人工合成小麦RSP的LMW-GS基因克隆

 RSP是用抗穗发芽的节节麦与圆锥小麦合成的人工六倍体小麦Triticum turgidum-Aegilops tauschii），其抗穗发芽特性在维持小麦面粉加工品质方面有着潜在的重要价值。为了了解其低分子量谷蛋白这一对小麦加工品质有直接重要影响的蛋白组分情况，本研究采用PCR法从合成小麦RSP中克隆得到3个低分子量谷蛋白亚基（LMW-GSs）基因，命名为LMWRSP-1、LMWRSP-2和LMWRSP-3。基因序列GenBank登录号分别为AY676681、AY676682和AY676683。其中，LMWRSP-1和LMWRSP3的编码区长度分别为825 bp和915 bp，可分别编码274和304个氨基酸。LMWRSP-2由于在编码区内有1个提前终止密码子，推测为不编码成熟蛋白的假基因。与已知LMW-GS基因进行比较发现，LMWRSP-1与Glu-A3位点基因的相似性最高，LMWRSP-3与Glu-D3位点的基因相似性最高。

Cloning of LMW-GS Genes from Synthetic Hexaploid Wheat ‘RSP’

RSP is a synthetic hexaploid wheat (Triticum turgidum-Aegilops tauschii) between a tetraploid wheat (T. turgidum L.) and an Ae. tauschii accession with highly tolerant to sprouting, which is of importance to maintain wheat flour making quality. LMW-GSs together with HMW-GSs, control wheat flour making quality directly. To investigate the LMW-GSs from RSP, using PCR amplification of the genomic DNA, three novel LMW-GS genes (i.e. LMWRSP-1, LMWRSP-2 and LMWRSP-3) were isolated from 'RSP', among which LMWRSP-2 (GenBank accession number: AY676682) is a pseudogene due to one stop code in its coding regions. The coding regions of LMWRSP-1 (GenBank Accession number: AY676681) and LMWRSP-3 (GenBank accession number: AY676683) are 825 and 915 bp, respectively. They encode two LMW glutenin subunits with 274 and 304 amino acid residues, respectively. Multiple sequence alignment analysis indicated that LMWRSP-1 and LMWRSP-3 have the highest similarity scores to the known LMW-GS genes encoded by Glu-A3 and Glu-D3, respectively.