scholarly journals A single nonsynonymous mutation on gene encoding E protein of Zika virus leads to increased neurovirulence in vivo

2020 ◽  
Author(s):  
Zhihua Liu ◽  
Yawei Zhang ◽  
Mengli Cheng ◽  
Ningning Ge ◽  
Jiayi Shu ◽  
...  
Keyword(s):  
Zika Virus ◽  
Viral Envelope ◽  
Sequencing Analysis ◽  
Viral Envelope Protein ◽  
Nonsynonymous Mutation ◽  
Genetic Characteristics ◽  
Neonatal Mice ◽  
E Protein ◽  
Wide Range

AbstractZika virus can infect a wide range of tissues including the developmental brain of human fetuses, causing from mild to severe clinical diseases. Whether its genetic characteristics impacts on viral pathogenesis is incompletely understood. We have obtained viral variants through serially passage of a clinical Zika virus isolate (SW01) in neonatal mice in vivo and found some of which exhibited markedly increased virulence and neurotropism. By deep sequencing analysis, the more pathogenic viral variants were found to contain four dominant nonsynonymous nucleotide mutations on genes encoding E and NS2A proteins. Further investigation using molecularly cloned viruses revealed that a single 67D (Aspatic acid) to N (Asparagine) substitution on E protein is sufficient to confer the increased virulence and neurotropism. These findings provide new insight into Zika virus pathogenesis and suggest novel targets for the development of therapeutics.Author SummaryRecent large outbreaks of Zika virus infection worldwide have revealed an association between the viral infection and increased cases of specific neurological problems including Congenital Zika Syndrome (including microcephaly) and adult Guillain–Barré Syndrome. However, the determinants of the increased neurovirulence of Zika virus remain uncertain. One hypothesis is that some unique changes across the Zika viral genome have led to the occurrence of these neurological diseases. To test this hypothesis, we continuously propagated a clinical isolate of contemporary Zika virus (SW01) in neonatal mice brain for 11 times to obtain an mouse central nervous system (CNS) adapted Zika virus (MA-SW01) that showed significantly increased neurovirulence in vivo. We then discovered that a single G to A nucleotide substitution at the 1069 site of Zika virus open reading frame leading to a D (aspartic acid) to N (asparagine) in viral Envelope protein is responsible for the increased neurovirulence. These findings improve our understanding of the neurological pathogenesis of Zika virus and provide clues for the development of antiviral strategy.

scholarly journals Site-specific N-glycosylation analysis of animal cell culture-derived Zika virus proteins

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alexander Pralow ◽  
Alexander Nikolay ◽  
Arnaud Leon ◽  
Yvonne Genzel ◽  
Erdmann Rapp ◽  
...  
Keyword(s):  
Zika Virus ◽  
Animal Cell ◽  
Gradient Centrifugation ◽  
Viral Envelope ◽  
Protein Glycosylation ◽  
High Yield ◽  
Structural Protein ◽  
Site Specific ◽  
E Protein ◽  
The Impact

AbstractHere, we present for the first time, a site-specific N-glycosylation analysis of proteins from a Brazilian Zika virus (ZIKV) strain. The virus was propagated with high yield in an embryo-derived stem cell line (EB66, Valneva SE), and concentrated by g-force step-gradient centrifugation. Subsequently, the sample was proteolytically digested with different enzymes, measured via a LC–MS/MS-based workflow, and analyzed in a semi-automated way using the in-house developed glyXtoolMS software. The viral non-structural protein 1 (NS1) was glycosylated exclusively with high-mannose structures on both potential N-glycosylation sites. In case of the viral envelope (E) protein, no specific N-glycans could be identified with this method. Nevertheless, N-glycosylation could be proved by enzymatic de-N-glycosylation with PNGase F, resulting in a strong MS-signal of the former glycopeptide with deamidated asparagine at the potential N-glycosylation site N444. This confirmed that this site of the ZIKV E protein is highly N-glycosylated but with very high micro-heterogeneity. Our study clearly demonstrates the progress made towards site-specific N-glycosylation analysis of viral proteins, i.e. for Brazilian ZIKV. It allows to better characterize viral isolates, and to monitor glycosylation of major antigens. The method established can be applied for detailed studies regarding the impact of protein glycosylation on antigenicity and human pathogenicity of many viruses including influenza virus, HIV and corona virus.

scholarly journals Two Genetic Differences between Closely Related Zika Virus Strains Determine Pathogenic Outcome in Mice

