Some of the Acropora hyacinthus corals in the back reef of Ofu Island, American Samoa, are able to thrive in pools that experience daily heat fluctuations of up to 6 °C. To find the molecular basis of this resilience, the researchers compared gene activity in heat-resistant and heat-sensitive A. hyacinthus corals by measuring their transcription — the complement of RNA molecules transcribed from the genes — under different temperatures.
The findings, published in the Proceedings of National Academy of Sciences , reveal of genes that — though present in both populations — are more highly expressed in the temperature-resilient corals. These genes code for antioxidants and other proteins that organisms deploy in response to heat shock.
The study found that the expression of hundreds of the corals’ genes changed in response to their tank water being heated from the control temperature of 29.2 °C to 32.9 °C. But in the heat-resilient corals, around 60 of these genes were already highly expressed at the control temperature.Front-loaded gene expression could be what gives these corals a survival edge in changeable conditions.
- Coral capable of coping with climate change (stuff.co.nz)
- A Glimmer of Hope for Coral Reefs (news.sciencemag.org)
- Heat-resistant corals provide clues to climate change survival (esciencenews.com)
- Why some corals can take the heat (nature.com)
- Coral Fights Back Against Warming Seas (climatedesk.org)