Zhang W, Gianibelli M C, Rampling L R, Gale K R
Commonwealth Scientific and Industrial Research Organisation, Plant Industry, GPO Box 1600, ACT 2601 Canberra, Australia.
Theor Appl Genet. 2004 May;108(7):1409-19. doi: 10.1007/s00122-003-1558-8. Epub 2004 Jan 16.
PCR was used to amplify low-molecular-weight (LMW) glutenin genes from the Glu-A3 loci of hexaploid wheat cultivars containing different Glu-A3 alleles. The complete coding sequence of one LMW glutenin gene was obtained for each of the seven alleles Glu-A3a to Glu-A3g. Chromosome assignment of PCR products using Chinese Spring nulli-tetrasomic lines confirmed the amplified products were from chromosome 1A. All sequences were classified as LMW-i-type genes based on the presence of an N-terminal isoleucine residue and eight cysteine residues located within the C-terminal domain of the predicted, mature amino acid sequence. All genes contained a single uninterrupted open reading frame, including the sequence from the Glu-A3e allele, for which no protein product has been identified. Comparison of LMW glutenin gene sequences obtained from different alleles showed a wide range of sequence identity between the genes, with between 1 and 37 single nucleotide polymorphisms and between one and five insertion/deletion events between genes from different alleles. Allele-specific PCR markers were designed based on the DNA polymorphisms identified between the LMW glutenin genes, and these markers were validated against a panel of cultivars containing different Glu-A3 alleles. This collection of markers represents a valuable resource for use in marker-assisted breeding to select for specific alleles of this important quality-determining locus in bread wheat.
采用聚合酶链式反应（PCR）从含有不同Glu - A3等位基因的六倍体小麦品种的Glu - A3位点扩增低分子量（LMW）麦谷蛋白基因。获得了从Glu - A3a到Glu - A3g这七个等位基因中每个等位基因的一个LMW麦谷蛋白基因的完整编码序列。使用中国春缺体 - 四体品系对PCR产物进行染色体定位，证实扩增产物来自1A染色体。根据预测的成熟氨基酸序列的C末端结构域中存在N末端异亮氨酸残基和八个半胱氨酸残基，所有序列均被归类为LMW - i型基因。所有基因都包含一个单一的不间断开放阅读框，包括来自Glu - A3e等位基因的序列，尚未鉴定出该基因的蛋白质产物。对从不同等位基因获得的LMW麦谷蛋白基因序列进行比较，结果表明这些基因之间的序列同一性范围很广，不同等位基因的基因之间存在1至37个单核苷酸多态性以及1至5个插入/缺失事件。基于LMW麦谷蛋白基因之间鉴定出的DNA多态性设计了等位基因特异性PCR标记，并针对一组含有不同Glu - A3等位基因的品种对这些标记进行了验证。这组标记是用于标记辅助育种的宝贵资源，可用于选择面包小麦中这个重要品质决定位点的特定等位基因。
