中文摘要：

为了获得优良品种陕253有关ω-醇溶蛋白基因的相关信息,根据已报道的ω-醇溶蛋白基因序列设计特异引物,采用PCR方法对小麦（Triticum aestivumL.）品种陕253总DNA进行扩增,回收1000bp左右的片段,经纯化、克隆并测序,获得5个不同的ω-醇溶蛋白新基因,命名为Gli-S253-1、Gli-S253-2、Gli-S253-3、Gli-S253-4和Gli-S253-5,GenBank登录号分别为：GQ423428、GQ423429、GQ423430、GQ423431和GQ423432。序列分析表明：（1）ω-醇溶蛋白基因沉默主要有4种类型（Q→＊、I→＊、R→＊和W→＊）,并以第一种类型为主（占66.6%）;（2）从三联体密码角度看,谷氨酰胺（Q）的两种编码方式最容易发生沉默突变（CAA→TAA和CAG→TAG）;（3）从突变位点来看,沉默主要发生于三联体密码的第一位碱基（占77.8%）,第二位碱基发生突变的频率占33.3%,但未见第三位沉默突变;GQ423428出现了罕见的ATA→TAA类沉默,同时涉及两个位点的变异;（4）就基因沉默突变的数目而言,GQ423428和GQ423429各高达6次,其中4个位点（349、373、478和592）为上述5条记录所共有;（5）从编码成熟蛋白的结构上看,沉默突变主要集中于ω-醇溶蛋白重复区,信号肽区及N-端区未发现此类变异;（6）进化分析表明,小麦族的ω-gliadin/secalin分成3支,其中小麦来源的ω-gliadin聚成一支。上述结果表明,本研究从陕253成功分离到5条存在丰富多样性的ω-醇溶蛋白编码基因,为深入研究优质的来源及分子辅助育种提供参考。

英文摘要：

To characterize the ω-gliadin gene family of Shaan 253,six pieces of complete coding regions were amplified from this wheat（Tricicum aestivum） variety using primer pairs designed according to the known ω-gliadin gene sequences.The amplified DNA fragments were separated and recovered from agarose gel,subsequently ligated into pMD19-T vector,and then transformed into Escherichia coli strain DH5α.Five positive clones were sequenced.And five ω-gliadin gene sequences were obtained,designated as Gli-S253-1,Gli-S253-2,Gli-S253-3,Gli-S253-4 and Gli-S253-5,respectively and the corresponding GenBank accession numbers were GQ423428,GQ423429,GQ423430,GQ423431and GQ423432,respectively.Sequence analysis showed that：（1） There were four main types of ω-gliadin gene silence（Q→＊,I→＊,R→＊ and W→＊）,of which the first type was dominant（about 66.6%）;（2） Two kinds of coding glutamine（Q） were the most likely to nonsense mutations（CAA→TAA and CAG→TAG）;（3） Gene silence occurred mainly in the triplet code of the first base（accounting for 77.8%）,mutation frequency of the second base was about 33.3%,while the third one has not been reported;there was a rare silence mutation（ATA→TAA） in GQ423428,while two loci involved in variation in a triplet code at a time;（4） The number of gene silence mutation was up to six in GQ423428 and GQ423429,including foursites（349,373,478 and 592） which occurred in all of the five genes.（5） From the structure of mature protein,nonsense mutations appeared mainly in the repeat region,rather than the signal peptide or the N-terminus of ω-gliadin;（6） Phylogenetic analysis indicated that ω-gliadin/secalin of tribe Triticeae was divided into three branches.The results from this study indicated that five pieces of ω-gliadin genes were successfully separated from Shaan 253,which could expand the genetic variation for wheat quality improvement,and even provide molecular assists during the conventional wheat breeding.