Molecular underpinnings underlying behaviors changes in the brain of juvenile common carp (Cyrinus carpio) in response to warming

Global warming is increasing interest in how aquatic animals can adjust their physiological performance and cope with temperature changes. Therefore, understanding the behavioral changes and molecular underpinnings in fish under warming is crucial for both the individual and groups survival. This could provide experimental evidence and resource for evaluating the impact of global warming. Three genetic families of common carp (Cyprinus carpio) were generated. These juveniles were constructed short-term (4 days) and long-term (30 days) warming groups to investigate the effects of warming on behavioral responses and to elucidate the potential underlying mechanisms of warming-driven behavior. Behavioral tests were used to explore the effects of short- and long-term exposure to warming on the swimming behavior of C. carpio. Brain transcriptome combined with measurement of nervous system activity was used to further investigated the comprehensive neuromolecular mechanisms under warming. Long-term warming groups had a more significant impact on the decline of swimming behavior in juvenile C. carpio. Furthermore, brain comparative transcriptomic analysis combined with measurement of nervous system activity revealed that genes involved in cytoskeletal organization, mitochondrial regulation, and energy metabolism are major regulators of behavior in the juvenile under warming. Importantly, especially in the long-term warming groups, enrichment analysis of associated gene expression suggested functional alterations of synaptic transmission and signal transduction leading to swimming function impairment in the central nervous system, as revealed by behavioral tests. Our study provides evidence of the neurogenomic mechanism underlying the decreased swimming activity in juvenile C. carpio under warming. These findings have important implications for understanding the impacts of climate change on aquatic ecosystems and the organisms that inhabit them.