关键词: 小麦, α/β-醇溶蛋白基因, 序列分析

Abstract: Using PCR amplification method, the full coding regions (open reading frame, ORF) of three α/β-gliadin genes Gli-AS1643-1 (GenBank No.DQ166376), Gli-AS1643-2 (GenBank No.DQ166377) and Gli-AS1643-3 (GenBank No.DQ166378), were isolated form the genomic DNA of Sichuan wheat landrace AS1643. Among which, Gli-AS1643-1 and Gli-AS1643-2 were 873 bp and 852 bp, and could encode two mature proteins with 270 and 263 amino acid residues, respectively. Due to one stop codon in its coding region, Gli-AS1643-3 was a pseudogene. Multiple sequence alignment analysis suggested that Gli-AS1643-1, Gli-AS1643-2 and Gli-AS1643-3 have the higher similarity in their structure with the known α/β-gliadin genes in GenBank. N-terminal amino acid sequences of the three cloned genes were basically consistent with other α-, β-, γ- and α/β-gliadins, whereas it was clearly different with ω-gliadins and LMW-GS. N-terminal amino acid sequence was dodecapeptide tandem repeat with five more closely proline boxes and two polyglutamine domains encoded by microsatellite-like sequences. Sequence active in celiac disease and adenovirus type twelve infection sequences were presented in N-domain and in C-domain of Gli-AS1643-2, respectively. The six conserved cysteine residues would form three intramolecular disulfide bonds in Gli-AS1643-1, Gli-AS1643-2 and Gli-AS1643-3, respectively.

Key words: Wheat, α/β-gliadin gene, Sequence analysis