Epitope tagging: a monoclonal antibody specific for recombinant fusion proteins in plants.

The easy identification of a recombinant protein in plant material becomes increasingly relevant as more transgenic plants are used for research and commercial applications. Tagging recombinant proteins with a small peptide (epitope) can perform such a task. However, available epitope antibodies will also cross-react with endogenous plant proteins at a level that may be unacceptable. Here we describe the new epitope antibody AcV5. Whether it is attached to the carbooxyl terminal end of enhanced green fluorescent protein (EGFP) or the Bacillus thuringiensis endotoxin Cry3A, these proteins remain functional. In addition, using less than 250 pg AcV5-tagged EGFP produces a strong signal on Western blots with no cross-reactivity of proteins from a broad range of plants of agronomic importance.