Transcriptomic Identification of Wheat AP2/ERF Transcription Factors and Functional Characterization of in Response to Drought and Salinity Stresses.

AP2/ERF (APETALA2/ethylene responsive factor) is a family of plant-specific transcription factors whose members are widely involved in many biological processes, such as growth, development, and biotic and abiotic stress responses. Here, 20 genes were identified based on wheat RNA-seq data before and after drought stress, and classified as AP2, ERF, DREB, and RAV. The analysis of gene structure revealed that about 85% of family members had lost introns, which are presumed to have been lost during the formation and evolution of the wheat genome. The expression of 20 family genes could be verified by qRT-PCR, which further supported the validity of the RNA-seq data. Subsequently, subcellular localization and transcriptional activity experiments showed that the ERF proteins were mainly located in the nucleus and were self-activating, which further supports their functions as transcription factors. Furthermore, we isolated a novel gene induced by drought, salt, and cold stresses and named it . overexpression increased sensitivity to drought and salt stresses in , which was supported by physiological and biochemical indices. Moreover, the expression of stress- and antioxidant-related genes was downregulated in -overexpressing plants. Overall, these results contribute to the further understanding of the gene function in wheat.