Molecular Response of the Brain to Cross-Generational Warming in a Coral Reef Fish

Ocean warming is a threat to marine biodiversity, as it can push species beyond their physiological limits. Detrimental effects occur when poikilotherms are exposed conditions thermal optima. However, acclamatory mechanisms, such plasticity, may enable compensation of detrimental if experienced during development or across generations. Studies evaluating the molecular responses fishes have mostly focused on liver, muscle, and gonads, little known about other vital organs, including brain. This study evaluated transcriptional program brain in coral reef fish Acanthochromis polyacanthus , two different scenarios: +1.5°C +3.0°C, successive Fish were these both developmental (F1 F2) transgenerational settings (F2 only), well treatment with step-wise between The largest differences gene expression individuals first second generation, pattern that was corroborated by pairwise comparisons Control F1 F2 (7,500 DEGs) fish. large difference could be associated parental effects, parents generation collected from wild, whereas reared captivity. A general response observed at temperatures treatments included protein folding, oxygen transport (i.e., myoglobin), apoptosis cell death, modification cellular structure, mitochondrial activity, immunity changes circadian regulation. Treatments highest temperature showed reduction synaptic activity neurotransmission, which matches previous behavioral observations fishes. Transgenerational +3.0°C significant activation pls3 for neuro-muscular junctions under heat-stress. samples an intermediate response, few differentially expressed genes compared groups (except +1.5°C). In combination studies liver expression, this indicates produces signature stress A. influenced intensity duration exposure.