Molecular Analysis of Necrotrophic Mycoparasitism in the Predator Yeast Saccharomycopsis schoenii

捕食性酵母 Schoenii 中坏死营养型真菌寄生的分子分析

• 批准号: 448656174
• 负责人: Professor Dr. Jürgen Wendland
• 金额: --
• 依托单位: Institut Mikrobiologie und Biochemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/448656174?language=en
• 关键词: Molecular; Analysis; Necrotrophic; Mycoparasitism; Predator

Our work aims at the molecular analysis of predation in Saccharomycopsis schoenii.Saccharomycopsis species have strong potential because:(i) they can be easily cultivated, are haploid (our unpublished results), are either homothallic or heterothallic and are amenable to forward and reverse genetics.(ii) they show a unique property of necrotrophic mycoparasitism within Saccharomycetales that provides a simple model to study host-pathogen interactions, e.g. in combination with the powerful genetics of S. cerevisiae as a prey organism.(iii) they have a biphasic life-style. They grow saprophytic in full media but switch to a predatory life-style upon starvation. This will allow dissecting virulence genes from metabolic genes.(iv) Saccharomycopsis species may be useful as biocontrol organisms that could be employed in agriculture to reduce the amount of fungicides used to control plant pathogenic fungi. We propose four work packages within this project based on our extensive previous work:(i) The further characterization of the avirulent KSS1 deletion strain in order to answer the following questions:Is there any sensing of prey cells in the kss1 mutant? That is, do predator yeast kss1 cells still grow towards their prey? Are kss1 cells at all able to form penetration pegs? The complementation strain appeared to be better i.e. more virulent than the wildtype strain. Therefore, we will analyze if the expression level of KSS1 influences virulence?(ii) Study the predation process from the predator’s side, particularly by dissecting polarized morphogenesis and the actin cytoskeleton to monitor events that lead to penetration peg formation. We expect actin polarization to the tip of the penetration peg. Yet, of premier interest to us is if there is actin ring formation at the base of the penetration peg and further if there is a requirement of a nuclear division during penetration peg formation and the entry of a nucleus in the penetration peg. (iii) Characterization of the predation process from the viewpoint of the prey cell. This shall answer the key question whether (or for how long) the plasma membrane of the S. cerevisiae prey cells stays intact during predation. Here we will also analyse subcellular changes in prey cell compartments, e.g. the vacuole and the mitochondria using fluorescence microscopy.(iv) Analysis of additional components of the MAPK-signaling cascade in S. schoenii, particularly the MAP kinase FUS3 and the downstream transcription factor STE12. This shall answer the key question if and how predator yeasts prioritize between predation and mating.

本研究的目的是对Schoenii拟复膜菌的捕食行为进行分子分析。拟复膜菌具有很强的潜力，因为：（1）它们容易培养，是单倍体（我们未发表的结果），是同宗配合或异宗配合，并且适合正向和反向遗传。(ii)它们显示出在链霉菌目内的坏死营养型真菌寄生的独特性质，其提供了研究宿主-病原体相互作用的简单模型，例如与S.酿酒酵母作为猎物生物。(iii)他们的生活方式是双向的它们在全介质中生长，但在饥饿时转变为掠夺性的生活方式。这将允许从代谢基因中分离毒力基因。(iv)拟青霉属物种可用作生物防治生物，其可用于农业以减少用于防治植物病原真菌的杀真菌剂的量。我们提出了四个工作包在这个项目的基础上，我们广泛的以前的工作：（一）无毒KSS 1缺失菌株的进一步表征，以回答以下问题：是否有任何感测的猎物细胞中的KSS 1突变体？也就是说，捕食者酵母kss 1细胞仍然朝着猎物生长吗？kss 1细胞是否能够形成穿透钉？互补菌株似乎比野生型菌株更好，即毒性更强。因此，我们将分析KSS 1的表达水平是否影响毒力？(ii)从捕食者的角度研究捕食过程，特别是通过解剖极化形态发生和肌动蛋白细胞骨架来监测导致穿透钉形成的事件。我们预计肌动蛋白极化到穿透钉的尖端。然而，我们最感兴趣的是，如果有肌动蛋白环形成的基础上的渗透钉，并进一步如果有一个核分裂过程中的渗透钉形成和核的进入渗透钉的要求。(iii)从被捕食细胞的观点描述捕食过程。这将回答关键问题是否（或多久）的质膜S。酿酒酵母被捕食细胞在捕食过程中保持完整。在这里，我们也将分析亚细胞的变化，猎物细胞隔间，例如，液泡和线粒体使用荧光显微镜。(iv)对S. schoenii，特别是MAP激酶FUS 3和下游转录因子STE 12。这将回答关键的问题，如果以及如何捕食酵母优先捕食和交配。