Regulation of adaptive responses to flood-induced hypoxia in Marchantia polymorpha

地钱对洪水缺氧的适应性反应的调节

基本信息

批准号：
BB/X001059/1
负责人：
Francesco Licausi
金额：
$ 73.4万
依托单位：
University of Oxford
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2023
资助国家：
英国
起止时间：
2023 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FX001059%2F1
关键词：
Regulation adaptive responses flood induced

项目摘要

Similar to animals, plants need oxygen to respire and thrive in their habitat. When exposed to light, plants release oxygen from water molecules through the green tissues that perform photosynthesis. However, conditions that limit gas diffusion, such as flooding, cause a dramatic reduction in oxygen availability. This leads to a stressful situation that diminishes crop productivity, when not directly causing death of the plants. In the UK, flood events such as those of Summer 2007 that hit the North Eastern England and the West Midlands, and of winter 2013/14 that affected Yorkshire and Somerset have been estimated to cause an economic damage to agriculture of over £84 million. In some cases, costs have exceeded £200,000 per farm. Economies of developing countries are even more sensitive to such events (Shresta et al. 2018). Considering this, flooding stress play a major more, along environmental factors, to limit agriculture yield worldwide and restricts the possibility to feed the human population, especially when considering its rapid growth, estimated to reach 9 bn within the next 30 years.Together with the University of Nottingham, my team characterized the mechanism by which plants measure the oxygen concentration available in the environment and activate adaptive response in time to cope with this stress. Using Arabidopsis thaliana as a model plant species, we discovered an enzyme conserved with animals and fungi that controls the abundance of regulatory protein that mediate the molecular response to low oxygen. Moreover, we and colleagues from Australia have provided evidence that the cellular energy powerplants, the mitochondria, also participate to signal the need to activate an adaptive response via regulatory protein called ANACs. These are normally bound to cellular membranes from which they are rapidly released in case of stress, to enter cell nuclei and induce the synthesis of proteins required to face the stress.Land plants derive from aquatic ancestors that colonized emerged lands about 500 M years ago. This big change of ambient feature drove plant evolution towards that enabled to exploit the opportunities and overcome the limitations of nonaquatic environments. These innovations have led land plant to development specialized features that ensure their success and fitness in environments characterized by strong fluctuations in water and oxygen availability. Liverworts, such as Marchantia polymorpha, thrive in humid habitats and yet we found them extremely sensitive to prolonged submergence, while Arabidopsis colonized a range of environments. These species largely differ under several aspects of their physiology, and thus we expect them to use alternative strategies to cope with low oxygen. We believe that the identification of differences and similarities in this process across plant species with such divergent morphology and ecology holds untapped potential to the discovery of useful and yet unknown pathways to response to oxygen fluctuations and activate response that protect from oxidative stress and allow metabolic adjustments to cope with hypoxia.In summary, we will study the response to hypoxia in the two species (Marchantia and Arabidopsis) by means of state-of-the-art technologies and applying the most recent molecular analytic techniques. By doing so, we envisage to identify and characterize the molecular mechanisms involved in oxygen perception and oxidative stress signalling in plants. We will compare the mechanisms set into place in Marchantia and Arabidopsis, and exploit the strategy to induce or repress each mechanism in both model species, to identify those essential or more effective to protect plants from flooding stress. Our final aim is the identification of key elements or pathways that can be effectively transferred to crop species to improve their submergence tolerance.

与动物类似，植物需要氧气才能在其栖息地中呼吸和繁衍生息，当植物暴露在光下时，它们会通过进行光合作用的绿色组织从水分子中释放氧气，但是，限制气体扩散的条件（例如洪水）会导致氧气急剧减少。在英国，2007 年夏季和冬季袭击英格兰东北部和西米德兰兹的洪水事件不仅会导致作物生产力下降，还会导致氧气供应紧张。据估计，2013/14 年影响约克郡和萨默塞特的农业经济损失超过 8,400 万英镑，在某些情况下，每个农场的损失甚至超过 20 万英镑（Shresta 等）。考虑到这一点，洪水压力与环境因素一起，限制了全球农业产量，并限制了养活人口的可能性，特别是考虑到其快速增长。未来 30 年内将达到 90 亿。我的团队与诺丁汉大学一起，以拟南芥为模型，描述了植物测量环境中可用氧气浓度并及时激活适应性反应以应对这种压力的机制。在植物物种中，我们发现了一种在动物和真菌中保守的酶，它控制介导对低氧的分子反应的调节蛋白的丰度。此外，我们和来自澳大利亚的同事提供的证据表明，细胞能量发电厂线粒体也参与了调节蛋白的调控。信号需要通过称为 ANAC 的调节蛋白激活适应性反应。这些蛋白通常与细胞膜结合，在遇到压力时会迅速释放，进入细胞核并诱导面对压力所需的蛋白质的合成。源自大约 5 亿年前在陆地上定居的水生祖先，这种环境特征的巨大变化推动了植物的进化，使其能够利用机会并克服非水生环境的局限性。他们的成功和地钱（例如地钱）在潮湿的栖息地中茁壮成长，但我们发现它们对长期淹没极为敏感，而拟南芥则在一系列环境中存在很大差异。因此，我们希望它们能够使用替代策略来应对低氧。我们相信，识别具有如此不同形态和生态的植物物种在这一过程中的差异和相似之处，具有尚未开发的潜力。发现有用但未知的响应氧气波动的途径和激活的反应，以防止氧化应激并允许代谢调整以应对缺氧。总之，我们将通过以下方法研究两个物种（地钱属和拟南芥）对缺氧的反应：通过使用最先进的技术并应用最新的分子分析技术，我们设想识别和表征植物中氧气感知和氧化应激信号传导的分子机制。在地钱属和拟南芥中实施，并利用该策略诱导或抑制这两种模式物种中的每种机制，以确定那些对于保护植物免受洪水胁迫至关重要或更有效的机制。我们的最终目标是确定可以发挥作用的关键元素或途径。有效地转移到作物物种中以提高其耐淹性。