Identification of CsLOB1 target genes that promote citrus canker disease

鉴定促进柑橘溃疡病的 CsLOB1 靶基因

• 批准号: 326067585
• 负责人: Professor Dr. Thomas Lahaye
• 金额: --
• 依托单位: Abteilung für Allgemeine Genetik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/326067585?language=en
• 关键词: Identification; CsLOB1; target; genes; promote

PthA4, a transcription activator-like effector (TALE) from the citrus canker pathogen Xanthomonas citri pv. citri (Xcc), promotes disease via transcriptional activation of the citrus CsLOB1 gene that encodes a lateral organ boundary (LBD) protein. Since LBD proteins are transcription factors its conceivable that not CsLOB1 itself but rather target genes of CsLOB1, herein designated as dtCsLOB1 genes (direct targets of CsLOB1), will induce physiological changes in host cells that promote bacterial disease. We aim to identify dtCsLOB1 genes and intend to clarify how their expression translates into physiological changes that promote bacterial disease. CsLOB1 target promoters will be identified by a combination of transcriptome profiling (RNA-Seq) and chromatin immunoprecipitation (ChIP-Seq). The possible disease contribution of identified dtCsLOB1 genes will be studied by functional complementation of disease-compromised Xcc pthA4 mutant strains (incapable of activating CsLOB1) with dTALEs that specifically induce expression of individual dtCsLOB1 genes. While Xcc effectors act inside host cells, the pathogen multiplies in the apoplast, which implies that TALE-induced CsLOB1 expression should cause changes in apoplastic fluids. Accordingly, we will also study the impact of CsLOB1 expression on the composition of apoplastic fluids from citrus leaves via mass-spectrometry-based metabolite/proteome profiling to identify changes that affect Xcc growth. Metabolite/proteome-profiling in conjunction with the gene/transcript-based approaches should provide indications of how expression of dtCsLOB1 genes translates into physiological responses that promote apoplastic growth of Xcc. We envision that our studies have the potential to uncover novel microbial invasion strategies that are possibly conserved across phylogenetically diverse pathogenic and/or symbiotic plant-associated microbes.

PthA 4是柑橘溃疡病病原体柑橘黄单胞菌致病变种（Xanthomonascitripv.）柑橘（Xcc）通过转录激活编码侧向器官边界（LBD）蛋白的柑橘CsLOB 1基因来促进疾病。由于LBD蛋白是转录因子，因此可以想象不是CsLOB 1本身而是CsLOB 1的靶基因，在本文中称为dtCsLOB 1基因（CsLOB 1的直接靶），将诱导宿主细胞中促进细菌疾病的生理变化。我们的目标是确定dtCsLOB 1基因，并打算澄清它们的表达如何转化为促进细菌疾病的生理变化。将通过转录组分析（RNA-Seq）和染色质免疫沉淀（ChIP-Seq）的组合鉴定CsLOB 1靶启动子。将通过疾病受损Xcc pthA 4突变株（不能激活CsLOB 1）与特异性诱导单个dtCsLOB 1基因表达的dTALE的功能互补，研究已鉴定dtCsLOB 1基因的可能疾病贡献。虽然Xcc效应物在宿主细胞内起作用，但病原体在质外体中繁殖，这意味着TALE诱导的CsLOB 1表达应引起质外体流体的变化。因此，我们还将通过基于质谱的代谢物/蛋白质组分析研究CsLOB 1表达对柑橘叶片质外体液组成的影响，以确定影响XCC生长的变化。代谢物/蛋白质组分析结合基因/转录本为基础的方法应该提供的指示如何表达的dtCsLOB 1基因转化为生理反应，促进XCC的质外体生长。我们设想，我们的研究有可能发现新的微生物入侵策略，这些策略可能在遗传多样性的病原性和/或共生植物相关微生物中保守。