【摘要】 小麦(Triticum aestivum)是我国重要的粮食作物之一，高温等非生物胁迫严重影响小麦的产量和品质，发掘与鉴定抗逆基因，可以为小麦抗逆育种提供候选基因和理论依据。热激蛋白(heat shock proteins, Hsps)是一类在应激条件下维持细胞功能的重要分子伴侣，是一类重要的耐热候选基因。本研究以耐热品种’平遥小白麦’的cDNA为模板，通过PCR扩增得到了小麦TaHsp17.9基因(GenBank No.MN684335)。该基因CDS全长474 bp，编码157个氨基酸。蛋白序列含有植物小热激蛋白(small heat shock protein, sHsp)特异性的α-晶体蛋白结构域(α-crystallin domain, ACD)。系统进化树分析表明，TaHsp17.9与二粒小麦(Triticum dicoccoides)的遗传距离最近。qPCR结果显示，TaHsp17.9基因在籽粒中表达量最高，在根中表达量最低。TaHsp17.9受高温和干旱胁迫诱导表达，其表达量分别在1和2 h达到峰值。高温胁迫下，该基因在耐热品种的表达量显著高于热敏感品种。亚细胞定位结果显示，TaHsp17.9蛋白定位在细胞质。对拟南芥(Arabidopsis thaliana) TaHsp17.9过表达株系进行耐热性鉴定，结果显示，TaHsp17.9过表达可以显著提高转基因拟南芥的耐热性。此外，基于STRING数据库筛选到10个可能与TaHsp17.9发生相互作用的候选互作蛋白。本研究结果为深入研究TaHsp17.9基因的功能提供了参考。更多还原

【Abstract】 Wheat(Triticum aestivum) is one of the most important food crops in China. High temperature and other abiotic stresses seriously affect the yield and quality of wheat. The discovery and identification of resistance genes can provide candidate genes and theoretical foundation for wheat stress resistance breeding.Heat shock proteins(Hsps) are crucial molecular chaperones that preserving cellular function under stress conditions and regarded as significant candidate genes for heat resistance. In this study, the TaHsp17.9 gene(GenBank No. MN684335) of wheat was amplified by PCR using the cDNA of the heat tolerance wheat variety ’Pingyao Xiaobaimai’ as a template. The total CDS length of TaHsp17.9 is 474 bp, encoding 157 amino acids. The protein sequence of TaHsp17.9 contains the specific α-crystallin domain(ACD) of plant small heat shock protein(sHsp). Phylogenetic tree analysis indicated that Hsp17.9 had the closest genetic distance to Triticum dicoccoides. qPCR results showed that the expression levels of TaHsp17.9 were highest in grain and lowest in root. The TaHsp17.9 was induced to express by high temperature and drought stress, and its expression level reached the peak at 1 and 2 h respectively. The expression level of TaHsp17.9 in heat tolerance varieties was significantly higher than that in heat sensitive varieties under the heat stress. The results of subcellular localization showed that TaHsp17.9 protein was localized in the cytoplasm. Identification of heat tolerance in the TaHsp17.9 overexpression strain of Arabidopsis thaliana, the result showed that,overexpression of TaHsp17.9 could significantly improve the heat tolerance of transgenic Arabidopsis thaliana.In addition, 10 candidate interacting proteins that might interact with Ta Hsp17.9 were obtained based on STRING database. This study provides a reference for further studying the function of TaHsp17.9 gene in wheat.更多还原