Seifbarghi Shirin, Borhan M Hossein, Wei Yangdou, Coutu Cathy, Robinson Stephen J, Hegedus Dwayne D
Agriculture and Agri-Food Canada, 107 Science Place, Saskatoon, SK, S7N 0X2, Canada.
Department of Biology, University of Saskatchewan, Saskatoon, Canada.
BMC Genomics. 2017 Mar 29;18(1):266. doi: 10.1186/s12864-017-3642-5.
Sclerotinia sclerotiorum causes stem rot in Brassica napus, which leads to lodging and severe yield losses. Although recent studies have explored significant progress in the characterization of individual S. sclerotiorum pathogenicity factors, a gap exists in profiling gene expression throughout the course of S. sclerotiorum infection on a host plant. In this study, RNA-Seq analysis was performed with focus on the events occurring through the early (1 h) to the middle (48 h) stages of infection.
Transcript analysis revealed the temporal pattern and amplitude of the deployment of genes associated with aspects of pathogenicity or virulence during the course of S. sclerotiorum infection on Brassica napus. These genes were categorized into eight functional groups: hydrolytic enzymes, secondary metabolites, detoxification, signaling, development, secreted effectors, oxalic acid and reactive oxygen species production. The induction patterns of nearly all of these genes agreed with their predicted functions. Principal component analysis delineated gene expression patterns that signified transitions between pathogenic phases, namely host penetration, ramification and necrotic stages, and provided evidence for the occurrence of a brief biotrophic phase soon after host penetration.
The current observations support the notion that S. sclerotiorum deploys an array of factors and complex strategies to facilitate host colonization and mitigate host defenses. This investigation provides a broad overview of the sequential expression of virulence/pathogenicity-associated genes during infection of B. napus by S. sclerotiorum and provides information for further characterization of genes involved in the S. sclerotiorum-host plant interactions.
核盘菌可引起甘蓝型油菜茎腐病，导致倒伏并造成严重产量损失。尽管最近的研究在单个核盘菌致病因子的表征方面取得了重大进展，但在宿主植物上核盘菌感染全过程的基因表达谱分析方面仍存在差距。在本研究中，进行了RNA测序分析，重点关注从感染早期（1小时）到中期（48小时）发生的事件。
转录本分析揭示了核盘菌感染甘蓝型油菜过程中与致病性或毒力相关基因的表达时间模式和幅度。这些基因被分为八个功能组：水解酶、次生代谢产物、解毒、信号传导、发育、分泌效应子、草酸和活性氧产生。几乎所有这些基因的诱导模式都与其预测功能一致。主成分分析描绘了表明致病阶段之间转变的基因表达模式，即宿主穿透、分支和坏死阶段，并为宿主穿透后不久出现短暂的活体营养阶段提供了证据。
目前的观察结果支持核盘菌利用一系列因子和复杂策略来促进宿主定殖并减轻宿主防御的观点。本研究全面概述了核盘菌感染甘蓝型油菜过程中与毒力/致病性相关基因的顺序表达，并为进一步表征参与核盘菌-宿主植物相互作用的基因提供了信息。
