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作 者 ：安 静1,2，侯 蕾1，孔祥强1,2，赵彦修1，张 慧1*

期 刊 ：西北植物学报 2012年 6期 页码：1106~1111

关键词：AtNHX5；液泡膜Na+/H+逆向转运蛋白；过量表达；耐盐性；拟南芥；

Keywords:AtNHX5 gene, vacuolar Na+/H+ antiporter, overexpression, salt tolerance, Arabidopsis thaliana,

摘 要 ：为了研究AtNHX5基因在植物耐盐中的作用，构建了植物过量表达载体pROKⅡ AtNHX5，并转化拟南芥。结果显示：（1）RT PCR检测表明，转基因拟南芥中AtNHX5基因的表达大幅提高。（2）对转基因纯合株系进行耐盐性分析显示，AtNHX5过量表达提高了植株在种子萌发和苗期的耐盐性。（3）转基因植株在盐处理下的干重、鲜重以及地上部分Na⁺、K⁺含量均高于野生型对照。在200 mmol/L NaCl处理下，以转基因株系a1 4为例，其地上部分单株鲜重、单株干重、K⁺含量分别是野生型的1.27、1.54、1.16倍，较野生型显著升高。研究表明，过量表达AtNHX5基因促进了盐胁迫下转基因植株对K⁺的吸收，转基因拟南芥的耐盐性明显提高。

Abstract:To investigate the role of AtNHX5 in plant salt resistance,the plant expression vector pROKⅡ AtNHX5 was constructed and introduced into Arabidopsis thaliana.RT PCR assay showed that:(1)AtNHX5 was over expressed in the transgenic lines.(2)Several transgenic homozygous lines and wild type plants were evaluated for salt stress tolerance,the results suggest that AtNHX5 transgenic plants were more tolerant to high NaCl concentrations during germination and seedling stages when compared with wild type plants.Under saline conditions,both fresh and dry weights of the transgenics as well as Na⁺ and K⁺ contents were much higher than that of wild type.To take transgenic plant a1 4 as an example,the shoot fresh weight,dry weight and K⁺ content were 1.27,1.54 and 1.16 fold,respectively compared with wild types under 200 mmol/L NaCl treatment,which were significantly higher than that in wild types.These results demonstrate that overexpression of AtNHX5 in Arabidopsis promoted the absorbing capacity of K⁺ and enhanced the salt tolerance of plants.

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