Species that overreact to distress signals from algae more likely to succumb to warming
If the symbiotic algae living inside some corals jumped off a bridge, the corals would follow. But other corals are able to resist such lemminglike behavior, and now scientists think a suicide protein may explain the difference between the two groups.
Some corals overreact to distress signals sent by resident algae when waters warm, researchers in New Jersey and Israel report online June 2 in the Proceedings of the National Academy of Sciences. The overreactors ramp up production of an executioner protein called caspase and eventually commit cellular suicide. Corals that survive warming start out with high levels of caspase but then quickly decrease the amount of the protein, the researchers found.
The study “adds critical data to help figure out how coral bleaching happens,” says Stephen Palumbi, a marine population biologist at Stanford University who was not involved in the research. Corals bleach when their algae become stressed by warm