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Title: Sorting of influenza A virus RNA genome segments after nuclear export

Abstract

The genome of the influenza A virus consists of eight different segments. These eight segments are thought to be sorted selectively in infected cells. However, the cellular compartment where segments are sorted is not known. We examined using temperature sensitive (ts) mutant viruses and cell fusion where segments are sorted in infected cells. Different cells were infected with different ts mutant viruses, and these cells were fused. In fused cells, genome segments are mixed only in the cytoplasm, because M1 prevents their re-import into the nucleus. We made a marker ts53 virus, which has silent mutations in given segments and determined the reassortment frequency on all segments using ts1 and marker ts53. In both co-infected and fused cells, all of marker ts53 segments and ts1 segments were incorporated into progeny virions in a random fashion. These results suggest that influenza virus genome segments are sorted after nuclear export.

Authors:
 [1];  [2]; ;  [1];  [3];  [1]
  1. Department of Infection Biology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8575 (Japan)
  2. (Japan)
  3. Laboratory of Molecular Biology of Infectious Agents, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521 (Japan)
Publication Date:
OSTI Identifier:
21357621
Resource Type:
Journal Article
Resource Relation:
Journal Name: Virology; Journal Volume: 401; Journal Issue: 2; Other Information: DOI: 10.1016/j.virol.2010.02.030; PII: S0042-6822(10)00152-2; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; COMPARTMENTS; CYTOPLASM; INFLUENZA VIRUSES; MUTANTS; MUTATIONS; PROGENY; RNA; SORTING; CELL CONSTITUENTS; MICROORGANISMS; NUCLEIC ACIDS; ORGANIC COMPOUNDS; PARASITES; VIRUSES

Citation Formats

Takizawa, Naoki, Laboratory of Molecular Biology of Infectious Agents, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Kumakura, Michiko, Takeuchi, Kaoru, Kobayashi, Nobuyuki, and Nagata, Kyosuke, E-mail: knagata@md.tsukuba.ac.j. Sorting of influenza A virus RNA genome segments after nuclear export. United States: N. p., 2010. Web. doi:10.1016/j.virol.2010.02.030.
Takizawa, Naoki, Laboratory of Molecular Biology of Infectious Agents, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Kumakura, Michiko, Takeuchi, Kaoru, Kobayashi, Nobuyuki, & Nagata, Kyosuke, E-mail: knagata@md.tsukuba.ac.j. Sorting of influenza A virus RNA genome segments after nuclear export. United States. doi:10.1016/j.virol.2010.02.030.
Takizawa, Naoki, Laboratory of Molecular Biology of Infectious Agents, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Kumakura, Michiko, Takeuchi, Kaoru, Kobayashi, Nobuyuki, and Nagata, Kyosuke, E-mail: knagata@md.tsukuba.ac.j. 2010. "Sorting of influenza A virus RNA genome segments after nuclear export". United States. doi:10.1016/j.virol.2010.02.030.
@article{osti_21357621,
title = {Sorting of influenza A virus RNA genome segments after nuclear export},
author = {Takizawa, Naoki and Laboratory of Molecular Biology of Infectious Agents, Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521 and Kumakura, Michiko and Takeuchi, Kaoru and Kobayashi, Nobuyuki and Nagata, Kyosuke, E-mail: knagata@md.tsukuba.ac.j},
abstractNote = {The genome of the influenza A virus consists of eight different segments. These eight segments are thought to be sorted selectively in infected cells. However, the cellular compartment where segments are sorted is not known. We examined using temperature sensitive (ts) mutant viruses and cell fusion where segments are sorted in infected cells. Different cells were infected with different ts mutant viruses, and these cells were fused. In fused cells, genome segments are mixed only in the cytoplasm, because M1 prevents their re-import into the nucleus. We made a marker ts53 virus, which has silent mutations in given segments and determined the reassortment frequency on all segments using ts1 and marker ts53. In both co-infected and fused cells, all of marker ts53 segments and ts1 segments were incorporated into progeny virions in a random fashion. These results suggest that influenza virus genome segments are sorted after nuclear export.},
doi = {10.1016/j.virol.2010.02.030},
journal = {Virology},
number = 2,
volume = 401,
place = {United States},
year = 2010,
month = 6
}
  • The NS1 protein of influenza viruses is a major virulence factor and exerts its function through interacting with viral/cellular RNAs and proteins. In this study, we identified heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) as an interacting partner of NS1 proteins by a proteomic method. Knockdown of hnRNP A2/B1 by small interfering RNA (siRNA) resulted in higher levels of NS vRNA, NS1 mRNA, and NS1 protein in the virus-infected cells. In addition, we demonstrated that hnRNP A2/B1 proteins are associated with NS1 and NS2 mRNAs and that knockdown of hnRNP A2/B1 promotes transport of NS1 mRNA from the nucleus to themore » cytoplasm in the infected cells. Lastly, we showed that knockdown of hnRNP A2/B1 leads to enhanced virus replication. Our results suggest that hnRNP A2/B1 plays an inhibitory role in the replication of influenza A virus in host cells potentially through suppressing NS1 RNA/protein levels and NS1 mRNA nucleocytoplasmic translocation. - Highlights: • Cellular protein hnRNP A2/B1 interacts with influenza viral protein NS1. • hnRNP A2/B1 suppresses the levels of NS1 protein, vRNA and mRNA in infected cells. • hnRNP A2/B1 protein is associated with NS1 and NS2 mRNAs. • hnRNP A2/B1 inhibits the nuclear export of NS1 mRNAs. • hnRNP A2/B1 inhibits influenza virus replication.« less
  • Three cloned segments that hybridize to a region of simian virus 40 (SV40) deoxyribonucleic acid including the origin of replication have been isolated from a monkey genomic library. The primary structure of one segment was previously reported. The authors report here the sequences of the other two segments and comparison of all three. The SV40-hybridizing region in each segment is limited to several hundred base pairs. All of the segments contain multiple and disconnected sequences homologous to the region of SV40 directly surrounding the viral replication origin. The number and arrangement of the homologous sequences is different in the threemore » segments. However, the segments have the following features in common: (i) each contains multiple copies of the sequence GGGCGGPuPu, which also appears six times near the origin of SV40; (ii) each contains several strong homologies to the central dyad symmetry of SV40; (iii) each contains a long internal repeat, as does the origin region of SV40. The three SV40-hybridizing segments are members of a larger family of genomic sequences that hybridize well to each other, but not necessarily to SV40.« less
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