Melatonin improves rice salinity stress tolerance by NADPH oxidase-dependent control of the plasma membrane K+ transporters and K+ homeostasis
Melatonin improves rice salinity stress tolerance by NADPH oxidase-dependent control of the plasma membrane K+ transporters and K+ homeostasis
复制标题
褪黑激素通过 NADPH 氧化酶依赖性控制质膜 K 转运蛋白和 K 稳态来提高水稻盐胁迫耐受性
DOI：
10.1111/pce.13759
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发表时间：
2020-05-24
影响因子：
7.3
通讯作者：
Zhao, Quanzhi
中科院分区：
文献类型：
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作者：
Liu, Juan;Shabala, Sergey;Zhao, Quanzhi
本研究旨在揭示褪黑激素介导的植物盐胁迫缓解机制。电生理实验表明，褪黑激素降低盐诱导的K+外流（植物耐盐性的一个关键决定因素）的剂量和时间依赖性的方式和降低质膜K+渗透通道的敏感性羟基自由基。褪黑素的这些有益作用被NADPH氧化酶阻断剂DPI消除。转录组分析显示，褪黑激素诱导585（448上调和137下调）和59（54上调和5下调）差异表达基因（DEG）在根尖和成熟区，分别。在根尖中最显著的变化是褪黑激素诱导的呼吸爆发NADPH氧化酶（OsRBOHA和OsRBOHF）、钙调神经磷酸酶B样/钙调神经磷酸酶B样相互作用蛋白激酶（OsCBL/OsCIPK）和钙依赖蛋白激酶（OsCDPK）的表达增加。褪黑激素还增强钾转运蛋白基因（OsAKT 1，OsHAK 1和OsHAK 5）的表达。总之，这些结果表明，褪黑激素提高水稻耐盐性，使K+滞留在根中，而后者的过程是由褪黑激素清除羟基自由基和并发OsRBOHF依赖的活性氧信号所需的激活胁迫响应基因和增加表达的K+吸收转运蛋白在根尖。
This study aimed to reveal the mechanistic basis of the melatonin-mediated amelioration of salinity stress in plants. Electrophysiological experiments revealed that melatonin decreased salt-induced K+ efflux (a critical determinant of plant salt tolerance) in a dose- and time-dependent manner and reduced sensitivity of the plasma membrane K+-permeable channels to hydroxyl radicals. These beneficial effects of melatonin were abolished by NADPH oxidase blocker DPI. Transcriptome analyses revealed that melatonin induced 585 (448 up- and 137 down-regulated) and 59 (54 up- and 5 down-regulated) differentially expressed genes (DEGs) in the root tip and mature zone, respectively. The most noticeable changes in the root tip were melatonin-induced increase in the expression of several DEGs encoding respiratory burst NADPH oxidases (OsRBOHA and OsRBOHF), calcineurin B-like/calcineurin B-like-interacting protein kinase (OsCBL/OsCIPK), and calcium-dependent protein kinase (OsCDPK) under salt stress. Melatonin also enhanced the expression of potassium transporter genes (OsAKT1, OsHAK1, and OsHAK5). Taken together, these results indicate that melatonin improves salt tolerance in rice by enabling K+ retention in roots, and that the latter process is conferred by melatonin scavenging of hydroxyl radicals and a concurrent OsRBOHF-dependent ROS signalling required to activate stress-responsive genes and increase the expression of K+ uptake transporters in the root tip.