N-glycosylated polypeptides synthesized in the early phase of AcNPV infected insect cells.

Infected cell specific polypeptides (ICSP) in Autographa californica nuclear polyhedrosis virus (AcNPV) infected Spodoptera frugiperda cell line, Sf9, were radiolabelled with [14C] mannose and the labelled proteins were monitored at various time intervals. A major glycoprotein of molecular size of 64 kDa appears as early as 3h post infection (p.i.) which peaks at 12h p.i., but in presence of tunicamycin this protein is not labelled. Two other glycoproteins of molecular size 67 kDa and 63 kDa appear at 12h post infection. The glycosylation of these and eight other cellular proteins is also inhibited by tunicamycin. AcNPV propagated in tunicamycin treated Sf9 cells was found to cause delayed infectivity.