2020 ◽  
Vol 94 (20) ◽  
Author(s):  
Derek L. Carbaugh ◽  
Shuntai Zhou ◽  
Wes Sanders ◽  
Nathaniel J. Moorman ◽  
Ronald Swanstrom ◽  
...  
Keyword(s):  
Amino Acid ◽  
Mouse Models ◽  
Zika Virus ◽  
Clinical Manifestations ◽  
Amino Acid Sequences ◽  
Viral Envelope ◽  
Laboratory Research ◽  
Balanced Polymorphism ◽  
E Protein ◽  
Virus Strains

ABSTRACT Recent Zika virus (ZIKV) outbreaks and unexpected clinical manifestations of ZIKV infection have prompted an increase in ZIKV-related research. Here, we identify two strain-specific determinants of ZIKV virulence in mice. We found that strain H/PF/2013 caused 100% lethality in Ifnar1−/− mice, whereas PRVABC59 caused no lethality; both strains caused 100% lethality in Ifnar1−/− Ifngr1−/− double-knockout (DKO) mice. Deep sequencing revealed a high-frequency variant in PRVABC59 not present in H/PF/2013: a G-to-T change at nucleotide 1965 producing a Val-to-Leu substitution at position 330 of the viral envelope (E) protein. We show that the V330 variant is lethal on both virus strain backgrounds, whereas the L330 variant is attenuating only on the PRVABC59 background. These results identify a balanced polymorphism in the E protein that is sufficient to attenuate the PRVABC59 strain but not H/PF/2013. The consensus sequences of H/PF/2013 and PRVABC59 differ by 3 amino acids, but these were not responsible for the difference in virulence between the two strains. H/PF/2013 and PRVABC59 differ by an additional 31 noncoding or silent nucleotide changes. We made a panel of chimeric viruses with identical amino acid sequences but nucleotide sequences derived from H/PF/2013 or PRVABC59. We found that 6 nucleotide differences in the 3′ quarter of the H/PF/2013 genome were sufficient to confer virulence in Ifnar1−/− mice. Altogether, our work identifies a large and previously unreported difference in virulence between two commonly used ZIKV strains, in two widely used mouse models of ZIKV pathogenesis (Ifnar1−/− and Ifnar1−/− Ifngr1−/− DKO mice). IMPORTANCE Contemporary ZIKV strains are closely related and often used interchangeably in laboratory research. Here, we identify two strain-specific determinants of ZIKV virulence that are evident in only Ifnar1−/− mice but not Ifnar1−/− Ifngr1−/− DKO mice. These results identify a balanced polymorphism in the E protein that is sufficient to attenuate the PRVABC59 strain but not H/PF/2013. We further identify a second virulence determinant in the H/PF/2013 strain, which is driven by the viral nucleotide sequence but not the amino acid sequence. Altogether, our work identifies a large and previously unreported difference in virulence between two commonly used ZIKV strains, in two widely used mouse models of ZIKV pathogenesis. Our results highlight that even very closely related virus strains can produce significantly different pathogenic phenotypes in common laboratory models.

scholarly journals Transfer of carbohydrates on to nascent glycoprotein of vesicular stomatitis virus

1979 ◽  
Vol 181 (2) ◽  
pp. 295-300 ◽  
Author(s):  
J Kruppa
Keyword(s):  
Vesicular Stomatitis Virus ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Viral Envelope ◽  
Pulse Labelling ◽  
Viral Envelope Protein ◽  
Viral Glycoprotein ◽  
Membrane Bound ◽  
Vesicular Stomatitis

I studied the glycosylation in vivo of a viral envelope protein, the glycoprotein of vesicular stomatitis virus (VSV), by pulse labelling of virus-infected HeLa cells with 3H-labelled monosaccharides (mannose, glucosamine). Radioactivity was incorporated into the fraction of membrane-bound polyribosomes, although metabolic conversion of [3H]-mannose into amino acids was negligible. Dissociation of bound polyribosomes revealed that the radioactively co-purified with the peptidyl-tRNA. The nascent peptides were released by alkaline hydrolysis, immunoprecipitated and analysed by polyacrylamide-gel electrophoresis. It is apparent from the size distribution of the [3H]mannose-labelled nascent chains that attachment of carbohydrate starts when approximately half of the amino acid sequence of the viral glycoprotein has been synthesized.

scholarly journals Rationale for endomyocardial biopsy in the diagnosis of heart disease in children and adults

