Department of Plant Biology, Faculty of Biological Sciences, Tarbiat Modares University, P.O. Box 14115-154, Tehran, Iran.
Department of Plant Biology, Faculty of Biological Sciences, Tarbiat Modares University, P.O. Box 14115-154, Tehran, Iran.
Plant Physiol Biochem. 2018 Sep;130:139-147. doi: 10.1016/j.plaphy.2018.07.004. Epub 2018 Jul 3.
Plants respond to water stress through a variety of mechanisms, depending on metabolites preferences and their available resources. This work was performed to elucidate the cross-talk between signaling molecules (polyamines (PAs), hydrogen peroxide (HO) and nitric oxide (NO)), phenolic compounds and osmolytes (phenylethanoid glycosides (PhGs), phenolic acids, flavonoids, soluble sugars and amino acids) under water stress in Scrophularia striata plants. The results revealed that PAs, NO levels were enhanced in the plants, earlier in response to polyethylene glycol-induced water stress. The antioxidative mechanisms with increased activity of catalase (CAT), guaiacol peroxidase (GPX) and superoxide dismutase (SOD) and also phenylalanine ammonia-lyase (PAL), tyrosine ammonia-lyase (TAL), as key enzymes in phenolic pathway were deployed in response to the stress. Mannose, glucose, xylose/rhamnose which are involved in PhGs biosynthesis as well as in serving osmotic adjustment were modulated. The elevated content of arginine and methionine as PAs precursors and tyrosine and phenylalanine as PhGs precursors was enhanced by water stress and was significantly associated with PAs and PhGs accumulations. Metabolic profiling revealed new information about relationship between stress signal molecules; PAs, NO and HO, osmolytes (sugers, PhGs) and phenolic compounds which involved in the improvement of water stress tolerance in S. striata.
植物通过多种机制对水分胁迫做出响应，具体取决于代谢物的偏好及其可用资源。这项工作旨在阐明信号分子（多胺（PAs）、过氧化氢（HO）和一氧化氮（NO））、酚类化合物和渗透物（苯乙醇苷（PhGs）、酚酸、类黄酮、可溶性糖和氨基酸）之间的串扰在 Scrophularia striata 植物水分胁迫下的相互作用。结果表明，PAs、NO 水平在聚乙二醇诱导的水分胁迫下更早地增强。抗氧化机制通过增加过氧化氢酶 (CAT)、愈创木酚过氧化物酶 (GPX) 和超氧化物歧化酶 (SOD) 的活性以及苯丙氨酸氨裂解酶 (PAL)、酪氨酸氨裂解酶 (TAL) 的活性来应对压力，这些酶是酚类途径中的关键酶。甘露糖、葡萄糖、木糖/鼠李糖参与 PhGs 生物合成以及渗透调节的物质也被调节。作为 PAs 前体的精氨酸和蛋氨酸以及作为 PhGs 前体的酪氨酸和苯丙氨酸的含量升高，这是由水分胁迫引起的，并且与 PAs 和 PhGs 的积累显著相关。代谢组学分析揭示了有关应激信号分子之间关系的新信息；PAs、NO 和 HO、渗透物（糖、PhGs）和酚类化合物参与了 S. striata 对水分胁迫的耐受性的提高。
