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为探讨烟草与黑胫病菌亲和互作在转录水平的分子机制,本研究利用Solexa高通量测序技术分析感病品种红大接菌前0h和接菌后12h、24 h、48 h和72 h茎部组织的基因表达谱.将5个时间点样品的Unigene表达量依次进行两两相比,4个时间点分别鉴定出1 1 434、12 190、5 128、7 428个差异表达基因.GO功能分析表明,已注释的差异表达基因显著富集到细胞组分中的细胞壁、胞外区域和质膜上,分子功能的催化活性、激酶活性、核酸结合转录因子活性和信号转导活性,并主要参与响应刺激、响应胁迫、次级代谢、信号转导等生物学过程.Pathway分析显示,差异表达基因显著富集到多条次生代谢产物生物合成途径和碳水化合物代谢途径,以及与抗病相关的植物与病原菌互作、植物激素信号转导等途径.14类共计36个已知功能差异基因参与植物与病原菌互作Pathway,多数属于PTI途径调控基因,且基因表达量在黑胫病菌侵染中期(48 h)达到最高;仅有4类ETI途径调控基因差异表达,其中抗病负调控因子RIN4在黑胫病侵染前、中期(24 h,48 h)上调表达,信号组分HSP90接菌后24 h下调表达.由此可以推测,受黑胫病菌侵染后,红大品种中PTI途径调控基因能有效响应黑胫病菌胁迫反应,从而提高对黑胫病菌的抵抗能力,而ETI途径调控基因不能有效响应黑胫病菌胁迫反应.本研究初步揭示了烟草黑胫病感病品种在转录水平上的表达差异,为培育优质抗病新品种提供了理论基础.“,”The objective of this study was to investigate the molecular mechanisms of compatible interaction between tobacco and black shank pathogen at the transcriptional level.Solexa sequencing method was used to analyze the gene expression profile of stem tissues of susceptible tobacco Hongda before inoculation and 12 h,24 h,48 h,72 h after inoculation with the pathogen Phytophthora parasitica var.nicotianae.The comparisons of unigene expression of the samples at five time points indicated that 11 434,12 190,5 128,and 7 428 differentially expressed genes from samples at four different time points were identified.Functional analysis of the Gene Ontology revealed that the differentially expressed genes were significantly enriched in cell wall,extracellular region,and plasma membrane.The molecular functions of these genes were involved in catalytic activity,kinase activity,nucleic acid binding transcription factor activity,and signal transduction activity.These genes were mainly participated in the biological processes of response stimulus,response stress,secondary metabolism,signal transduction,and so on.Pathway analysis indicated that differentially expressed genes were significantly involved in multiple processes of secondary metabolite biosynthesis and carbohydrate metabolism,and signal transduction pathways of plant-pathogen interaction,plant hormone,etc.A total of 14 classes including 36 known functional genes were involved in the plant-pathogen interaction pathway.Most of these genes belonged to the PTI pathway,and the highest expression levels of those genes were observed at metaphase (48 h) of infection by P.nicotianae.Only four types of differential expression genes through ETI pathway were observed.Among these genes,the negative regulation factor RIN4 was up-regulated at the early stage (24 h) and metaphase (48 h) of infection infection by P.nicotianae.The signal component HSP90 was down-regulated at 24 h after inoculation.This result indicated that genes related to the regulation of PTI in the susceptible tobacco Hongda can effectively respond to P.nicotianae stress reaction after infection by the pathogen which can improve the resistance of the plant,while the genes related to the regulation of ETI cannot respond to P.nicotianae stress reaction stress reaction.This study revealed the differential expressions of susceptible tobacco cultivar when infected with P.nicotianae transcriptome level,which provides the theoretical basis for breeding of new resistant tobacco cultivar.