Expression and assembly of the potato virus Y (PVY) coat protein (CP) in Escherichia coli cells

A clone harboring the full-length cDNA of potato virus Y in a lambda-DASH vector under the control of a T7 promoter was introduced into Escherichia coli carrying the T7-RNA-polymerase gene on a plasmid. The viral coat protein was expressed and the product was of the same size as the corresponding mature protein in infected plants. Immunoelectronmicroscopy of transfected cell extracts revealed virus-like particles, indicating that the proteins involved in its processing and the viral coat protein retained their native activity.