烟草NtNRAMP3.1 基因克隆、表达及Cd转运特性分析  

Cloning,expression and Cd transport characteristic analysis of NtNRAMP3.1 gene from Nicotiana tabacum

作　　者：陈邦兰 龙涛 高永峰[1] 黄仁华[1,2] 刘继恺[1,2,3] CHEN Bang-lan;LONG Tao;GAO Yong-feng;HUANG Ren-hua;LIU Ji-kai(College of Life Science and Engineering,Southwest University of Science and Technology,Mianyang,Sichuan 621010,China;Nation­al Key Laboratory of Nuclear Waste and Environmental Safety,Southwest University of Science and Technology,Mianyang,Sichuan 621010,China;National Collaborative Innovation Center for Nuclear Waste and Environmental Safety,Southwest University of Science and Tech­nology,Mianyang,Sichuan 621010,China)

机构地区：[1]西南科技大学生命科学与工程学院,四川绵阳621010 [2]西南科技大学核废物与环境安全国防重点实验室,四川绵阳621010 [3]核废物与环境安全省部共建协同创新中心,四川绵阳621010

出　　处：《西南农业学报》2022年第2期438-445,共8页Southwest China Journal of Agricultural Sciences

基　　金：国家自然科学基金项目(31500205);四川省科技计划重点研发项目(2020YFS0344);西南科技大学大学生创新创业训练项目(S201910619065)。

摘　　要：【目的】探究烟草(Nicotiana tabacum L.)自然抗性相关巨噬细胞蛋白(Natural resistance associated macrophage proteins,NRAMPs)在金属跨膜转运所起的作用。【方法】克隆NtNRAMP3.1基因,并对其序列和表达模式进行分析,同时通过酵母异源表达对其编码蛋白的Cd转运特性进行研究。【结果】烟草NtNRAMP3.1基因全长1542 bp,编码513个氨基酸残基的蛋白质。氨基酸序列比对和进化树分析发现,NtNRAMP3.1具有11个跨膜结构域,含有NRAMP家族特有的CTM结构域,与拟南芥AtNRAMP3和AtNRAMP4的亲缘关系最近,属于NRAMP家族的第一亚组。表达模式分析表明,NtNRAMP3.1在叶中的表达量高于根,但是其对不同重金属胁迫表现出不同的应答模式。酵母实验发现,异源表达NtNRAMP3.1基因显著提高了酵母细胞中Cd的积累量,增加了酵母对Cd的敏感性。【结论】NtNRAMP3.1基因的表达具有组织特异性,且受到多种重金属胁迫的调控,其编码的蛋白是Cd向内流入的转运蛋白。本研究结果为进一步分析NtNRAMP3.1基因在植物金属离子吸收转运中的功能提供了一定的理论依据。[Obective]In order to explore the function of NRAMP genes in metal transmembrane transport from Nicotiana tabacum L.,the Nt-NRAMP3.1 gene was cloned and the phylogenetic features and sequence characteristics of its encoding protein were analyzed.[Method]The NtNRAMP3.1 gene was cloned,and its sequence and expression patterns were analyzed,and the Cd transport properties of its encoded protein were studied by heterologous expression in yeast.[Result]The full length of NtNRAMP3.1 gene was 1542 bp,and encoded a protein of 513 amino acid residues.Multiple sequence alignment and phylogenetic relationship analysis showed that NtNRAMP3.1 belonged to the subfamily I of NRAMP family,and contained 11 transmembrane domains(TMs)and a conserved consensus transport motif(CTM).Two NRAMPs from Arabidopsis,AtNRAMP3 and AtNRAMP4 showed the closest phylogenetic relationship with NtNRAMP3.1.Besides,expression profile analysis indicated that NtNRAMP3.1 had higher expression level in tobacco leaves than in roots,but exhibited various responses under different heavy metal stresses.Moreover,heterologous expression of NtNRAMP3.1 enhanced the Cd-induced sensitivity of yeast which may be due to the increased cell accumulation of Cd.[Conclusion]NtNRAMP3.1 is the homologous gene of NRAMP in tobacco,and encodes a transporter involved in Cd influx.The expression of NtNRAMP3.1 was transcriptionally regulated by different heavy metal stresses in a tissue specific manner.The results of this study might provide a theoretical foundation for further investigation of the biological function of NtNRAMP3.1 in plant metal iron uptake and translocation.

关 键 词：烟草 NRAMP 基因表达 Cd转运 酵母 

分 类 号：S572[农业科学—烟草工业]