Functional genomics of Pseudozyma flocculosa, a biocontrol agent of powdery mildews

白粉病生物防治剂絮状假酵母的功能基因组学

• 批准号: RGPIN-2016-05235
• 负责人: Bélanger, Richard
• 金额: $ 3.72万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=645022
• 关键词: Functional; genomics; Pseudozyma; flocculosa; biocontrol

Practical application of biological control of plant pathogens presupposes a thorough understanding of the genetic, molecular and ecological events underlying such phenomena. This challenge has been the focal point of the research activities carried out in the applicant's laboratory over the last 25 years. In the previous installment, we have made some major strides toward elucidating the complex factors governing the biocontrol properties of Pseudozyma flocculosa, a natural antagonist of powdery mildew fungi. Of particular significance, we reported the following: 1) the discovery of genes and a gene cluster involved in flocculosin biosynthesis and establishment of an unsuspected close link with the phylogenetically related plant pathogen model fungus Ustilago maydis; 2) the association of specific enzymatic activities distinguishing the glycolipid structures produced by P. flocculosa and U. maydis; 3) the complete sequencing and genomic annotation of P. flocculosa, the first such report for a biocontrol agent; and 4) the comparative analysis of P. flocculosa genome with that of related Ustilaginales, U. maydis, Sporisorium reilianum and U. hordei, aimed at identifying the genetic factors that confer specific lifestyles in fungi. This latter achievement is perceived as a major breakthrough since it opens new opportunities to understand the subtle factors that make phylogenetically related fungi adopt opposite lifestyles. In the context of this application and in direct link with our recent progress, the objectives are: 1) to carry out the first full transcriptomic analysis of a tritrophic interaction BCA-fungal pathogen-plant using the system P. flocculosa-Blumeria graminis-barley; 2) with a specific emphasis on the unique factors discovered in the genome of P. flocculosa, to identify the determinant(s) that confer P. flocculosa, its biocontrol activity on powdery mildew fungi; 3) to identify the functional virulence factors of powdery mildew fungi by deductive analysis of their repression under P. flocculosa attack; 4) to understand the plant's role in sustaining the BCA-plant pathogen interaction; and 5) to conduct functional analyses of biocontrol determinants (genes) through reverse genetics in P. flocculosa and/or complementation in U. maydis. Fulfillment of these objectives will generate novel and distinctive information with regards to: the genetic determinants that regulate the biocontrol activity of P. flocculosa and those that regulate the pathogenicity of powdery mildew fungi against plants, and how expression (or repression) of these determinants influence the ecology of fungi. These results will have far reaching impact into the field of plant pathology as our model will provide unique data into the intrinsic genetic factors that separate and modulate two phylogenetically related fungi to behave as biocontrol agent or plant pathogen.**

对植物病原体的生物控制的实际应用前提是对这种现象的遗传，分子和生态事件的彻底理解。在过去25年中，这一挑战一直是申请人实验室中进行的研究活动的重点。在上一期中，我们朝着阐明了pseudozyma flocculosa的生物防治特性的复杂因素方面取得了一些重大进步，这是白粉病真菌的天然拮抗剂。我们报道了以下几点：1）发现基因的发现和与絮凝素生物合成的基因簇，并建立了与系统发育相关的植物病原体模型真菌ustilago Maydis的无关紧要的密切联系； 2）特定酶促活性的关联，以区分絮状疟原虫和梅迪斯产生的糖脂结构； 3）P. thlocculosa的完整测序和基因组注释，这是生物防治剂的第一份报告； 4）对絮状假单胞菌基因组的比较分析与相关的尿道菌，美国Maydis，孢子虫珍珠氏菌和U. Hordei的比较分析，旨在识别赋予真菌中特定生活方式的遗传因素。后一个成就被认为是一个主要的突破，因为它为理解使系统发育相关的真菌采用相反生活方式的微妙因素打开了新的机会。在此应用程序的背景下，并与我们最近的进度直接联系，目的是：1）使用系统P. grocculosa blumeria graminis-barley对粮食相互作用进行首次完整的转录组分析BCA - 芬科病原体植入； 2）特别强调了在絮状疟原虫基因组中发现的独特因素，以识别赋予絮状假单胞菌的决定因素，该决定因素是其对白粉病真菌的生物控制活性； 3）通过对絮状斑块发作下的抑制作用分析白粉病真菌的功能性毒力因子； 4）了解植物在维持BCA植物病原体相互作用方面的作用； 5）通过在美国Maydis中的絮凝杆菌和/或补体中的反向遗传学进行生物学决定因素（基因）的功能分析。实现这些目标将对以下方面产生新颖和独特的信息：调节絮状疟原虫生物防治活性的遗传决定因素，以及调节白粉病真菌对植物的致病性的遗传决定因素，以及这些决定性对植物的表达（或抑制）如何影响Fungi的生态学。 这些结果将对植物病理的领域产生巨大影响，因为我们的模型将为内在的遗传因子提供独特的数据，这些遗传因素将两种系统发育相关的真菌分开，以作为生物防治剂或植物病原体作用。**********************