外源褪黑素对盐胁迫下单针藻Monoraphidium sp.QLY-1油脂合成的影响

Effects of exogenous melatonin on lipid synthesis in Monoraphidium sp.QLY-1 under salinity stress

以单针藻Monoraphidium sp.QLY-1为研究对象,初步探索了不同浓度褪黑素对该藻在盐胁迫下油脂合成及相关基因表达、生理生化指标、胞内活性氧和谷胱甘肽的影响。结果表明,在10μmol/L褪黑素处理下,细胞中油脂含量达到51.74%,比盐胁迫组提高了1.21倍,同时,碳水化合物和蛋白质含量有所下降;褪黑素处理下油脂合成相关基因me和accD的表达水平是对照组的1.75和1.40倍;此外,外源褪黑素降低了藻细胞内活性氧的水平,缓解了盐胁迫导致的藻内氧化性损伤。在盐胁迫下,外源褪黑素可通过调控油脂合成基因及活性氧信号分子水平来进一步提高单针藻的油脂含量,该研究为提高微藻油脂合成提供了新的思路。

Taking Monoraphidium sp.QLY-1 as the research object,the effects of different concentrations of melatonin(MT)on the lipid content,expression of lipogenic genes,physiological and biochemical properties,as well as the intracellular levels of reactive oxygen species(ROS)and glutathione(GSH)under salinity stress were preliminarily investigated.The results showed that under 10μmol/L melatonin treatment,the lipid content of the cells reached 51.74%,which was 1.21 times higher than that of the salt stress group.Meanwhile,the protein and carbohydrate contents were both decreased as compared to the control.And the relative expression levels of me and accD,the lipid synthesis-related genes,were 1.75-and 1.40-folds higher than the control.Furthermore,the addition of MT reduced the levels of ROS and GSH in the algal cells,alleviating the oxidative damage caused by the salinity stress.These results suggested that MT could further promote the accumulation of lipid in microalgae under salinity stress by upregulating lipogenic genes and regulating oxidative stress,which provides a novel strategy for the synthesis of lipid in microalgae.