木薯铵转运蛋白基因MeAMT1.5的克隆及功能初步分析  

Cloning and Functional Analysis of Ammonium Transporter Gene Me AMT1.5from Manihot esculenta

作　　者：刘银弟 朱云峰 夏幽泉[1] 夏金泽 陈秀珍 江行玉[1] 周扬[2] Liu Yindi;Zhu Yunfeng;Xia Youquan;Xia Jinze;Chen Xiuzhen;Jiang Xingyu;Zhou Yang(Hainan Key Laboratory for Biotechnology of Salt Tolerant Crops,School of Tropical Crops,Hainan University,Haikou,570228;Key Laboratory for Quality Regulation of Tropical Horticultural Crops of Hainan Province,School of Horticulture,Hainan University,Haikou,570228)

机构地区：[1]海南大学热带作物学院,海南省耐盐作物生物技术重点实验室,海口570228 [2]海南大学园艺学院海南省热带园艺作物品质调控重点实验室,海口570228

出　　处：《分子植物育种》2021年第24期8048-8054,共7页Molecular Plant Breeding

基　　金：海南省基础与应用基础研究计划(自然科学领域)高层次人才项目(2019RC046);国家自然科学基金项目(31660253);国家重点研发计划项目(2018YFD1000500)。

摘　　要：铵态氮是植物吸收的主要无机氮源,铵转运蛋白(ammonium transporter,AMT)在其吸收过程中发挥着重要作用。本研究从木薯基因组数据库中进行BLAST搜索获得一个铵转运蛋白基因Me AMT1.5,运用生物信息学技术对其理化性质进行分析,并利用酵母异源表达系统对其功能进行初步研究。结果表明,Me AMT1.5基因编码468个氨基酸,分子式为C_(2348)H_(3502)N_(576)O_(635)S_(14),分子量为50.41 k D,理论等电点为5.32,不稳定指数为28.24,属于稳定蛋白。该蛋白含有11个跨膜区,蛋白质二级结构包含有四种构象,以α-螺旋和无规则卷曲为主。与其他植物的进化关系分析表明Me AMT1.5与巴西橡胶树Hb AMT1.5亲缘关系最近。酵母功能互补试验显示转Me AMT1.5基因酵母在低氮条件下生长好于对照,表明其是一个高亲和性铵转运蛋白。通过对Me AMT1.5的功能初步研究有助于下一步深入研究木薯氮高效利用的机理。Ammonium nitrogen is the main source of inorganic nitrogen uptake by plants.Ammonium transporter(AMT)plays an important role in its absorption.In this study,an ammonium transporter gene,MeAMT1.5,was obtained from the cassava genome database by BLAST search.Bioinformatics was used to analyze the physicochemical properties of MeAMT1.5,and its function was studied using yeast heterologous expressing system.The results showed that MeAMT1.5 gene encoded 468 amino acids,with a molecular formula of C_(2348)H_(3502)N_(576)O_(635)S_(14),a molecular weight of 50.41 k D and a theoretical isoelectric point of 5.32.The instability index of Me AMT1.5 was28.24,indicating that it is a stable protein.The protein contains 11 transmembrane domains.The secondary structure of MeAMT1.5 protein contained four conformations,and mainly comprised alpha helix and random coil.Phylogenetic analysis showed that the MeAMT1.5 protein was closely related to Hevea brasiliensis HbAMT1.5.The yeast functional complementary test showed that yeast transformed with MeAMT1.5 grew better than untransformed yeast strain under low nitrogen condition,indicating that it was a high affinity ammonium transporter.The preliminary study on the function of MeAMT1.5 is helpful to further study the mechanism of efficient nitrogen utilization of cassava.

关 键 词：木薯(Manihot esculenta Crantz) 铵转运蛋白 生物信息学分析 MeAMT1.5 

分 类 号：S533[农业科学—作物学]