Heat shock transcription factors (Hsfs) play an important role in regulating heat stress response in plants. Our previous study found that there were 82 non-redundant Hsfs in wheat, 18 of which belonged to subclass A2. In this study, we cloned an A2 member, TaHsfA2-1, which encoded a protein of 346 amino acid residues in wheat. The fusion protein TaHsfA2-1-GFP was localized in the nucleus under normal growth conditions. TaHsfA2-1 was expressed in nearly all the measured tissues, most highly in mature leaves. The expression level of TaHsfA2-1 can be enhanced by heat stress, PEG stress, and signal molecules such as H2O2 and SA. Yeast cells transformed with TaHsfA2-1 improved thermotolerance compared to those with the empty vector. TaHsfA2-1-overexpressing Arabidopsis displayed a better growth state with more green leaves than wild-type seedlings after heat stress. Accordingly, the chlorophyll content and survival rate in the transgenic lines were higher than in the wild type, and relative conductivity in the transgenic lines was lower than in the wild type. Further research found that TaHsfA2-1-overexpressing Arabidopsis up-regulated the expression of some heat shock protein genes (Hsps) compared to wild type after heat stress. These results suggested that TaHsfA2-1 is a new gene that improves thermotolerance in plants by mediating the expression of Hsps. A functional gene was provided for molecular breeding in the subsequent research.

中文翻译：

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TaHsfA2-1，小麦幼苗耐热性的新基因：表征和功能作用

热休克转录因子（Hsfs）在调节植物热应激反应中起重要作用。我们之前的研究发现小麦中有 82 个非冗余 Hsfs，其中 18 个属于亚类 A2。在这项研究中，我们克隆了一个 A2 成员 TaHsfA2-1，它在小麦中编码了 346 个氨基酸残基的蛋白质。融合蛋白 TaHsfA2-1-GFP 在正常生长条件下定位于细胞核中。TaHsfA2-1 在几乎所有测量的组织中表达，在成熟叶中表达最高。TaHsfA2-1 的表达水平可以通过热应激、PEG 应激和信号分子如 H2O2 和 SA 增强。与空载体相比，用 TaHsfA2-1 转化的酵母细胞提高了耐热性。TaHsfA2-1 过表达的拟南芥在热应激后表现出比野生型幼苗更好的生长状态，具有更多的绿叶。因此，转基因品系的叶绿素含量和存活率高于野生型，而转基因品系的相对电导率低于野生型。进一步的研究发现，与热应激后的野生型相比，过表达 TaHsfA2-1 的拟南芥上调了一些热休克蛋白基因 (Hsps) 的表达。这些结果表明，TaHsfA2-1 是一种通过介导 Hsps 表达来提高植物耐热性的新基因。为后续的分子育种研究提供了一个功能基因。转基因品系的相对电导率低于野生型。进一步的研究发现，与热应激后的野生型相比，过表达 TaHsfA2-1 的拟南芥上调了一些热休克蛋白基因 (Hsps) 的表达。这些结果表明，TaHsfA2-1 是一种通过介导 Hsps 表达来提高植物耐热性的新基因。为后续的分子育种研究提供了一个功能基因。转基因品系的相对电导率低于野生型。进一步的研究发现，与热应激后的野生型相比，过表达 TaHsfA2-1 的拟南芥上调了一些热休克蛋白基因 (Hsps) 的表达。这些结果表明，TaHsfA2-1 是一种通过介导 Hsps 表达来提高植物耐热性的新基因。为后续的分子育种研究提供了一个功能基因。