title: Allelic variations of α-gliadin genes from species of Aegilops section Sitopsis and insights into evolution of α-gliadin multigene family among Triticum and Aegilops.
abstract: The α-gliadins account for 15-30 % of the total storage protein in wheat endosperm and play important roles in the dough extensibility and nutritional quality. On the other side, they act as a main source of toxic peptides triggering celiac disease. In this study, 37 α-gliadins were isolated from three species of Aegilops section Sitopsis. Sequence similarity and phylogenetic analyses revealed novel allelic variation at Gli-2 loci of species of Sitopsis and regular organization of motifs in their repetitive domain. Based on the comprehensive analyses of a large number of known sequences of bread wheat and its diploid genome progenitors, the distributions of four T cell epitopes and length variations of two polyglutamine domains are analyzed. Additionally, according to the organization of repeat motifs, we classified the α-gliadins of Triticum and Aegilops into eight types. Their most recent common ancestor and putative divergence patterns were further considered. This study provides new insights into the allelic variations of α-gliadins in Aegilops section Sitopsis, as well as evolution of α-gliadin multigene family among Triticum and Aegilops species.
authors.affiliation: College of Landscape and Architecture, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, China.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, Sichuan, China. hailong@cib.ac.cn.
authors.forename: Hai
authors.initials: H
authors.lastname: Long
authors.affiliation: Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, China.
authors.forename: Yu-Ming
authors.initials: YM
authors.lastname: Wei
authors.affiliation: Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, China.
authors.forename: Ze-Hong
authors.initials: ZH
authors.lastname: Yan
authors.affiliation: Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, China. youliangzheng@hotmail.com.
authors.forename: You-Liang
authors.initials: YL
authors.lastname: Zheng
mesh_terms: D000483:Alleles; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D017343:Genes, Plant; D005903:Gliadin / Q000235:genetics*; D005810:Multigene Family; D010802:Phylogeny; D006109:Poaceae / Q000235:genetics*; D017422:Sequence Analysis, DNA; D014908:Triticum / Q000235:genetics*
chemical_list: D018744:DNA, Plant; D005903:Gliadin
keywords: Celiac disease; Endosperm storage protein; Gene family; Processing quality; Wheat