Deciphering plant stress memory: the exploration of how DNA methylation and the rhizosphere microbiome control stress memory in plants

解读植物逆境记忆：探索DNA甲基化和根际微生物如何控制植物逆境记忆

• 批准号: BB/Z514810/1
• 负责人: Samuel Wilkinson
• 金额: $ 52.71万
• 依托单位: University of York
• 依托单位国家: 英国
• 项目类别: Fellowship
• 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%2FZ514810%2F1
• 关键词: Deciphering; plant; stress; memory; exploration

Plant pests and pathogens pose a major threat to the global food supply. Pesticides are currently the primary control strategy however there is clear evidence that they can negatively impact the health of humans and the wider environment. To ensure a sustainable future for our food supply, agriculture must abandon its reliance on harmful chemical pesticides. Enhancing the plant's natural ability to resist pests such as caterpillars will help achieve this goal. In this fellowship I will decipher the mechanisms underpinning one aspect of the plants immune system which has great potential for exploitation. Following exposure to specific environmental stimuli such as mild pest damage, plants become more resistant to future attack. This phenomenon is known as acquired or induced resistance and is type of stress memory. The formation of stress memory involves changes in a plant's epigenome, the collection of chemical modifications which regulate the plants genome. In a recent publication I identified that a reduction in one specific modification, DNA methylation, at specific genomic regions is essential for long-lasting stress memory and resistance against chewing herbivores. The removal of DNA methylation, DNA demethylation, has also been shown to influence the plant root associated microbiome by controlling the production of root exudates and in turn the recruitment of beneficial microbes. These recent findings raise a major unanswered question, is stress memory in plants underpinned by the combination of DNA methylation and microbiomes? More specifically, does stress induced loss of DNA methylation regulate the recruitment of a beneficial microbiome to plant roots and does this facilitate stress memory and long-lasting resistance? In this fellowship I will investigate these timely questions and generate transformative new insights about the mechanisms of plant stress adaptation. The research programme for the fellowship will be split into four objectives addressed using the important crop species tomato (Solanum lycopersicum; Objectives 1-3) and the model plant Arabidopsis thaliana (Objective 4). Objective 1, investigate the requirement of a functional soil microbiome for plants to express long-lasting induced resistance after herbivory stress or removal of DNA methylation using an inducible DNA demethylation system. Objective 2, characterise the herbivory stress induced shift in the root transcriptome associated with stress memory and determine whether this results in a long-lasting change in root exudation and recruitment of a beneficial microbiome. Objective 3, demonstrate that herbivory stress induces a loss of DNA methylation and establish if this regulates root exudate metabolism. Objective 4, expand the research to ascertain whether the requirement of DNA methylation dependent changes in the root associated microbiome for long-lasting stress memory is plant species specific. The knowledge gained from this fellowship will inform the breeding of novel crop varieties which display enhanced resistance to pests without the requirement to be exposed to stress. It will also direct the development of new soil management strategies which promote pest-resistance inducing microbes. Together these novel pest control strategies will help ensure sustainable production of our food which will benefit farmers, consumers, and the wider environment.

植物害虫和病原体对全球粮食供应构成重大威胁。农药是目前主要的控制策略，但有明确证据表明它们会对人类健康和更广泛的环境产生负面影响。为了确保我们的粮食供应可持续的未来，农业必须放弃对有害化学农药的依赖。增强植物抵抗毛毛虫等害虫的天然能力将有助于实现这一目标。在本次研究金中，我将破译植物免疫系统某一方面的机制，该机制具有巨大的开发潜力。在暴露于特定的环境刺激（例如轻微的害虫损害）后，植物对未来的攻击变得更有抵抗力。这种现象被称为获得性或诱导性抵抗，是压力记忆的一种。应激记忆的形成涉及植物表观基因组的变化，表观基因组是调节植物基因组的化学修饰的集合。在最近的一篇出版物中，我发现特定基因组区域的一种特定修饰（DNA 甲基化）的减少对于持久的压力记忆和对咀嚼食草动物的抵抗力至关重要。 DNA 甲基化的去除（DNA 去甲基化）也被证明可以通过控制根系分泌物的产生以及有益微生物的招募来影响植物根部相关的微生物组。这些最近的发现提出了一个尚未解答的重大问题：植物的应激记忆是否是由 DNA 甲基化和微生物组的结合支撑的？更具体地说，应激诱导的 DNA 甲基化缺失是否会调节植物根部有益微生物组的招募，这是否会促进应激记忆和持久抵抗力？在这个奖学金中，我将研究这些及时的问题，并产生关于植物逆境适应机制的革命性的新见解。该奖学金的研究计划将分为四个目标，利用重要作物品种番茄（Solanum lycopersicum；目标 1-3）和模式植物拟南芥（目标 4）来解决。目标 1，研究功能性土壤微生物组对植物在食草胁迫或使用诱导性 DNA 去甲基化系统去除 DNA 甲基化后表达持久诱导抗性的要求。目标 2，表征食草应激诱导的与应激记忆相关的根转录组的变化，并确定这是否会导致根分泌物和有益微生物组招募的长期变化。目标 3，证明食草应激会导致 DNA 甲基化丧失，并确定这是否调节根系分泌物代谢。目标 4，扩大研究范围，以确定根相关微生物组中 DNA 甲基化依赖性变化对持久胁迫记忆的要求是否具有植物物种特异性。从该奖学金中获得的知识将为新型作物品种的育种提供信息，这些作物品种无需暴露在压力下即可表现出增强的抗害虫能力。它还将指导开发新的土壤管理策略，以促进诱导微生物产生抗虫性。这些新颖的害虫防治策略将有助于确保我们食品的可持续生产，从而使农民、消费者和更广泛的环境受益。