Molecular basis of parental contributions to the behavioural tolerance of elevated pCO2 in a coral reef fish

• Published in: Proceedings of the Royal Society B: Biological Sciences
• Main Authors: Marshall, Danielle A, Schunter, Celia, Welch, Megan J., Munday, Philip, Ravasi, Timothy
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Royal Society Publishing 2021
• Subjects: genetic variance; climate change; ocean acidification; phenotypic variation; transcriptome; parental effects; Ocean acidification
• Online Access: https://hdl.handle.net/1969.6/90402; https://doi.org/10.1098/rspb.2021.1931

Knowledge of adaptive potential is crucial to predicting the impacts of ocean acidification (OA) on marine organisms. In the spiny damselfish, Acanthochromis polyacanthus, individual variation in behavioural tolerance to elevated pCO2 has been observed and is associated with offspring gene expression patterns in the brain. However, the maternal and paternal contributions of this variation are unknown. To investigate parental influence of behavioural pCO2 tolerance, we crossed pCO2-tolerant fathers with pCO2-sensitive mothers and vice versa, reared their offspring at control and elevated pCO2 levels, and compared the juveniles' brain transcriptional programme. We identified a large influence of parental phenotype on expression patterns of offspring, irrespective of environmental conditions. Circadian rhythm genes, associated with a tolerant parental phenotype, were uniquely expressed in tolerant mother offspring, while tolerant fathers had a greater role in expression of genes associated with histone binding. Expression changes in genes associated with neural plasticity were identified in both offspring types: the maternal line had a greater effect on genes related to neuron growth while paternal influence impacted the expression of synaptic development genes. Our results confirm cellular mechanisms involved in responses to varying lengths of OA exposure, while highlighting the parental phenotype's influence on offspring molecular phenotype. The authors acknowledge the support of the Office of Competitive Research Funds OSR-2015-CRG4–2541 from the King Abdullah University of Science and Technology (T.R. and P.L.M.), the Australian Research Council (ARC) and the ARC Centre of Excellence for Coral Reef Studies (P.L.M).