Nitric oxide turnover and the strategy of physiological adaptation of plants to low oxygen stress

我的研究项目旨在建立一氧化氮（NO）的产生和清除机制，以及NO代谢在植物适应洪水期间普遍发生的低氧胁迫中的功能作用，并造成农业生产的重大损失。洪水导致根系缺氧，因此在逆境下维持植物的代谢活动对其生存至关重要。目前的项目旨在确定缺氧产生的NO在洪水、种子萌发和快速生长组织中低氧条件下的初级代谢和信号转导调节中的生理作用。这项研究将为缺氧生存期间与碳水化合物和ATP的控制使用相关的代谢调节以及亚硝酸盐作为线粒体中替代电子受体的潜在使用提供新的见解。本研究旨在建立一氧化氮转化在调控植物细胞氧化还原和能量水平中的新作用，并确定与高效清除一氧化氮相关的防御机制在调控基因表达和维持基因组稳定中的重要性。从诱导植物清除和利用这些有毒化合物的机制的角度，研究活性氮（RNS）如NO和亚硝基谷胱甘肽与活性氧（ROS），特别是超氧自由基和过氧化氢之间的串扰。该研究将在确立NO代谢作为经典发酵途径的替代途径方面具有预期的意义，它在维持细胞氧化还原态和控制细胞程序性死亡、通气组织形成和不定根生长等形态发生事件方面具有重要意义。本研究的实际价值在于制定应对植物厌氧事件负面后果的策略和种子萌发的调控。一氧化氮代谢是植物长期提高抗逆性的一个新的潜在靶点。

My research program aims to establish the mechanisms of nitric oxide (NO) production and scavenging and the functional role of NO metabolism in plants in their adaptation to low oxygen stress taking place widespread during flooding and causing significant losses of agricultural production. Flooding leads to oxygen deprivation in roots, so the maintenance of metabolic activity in plants under stress is essential for their survival. The current project is targeted to define the physiological role of hypoxically produced NO in the regulation of primary metabolism and signal transduction in conditions of low oxygen taking place upon flooding, during seed germination and in fast-growing tissues. The investigation will provide new insights into the metabolic adjustments associated with the controlled use of carbohydrates and ATP during hypoxic survival and the potential use of nitrite as an alternative electron acceptor in mitochondria. The suggested research program aims to establish novel roles of NO turnover in regulating redox and energy levels in stressed plant cells and to determine the importance of defense mechanisms related to efficient NO scavenging in regulating gene expression and maintaining genome stability. The cross-talk between reactive nitrogen species (RNS) such as NO and nitrosoglutathione and reactive oxygen species (ROS) that include, in particular, superoxide radical and hydrogen peroxide will be investigated from the point of view of induction of the mechanisms supporting beneficial scavenging and utilization of these toxic compounds for plant survival. The proposed research will have expected significance in establishing NO metabolism as an alternative to classic fermentation pathways, its importance in the maintenance of cell redox status and in governing morphogenetic events which include programmed cell death, aerenchyma formation, and growth of adventitious roots. The practical value of this study consists in developing the strategies of coping with negative consequences of anaerobic events in plants and in regulation of seed germination. Nitric oxide metabolism represents a new potential target for long-range improvement of resistance to stress in plants.