金色奥杜藻（Odontella aurita）岩藻黄素代谢对光质变化的响应及信号分子的转录调控机制

岩藻黄素是硅藻合成的一种具有抗炎、抗氧化、抗肿瘤和抗肥胖等活性功能的光合色素，在医药保健领域具有广泛的应用前景。本项目以法国引进的工业藻种金色奥杜藻（Odontella aurita）为对象，以光质调控为手段，研究岩藻黄素代谢的光质响应及其调控机制。首先，分析不同光质下金色奥杜藻生长和岩藻黄素含量变化，筛选适合岩藻黄素高效积累的最佳光质条件。然后，分析不同代谢路径基因的表达差异，考察光质对岩藻黄素代谢基因在转录水平上的调控。最后，分析信号分子活性氧自由基（ROS）及其清除基因的转录表达，正向验证ROS与岩藻黄素代谢的关系；使用光合作用抑制剂二氯苯基二甲脲（DCMU）和2,5-二溴-3-甲基-6-异丙基对苯醌（DBMIB），反向验证信号分子质体醌的氧化还原状态与岩藻黄素代谢基因转录的关系。研究结果可揭示岩藻黄素代谢响应的物质基础和分子机制，为金色奥杜藻规模化培养的补光选择提供理论与实践依据。

Fucoxanthin is a photosynthetic pigment synthesized by diatom, which has the bioactive functions of anti-inflammatory, anti-oxidation, anti-tumor and anti obesity. It has a broad application prospect in the field of medicine and healthcare. In this project, Odontella aurita, an industrial microalga introduced from France, is taken as the object to study the mechanism of fucoxanthin metabolism responding to light quality changes. First of all, the growth, photosynthetic physiology and fucoxanthin content of O. aurit under different light quality were analyzed. The optimum light quality conditions for the efficient accumulation of fucoxanthin were selected. Then, the expression differences of genes in different metabolic pathways were analyzed to investigate the regulation of light quality on the transcription of fucoxanthin synthesis genes. Finally, the intracellular reactive oxygen species (ROS), antioxidant enzyme activity and ROS scavenging related gene expressions were analyzed, and the relationship between ROS and the metabolism of fucoxanthin was verified; The relationship between the redox state of plastoquinone and the metabolism of fucoxanthin was verified by using the photosynthetic inhibitors 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU) and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB). The results can reveal the material basis and molecular mechanism of fucoxanthin metabolism response, and provide theoretical and practical basis for the selection of light supplement in large-scale cultivation of O. aurita.