作物学报2018，Vol.44Issue(1)：53-62,10.DOI:10.3724/SP.J.1006.2018.00053
小麦热激转录因子基因TaHsfB2d的克隆和特性及其对耐热性的调控
Cloning and Characterization of Heat Shock Transcription Factor Gene TaHsfB2d and Its Regulating Role in Thermotolerance
摘要
Abstract
Heat shock transcription factors (Hsfs) are key components of heat shock signal transduction pathways involved in the activation of Hsp genes in response to heat stress in plants. There are at least 56 members in wheat Hsf family. Eleven of them belong to class B, among which 5 members belong to subclass B2. In this study, TaHsfB2d was isolated from wheat (Triticum aestivum L.) young leaves treated by heat shock at 37 ℃for 1.5 h using homologous cloning methods. Sequence analysis showed that the coding sequence (CDS) of TaHsfB2d was 1191 bp encoding a protein of 396 amino acids. The amino acid sequence analysis demonstrated that TaHsfB2d contained a DNA-binding domain (DBD) and nuclear localization signal (NLS). TaHsfB2d protein sequence shared 90％, 85％, and 80％ identities with the proteins from predicted protein of Hordeum vulgare, HsfB2c of Hordeum vulgare and Brachypodium distachyon, respectively. The qRT-PCR results showed that TaHsfB2d was expressed in multiple tissues and organs of wheat, and the relative expression level of TaHsfB2d was higher in roots at anthesis stage. TaHsfB2d was up-regulated by 37℃heat shock (HS), salicylic acid (SA) and H2O2 in leaves. Furthermore, HS significantly enhanced the expression of TaHsfB2d pretreated with SA or H2O2, the up-regulation expression of TaHsfB2d by HS was significantly inhibited by the combined treatment of 150 μmol L–1 DPI and 20 mmol L–1 DMTU, and the up-regulation expression by SA was completely inhibited. Through transient reporter assay with onion (Allium cepa L.) epidermal cells, we found that TaHsfB2d localized in the nuclei. Yeast overexpressing TaHsfB2d showed stronger growth potential than the control cells overexpressing pYES2 after HS at 50℃for 45 min, and overexpression of TaHsfB2d had no effect on the growth and development of yeast cells. The results re-vealed that TaHsfB2d perhaps plays a key role in regulating the response to HS through SA signal pathway in plants, which was dependent on existence of H2O2. These results will provide theoretical basis for analysing biological functions and regulating mechanism of TaHsfB2d further.关键词
小麦/TaHsfB2d/定量表达/亚细胞定位/耐热性Key words
wheat/TaHsfB2d/subcelullar-localization/quantitative expression/thermotolerance引用本文复制引用
赵立娜,刘子会,段硕楠,张园园,李国良,郭秀林..小麦热激转录因子基因TaHsfB2d的克隆和特性及其对耐热性的调控[J].作物学报,2018,44(1):53-62,10.基金项目
本研究由河北省自然科学基金重点项目(C2016301085), 河北省现代农业科技创新工程项目(2017038997, F17C10006), 河北省财政专项(494-0402-JBN-VT68)和河北省高层次人才项目(A201500130)资助.This study was supported by the Key Project of Natural Science Foundation of Hebei Province (C2016301085), the Technological Innovation Project of Modern Agriculture of Hebei Province (2017038997, F17C10006), the Key Research Project of Hebei Province (494-0402-JBN-VT68), and the High-level Talent Project of Hebei Province (A201500130). （C2016301085）
