Impact of intracellular organelle positioing on metabolic performance and stress tolerance of Arabidopsis plants

植物的中枢代谢是特别灵活的，反映了植物需要定期修改自己的内部生理反应的发展和环境的变化。虽然代谢模型已经产生了植物代谢网络的理解，调节和分配通量的策略还没有充分理解到可观察到的植物代谢的多功能性。在翻译后水平，小分子相互作用，翻译后蛋白质修饰，和动态物理蛋白质协会支持当前的概念，代谢通量的调节。然而，最古老的代谢控制概念之一是将植物代谢划分为不同的细胞器。细胞器本身是移动的，它们相对于另一个细胞器的位置受到调节，并对外部条件作出反应。在这里，我们的目标是测试假设，细胞器定位，和代谢纳米结构域的产生结构的细胞代谢景观，支持效率，并提供一个新的层的监管。结合三个实验室的互补专业知识，我们使用合成方法来操纵和监测拟南芥细胞内线粒体和叶绿体的定位。我们将改变最近发现的一种糖酵解代谢物的稳定性，这种代谢物在物理上连接叶绿体和线粒体。我们将进一步控制细胞器协会诱导使用基因编码的SpyCatcher系统。为了抵消相互作用，我们将锚线粒体和叶绿体不同的细胞膜系统。为了探索细胞器定位对细胞代谢和植物性能的意义，我们将采用先进的代谢产物分析，通量分析和遗传编码的生物传感器以及表型分析，在不同的光合和光呼吸代谢状态下。我们将进一步在细胞器和其他膜的表面上构建蛋白质生物传感器，以评估细胞器的定位和关联如何塑造代谢梯度和纳米环境。植物细胞器的动态结构组织的意义，以调整代谢性能将建立。

Plant central metabolism is particularly flexible and reflects the need of plants to regularly modify their own internal physiology in response to developmental and environmental changes. While metabolic modelling has generated an understanding of the plant metabolic network, the strategies to regulate and allocate fluxes are not understood sufficiently well to account for the observable metabolic versatility of plants. At the posttranslational level, small molecule interaction, posttranslational protein modifications, and dynamic physical protein associations underpin current concepts of the regulation of metabolic fluxes. One of the oldest concepts of metabolic control, however, is compartmentation of plant metabolism into different organelles. The organelles themselves are mobile and their positioning relative to another is regulated and responsive to external conditions. Here, we aim to test the hypothesis that organelle positioning, and the generation of metabolic nano-domains structure the cellular metabolic landscape, support efficiency, and provide a novel layer of regulation. Combining the complementary expertise of three labs, we use a synthetic approach to manipulate and monitor the positioning of mitochondria and chloroplasts within Arabidopsis cells. We will alter the stability of a recently discovered glycolytic metabolon that physically links chloroplasts and mitochondria. We will further control organelle associations inducibly using the genetically encoded SpyCatcher system. To counteract interaction, we will anchor mitochondria and chloroplasts to different cellular membrane systems. To explore the significance of organelle positioning on cellular metabolism and plant performance we will employ advanced metabolite profiling, flux analyses and genetically encoded biosensors as well as phenotypic analyses, under different states of photosynthetic and photorespiratory metabolism. We will further immobilize protein biosensors on the surface of the organelles and other membranes to assess how organelle positioning and association shape metabolic gradients and nano-environments. The significance of dynamic structural organisation of plant cell organelles to adjust metabolic performance will be established.