Molecular cloning and characterization of four i-type LMW glutenin subunit genes from T.zhukovskyi and T.compactum
Four novel low-molecular-weight glutenin subunit (LMW-GS) genes, designated TzLMW-i1, TzLMW-i2,TcLMW-i1 and TcLMW-i2, were cloned and characterized from the genomic DNA of Triticum zhukovskyi and Triticum compactum.The coding regions of TzLMW-i 1, TzLMW-i2, TcLMW-i 1 and TcLMW-i2 were759 bp, 837 bp, 756 bp and 1,170 bp in length, encoding peptides with 251, 277, 250 and 388 amino acid residues, respectively.Analysis of deduced amino acid sequences showed that the four novel genes were LMW-i types and the comparative results indicated that the four genes had similar structures and higher homologies with LMW-i-type genes than with LMW-m and LMW-s type genes.Sequence alignment results showed that TzLMW-i1, TcLMW-i1 and TcLMW-i2 have all eight cysteines at conserved positions in the C-terminal domain, whereas TzLMW-i2 has an additional cysteine residue.This additional cysteine residue was predicted to be involved in the formation of intermolecular disulfide bonds.Therefore, TzLMW-i2 may act as a chain brancher and have the possibility of increasing protein cross-links in the gluten network, forming larger glutenin polymers, which contribute to dough elasticity and high bread-making quality.Moreover, TcLMW-i2 possessed a longer repetitive domain, which was considered to be associated with good wheat quality.To investigate the evolutionary relationship of the novel genes with other storage protein genes, a phylogenetic tree was constructed.It showed that prolamin genes could be absolutely clustered into five groups, including high-molecular-weight glutenin subunits (HMW-GS), LMW-GS, α/β-, y-and ω-gliadins, and the four LMW-GS genes cloned in the present study were grouped into the LMW-i subgroup.
Q.Wang Y.Li X.Y.Li X.Xiao F.S.Sun Y.S.Wang G.Y.He G.X.Yang
The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, Chinese National Center of Plant Gene Research (Wuhan) HUST Part, College of Life Science and Technology, Huazhong University of Science (&) Technology (HUST), Wuhan, 430074, China
国际会议
The 11th International Gluten Workshop(第十一届国际谷蛋白学术研讨会)
北京
英文
148-152
2012-08-12（万方平台首次上网日期，不代表论文的发表时间）