Proteomic analysis of wheat recombinant inbred lines: Variations in prolamin and dough rheology
Résumé
To investigate the impact of the 1BL.1RS translocation on dough strength and to understand how 1BL.1RS genotypes may overcome the loss of Glu-B3 and Gli-B1, proteomic profiles of 16 doubled haploid (DH) lines of similar glutenin composition but of different strength, as measured by Chopin's alveograph, were compared. The results showed that 32 spots, mainly prolamins, were differentially expressed and that five others were specific to high-strength DH lines. The identification and quantification of the prolamin fractions on the two-dimensional (2D) electrophoresis gels demonstrated that the high-molecular weight glutenin sub-unit (HMW-GS) were up-regulated by 25% in 1BL.1RS DH lines, even though the corresponding genes were not located on the missing 1BS chromosome. The γ-gliadins were also up-regulated (by 36%) in such lines to counterbalance, to some extent, the loss of LMW-GS of Glu-B3. The polymeric prolamin fractions also accumulated in high-tenacity lines and decreased in high-extensibility lines confirming the role of the inter-chain disulfide bonds in resistance to deformation. In contrast, the monomeric fraction of α-gliadin favored extensibility and decreased tenacity by increasing the accumulation (+12%) of α-gliadins in high-extensibility lines; the Gli-A1 allele of the parent Toronit was found to be more abundant when compared to the Gli-A1 allele of parent 211.12014.