Antibody to the E3 Glycoprotein Protects Mice against Lethal Venezuelan Equine Encephalitis Virus Infection

ABSTRACT Six monoclonal antibodies were isolated that exhibited specificity for a furin cleavage site deletion mutant (V3526) of Venezuelan equine encephalitis virus (VEEV). These antibodies comprise a single competition group and bound the E3 glycoprotein of VEEV subtype I viruses but failed to bind the E3 glycoprotein of other alphaviruses. These antibodies neutralized V3526 virus infectivity but did not neutralize the parental strain of Trinidad donkey (TrD) VEEV. However, the E3-specific antibodies did inhibit the production of virus from VEEV TrD-infected cells. In addition, passive immunization of mice demonstrated that antibody to the E3 glycoprotein provided protection against lethal VEEV TrD challenge. This is the first recognition of a protective epitope in the E3 glycoprotein. Furthermore, these results indicate that E3 plays a critical role late in the morphogenesis of progeny virus after E3 appears on the surfaces of infected cells.

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Venezuelan Equine Encephalitis Virus Capsid Protein Inhibits Nuclear Import in Mammalian but Not in Mosquito Cells

Journal of Virology ◽

10.1128/jvi.02330-07 ◽

2008 ◽

Vol 82 (8) ◽

pp. 4028-4041 ◽

Cited By ~ 62

Author(s):

Svetlana Atasheva ◽

Natalia Garmashova ◽

Ilya Frolov ◽

Elena Frolova

Keyword(s):

Capsid Protein ◽

Nuclear Import ◽

Critical Role ◽

The United States ◽

Venezuelan Equine Encephalitis Virus ◽

Encephalitis Virus ◽

Venezuelan Equine Encephalitis ◽

Equine Encephalitis Virus ◽

Small Proteins ◽

Mosquito Cells

ABSTRACT Venezuelan equine encephalitis virus (VEEV) represents a continuous public health threat in the United States. It has the ability to cause fatal disease in humans and in horses and other domestic animals. We recently demonstrated that replicating VEEV interferes with cellular transcription and uses this phenomenon as a means of downregulating a cellular antiviral response. VEEV capsid protein was found to play a critical role in this process, and its ∼35-amino-acid-long peptide, fused with green fluorescent protein, functioned as efficiently as did the entire capsid. We detected a significant fraction of VEEV capsid associated with nuclear envelope, which suggested that this protein might regulate nucleocytoplasmic trafficking. In this study, we demonstrate that VEEV capsid and its N-terminal sequence efficiently inhibit multiple receptor-mediated nuclear import pathways but have no effect on the passive diffusion of small proteins. The capsid protein of the Old World alphavirus Sindbis virus and the VEEV capsid, with a previously defined frameshift mutation, were found to have no detectable effect on nuclear import. Importantly, the VEEV capsid did not noticeably interfere with nuclear import in mosquito cells, and this might play a critical role in the ability of the virus to develop a persistent, life-long infection in mosquito vectors. These findings demonstrate a new aspect of VEEV-host cell interactions, and the results of this study are likely applicable to other New World alphaviruses, such as eastern and western equine encephalitis viruses.

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Structure of a Venezuelan equine encephalitis virus assembly intermediate isolated from infected cells

Virology ◽

10.1016/j.virol.2010.07.009 ◽

2010 ◽

Vol 406 (2) ◽

pp. 261-269 ◽

Cited By ~ 14

Author(s):

Kristen Lamb ◽

G.L. Lokesh ◽

Michael Sherman ◽

Stanley Watowich

Keyword(s):

Virus Assembly ◽

Venezuelan Equine Encephalitis Virus ◽

Encephalitis Virus ◽

Venezuelan Equine Encephalitis ◽

Equine Encephalitis Virus ◽

Infected Cells ◽

Assembly Intermediate

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Venezuelan equine encephalitis virus non-structural protein 3 (nsP3) interacts with RNA helicases DDX1 and DDX3 in infected cells

Antiviral Research ◽

10.1016/j.antiviral.2016.04.008 ◽

2016 ◽

Vol 131 ◽

pp. 49-60 ◽

Cited By ~ 14

Author(s):

Moushimi Amaya ◽

Taryn Brooks-Faulconer ◽

Tyler Lark ◽

Forrest Keck ◽

Charles Bailey ◽

...

