Characterization of Gliadins Using Aneuploid Lines in Chinese Spring Wheat

Gluten comprises glutenins and gliadins and plays an important role in the property of flour. Genes encoding gluten proteins consist of multigene families in the wheat genome. Gliadins are further classified into α/β, γ, and ω-gliadins; α/β-gliadins are encoded by an exceptionally large number of multigenes. Furthermore, certain α/β-gliadins cause celiac disease (CD). To characterize each gliadin, 2D-PAGE profiles of gliadins extracted from mature seeds were compared among Chinese Spring wheat (CS) and its aneuploid lines. Gliadins were separated into 70 spots and their chromosomal location of genes was determined. Interestingly, specific α/β-gliadins derived from the 6D chromosome were partially lost in the tetrasomic 2A lines. Western analysis showed that α/β-gliadins harboring CD epitopes were specifically suppressed in these lines. Gene expression of α/β-gliadins was measured by quantitative RT-PCR. The suppression occurred in mRNA accumulation during seed development. These results suggested that the 2A chromosome of CS suppresses the gene expression of specific α/β-gliadins. The information of 70 characterized gliadin spots and their regulation should be useful for breeding hypoallergenic wheat.