NADPH oxidase AtrbohD and AtrbohF function in ROS-dependent regulation of Na+/K+ homeostasis in Arabidopsis under salt stress
NADPH oxidase AtrbohD and AtrbohF function in ROS-dependent regulation of Na+/K+ homeostasis in Arabidopsis under salt stress
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NADPH氧化酶AtrbohD和AtrbohF在盐胁迫下拟南芥Na/K稳态ROS依赖性调节中的作用
DOI：
10.1093/jxb/err280
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发表时间：
2012-01-01
影响因子：
6.9
通讯作者：
Hao, Fushun
中科院分区：
文献类型：
--
作者：
Ma, Liya;Zhang, Huan;Hao, Fushun
维持细胞内Na+/K+平衡是植物在盐环境中生存的关键。然而，在盐胁迫下植物Na+/K+稳态的分子调控机制的知识在很大程度上是缺乏的。在本报告中，拟南芥双突变体atrbohD 1/F1和atrbohD 2/F2，其中AtrbohD和AtrbohF基因被破坏，活性氧（ROS）的产生被明显抑制，被发现是更敏感的NaCl处理比野生型（WT）和单一的无效突变体atrbohD 1和atrbohF 1植物。在盐胁迫下，两个双突变体幼苗的Na+含量显著高于WT、atrbohD 1和atrbohF 1，K+含量显著低于WT和atrbohF 1，Na+/K+比值显著高于WT和atrbohD 1。外源H_2O_2可部分逆转NaCl对双突变体Na ~+/K ~+比值的影响。预处理与二苯碘鎓氯化物，广泛使用的NADPH氧化酶抑制剂，明显提高Na+/K+比值在WT幼苗盐胁迫下。此外，NaCl抑制内向K+电流被逮捕，NaCl促进增加细胞质Ca 2+和质膜Ca 2+内流显着衰减atrbohD 1/F1植物。未观察到WT、atrbohD 1、atrbohF 1、atrbohD 1/F1和atrbohD 2/F2之间对渗透或氧化应激的敏感性存在显著差异。综上所述，这些结果强烈表明，由AtrbohD和AtrbohF产生的ROS作为信号分子调节Na+/K+稳态，从而提高拟南芥的耐盐性。
Maintaining cellular Na+/K+ homeostasis is pivotal for plant survival in saline environments. However, knowledge about the molecular regulatory mechanisms of Na+/K+ homeostasis in plants under salt stress is largely lacking. In this report, the Arabidopsis double mutants atrbohD1/F1 and atrbohD2/F2, in which the AtrbohD and AtrbohF genes are disrupted and generation of reactive oxygen species (ROS) is pronouncedly inhibited, were found to be much more sensitive to NaCl treatments than wild-type (WT) and the single null mutant atrbohD1 and atrbohF1 plants. Furthermore, the two double mutant seedlings had significantly higher Na+ contents, lower K+ contents, and resultant greater Na+/K+ ratios than the WT, atrbohD1, and atrbohF1 under salt stress. Exogenous H2O2 can partially reverse the increased effects of NaCl on Na+/K+ ratios in the double mutant plants. Pre-treatments with diphenylene iodonium chloride, a widely used inhibitor of NADPH oxidase, clearly enhanced the Na+/K+ ratios in WT seedlings under salt stress. Moreover, NaCl-inhibited inward K+ currents were arrested, and NaCl-promoted increases in cytosolic Ca2+ and plasma membrane Ca2+ influx currents were markedly attenuated in atrbohD1/F1 plants. No significant differences in the sensitivity to osmotic or oxidative stress among the WT, atrbohD1, atrbohF1, atrbohD1/F1, and atrbohD2/F2 were observed. Taken together, these results strongly suggest that ROS produced by both AtrbohD and AtrbohF function as signal molecules to regulate Na+/K+ homeostasis, thus improving the salt tolerance of Arabidopsis.