Two-dimensional analysis of gliadin proteins associated with quality in durum wheat: chromosomal location of genes for their synthesis.

Two-dimensional electrophoresis was used to fractionate the gliadin proteins from the endosperm of durum wheat. The increased resolution of the system, as compared with single-dimensional analysis, accentuated the heterogeneity of the proteins. This resolution, coupled with the use of aneuploid lines of the cultivar 'Langdon', permitted identification of the chromosomes controlling synthesis of the major protein components. Homoeologous Group 1 chromosomes controlled omega- and gamma-gliadin synthesis and the Group 6 chromosomes 6A and 6B controlled alpha- and beta-gliadins. Chromosome 1B was primarily responsible for the two groups of protein-polypeptides associated with strong or weak gluten characteristics of durum wheat. However, some of these proteins were controlled by chromosome 1A. In the beta-gliadin region several hybrid bands, whose chromosomal control was not identified by electrophoresis alone, were specified primarily by genes on chromosome 6B, although chromosome 6A was also involved. Control of some other hybrid bands could not be determined. Chromosomes in Groups 2, 3, 4, 5 and 7 were not implicated in the synthesis of the gliadin proteins of durum wheat.