PRJNA771997
De novo transcriptome of the flagellate Isochrysis galbana identifies genes involved in the metabolism of anti-proliferative metabolites
Haptophytes are important primary producer in the Oceans, and among the phylum Haptophyta the flagellate Isochrysis galbana has been found to be rich in high value compounds, such as lipids, carotenoids and high branched polisaccharides. These high value compounds possess several bioactivities including antioxidant, anticancer and immunomodulatory activities. In the present work I. galbana was cultured and collected both in stationary and exponential growth phase and then screened following a bioactivity-guided fractionation procedure in order to identify the most active algal fraction able to inhibit proliferation of specific human cancer cells. The most active fractions of the algae collected in stationary growth phase were the ones enriched in nucleoside, sterols and free fatty acid. The most active fraction of the algae collected in exponential growth phase were the ones enriched in glycolipids, phospholipids, sterols and fatty acids. A transcriptomic approach was used to analyzed also at gene level if there was an activation of the metabolic pathways responsible of the synthesis of the putative bioactive compounds. The whole transcriptome of I. galbana both in stationary growth phase and in exponential growth phase were analyzed. Differential expression analysis of samples collected at exponential versus stationary growth phase identified genes involved in lipid A biosynthetic process, glycero-phospholipid metabolic process, sterol biosynthetic process, ADP-ribose diphosphatase activity and other, confirming also at gene level the activation of metabolic pathways involved in the synthesis of compounds present in the enriched fractions.