Previous Article | Next Article 
Journal of Virology, April 2007, p. 3866-3876, Vol. 81, No. 8
0022-538X/07/$08.00+0 doi:10.1128/JVI.02075-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.
Capsid Protein of Eastern Equine Encephalitis Virus Inhibits Host Cell Gene Expression
Patricia V. Aguilar,1
Scott C. Weaver,2,3 and
Christopher F. Basler1*
Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029,1
Center for Biodefense and Emerging Infectious Diseases,2
Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555-06093
Received 21 September 2006/
Accepted 18 January 2007
Eastern equine encephalitis virus (EEEV) causes sporadic but often severe cases of human and equine neurological disease in North America. To determine how EEEV may evade innate immune responses, we screened individual EEEV proteins for the ability to rescue the growth of a Newcastle disease virus expressing green fluorescent protein (NDV-GFP) from the antiviral effects of interferon (IFN). Only expression of the EEEV capsid facilitated NDV-GFP replication. Inhibition of the antiviral effects of IFN by the capsid appears to occur through a general inhibition of cellular gene expression. For example, the capsid inhibited the expression of several reporter genes under the control of RNA polymerase II promoters. In contrast, capsid did not inhibit expression from a T7 RNA polymerase promoter construct, suggesting that the inhibition of gene expression is specific and is not a simple manifestation of toxicity. The inhibition correlated both with capsid-induced phosphorylation of eukaryotic initiation factor 2 alpha and with capsid-mediated inhibition of cellular mRNA accumulation. Mapping analysis identified the N terminus as the region important for the inhibition of host gene expression, suggesting that this inhibition is independent of capsid protease activity. Finally, when cell lines containing EEEV replicons encoding capsid were selected, replicons consistently acquired mutations that deleted all or part of the capsid, for example, amino acids 18 to 135. Given that the amino terminus of the capsid is required to inhibit host cell gene expression, these data suggest that capsid expression from the replicons is ultimately toxic to host cells, presumably because of its ability to inhibit gene expression.
* Corresponding author. Mailing address: Department of Microbiology, Box 1124, Mount Sinai School of Medicine, 1 Gustave L. Levy Place, New York, NY 10029. Phone: (212) 241-4847. Fax: (212) 534-1684. E-mail:
chris.basler{at}mssm.edu
Published ahead of print on 31 January 2007.
Journal of Virology, April 2007, p. 3866-3876, Vol. 81, No. 8
0022-538X/07/$08.00+0 doi:10.1128/JVI.02075-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Simmons, J. D., White, L. J., Morrison, T. E., Montgomery, S. A., Whitmore, A. C., Johnston, R. E., Heise, M. T.
(2009). Venezuelan Equine Encephalitis Virus Disrupts STAT1 Signaling by Distinct Mechanisms Independent of Host Shutoff. J. Virol.
83: 10571-10581
[Abstract]
[Full Text]
-
Yin, J., Gardner, C. L., Burke, C. W., Ryman, K. D., Klimstra, W. B.
(2009). Similarities and Differences in Antagonism of Neuron Alpha/Beta Interferon Responses by Venezuelan Equine Encephalitis and Sindbis Alphaviruses. J. Virol.
83: 10036-10047
[Abstract]
[Full Text]
-
Attarzadeh-Yazdi, G., Fragkoudis, R., Chi, Y., Siu, R. W. C., Ulper, L., Barry, G., Rodriguez-Andres, J., Nash, A. A., Bouloy, M., Merits, A., Fazakerley, J. K., Kohl, A.
(2009). Cell-to-Cell Spread of the RNA Interference Response Suppresses Semliki Forest Virus (SFV) Infection of Mosquito Cell Cultures and Cannot Be Antagonized by SFV. J. Virol.
83: 5735-5748
[Abstract]
[Full Text]
-
Gardner, C. L., Burke, C. W., Tesfay, M. Z., Glass, P. J., Klimstra, W. B., Ryman, K. D.
(2008). Eastern and Venezuelan Equine Encephalitis Viruses Differ in Their Ability To Infect Dendritic Cells and Macrophages: Impact of Altered Cell Tropism on Pathogenesis. J. Virol.
82: 10634-10646
[Abstract]
[Full Text]
-
Aguilar, P. V., Leung, L. W., Wang, E., Weaver, S. C., Basler, C. F.
(2008). A Five-Amino-Acid Deletion of the Eastern Equine Encephalitis Virus Capsid Protein Attenuates Replication in Mammalian Systems but Not in Mosquito Cells. J. Virol.
82: 6972-6983
[Abstract]
[Full Text]
-
Aguilar, P. V., Adams, A. P., Wang, E., Kang, W., Carrara, A.-S., Anishchenko, M., Frolov, I., Weaver, S. C.
(2008). Structural and Nonstructural Protein Genome Regions of Eastern Equine Encephalitis Virus Are Determinants of Interferon Sensitivity and Murine Virulence. J. Virol.
82: 4920-4930
[Abstract]
[Full Text]
-
Ilkow, C. S., Mancinelli, V., Beatch, M. D., Hobman, T. C.
(2008). Rubella Virus Capsid Protein Interacts with Poly(A)-Binding Protein and Inhibits Translation. J. Virol.
82: 4284-4294
[Abstract]
[Full Text]
-
Atasheva, S., Garmashova, N., Frolov, I., Frolova, E.
(2008). Venezuelan Equine Encephalitis Virus Capsid Protein Inhibits Nuclear Import in Mammalian but Not in Mosquito Cells. J. Virol.
82: 4028-4041
[Abstract]
[Full Text]
-
Randall, R. E., Goodbourn, S.
(2008). Interferons and viruses: an interplay between induction, signalling, antiviral responses and virus countermeasures. J. Gen. Virol.
89: 1-47
[Abstract]
[Full Text]
-
Garmashova, N., Atasheva, S., Kang, W., Weaver, S. C., Frolova, E., Frolov, I.
(2007). Analysis of Venezuelan Equine Encephalitis Virus Capsid Protein Function in the Inhibition of Cellular Transcription. J. Virol.
81: 13552-13565
[Abstract]
[Full Text]