EXPRESSION OF POTYVIRUS PROTEINS IN INSECT CELLS INFECTED WITH A RECOMBINANT BACULOVIRUS

The N-terminal portion (P1-HC-Pro-P3) of the tobacco vein mottling vir us (TVMV) polyprotein was expressed in insect cells and larvae by a re combinant baculovirus. The proteases necessary to process this TVMV po lyprotein fragment were active in insect cells, since mature P1. HC-Pr o and P3 proteins were detected by specific antisera in Western blots. Antisera to P1, HC-Pro and P3 also recognized polypeptides with appar ent M(r) values predicted for the intermediate processing products of the polyprotein fragment. The results of this study indicate that the autocatalytic processing of TVMV HC-Pro from the polyprotein is suppor ted by insect cells. Helper component activity in extracts of cells in fected with recombinant baculovirus was not detected by aphid transmis sion assay.