滨麦低分子量谷蛋白亚基(LMW-GS)基因的分离与序列分析  

Isolation and Sequence Analysis of Low Molecular Weight Glutenin Subunit from Leymus mollis

作　　者：赵继新[1] 周博[1] 庞玉辉[1] 王玉卿[1] 武军[1] 陈新宏[1] 程雪妮[2] 刘淑会[1] 傅杰[1] 

机构地区：[1]西北农林科技大学农学院,陕西杨凌712100 [2]西北农林科技大学生命学院,陕西杨凌712100

出　　处：《植物科学学报》2011年第6期704-711,共8页Plant Science Journal

基　　金：国家自然科学基金项目(30771345);陕西省"13115"科技创新工程计划项目(2009ZDKG-11;2010ZDKG-08);西北农林科技大学唐仲英育种基金项目

摘　　要：采用PCR方法,从滨麦(Leymus mollis)基因组中分离出8条LMW-GS基因序列。核苷酸序列分析表明,序列GQ169791在起始密码子上游包含318 bp的启动子序列,该序列包含-300元件、GCN4 motif、种子贮藏蛋白盒等基因特异表达的顺式或反式作用调控元件。推导的氨基酸序列分析表明,8条序列的编码区依次有信号肽,N-末端区,中部重复区和C-末端Ⅰ、Ⅱ、Ⅲ区等典型LMW-GS多肽一级结构特征;序列HQ416909、HQ416914和HQ416915具有单一完整的开放阅读框(ORF);序列GQ169791、HQ416910、HQ416911、HQ416912和HQ416913在中部重复区和C-末端区出现了4个或5个提前终止密码子,推断其为假基因。8条序列都含有8个或9个半胱氨酸残基(C),N-末端区起始氨基酸序列为METSRIPG-或METTRIPG-,推断其为LMW-m型LMW-GS基因。系统进化分析表明,8条序列与华山新麦草(Psathyrostachys huashanica)LMW-GS基因(HM475146,GQ223386)和野大麦(Hordeum brevisubulatum)的B-hordein基因(AY695368)具有相对较近的同源关系。该研究为挖掘利用滨麦LMW-GS的基因提供了理论依据,对小麦品质改良具有一定参考价值。Eight sequences of low molecular weight glutenin subunit（LMW-GS） were isolated from the genome of Leymus mollis by AS-PCR.Nucleotide sequence analysis showed that sequence GQ169791 was composed of a promoter 318 bp,and a coding region,length of 894 bp.The promoter sequence from 5’ to 3’ flanking contained multiple cis-or trans-acting regulatory elements on glutenin gene-specific expression,such as-300 element,GCN4 motif,E-box,Prolamin box,and TATA box.Deduced amino acid sequence analysis indicated that the coding region of these eight sequences had typical multi-peptide primary structure of LMW-GS： signal peptide,N-terminal region,central repeat region,and C-terminal Ⅰ,Ⅱ,Ⅲ domains;Sequence HQ416909,HQ416914 and HQ416915 had the single complete opening reading frame（ORF）,while sequence GQ169791,HQ416910,HQ416911,HQ416912 and HQ416913 were likely pseudogenes due to the four or five early termination codons in the central repeat region and C-terminal domain.There were eight or nine cysteine residues in these eight amino acid sequences,and the starting amino acid sequence in the N-terminal region was METSRIPG-or METTRIPG-,which demonstrated that they were m-type LMW-GS genes.Phylogenetic analysis indicated that these eight sequences may have a comparatively close homologous relationship with the LMW-GS genes（HM475146,GQ223386） from Psathyrostachys huashanica and the B-hordein gene（AY695368） from Hordeum brevisubulatum.This research provides a theoretical basis for excavating and utilizing the LMW-GS gene of Leymus mollis,and offers some reference value to wheat quality improvement.

关 键 词：滨麦 低分子量谷蛋白亚基(LMW-GS) 分离 序列分析 

分 类 号：Q943.2[生物学—植物学]