【摘要】 根据α-醇溶蛋白基因编码区两端保守区设计引物,对小麦(Triticum aestivum)品种良麦2号总DNA进行PCR扩增得到约900bp的DNA片段,经克隆测序,获得3条基因序列,GenBank登录号分别为:DQ417343、DQ417344和DQ417345。其中,DQ417343和DQ417345分别为942和921bp,可分别编码313和306个氨基酸残基;而DQ417344编码区长度为852bp,由于存在2个提前终止密码子,不能编码有功能的成熟蛋白,为假基因。序列比对显示这3个基因与已知α-醇溶蛋白基因有较高一致性,但在N-端重复区和多聚谷氨酰胺区存在较大差异:重复区的差异主要是重复单元PFPQPQL出现频率不同;而多聚谷氨酰胺区的主要差异是长度不同,一些谷氨酰胺突变为其它氨基酸。更多还原

【Abstract】 According to the two distal and conserved regions of known α-gliadin genes, gene-specific primers for α-gliadin were designed to amplify the full gene coding regions. The amplified fragments were cloned and sequenced. Three clones with the GenBank accession No. DQ417343, DQ417344 and DQ417345 were screened out, among which, the coding regions of DQ417343 and DQ417345 were 942 and 921 bp, encoding the proteins with 313 and 306 amino acid residues, respectively; DQ417344 was a pseudogene by the definition of two in-frame stop codons. Multi-alignment analysis indicated that these sequences had higher similarity with other α-gliadin genes, and the differences mainly existed in the N-terminal repetitive domain and the two polyglutamine regions. It was noteworthy that variable number of repeat unit(PFPQPQL) was involved. For the two polyglutamine regions, length of sequence was strongly different and some glutamines were replaced by other residues.更多还原