《植物生理学报》 2015, 51(11): 2006-2012

马蔺NHX基因的克隆与基因表达分析

郭强, 孟林^*, 李杉杉, 张琳, 毛培春, 田小霞

北京市农林科学院, 北京草业与环境研究发展中心, 北京100097

通信作者：孟；E-mail: menglin9599@sina.com；Tel: 010-51503345

摘　要：

液泡膜Na⁺/H⁺逆向转运蛋白NHX所特有的液泡Na⁺区域化功能, 在植物耐盐中发挥着极其重要的作用。以马蔺根中总RNA为模板, 利用同源克隆方法克隆得到一个NHX基因, 命名为IlNHX。序列分析表明该基因的开放阅读框为1 641 bp, 编码546个氨基酸, 与已知的植物NHX具有较高的同源性(>70%)。预测其蛋白质分子量为60 kDa, 等电点为6.67。实时定量PCR分析表明, 随着NaCl浓度的增加, 地上部和根中的IlNHX基因表达水平呈增加趋势, 且地上部中的表达量显著高于根部, 表明IlNHX基因的表达受到盐的诱导和调节。

关键词：马蔺; 液泡膜Na⁺/H⁺逆向转运蛋白; 表达; 耐盐

收稿：2015-09-01   修定：2015-10-30

资助：北京市自然科学基金项目(6142007和6152008)、北京市农林科学院科技创新能力建设专项(KJCX20140103)和北京市农林科学院草业中心人才培养基金项目。

Cloning of Iris lactea var. chinensis NHX and Analysis of Gene Expression

GUO Qiang, MENG Lin^*, LI Shan-Shan, ZHANG Lin, MAO Pei-Chun, TIAN Xiao-Xia

Beijing Research and Development Center for Grasses and Environment, Beijing Academy of Agriculture and forestry Science, Beijing 100097, China

Corresponding author: MENG Lin; E-mail: menglin9599@sina.com; Tel: 010-51503345

Abstract:

The tonoplast Na⁺/H⁺ antiporters (NHX) are involved in the compartmentalization of Na⁺ into vacuoles and also play critical roles in salt tolerance of plant. Total RNA was extracted from the roots of Iris lacteal var. chinensis to obtain an IlNHX by homology cloning. The open reading frame of IlNHX was 1 641 bp encoding 546 amino acids. The deduced amino acid sequence of IlNHX shared over 70% amino acid homology compared with other plants NHX. The protein was estimated to have a molecular weight of 60 kDa and isoelectric point of 6.67. Quantitative real-time PCR analysis showed that expression levels of IlNHX exhibited an increase trends in both shoots and roots with the increase of external NaCl concentrations, and its levels in shoots was significant higher than that of roots, indicating that the expression of IlNHX was induced and regulated by salt.

Key words: Iris lactea var. chinensis; tonoplast Na⁺/H⁺ antiporter; expression; salt tolerance