Assembly of Amsacta moorei entomopoxvirus spheroidin into spheroids following synthesis in insect cells using a baculovirus vector.
The gene encoding the major occlusion body protein, spheroidin, of Amsacta moorei entomopoxvirus (AmEPV) was introduced into a baculovirus vector under control of the polyhedrin gene promoter. A recombinant virus produced large, ovoid occlusion body-like structures in both Spodoptera frugiperda and Trichoplusia ni cells. These structures resembled the spheroids found in AmEPV-infected Lymantria dispar cells, except they were devoid of virus particles and were not surrounded by a membrane- or envelope-like structure. These results were confirmed by immunofluoresence microscopy and Western blotting using a specific antipeptide antibody to spheroidin, and suggest that the supramolecular assembly of spheroids is not dependent on other EPV-encoded gene products. Transmission electron microscopy and subcellular fractionation experiments revealed that the spheroid-like structures were assembled in both the nucleus and cytoplasm of the recombinant virus-infected cells. This contrasts with the solely cytoplasmic localization found in AmEPV-infected cells.
Marlow
S A
SA
School of Biological and Molecular Sciences, Gipsy Lane Campus, Oxford Brookes University, UK.
Wilson
L E
LE
Lawrie
A M
AM
Wilkinson
N
N
King
L A
LA
D000818:Animals; D016367:Baculoviridae; D015153:Blotting, Western; D002478:Cells, Cultured; D019084:Fluorescent Antibody Technique, Indirect; D007313:Insecta; D008854:Microscopy, Electron; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins; D018411:Spodoptera; D013347:Subcellular Fractions; D014764:Viral Proteins / Q000502:physiology* / Q000648:ultrastructure; D015678:Viral Structural Proteins; D019065:Virus Assembly
D011994:Recombinant Proteins; D014764:Viral Proteins; D015678:Viral Structural Proteins; C063744:spheroidin protein, Entomopoxvirus