Cao Dong, Wang Hongxia, Zhang Bo, Liu Baolong, Liu Dengcai, Chen Wenjie, Zhang Huaigang
Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai, 810008, China.
Key Laboratory of Crop Molecular Breeding of Qinghai Province, Xining, Qinghai, 810008, China.
Genetica. 2018 Feb;146(1):45-51. doi: 10.1007/s10709-017-9995-5. Epub 2017 Oct 13.
Avenin-like storage proteins influence the rheological properties and processing quality in common wheat, and the discovery of new alleles will benefit wheat quality improvement. In this study, 13 avenin-like b alleles (TaALPb7D-A-M) were discovered in 108 Aegilops tauschii Coss. accessions. Ten alleles were reported for the first time, while the remaining three alleles were the same as alleles in other species. A total of 15 nucleotide changes were detected in the 13 alleles, resulting in only 11 amino acid changes because of synonymous mutations. Alleles TaALPb7D-E, TaALPb7D-G, and TaALPb7D-J encoded the same protein. These polymorphic sites existed in the N-terminus, Repetitive region (Left), Repetitive region (Right) and C-terminus domains, with no polymorphisms in the signal peptide sequence nor in those encoding the 18 conserved cysteine residues. Phylogenetic analysis divided the TaALPb7Ds into four clades. The Ae. tauschii alleles were distributed in all four clades, while the alleles derived from common wheat, TaALPb7D-G and TaALPb7D-C, belonged to clade III and IV, respectively. Alleles TaALPb7D-G and TaALPb7D-C were the most widely distributed, being present in nine and six countries, respectively. Iran and Turkey exhibited the highest genetic diversity with respect to TaALPb7D alleles, accessions from these countries carrying seven and six alleles, respectively, which implied that these countries were the centers of origin of the avenin-like b gene. The new alleles discovered and the phylogenetic analysis of avenin-like b genes will provide breeding materials and a theoretical basis for wheat quality improvement.
类燕麦贮藏蛋白影响普通小麦的流变学特性和加工品质，新等位基因的发现将有助于小麦品质的改良。本研究在108份节节麦材料中发现了13个类燕麦b等位基因（TaALPb7D-A-M）。其中10个等位基因是首次报道，其余3个等位基因与其他物种中的等位基因相同。在这13个等位基因中总共检测到15个核苷酸变化，由于同义突变，仅导致11个氨基酸变化。等位基因TaALPb7D-E、TaALPb7D-G和TaALPb7D-J编码相同的蛋白质。这些多态性位点存在于N端、重复区域（左）、重复区域（右）和C端结构域，信号肽序列以及编码18个保守半胱氨酸残基的序列中没有多态性。系统发育分析将TaALPb7D分为四个分支。节节麦的等位基因分布在所有四个分支中，而源自普通小麦的等位基因TaALPb7D-G和TaALPb7D-C分别属于分支III和IV。等位基因TaALPb7D-G和TaALPb7D-C分布最广，分别存在于9个和6个国家。伊朗和土耳其在TaALPb7D等位基因方面表现出最高的遗传多样性，来自这些国家的材料分别携带7个和6个等位基因，这意味着这些国家是类燕麦b基因的起源中心。新发现的等位基因以及类燕麦b基因的系统发育分析将为小麦品质改良提供育种材料和理论依据。
