《植物生理学报》 2021, 57(3): 681-691

香蕉NHX基因家族的鉴定及表达分析

徐亚¹，滕梦鑫¹，何岳东²，乔飞³，李新国^1,*

¹海南大学园艺学院, 海口570228；²湖南农业大学园艺学院, 长沙410128；³中国热带农业科学院热带作物品种资源研究所, 海口570100

通信作者：李新国；E-mail: lixinguo13@163.com

摘　要：

NHX是Na⁺(K⁺)/H⁺的逆向转运蛋白, 具有Na⁺/H⁺ exchange (PF00999)蛋白结构域, 广泛存在于多种生物中, 主要参与植物响应盐胁迫过程中离子平衡的重建。本研究从香蕉(Musa spp.)基因组数据库中鉴定了NHX基因家族, 并进行生物信息学分析及盐胁迫下香蕉NHX基因的表达分析。结果表明, 鉴定到香蕉11个NHX家族基因, 分别分布在7条染色体上; 大部分MaNHXs基因外显子(14~22)为14个, MaNHX6含有22个外显子; 理化性质分析发现大部分MaNHXs蛋白等电点大于8, 蛋白质分子质量为57~62 kDa; 亚细胞定位预测表明MaNHXs均定位在液泡; 与拟南芥(Arabidopsis thaliana)、水稻(Oryza sativa)的NHX蛋白一起构建的系统发育树分为2个聚类组。通过烟草叶片亚细胞定位分析表明, MaNHX5蛋白定位于液泡膜。qRT-PCR结果表明香蕉幼苗在200 mmol·L^–1 NaCl胁迫下, MaNHXs在根、假茎和叶片中均有表达且在不同时间表达差异显著。

关键词：香蕉; NHX基因家族; 盐胁迫; 亚细胞定位; qRT-PCR

收稿：2020-09-23   修定：2021-01-24

资助：国家自然科学基金(31760549)

Identifcation and expression analysis of NHX genes family in banana

XU Ya¹, TENG Mengxin¹, HE Yuedong², QIAO Fei³, LI Xinguo^1,*

¹Institute of Horticulture, Hainan University, Haikou 570228, China 2; ²Institute of Horticulture, Hunan Agriculture University, Changsha 410128, China; ³Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 570100, China

Corresponding author: LI Xinguo; E-mail: lixinguo13@163.com

Abstract:

NHX is an antiporter of Na⁺(K⁺)/H⁺ with a protein domain of Na⁺/H⁺ exchange (PF00999). It is widely present in a variety of organisms and is mainly involved in the restoration of ion balance in the process of plant response to salt stress. This research carried out the gene identifcation of the NHX gene family of bananas (Musa spp.), bioinformatics analysis and analysis of banana NHX genes expression under salt stress. 11 NHX genes were identifed from the banana genome database, and most of them were found in physical and chemical properties. The isoelectric point of most MaNHXs protein is greater than 8, protein molecular mass is 57-62 kDa, subcellular localization prediction showed that MaNHXs protein are located in vacuoles. The phylogenetic tree constructed together with the NHX proteins of Arabidopsis and rice is divided into two cluster groups. Most MaNHXs gene exons (14-22) are 14, and MaNHX6 contains 22 exons. Subcellular localization experiments of tobacco leaves showed that the MaNHX5 protein was localized in the tonoplast. The results of qRT-PCR showed that MaNHXs were expressed in banana seed ling roots, pseudostems and leaves under 200 mmol·L^–1 NaCl salt stress. The above results provide refer ences for in-depth study of the functions of the MaNHXs and the mechanism of slat tolerance to banana

Key words: Musa spp.; NHX gene family; salt stress; subcellular localization; fluorescent quantitative