Plant immune signaling network: Connecting pathogen perception, chromatin modification and activation of immune responses.

植物免疫信号网络：连接病原体感知、染色质修饰和免疫反应激活。

• 批准号: 1916893
• 负责人: Tesfaye Mengiste
• 金额: $ 83.78万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1916893&HistoricalAwards=false
• 关键词: Plant; immune; signaling; network; Connecting

Plant pathogens are challenges to crop production. In particular, fungal pathogens cause destructive diseases that threaten global food, feed and fiber production and jeopardize diversity of plant species. Studies that expand fundamental knowledge on how plants fend off microbial infection is expected to help design better disease control strategies. Multifaceted molecular, biochemical and genomic approaches will be deployed to understand how plants regulation activation of defense against pathogens. Plants activate a battery of defense mechanisms including the synthesis of diverse antimicrobial agents and other immune responses to deter infection or restrict the extent of damage after infection. How plants activate or suppress these mechanisms will be studied. Knowledge on the temporal and spatial regulation of such changes are important to understand the mechanisms of disease resistance. The untimely activation of some of these immune responses in the absence of pathogens is not beneficial to the plant. Consequently a tight control of on timing and spatial activation is critical. The molecular and biochemical mechanisms underlying such defense gene activation, reprogramming, and how these occurs in the context of eukaryotic DNA that is packed with chromatin will be determined. The cellular communication that link pathogen sensing to the activation of defense in the plant cell will be analyzed. Discoveries from this project will expand basic knowledge, and pave the way to develop disease resistant plants. Finally, this project will train undergraduate, graduate students and post-doctoral scientists in plant molecular biology. Plant immune gene transcription is a major component of plant immunity with rapid and massive transcriptional programming occurring in response to pathogens. Changes in equilibrium of histone modifications mediated by histone modifying enzymes (HMEs) are critical players orchestrating these cellular responses. However, the mechanisms underlying transcription reprogramming in response to infection in the context of chromatin are not understood. This project is to dissect the signal transduction pathway connecting pathogen sensing to histone modifications, and the consequent dynamics in chromatin accessibility and transcription. The regulatory impacts of shifts in equilibrium of histone lysine methylations (HLMs) will be studied using histone methyl transferases and demethylases with antagonistic biochemical and functions. Molecular mechanisms and factors regulating events preceding reversible histone modifications and the subsequent changes in gene expression will be elucidated. Factors that regulate activation and recruitment of HMEs to target loci in response to infection to trigger shifts in HLMs and immune gene transcription will be studied. Transcription factors and nucleosome assembly proteins that are functional partners of HMEs in gene regulation will be analyzed. Aim1 focuses on regulation of HMEs by protein kinases, linking early events in immune responses to changes in chromatin state and gene expression. Aim2 is to characterize the functions of HME interacting transcription factors (TFs) and nucleosome assembly proteins. Aim3 is to determine genome wide gene expression profiles underlying shifts in equilibrium of HLM and decipher its biological impact. Discoveries from this project will improve basic knowledge and pave the way for epi-genome modifications of traits. Finally, this project will train undergraduate, graduate students and post-doctoral scientists.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

植物病原体是对作物生产的挑战。特别是，真菌病原体引起的破坏性疾病威胁到全球粮食、饲料和纤维生产，并危及植物物种的多样性。扩展植物如何抵御微生物感染的基础知识的研究有望帮助设计更好的疾病控制策略。多方面的分子，生化和基因组方法将被部署，以了解植物如何调节防御病原体的激活。植物激活一系列防御机制，包括合成多种抗菌剂和其他免疫反应，以阻止感染或限制感染后的损害程度。植物如何激活或抑制这些机制将被研究。了解这些变化的时空调控对了解抗病机制具有重要意义。在没有病原体的情况下，这些免疫反应中的一些不及时激活对植物是不利的。因此，严格控制时间和空间激活是至关重要的。这些防御基因激活、重编程的分子和生化机制，以及它们如何在填充染色质的真核DNA中发生，将被确定。将分析植物细胞中病原感知与防御激活之间的细胞通讯。这个项目的发现将扩展基础知识，并为培育抗病植物铺平道路。最后，培养植物分子生物学的本科生、研究生和博士后。植物免疫基因转录是植物免疫的一个重要组成部分，在对病原体的反应中发生快速而大量的转录编程。由组蛋白修饰酶（HMEs）介导的组蛋白修饰平衡的变化是协调这些细胞反应的关键参与者。然而，在染色质的背景下，转录重编程对感染的反应机制尚不清楚。该项目旨在剖析连接病原体感知和组蛋白修饰的信号转导途径，以及染色质可及性和转录的后续动态。利用具有拮抗生化和功能的组蛋白甲基转移酶和去甲基化酶，研究组蛋白赖氨酸甲基化平衡变化的调控影响。在可逆性组蛋白修饰和随后的基因表达变化之前调节事件的分子机制和因素将被阐明。在感染反应中，调节HMEs的激活和募集到靶位点的因子将引发hms和免疫基因转录的变化。转录因子和核小体组装蛋白是HMEs在基因调控中的功能伙伴。ai1关注蛋白激酶对HMEs的调控，将免疫反应的早期事件与染色质状态和基因表达的变化联系起来。目的2是表征HME相互作用转录因子（TFs）和核小体组装蛋白的功能。目的是确定HLM平衡变化背后的全基因组基因表达谱，并破译其生物学影响。这个项目的发现将提高基础知识，并为性状的外显基因组修饰铺平道路。最后，本项目将培养本科生、研究生和博士后科学家。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Improved pathogen and stress tolerance in tomato mutants of SET domain histone 3 lysine methyltransferases

• DOI: 10.1111/nph.18277
• 发表时间: 2022-06-17
• 期刊: NEW PHYTOLOGIST
• 影响因子: 9.4
• 作者: Bvindi, Carol;Lee, Sanghun;Mengiste, Tesfaye
• 通讯作者: Mengiste, Tesfaye