2021 ◽  
Vol 26 (11) ◽  
pp. 4710
Author(s):  
L. B. Mitrofanova ◽  
B. E. Galkovsky ◽  
I. A. Danilova ◽  
D. S. Lebedev
Keyword(s):  
Heart Transplantation ◽  
Endomyocardial Biopsy ◽  
Immunohistochemical Study ◽  
Immunohistochemical Analysis ◽  
Arrhythmogenic Right Ventricular Dysplasia ◽  
Viral Envelope ◽  
Viral Envelope Protein ◽  
Exact Test ◽  
Myocardial Diseases ◽  
Wide Range

Endomyocardial biopsy (EMB) is the method of choice for diagnosing a wide range of myocardial diseases.Aim. To assess the rationale for diagnostic EMB in children and adults.Material and methods. Morphological and statistical analysis of 2803 diagnostic EMBs in adults (n=811) and children (n=83), including those in heart transplantation (n=1909), was carried out.Results. In 231 (28%) cases, adults were diagnosed with myocarditis, of which in 6 patients — granulomatous, in 5 — eosinophilic and in 6 — lymphocytic-macrophage myocarditis after coronavirus infection. In children, myocarditis was found in 22 cases (27%). Arrhythmogenic right ventricular dysplasia took the second place in detection rate in children and adults. Immunohistochemical study revealed viral envelope protein 1 (VP1) antigen of enteroviruses in one third of myocarditis cases, and in half — other cardiotropic viruses. Dotted dystrophin expression was observed in myocarditis. A correlation was established between the perforin expression and myocarditis presence (Pearson χ2=27,8; Fisher's exact test=27,3; p=0,01).Conclusion. Analysis of diagnostic EMB results confirmed its rationale in adults and children not only for heart transplantation, but also for identifying cardiac pathology, including for myocarditis diagnosis. It has been shown that immunohistochemical study with antiviral antibodies can be considered as an alternative method for detecting viral infection. An immunohistochemical analysis for perforin and dystrophin can be recommended as additional morphological markers of myocarditis.

scholarly journals Murine Trophoblast Stem Cells and Their Differentiated Cells Attenuate Zika Virus In Vitro by Reducing Glycosylation of the Viral Envelope Protein

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3085
Author(s):  
Biswas Neupane ◽  
Mona Fendereski ◽  
Farzana Nazneen ◽  
Yan-Lin Guo ◽  
Fengwei Bai
Keyword(s):  
Stem Cells ◽  
Zika Virus ◽  
Viral Envelope ◽  
Viral Envelope Protein ◽  
Zikv Infection ◽  
Trophoblast Stem Cells ◽  
Differentiated Cells ◽  
Trophoblast Stem ◽  
Stage Embryo

Zika virus (ZIKV) infection during pregnancy can cause devastating fetal neuropathological abnormalities, including microcephaly. Most studies of ZIKV infection in pregnancy have focused on post-implantation stage embryos. Currently, we have limited knowledge about how a pre-implantation stage embryo deals with a viral infection. This study investigates ZIKV infection on mouse trophoblast stem cells (TSCs) and their in vitro differentiated TSCs (DTSCs), which resemble the cellular components of the trophectoderm layer of the blastocyst that later develops into the placenta. We demonstrate that TSCs and DTSCs are permissive to ZIKV infection; however, ZIKV propagated in TSCs and DTSCs exhibit substantially lower infectivity, as shown in vitro and in a mouse model compared to ZIKV that was generated in Vero cells or mouse embryonic fibroblasts (MEFs). We further show that the low infectivity of ZIKV propagated in TSCs and DTSCs is associated with a reduced level of glycosylation on the viral envelope (E) proteins, which are essential for ZIKV to establish initial attachment by binding to cell surface glycosaminoglycans (GAGs). The decreased level of glycosylation on ZIKV E is, at least, partially due to the low-level expression of a glycosylation-related gene, Hexa, in TSCs and DTSCs. Furthermore, this finding is not limited to ZIKV since similar observations have been made as to the chikungunya virus (CHIKV) and West Nile virus (WNV) propagated in TSCs and DTSCs. In conclusion, our results reveal a novel phenomenon suggesting that murine TSCs and their differentiated cells may have adapted a cellular glycosylation system that can limit viral infectivity by altering the glycosylation of viral envelope proteins, therefore serving as a unique, innate anti-viral mechanism in the pre-implantation stage embryo.

