformational folding of E. It is only once prM/E heterodimers form that these proteins can be secreted efficiently. The addition of branched glycans to the prM and E proteins during virion transit also plays a key role in modulating the rate of secretion, pH sensitivity and infectivity of flavivirus particles. The insights gained from research into post-translational regulation of structural proteins are beginning to be applied in the rational design of improved flavivirus vaccine candidates and make attractive targets for the development of novel therapeutics.
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Affiliation(s)
- Justin A Roby
- 1Australian Infectious Diseases Research Centre, The University of Queensland, Australia 2School of Chemistry and Molecular Biosciences, The University of Queensland, Australia
| | - Yin Xiang Setoh
- 1Australian Infectious Diseases Research Centre, The University of Queensland, Australia 2School of Chemistry and Molecular Biosciences, The University of Queensland, Australia
| | - Roy A Hall
- 1Australian Infectious Diseases Research Centre, The University of Queensland, Australia 2School of Chemistry and Molecular Biosciences, The University of Queensland, Australia
| | - Alexander A Khromykh
- 1Australian Infectious Diseases Research Centre, The University of Queensland, Australia 2School of Chemistry and Molecular Biosciences, The University of Queensland, Australia
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