Coral reefs are greatly impacted by climate change: rising temperatures cause coral bleaching and outbreaks of infectious diseases become increasingly common. However, reef-building corals may have found a way to adapt and survive, thanks to a method of epigenetic inheritance discovered by an international team of researchers.
Corals provide habitats for thousands of marine species, protect shorelines and support human livelihoods. However, corals are experiencing severe global decline, and the rapid rate of climate change threatens to overwhelm the capacity for adaptation by genetic means alone.
Researchers from NYU Abu Dhabi, King Abdullah University of Science and Technology and the University of Eastern Finland discovered that reef-building corals can pass epigenetic adaptations to their offspring. An epigenetic adaptation is an external modification to the DNA that can turn genes “on” or “off” without altering the actual genome. The discovery, reported in Nature Climate Change, can open up new avenues for combating the loss of coral reefs. According to the researchers, the findings suggests that coral colonies and larvae that have already epigenetically adapted to warmer temperatures can be used to repopulate dying reefs.
Early Stage Researcher Craig Michell from the University of Eastern Finland Department of Environmental and Biological Sciences was part of the team. His role in the study was to perform genome and RNA sequencing.
“This research shows that as corals adapt to new environments these epigenetic changes are able to be passed on to the next generation, providing the next generation better chances of survival in the changing environment. Understanding this mechanism may help with future breeding programmes for coral species,” Michell says.
The researchers collected adult brain corals (Platygyra daedalea) from reef sites in Abu Dhabi in the southern Arabian Gulf and in Fujairah in the Sea of Oman, and analysed the corals’ genomes, sperm and larvae. The Abu Dhabi corals had been exposed to extreme temperatures and salinity, while the Fujairah ones lived in more moderate conditions.
“We found different patterns of methylation in the genomes of the corals from Fujairah and Abu Dhabi, such as hyper-methylation of genes related to stress responses allowing them to cope with their harsher environment,” Michell says.
For further information, please contact:
Early Stage Researcher Craig Michell, email: craig.michell(at)uef.fi
Research article:
Liew, Y.J., Howells, E.J., Wang, X. et al. Intergenerational epigenetic inheritance in reef-building corals. Nat. Clim. Chang. (2020). https://doi.org/10.1038/s41558-019-0687-2
In the photo: Platygyra daedalea.