scholarly journals Mutation of a Single Envelope N-Linked Glycosylation Site Enhances the Pathogenicity of Bovine Leukemia Virus

2015 ◽  
Vol 89 (17) ◽  
pp. 8945-8956 ◽  
Author(s):  
Alix de Brogniez ◽  
Amel Baya Bouzar ◽  
Jean-Rock Jacques ◽  
Jean-Philippe Cosse ◽  
Nicolas Gillet ◽  
...  
Keyword(s):  
Bovine Leukemia Virus ◽  
Reverse Genetics ◽  
Immune Escape ◽  
Leukemia Virus ◽  
Glycosylation Site ◽  
Viral Envelope ◽  
Viral Envelope Protein ◽  
Cell Infection

ABSTRACTViruses have coevolved with their host to ensure efficient replication and transmission without inducing excessive pathogenicity that would indirectly impair their persistence. This is exemplified by the bovine leukemia virus (BLV) system in which lymphoproliferative disorders develop in ruminants after latency periods of several years. In principle, the equilibrium reached between the virus and its host could be disrupted by emergence of more pathogenic strains. Intriguingly but fortunately, such a hyperpathogenic BLV strain was never observed in the field or designedin vitro. In this study, we sought to understand the role of envelope N-linked glycosylation with the hypothesis that this posttranslational modification could either favor BLV infection by allowing viral entry or allow immune escape by using glycans as a shield. Using reverse genetics of an infectious molecular provirus, we identified a N-linked envelope glycosylation site (N230) that limits viral replication and pathogenicity. Indeed, mutation N230E unexpectedly leads to enhanced fusogenicity and protein stability.IMPORTANCEInfection by retroviruses requires the interaction of the viral envelope protein (SU) with a membrane-associated receptor allowing fusion and release of the viral genomic RNA into the cell. We show that N-linked glycosylation of the bovine leukemia virus (BLV) SU protein is, as expected, essential for cell infectionin vitro. Consistently, mutation of all glycosylation sites of a BLV provirus destroys infectivityin vivo. However, single mutations do not significantly modify replicationin vivo. Instead, a particular mutation at SU codon 230 increases replication and accelerates pathogenesis. This unexpected observation has important consequences in terms of disease control and managing.

scholarly journals Macrocyclic peptides exhibit antiviral effects against influenza virus HA and prevent pneumonia in animal models

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Makoto Saito ◽  
Yasushi Itoh ◽  
Fumihiko Yasui ◽  
Tsubasa Munakata ◽  
Daisuke Yamane ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Cynomolgus Macaque ◽  
Severe Pneumonia ◽  
Neuraminidase Inhibitor ◽  
Influenza Viruses ◽  
Viral Envelope ◽  
Viral Envelope Protein ◽  
Wide Range ◽  
Macrocyclic Peptides

AbstractMost anti-influenza drugs currently used, such as oseltamivir and zanamivir, inhibit the enzymatic activity of neuraminidase. However, neuraminidase inhibitor-resistant viruses have already been identified from various influenza virus isolates. Here, we report the development of a class of macrocyclic peptides that bind the influenza viral envelope protein hemagglutinin, named iHA. Of 28 iHAs examined, iHA-24 and iHA-100 have inhibitory effects on the in vitro replication of a wide range of Group 1 influenza viruses. In particular, iHA-100 bifunctionally inhibits hemagglutinin-mediated adsorption and membrane fusion through binding to the stalk domain of hemagglutinin. Moreover, iHA-100 shows powerful efficacy in inhibiting the growth of highly pathogenic influenza viruses and preventing severe pneumonia at later stages of infection in mouse and non-human primate cynomolgus macaque models. This study shows the potential for developing cyclic peptides that can be produced more efficiently than antibodies and have multiple functions as next-generation, mid-sized biomolecules.

scholarly journals Mechanistic insights into Zika virus NS3 helicase inhibition by Epigallocatechin-3-gallate

2019 ◽  
Author(s):  
Deepak Kumar ◽  
Nitin Sharma ◽  
Murali Aarthy ◽  
Sanjeev Kumar Singh ◽  
Rajanish Giri
Keyword(s):  
Zika Virus ◽  
Rna Binding ◽  
Significant Inhibition ◽  
Viral Envelope ◽  
Health Concern ◽  
Viral Envelope Protein ◽  
Host Proteins ◽  
Ic50 Value ◽  
Green Tea Polyphenol ◽  
Inhibitory Interactions

