普通小麦Glu-3位点基因单元型的分离和序列分析

Isolation and Sequence Analysis of LMW-GS Gene at the Glu-3 Loci in Common Wheat

为了从分子水平上探讨优质小麦资源中LMW-GS等位基因与小麦品质的关系,以及在改善小麦品质方面的潜在价值,利用小麦Glu-A3和Glu-B3基因的特异引物从强筋型、中筋型和弱筋型小麦共计10份材料中分离出LMW-GS基因后进行序列分析。结果表明,共发现14个新的核苷酸变异类型和4个肽链变异类型。其中,14个新的核苷酸变异类型中,4个为Glu-A3基因变异类型,1个为Glu-B3基因变异类型,9个为Glu-D3基因变异类型。值得注意的是,有2个半胱氨酸数目特殊的亚基类型被发现,一个是来自师栾02-1含有9个半胱氨酸残基的GluA3-18基因,另一个是来自偃展4110含有7个半胱氨酸残基的GluD3-13基因。

Low-molecular-weight glutenin subunits （LMW-GS） are major fractions of wheat gluten,and have great effects on dough extensibility and food processing quality. In this study,the specific primers of Glu-A3 and Glu-B3 genes were used to identify and amplify the allelic variations of LMW-GS genes from ten wheat varieties with different gluten content. A total of 14 new DNA haplotypes were identified,including four haplotypes at Glu-A3,one haplotype at Glu-B3 and nine haplotypes at Glu-D3. Among them,the corresponding peptide of GluA3-18 from wheat variety Shiluan 02-1 contains nine cysteine residues,and the corresponding peptide of GluD3-13 from Yanzhan 4110 has seven cysteine residues,both of which belong to the specific subunits compared with others with eight cysteine residues. The results provide the basis for further study of LMW-GS genes and quality improvement of wheat.