The γ-gliadin-like γ-prolamin genes in the tribe Triticeae.
The γ-prolamins are important components of seed storage proteins in wheat and other Triticeae species. Here, the γ-prolamin genes from the diploid Triticeae species were systemically characterized. Most of the γ-prolamins (except 75 K γ-secalins) characterized were defined as γ-gliadin-like γ-prolamins, since they shared same characteristic model structure with γ-gliadins. Over one-third of these putatively functional γ-prolamin peptides contained different number of cysteine residues as compared to the eight residues present in γ-gliadins. Sequence polymorphism and linkage disequilibrium analyses showed the conservation of γ-prolamin genes in Triticeae species under evolutionary selection. Phylogenetic analyses indicated that these γ-prolamin genes can not be clearly separated according to their genomic origins, reflecting the conservation of γ-gliadinlike γ-prolamin genes after the divergence of Triticeae species. A screening of coeliac disease (CD) toxic epitopes shows that the γ-prolamins from some other genomes contain much fewer epitopes than those from the A, S (B) and D genomes of wheat. These findings contribute to better understanding of γ-prolamin family in Triticeae and build a ground for breeding less CD-toxic wheat cultivars.
Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, Chengdu, Sichuan 611130, People's Republic of China. pengfeiqi@hotmail.com.
Peng-Fei
PF
Qi
Cheng-Xing
CX
Le
Zhao
Z
Wang
Yu-Bin
YB
Liu
Qing
Q
Chen
Zhen-Zhe
ZZ
Wei
Bin-Jie
BJ
Xu
Zheng-Yuan
ZY
Wei
Shou-Fen
SF
Dai
Yu-Ming
YM
Wei
You-Liang
YL
Zheng
D000595:Amino Acid Sequence; D003545:Cysteine / Q000737:chemistry; D002523:Edible Grain / Q000145:classification / Q000235:genetics*; D000939:Epitopes / Q000737:chemistry; D014644:Genetic Variation; D005903:Gliadin / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D055315:Prolamins / Q000737:chemistry / Q000235:genetics*; D054730:Protein Interaction Domains and Motifs; D016415:Sequence Alignment
D000939:Epitopes; D055315:Prolamins; D005903:Gliadin; D003545:Cysteine