Molecular characterization of two silenced y-type genes for Glu-B1 in Triticum aestivum ssp. yunnanese and ssp. tibetanum.
The high molecular weight glutenin subunits (HMW-GSs) are a major class of common wheat storage proteins. The bread-making quality of common wheat flour is influenced by the composition of HMW-GSs. In the present study, two unexpressed 1By genes from Triticum aesitvum L.ssp.yunnanese AS332 and T. aesitvum ssp.tibetanum AS908 were respectively cloned and characterized. The results indicated that both of the silenced 1By genes in AS332 and AS908 were 1By9. In contrast to previously reported mechanisms for silenced genes 1Ax and 1Ay, which was due to the insertion of transposon elements or the presence of premature stop codon via base substitution of C-->T transition in trinucleotides CAA or CAG, the silence of 1By9 genes was caused by premature stop codons via the deletion of base A in trinucleotide CAA, which lead to frameshift mutation and indirectly produced several premature stop codons (TAG) downstream of the coding sequence.
Yuan
Zhong-Wei
ZW
Triticeae Research Institute, Sichuan Agricultural University, Dujiangyan 611830, China.
Chen
Qi-Jiao
QJ
Zhang
Lian-Quan
LQ
Yan
Ze-Hong
ZH
Zheng
You-Liang
YL
Liu
Deng-Cai
DC
D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D004591:Electrophoresis, Polyacrylamide Gel; D020868:Gene Silencing; D017343:Genes, Plant; D005983:Glutens / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames / Q000235:genetics; D016133:Polymerase Chain Reaction; D021122:Protein Subunits / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014908:Triticum / Q000235:genetics*
D021122:Protein Subunits; D005983:Glutens; C037302:glutenin