Genes associated with stress tolerance in corals have fewer epigenetic markers, enabling a rapid response to environmental change. In six species of coral, the team from the University of Washington found DNA methylation, a common epigenetic molecular marker, differed between different genetic regions, and was extremely low in genes relating to stress tolerance. Epigenetics could play a key role in determining how corals cope with climate change.
A study published this week in Molecular Ecology shows that methylated DNA – an epigenetic marker passed from parent to offspring that influences how and when genes are expressed – may be important in regulating how corals cope with environmental change.
The team studied six species of reef-building coral, Acropora hyacinthus, Acropora millepora, Acropora palmata, Pocillopora damicornis, Porites astreoides, Stylophora pistillata and Stylophora pistillata, and assembled a list of the genes expressed at different life stages of the coral. All corals showed relatively low levels of methylation across their genomes, indicating a weaker influence of epigenetics and greater responsiveness, with a few hotspots of hypermethylation. These regions tended to include “housekeeping genes”, which are expressed relatively consistently and evolve extremely slowly.
In three Acropora species, known as Staghorn Coral, genes associated with tolerance to extreme temperatures and ocean acidification tended to lack methylation, enabling them to be rapidly expressed when conditions change.
Want to Know More?
- Diamond and Roberts (2015)Germline DNA methylation in reef corals: patterns and potential roles in response to environmental change Molecular Ecology
- Duncan, Gluckman and Dearden (2014) Epigenetics, plasticity, and evolution: How do we link epigenetic change to phenotype? Journal of Experimental Zoology
- Bayer et al (2012) Symbiodinium Transcriptomes: Genome Insights into the Dinoflagellate Symbionts of Reef-Building Corals PLOS ONE
- Barshis et al (2012) Genomic basis for coral resilience to climate change PNAS