中文摘要：

【目的】研究普通小麦品种选育过程中低分子量谷蛋白亚基（LMW-GS）的变化特性，理解该基因家族成员多样性的起源，并为小麦品质改良提供参考。【方法】以3套小麦高代杂交品系（F5／F6）为材料，利用毛细管电泳（cE）技术从储藏蛋白水平鉴定LMW-GS亚基的变化；根据GenBank中已公布的LMW-GS编码序列设计特异性引物，进行PCR扩增、克隆、测序及序列分析。【结果】毛细管电泳结果表明，与亲本相比，高代供试品系均保持了相对稳定的LMW-GS数目，但多个亚基在籽粒中的最终含量却发生明显变化；同时，测试品系还产生了亲本所不具有的新条带。对克隆获得的54条序列（GenBank登录号KC222070-KC222121和KC478714-Ke478715）进行序列分析，均具有LMW-GS的典型结构，包括相对保守的信号肽、存在丰富变异的中间重复区及保守的C-端，因此属于LMW-GS基因家族成员；子代与对应亲本的相似性分析表明，3套材料中均存在极端保守序列，子代序列与其相应父本序列完全一致，且都属于LMW-m型亚基；相对保守序列所占比例最大，由于微弱的SNPs，双亲都充当变异序列的供体；蛋白质序列分析还揭示了额外Cys亚基的产生过程。此外，还发现含10个或11个半胱氨酸（Cys）残基的LMIC-GSoCys残基的变异主要发生在C-端Ⅲ区，只有1条序列的Cys变异发生在c一端Ⅱ区。【结论】小麦品种选育过程，父源性的LMW-m型低分子量谷蛋白亚基较其它类型亚基更趋于序列的保守，SNPs则是产生LMw-GS多样性的主要动力。

英文摘要：

[Objective] To understand the diversity origin of low-molecular-weight glutenin subunits （LMW-GS）, and provide references for wheat quality improvements, the variation features of LMW-GS in the formation of wheat cultivars were characterized. [Method] With the capillary electrophoresis （CE）, the seeds of three sets of hybrid materials （F5/F6）, together with their corresponding parents, were used to test the variability of the LMW-GS. A series of specific primers, designed according to the genetic sequence published in GenBank, PCR amplification, gene cloning, and sequence analysis were employed to characterize the features of LMW-GSs. [Result] The results of CE indicated that all the tested lines contained the relatively stable numbers of LMW-GS compared to the parents, while the accumulation amount of several subunits increased significantly. On the basis of the sequence analysis, all of the 54 genes （GenBank access numbers from KC222070 to KC222121, and from KC478714 to KC478715） belonged to the lmw-gs gene family because of their typical structure of LMW-GS, including the relatively conserved signal peptides,intermediate repeating regions with abundant variations and the conserved C-terminal domain. The similarity alignment between the advanced lines and their parents revealed that all the three sets of hybrid materials shared the extremely conserved sequences with their relevant parental lines and all these common sequences belonged to LMW-m subunits. The relatively conserved sequences originated from SNPs were the major proportion and both parents have been acted as their donors. It was also found the fine procedure of the extra Cys residue in the LMW-GS during the formation of wheat cultivars. What＇s more, LMW-GS with 10 or 11 Cys residues was also observed in the present study. The variation of Cys residues mainly occurred in the C-terminal region II, while only one variation in the C-terminal region Ill. [Conclusion] During the process of wheat breeding, the m-type LMW-GS from paternal