Components of Fusarium elicitor-triggered immunity in Arabidopsis thaliana

了解植物与微生物病原体的相互作用对于控制田间植物病害和改进作物基因型以满足未来粮食安全和可持续生产力的需求至关重要。镰刀菌属是最具侵略性的真菌病原体之一，其感染植物，导致产量损失并产生与人类和牲畜健康相关的真菌毒素。因此，我们开始调查富集镰刀菌属物种的分子，这些分子在植物上具有免疫原性，因为它们在拟南芥中引起典型的早期免疫应答（模式触发免疫，PTI）。这些分子的发现和部分富集使我们能够筛选对这些激发子的免疫应答降低的拟南芥突变体。根据我们的初步数据，我们假设这些突变体是有缺陷的新的核心组成部分的植物免疫镰刀菌物种。这项工作的主要目标是从我们已经确定的两个最有希望的突变体中分离出关键的突变基因。我们通过图位克隆和测序克隆的互补战略，创造了实现这一目标所需的遗传资源。我们将对候选突变基因进行测序和克隆，并使用独立的T-DNA插入系和遗传互补来验证这些基因。我们将进一步证明相应的野生型基因在早期免疫应答和对镰刀菌属物种的抗性中的功能。在其他植物物种中的比较PTI测定和鉴定基因的系统发育分析将进一步显示鉴定的激发子和PTI组分是否在植物免疫中具有潜在的一般功能。

Understanding the interaction of plants with microbial pathogens is pivotal for managing plant diseases in the field and for improvement of crop plant genotypes to meet the future demand of food security and sustainable productivity. Fusarium species are among the most aggressive fungal pathogens that infect plants, cause yield losses and produce mycotoxins of relevance for human and livestock health. We therefore started investigations for enrichment of molecules from Fusarium species, which are immunogenic on plants in the sense that they elicit canonical early immune responses in Arabidopsis thaliana (pattern-triggered immunity, PTI). Finding and partial enrichment of such molecules enabled us to screen for Arabidopsis mutants with reduced immune responses to these elicitors. Based on our preliminary data, we hypothesize that these mutants are defective in novel core components of plant immunity to Fusarium species. The main objective of the proposed work is to isolate the crucial mutated genes from the two most promising mutants we have identified. We have generated the necessary genetic resources to accomplish this by a complementary strategy of map-based cloning and cloning by sequencing. We will perform sequencing and cloning of candidate mutated genes and validate these using independent T-DNA insertion lines and genetic complementation. We will further evidence the function of corresponding wild type genes in early immune responses and in resistance to Fusarium species. Comparative PTI assays in other plant species and phylogenetic analysis of identified genes will further show whether the identified elicitors and PTI components have a potentially general function in plant immunity.