Emiliania huxleyi CCMP371 Transcriptome project. Emiliania huxleyi CCMP371

Emiliania huxleyi is the most abundant coccolithophore in the world’s ocean, and plays a major role in the global carbon cycle by regulating the exchange of CO2 across the ocean-atmosphere interface through photosynthesis and calcium carbonate precipitation. In this study, we maintained E. huxleyi in continuous culture for at least 200 generations under diurnal light, two different pCO2 levels and two nitrogen sources (ammonium/nitrate mix and nitrate alone) and showed that assimilation of nitrogen as ammonium depresses calcification at both ambient and elevated pCO2, alters coccolith size and shape, and increases primary production (please see DOI: 10.1111/j.1365-2486.2011.02575.x for detailed culturing condition). Deep RNA sequencing analysis allowed us to observe dynamic diurnal changes in transcripts related to photosynthesis, cell cycle, nitrogen assimilation metabolism and possibly calcification. This study provides an insight into the transcriptomic response of E. huxleyi to different environmental cues and together with physiological measurement shade light on the complex and flexible response of this organism to changes in its environment.