IDENTIFICATION OF A 37 KDA PLANT PROTEIN THAT INTERACTS WITH THE TURNIP MOSAIC POTYVIRUS CAPSID PROTEIN USING ANTI-IDIOTYPIC-ANTIBODIES

Experimental data are provided for the presence of a plant protein tha t interacts with the capsid protein (CP) of turnip mosaic potyvirus (T uMV). The receptor-like protein was identified by exploiting the molec ular mimicry potential of anti-idiotypic antibodies. A single-chain Fv molecule derived from the monoclonal antibody 7A (Mab-7A), which reco gnizes the CP of TuMV, was produced in Escherichia coli and the recomb inant protein was used to raise rabbit antibodies. The immune serum re acted with Mab-7A but not with a monoclonal antibody of the same isoty pe, indicating that anti-idiotypic antibodies were produced. These ant i-idiotypic antibodies recognized a 37 kDa protein from Lactuca saliva . Complex formation between the anti-idiotypic antibodies and the plan t protein was inhibited by the CP of TuMV which indicates that the pla nt protein interacts with the viral protein. The 37 kDa protein was lo calized in chloroplasts and was detected in other plant species.