Cloning of low-molecular-weight glutenin subunit gene from Sichuan wheat landrace AS1643 and its secondary structure prediction
四川小麦地方品种AS1643中低分子量谷蛋白基因的克隆及其蛋白质的二级结构预测

The full-length coding region (open reading frame, ORF) of low-molecular-weight glutenin subunit (LMW-GS ) gene was amplified from Sichuan wheat landrace accession AS1643 by using the primer pairs P1/P2, which were designed according to wheat LMW-GS conservative domains. The amplified DNA fragment was separated and recovered from agarose gel, subsequently cloned into pMD18-T vector, and then transformed into E. coli strain DH5a. One positive clone LMW-AS1643 (GenBank accession No. EF 190322) was selected and sequenced. It had a coding region of 909 bp, and encoded a mature protein of 302 amino acid residues. Sequence analysis suggested that LMW-AS1643 was a typical LMW-GS gene. The deduced amino acid sequence comparison suggested that LMW-AS1643 had a high similarity with other known LMW-GS genes, with the highest similarity of 93.40 %Bioinformatics analysis indicated that among the three types of secondary structures, content of coil was the highest with 67.90 %, a-helix was the second with 30.46%, and b-sheet was the lowest with 1.64%.