Abstract

Avenin-like storage proteins affect the rheological properties and processing quality of common wheat. Triticum urartu, the A-genome donor of polyploid wheat, shows abundant variation in its glutenin subunits. In this study, the variability in avenin-like b genes was evaluated in 74 T. urartu accessions. High levels of polymorphism were demonstrated in the analyzed sequence, resulting in the discovery of 18 novel TuALPb7A alleles (TuALPb7A-A–TuALPb7A-R). There were nucleotide sequence differences in 18 locations, which, due to synonymous mutations, resulted in amino acid changes. The polymorphic sites were located in the N-terminus, repetitive region (Left), repetitive region (Right) and C-terminus domains. The position of some cysteine residues was different in T. urartu and Aegilops tauschii accessions. Phylogenetic analysis divided the avenin-like b (ALPb) genes into two groups. The ALPb-7A alleles, containing 18 TuALPb7As, were distributed in the first group, whereas the ALPb-4A alleles were present in another. Avenin-like proteins encoded by four alleles (TuALPb7A-G, TuALPb7A-O, TuALPb7A-K and TuALPb7A-C) were expressed on a large scale and purified to estimate the effect on dough mixing properties. Mixograph testing demonstrated that these proteins could improve the functional properties of dough, including the mixing time, peak dough resistance and breakdown in resistance. The avenin-like b genes hold rich genetic alleles in T. urartu, and can improve the functional properties of dough. The new favourable alleles discovered will provide breeding materials and a theoretical basis for wheat quality improvement.

摘要

类蛇毒蛋白存储蛋白会影响普通小麦的流变特性和加工质量。多倍体小麦的A基因组供体Triticum urartu的谷蛋白亚基显示出丰富的变异。在这项研究中，评估了74个urartu保藏号中avenven-like b基因 的变异性。在分析的序列中证明了高水平的多态性，从而发现了18个新的TuALPb7A等位基因（TuALPb7A-A – TuALPb7A-R）。在18个位置存在核苷酸序列差异，由于同义突变，导致氨基酸变化。多态性位点位于N端，重复区（左），重复区（右）和C端域。在T. urartu和Aegilops tauschii品种中，某些半胱氨酸残基的位置不同。系统发育分析将Avenb样b（ALPb）基因分为两组。包含18个TuALPb7A的ALPb-7A等位基因分布在第一组中，而ALPb-4A等位基因存在于另一组中。由四个等位基因（TuALPb7A-G，TuALPb7A-O，TuALPb7A-K和TuALPb7A-C）被大规模表达并纯化以评估其对面团混合性能的影响。混谱仪测试表明，这些蛋白质可以改善面团的功能特性，包括混合时间，面团的峰值耐受性和抗击性。将燕麦蛋白-样B基因在保持丰富的遗传等位基因T.乌拉尔图，并可以改善面团的功能特性。发现的新的有利等位基因将提供育种材料和小麦品质改良的理论基础。