蓝藻中RNA修饰与代谢网络相互作用探索

蓝藻是一类可以进行产氧光合作用的细菌。基因改造后的蓝藻菌株可生产高不饱和脂肪酸，生物柴油等多种经济产物，是应用前景广泛的工程菌。蓝藻基因工程一般基于代谢网络改造代谢途径以增加目标终产物。但由于当前的蓝藻代谢工程研究主要依靠预测和筛选，需要对蓝藻的基础生理进行更深入的研究。.近年研究表明RNA水平的精细调控是物种复杂程度的重要体现。在信使RNA等生命元件上存在的RNA转录后修饰被证明在蛋白质的时空表达中起到重要调控作用。而这些RNA修饰的生物合成依赖于RNA修饰酶以及细胞内的代谢物，它们本身也被动态地调控于细胞内复杂的代谢网络之中。利用蓝藻研究代谢网络与RNA修饰相互作用是本项目的切入方向。.本项目拟基于质谱技术鉴定蓝藻工程菌株中RNA元件的核酸修饰并阐明它们的生物合成途径，深入研究它们与代谢网络的相互调控作用。

As one kind of widely distributed prokaryote performing oxygenic photosynthesis, cyanobacteria were genetically engineered to produce commodity chemicals such as highly unsaturated fatty acids (HUFA), polyhydroxyalkanoate (PHA) and biofuels. Generally, metabolic engineering of cyanobacteria is directed by information from the systematic network of metabolic pathways demonstrated in all kingdoms of life so far. However, still most engineering works must proceed based on prediction and screening, though we now have large-scale metabolic network databases like Kyoto encyclopedia of genes and genomes (KEGG) and Reactome. Further mechanisms of fine regulation of cyanobacteria metabolites should be studied.. Recent investigations uncovered the fact that not only the genome size of one creature reflects its complexity, but also precise controls in RNA levels play essential roles. Within which, post-transcriptional modifications on ribosomal (r) RNAs, messenger (m) RNAs and transfer (t) RNAs are being shown irreplaceable functions on regulating proteinic spatio-temporal expression. RNA modifications rely on RNA modifying enzymes and active chemical substrates, which are dynamically involved in the complicated metabolic network. The interaction between metabolites and RNA modifications in cyanobacteria is little known and what we aim to study.. In this project, we plan to start the identification work on post-transcriptional modifications on rRNAs, mRNAs, and transfer (t) RNAs in the cyanobacteria model strains along with their modifying enzymes. Deep research on uncovering the power of RNA modifications to fine regulation of the metabolic network will be performed.