Characterization of the polypeptides and determination of genome coding assignments of an aquareovirus.

Proteins of an aquareovirus isolated from striped bass (SBR strain) were examined. Twelve viral-specific proteins ranging in molecular weight from approximately 130 to 15 kDa were identified in infected cells. Purified virions and infected cell lysates were used to characterize the structural and nonstructural proteins of the virus. Seven structural and five nonstructural proteins were identified by SDS-PAGE. Cell-free translation of total SBR virion RNA in a rabbit reticulocyte system resulted in the synthesis of proteins which were both qualitatively and quantitatively very similar to those found in infected cells. Segments 1-10 of the SBR virus genome encoded one protein each, while segment 11 encoded two proteins. The coding assignments of all the purified genome segments were determined by in vitro translation and the in vitro synthesized proteins were found to be viral specific by immunoprecipitation. The major outer capsid protein, VP7, was found to be glycosylated. The electrophoretic mobility of VP7 in SDS-PAGE was not altered when untreated and deglycosylated proteins were compared, indicating the presence of short oligosaccharide chains.