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、卵菌和细菌是导致植物病害的主要原因，占全世界农作物总损失的三分之一以上。开发持久、广谱的抗病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。 本研究的目标是对马铃薯中天然寄主防御肽(HDPs)的性质及其在保护植物免受病原微生物侵染中的主要作用进行基础研究。这些肽，也被称为阳离子抗菌肽，代表着一个不同的小分子家族，膜活性分子存在于许多进化遥远的生物中，从原始无脊椎动物到植物和人类，被认为是抵御病原体入侵的天然防御系统的一部分。与其他防御分子相比，HDPs最重要和最独特的特征是它们针对微生物膜与动植物膜之间的根本设计差异，这使它们具有明确的优势。因此，与其他化合物相比，出现抗药性菌株的可能性较小。 本研究的创新之处包括利用天然植物防御肽开发马铃薯广谱抗病基因、验证天然植物防御肽作为植物天然免疫调节剂的假说、不同HDP编码基因在同一植物中的同时表达(基因聚合)、诱导表达和器官特异性表达，以及探索马铃薯块茎作为生产治疗性植物防御肽的低成本、安全和有效的平台的适宜性。这项研究将阐明HDP介导植物抗病的分子机制(S)，包括HDP的作用方式及其抗菌活性所必需的结构基序，它们在寄主植物内的细胞内定位和运输，并将阐明HDP在植物功能中其他未知的作用，从而提高植物生产力和产量。 这项拟议的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作为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改善食品安全。此外，这种方法可能对提高其他作物的抗病能力有用。最后，参与这一独特研究计划的HQP将获得各种实验学习机会，这对他们未来在学术界、政府和行业的职业生涯至关重要。