Transcriptional responses and nutrient cycling dynamics in sea anemone Exaiptasia pallida under thermal stress and nitrogen pollution

Climate change-induced temperature rise causes a significant threat to marine organisms, including the cnidarians such as corals and sea anemones. Synchronously, many coastal environments are experiencing increased nutrient pollution causing eutrophication. Existing research primarily focuses on the isolated effects of thermal stress or exogenous nitrogen on marine animals. This study utilised the sea anemone Exaiptasia pallida as a model to investigate how cnidarians are influenced under the combined stressors of temperature and exogenous nitrogen. We revealed that both stress-related chaperone genes, such as those regulating heat shock proteins and redox enzymes, and genes involved in nitrogen and ammonia metabolic pathways were differentially regulated. In addition, the rate of nitrate consumption in sea anemone was elevated under higher temperatures, verifying the hypothesis that an increase in temperature will enhance consumption of the excess nitrate under eutrophic conditions. This study provides new insights into the combined effects of increased temperature and eutrophication for cnidarians.