Host defense peptides and mechanisms of broad-spectrum disease resistance in plants.

宿主防御肽和植物广谱抗病机制。

• 批准号: RGPIN-2019-07157
• 负责人: Yevtushenko, Dmytro
• 金额: $ 1.68万
• 依托单位: University of Lethbridge
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=716318
• 关键词: Host; defense; peptides; mechanisms; broad

Pathogenic fungi, oomycetes, and bacteria are the leading cause of plant diseases, contributing to more than one-third of total crop losses throughout the world. Development of plants with durable, broad-spectrum disease resistance is one of the greatest challenges in continuing to meet current and future world food needs. The goal of this research program is to conduct fundamental studies of the properties of natural host defense peptides (HDPs) in potatoes, and their primary roles in the protection of plants against pathogenic microorganisms. These peptides, also called cationic antimicrobial peptides, represent a diverse family of small, membrane-active molecules that are found in many evolutionarily distant organisms, ranging from primitive invertebrates to plants and humans, and are thought to be part of the innate defense system against pathogen invasion. The most important and unique feature of HDPs, which gives them a well-defined advantage over other defensive molecules, is that they target the fundamental design differences between microbial membranes and the membranes of plants and animals. Therefore, the emergence of resistant strains of the pathogens is less probable compared to that of other compounds. The novelty of this research includes the development of broad-spectrum disease resistance in potato using natural plant defense peptides (HDPs), testing hypothesis of HDPs as immunomodulators in plant innate immune response, simultaneous expression of different HDP-coding genes in one plant (gene pyramiding), induced and organ-specific expression of HDPs, and exploring the suitability of potato tubers as low cost, safe, and effective platform for the production of therapeutic HDPs. The research will elucidate the molecular mechanism(s) of HDP-mediated disease resistance in plants, including the mode of action of HDPs and their structural motifs essential for antimicrobial activity, their intracellular localization and transport within the host plant, and will clarify other, unknown roles of HDPs in plant functions that result in improved plant productivity and higher yield. The immediate impact of this proposed research program to Canada is that the resulting potato genotypes can be used as a source of valuable defense genes (germplasm) in conventional potato breeding programs. Other benefits include higher yields, reduced post-harvest losses, and improved food safety due to lower level of fungal toxin contaminants. In addition, this approach may be useful to improve disease resistance in other crops. Finally, HQP involved in this unique research program will be exposed to a variety of experimental learning opportunities, essential for their future careers in academia, government, and industry.

病原真菌、卵菌和细菌是植物病害的主要原因，占全世界作物总损失的三分之一以上。开发具有持久、广谱抗病性的植物是继续满足当前和未来世界粮食需求的最大挑战之一。 该研究计划的目标是对马铃薯中天然宿主防御肽（HDPs）的性质及其在保护植物免受病原微生物侵害中的主要作用进行基础研究。这些肽，也称为阳离子抗菌肽，代表了在许多进化上遥远的生物体中发现的小的膜活性分子的多样化家族，从原始无脊椎动物到植物和人类，并且被认为是抵抗病原体入侵的先天防御系统的一部分。HDPs最重要和独特的特征，使它们比其他防御分子具有明确的优势，是它们针对微生物膜与植物和动物膜之间的基本设计差异。因此，与其他化合物相比，病原体的耐药菌株的出现的可能性较小。 本研究的创新之处在于利用天然植物防御肽（HDPs）开发马铃薯的广谱抗病性，验证HDPs作为植物天然免疫应答的免疫调节剂的假说，以及在同一株植物中同时表达不同的HDPs编码基因通过基因工程技术，诱导和器官特异性表达HDPs，探索马铃薯块茎作为低成本、安全、和生产治疗性HDPs的有效平台。该研究将阐明HDP介导的植物抗病性的分子机制，包括HDP的作用模式及其对抗菌活性至关重要的结构基序，它们在宿主植物中的细胞内定位和运输，并将阐明HDP在植物功能中的其他未知作用，从而提高植物生产力和产量。 这项研究计划对加拿大的直接影响是，由此产生的马铃薯基因型可以用作传统马铃薯育种计划中有价值的防御基因（种质）的来源。其他好处包括更高的产量，减少收获后的损失，以及由于真菌毒素污染物水平较低而提高食品安全性。此外，这种方法可能有助于提高其他作物的抗病性。最后，参与这一独特研究计划的HQP将接触到各种实验学习机会，这对他们未来在学术界，政府和工业界的职业生涯至关重要。