An elite <i>γ‐gliadin</i> allele improves end‐use quality in wheat
Dan Liu, Huaimao Yang, Zhaoheng Zhang, Qian Chen, Weilong Guo, Vincenzo Rossi, Mingming Xin, Jinkun Du, Zhaorong Hu, Jie Liu, Huiru Peng, Zhongfu Ni, Qixin Sun, Yingyin Yao
Abstract
Gluten is composed of glutenins and gliadins and determines the viscoelastic properties of dough and end-use quality in wheat (Triticum aestivum L.). Gliadins are important for wheat end-use traits, but the contribution of individual gliadin genes is unclear, since gliadins are encoded by a complex, multigenic family, including many pseudogenes. We used CRISPR/Cas9-mediated gene editing and map-based cloning to investigate the contribution of the γ-gliadin genes annotated in the wheat cultivar 'Fielder', showing that Gli-γ1-1D and Gli-γ2-1B account for most of the γ-gliadin accumulation. The impaired activity of only two γ-gliadin genes in knockout mutants improved end-use quality and reduced gluten epitopes associated with celiac disease (CD). Furthermore, we identified an elite haplotype of Gli-γ1-1D linked to higher end-use quality in a wheat germplasm collection and developed a molecular marker for this allele for marker-assisted selection. Our findings provide information and tools for biotechnology-based and classical breeding programs aimed at improving wheat end-use quality.