How corals adapt to day and night

Sep 12, 2008
Skeletal calice of the symbiotic coral, Stylophora pistillata. Credit: Didier Zoccola, Centre Scientifique de Monaco

Researchers have uncovered a gene in corals that responds to day/night cycles, which provides some tantalizing clues into how symbiotic corals work together with their plankton partners.

Corals are fascinating animals that form the largest biological constructions in the world, sprawling coral reefs that cover less than 0.2 % of the seafloor yet provide habitats for more than 30% of marine life. In shallow waters that don't have abundant food, corals have developed a close relationship with small photosynthetic critters called dinoflagellates.

The dinoflagellates use sunlight to produce energy for the coral, which in turn use that energy to construct mineralized skeletons for protection. The mineral production, known as coral calcification, is closely tied with the day/night cycle, though the molecular mechanism behind this synchronization is mysterious.

Aurelie Moya and colleagues have now characterized the first coral gene that responds to the light cycle; this gene, called STPCA, makes an enzyme that converts carbon dioxide to bicarbonate (baking soda) and is twice as active at night compared to daytime. The researchers found that the enzyme concentrates in the watery layer right under the calcified skeleton, which combined with studies showing that STPCA inhibitors lower calcification rates, confirms a direct role for STPCA in this process.

Moya and colleagues propose that STPCA becomes more active at night to cope with acid buildup. The calcification process requires many hydrogen atoms, which during the day can be removed by photosynthesis; at night, however, hydrogen accumulates which increases the acidity of the coral, and therefore STPCA creates extra bicarbonate as a buffer to prevent acid damage.

Citation: "Carbonic Anhydrase in the Scleractinian Coral Stylophora pistillata" by Aurélie Moya, Sylvie Tambutté, Anthony Bertucci, Eric Tambutté, Séverine Lotto, Daniela Vullo, Claudiu T. Supuran, Denis Allemand, and Didier Zoccola

Article URL: www.jbc.org/cgi/content/full/283/37/25475

Source: American Society for Biochemistry and Molecular Biology

Explore further: Bulletproof nuclei? Stem cells exhibit unusual absorption property

add to favorites email to friend print save as pdf

Related Stories

Hackathon team's GoogolPlex gives Siri extra powers

25 minutes ago

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Record labels sue Pandora over older songs

35 minutes ago

Major record labels are suing Internet radio giant Pandora for copyright infringement for using songs recorded before 1972 without paying license fees.

Recommended for you

Plants with dormant seeds give rise to more species

Apr 18, 2014

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Researchers successfully clone adult human stem cells

Apr 18, 2014

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

User comments : 0

More news stories

Biologists help solve fungi mysteries

(Phys.org) —A new genetic analysis revealing the previously unknown biodiversity and distribution of thousands of fungi in North America might also reveal a previously underappreciated contributor to climate ...

Making graphene in your kitchen

Graphene has been touted as a wonder material—the world's thinnest substance, but super-strong. Now scientists say it is so easy to make you could produce some in your kitchen.