1887

Abstract

A combined qualitative and quantitative approach has been used to examine the role of virus inclusion bodies (VIBs) in the morphogenesis of bluetongue virus (BTV). VIBs were detected as early as 4 h post-infection (p.i.), and their number and profile areas increased significantly between 12 and 16 h, and 20 and 28 h p.i. respectively. Core- and virus-like particles were found within and at the periphery of the VIB matrix, respectively, and their numerical density (number per area of VIB matrix) decreased during the course of infection whereas the numerical density of virus particles in the cytoplasm increased. Virus-like particles had a diameter of 57 ± 8 nm and core-like particles appeared to fall into two size ranges, 32 ± 3 nm and 38 ± 3 nm in diameter. Both pre- and post-embedding immunoelectron microscopy procedures were used to localize BTV structural and non-structural proteins within the VIBs. The VIB matrix was labelled with antibodies to structural proteins VP5 and VP7 and non-structural proteins NS1 and NS2. Cores within VIBs contained proteins VP5, VP7 and NS1 but not VP2. Virus-like particles at the periphery of VIBs contained VP2, VP5, VP7 and NS1. The results suggest that BTV particles are synthesized, assembled and released from the perimeter of VIBs and not from within the matrix. Cores embedded in the VIBs are likely to have been trapped there during expansion of the matrix during replication.

Loading

Article metrics loading...

/content/journal/jgv/10.1099/0022-1317-74-3-525
1993-03-01
2021-10-27
Loading full text...

Full text loading...

/deliver/fulltext/jgv/74/3/JV0740030525.html?itemId=/content/journal/jgv/10.1099/0022-1317-74-3-525&mimeType=html&fmt=ahah

References

  1. Arnold J. R., Boor P. J. 1986; Improved transmission electron microscopy (TEM) of cultured cells through a “floating sheet” method. Journal of Ultrastructural and Molecular Structure Research 94:30–36
    [Google Scholar]
  2. Bowne J. G., Jochim M. M. 1967; Cytopathologic changes and development of inclusion bodies in cultured cells infected with bluetongue virus. American Journal of Veterinary Research 28:1091–1105
    [Google Scholar]
  3. Eaton B. T., Hyatt A. D., White J. R. 1987; Association of bluetongue virus with the cytoskeleton. Virology 157:107–116
    [Google Scholar]
  4. Eaton B. T., Hyatt A. D., White J. R. 1988; Localization of the nonstructural protein NS1 in bluetongue virus-infected cells and its presence in virus particles. Virology 163:527–537
    [Google Scholar]
  5. Eaton B. T., Hyatt A. D., Brookes S. M. 1990; The replication of bluetongue virus. Current Topics in Microbiology and Immunology 162:89–118
    [Google Scholar]
  6. Hewat E. A., Booth T. F., Loudon P. T, Roy P. 1992a; Threedimensional reconstruction of baculovirus expressed bluetongue virus core-like particles by cryo-electron microscopy. Virology 189:10–20
    [Google Scholar]
  7. Hewat B. T., Booth T. F., Roy P. 1992b; Structure of bluetongue virus particles by cryo-electron microscopy. Journal of Structural Biology 109:61–69
    [Google Scholar]
  8. Huismans H., van Dijk A. A., Els H. J. 1987; Uncoating of parental bluetongue virus to core and subcore particles in infected L cells. Virology 157:180–188
    [Google Scholar]
  9. Hyatt A. D. 1991; Immunogold labeling techniques. In Electron-microscopy in Biology: A Practical Approach. Edited by Harris R. Oxford: IRL Press;
    [Google Scholar]
  10. Hyatt A. D., Eaton B. T. 1988; Ultrastructural distribution of the major capsid proteins within bluetongue virus and infected cells. Journal of General Virology 69:805–815
    [Google Scholar]
  11. Hyatt A. D., Eaton B. T., Brookes S. M. 1989; The release of bluetongue virus from infected cells and their superinfection by progeny virus. Virology 173:21–34
    [Google Scholar]
  12. Hyatt A. D., Zhao Y., Roy P. 1992; Release of bluetongue viruslike particles from insect cells is mediated by BTV non-structural protein NS3/NS3A. Virology (in press)
    [Google Scholar]
  13. Lecatsas G. 1968; Electron microscope study of the formation of bluetongue virus. Onderstepoort Journal of Veterinary Research 35:139–150
    [Google Scholar]
  14. Loudon P. T., Roy P. 1991; Assembly of five bluetongue virus proteins expressed by recombinant baculoviruses : inclusion of the largest protein VP1 in the core and virus-like particles. Virology 180:798–802
    [Google Scholar]
  15. Pinto da Silva P., Parkinson C., Dwyer N. 1981; Freeze fracture cytochemistry: thin sections of cells and tissues after labelling of fracture faces. Journal of Histochemistry and Cytochemistry 29:917–928
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jgv/10.1099/0022-1317-74-3-525
Loading
/content/journal/jgv/10.1099/0022-1317-74-3-525
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error