Data from: Time of day prioritizes the pool of translating mRNAs in response to heat stress

The circadian clock helps organisms to anticipate and coordinate gene regulatory responses to changes in environmental stimuli. Under growth limiting temperatures, time of day modulates the accumulation of polyadenylated mRNAs. In response to heat stress, plants will conserve energy and selectively translate mRNAs. How the clock and/or time of day regulates polyadenylated mRNAs bound by ribosomes in response to heat stress is unknown. In-depth analysis of Arabidopsis thaliana translating mRNAs found that time of day gates the response of approximately one-third of the circadian regulated heat responsive translatome. Specifically, time of day and heat stress interact to prioritize the pool of mRNAs in cue to be translated. For a subset of mRNAs, we observed a stronger gated response during the day, and preferentially before the peak of expression. We propose previously overlooked transcription factors (TFs) as regulatory nodes and show that the clock plays a role in the temperature response for select TFs. When the stress was removed, the redefined priorities for translation recovered within one-hour, though slower recovery was observed for abiotic stress regulators. Through hierarchical network connections between clock genes and prioritized TFs, our work provides a framework to target key nodes underlying heat stress tolerance throughout the day.生物钟（circadian clock）能够帮助生物体预判环境刺激变化，并协调基因调控应答反应。在生长受限温度条件下，当日节律会调控多聚腺苷酸化信使RNA（polyadenylated mRNAs）的积累水平。当遭遇热胁迫时，植物会节约能量并选择性翻译信使RNA。目前尚不明确生物钟和/或当日节律如何调控热胁迫应答过程中与核糖体结合的多聚腺苷酸化信使RNA。对拟南芥（Arabidopsis thaliana）翻译中信使RNA的深度分析显示，当日节律门控调控约三分之一受生物钟调控的热应答翻译组（translatome）的应答反应。具体而言，当日节律与热胁迫相互作用，为待翻译的信使RNA池确立翻译优先级。针对部分信使RNA，我们观察到日间的门控调控效应更强，且优先出现在表达峰值之前。我们提出此前被忽视的转录因子（transcription factors, TFs）可作为调控节点，并证实生物钟会参与部分转录因子的温度应答过程。当胁迫解除后，重新确立的翻译优先级可在1小时内恢复，但非生物胁迫调控因子的恢复速度相对较慢。通过生物钟基因与确立优先级的转录因子之间的层级网络关联，本研究构建了一个可靶向调控全天热胁迫耐受性关键节点的研究框架。