Cellular localization of Arabidopsis EARLY FLOWERING3 is responsive to light quality

第一作者：James Ronald

第一单位：英国约克大学

第一通讯：Seth J Davis

 Abstarct 

背景回顾：Circadian clocks facilitate the coordination of physiological and developmental processes to changing daily and seasonal cycles. A hub for environmental signaling pathways in the Arabidopsis (Arabidopsis thaliana) circadian clock is the evening complex (EC), a protein complex composed of EARLY FLOWERING3 (ELF3), ELF4, and LUX ARRYTHMO (LUX). Formation of the EC depends on ELF3, a scaffold protein that recruits the other components of the EC and chromatin remodeling enzymes to repress gene expression. Regulating the cellular distribution of ELF3 is thus an important mechanism in controlling its activity. 

生物钟促进植物生理活动与发育进程的协调，以适应不断变化的日周期和季节周期环境。拟南芥生物钟中环境信号通路的核心是由ELF3、ELF4和LUX组成的“夜晚复合体”EC（Evening Complex）。EC的形成依赖于ELF3蛋白，该蛋白是一个支架蛋白，能够招募EC复合体中的其它组分和染色质重塑酶以抑制基因的表达。因此，调控ELF3在细胞层面的分布是控制其活性的重要机制。

结果1-红光和蓝光竞争影响ELF蛋白的细胞定位：Here, we determined that the cellular and sub-nuclear localization of ELF3 is responsive to red (RL) and blue light and that these two wavelengths have apparently competitive effects on where in the cell ELF3 localizes. 

本文中，作者揭示了ELF3在细胞和亚核层面的定位是响应于红光和蓝光的，并且这两个波长对ELF3在细胞中的定位有明显的竞争效应。

结果2-红光控制的ELF3蛋白定位依赖于PhyB：We further characterized the RL response, revealing that at least two RL pathways influence the cellular localization of ELF3. One of these depends on the RL photoreceptor phytochrome B (phyB), while the second is at least partially independent of phyB activity. 

作者进一步研究了红光响应，发现至少两个红光途径会影响ELF3的细胞定位。其中一个依赖于红光受体phyB，而另外一个至少部分独立于phyB活性。

结果3-ELF3作用晨间基因的红光敏感性：Finally, we investigated how changes in the cellular localization of ELF3 are associated with repression of EC target-gene expression. Our analyses revealed a complex effect whereby ELF3 is required for controlling RL sensitivity of morning-phased genes, but not evening-phased genes.

最终，作者研究了ELF3细胞定位的改变是如何与EC靶向基因表达的抑制相关联的。作者的研究发现ELF3作用于控制晨间阶段基因的红光敏感性，但是并不作用于晚间基因。

结论：Together, our findings establish a previously unknown mechanism through which light signaling influences ELF3 activity.

综上，本文的研究建立了一个光信号转导介导的ELF3蛋白活性控制的分子机制。

** Seth J Davis **

doi: https://doi.org/10.1093/plphys/kiac072

Journal: Plant Physiology​

Published date: February 22, 2022