Cross-talk between tissues is critical for intergenerational acclimation to environmental change

An organism’s reaction to environmental changes is mediated by coordinated responses of multiple tissues. Additionally, parental priming may increase offsprings’ acclimation potential to changing environmental conditions. As the effects of human-induced climate change, such as ocean acidification (OA), continue to intensify it is critical to assess the acclimation potential of species at the whole organismal scale. For this we need to understand the cross-talk between tissues in regulating and responding to pH changes. Here by using a multi-tissue approach we determine the influence of 1) variation in parental behavioural tolerance and 2) parental environment, on molecular responses of their offspring in a coral reef fish. The gills and liver showed the highest transcriptional response to OA conditions in juvenile fish regardless of the parental environment, while the brain and liver showed the greatest signal of intergenerational acclimation. Key functional pathways that were altered in the brain upon within-generational CO 2 exposure were restored to control levels when parents were exposed to OA conditions. Furthermore, the expression of a new complement of genes involved in key functions was altered in the offspring only when parents were previously exposed to OA conditions. Therefore, previous parental conditioning to OA can reprogram tissue transcriptomic profiles of the offspring enabling them to better cope in an environment with elevated CO 2 levels. Overall, our results reveal tissue-specific transcriptional changes underlying intergenerational plastic responses to elevated CO 2 exposure and highlight the integration of these changes in promoting organismal acclimation to OA.