根际促生解淀粉芽胞杆菌SQR9对香蕉根系分泌物响应的转录组分析  

Transcriptomic profiling of plant growth-promoting rhizobacteria Bacillus amyloliquefaciens SQR9 in response to banana root exudates

作　　者：罗兴 冯海超 夏丽明 张瑞福[1] 余光辉[1] 沈其荣[1] 张楠[1] LUO Xing;FENG Haichao;XIA Liming;ZHANG Ruifu;YU Guanghui;SHEN Qirong;ZHANG Nan(Jiangsu Provincial Key Lab of Solid Organic Waste Utilization/Jiangsu Collaborative Innovation Center of Solid Organic Wastes/Educational Ministry Engineering Center of Resource-saving fertilizers,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学江苏省固体有机废弃物资源化研究重点实验室/江苏省有机固体废弃物协同创新中心/教育部资源节约型肥料工程技术研究中心,江苏南京210095

出　　处：《南京农业大学学报》2019年第1期102-110,共9页Journal of Nanjing Agricultural University

基　　金：国家重点研发计划项目(2017YFD0200805;2016YFD0800605);国家自然科学基金青年基金项目(41401321)

摘　　要：[目的]本文旨在阐明根系分泌物介导的植物根际促生细菌(plant growth-promoting rhizobacteria,PGPR)与宿主的互作机制。[方法]利用Illumina高通量测序技术研究促生解淀粉芽胞杆菌SQR9在体外振荡培养条件下对香蕉根系分泌物的转录响应特征,对显著差异表达基因的直系同源基因进行同源蛋白簇(COG)分析。通过Real-time PCR验证部分转录组测序结果,并研究分泌物代表性组分对部分差异基因表达的影响。[结果]香蕉根系分泌物可显著促进菌株SQR9在1/2MSgg培养基中的生长。转录组测序结果表明:根系分泌物处理6 h后菌株SQR9中共有764个基因的表达发生了显著变化,占其基因总数的18.7%,其中上调与下调基因数量分别为485和279。Real-time PCR验证获得的基因表达差异趋势与转录组测序结果一致,证明其结果可信。菌株SQR9中受根系分泌物显著调控的差异基因主要属于碳水化合物转运与代谢、氨基酸转运与代谢、能量产生与转化、转录调控、信号转导和细胞运动等;此外,与促生/生防活性物质合成相关的部分功能基因也被分泌物所诱导。根系分泌物中的葡萄糖、木糖、赤藓糖醇和硬脂酸可诱导SQR9中部分代表性差异基因的表达,但整体的转录组调控现象是分泌物中不同组分共同作用的结果。[结论]香蕉根系分泌物可促进菌株SQR9的生长代谢、信号响应、根际趋化和活性物质合成,这些都有利于SQR9在香蕉根际的存活定殖和促生/生防功能发挥,有助于其与香蕉合作关系的建立。[Objectives] The purpose of this paper is to illustrate the mechanisms involved in root exudates-mediated interactions between hosts and plant growth-promoting rhizobacteria(PGPR).[Methods] The transcriptional profiling of PGPR strain Bacillus amyloliquefaciens SQR9 towards banana root exudates was analyzed by Illumina high-throughput transcriptome sequencing,genes with significantly different expression level in response to root exudates were examined by clusters of orthologous groups of proteins(COG) analysis . Real-time PCR was performed for validating partial of the sequencing results,as well as investigating the effects of the representative components in root exudates on the expression of several significant genes in SQR9.[Results] Banana root exudates significantly stimulate the growth of SQR9 in 1/2 MSgg medium. Transcriptome analysis indicated after treatment with root exudates by 6 h ,764 genes of SQR9 were detected to be significantly regulated,which covered 18.7% of the whole genome of SQR9 and included 485 of up-regulated genes while 279 down-regulated. Real-time PCR validation showed that the expression patterns of the selected genes were in accordance with the results of transcriptional profiling analysis,suggesting that the transcriptome data was reliable. Genes that significantly regulated by root exudates mainly belonged to carbohydrate transport and metabolism,amino acid transport and metabolism, energy production and conversion,transcription,signal transduction mechanisms,and cell motility. Additionally,partial of the genes involved in biosynthesis of functional compounds relating to plant growth-promotion/biocontrol were also activated by root exudates. Glucose,xylose,erythritol,and stearic acid in root exudates could induce the expression of several representative significant genes in SQR9,while the overall regulation in response to root exudates revealed in transcriptomic profiling was the results of interaction among different components in root exudates.[Conclusions] In conclusion,banana

关 键 词：植物根际促生菌 解淀粉芽胞杆菌SQR9 香蕉根系分泌物 转录组 

分 类 号：S144.2[农业科学—肥料学]