莱茵衣藻对MeJA处理的初期响应模式分析

深圳大学生命与海洋科学学院,深圳市海洋生物资源与生态环境科学重点实验室,广东省海洋藻类生物工程技术研究中心,广东深圳518071

代谢工程;代谢控制;莱茵衣藻;茉莉酸甲酯;类异戊二烯;2-甲基-D-赤藓糖醇4-磷酸途径;光合效率分析;转录分析

Analysis of the initial response pattern of Chlamydomonas reinhardtii to methyl jasmonate (MeJA) treatment
JIA Bin,LAN Chengxiang,and LI Xiangyu

College of Life Sciences and Oceanography, Shenzhen Key Laboratory of Marine Bioresources and Ecology, Guangdong Technology Research Center for Marine Algal Bioengineering, Shenzhen University, Shenzhen 518071, Guangdong Province, P. R. China

Key words : metabolic engineering; metabolic regulate; Chlamydomonas reinhardtii ; methyl jasmonate; isoprenoids; 2-C-methnatureyl-D-rythritol-4-phosphate (MEP) pathway; photosynthetic efficiency analysis; transcriptional analysis

DOI: 10.3724/SP.J.1249.2022.03237

备注

茉莉酸甲酯(methyljasmonate,MeJA)是植物次生代谢的调节剂,参与异戊二烯代谢调控,对莱茵衣藻的异戊二烯类物质合成有重要影响.为探究莱茵衣藻如何快速响应MeJA处理,测定MeJA处理下莱茵衣藻的生长状态和光合效率等生理特征参数,重点关注MeJA处理24h内2-C-甲基-D-赤藓糖醇-4-磷酸(2-C-methnatureyl-D-rythritol-4-phosphate,MEP)合成途径、类胡萝卜素合成途径和甾醇合成途径关键基因的表达水平变化.结果表明,MeJA处理降低了莱茵衣藻的生物量积累和光合活性,上调了MEP通路和甾醇合成通路相关基因,下调了类胡萝卜素合成途径的关键基因.在转录与生理层面,莱茵衣藻对于MeJA处理的初期响应具有快速与剂量依赖性的特点.研究结果为探索微藻类异戊二烯合成和代谢机制提供理论参考.
As a chemical elicitor of plants, methyl jasmonate (MeJA) is a regulator of many secondary metabolisms in plants, which participates in the regulation of isoprenoid metabolism and has an important impact on the synthesis of isoprenoids in Chlamydomonas reinhardtii ( C. reinhardtii ). In order to explore how C. reinhardtii responds rapidly to MeJA treatment, the physiological parameters such as growth rate and photosynthetic efficiency of C. reinhardtii under MeJA treatment were measured. The changes in the expression levels of key genes in the 2-C-methnatureyl-D-rythritol-4-phosphate (MEP) pathway and in the carotenoid and sterol synthesis pathway within 24 hours of MeJA treatment were focused. The results showed that MeJA treatment dramatically reduced biomass accumulation and photosynthetic activity of C. reinhardtii , prominently activated the expression of key genes in MEP pathway and sterol synthesis, inhibited key genes of carotenoid synthesis pathway. The results at the transcriptional and physiological levels suggested that the influence of MeJA on C. reinhardtii was rapid and dose-dependent. This study provides a theoretical reference for exploring the mechanism of isoprene synthesis and metabolism in microalgae.
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