长叶红砂RtKCO1基因的克隆及功能分析  

Isolation and functional analysis of RtKCO1 from Reaumuria trigyna

作　　者：李宁宁 程佳敏 魏磊[1] 李国龙[1] 孙亚卿[1] LI Ningning;CHENG Jiamin;WEI Lei;LI Guolong;SUN Yaqing(College of Agronomy,Inner Mongolia Agricultural University,Hohhot 010019,China)

机构地区：[1]内蒙古农业大学农学院,呼和浩特010019

出　　处：《植物生理学报》2025年第2期134-146,共13页Plant Physiology Journal

基　　金：内蒙古自治区高等学校青年科技英才支持项目(NJYT23088);国家自然科学基金(32060506和32060507);现代农业产业技术体系(CARS-17-0201);内蒙古自然科学基金(2023MS03015和2023MS03030)。

摘　　要：长叶红砂是一种古老的野生泌盐盐生植物,具有极强的耐盐性。外向整流型钾离子通道蛋白(KCO)在植物响应盐胁迫时发挥重要作用,但其在泌盐盐生植物中的功能研究还鲜有报道。为调查长叶红砂RtKCO1的功能,本研究基于转录组数据分离了该基因,并进行生物信息学分析;调查了该基因在不同浓度Na Cl和KCl胁迫下的表达模式,解析了该基因编码蛋白在酵母和拟南芥中的Na^(+)/K^(+)离子转运特性。结果表明:Rt KCO1基因包含有1 077 bp的开放阅读框,编码358个氨基酸。该基因能够被200 mmol·L^(-1) Na Cl和10 mmol·L^(-1) KCl快速诱导表达。转Rt KCO1基因酵母对高Na^(+)和高K^(+)耐受,RtKCO1在外部高Na^(+)和高K^(+)环境下分别介导Na^(+)/K^(+)的共转运和K^(+)的转运。转基因拟南芥则对高Na^(+)和低K^(+)耐受,归因于Rt KCO1能够维持Na^(+)/K^(+)稳态,改善渗透调节和抗氧化调节能力。以上结果初步阐明了Rt KCO1基因在调控植物耐盐中的作用机制,为植物耐盐性遗传改良提供重要候选基因。Reaumuria trigyna is an ancient feral recretohalophyte with strong salt tolerance.The outward rectifying potassium channel protein(KCO)plays an important role in plant response to salt stress,but its function in recretohalophyte is rarely reported.To investigate the function of the RtKCO1 from R.trigyna,this gene was isolated based on transcriptome data and subjected to bioinformatics analysis.The expression patterns of RtKCO1 under different concentrations of NaCl and KCl stress were investigated,and the Na^(+)/K^(+)transport characteristics of RtKCO1 in yeast and Arabidopsis were analyzed.The results show that RtKCO1 contains an open reading frame of 1077 bp,encoding 358 amino acids,which can be rapidly induced to express by 200 mmol·L^(−1) NaCl and 10 mmol·L^(−1) KCl.Yeast cell expressing RtKCO1 exhibits tolerance to high Na^(+)and high K^(+).RtKCO1 mediates the co-transport of Na^(+)/K^(+)under external high Na^(+)conditions,while it only mediates the transport of K^(+)under high K^(+)environment.Transgenic Arabidopsis exhibits tolerance to high Na^(+)and low K^(+),which may be attributed to the ability of RtKCO1 to maintain Na^(+)/K^(+)homeostasis,improving osmotic and antioxidant regulatory abilities.These results elucidated the mechanism of RtKCO1 in regulating plant salt tolerance,providing important candidate genes for genetic improvement of plant salt tolerance.

关 键 词：长叶红砂 RtKCO1 转基因拟南芥 离子稳态 耐盐性 

分 类 号：Q943.2[生物学—植物学]