Abstract：Abscisic acid (ABA) responsive element binding factors/abscisic acid responsive element binding proteins/abscisic acid insensitive 5 (ABF/AREB/ABI5) belongs to the basic leucine zipper (bZIP) transcription factors A subfamily, which participate in ABA signaling pathway by regulating the expression of downstream genes, and thereby affect the plant growth and development, as well as in response to abiotic stress. In this study, the members of the ABF/AREB/ABI5 subfamily were identified in the whole genome of wheat (Triticum aestivum), and the phylogenetic relationship, physical and chemical properties, gene structure, gene replication, cis-acting elements of promoters and the expression pattern of wheat TaABFs were analyzed. The results showed that a total of 36 TaABFs were identified in wheat, which were distributed on all chromosomes except 7B and there were tandem duplication and fragment duplication events on the Ⅲ homologous group. The coding region of wheat TaABF proteins were 672~1 191 bp in length, and their isoelectric point were 5.22~9.93, all of which were hydrophilic proteins. According to phylogenetic analysis, TaABFs were divided into 3 groups, and in each group, the TaABFs showed high similarity in structure, conserved motifs and physicochemical properties. The promoter analysis of TaABFs indicated that there were a large number of cis-acting elements in response to hormones and abiotic stresses in their promoters. Transcriptome expression pattern analysis showed that the TaABF genes expressed differentially in different tissues and developmental stages, most of which were highly expressed during seed development. The TaABF genes also showed different responses to drought, salt and low temperature stress, and the TaABF genes in group Ⅰ homologous to the Arabidopsis AREB/ABF subfamily were up-regulated under both drought and salt stress. Further expression analysis of TaABF genes in Group Ⅰ by qPCR showed that, under ABA treatment, TaABF18 was up-regulated, while TaABF17 and TaABF19 were significantly down-regulated. TaABF17, TaABF18 and TaABF19 were all significantly up-regulated under drought and salt stress. These results provide basic information for further study on the resistance function of TaABFs in wheat.
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