Department of Plant Molecular Physiology, Faculty of Biological Sciences, University of Wrocław, Kanonia 6/8, 50-328 Wrocław, Poland.
Cells. 2023 Sep 13;12(18):2263. doi: 10.3390/cells12182263.
When plants are exposed to environmental stress, their growth is inhibited. Under such conditions, controlled inhibition of growth is beneficial for plant survival. Jasmonic acid (JA) is a well-known phytohormone that limits plant growth, which has been confirmed in several species. However, its role in cucumber seedlings has not yet been comprehensively investigated. For this reason, we aimed to determine the involvement of JA in the regulation of proteins crucial for growth including plasma membrane proton pump (PM H-ATPase), PM nitrate transporters, and nitrate reductase (NR). Treatment of cucumber seedlings with JA not only limited their growth but also increased the HO content in their roots. The main sources of ROS generated for signalling purposes are PM NADPH oxidase (RBOH) and superoxide dismutase (SOD). Exposure of seedlings to JA induced the expression of some and SOD encoding genes, suggesting that ROS signalling can be activated by JA. As a consequence of JA exposure, the activity of all analysed proteins was inhibited and the expression of their genes was modified. The results indicate that reduction of PM H-ATPase activity and the related decrease in nitrate uptake and assimilation are responsible for the root growth retardation of JA-treated plants.
当植物暴露在环境压力下时，它们的生长会受到抑制。在这种情况下，对生长的可控抑制有利于植物的生存。茉莉酸（JA）是一种众所周知的植物激素，它限制植物的生长，这已在几种物种中得到证实。然而，它在黄瓜幼苗中的作用尚未得到全面研究。出于这个原因，我们旨在确定 JA 是否参与调节包括质膜质子泵（PM H-ATPase）、PM 硝酸盐转运体和硝酸还原酶（NR）在内的对生长至关重要的蛋白质的调控。用 JA 处理黄瓜幼苗不仅限制了它们的生长，还增加了它们根部的 HO 含量。用于信号转导的 ROS 的主要来源是质膜 NADPH 氧化酶（RBOH）和超氧化物歧化酶（SOD）。幼苗暴露于 JA 诱导了一些编码基因的表达，表明 JA 可以激活 ROS 信号转导。JA 暴露后，所有分析的蛋白质的活性都受到抑制，其基因的表达也发生了改变。研究结果表明，PM H-ATPase 活性的降低以及相关的硝酸盐摄取和同化的减少是 JA 处理植物根系生长迟缓的原因。
