PDF(Pubmed)
Abstract：
Plants exposed to incidences of excessive temperatures activate heat-stress responses to cope with the physiological challenge and stimulate long-term acclimation1,2. The mechanism that senses cellular temperature for inducing thermotolerance is still unclear3. Here we show that TWA1 is a temperature-sensing transcriptional co-regulator that is needed for basal and acquired thermotolerance in Arabidopsis thaliana. At elevated temperatures, TWA1 changes its conformation and allows physical interaction with JASMONATE-ASSOCIATED MYC-LIKE (JAM) transcription factors and TOPLESS (TPL) and TOPLESS-RELATED (TPR) proteins for repressor complex assembly. TWA1 is a predicted intrinsically disordered protein that has a key thermosensory role functioning through an amino-terminal highly variable region. At elevated temperatures, TWA1 accumulates in nuclear subdomains, and physical interactions with JAM2 and TPL appear to be restricted to these nuclear subdomains. The transcriptional upregulation of the heat shock transcription factor A2 (HSFA2) and heat shock proteins depended on TWA1, and TWA1 orthologues provided different temperature thresholds, consistent with the sensor function in early signalling of heat stress. The identification of the plant thermosensors offers a molecular tool for adjusting thermal acclimation responses of crops by breeding and biotechnology, and a sensitive temperature switch for thermogenetics.
摘要：
暴露于温度过高的植物会激活热应激反应，以应对生理挑战并刺激长期适应1,2。感知细胞温度诱导耐热性的机制仍不清楚3。在这里，我们表明TWA1是一种温度感应转录共调节因子，是拟南芥基础和获得性耐热性所必需的。在高温下,TWA1改变其构象并允许与Jasmonate相关的MYC样（JAM）转录因子和TOPLESS（TPL）和TOPLESS相关（TPR）蛋白物理相互作用，用于阻遏复合物组装。TWA1是一种预测的内在无序蛋白，通过氨基末端高度可变区具有关键的热感作用。在高温下,TWA1积累在核子结构域中，与JAM2和TPL的物理相互作用似乎仅限于这些核子结构域。热激转录因子A2（HSFA2）和热激蛋白的转录上调依赖于TWA1，TWA1直向同源物提供不同的温度阈值，与早期热应力信号中的传感器功能一致。植物热传感器的识别提供了一种分子工具，用于通过育种和生物技术调节作物的热适应反应。和热遗传学的敏感温度开关。
