Chromosomal control of wheat gliadin protein epitopes: analysis with specific monoclonal antibodies

The genetic relationships between small clusters of monomeric alcohol-soluble wheat (Triticum aestivum L.) grain storage proteins (gliadins) were studied using a panel of monoclonal antibodies and immunoblotting, ELISA, and RIA methods. Use of Chinese Spring nullisomic-tetrasomic lines showed that several narrow-specificity antibodies bound specifically to gliadins encoded by genes located on a single chromosome. In at least one case, antibodies bound to genetic "blocks" of gliadins, indicating that these block members have structural homology. However, often not all gliadins of a block were recognized by an antibody. For broad-specificity antibodies and some narrow-specificity antibodies, structural genes on several chromosomes were important. Studies with several primitive wheat species indicated that, while antibodies usually bound gliadins from the same genome in bread and primitive wheats, antibodies sometimes bound proteins of quite differing mobilities in the two wheat types. Use of antibodies to identify gliadin blocks is simpler than block analysis based on performing crosses, and should be of value in monitoring genotype/end-use quality relationships.