BPMP, Univ Montpellier, CNRS, INRA, SupAgro, Montpellier, France.
Int J Mol Sci. 2019 Feb 7;20(3):715. doi: 10.3390/ijms20030715.
As the main cation in plant cells, potassium plays an essential role in adaptive responses, especially through its involvement in osmotic pressure and membrane potential adjustments. K homeostasis must, therefore, be finely controlled. As a result of different abiotic stresses, especially those resulting from global warming, K⁺ fluxes and plant distribution of this ion are disturbed. The hormone abscisic acid (ABA) is a key player in responses to these climate stresses. It triggers signaling cascades that ultimately lead to modulation of the activities of K⁺ channels and transporters. After a brief overview of transcriptional changes induced by abiotic stresses, this review deals with the post-translational molecular mechanisms in different plant organs, in Arabidopsis and species of agronomical interest, triggering changes in K⁺ uptake from the soil, K⁺ transport and accumulation throughout the plant, and stomatal regulation. These modifications involve phosphorylation/dephosphorylation mechanisms, modifications of targeting, and interactions with regulatory partner proteins. Interestingly, many signaling pathways are common to K⁺ and Cl/NO3 counter-ion transport systems. These cross-talks are also addressed.
作为植物细胞中的主要阳离子，钾在适应反应中起着至关重要的作用，特别是通过参与渗透压和膜电位的调节。因此，必须精细地控制钾的动态平衡。由于不同的非生物胁迫，特别是由全球变暖引起的非生物胁迫，K⁺通量和植物对该离子的分布受到干扰。激素脱落酸（ABA）是应对这些气候胁迫的关键因素。它触发信号级联反应，最终导致 K⁺通道和转运蛋白活性的调节。在简要概述非生物胁迫诱导的转录变化后，本综述讨论了不同植物器官中，在拟南芥和农业相关物种中，引发从土壤中吸收 K⁺、K⁺在植物体内的运输和积累以及气孔调节变化的翻译后分子机制。这些修饰涉及磷酸化/去磷酸化机制、靶向修饰和与调节伙伴蛋白的相互作用。有趣的是，许多信号通路对 K⁺和 Cl/NO3 抗衡离子运输系统是共同的。这些串扰也得到了探讨。
