ZxSKOR is important for salinity and drought tolerance of Zygophyllum xanthoxylum by maintaining K+ homeostasis
ZxSKOR is important for salinity and drought tolerance of Zygophyllum xanthoxylum by maintaining K+ homeostasis
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ZxSKOR 通过维持钾稳态对霸王的盐度和耐旱性很重要
DOI：
10.1007/s10725-016-0157-z
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发表时间：
2016-11-01
影响因子：
4.2
通讯作者：
Wang, Suo-Min
中科院分区：
文献类型：
--
作者：
Hu, Jing;Ma, Qing;Wang, Suo-Min
K+作为一种重要的营养元素，在植物抗逆性中起着重要作用。中柱K+外向整流通道（SKOR）参与了K+向木质部的转运。霸王（Zygophyllum xanthoxylum）是一种多汁木本旱生植物，能够维持叶片中稳定的K+浓度，以适应盐和干旱环境。在这里，我们从Z.花椒ZxSKOR基因表达谱和Na+、K+积累量。用不同浓度的KCl和NaCl以及-0.5 MPa渗透胁迫处理花椒，以评估ZxSKOR对K+稳态的贡献。结果表明，ZxSKOR基因主要在根和茎中表达，而在叶中表达较少。当植物暴露于5-10 mM KCl时，其在根和茎中的表达水平显着增加，伴随着叶片中K+浓度的增加。此外，ZxSKOR在根中的表达量与地上部K+积累量呈正相关，在茎中的表达量与叶中K+积累量也呈正相关。在高盐（100-150 mM NaCl）和渗透胁迫（-0.5 MPa）下，根和茎中ZxSKOR的转录水平是在没有NaCl或渗透胁迫下生长的植物中的2.0-2.8倍。同时，在12-48 h的处理期间，在渗透胁迫加盐（-0.5 MPa +50 mM NaCl）下的根中ZxSKOR的表达水平显著高于单独的渗透胁迫（-0.5 MPa）下的表达水平。我们认为，根和茎中的ZxSKOR是协调的，介导长距离K+运输，并可能在Z的K+积累和体内平衡中发挥重要作用。盐胁迫和干旱胁迫对花椒的影响。
As an important nutrient element, K+ plays a crucial role in plant stress resistance. It was reported that the stelar K+ outward rectifying channel (SKOR) is involved in loading K+ into xylem for its transport from roots to shoots. Zygophyllum xanthoxylum, a succulent woody xerophyte, could maintain stable K+ concentration in leaves to adapt to salt and arid environments. Here we characterized ZxSKOR from Z. xanthoxylum, ZxSKOR expression patterns and Na+ and K+ accumulation in Z. xanthoxylum treated with various concentrations of KCl and NaCl and −0.5 MPa osmotic stress were investigated in order to assess the contribution of ZxSKOR to K+ homeostasis. The results showed that ZxSKOR was predominantly expressed in roots and stems rather than in leaves. Its expression levels in roots and stems increased significantly accompanied by an increase in K+ concentration in leaves when plants were exposed to 5–10 mM KCl. Moreover, a positive correlation was identified not only between ZxSKOR expression in roots and K+ accumulation in shoots, but also between ZxSKOR expression in stems and K+ accumulation in leaves. Transcription levels of ZxSKOR in roots and stems under high salinity (100–150 mM NaCl) and osmotic stress (−0.5 MPa) were 2.0–2.8 times those in plants grown in the absence of NaCl or osmotic stress. Concomitantly, the expression level of ZxSKOR in roots under osmotic stress plus salt (−0.5 MPa +50 mM NaCl) was significantly higher than that under osmotic stress (−0.5 MPa) alone during 12–48 h of treatment. We propose that ZxSKOR in roots and stems is well-coordinated to mediate long-distance K+ transport and perhaps plays an important role in K+ accumulation and homeostasis in Z. xanthoxylum under salt as well as drought stress.