Nitric oxide synthase-dependent nitric oxide production is associated with salt tolerance in Arabidopsis
Nitric oxide synthase-dependent nitric oxide production is associated with salt tolerance in Arabidopsis
复制标题
DOI：
10.1104/pp.107.096842
复制
发表时间：
2007-05-01
期刊：
影响因子：
7.4
通讯作者：
Zhang, Wen-Hao
中科院分区：
文献类型：
--
作者：
Zhao, Min-Gui;Tian, Qiu-Ying;Zhang, Wen-Hao
一氧化氮（NO）是参与植物许多生理过程的关键分子。为了研究NO在拟南芥（Arabidopsis thaliana）耐盐性中的作用，研究了NaCl对体内NO合成酶（NOS）活性受损和内源NO水平降低的拟南芥野生型和突变型（Atnoa1）植株的影响。Atnoa1突变体植株的Na+ / K+比值高于野生型植株，这是由于NaCl处理增加了Na+的积累，减少了K+的积累。盐胁迫下，Atnoa1种子的萌发比野生型种子更敏感，野生型植株的成活率高于Atnoa1植株。在对照和盐胁迫下，Atnoa1植物的过氧化氢水平均高于野生型植物，表明Atnoa1比野生型植物更容易受到盐胁迫和氧化胁迫。用NOS抑制剂和NO清除剂处理野生型植株可降低内源NO水平，并增强nacl诱导的Na+ / K+比值升高。野生型植物在NaCl胁迫下，NOS活性受到抑制，NOA1蛋白数量减少，导致NO特异性荧光探针测定的内源NO水平下降。用硝普钠处理Atnoa1植株可以减弱NaCl诱导的Na+ / K+比值的升高。因此，这些发现提供了直接证据，支持nos依赖性NO生产的中断与拟南芥的耐盐性有关。
Nitric oxide (NO) has emerged as a key molecule involved in many physiological processes in plants. To characterize roles of NO in tolerance of Arabidopsis (Arabidopsis thaliana) to salt stress, effect of NaCl on Arabidopsis wild-type and mutant (Atnoa1) plants with an impaired in vivo NO synthase (NOS) activity and a reduced endogenous NO level was investigated. Atnoa1 mutant plants displayed a greater Na+ to K+ ratio in shoots than wild-type plants due to enhanced accumulation of Na+ and reduced accumulation of K+ when exposed to NaCl. Germination of Atnoa1 seeds was more sensitive to NaCl than that of wild-type seeds, and wild-type plants exhibited higher survival rates than Atnoa1 plants when grown under salt stress. Atnoa1 plants had higher levels of hydrogen peroxide than wild-type plants under both control and salt stress, suggesting that Atnoa1 is more vulnerable to salt and oxidative stress than wild-type plants. Treatments of wild-type plants with NOS inhibitor and NO scavenger reduced endogenous NO levels and enhanced NaCl-induced increase in Na+ to K+ ratio. Exposure of wild-type plants to NaCl inhibited NOS activity and reduced quantity of NOA1 protein, leading to a decrease in endogenous NO levels measured by NO-specific fluorescent probe. Treatment of Atnoa1 plants with NO donor sodium nitroprusside attenuated the NaCl- induced increase in Na+ to K+ ratio. Therefore, these findings provide direct evidence to support that disruption of NOS-dependent NO production is associated with salt tolerance in Arabidopsis.