Relationship between sink-induced N remobilisation and seed filling in barley

只有在给种子提供最佳的碳氮同化物的条件下，才能达到高产和优质。在大麦中，近穗光合器官、旗叶和颖片是供给籽粒的重要器官。在灌浆过程中，碳和氮化合物从这些器官中被重新运输到灌浆籽粒中。了解这些过程可能有助于提高作物对氮的利用效率。本项目研究了大麦库诱导的氮再动员与籽粒灌浆之间的相互作用。我们计划对转录物和代谢物谱进行相关性和网络分析，以确定旗叶、颖片和籽粒中相应阶段的基因表达与代谢物浓度之间的关系。我们打算确定调控因子（基因产物，代谢物），控制再动员，籽粒灌浆及其相互作用。氨基酸转运体具有建立氮再动员/籽粒灌浆源（旗叶、颖片）和/或汇活性（籽粒）的潜在作用，将通过RNAi方法进行功能表征和验证。我们计划对现有的转基因大麦模型进行综合分析，以了解籽粒库强度的增加是否会对nrebilisation效率产生积极影响。在灌浆早期至中期进行显微解剖后，将对籽粒维管束进行代谢物/激素分析。我们打算分析代谢物在发育过程中的动力学，目的是确定那些具有潜在作用的代谢物，这些代谢物是谷物对来源的氮需求的信号。

High yield and grain quality can only be achieved at optimum supply of the seed with carbon and nitrogen assimilates. In barley, the ear-near photosynthesizing organs, flag leaf and glumes, are important for supplying the grain. During seed filling C and N compounds are remobilized from these organs and transported to filling grains. Understanding these processes can potentially contribute to crops with higher N-use efficiency. This project addresses the interactions between sink-induced N remobilization and grain filling in barley. We plan correlation and network analysis between transcript and metabolite profiles in order to identify associations between gene expression and metabolite concentrations at corresponding stages in flag leaves, glumes and grains. We intend to identify regulators (gene products, metabolites), which control remobilization, grain filling and its interactions. Amino acid transporters with a potential role establishing source (flag leaf, glume) and/or sink activity (grain) for N remobilization/grain filling will be functionally characterized and validated by RNAi approaches. We plan comprehensive analysis of available transgenic barley models to find out whether increased grain-sink strength can have positive impact on Nremobilisation efficiency. Metabolite/hormone analysis of the grain vascular bundle will be performed after micro-dissection during early to mid-grain filling. We intend to analyse dynamics of metabolites along development with the aim to identify those with a potential role signaling N demand of the grain to the source.