Uncovering the molecular and epigenetic mechanisms enabling corals to cope with climate change

At least 500 million people and >25% of all marine species directly rely on coral reefs – an ecosystem valued at $9.9 trillion annually, but one that is predicted to decline 70-90% by 2050 due to global climate threats. In addition to reef adaptation strategies, targeted approaches to enhance coral acclimation are critical for the persistence of reefs under future climate change scenarios. Yet, the molecular mechanisms underpinning acclimation in corals remain unclear, hindering the development of new restoration technologies. Environmentally sensitive epigenetic modifications, such as DNA methylation, are important molecular mediators of acclimation in many species. However, in corals, it remains unclear how DNA methylation is linked to climate resilience. With the support of the Marie Skłodowska-Curie Actions programme, EPICORAL will test a new, integrative and mechanistic hypothesis: that DNA methylation mediates coral climate resilience by maintaining transcriptional fidelity under stressful conditions. EPICORAL will take a multidisciplinary approach, building on complementary areas of expertise in marine ecology, genomics, epigenetics and transcriptomics to leverage a unique, in-situ experiment in a semi enclosed lagoon (where corals are long-term acclimatized to acidification, deoxygenation and thermal stress), and at a nearby control reef (where conditions are more benign). EPICORAL aims to elucidate previously unexplained scientific findings through high level training and knowledge transfer. By uncovering the role DNA methylation plays in coral climate resilience, EPICORAL will help to validate reef restoration approaches relying on the concept of “epigenetic conditioning” and provide early indications of coral stress-exposure through the development of “epigenetic biomarkers”.