Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, Spain.
Mathematics and Informatics Center, The University of Tokyo, Tokyo, Japan.
Nat Plants. 2020 Apr;6(4):416-426. doi: 10.1038/s41477-020-0634-2. Epub 2020 Apr 13.
The circadian clock is synchronized by environmental cues, mostly by light and temperature. Explaining how the plant circadian clock responds to temperature oscillations is crucial to understanding plant responsiveness to the environment. Here, we found a prevalent temperature-dependent function of the Arabidopsis clock component EARLY FLOWERING 4 (ELF4) in the root clock. Although the clocks in roots are able to run in the absence of shoots, micrografting assays and mathematical analyses show that ELF4 moves from shoots to regulate rhythms in roots. ELF4 movement does not convey photoperiodic information, but trafficking is essential for controlling the period of the root clock in a temperature-dependent manner. Low temperatures favour ELF4 mobility, resulting in a slow-paced root clock, whereas high temperatures decrease movement, leading to a faster clock. Hence, the mobile ELF4 delivers temperature information and establishes a shoot-to-root dialogue that sets the pace of the clock in roots.
生物钟由环境线索同步，主要由光和温度。解释植物生物钟如何响应温度波动对于理解植物对环境的响应至关重要。在这里，我们发现拟南芥生物钟成分 EARLY FLOWERING 4 (ELF4) 在根生物钟中存在普遍的、依赖温度的功能。尽管根中的时钟在没有芽的情况下也能够运行，但微嫁接实验和数学分析表明，ELF4 从芽转移到根中来调节节律。ELF4 的运动不传递光周期信息，但运输对于以温度依赖的方式控制根时钟的周期是必不可少的。低温有利于 ELF4 的迁移，导致根时钟缓慢，而高温则降低了运动速度，导致时钟更快。因此，可移动的 ELF4 传递温度信息，并建立一个从芽到根的对话，为根中的时钟设定节奏。
