Mechanisms of Pathogenicity and Host Specificity of the Oomycete Plant Pathogen Phytophthora palmivora

卵菌类植物病原棕榈疫霉的致病机制和寄主特异性

• 批准号: 2303713
• 负责人: Miaoying Tian
• 金额: $ 22.5万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2303713&HistoricalAwards=false
• 关键词: Mechanisms; Pathogenicity; Host; Specificity; Oomycete

Phytophthora palmivora is a fungus-like eukaryotic microorganism that causes devastating diseases of numerous agriculturally and ecologically important plants, including cacao, a tropical perennial tree that produces the major component of the multi-billion-dollar chocolate industry. The annual global loss on cacao due to diseases caused by P. palmivora is at least one billion U.S. dollars. As a very aggressive pathogen, P. palmivora is often capable of infecting almost all plant parts of a host, rendering its control extremely challenging. As a result, it has become an increasing threat to agricultural production and ecosystems. Diseases caused by P. palmivora are managed by frequent application of fungicides with limited success. The long-term goal of this project is to develop novel, effective and environmentally friendly strategies to control P. palmivora based on the fundamental understandings of its infection mechanisms. To this end, the specific objectives of this project are to identify the key pathogenicity factors of P. palmivora, how these factors act on plant cellular components to contribute to disease, and how their presence/absence in a P. palmivora isolate determines which plant species to infect. This project is expected to generate significant foundational knowledge essential for developing desirable disease control measures, thereby significantly contributing to food security, sustainability of natural ecosystems and the bioeconomy. In addition, the project will contribute to STEM workforce sustainability by providing training opportunities to graduate, undergraduate and high school students, and introducing plant pathology and gene-editing technology to middle/high-school teachers to attract a new generation into agriculture and life sciences. Oomycetes form a distinct phylogenetic lineage of eukaryotes, with many causing devastating diseases of plants and animals. Phytophthora palmivora is a destructive broad-host-range oomycete plant pathogen with host specificity. P. palmivora delivers a diverse array of effectors to manipulate the host cellular processes to facilitate infection, including the superfamily of RxLR effectors that are defined by an N-terminal signal peptide followed by a canonical RxLR (or RxLR-EER) translocation motif that mediates entry into host cells. The P. palmivora RxLR effector designated PpalRxLR1 contains a functional nuclear localization signal with potential DNA-binding activities and was identified as a key pathogenicity factor on cacao. It is present in all examined P. palmivora isolates obtained from cacao infections, but exhibits presence/absence polymorphisms across the species, suggesting that it may be a determinant of host range and specificity. This project is to: 1) determine the mechanisms by which PpalRxLR1 confers pathogenicity on cacao by determining its nuclear-localized molecular interaction dynamics and the subverted host cellular processes during infection, 2) determine the role of PpalRxLR1 as a key component in host range evolution of P. palmivora by analyzing its evolution relative to the species and association with host range, 3) identify additional effectors with key roles in pathogenicity of P. palmivora on specific or a broad range of hosts using the natural variation of P. palmivora isolates. Integrating across specific aims is expected to transform understanding of the molecular basis of pathogenicity and host range evolution of P. palmivora, key aspects of plant-microbe interactions.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.

Phytophthora Palmivora是一种真菌样真核微生物，可引起许多农业和生态上重要的植物的毁灭性疾病，包括Cacao，包括Cacao，Cacao，Cacao，这是一种热带多年生树，它产生了数量千美元的巧克力行业的主要成分。由于帕尔帕里瓦拉造成的疾病而导致的可可的年度全球损失至少为10亿美元。作为一种非常侵略性的病原体，帕Palmivora通常能够感染宿主的几乎所有植物部分，从而使其控制极具挑战性。结果，它已成为对农业生产和生态系统的越来越多的威胁。由棕榈假单胞菌引起的疾病是通过频繁应用杀真菌剂而成功的，成功的疾病。该项目的长期目标是制定新颖，有效且对环保的策略，以基于对其感染机制的基本理解来控制棕榈假单。为此，该项目的具体目标是确定棕榈假单疟原虫的关键致病因素，这些因素如何作用于植物细胞成分有助于疾病的作用，以及它们在棕榈疟原虫分离株中的存在/不存在如何确定哪些植物物种感染了哪些植物物种。预计该项目将为制定理想的疾病控制措施产生重要的基础知识，从而显着促进粮食安全，自然生态系统的可持续性和生物经济学。此外，该项目将通过为毕业，本科和高中生提供培训机会，并将植物病理学和基因编辑技术介绍给中/高中老师，从而吸引新一代农业和生命科学，从而为STEM劳动力的可持续性做出贡献。卵菌形成了真核生物的独特系统发育谱系，许多人引起了动植物的毁灭性疾病。 Phytophthora Palmivora是一种具有宿主特异性的破坏性的宽宿主型卵形植物病原体。 P. Palmivora提供各种效应子来操纵宿主细胞过程以促进感染，包括由N端信号肽定义的RXLR效应子的超家族，然后是规范的RXLR（或RXLR-EER）介导进入宿主细胞的易位序列。帕内维氏疟原虫RXLR效应子指定的PPALRXLR1包含具有潜在DNA结合活性的功能性核定位信号，并被确定为可可的关键致病因素。它存在于从可可感染中获得的所有检查的棕榈杆菌分离株中，但在整个物种中都表现出存在/不存在多态性，这表明它可能是宿主范围和特异性的决定因素。该项目是：1）确定PPALRXLR1通过确定其核位分子相互作用动力学和颠覆性宿主细胞过程的ppalRXLR1赋予对可可的致病性，2）确定PPALRXLR1在PPALRXLR中确定PPALRXLR1的作用，并通过分析宿主范围的相对范围，并将其与P. Palmivora的宿主进化相关范围相关，并确定pmalivora的相关范围，从而确定p. Palmivora的相关范围的相关范围。棕榈假单胞菌在特异性或广泛的宿主中使用棕榈叶疟原虫分离株的自然变异中的作用。预计整合特定目标将改变对致病性的分子基础的理解和帕尔帕利亚假单胞菌的宿主范围的演变，植物 - 微生物相互作用的关键方面。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的审查标准来通过评估来通过评估来支持的。