阿拉拉特小麦高分子量谷蛋白新基因1Gy的克隆及序列分析  

Cloning and Sequence Analysis of a Novel HMW-GS Gene 1Gy from Triticum araraticum Jakubz

作　　者：徐黎黎[1] 钟美玉[1] 李伟[1] 魏育明[1] 

机构地区：[1]四川农业大学小麦研究所,四川温江611130

出　　处：《四川农业大学学报》2011年第2期141-146,共6页Journal of Sichuan Agricultural University

基　　金：四川省青年科技基金项目(2010JQ0046)

摘　　要：利用y-型高分子量谷蛋白亚基的特异引物,对阿拉拉特小麦(PI427305)的基因组DNA进行PCR扩增,得到大小为2.2 kb的目的条带,将该条带回收纯化并克隆到pMD18-T载体中,经梯度亚克隆测序拼接,得到编码区的全序列为2 202 bp(GenBank登录号:HM131806),共编码732个氨基酸。它与1Gy7*序列的同源性高达99%,而且氨基酸序列结构与大多数y-型亚基相同,推断该基因为1Gy。1Gy的分子量比1Gy7*稍小,迁移率比1Gy7*慢。与小麦属其他基因组编码的y-型亚基相比,其在靠近C端的重复区多了一个半胱氨酸残基。利用在线PSIPRED对其二级结构预测结果显示,其重复区主要是无规则卷曲结构。这些结构都可能使得1Gy对小麦加工品质产生正面影响。In this study,genomic PCR reaction of Triticum araraticum（PI427305） was carried out by using degenerate primers specific for y-type HMW-GS.A 2.2 kb DNA fragment was amplified and cloned into the pMD18-T vector.DNA sequencing was carried out by using overlapping sub-clones.The complete coding region of the gene was 2 202 bp（GenBank accession number was HM131806）,and 732 amino acid residues were encoded.It was found that the DNA sequence of this gene showed the highest identity with that of 1Gy7＊ of Triticum timopheevii Zhuk,and the corresponding amino acid sequence had the typical structure of y-type HMW-GS.So it was concluded that this gene was 1Gy.The molecular weight of 1Gy was a little smaller than that of 1Gy7＊,and the mobility of 1Gy was slower than that of 1Gy7＊.Therefore,1Gy was a novel y-type HMW-GS gene.Compared with other y-type subunits encoded by A,B and D genomes of common wheat,an extra cysteine existed in the repetitive domain near C-terminal domain of 1Gy.The repetitive domain was mainly proved to be coil by using PSIPRED.Both of them were beneficial to bread improvement.

关 键 词：阿拉拉特小麦 1Gy 分子克隆 原核表达 序列分析 

分 类 号：S512.1[农业科学—作物学]