Molecular characterization and phylogenetic analysis of a novel glutenin gene (Dy10.1t) from Aegilops tauschii.
A novel y-type high molecular mass glutenin subunit (HMM-GS) possessing a mobility that is slightly slower than that of the subunit Dy10 obtained by SDS-PAGE, named Dy10.1t, in the wild wheat Aegilops tauschii was identified by 1- and 2-dimensional gel electrophoresis, capillary electrophoresis, and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). The gene encoding the HMM subunit Dy10.1t was amplified with allele-specific PCR primers, and the amplified products were cloned and sequenced. The coding domain of the Dy10.1t subunit gene consisted of 1980 bp encoding a protein of 658 residues with an M rs of 68 611 Da, which was similar to the M rs determined by MALDI-TOF-MS. The deduced amino acid sequence indicated that Dy10.1t subunit displayed a greater similarity to the Dy12 subunit, differing by only 8 amino acid substitutions. Six coding region single-nucleotide polymorphisms were discovered in the Dy10.1t gene by multiple alignments (1 per 330 bp), 1 in the N-terminal domain and the others in the central repeats. Five of them resulted in residue substitutions, whereas 3 created enzyme site changes. The homology and neighbour-joining trees constructed from code domain sequences of 20 x- and y-type glutenin genes from different Triticum species separated into 2 halves, which corresponded to the x-type and y-type HMM glutenin alleles. Phylogenetic analysis revealed that the Glu-1 gene duplication event probably occurred at about 16.83 million years ago, whereas the divergence times of A, B, and D genomes within x-type and y-type halves were before 7.047 and 10.54 million years ago, respectively.
Zhang
Yanzhen
Y
Key Laboratoty of Genetics and Biotechnology, College of Life Science, Capital Normal University, Beijing, China.
Li
Qiaoyun
Q
Yan
Yueming
Y
Zheng
Jigang
J
An
Xueli
X
Xiao
Yinghua
Y
Wang
Aili
A
Pei
Yuhe
Y
Wang
Haibo
H
Hsam
Sai L K
SL
Zeller
Friedrich J
FJ
D000483:Alleles; D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D018744:DNA, Plant / Q000235:genetics* / Q000302:isolation & purification; D004591:Electrophoresis, Polyacrylamide Gel; D005821:Genetic Techniques; D005983:Glutens / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D010802:Phylogeny; D021122:Protein Subunits / Q000235:genetics / Q000302:isolation & purification; D016415:Sequence Alignment; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014908:Triticum / Q000235:genetics*
D018744:DNA, Plant; D021122:Protein Subunits; D005983:Glutens; C037302:glutenin