Discovering novel components and mechanisms of plant oxygen-sensing

发现植物氧传感的新成分和机制

• 批准号: BB/W013967/1
• 负责人: Michael Holdsworth
• 金额: $ 63.33万
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FW013967%2F1
• 关键词: Discovering; novel; components; mechanisms; plant

This application describes work that will transform our understanding of the biochemistry of plant oxygen-sensing. Oxygen is a key molecule for aerobic organisms, and oxygen-sensing is a central component of multicellular eukaryote biology. Reduced oxygen levels (hypoxia) due to flooding or waterlogging greatly reduce crop yields, and these important abiotic stresses are increasing in frequency and intensity due to climate change. Recently, in our lab and others, many novel roles for oxygen sensing have been defined in plants. Defining the complete biochemical mechanism of plant oxygen-sensing is an essential prerequisite to providing breeding or biotechnological approaches to stabilise yield in response to flooding and waterlogging. Along with others, we discovered a mechanism of plant oxygen sensing a decade ago, showing that oxygen-required degradation of key regulatory transcription factors controlled plant responses to hypoxia (Gibbs et al Nature 2011). We then showed that genetically enhancing oxygen-sensing in barley increased tolerance to waterlogging (Mendiondo et al Plant Biotechnology Journal 2016), demonstrating that our fundamental biochemical genetic approaches could be translated to address this agricultural problem. The pathway of oxygen-sensing, the PCO N-degron pathway, shares similarity to that of the animal Hypoxia Inducible Factor (HIF) system (that won the 2019 Nobel prize for Medicine and Physiology), including proteasomal destruction of transcription factors following covalent attachment of oxygen via dioxygenase enzymes, though the mechanisms are not related. Unlike the animal HIF system several core mechanisms and components of the plant oxygen-sensing pathway are not resolved. As animals also have an equivalent of the PCO (in animals ADO) N-degron pathway, these aspects are also unresolved in animal biology. This proposal seeks to fill these important knowledge gaps by addressing major inconsistencies between the currently accepted model for plant oxygen sensing and experimental evidence. In the proposed work we will discover new components and mechanisms of the core plant oxygen-sensing system (this will also provide information for the equivalent components and mechanisms of the animal ADO N-degron pathway). By providing new information that will completely redefine the PCO N-degron pathway (that we also showed acts as a mechanism of plant nitric oxide sensing; Gibbs et al Molecular Cell 2014), the work will facilitate the creation of novel resources and approaches to address agronomic problems associated with multiple abiotic stress tolerance, including flooding/waterlogging and salinity/drought. The project will involve a combination of inter-disciplinary experimental approaches spanning synthetic peptide synthesis, Mass Spectrometry, enzymology, genetics and plant physiology, only possible through the proposed collaboration of biologists and chemists. The project therefore provides great potential for novel interdisciplinary training. The proposed work is timely, building on our preliminary data and very recent publications by the project team and others in related fields, and offers the opportunity to resolve all the components of the pathway and defining their functions in this mechanism so essential for plant growth, development and response to environmental stresses.

该应用描述了将改变我们对植物氧气生物化学的理解的工作。氧是有氧生物的关键分子，氧气是多细胞真核生物生物学的核心成分。由于洪水或供水导致的氧气水平（缺氧）降低，大大降低了农作物的产量，并且由于气候变化而引起的这些重要的非生物胁迫正在增加频率和强度。最近，在我们的实验室和其他实验室中，已经在植物中定义了许多新型的氧气传感作用。定义植物氧气的完整生化机制是提供繁殖或生物技术方法以响应洪水和水池的稳定产量的必要先决条件。与其他人一起，我们发现了十年前的植物氧气传感的机理，表明氧气频繁的关键调节转录因子的降解控制了植物对缺氧的反应（Gibbs等人自然2011）。然后，我们表明，大麦中遗传增强的氧气提高了对养水的耐受性（Mendiondo等人植物生物技术杂志2016），这表明我们的基本生化遗传方法可以转化以解决这一农业问题。 PCO N-Degron Pathway的氧气感应途径与动物缺氧诱导因子（HIF）系统的相似性（赢得了2019年诺贝尔医学和生理学奖），包括通过dioxygenase enzymes的氧气附着的蛋白酶体破坏，包括氧气的转录因子的转录因子，这是不相关的。与动物HIF系统不同，未解决植物氧气途径的几种核心机制和成分。由于动物也具有相当于PCO（在动物中）N-Degron途径，因此这些方面在动物生物学中也无法解决。该提案旨在通过解决当前接受的植物氧气感应模型与实验证据之间的主要矛盾来填补这些重要的知识差距。在拟议的工作中，我们将发现核心植物氧密度系统的新组件和机制（这还将为动物Ado n-Degron途径的等效组件和机制提供信息）。 By providing new information that will completely redefine the PCO N-degron pathway (that we also showed acts as a mechanism of plant nitric oxide sensing; Gibbs et al Molecular Cell 2014), the work will facilitate the creation of novel resources and approaches to address agronomic problems associated with multiple abiotic stress tolerance, including flooding/waterlogging and salinity/drought.该项目将涉及跨学科实验方法的结合，这些实验方法涵盖合成肽合成，质谱，酶学，遗传学和植物生理学，只有通过提出的生物学家和化学家的合作才有可能。因此，该项目为新颖的跨学科培训提供了巨大的潜力。拟议的工作是及时的，基于我们的初步数据以及项目团队和相关领域的其他工作的最新出版物，并提供了解决途径的所有组成部分的机会，并在这种机制中定义其功能，这对于植物的生长，发展和对环境压力的反应至关重要。