Exploring and Exploiting Epigenetic Plant Immunity

探索和利用表观遗传植物免疫

基本信息

批准号：
BB/W015250/1
负责人：
Jurriaan Ton
金额：
$ 97.3万
依托单位：
University of Sheffield
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2023
资助国家：
英国
起止时间：
2023 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FW015250%2F1
关键词：
Exploring Exploiting Epigenetic Plant Immunity

项目摘要

Crop protection is of crucial importance to the global food supply chain. Despite the major technological advances since the green revolution, plant diseases continue to pose a threat to food security. Aggravated by legislative restrictions on the use of pesticides and GM crops, there is an urgent need to develop alternative crop protection methods. This objective has become a key priority of the sustainable intensification agenda in the UK. Quantitative disease resistance is an attractive concept for crop protection. Unlike qualitative resistance, which relies on single resistance genes, quantitative resistance depends on a multitude of interacting genes and mechanisms. Accordingly, it is more resilient against co-evolution by pathogens and offers broad-spectrum protection against multiple pathogen isolates and species. Despite these advantages, however, quantitative resistance has not been exploited to its full potential, because of its complex regulation and sometimes variable effectiveness compared to conventional protection strategies. For instance, while quantitative resistance slows down disease progression, it is often too weak to prevent infection by virulent pathogens completely.Induced resistance (IR) is an adaptive immune response that allows plants to boost their innate level of quantitative resistance. IR typically develops after recovery from biotic stress and is based on a form of immune memory called priming, which enables a faster and/or stronger defence induction against future pathogen attack. We have previously shown that long-lasting IR in the model plant Arabidopsis has an epigenetic basis, involving genome-wide reductions in DNA methylation, which can be transmitted to subsequent generations. While epigenetic IR (epi-IR) after exposure to disease stress can be variable, we found that direct manipulation of the Arabidopsis epigenome can yield near complete levels of protection against downy mildew disease. The epigenetic loci controlling this artificial epi-IR response are stable over multiple generations and are not associated with major reductions in plant growth, making it attractive for exploitation in crop protection. However, crops have larger genomes than Arabidopsis, rendering them more vulnerable to genome-wide reductions in DNA methylation. Thus, to advance this research, we propose to develop a more precise and adjustable method to introduce epigenetic variation in plant genomes. This would not only be of high translational value to crop protection and breeding, but also represent a valuable research tool to explore the complex mechanisms by which epigenetically altered DNA loci prime defence genes.Based on preliminary proof-of-concept results, our project will develop a novel tool for adjustable introduction of epigenetic variation in plant genomes, taking advantage of the expertise and resources in our labs. This adjustable epi-mutagenesis will be optimised for epi-IR against downy mildew disease in both Arabidopsis and lettuce. We will then use the method to screen Arabidopsis mutants impaired in epigenetic gene regulation for their ability to develop and retain epi-IR, followed by next-generation sequencing analyses to reveal the underpinning mechanisms on a genome-wide scale. In parallel, we will exploit our method by selecting for epigenetically modified lettuce lines with high levels of epi-IR against downy mildew disease. These lines will be characterised for commercially relevant traits and used to generate epigenetic recombinant inbred lines, in order to separate epi-IR from potentially undesirable effects on growth and seed set. The project will be conducted in partnership with ENZA, a global crop breeding company covering >50% of the lettuce seed market in the UK. This partnership will be supervised by a business development manager to ensure efficient knowledge exchange, manage intellectual property, and facilitate adoption of the technology by the industry partner.

作物保护对全球食品供应链至关重要。尽管自绿色革命以来技术取得了重大进步，但植物病害仍然对粮食安全构成威胁。由于对农药和转基因作物使用的立法限制加剧，迫切需要开发替代作物保护方法。这一目标已成为英国可持续集约化议程的一个关键优先事项。定量抗病性对于作物保护来说是一个有吸引力的概念。与依赖于单一抗性基因的定性抗性不同，定量抗性取决于多种相互作用的基因和机制。因此，它对病原体的共同进化更具弹性，并针对多种病原体分离株和物种提供广谱保护。然而，尽管有这些优势，定量抗性尚未充分发挥其潜力，因为与传统的保护策略相比，其调节复杂且有时效果可变。例如，虽然定量抗性可以减缓疾病进展，但它通常太弱，无法完全防止有毒病原体的感染。诱导抗性（IR）是一种适应性免疫反应，可以使植物提高其先天的定量抗性水平。 IR通常在从生物应激中恢复后发生，并且基于一种称为启动的免疫记忆形式，它能够更快和/或更强大地诱导防御未来病原体的攻击。我们之前已经证明，模式植物拟南芥中的持久IR具有表观遗传基础，涉及全基因组DNA甲基化的减少，这种减少可以遗传给后代。虽然暴露于疾病胁迫后的表观遗传 IR (epi-IR) 可能会发生变化，但我们发现直接操纵拟南芥表观基因组可以产生接近完全水平的针对霜霉病的保护。控制这种人工表观红外反应的表观遗传位点在多代中保持稳定，并且与植物生长的大幅减少无关，这使得它在作物保护中具有吸引力。然而，农作物的基因组比拟南芥更大，这使得它们更容易受到全基因组 DNA 甲基化减少的影响。因此，为了推进这项研究，我们建议开发一种更精确和可调整的方法来在植物基因组中引入表观遗传变异。这不仅对作物保护和育种具有很高的转化价值，而且也是探索表观遗传改变 DNA 位点主要防御基因的复杂机制的一个有价值的研究工具。根据初步的概念验证结果，我们的项目将利用我们实验室的专业知识和资源，开发一种新工具，用于在植物基因组中可调整地引入表观遗传变异。这种可调节的表观诱变将针对拟南芥和生菜中针对霜霉病的表观红外进行优化。然后，我们将使用该方法筛选表观遗传基因调控受损的拟南芥突变体，以确定其发展和保留 Epi-IR 的能力，然后进行下一代测序分析，以揭示全基因组范围内的基础机制。与此同时，我们将通过选择具有高水平的表观红外抗霜霉病的表观遗传修饰生菜品系来利用我们的方法。这些品系将具有商业相关性状，并用于产生表观遗传重组自交系，以便将 Epi-IR 与对生长和结籽的潜在不良影响分开。该项目将与 ENZA 合作开展，ENZA 是一家全球作物育种公司，覆盖英国 50% 以上的生菜种子市场。这种合作伙伴关系将由业务开发经理监督，以确保有效的知识交流、管理知识产权并促进行业合作伙伴采用该技术。