title: Enhancement of Non-photochemical Quenching as an Adaptive Strategy under Phosphorus Deprivation in the DinoflagellateKarlodinium veneficum.
abstract: Intensified water column stratification due to global warming has the potential to decrease nutrient availability while increasing excess light for the photosynthesis of phytoplankton in the euphotic zone, which together will increase the need for photoprotective strategies such as non-photochemical quenching (NPQ). We investigated whether NPQ is enhanced and how it is regulated molecularly under phosphorus (P) deprivation in the dinoflagellateKarlodinium veneficum. We grewK. veneficumunder P-replete and P-depleted conditions, monitored their growth rates and chlorophyll fluorescence, and conducted gene expression and comparative proteomic analyses. The results were used to characterize NPQ modulation and associated gene expression dynamics under P deprivation. We found that NPQ inK. veneficumwas elevated significantly under P deprivation. Accordingly, the abundances of three light-harvesting complex stress-related proteins increased under P-depleted condition. Besides, many proteins related to genetic information flow were down-regulated while many proteins related to energy production and conversion were up-regulated under P deprivation. Taken together, our results indicate thatK. veneficumcells respond to P deprivation by reconfiguring the metabolic landscape and up-tuning NPQ to increase the capacity to dissipate excess light energy and maintain the fluency of energy flow, which provides a new perspective about what adaptive strategy dinoflagellates have evolved to cope with P deprivation.
authors.affiliation: State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Xiamen City Key Laboratory of Urban Sea Ecological Conservation and Restoration, Xiamen University Xiamen, China.
authors.forename: Yudong
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Department of Marine Sciences, University of Connecticut, Groton CT, USA.
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Marine Environmental Science and Marine Biodiversity and Xiamen City Key Laboratory of Urban Sea Ecological Conservation and Restoration, Xiamen UniversityXiamen, China; Department of Marine Sciences, University of Connecticut, GrotonCT, USA.
authors.forename: Senjie
authors.initials: S
authors.lastname: Lin
keywords: dinoflagellates; energy flow; metabolic machinery reconfiguration; non-photochemical quenching; phosphorus deprivation