A prion-like domain in ELF3 functions as a thermosensor inArabidopsis
A prion-like domain in ELF3 functions as a thermosensor inArabidopsis
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DOI：
10.1038/s41586-020-2644-7
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发表时间：
2020-08-26
期刊：
影响因子：
64.8
通讯作者：
Wigge, Philip A.
中科院分区：
文献类型：
--
作者：
Jung, Jae-Hoon;Barbosa, Antonio D.;Wigge, Philip A.
植物拟南芥对不同温度的适应性是由其ELF 3蛋白进行液-液相分离的能力来调节的，这种能力依赖于蛋白的朊病毒样结构域。温度控制植物的生长和发育，气候变化已经改变了野生植物和作物的物候（1）。然而，植物感知温度的机制还不清楚。夜间复合体是一个主要的信号枢纽和植物昼夜节律钟的核心组成部分（2，3）。夜晚复合物作为温度响应性转录抑制因子，通过未知的机制为生长提供节律性和温度响应性（2，4 -6）。夜间复合物由EARLY FLOWER 3（ELF 3）（4，7），一种大的支架蛋白和温度传感的关键组分; ELF 4，一种小的α-螺旋蛋白;和LUX ARRYTHMO（LUX），一种将夜间复合物募集到转录靶点所需的DNA结合蛋白组成。ELF 3含有多聚谷氨酰胺（polyQ）重复序列（8-10），嵌入预测的朊病毒结构域（PrD）中。在这里，我们发现polyQ重复序列的长度与热响应相关。我们表明，ELF 3蛋白在植物中从炎热的气候，没有检测到的PrD，在高温下是活跃的，缺乏热响应。ELF 3的温度敏感性也受到ELF 4水平的调节，表明ELF 4可以稳定ELF 3的功能。在异源系统和异源系统中，ELF 3融合绿色荧光蛋白以PrD依赖的方式在几分钟内响应于较高的温度形成斑点。包含ELF 3 PrD的纯化片段在体外响应于温度升高可逆地形成液滴，表明这些性质反映了PrD赋予的直接生物物理响应。温度通过相变在活性和非活性状态之间快速转变ELF 3的能力代表了以前未知的热敏机制。
The adaptability of the plantArabidopsis thalianato different temperatures is regulated by the ability of its ELF3 protein to undergo liquid-liquid phase separation, in a manner that is dependent on the protein's prion-like domain.Temperature controls plant growth and development, and climate change has already altered the phenology of wild plants and crops(1). However, the mechanisms by which plants sense temperature are not well understood. The evening complex is a major signalling hub and a core component of the plant circadian clock(2,3). The evening complex acts as a temperature-responsive transcriptional repressor, providing rhythmicity and temperature responsiveness to growth through unknown mechanisms(2,4-6). The evening complex consists of EARLY FLOWERING 3 (ELF3)(4,7), a large scaffold protein and key component of temperature sensing; ELF4, a small alpha-helical protein; and LUX ARRYTHMO (LUX), a DNA-binding protein required to recruit the evening complex to transcriptional targets. ELF3 contains a polyglutamine (polyQ) repeat(8-10), embedded within a predicted prion domain (PrD). Here we find that the length of the polyQ repeat correlates with thermal responsiveness. We show that ELF3 proteins in plants from hotter climates, with no detectable PrD, are active at high temperatures, and lack thermal responsiveness. The temperature sensitivity of ELF3 is also modulated by the levels of ELF4, indicating that ELF4 can stabilize the function of ELF3. In bothArabidopsisand a heterologous system, ELF3 fused with green fluorescent protein forms speckles within minutes in response to higher temperatures, in a PrD-dependent manner. A purified fragment encompassing the ELF3 PrD reversibly forms liquid droplets in response to increasing temperatures in vitro, indicating that these properties reflect a direct biophysical response conferred by the PrD. The ability of temperature to rapidly shift ELF3 between active and inactive states via phase transition represents a previously unknown thermosensory mechanism.