GSE66997
Global transcriptome responses of a marine diatom to phosphate fluctuations provides insights into its ecological success
Phosphate (Pi) is an essential element to all living cells yet fluctuations in Pi concentrations are recurrent in the marine environment. Diatoms are amongst the most successful phytoplankton clade living in the world's oceans adapting to and surviving long periods of sub-optimal conditions and resuming growth as soon as nutrient concentrations permit. The knowledge of the molecular underpinnings of diatom ecological success is, however, still very incomplete. Using high-throughput RNA sequencing we have identified the dynamics of the model diatom Phaeodactylum tricornutum global transcriptome in response to Pi fluctuations. We report genes encoding previously unidentified putative Pi transporters that, together with the alkaline phosphatases genes highly expressed under Pi depletion, are probably accountable for a very efficient Pi scavenging system. Our data also reveal the complexity of the P. tricornutum responsive sensory and signaling system that combines bacterial two-component systems with more complex pathways reminiscent of metazoans. This intricate set of membrane receptors and signal-transduction related proteins is likely responsible for the detection of environmental nutrient fluctuations, triggering a multitude of signaling cascades leading to gene regulatory events that define new adaptive physiological states. This together with the novel detection of a multitude of long non-coding intergenic RNAs specifically expressed under Pi stress, begins to provide insights into the complex molecular regulatory program involved in the resilience and ecological success of diatoms. Overall design: Examination of Pi-responsive transcriptoms in diatoms.