|Title||Transcriptional orchestration of the global cellular response of a model pennate diatom to diel light cycling under iron limitation|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Authors||Smith SR, Gillard JTF, Kustka AB, McCrow JP, Badger JH, Zheng H, New AM, Dupont CL, Obata T, Fernie AR, Allen AE|
Author Summary Oceanic diatoms live in constantly fluctuating environments to which they must adapt in order to survive. During sunlit hours, photosynthesis occurs allowing diatoms to store energy used at night to sustain energy demands. Cellular and molecular mechanisms for regulation of phytoplankton growth are important to understand because of their environmental roles at the base of food webs and in regulating carbon flux out of the atmosphere. In ocean ecosystems, the availability of iron (Fe) commonly limits phytoplankton growth and diatoms typically outcompete other phytoplankton when Fe is added, indicating they have adaptations allowing them to both survive at low Fe and rapidly respond to Fe additions. These adaptations may be unique depending on isolation from coastal or oceanic locations. To identify adaptive strategies, we characterized the response of a model diatom, Phaeodactylum tricornutum, to limiting Fe conditions over day:night cycles using a combination of gene expression analyses, metabolite, and physiology measurements. Major coordinated shifts in metabolism and growth were documented over diel cycles, with peak expression of low Fe expressed genes in the dark phase. Diatoms respond to limiting Fe by increasing Fe acquisition, while decreasing growth rate through slowed cell cycle progression, reduced energy acquisition, and subtle metabolic remodeling.
|Short Title||PLoS Genet.|