Allelic variation of the HMW glutenin subunits in Aegilops tauschii accessions detected by sodium dodecyl sulphate (SDS-PAGE), acid polyacrylamide gel (A-PAGE) and capillary electrophoresis

Abstract

Variability of high molecular weight glutenin subunits (HMW-GS) was studied in198 accessions of Ae. Tauschii (2n=2x=14, DD) by sodium dodecyl sulphate(SDS-PAGE) and acid polyacrylamide gel electrophoresis (A-PAGE) and capillary electrophoresis (CE). A high allelic variation of HMW-GS, including some novel x- and y-type subunits and variable subunit combinations were observed. One accession(TD159) showed a x-type null form. The results by A-PAGE analysis revealed that the subunits Dx5 t and Dy10 t encoded by Glu-D t 1 locus in Ae. tauschii were different in relative mobilities in comparison with the subunits Dx5 and Dy10 found in bread wheats, whereas they had the same mobilities, respectively, when separated by SDS-PAGE. The higher resolution of Ae. tauschii HMW-GS separated by CE method showed two clear peaks in accordance with x- and y-type subunits, respectively,except the accession TD151 which possessed only subunit Dy12.1*t. The electro elution time of the x-type and y-type subunits were about 13–14 and 7–8minutes, respectively. Characterization of wheat HMW-GS was facilitated by using CE which provides high resolution and increases the speed of analysis in conjunction with the traditional gel electrophoretic methods. A total of 42HMW-GS alleles were identified, among which were several alleles not presently detected in bread wheats. Hence Ae. tauschii is potentially a valuable genetic resource for quality improvement of bread wheat.