De novo transcriptome of the cosmopolitan dinoflagellate Amphidinium carterae to identify genes with biotechnological interests. Amphidinium carterae

Dinoflagellates are phytoplanktonic organisms found in both freshwater and marine habitats. They are often studied because related to harmful algal blooms responsible for impacts on ecosystem functioning, economic damages for aquaculture and fishery industries and/or deleterious impacts for human health. In addition they are also known to produce bioactive compounds, such as for the treatment of cancer or beneficial effects for the treatment of Alzheimer’s disease. The dinoflagellate Amphidinium sp. is a cosmopolitan dinoflagellate species known to produce both cytotoxic and beneficial compounds. However, several studies reported that environmental changes (e.g. nutrient starvation, UV radiation and ocean acidification) may alter this production. The aim of this study was to sequence the full transcriptome of the dinoflagellate Amphidinium carterae in both nitrogen- starved and -repleted culturing conditions (1) to evaluated its response to nitrogen starvation, (2) to look for possible polyketide synthases (PKSs), involved in the synthesis of various compounds, in this studied clone, (3) if present, to evaluate if nutrient starvation can influence PKS activity, (4) to test strain cytotoxicity on human cells and (5) to look for other possible enzymes/proteins of biotechnological interest. Overall design: The dinoflagellate A. carterae was cultured in two conditions, i.e. Nitrogen-starved or -repleted (control) conditions. Cells were harvested at the end of the stationary phase and used for RNA extraction. Triplicate samples of both conditions were sequenced and differential expression analysis was performed. In addition, enzymes with biotechnological interest were identified.