Glycoproteins of Bovine Viral Diarrhoea-Mucosal Disease Virus in Infected Bovine Cells

Abstract

Summary Bovine cell cultures infected with bovine viral diarrhoea-mucosal disease (BVD) virus were radiolabelled with l-[35S]methionine or d-[2-3H]mannose followed by analysis of the labelled polypeptides by radioimmunoprecipitation and polyacrylamide gel electrophoresis in one and two dimensions. Six glycoproteins were detected in infected cells. Two abundant species had M r of 48K and 56K to 58K while the less abundant species had M r of 118K, 75K, 65K and 25K. When cells were radiolabelled with l-[35S]methionine in the presence of tunicamycin 56K to 58K migrated with apparent masses of 54K (a minor species) and 48K to 50K (the major molecular species) in PAGE. Endoglycosidase F digestion of virus-induced polypeptides caused a 4K to 6K reduction in the apparent molecular mass of 56K to 58K yielding a single 52K digested product, indicating that theheterogeneity of 56K to 58K was due to differences in the oligosaccharide moieties. Tunicamycin caused a drastic reduction in the yield of infectious virus indicating that the carbohydrate moieties serve a critical role in the infectious cycle of BVD virus.