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本研究从长穗偃麦草与老芒麦中分离了63个a-醇溶蛋白基因的开放阅读框,并进行了序列分析,结果表明90%的基因中含有提前终止密码子或移码突变.与已经发表的a-醇溶蛋白基因序列比对发现,这些基因都编码相似的信号肽、重复区和C-末端,但在两个多聚谷氨酰氨区差异明显.依据重复区中前三个氨基酸序列分析,出现了GRV和RV两种新的亚基类型;在第一个多聚谷氨酰氨区出现了(Q)_3R(Q)_5、(Q)_2AR(Q)_5、(Q)_3A新类型.乳糜泻抗原分析显示,来自老芒麦的一个真基因EU016530中含有两种乳糜泻抗原(glia-a2和glia-a),而来自长穗偃麦草的真基因中没有发现乳糜泻抗原的存在,仅有假基因EU018257含有乳糜泻抗原glia-a.进化分析表明,二倍体长穗偃麦草a-醇溶蛋白基因与十倍体的长穗偃麦草a-醇溶蛋白基因有较近的亲缘关系;而老芒麦的a-醇溶蛋白基因与其它小麦族的基因聚在一起.“,”Sixty-three a-gliadin open reading frames (ORF) were characterized from diploid Lophopyrum elongaturn and tetroploid Elymus sibiricus.Sequence comparison revealed that about 90% of them contained an internal stop codon or frameshift.Alignment between these ORFs and reported ot-gliadin sequences reveal that they coded identical signal peptide domain,repetitive domain and C-terminal region,except polyglumatine domains.Analysis of the first three codons in repetitive domains reveals two new types of motifs (GRV and RV).Novel types of motifs,including (Q)_3AR(Q)_5,(Q)_2AR(Q)_5,(Q)_3A,were characterized in the first polyglumatine region.Three known types of celiac disease (CD) epitopes in Triticum were screened and compared in the repetitive and the C-terminal unique domains.A potential real gene (EU016530) from E.sibiricus contained two types of CD epitode (glia-a2 and glia-a),whereas,the real genes from diploid L.elongatum are found to contain no CD epitode,only with pseudogenes EU018257 containing glia-a.Phylogenetic analysis showed that a-gliadins from diploid L.elongatum were closely related to those from decaploid L.elongatum,while that from E.sibiricus were more homologous with those from other Triticum species.