Rapid and reversible root growth inhibition by TIR1 auxin signalling

First author: Matyáš Fendrych; Affiliations: Institute of Science and Technology (奥地利科学技术研究所): Klosterneuburg, Austria

Corresponding author: Jiří Friml 

The phytohormone auxin is the information carrier in a plethora of developmental and physiological processes in plants. It has been firmly established that canonical, nuclear auxin signalling acts through regulation of gene transcription. Here, we combined microfluidics (微流控技术), live imaging (活细胞成像), genetic engineering and computational modelling to reanalyse the classical case of root growth inhibition by auxin. We show that Arabidopsis roots react to addition and removal of auxin by extremely rapid adaptation of growth rate. This process requires intracellular auxin perception but not transcriptional reprogramming. The formation of the canonical TIR1/AFB–Aux/IAA co-receptor complex is required for the growth regulation, hinting (暗示) to a novel, non-transcriptional branch of this signalling pathway. Our results challenge the current understanding of root growth regulation by auxin and suggest another, presumably non-transcriptional, signalling output of the canonical auxin pathway.

植物激素生长素是许多植物发育和生理进程的信息载体。已有的研究认为核生长素信号通过对基因转录的调控来发挥作用。本文结合了微流控技术、活体成像、遗传工程及计算建模等方法重新分析了生长素抑制根生长的现象。作者发现拟南芥的根对添加或去除生长素的反应表现出极其迅速的根生长适应性。该过程的确需要细胞内对于生长素的感知，但并不需要转录重编程。研究显示TIR1/AFB–Aux/IAA共受体复合物对于生长调控是必需的，暗示着该信号通路一个新的、非转录的分枝。本文的结果挑战了现有的对于生长素调控根生长经典认知，提出了生长素信号通路通过一个非转录途径介导根的生长发育。

通讯：Jiří Friml (https://ist.ac.at/research/research-groups/friml-group/)

研究方向：生长素的极性运输；细胞极性与极性靶向；细胞内吞与再循环；信号的非转录调控机制。

doi: https://doi.org/10.1111/tpj.14005

Journal: Nature Plants

Published date: 25 June, 2018

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