Abstract
According to the two distal and conserved regions of known α-gliadin genes, gene-specific primers for α-gliadin were designed, and the coding regions of four gliadin genes (i.e. GliTd-1, GliTd-2, GliTd-3 and GliTd-4) with the length of about 800 bp were isolated from the genomic DNA of wild emmer wheat (Triticum dicoccoides). No introns were observed. Sequence comparison indicated that these genes should be classified as α-gliadins. GliTd-3 (GenBank accession No.DQ140351) and GliTd-4 (DQ140352) were potentially functional, whereas GliTd-1 (DQ140349) and GliTd-2 (DQ140350) were both pseudogenes by the definition of in-frame stop codons and frameshifts. Six conserved cysteine residues were observed. Sequence analysis suggested that the motif units of repetitive domain for the four newly detected genes were different from the known genes, and the QQQP sequence before the position 60 was more toxic to coeliac patients. Codons for proline were strongly biased. Codons (CAG and CAA) for glutamine were clustered into the specific regions, and the high percentage of pseudogenes resulted from the mutation of CAG → TAG.
Abbreviations | ||
BLAST | = | basic local alignment search tool |
CD | = | celiac disease |
dNTP | = | deoxyribonucleoside triphosphate |
DNA | = | deoxyribonucleic acid |
2-D PAGE | = | 2-Dimensional polyacrylamide gel electrophoresis |
ER | = | endoplasmic reticulum |
LMW | = | low molecular weight |
ORF | = | open reading frame |
PCR | = | polymerase chain reaction |
RNA | = | ribonucleic acid |
Abbreviations | ||
BLAST | = | basic local alignment search tool |
CD | = | celiac disease |
dNTP | = | deoxyribonucleoside triphosphate |
DNA | = | deoxyribonucleic acid |
2-D PAGE | = | 2-Dimensional polyacrylamide gel electrophoresis |
ER | = | endoplasmic reticulum |
LMW | = | low molecular weight |
ORF | = | open reading frame |
PCR | = | polymerase chain reaction |
RNA | = | ribonucleic acid |
Acknowledgements
The authors thank Dr Bernard R. Baum of Agriculture and Agri-Food Canada for critical review of the manuscript. This work was supported by the National Natural Science Foundation of China (No. 30300219) and the FANEDD projects (No. 200357 and 200458) from Education Ministry of China. Y.-M. Wei was supported by the Program for New Century Excellent Talents in University of China. Y.-L. Zheng was supported by the Program for Changjiang Scholars and Innovative Research Teams in University of China (IRT0453).
Notes
† The first two authors contributed equally to this paper.