PDF(Pubmed)
Abstract：
Members of the abscisic acid (ABA)-responsive element (ABRE) binding factor (ABF) and ABA-responsive element binding protein (AREB) families play essential roles in the regulation of ABA signaling pathway activity and shape the ability of plants to adapt to a range of stressful environmental conditions. To date, however, systematic genome-wide analyses focused on the ABF/AREB gene family in wheat are lacking. Here, we identified 35 ABF/AREB genes in the wheat genome, designated TaABF1-TaABF35 according to their chromosomal distribution. These genes were further classified, based on their phylogenetic relationships, into three groups (A-C), with the TaABF genes in a given group exhibiting similar motifs and similar numbers of introns/exons. Cis-element analyses of the promoter regions upstream of these TaABFs revealed large numbers of ABREs, with the other predominant elements that were identified differing across these three groups. Patterns of TaABF gene expansion were primarily characterized by allopolyploidization and fragment duplication, with purifying selection having played a significant role in the evolution of this gene family. Further expression profiling indicated that the majority of the TaABF genes from groups A and B were highly expressed in various tissues and upregulated following abiotic stress exposure such as drought, low temperature, low nitrogen, etc., while some of the TaABF genes in group C were specifically expressed in grain tissues. Regulatory network analyses revealed that four of the group A TaABFs (TaABF2, TaABF7, TaABF13, and TaABF19) were centrally located in protein-protein interaction networks, with 13 of these TaABF genes being regulated by 11 known miRNAs, which play important roles in abiotic stress resistance such as drought and salt stress. The two primary upstream transcription factor types found to regulate TaABF gene expression were BBR/BPC and ERF, which have previously been reported to be important in the context of plant abiotic stress responses. Together, these results offer insight into the role that the ABF/AREB genes play in the responses of wheat to abiotic stressors, providing a robust foundation for future functional studies of these genes.
摘要：
脱落酸（ABA）响应元件（ABRE）结合因子（ABF）和ABA响应元件结合蛋白（AREB）家族成员在ABA信号通路活性的调节中起着至关重要的作用，并塑造了植物适应一系列胁迫环境条件的能力。迄今为止,然而,缺乏针对小麦ABF/AREB基因家族的全基因组系统分析。这里,我们在小麦基因组中鉴定出35个ABF/AREB基因,根据其染色体分布命名为TaABF1-TaABF35。这些基因被进一步分类，基于它们的系统发育关系，分为三组（A-C），给定组中的TaABF基因表现出相似的基序和相似数量的内含子/外显子。这些TaABFs上游启动子区域的顺式元件分析揭示了大量的ABRE，在这三组中确定的其他主要元素不同。TaABF基因扩增的模式主要表现为异源多倍体化和片段复制，纯化选择在该基因家族的进化中起着重要作用。进一步的表达谱分析表明，来自A和B组的大多数TaABF基因在各种组织中高度表达，并在非生物胁迫暴露如干旱后上调。低温,低氮,等。,而C组中的一些TaABF基因在籽粒组织中特异性表达。调节网络分析显示，A组TaABFs中的四个（TaABF2，TaABF7，TaABF13和TaABF19）位于蛋白质-蛋白质相互作用网络的中心，这些TaABF基因中的13个由11个已知的miRNAs调控，在干旱和盐胁迫等非生物胁迫的抗性中起着重要作用。发现调节TaABF基因表达的两个主要上游转录因子类型是BBR/BPC和ERF,先前已报道在植物非生物胁迫响应的背景下很重要。一起,这些结果提供了深入了解ABF/AREB基因在小麦对非生物胁迫的反应中的作用，为这些基因的未来功能研究提供了坚实的基础。
