Detection of Potyviral Nuclear Inclusion b Proteins by Monoclonal Antibodies Raised to Synthetic Peptides

Potyviral nuclear inclusion b protein (NIb), the RNA-dependent RNA polymerase, contains three highly conserved regions. Peptides corresponding to these regions were synthesised and used for immunisation. A panel of monoclonal antibodies was obtained. Most of the MAbs reacted with the peptides and a recombinant NIb of PVY in PTA-ELISA. Two of them specifically detected native NIb of potato A, potato V, potato Y, plum pox and turnip mosaic potyviruses in extracts of infected plants in Western blots. Time course experiments revealed that NIb protein can be first detected on the fifth day after infection.