四川农业大学学报 ›› 2008, Vol. 26 ›› Issue (04): 385-392.doi: 10.16036/j.issn.1000-2650.2008.04.003

• 研究论文 • 上一篇    下一篇

野生二粒小麦低分子量谷蛋白基因序列分析

伍碧华1,2, 路洁霏1,2, 胡喜贵1,2, 李平1,2, 颜泽洪1,2, 刘登才1,2, 郑有良1,2   

  1. 1. 四川农业大学 小麦研究所, 四川 温江 611130;
    2. 四川农业大学 教育部作物基因资源与遗传改良重点实验室, 四川 雅安 625014
  • 收稿日期:2008-12-18 出版日期:2008-12-31 发布日期:2017-03-03
  • 基金资助:
    国家自然科学基金(30571139);四川省教育厅重点项目;四川省学术和技术带头人培养基金

Isolation and Characterization of Two Low Molecular Weight Glutenin Subunit Genes from Triticum dicoccoides

WU Bi-hua1,2, LU Jie-fei1,2, HU Xi-gui1,2, LI Ping1,2, YAN Ze-hong1,2, LIU Deng-cai1,2, ZHENG You-liang1,2   

  1. 1. Triticeae Research Institute, Sichuan Agricultural University, Wenjiang 611130, Sichuan, China;
    2. Key Laboratory of Crop Genetic Resources and Improvement, Ministry of Education, Sichuan Agricultural University, Yaan 625014, Sichuan, China
  • Received:2008-12-18 Online:2008-12-31 Published:2017-03-03

摘要: 根据低分子量谷蛋白亚基(LMW-GS)基因编码区保守序列设计引物,用PCR方法从蛋白质含量低至13.17%的D81和高达27.20%的D42 2份野生二粒小麦(Triticum dicoccoides)中克隆得到2个LMW-GS基因序列LMW-D81和LMW-D42(GenBank上的序列号分别为FJ461691和FJ461690)。它们具有小麦低分子量谷蛋白基因的典型结构特征,其长度分别为1053bp和1011bp,并分别编码350和336个氨基酸残基的成熟蛋白。LMW-D42和LMW-D81的氨基酸序列估算分子量分别为38kDa和39kDa,说明二者均为C型亚基编码基因。LMW-D42和LMW-D81的N-末端序列都为METSHIP-,表明这2个C型亚基编码基因归属LMW-m型。同源性比对和聚类分析揭示,LMW-D81和LMW-D42均属于Glu-B3位点编码基因。LMW-D42和LMW-D81的核苷酸序列和推导的氨基酸序列一致性分别为93.94%和92.57%。与LMW-D81相比,LMW-D42除发生了22处间断性的碱基替换外,还存在一段42个碱基的缺失。对推导氨基酸序列进行的二级结构预测显示,LMW-D81和LMW-D42的蛋白质二级结构高度一致。其α-螺旋主要位于信号肽和C-末端,少量的α-螺旋和不规则卷曲构成了N-末端。大多数不规则卷曲位于重复区,仅有的一段β-折叠则出现在C-末端。同时,它们的编码区均具有分布一致的8个半胱氨酸残基,且第一和第七个半胱氨酸残基均位于无规则卷曲中。这些结构特点对小麦加工品质改良具有一定意义。

关键词: 野生二粒小麦, 低分子量谷蛋白, 基因克隆, 序列分析, 二级结构

Abstract: In this paper,PCR for the genomic DNA from Triticum dicoccoides was conducted by using a pair of primers designed according to the conservative domain from the known low molecular weight glutenin subunit genes.The two LMW-GS genes,LMW-D81 and LMW-D42 (GenBank accession number FJ461691 and FJ461690),were obtained from the accession D81 with the low protein content at 13.17% and D42 with the high protein content at 27.20%,respectively.LMW-D42 and LMW-D81 possessed the nucleotide sequences with 1011 bp and 1053 bp,and the deduced amino acid sequences with 336 and 350 amino acid residues,respectively.LMW-D42 and LMW-D81 belonged to C type genes owing to their molecular weight about 38 kDa and 39 kDa,respectively,as well as to LMW-m type genes based on the predicted protein sequences of N-terminal domain with METSHIP-.Meanwhile,LMW-D42 and LMW-D81 being allelic Glu-B3 genes were implied by homologous and cluster analyses.The similarities between their sequences were 93.94% in nucleotide and 92.57% in deduced amino acid,respectively.A single deletion for 42 bp occurred in LMW-D42 besides the substitutes at 22 interval sites,compared with LMW-D81.The predicted secondary structures of the amino acid sequences deduced from the two genes were similar.The signal peptide and C-terminal region consisted of many α-helixs.The N-terminal region was formed by a short section of both α-helixs and coils.The repetitive region was mainly occupied by coil.A single β-sheet structure was observed only in C-terminal region.Their amino acid sequences had 8 cysteine residues with similar distribution,and the first and seventh cysteine residues located in the coils.So,these structural characters of LMW-D42 and LMW-D81 might be of importance to quality improvement of bread wheat.

Key words: Triticum dicoccoides, low molecular weight glutenin, gene cloning, sequence analysis, secondary structure

中图分类号: 

  • S512.1