微藻响应营养胁迫信号经胞质重构进行储能物质积累的分子机制尚不清楚。蛋白聚泛素化是一种高度保守的调控方式。前期转录研究发现，缺氮胁迫时伴随储能物质积累泛素介导蛋白水解途径基因表达变化显著，推测蛋白聚泛素化在微藻储能物质代谢调控中起重要作用。本项目以野生型莱茵衣藻cc-124和突变株sta6为对象，利用聚泛素特异富集-μHPLC-MS/MS、基因敲除-回补等方法，结合细胞生理生化分析和免疫组化技术，进行：1)莱茵衣藻全局聚泛素化蛋白数据库构建及莱茵衣藻聚泛素化比较蛋白组学研究；2) 基于细胞生理生化和基因工程操作的关键聚泛素化蛋白识别与功能验证研究，从而深入阐释蛋白聚泛素化对微藻储能物质代谢调控的分子机理。本研究将丰富蛋白聚泛素化调控微藻代谢的基础理论，并将获得大量新的生物信息和材料，在工程微藻新性状理性设计、微藻合成生物学研究开展及新培养调控技术开发方面具有重要意义。

It's well known that most of microalgae accumulate energy storage materials under the nutrition deprivation, by way of cytoplasmic reassembly. But the mechanisms underlying is unknown. Polyubiquition is a highly conserved post-translation modification among eukaryotes, involving in almost every bioprocess in the cells. In our previous transcriptome study of microalgae, accompanying with the accumulation of energy storage materials, the genes in ubiquitin mediated proteolysis changed significantly. It's postulated that the polyubiquition plays an important role in regulation of the metabolism of energy storage materials. Here, the wild type stain of Chlamydomonas reinhardtii cc-124, as well as the starchless strain sta6 with ADP-glucose pyrophosphorylase defective mutation, was chosen as the model to investigate the shift of polyubiquition under the nitrogen deprivation and its effects on the regulation of energy storage material's metabolism, by way of comparative proteomocs analysis of polyubiquited proteins, gene knock out or RNAi, chemical and physiological analysis and immunostaining. In details, two approaches will be carried out: 1) the construction of database for polyubiquited proteins following the different stress stages and the comparative analysis of data, referring to KEGG pathway information, to distinguish the key polyubiquited proteins for verification and function prediction; 2) the "wet" verification of targeting proteins by way of immunostaining, chemical and physiological analysis and genetic operations. The goal of this project is to illustrate the molecular regulation mechanism of polyubiquition on the energy storage material's metabolism. The result of this project will enrich the knowledge of polyubiquition on the metabolism regulation, and will provide new bioinformation and materials for the future studies on the rational design of engineered strains, the synthetic biology based on microalgae and the new regulation technologies in the practice of large scale cultivation of microalgae.