雨生红球藻是天然虾青素理想来源，其规模化养殖仍面临生长慢、虾青素得率低等瓶颈。为获得用于生产的理想藻株，亟需找到虾青素合成的有效调控手段并厘清其调节机制。雨生红球藻虾青素合成的调控能发生在转录水平。通过转录组测序，我们找到了受到强光和高盐强烈诱导表达的转录因子：HpMYB1和HpHB1。它们具有什么样的生物学功能，如何调控虾青素的合成？又通过何种分子机制来进行转录调控？这些都将在本项目中得到回答。本项目拟通过RACE获得基因全长，通过EMSA揭示转录因子与虾青素合成关键酶基因启动子的相互作用，采用酵母单杂交分析转录因子的转录激活活性，通过突变体功能互补或在雨生红球藻中过量表达有效基因，分析其生物学功能。研究结果不仅为阐明虾青素合成的转录调控机制奠定科学基础，还将为优良藻种选育提供理论依据。

Haematococcus pluvialis is the ideal resource of natural astaxanthin. But its large-scale cultivation still faces low growth rate, low yield of astaxanthin, and other bottlenecks. To obtain the ideal algal strains for astaxanthin production, it is in urgent need of identifying effective regulatory factors of astaxanthin synthesis and clarify its regulation mechanism. In Haematococcus pluvialis, the astaxanthin biosynthesis is regulated at transcriptional level. Through RNA-seq, we have found two transcription factor: HpMYB1 and HpHB1 which strongly induced expressed under high-light and high-salt treatments. What is the biological functions of transcription factors HpMYB1 and HpHB1 in Haematococcus pluvialis? How dose HpMYB1 and HpHB1 regulate astaxanthin synthesis? By which molecular mechanism HpMYB1 and HpHB1 regulate astaxanthin synthesis? All the questions above will be answered after this project performed. The project prepares to use RACE to obtain complete gene of HpMYB1 and HpHB1. EMSA (Electrophoretic Mobility Shift Assay) will be employed to reveal the reaction between HpMYB1 or HpHB1 and the promoters of genes encoding key enzymes in astaxanthin biosynthesis in Haematococcus pluvialis. The yeast one-hybrid will be performed to determine the transcription activation of HpMYB1 and HpHB1. At the same time, we will analyze the biological functions of HpMYB1 and HpHB1 by over-expressing them in Haematococcus pluvialis and functional complementation in mutants. The study will not only set a scientific foundation for transcriptional regulation mechanism of astaxanthin biosynthesis, but also provide the theoretical basis for genetic breeding of fine algal species.