title: Isolation, promoter analysis and expression profile of Dreb2 in response to drought stress in wheat ancestors.
abstract: Drought is one of the most important abiotic stresses, constraining crop production seriously. The dehydration responsive element binding proteins (DREBs) are important plant-specific transcription factors that respond to various abiotic stresses and consequently induce abiotic stress-related genes that impart stress endurance in plants. Wild species are naturally exposed to various abiotic stresses and potentially harbor suitable alleles through natural selection. In this study we isolated and characterized Dreb2 from Triticum urartu (GenBank: KF731664), Aegilops speltoides (GenBank: KF731665) and Aegilops tauschii (GenBank: KF731663), the A, B and D genome ancestors of bread wheat, respectively. Analysis of over 1.3 kb upstream region of the gene revealed the presence of several conserved cis-acting regulatory elements including ABA-responsive elements, low temperature responsive elements, and several light and environmental signaling related motifs potentially vindicate Dreb2 responses to environmental signals. Moreover, the gene exhibited an alternative splicing, conserved among orthologous genes in grasses, and produced a non-functional isoform due to splicing in an exon resulted frame-shift creating an early stop codon before the functional domain. The expression analysis of Dreb2 under normal and different levels of dehydration stress conditions indicated that the two active spliced isoforms are upregulated when the plant exposed to drought stress whereas the non-functional isoform is downregulated in severe drought.
authors.affiliation: Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy. Electronic address: elahe.tavakol@unimi.it.
authors.forename: Elahe
authors.initials: E
authors.lastname: Tavakol
authors.affiliation: University of Parma, Department of Food Science, Parco Area delle Scienze 49A, 43124 Parma, Italy.
authors.forename: Maria Luisa Savo
authors.initials: ML
authors.lastname: Sardaro
authors.affiliation: National Institute of Genetic Engineering and Biotechnology (NIGEB), 14965/161, Tehran, Iran.
authors.forename: J Vahid
authors.initials: JV
authors.lastname: Shariati
authors.affiliation: Università degli Studi di Milano, DISAA, Via Celoria 2, 20133 Milan.
authors.forename: Laura
authors.initials: L
authors.lastname: Rossini
authors.affiliation: Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy; University of Tuscia, Department of Agrobiology and Agrochemistry, Viterbo.
authors.forename: Enrico
authors.initials: E
authors.lastname: Porceddu
mesh_terms: D017398:Alternative Splicing; D001483:Base Sequence; D055864:Droughts; D019143:Evolution, Molecular; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D018745:Genome, Plant; D008969:Molecular Sequence Data; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D006109:Poaceae / Q000145:classification* / Q000235:genetics*; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms; D013312:Stress, Physiological; D059467:Transcriptome; D014908:Triticum / Q000235:genetics
chemical_list: D010940:Plant Proteins; D020033:Protein Isoforms
keywords: Dreb2; Drought; Expression; Promoter; Wheat ancestors