盐芥ThPHT1;8基因的克隆和功能分析  

Cloning and Function Analysis of ThPHT1;8 Gene in Thellungiella Salsuginea

作　　者：杨少辉[1] 李爽[1] 寇莹莹[1] 王洁华[1] 宋英今[1] 关春峰[1] Yang Shaohui;Li Shuang;Kou Yingying;Wang Jiehua;Song Yingjin;Guan Chunfeng(School of Environmental Science and Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学环境科学与工程学院,天津300350

出　　处：《天津大学学报（自然科学与工程技术版）》2018年第4期380-388,共9页Journal of Tianjin University：Science and Technology

基　　金：转基因生物新品种培育重大专项(2014ZX0800404B);天津市应用基础与前沿技术研究计划资助项目(15JCQNJC14700)~~

摘　　要：磷(P)是植物生长发育过程中重要的矿质营养元素之一,PHT1磷酸转运蛋白家族负责调控植物从土壤中吸收磷以及细胞间无机磷(Pi)的转运.本文以盐芥幼苗根cDNA为材料,克隆到盐芥磷酸转运蛋白ThPHT1;8基因.生物信息学分析结果表明,ThPHT1;8蛋白编码525个氨基酸残基,蛋白分子质量为58.1,ku,等电点6.33,是一个定位在细胞膜上的疏水、无信号肽的非分泌性蛋白,含有高亲和力磷酸转运蛋白典型的跨膜结构.实时定量PCR结果显示,低磷胁迫能促进ThPHT1;8基因在盐芥根部的表达,而且不同磷浓度处理下ThPHT1;8基因表达的模式不同.ThPHT1;8基因在转基因拟南芥中的生物学功能研究表明,不同浓度低磷胁迫处理下,与野生型拟南芥相比,35S:ThPHT1;8转基因拟南芥幼苗的主根根长显著增加、侧根密度显著降低,叶绿素含量、无机磷和总磷含量提高,花青素含量降低.上述结果表明,盐芥ThPHT1;8基因确实参与低磷胁迫时植物的应答,能够提高转基因拟南芥的耐低磷能力,为土壤磷高效利用提供了一种有潜力的候选功能基因.Phosphorus(P)is one of the most limiting mineral nutrients for plant growth and development.In plants,the uptake from soil and intercellular transport of inorganic phosphate(Pi)are mediated by the PHT1 family.In this work,we obtained the ThPHT1;8 gene through cloning from cDNA of Thellungiella salsuginea seedings roots.Bioinformatics analysis indicated that ThPHT1;8 protein had 525 amino acid residues.The molecular weight of the protein was 58.1 ku and the isoelectric point was 6.33.It was a hydrophobic and non-secreted protein with no signal peptide.ThPHT1;8 possessed the major characteristics of high-affinity phosphate transporters,such as transmembrane structure.Real-time quantitative PCR showed that the expression of ThPHT1;8 was strongly enhanced by low phosphorus stress in roots of Thellungiella salsuginea and the patterns of expression were different under different phosphorus stresses.The biological function of ThPHT1;8 gene indicated that 35S:ThPHT1;8 transgenic Arabidopsis had longer primary roots and less lateral root density than wild-type Arabidopsis under deficient phosphorus conditions.The contents of inorganic phosphorus,total phosphorus and chlorophyll increased in the 35S:ThPHT1;8 transgenic Arabidopsis,but the content of anthocyanin decreased.To conclude,ThPHT1;8 could enhance the tolerance of plants to low environmental phosphorus and improve transgenic Arabidopsis resistance to low phosphorus capacity.The study offers a functional candidate gene for efficient utilization of soil phosphorus.

关 键 词：盐芥 磷酸转运蛋白 生物信息学 ThPHT1 8基因 

分 类 号：Q785[生物学—分子生物学]