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The ORF7b protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is expressed in virus-infected cells and incorporated into SARS-CoV particles

Identifieur interne : 000604 ( PascalFrancis/Curation ); précédent : 000603; suivant : 000605

The ORF7b protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is expressed in virus-infected cells and incorporated into SARS-CoV particles

Auteurs : Scott R. Schaecher [États-Unis] ; Jason M. Mackenzie [Australie] ; Andrew Pekosz [États-Unis]

Source :

RBID : Pascal:07-0182090

Descripteurs français

English descriptors

Abstract

Coronavirus replication is facilitated by a number of highly conserved viral proteins. The viruses also encode accessory genes, which are virus group specific and believed to play roles in virus replication and pathogenesis in vivo. Of the eight putative accessory proteins encoded by the severe acute respiratory distress syndrome associated coronavirus (SARS-CoV), only two-open reading frame 3a (ORF3a) and ORF7a-have been identified in virus-infected cells to date. The ORF7b protein is a putative viral accessory protein encoded on subgenomic (sg) RNA 7. The ORF7b initiation codon overlaps the ORF7a stop codon in a-1 shifted ORF. We demonstrate that the ORF7b protein is expressed in virus-infected cell lysates and from a cDNA encoding the gene 7 coding region, indicating that the sgRNA7 is bicistronic. The translation of ORF7b appears to be mediated by ribosome leaky scanning, and the protein has biochemical properties consistent with that of an integral membrane protein. ORF7b localizes to the Golgi compartment and is incorporated into SARS-CoV particles. We therefore conclude that the ORF7b protein is not only an accessory protein but a structural component of the SARS-CoV virion.
pA  
A01 01  1    @0 0022-538X
A03   1    @0 J. virol.
A05       @2 81
A06       @2 2
A08 01  1  ENG  @1 The ORF7b protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is expressed in virus-infected cells and incorporated into SARS-CoV particles
A11 01  1    @1 SCHAECHER (Scott R.)
A11 02  1    @1 MACKENZIE (Jason M.)
A11 03  1    @1 PEKOSZ (Andrew)
A14 01      @1 Departments of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Ave @2 St. Louis, Missouri 63110-1093 @3 USA @Z 1 aut. @Z 3 aut.
A14 02      @1 School of Molecular and Microbial Sciences, University of Queensland @2 Brisbane, Queensland, 4072 @3 AUS @Z 2 aut.
A14 03      @1 Department of Pathology and Immunology, Washington University School of Medicine, 660 S. Euclid Ave @2 St. Louis, Missouri 63110-1093 @3 USA @Z 3 aut.
A20       @1 718-731
A21       @1 2007
A23 01      @0 ENG
A43 01      @1 INIST @2 13592 @5 354000159387240290
A44       @0 0000 @1 © 2007 INIST-CNRS. All rights reserved.
A45       @0 89 ref.
A47 01  1    @0 07-0182090
A60       @1 P
A61       @0 A
A64 01  1    @0 Journal of virology
A66 01      @0 USA
C01 01    ENG  @0 Coronavirus replication is facilitated by a number of highly conserved viral proteins. The viruses also encode accessory genes, which are virus group specific and believed to play roles in virus replication and pathogenesis in vivo. Of the eight putative accessory proteins encoded by the severe acute respiratory distress syndrome associated coronavirus (SARS-CoV), only two-open reading frame 3a (ORF3a) and ORF7a-have been identified in virus-infected cells to date. The ORF7b protein is a putative viral accessory protein encoded on subgenomic (sg) RNA 7. The ORF7b initiation codon overlaps the ORF7a stop codon in a-1 shifted ORF. We demonstrate that the ORF7b protein is expressed in virus-infected cell lysates and from a cDNA encoding the gene 7 coding region, indicating that the sgRNA7 is bicistronic. The translation of ORF7b appears to be mediated by ribosome leaky scanning, and the protein has biochemical properties consistent with that of an integral membrane protein. ORF7b localizes to the Golgi compartment and is incorporated into SARS-CoV particles. We therefore conclude that the ORF7b protein is not only an accessory protein but a structural component of the SARS-CoV virion.
C02 01  X    @0 002A05C10
C03 01  X  FRE  @0 Virus syndrome respiratoire aigu sévère @2 NW @5 01
C03 01  X  ENG  @0 Severe acute respiratory syndrome virus @2 NW @5 01
C03 01  X  SPA  @0 Severe acute respiratory syndrome virus @2 NW @5 01
C03 02  X  FRE  @0 Protéine @5 05
C03 02  X  ENG  @0 Protein @5 05
C03 02  X  SPA  @0 Proteína @5 05
C03 03  X  FRE  @0 Cellule infectée @5 06
C03 03  X  ENG  @0 Infected cell @5 06
C03 03  X  SPA  @0 Célula infectada @5 06
C03 04  X  FRE  @0 Virologie @5 07
C03 04  X  ENG  @0 Virology @5 07
C03 04  X  SPA  @0 Virología @5 07
C03 05  X  FRE  @0 Syndrome respiratoire aigu sévère @2 NM @5 14
C03 05  X  ENG  @0 Severe acute respiratory syndrome @2 NM @5 14
C03 05  X  SPA  @0 Síndrome respiratorio agudo severo @2 NM @5 14
C07 01  X  FRE  @0 Coronavirus @2 NW
C07 01  X  ENG  @0 Coronavirus @2 NW
C07 01  X  SPA  @0 Coronavirus @2 NW
C07 02  X  FRE  @0 Coronaviridae @2 NW
C07 02  X  ENG  @0 Coronaviridae @2 NW
C07 02  X  SPA  @0 Coronaviridae @2 NW
C07 03  X  FRE  @0 Nidovirales @2 NW
C07 03  X  ENG  @0 Nidovirales @2 NW
C07 03  X  SPA  @0 Nidovirales @2 NW
C07 04  X  FRE  @0 Virus @2 NW
C07 04  X  ENG  @0 Virus @2 NW
C07 04  X  SPA  @0 Virus @2 NW
C07 05  X  FRE  @0 Appareil respiratoire pathologie @5 13
C07 05  X  ENG  @0 Respiratory disease @5 13
C07 05  X  SPA  @0 Aparato respiratorio patología @5 13
C07 06  X  FRE  @0 Virose
C07 06  X  ENG  @0 Viral disease
C07 06  X  SPA  @0 Virosis
C07 07  X  FRE  @0 Infection
C07 07  X  ENG  @0 Infection
C07 07  X  SPA  @0 Infección
C07 08  X  FRE  @0 Poumon pathologie @5 16
C07 08  X  ENG  @0 Lung disease @5 16
C07 08  X  SPA  @0 Pulmón patología @5 16
N21       @1 122
N44 01      @1 OTO
N82       @1 OTO

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Pascal:07-0182090

Le document en format XML

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   |texte=   The ORF7b protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is expressed in virus-infected cells and incorporated into SARS-CoV particles
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