摘要
Gliadins are the major components of storage proteins in wheat and play an important role in determining the extensibility properties of dough.In the present work,six novel full-length γ-gliadin genes were cloned from the C genome of Aegilops markgrafii using a PCR-based strategy.Analysis of the deduced amino acid sequences showed that the cloned genes had primary structures that were similar,but not identical,to published γ-gliadins from other wheat-related species.The lengths of the open reading frames(ORFs)ranged from 909 to 963 bp,and the repetitive and glutamine-rich domains were mainly responsible for the size of the proteins.An extra cysteine residue was present in the repetitive domain of sequence JX566513.All amino acid sequences of γ-gliadin genes from Ae.markgrafii were searched for the five peptides identified as T cell stimulatory epitopes in celiac disease(CD)patients.Peptide Gliγ-3 was present in sequences JX566513 and JX566514.Peptide Gliγ-5 was present only in JX566513.The otherγ-gliadins contained no toxic epitopes.These results provide information to better understand the use of Ae.markgrafii in wheat breeding and the evolutionary relationship of theγ-gliadin genes in Ae.markgrafii and other Triticeae species.
Gliadins are the major components of storage proteins in wheat and play an important role in determining the extensibility properties of dough.In the present work,six novel full-length γ-gliadin genes were cloned from the C genome of Aegilops markgrafii using a PCR-based strategy.Analysis of the deduced amino acid sequences showed that the cloned genes had primary structures that were similar,but not identical,to published γ-gliadins from other wheat-related species.The lengths of the open reading frames(ORFs)ranged from 909 to 963 bp,and the repetitive and glutamine-rich domains were mainly responsible for the size of the proteins.An extra cysteine residue was present in the repetitive domain of sequence JX566513.All amino acid sequences of γ-gliadin genes from Ae.markgrafii were searched for the five peptides identified as T cell stimulatory epitopes in celiac disease(CD)patients.Peptide Gliγ-3 was present in sequences JX566513 and JX566514.Peptide Gliγ-5 was present only in JX566513.The otherγ-gliadins contained no toxic epitopes.These results provide information to better understand the use of Ae.markgrafii in wheat breeding and the evolutionary relationship of theγ-gliadin genes in Ae.markgrafii and other Triticeae species.
基金
financially supported by the National Natural Science Foundation of China (nos. 31520103911, 31071405, and 31471488)
National Basic Research Program of China (no. 2014CB138100)
National Key Research and Development Program of China (no. 2016YFD0100102)
Genetically Modified Organism Breeding Major Projects (no. 2016ZX08002003)
