Cui Yudong, Zhang Huan, Lin Senjie
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.
Department of Marine Sciences, University of Connecticut, Groton CT, USA.
Front Microbiol. 2017 Mar 15;8:404. doi: 10.3389/fmicb.2017.00404. eCollection 2017.
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 dinoflagellate . We grew under 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 in was 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 that cells 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.
全球变暖导致的水柱分层加剧有可能降低营养物质的可用性，同时增加透光层中浮游植物光合作用的过量光照，这将共同增加对诸如非光化学猝灭（NPQ）等光保护策略的需求。我们研究了在磷（P）缺乏的情况下，甲藻中的NPQ是否增强以及其分子调控方式。我们在磷充足和磷缺乏的条件下培养甲藻，监测它们的生长速率和叶绿素荧光，并进行基因表达和比较蛋白质组学分析。结果用于表征磷缺乏条件下NPQ的调节及相关基因表达动态。我们发现，在磷缺乏条件下，甲藻中的NPQ显著升高。相应地，在磷缺乏条件下，三种光捕获复合体应激相关蛋白的丰度增加。此外，在磷缺乏条件下，许多与遗传信息传递相关的蛋白质下调，而许多与能量产生和转换相关的蛋白质上调。综上所述，我们的结果表明，甲藻细胞通过重新配置代谢格局和上调NPQ来应对磷缺乏，以增加消散过量光能的能力并维持能量流动的顺畅，这为甲藻进化出何种适应策略来应对磷缺乏提供了新的视角。
