Analysis of the initial response pattern of <italic>Chlamydomonas reinhardtii</italic> to methyl jasmonate (MeJA) treatment

Abstract

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 <italic>Chlamydomonas reinhardtii</italic> (<italic>C. reinhardtii</italic>). In order to explore how <italic>C. reinhardtii</italic> responds rapidly to MeJA treatment, the physiological parameters such as growth rate and photosynthetic efficiency of <italic>C. reinhardtii</italic> 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 <italic>C. reinhardtii</italic>, 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 <italic>C. reinhardtii</italic> was rapid and dose-dependent. This study provides a theoretical reference for exploring the mechanism of isoprene synthesis and metabolism in microalgae.