Molecular characterization of of alpha-gliadin genes from wild emmer wheat (Triticum dicoccoides).
According to the two distal and conserved regions of known alpha-gliadin genes, gene-specific primers for alpha-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 alpha-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.
Qi
Peng-Fei
PF
Triticeae Research Institute, Sichuan Agricultural University, Yaan, Sichuan 625014, People's Republic of China.
Yue
Yuan-Wen
YW
Long
Hai
H
Wei
Yu-Ming
YM
Yan
Ze-Hong
ZH
Zheng
You-liang
YL
D000595:Amino Acid Sequence; D001483:Base Sequence; D003062:Codon / Q000235:genetics; D017931:DNA Primers; D040461:Gene Components; D005903:Gliadin / Q000235:genetics*; D008969:Molecular Sequence Data; D011544:Pseudogenes / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014908:Triticum / Q000235:genetics*
D003062:Codon; D017931:DNA Primers; D005903:Gliadin