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

我的研究计划旨在建立一氧化氮(NO)的产生和清除机制，以及NO代谢在植物适应低氧胁迫中的功能作用。低氧胁迫在洪水期间广泛发生，并造成农业生产的重大损失。淹水会导致植物根部缺氧，因此维持植物在逆境下的代谢活动对它们的生存至关重要。本项目的目标是确定在淹水、种子萌发和快速生长组织中发生的低氧条件下，低氧产生的NO在调节初级代谢和信号转导中的生理作用。这项研究将为在低氧生存过程中控制碳水化合物和ATP的使用以及将亚硝酸盐作为线粒体电子受体的潜在用途提供新的见解。这项研究计划旨在确定NO代谢在调节逆境植物细胞氧化还原和能量水平中的新作用，并确定与有效清除NO相关的防御机制在调节基因表达和维持基因组稳定性方面的重要性。从诱导支持有益清除和利用这些有毒化合物为植物生存的机制的角度，将研究活性氮物种(RN)(如NO和亚硝基谷胱甘肽)与包括超氧阴离子自由基和过氧化氢在内的活性氧物种(ROS)之间的相互作用。这项拟议的研究将对建立NO代谢作为经典发酵途径的替代途径、其在维持细胞氧化还原状态和控制形态发生事件(包括细胞程序性死亡、通风组织形成和不定根生长)方面的重要性具有预期的意义。这项研究的实用价值在于开发应对植物中厌氧事件的负面后果的策略和调节种子萌发的策略。一氧化氮代谢是长期提高植物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.******