【摘要】 为了获得苦荞中主要过敏原的cDNA和由此推导的蛋白质序列 ,分析其结构特点 ,以苦荞幼根根尖为材料 ,提取总RNA并反转录mRNA为cDNA第一链 .通过RT PCR、3′RACE、基因克隆及序列测定 ,获得一种苦荞主要过敏蛋白基因的cDNA片段 (GenBank登录号为AY0 4 4918) .该cDNA片段由 76 8bp组成 ,包括 3′端非编码区 180个bp ,开放阅读框 5 88bp .可编码一个由 195个氨基酸残基组成的功能蛋白及一个终止密码 .苦荞主要过敏原基因与甜荞 2 2kD过敏蛋白、豆球类蛋白的核苷酸序列分别有 95 %和 93%的同源性 .其推导的氨基酸序列与甜荞球蛋白、刀豆蛋白、甜橙柠檬素分别有 93%、83%和 5 7%的同源性 .该过敏蛋白 183～ 188位氨基酸残基KEEEKE在多数不同过敏原中均存在 ,推测可能为其中的抗原决定簇序列更多还原

【Abstract】 The cDNA sequence of allergenic gene expresses a kind of 22 kD protein in tartary buckwheat (TB), was obtained using RT PCR and 3′ rapid amplification of cDNA ends (3′RACE). The cDNA sequence coding for this allergenic protein, consisted of 768 nucleotides, including 588 nucleotides in the open reading frame (ORF) and 180 nucleotides in the 3′ untranslated region. The ORF encoded a functional protein of 195 amino acids. Comparing this allergy from TB with those of common buckwheat (CB), it showed that this allergy in TB shared 95% and 93% nucleotide sequence homology with allergenic protein and legumin like protein in CB, respectively. The protein sequence of TB allergenic protein shared 93% and 83% homology with those of globulin protein in CB and sword bean protein, respectively. The conserved sequence KEEEKE at position 183 188 was probably considered to be the antigen determinant sequence similar to that of other allergenic proteins found in food and pollen.更多还原