豫麦50低分子量麦谷蛋白亚基基因的克隆与序列分析  

Cloning and Sequence Analysis of LMW-GS Genes from Common Wheat(Triticum aestivum L.)Cultivar Yumai 50

作　　者：李黎[1] 李锁平[1] 李玉阁[1] 

机构地区：[1]河南大学生命科学学院,河南开封475004

出　　处：《麦类作物学报》2015年第9期1215-1221,共7页Journal of Triticeae Crops

基　　金："十二五"农村领域国家科技计划课题(2012AA101105);自然科学基金面上项目(31271713);河南省高等学校重点科研项目(15A180011)

摘　　要：为揭示Glu-D3住点编码的低分子量谷蛋白亚基（LMW—GS）基因的分子特征，并开发能有效地应于育种选择的分子标记，根据已注册的D基因组来源的LMW—GS基因编码区的保守区域，设计1对特异性简并引物，采用基因组PCR法，从豫麦50中克隆出LMW—GS基因后进行序列分析。结果表明，本研究共得到了6个具有独特编码区的核苷酸序列（命名为LMW-Y50-1～LMW-Y50-6；GenBank注册号为JN831414～JN831417、HM055908和JX828375）。其中，4个（LMW-Y50—2，LMW-Y50～4～LMW-Y50—6）具有完整的开放阅读框。推导的氨基酸序列比对分析表明，这4个基因均具有LMW—m型LMW-GS的典型分子特征，其中，LMW-Y50—5缺失N-末端第1个保守的半胱氨酸残基，LMW-Y50—6在C-末端I区含有1个额外的半胱氨酸残基，LMW-Y50—2和LMW-Y50—4均含有8个保守的半胱氨酸残基。根据N-末端和C-末端保守序列，4个基因均属于定位在1D染色体上的IV型7、8和10组基因。所得基因序列与36个代表不同位点、不同等位变异或不同单倍型LMw—GS基因序列的聚类分析表明，4个基因分别与D3—2、D3-4和D3—6单倍型有更高的同源性。表明本研究设计的简并引物可对D基因组来源的rnI型LMW-GS基因进行特异扩增。而考虑到半胱氨酸残基数目和位置对面筋品质的重要影响，推测含有异常半胱氨酸残基数目的LMW-Y50—3和LMW-Y50—4基因，尤其是LMW-Y50-3基因，可能与豫麦50优质弱筋的面筋品质有关。In order to explore the novel LMW-GS genes encoded by Glu-D3 locus and reveal the constitution of the LMW-GS genes, total 6 unique clones （designated as LMW-YSO-1-LMW-YSO-6, Gen- Bank No. JN831414-JN831417, HM055908 and JX828375）, including 4 （LMW-YSO-2, LMW-YSO- 3-LMW-YSO-6）novel LMW-GS genes with full-ORF were amplified and cloned from common wheat cultivar Yumai 50 using a PCR-based strategy with a pair of degenerate primers. Comparative analysis of the deduced amino acids sequences showed that 4 LMW-GS with full-ORF had the typical structural characters of LMW-m proteins reported previously except LMW-YSO-5 with a lack of the first conserved cysteine residue in the N-terminal region while LMW-YSO-6 with an additional cysteine residue in the C-terminal domain I. According to their N- and C-terminal conserved sequences, all the 4 novel genes were located on chromosome 1D because they belonged to group 7, 8 and 10 of type IV. Homological analysis of the deduced amino acid sequences among the 4 novel genes and other 36 genes representing different allelic variations or haplotypes of Glu-3 loci showed that all the 4 genes in this work had a relative highly homology with the genes of D3-2, D3-4 and D3-6 haplotypes, which further confirmed that the 4 LMW-GS genes were most likely originated from chromosome 1D. In conclusion, it was suggested that this pair of primes can amplify the LMW-m genes specific for Glu-D3 locus, and given the important role of the number and sites of eysteine residues in gluten quality, it was strongly suggested that the two protein with odd number cysteine residues, especially LMW-Y50-3, were associated with the weak gluten of common wheat cultivar Yumai 50.

关 键 词：LMW—GS 豫麦50 基因克隆 序列分析 

分 类 号：S512.1[农业科学—作物学] S330