Rate-limiting steps in photorespiratory metabolism and their importance for metabolic regulation

光合作用和光呼吸作用形成一个重叠的反应网络，其中光呼吸C2循环通常被认为是一个相当不受调节的代谢过程。同样，这两个过程之间的监管互动也没有得到很好的分析。我们的小组计划确定光呼吸碳通量的代谢限制，并分析其潜在的调节途径内的重要性和CB循环的反馈调节。为此，我们正在研究一系列突变体和过表达株系的光呼吸和相关代谢和转录过程的改变，以表征内部和跨网络碳通量和其他相互作用。收集的定量数据用于开发光呼吸代谢的计算模型，并用于进一步改进和询问模型。在第一个项目期间，假设的光呼吸途径和CB循环的反馈调节可以得到证明，并与其他主要代谢途径的相互作用。在下一个阶段，重点将是完成多层次的表型研究和功能解剖的确定的监管现象。

Photosynthesis and photorespiration form an overlapping reaction network in which the photorespiratory C2 cycle is generally regarded as a rather unregulated metabolic process. Similarly, regulatory interactions between the two processes have not been well analysed. Our group plans to identify metabolic constraints to photorespiratory carbon flux and analyse their potential regulatory importance within the pathway and for feed-back regulation of the CB cycle. To this end, we are examining a range of mutants and overexpressor lines for alterations in photorespiratory and related metabolic and transcriptional processes to characterize internal and cross-network carbon fluxes and other interactions. Collected quantitative data serve to develop a computational model of photorespiratory metabolism and used for further improvement and interrogation of the model. In the first project period, the hypothesized feedback regulation from the photorespiratory pathway and the CB cycle could be proven and interactions with other major metabolic pathways shown. In the next period, focus will be on the completion of the multi-level phenotyping studies and the functional dissection of the identified regulatory phenomena.