SeptPROTECT: Rapid effector discovery to protect wheat from Septoria tritici blotch disease

SeptPROTECT：快速发现保护小麦免受小麦壳针孢斑枯病的效应子

• 批准号: BB/X016552/1
• 负责人: Graeme Kettles
• 金额: $ 65.9万
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FX016552%2F1
• 关键词: SeptPROTECT; Rapid; effector; discovery; protect

Plants are under continual attack from pathogens in their environment. This is a huge problem in agriculture, where plant health and productivity are crucial for ensuring the food supply.Plants protect themselves from disease with an immune system that detects and blocks invading microbes. However, microbial pathogens are continually evolving to suppress this immune system. One set of tools that pathogens use to evade the plant immune system are small, secreted proteins known as effectors. Plants can regain the upper hand by evolving disease resistance genes that detect pathogen effectors and initiate activation of immune responses.Zymoseptoria tritici is a fungus that causes Septoria tritici blotch disease of wheat plants, a major problem for farmers in the UK. Currently farmers rely on plant resistance genes that serve to recognise the fungus and limit disease development on the leaf. This fungus, however, evolves rapidly and escapes from the recognition and control provided by plant resistance genes. While we currently do not know how the fungus evades plant resistance genes, we hypothesise that the mutation or deletion of fungal effectors is one key way in which this pathogen evades recognition. A critical knowledge gap is that we do not know the identity of the effectors that are recognised by plant resistance proteins. Therefore, it is currently impossible for us to know or predict which changes in the pathogen are a threat to wheat.Identification of Z. tritici effectors has previously been challenging as this fungus is highly diverse, and there are many differences in DNA sequences between different strains. We have developed a simple but powerful method for the identification of fungal effectors recognised by corresponding wheat resistance genes. Here we will apply this new method to identify the fungal effectors recognised by four different resistance genes currently used in commercial UK wheat breeding programmes.The second goal of the project is to identify specific changes that occur in these effectors that enable them to escape recognition by wheat resistance genes. To do this, we will examine the sequence diversity found in fungal effector genes in hundreds of different strains collected directly from UK wheat fields. We will combine this sequence diversity information with knowledge of which strains are able to cause disease on wheat varieties carrying specific resistance genes. Together, this information will enable us to test and conclude which evolutionary changes in the effector genes allow the fungus to "gain virulence" on particular wheat varieties.The final goal of the project is to develop a system whereby information on the presence and frequency of Z. tritici strains able to overcome specific disease resistance genes can rapidly be made publicly available. We will do this by implementing a system similar to that developed for tracking evolution of the SARS-CoV-2 virus during the COVID pandemic. Similar tracking systems exists for other plant pathogens, but not for Z. tritici despite its agronomic importance. In the future, this system may allow us to accurately track the gain of virulence mutations in the fungal population across a large geographical area. The benefit of this is that specific wheat varieties could then be chosen to be grown in certain areas, as they were predicted to be most resistant against the local pathogen population.

植物不断受到环境中病原体的侵袭。这是农业中的一个大问题，植物的健康和生产力对确保粮食供应至关重要。植物通过检测和阻止入侵微生物的免疫系统保护自己免受疾病的侵害。然而，微生物病原体不断进化以抑制这种免疫系统。病原体用来逃避植物免疫系统的一套工具是被称为效应子的小的分泌蛋白。植物可以通过进化抗病基因来重新获得优势，这些抗病基因可以检测病原体效应物并启动免疫反应的激活。Zymoseptoria triacetylum是一种真菌，会导致小麦植株的Septoria triacetylblotch病，这是英国农民的一个主要问题。目前，农民依靠植物抗性基因来识别真菌并限制叶片上的疾病发展。然而，这种真菌进化迅速，并逃脱了植物抗性基因的识别和控制。虽然我们目前还不知道真菌是如何逃避植物抗性基因的，但我们假设真菌效应子的突变或缺失是这种病原体逃避识别的一种关键方式。一个关键的知识差距是，我们不知道植物抗性蛋白识别的效应子的身份。因此，我们目前无法知道或预测病原菌的哪些变化对小麦是一种威胁。由于这种真菌是高度多样性的，并且不同菌株之间的DNA序列存在许多差异，因此trilactin效应子以前一直具有挑战性。我们已经开发了一种简单而强大的方法来鉴定相应的小麦抗性基因所识别的真菌效应子。在这里，我们将应用这种新方法来识别目前在英国商业小麦育种计划中使用的四种不同抗性基因所识别的真菌效应子。该项目的第二个目标是识别这些效应子中发生的特定变化，这些变化使它们能够逃脱小麦抗性基因的识别。为此，我们将研究直接从英国麦田收集的数百种不同菌株中真菌效应基因的序列多样性。我们将联合收割机结合这些序列多样性信息，了解哪些菌株能够在携带特定抗性基因的小麦品种上引起疾病。总之，这些信息将使我们能够测试和得出结论，在效应基因的进化变化，使真菌“获得毒性”的特定小麦品种。能够克服特定疾病抗性基因的抗病菌株可以迅速公开获得。为此，我们将实施一个类似于COVID大流行期间为追踪SARS-CoV-2病毒演变而开发的系统。类似的跟踪系统存在于其他植物病原体中，但不适用于Z。尽管它在农业上很重要。在未来，这个系统可能使我们能够准确地跟踪真菌种群中的毒力突变在大的地理区域内的增益。这样做的好处是，可以选择特定的小麦品种在某些地区种植，因为预计它们对当地病原体种群的抵抗力最强。