雨生红球藻是生产“天然抗氧化剂”—虾青素的优质原料，是目前研究得最多、最有开发潜力的微藻之一。利用雨生红球藻生产虾青素的关键问题是提高藻的生长速度和虾青素含量。针对以上问题，本项目拟研究：（1）雨生红球藻碳代谢关键酶—Rubisco、Rubisco活化酶和碳酸酐酶的基因克隆及其在不同环境条件下的转录表达规律。从蛋白和基因水平上比较3种酶与藻生长的相关性。（2）利用高通量测序技术对雨生红球藻进行生物量积累期和虾青素积累期转录谱的差异比较，结合RT-PCR技术分析雨生红球藻生长和虾青素积累相关基因的表达特征。建立雨生红球藻遗传转化体系,对目标基因进行功能研究。（3）研究不同环境胁迫条件下雨生红球藻的转录谱差异。重点研究藻生长和虾青素合成相关10-20个基因，结合基因注释信息和KEGG代谢分析，构建雨生红球藻中虾青素合成代谢网络，初步阐明虾青素积累关键基因对外界刺激的响应机制。

Haematococcus pluvialis (Chlorophyta) is an excellent material to accumulate natural astaxanthin, which is a kind of natural antioxidant, so the alga has become one of the most and potential microalgae at present. The current problem is to improve the algal growth rate and astaxanthin content. This project will focus on the above problems: (1) Three carbon metabolism key enzymes of Rubisco, Rubisco activase and carbonic anhydrase in H. pluvialis will be cloned, and their transcription variation under different conditions will be elucidated. Thus, the correlation of three enzymes and algal growth will be compared on the protein and gene levels. (2) The transcriptome will be performed in H. pluvialis by high throughput sequencing technology. The expression profiles of related genes between biomass and astaxanthin accumulation periods will be elucidated by combining with transcriptome and RT-PCR analysis. The genetic transformation system in Haematococcus pluvialis will be constructed, and the function investigation of key genes will performed. (3) The difference of transcriptome will be investigated under different environmental stress, and 10-20 astaxanthin synthesis-related genes will be studied in H. astaxanthin. Through combining with the gene annotation information and KEGG metabolism analysis, the astaxanthin synthetic metabolic networks in H. pluvialis will be constructed, and the preliminarily mechanism of the key genes for astaxanthin accumulation response to outside stimuli will be clarified.