关键词: 节节麦, 小麦, 高分子量麦谷蛋白基因, 氨基酸序列

Abstract: A novel y-type high molecular glutenin gene, Dy13^t, was cloned and sequenced from Aegilops tauschii. The deduced amino acid sequence of Dy13^t was compared with those of homologous of common wheat and Aegilops tauschii. The result indicates that the whole protein amino acid sequence of Dy13^t, is different from those of genes encoded either by common wheat A, B and D genome or by Aegilops tauschii D genome which we have known. The comparison results also show that the amino acid residues of signal peptide, N-terminal and C-terminal of six genes are the same except for a few amino acid residues substitution. The divergence of 6 genes is made by the difference of repetitive domain, especially by the variation of repeated hexpeptide(PGQGQQ) and nonapeptide(GYYPTSP/SQQ or GY/HYPT/ASLQQ). Up till now, the repetitive domain of Dy13^t is the shortest in the D genome encoded genes. When the repetitive domain of Dy13^t is compared with Dy10, Dy12 and Dy12^t, 4 nonapeptide, 4 nonapeptide, 2 hexpeptide, and 4 nonapeptide lack Dy13^t respectively. According to the N-C aligned sequences cluster results, the 6 genes can be divided into 3 branches, each of the A, B and D genome encoded genes is included in the same branch. The 4 D genome encoded genes are clustered in the same branch, each of the 2 genes from common wheat D genome and Aegilops tauschii D genome are clustered in the same sub-branch.

Key words: Aegilops tauschii, Triticum aestivum, HIGH-MOLECULAR-WEIGHT GLUTENIN GENE, AMINO ACID SEQUENCE