Molecular characterization of the polypeptides of an aquareovirus

Aquareoviruses are non-enveloped with a double-layered capsid and contains a genome composed of 11 segments of double-stranded (ds) RNA. These viruses grow very slowly in tissue culture and there is a need for a rapid and sensitive method for detection of aquareovirus infections. In the present study, a nucleic acid hybridization assay was developed to rapidly detect small quantities of aquareovirus RNAs in infected cells and organs. This assay allowed us to detect aquareovirus infections in tissue culture before cytopathic effect was evident.; 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. Seven structural and five nonstructural proteins were identified by SDS-PAGE. Segments 1--10 of the SBR virus genome encoded one protein, while segment 11 encoded two proteins. The major outer capsid protein, VP7 was found to be glycosylated with short oligosaccharide chains.; The relative mobility of the 11 dsRNA genomic segments of twenty-two isolates were compared by polyacrylamide gel electrophoresis. Analysis of the migration patterns of the 11 dsRNA genome segments showed distinct electrophoreotypes. Using reciprocal RNA-RNA dot blot hybridization, a new sixth genetic group of aquareovirus (genogroup F) was identified.; The nucleotide and deduced amino acid sequences of genome segment 11 encoding two nonstructural polypeptides of an aquareovirus strain SBR have been determined. Deletion studies indicated that both polypeptides are being produced form the same open reading frame but at two initiation sites.