Purpose

Different from most crops and forages, the xerophyte Pugionium cornutum can absorb high quantities of Cl⁻ and then efficiently transport them into shoots to enhance osmotic adjustment ability under salt stress. However, the molecular mechanism underlying long-distance Cl⁻ transport remains unclear. SLAH1 is crucial for root-to-shoot Cl⁻ transport in Arabidopsis only under non-saline conditions. This study aimed to evaluate the function of PcSLAH1 from P. cornutum in long-distance Cl⁻ transport under salt stress.

Methods

PcSLAH1 was cloned, its tissue and subcellular locations and expression patterns in response to salt treatments were analyzed. The effect of PcSLAH1 on ion accumulation and the expression of key genes involved in Na⁺ and Cl⁻ transport were investigated by ectopically overexpressing in Arabidopsis driven by a root stelar-specific promoter.

Results

PcSLAH1 was specifically expressed at root stelar cells and located on the plasma membrane. Opposing with AtSLAH1 in Arabidopsis, the relative expression level of PcSLAH1 in roots was significantly induced by high Cl⁻ treatments. The root stelar-specific expression of PcSLAH1 in Arabidopsis resulted in a significant increase in shoot Cl⁻ content under NaCl or KCl treatment. PcSLAH1 could coordinate with CLCg and NHX1 to regulate shoot Cl⁻ and Na⁺ homeostasis under salt treatment. In addition, the root stelar-specific expression of PcSLAH1 conferred a stronger long-distance transport ability of Cl⁻ than AtSLAH1.

Conclusions

PcSLAH1 functions in facilitating the long-distance transport of Cl⁻ and modulating shoot Na⁺ and Cl⁻ homeostasis under salt stress. The up-regulated expression of PcSLAH1 is conducive to salt tolerance of P. cornutum.

中文翻译：

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在盐胁迫下，SLAH1 参与了 Cl- 从根到芽的长距离运输

目的

与大多数农作物和牧草不同，旱生植物Pugionium cornutum可以吸收大量的 Cl ^-，然后将其高效地输送到枝条中，以增强盐胁迫下的渗透调节能力。^{然而，长距离Cl -}运输的分子机制仍不清楚。SLAH1仅在非盐碱条件下对拟南芥中从根到茎的 Cl ^{-运输至关重要。}本研究旨在评估来自 P.cornutum 的 PcSLAH1在盐胁迫下长距离 Cl ^{-运输中的功能。}

方法

克隆了PcSLAH1，分析了其组织和亚细胞位置以及响应盐处理的表达模式。通过根星状特异性启动子驱动的拟南芥异位过表达研究了PcSLAH1对离子积累和参与 Na ⁺和 Cl ^{-转运的关键基因表达的影响。}

结果

PcSLAH1 在根星状细胞中特异性表达并位于质膜上。与拟南芥中的AtSLAH1相反，高Cl ^-处理显着诱导了根中PcSLAH1的相对表达水平。PcSLAH1在拟南芥中的根星状特异性表达导致在NaCl 或 KCl 处理下枝条 Cl ^{-含量显着增加。}PcSLAH1可以与CLCg和NHX1协调以调节盐处理下的枝条 Cl ^-和 Na ⁺稳态。此外，PcSLAH1的根星特异表达^{赋予Cl -}比AtSLAH1更强的远距离传输能力。

结论

PcSLAH1的作用是促进 Cl ^-的长距离运输并调节盐胁迫下的芽 Na ⁺和 Cl ^-稳态。PcSLAH1的上调表达有利于P.cornutum的耐盐性。