title: Molecular Characterization and Variation of the Celiac Disease Epitope Domains among α-Gliadin Genes in Aegilops tauschii.
abstract: To explore the distribution and quantity of toxic epitopes in α-gliadins from Aegilops tauschii, a total of 133 complete α-gliadin coding sequences were obtained, including 69 pseudogenes with at least one premature stop codon and 64 genes with complete open reading frames (ORFs). Plenty of deletions and single amino acid substitutions were found in the 4 celiac disease (CD) toxic epitope domains through multiple alignments, in which the sequence of DQ2.5-glia-α2 demonstrated the most significant changes. Interestingly, 7 of the 59 α-gliadins were free of any kind of intact CD toxic epitopes, providing potential gene resources for low CD toxicity breeding of common wheat. Analysis of the neighbor-joining tree demonstrates that 2 of the totally 7 α-gliadins cluster within the homologues of Triticum (A genome), and the other 5 group with those of Aegilops Sitopsis (B genome). This result implies that the 7 α-gliadin genes may be originated from the ancestor species of Ae. tauschii, evolved by the homoploid hybrid of Triticum and Aegilops Sitopsis. The remaining 52 α-gliadins form a separate clade from other homologues of A and B genomes, suggesting a recent rapid gene expansion by gene duplication associated with the species adaptation.
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.|Institute of Plant Stress Biology, Henan University , Kaifeng, 475004, People's Republic of China.
authors.forename: Yu-Ge
authors.initials: YG
authors.lastname: Li
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.|Institute of Plant Stress Biology, Henan University , Kaifeng, 475004, People's Republic of China.
authors.forename: Hui-Hui
authors.initials: HH
authors.lastname: Liang
authors.affiliation: Institute of Plant Stress Biology, Henan University , Kaifeng, 475004, People's Republic of China.
authors.forename: Sheng-Long
authors.initials: SL
authors.lastname: Bai
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.|Institute of Plant Stress Biology, Henan University , Kaifeng, 475004, People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.|Institute of Plant Stress Biology, Henan University , Kaifeng, 475004, People's Republic of China.
authors.forename: Guiling
authors.initials: G
authors.lastname: Sun
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.
authors.forename: Ya-Rui
authors.initials: YR
authors.lastname: Su
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.
authors.forename: An-Li
authors.initials: AL
authors.lastname: Gao
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.|Institute of Plant Stress Biology, Henan University , Kaifeng, 475004, People's Republic of China.
authors.forename: Da-Le
authors.initials: DL
authors.lastname: Zhang
authors.affiliation: School of Life Science, Henan University , Kaifeng, 475004, Henan, People's Republic of China.|Institute of Plant Stress Biology, Henan University , Kaifeng, 475004, People's Republic of China.
authors.forename: Suo-Ping
authors.identifier: http://orcid.org/0000-0003-1740-7205
authors.initials: SP
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D002446:Celiac Disease / Q000276:immunology; D000939:Epitopes / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D014644:Genetic Variation; D018745:Genome, Plant; D005903:Gliadin / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D006109:Poaceae / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000276:immunology; D000072417:Protein Domains; D016415:Sequence Alignment; D014908:Triticum / Q000737:chemistry / Q000235:genetics / Q000276:immunology*
chemical_list: D000939:Epitopes; D005903:Gliadin
keywords: Aegilops tauschii; celiac disease; phylogenetic relationships; toxic epitope; α-gliadin