Identification of α-gliadin genes in Dasypyrum in relation to evolution and breeding
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To better understand molecular evolution of the large α-gliadin gene family and provide a potential value for wheat quality improvement, total 32 α-gliadin gene sequences were isolated from the two Dasypyrum species, D. villosum. (L.) Candargy and D. breviaristatum (Lindb. F.) Frederisksen. Twelve of 32 sequences contained the in-frame stop condons were predicted to be pseudogenes, suggesting the high variation of gliadin genes in Dasypyrum genome. There are five D. breviaristatum α-gliadin sequences present additional cysteine residues. Four peptides which have been identified as T cell stimulatory epitopes in celiac disease (CD) patients through binding to HLA-DQ2/8 were searched to all Dasypyrum α-gliadin gene sequences, and we found that the distribution of the epitopes varied between Dasypyrum genomes. Phylogenetic analysis of the Dasypyrum α-gliadin genes indicated that the sequences from D. breviaristatum displayed higher variation than those from D. villosum, and the genomic differentiation occurred between the two Dasypyrum species. Moreover, the promoter region of the Dasypyrum α-gliadin genes consisted of four different lengths, indicative of the retrotransposons involving the evolution of the gliadin gene promoters. Based on the specific sequences of the Dasypyrum α-gliadin promoter region, we produced sequence-characterized amplified region (SCAR) markers, and localized the Dasypyrum α-gliadin genes on chromosome 6 VS. The SCAR markers can be used to target the introgression of Dasypyrum α-gliadin genes in wheat–Dasypyrum derivatives.
KeywordsDasypyrum Gliadin Phylogenetic analysis PCR marker
We are thankful to the National Natural Science Foundation of China (No. 30671288, 30730065), Program for New Century Excellent Talents in University (NCET-06-0810) and Young Scholars Foundation from the Science and Technology Committee of Sichuan, China (2008-31-371) for their financial support. We are grateful to Prof H R Jiang for providing the seeds and we particular thank Prof. B. Friebe (Kansas State University, USA) and two anonymous reviewers for their helpful comments on the manuscript.
- Anderson OD, Litts JC, Greene FC (1997) The α-gliadin gene family. I Characterization of ten new wheat α-gliadin genomic clones, evidence for limited sequence conservation of flanking DNA, and southern analysis of the gene family. Theor Appl Genet 95:50–58. doi: 10.1007/s001220050531 CrossRefGoogle Scholar
- Chen PD, Zhang SZ, Wang XE, Wang SL, Zhou B, Feng YG et al (2002) New wheat variety Nannong 9918 with high yield and powdery mildew resistance. J Nanjing Agric Univ 25:105–106Google Scholar
- Galasso I, Blanco A, Katsiotis A, Pignone D, Heslop-Harrison JS (1997) Genome organization and phylogenetic relationships in the genus Dasypyrum analyzed by Southern and in situ hybridization of total genomic and cloned DNA probes. Chromosoma 106:53–61. doi: 10.1007/s004120050224 PubMedCrossRefGoogle Scholar
- Jiang HR, Dai DQ, Sun DF, Xiao SH (1992) New artificial genetic resources of wheat-several polyploids of Triticum–Dasypyrum. Scientia Agric Sin 25(1):89Google Scholar
- Metakavosky EV, Novoselskaya AY (1991) Gliadin allele identification in common wheat I. Methodological aspects of the analysis of gliadin patterns by one-dimensional polyacrylamide gel electrophoresis. J Genet Breed 45:317–324Google Scholar
- Pignone P, Galasso I, Blanco A, Cremonini R (2000) Heterochromatin organization in metaphase chromosomes and interphase nuclei of Dasypyrum breviaristatum (Lindb) Frederiksen. Acta Soc Bot Polon 69:5–9Google Scholar