Keyword(s):

Venezuelan Equine Encephalitis Virus ◽

Encephalitis Virus ◽

Structural Protein ◽

Venezuelan Equine Encephalitis ◽

Rna Helicases ◽

Equine Encephalitis Virus ◽

Infected Cells

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The SD1 Subdomain of Venezuelan Equine Encephalitis Virus Capsid Protein Plays a Critical Role in Nucleocapsid and Particle Assembly

Journal of Virology ◽

10.1128/jvi.02680-15 ◽

2015 ◽

Vol 90 (4) ◽

pp. 2008-2020 ◽

Cited By ~ 3

Author(s):

Josephine M. Reynaud ◽

Valeria Lulla ◽

Dal Young Kim ◽

Elena I. Frolova ◽

Ilya Frolov

Keyword(s):

Capsid Protein ◽

Driving Forces ◽

Critical Role ◽

Venezuelan Equine Encephalitis Virus ◽

Encephalitis Virus ◽

Venezuelan Equine Encephalitis ◽

Particle Assembly ◽

Equine Encephalitis Virus ◽

Amino Terminal ◽

Virus Capsid Protein

ABSTRACTVenezuelan equine encephalitis virus (VEEV) is an important human and animal pathogen, for which no safe and efficient vaccines or therapeutic means have been developed. Viral particle assembly and budding processes represent potential targets for therapeutic intervention. However, our understanding of the mechanistic process of VEEV assembly, RNA encapsidation, and the roles of different capsid-specific domains in these events remain to be described. The results of this new study demonstrate that the very amino-terminal VEEV capsid-specific subdomain SD1 is a critical player in the particle assembly process. It functions in a virus-specific mode, and its deletion, mutation, or replacement by the same subdomain derived from other alphaviruses has strong negative effects on infectious virus release. VEEV variants with mutated SD1 accumulate adaptive mutations in both SD1 and SD2, which result in a more efficiently replicating phenotype. Moreover, efficient nucleocapsid and particle assembly proceeds only when the two subdomains, SD1 and SD2, are derived from the same alphavirus. These two subdomains together appear to form the central core of VEEV nucleocapsids, and their interaction is one of the driving forces of virion assembly and budding. The similar domain structures of alphavirus capsid proteins suggest that this new knowledge can be applied to other alphaviruses.IMPORTANCEAlphaviruses are a group of human and animal pathogens which cause periodic outbreaks of highly debilitating diseases. Despite significant progress made in understanding the overall structure of alphavirus and VEEV virions, and glycoprotein spikes in particular, the mechanistic process of nucleocapsid assembly, RNA encapsidation, and the roles of different capsid-specific domains in these processes remain to be described. Our new data demonstrate that the very amino-terminal subdomain of Venezuelan equine encephalitis virus capsid protein, SD1, plays a critical role in the nucleocapsid assembly. It functions synergistically with the following SD2 (helix I) and appears to form a core in the center of nucleocapsid. The core formation is one of the driving forces of alphavirus particle assembly.

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Resveratrol Inhibits Venezuelan Equine Encephalitis Virus Infection by Interfering with the AKT/GSK Pathway

Plants ◽

10.3390/plants10020346 ◽

2021 ◽

Vol 10 (2) ◽

pp. 346

Author(s):

Caitlin W. Lehman ◽

Kylene Kehn-Hall ◽

Megha Aggarwal ◽

Nicole R. Bracci ◽

Han-Chi Pan ◽

...

Keyword(s):

Antiviral Activity ◽

Fluorescent Protein ◽

Glycogen Synthase ◽

Venezuelan Equine Encephalitis Virus ◽

Encephalitis Virus ◽

Host Cells ◽

Dynamics Simulation ◽

Luciferase Reporter ◽

Venezuelan Equine Encephalitis ◽

Equine Encephalitis Virus

The host proteins Protein Kinase B (AKT) and glycogen synthase kinase-3 (GSK-3) are associated with multiple neurodegenerative disorders. They are also important for the replication of Venezuelan equine encephalitis virus (VEEV), thereby making the AKT/GSK-3 pathway an attractive target for developing anti-VEEV therapeutics. Resveratrol, a natural phytochemical, has been shown to substantially inhibit the AKT pathway. Therefore, we attempted to explore whether it exerts any antiviral activity against VEEV. In this study, we utilized green fluorescent protein (GFP)- and luciferase-encoding recombinant VEEV to determine the cytotoxicity and antiviral efficacy via luciferase reporter assays, flow cytometry, and immunofluorescent assays. Our results indicate that resveratrol treatment is capable of inhibiting VEEV replication, resulting in increased viability of Vero and U87MG cells as well as reduced virion production and viral RNA contents within host cells for at least 48 h with a single treatment. Furthermore, the suppression of apoptotic signaling adaptors, caspase-3, caspase-7, and annexin V may also be implicated in resveratrol-mediated antiviral activity. We found that decreased phosphorylation of the AKT/GSK-3 pathway, mediated by resveratrol, can be triggered during the early stages of VEEV infection, suggesting that resveratrol disrupts the viral replication cycle and consequently promotes cell survival. Finally, molecular docking and dynamics simulation studies revealed that resveratrol can directly bind to VEEV glycoproteins, which may interfere with virus attachment and entry. In conclusion, our results suggest that resveratrol exerts inhibitory activity against VEEV infection and upon further modification could be a useful compound to study in neuroprotective research and veterinary sciences.

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