Dynamic respiratory regulation in plant mitochondria

在植物中，线粒体呼吸对细胞的ATP供应、代谢产物的合成和有效的光合作用是至关重要的。灵活调节呼吸代谢的能力对于植物在多变的环境中保持生长发育尤为重要。线粒体呼吸的这种动态调节是如何实现的，人们知之甚少。在这项拟议的研究中，将研究呼吸对线粒体硫醇氧化还原状态和钙水平变化的反应。新的基因编码的荧光传感器将被开发来通过定量实时成像技术以高分辨率评估线粒体功能。模式植物拟南芥的体内显微镜将与体外和细胞器中的生化研究相结合，以监测线粒体氧化还原、钙和能量状态的变化，识别将硫醇氧化还原调节和钙动力学与呼吸联系起来的调节因子，并利用突变系剖析调控机制。根据现有的数据，将生成单个线粒体的呼吸动力学模型，以预测尚不清楚的调节特性。这些结果将为体内细胞器生物能量控制提供新的见解，并为深入了解植物中的线粒体调控打开大门。

In plants mitochondrial respiration is critical for cellular ATP provision, synthesis of metabolites and efficient photosynthesis. The ability to flexibly adjust respiratory metabolism is particularly important in plants to maintain growth and development in a changeable environment. The way in which such dynamic regulation of mitochondrial respiration is achieved is poorly understood. In the proposed research the regulation of respiration in response to changes in mitochondrial thiol redox status and calcium levels will be investigated. Novel genetically-encoded fluorescent sensors will be exploited to assess mitochondrial function with high resolution by quantitative live imaging techniques. In vivo microscopy of the model plant Arabidopsis will be combined with biochemical studies in vitro and in organello to monitor changes in mitochondrial redox, calcium and energy status, to identify regulators that link thiol redox regulation and calcium dynamics with respiration and to dissect control mechanisms using mutant lines. From the available data a model of respiratory dynamics in single mitochondria will be generated, to predict as yet unknown regulatory properties. The results will provide novel insights into organellar bioenergetic control in vivo and open the door to an in depth understanding of mitochondrial regulation in plants.