Meng Xiangzhao, Zhao Baihui, Li Mingyue, Liu Ran, Ren Qianqian, Li Guoliang, Guo Xiulin
Institute of Biotechnology and Food Science, Hebei Academy of Agriculture and Forestry Sciences/Plant Genetic Engineering Center of Hebei Province, Shijiazhuang, China.
College of Life Sciences, Hebei Normal University, Shijiazhuang, China.
Front Plant Sci. 2022 Jun 27;13:922561. doi: 10.3389/fpls.2022.922561. eCollection 2022.
Heat shock transcription factor (Hsf) exists widely in eukaryotes and responds to various abiotic stresses by regulating the expression of downstream transcription factors, functional enzymes, and molecular chaperones. In this study, , a heat shock transcription factor belonging to A2 subclass, was cloned from wheat () and its function was analyzed. encodes a protein containing 368 amino acids and has the basic characteristics of Hsfs. Multiple sequence alignment analysis showed that TaHsfA2-13 protein had the highest similarity with TdHsfA2c-like protein from , which reached 100%. The analysis of tissue expression characteristics revealed that was highly expressed in root, shoot, and leaf during the seedling stage of wheat. The expression of could be upregulated by heat stress, low temperature, HO, mannitol, salinity and multiple phytohormones. The TaHsfA2-13 protein was located in the nucleus under the normal growth conditions and showed a transcriptional activation activity in yeast. Further studies found that overexpression of in Col-0 or mutant results in improved tolerance to heat stress, HO, SA and mannitol by regulating the expression of multiple heat shock protein () genes. In summary, our study identified from wheat, revealed its regulatory function in varieties of abiotic stresses, and will provide a new target gene to improve stress tolerance for wheat breeding.
热激转录因子（Hsf）广泛存在于真核生物中，通过调节下游转录因子、功能酶和分子伴侣的表达来响应各种非生物胁迫。在本研究中，从普通小麦（Triticum aestivum）中克隆了一个属于A2亚类的热激转录因子，并对其功能进行了分析。TaHsfA2-13编码一个含有368个氨基酸的蛋白质，具有热激转录因子的基本特征。多序列比对分析表明，TaHsfA2-13蛋白与来自粗山羊草（Aegilops tauschii）的TdHsfA2c-like蛋白相似度最高，达到100%。组织表达特性分析显示，TaHsfA2-13在小麦幼苗期的根、茎和叶中高表达。TaHsfA2-13的表达可被热胁迫、低温、过氧化氢（H₂O₂）、甘露醇、盐度和多种植物激素上调。TaHsfA2-13蛋白在正常生长条件下位于细胞核中，并在酵母中表现出转录激活活性。进一步研究发现，在拟南芥（Arabidopsis thaliana）Col-0或突变体中过表达TaHsfA2-13可通过调节多个热激蛋白（HSP）基因的表达来提高对热胁迫、H₂O₂、水杨酸（SA）和甘露醇的耐受性。综上所述，我们的研究从普通小麦中鉴定出TaHsfA2-13，揭示了其在多种非生物胁迫中的调控功能，为小麦育种提高胁迫耐受性提供了一个新的靶基因。