ABSTRACTSince 2007, repeated outbreaks of Zika virus (ZIKV) has affected millions of people worldwide and created global health concern with major complications like microcephaly and Guillain Barre’s syndrome. Generally, ZIKV transmits through mosquitoes (Aedes aegypti) like other flaviviruses, but reports show blood transfusion and sexual mode of ZIKV transmission which further makes the situation alarming. Till date, there is not a single Zika specific licensed drug or vaccine present in the market. However, in recent months, several antiviral molecules have been screened against viral and host proteins. Among those, (−)-Epigallocatechin-3-gallate (EGCG), a green tea polyphenol has shown great virucidal potential against flaviviruses including ZIKV. However, the mechanistic understanding of EGCG targeting viral proteins is not yet entirely deciphered except little is known about its interaction with viral envelope protein and viral protease. Since literature has shown significant inhibitory interactions of EGCG against various kinases and bacterial DNA gyrases; we designed our study to find inhibitory actions of EGCG against ZIKV NS3 helicase. NS3 helicase is playing a significant role in viral replication by unwinding RNA after hydrolyzing NTP. We employed molecular docking and simulation approach and found significant interactions at ATPase site and also at RNA binding site. Further, the enzymatic assay has shown significant inhibition of NTPase activity with an IC50 value of 295.7 nM and Ki of 0.387 ± 0.034 µM. Our study suggests the possibility that EGCG could be considered as prime backbone molecule for further broad-spectrum and multitargeted inhibitor development against ZIKV and other flaviviruses.

scholarly journals Coreceptor Phenotype of Natural Human Immunodeficiency Virus with Nef Deleted Evolves In Vivo, Leading to Increased Virulence

2002 ◽  
Vol 76 (14) ◽  
pp. 6966-6973 ◽  
Author(s):  
Andreas Jekle ◽  
Birgit Schramm ◽  
Prerana Jayakumar ◽  
Verena Trautner ◽  
Dominique Schols ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Ex Vivo ◽  
Viral Envelope ◽  
Viral Envelope Protein ◽  
Cell Infection ◽  
Human Lymphoid Cell ◽  
Human Immunodeficiency Virus Strain ◽  
Immunodeficiency Virus

ABSTRACT The Sydney Blood Bank Cohort is a group of patients with slowly progressive infection by a human immunodeficiency virus strain containing spontaneous deletions within the nef long terminal repeat region. In 1999, 18 years after the initial infection, one of the members (D36) developed AIDS. In this work, we used an ex vivo human lymphoid cell culture system to analyze two viral isolates obtained from this patient, one prior to the onset of AIDS in 1995 and one after disease progression in 1999. Both D36 isolates were less potent in depleting CD4+ T cells than a reference dualtropic, nef-bearing viral isolate. However, the 1999 isolate was measurably more cytotoxic to CD4+ T cells than the 1995 isolate. Interestingly, although both isolates were nearly equally potent in depleting CCR5+ CD4+ T cells, the cytotoxic effect of the 1999 isolate toward CCR5− CD4+ T cells was significantly higher. Furthermore, GHOST cell infection assays and blocking experiments with the CXCR4 inhibitor AMD3100 showed that the later D36 1999 isolate could infect both CCR5+ and CCR5− CXCR4+ cells efficiently, while infection by the 1995 isolate was nearly completely restricted to CCR5+ cells. Sequence analysis of the V1/V2 and V3 regions of the viral envelope protein gp120 revealed that the more efficient CXCR4 usage of the later isolate might be caused by an additional potential N-glycosylation site in the V1/V2 loop. In conclusion, these data show that an in vivo evolution of the tropism of this nef-deleted strain toward an X4 phenotype was associated with a higher cytopathic potential and progression to AIDS.

scholarly journals Envelope Protein Glycosylation Mediates Zika Virus Pathogenesis

2019 ◽  
Vol 93 (12) ◽  
Author(s):  
Derek L. Carbaugh ◽  
Ralph S. Baric ◽  
Helen M. Lazear
Keyword(s):  
Zika Virus ◽  
Envelope Protein ◽  
Glycosylation Site ◽  
Viral Envelope ◽  
Protein Glycosylation ◽  
Guillain Barre Syndrome ◽  
Viral Loads ◽  
E Protein ◽  
Guillain Barré Syndrome ◽  
Guillain Barré

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.

Sign in / Sign up

Export Citation Format

Share Document