title: Cloning, expression, and evolutionary analysis of α-gliadin genes from Triticum and Aegilops genomes.
abstract: Fifteen novel α-gliadin genes were cloned and sequenced from Triticum and related Aegilops genomes by allele-specific polymerase chain reaction (AS-PCR). Sequence comparison displayed high diversities in the α-gliadin gene family. Four toxic epitopes and glutamine residues in the two polyglutamine domains facilitated these α-gliadins to be assigned to specific chromosomes. Five representative α-gliadin genes were successfully expressed in Escherichia coli, and their amount reached a maximum after 4 h induced by isopropyl-β-D-thiogalactoside (IPTG), indicating a high level of expression under the control of T7 promoter. The transcriptional expression of α-gliadin genes during grain development detected by quantitative real-time polymerase chain reaction (qRT-PCR) showed a similar up-down regulation pattern in different genotypes. A neighbor-joining tree constructed with both full-open reading frame (ORF) α-gliadin genes and pseudogenes further revealed the origin and phylogenetic relationships among Triticum and related Aegilops genomes. The evolutionary analysis demonstrated that α-gliadin genes evolved mainly by synonymous substitutions under strong purifying selection during the evolutionary process.
authors: College of Life Science, Capital Normal University, 100048, Beijing, China.
authors: J
authors: J
authors: Li
authors: S-L
authors: SL
authors: Wang
authors: M
authors: M
authors: Cao
authors: D-W
authors: DW
authors: Lv
authors: S
authors: S
authors: Subburaj
authors: X-H
authors: XH
authors: Li
authors: F J
authors: FJ
authors: Zeller
authors: S L K
authors: SL
authors: Hsam
authors: Y-M
authors: YM
authors: Yan
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D019143:Evolution, Molecular; D017343:Genes, Plant; D018745:Genome, Plant; D005903:Gliadin / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D006109:Poaceae / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment; D014908:Triticum / Q000235:genetics*
chemical_list: D005903:Gliadin