Cloning and Characterization of Low-Molecular-Weight Glutenin Subunit Alleles from Chinese Wheat Landraces (Triticum aestivumL.)

摘要

Low-molecular-weight glutenin subunits (LMW-GS) are of great importance in processing quality and participate in the formation of polymers in wheat. In this study, eight new LMW-GS alleles were isolated from Chinese wheat landraces (Triticum aestivumL.) and designated asGlu-A3-1a,Glu-A3-1b,Glu-B3-1a,Glu-B3-1b,Glu-B3-1c,Glu-D3-1a,Glu-D3-1b, andGlu-D3-1c, which were located at theGlu-A3,Glu-B3, andGlu-D3loci, respectively. Based on the proteins encoded, the number of deduced amino acids ofGlu-B3alleles was approximately 50 more than those ofGlu-A3andGlu-D3alleles. The first cysteine ofGlu-A3andGlu-D3alleles was located at the N-terminal domain, while that ofGlu-B3alleles was found in the repetitive domain, which may lead to the different functioning in forming disulfide bonds. All the eight genes were LMW-m types and the new allele ofGlu-B3-1awhich had nine cysteine residues may be the desirable LMW-GS gene for improving bread-making quality.