Corals in the Red Sea: Imaging Tool Colors?

Down in the dark, distinctly non-red depths of the Red Sea, glowing, rainbow-colored corals have been discovered. Such colorful pigments could prove useful for medicine, as scientists from the University of Southampton, Tel Aviv University, and the Interuniversity Institute for Marine Sciences (Israel), with an international team of researchers, recently reported in the research journal PLOS ONE. 

The hope is that the corals can provide pigments to be developed into new imaging tools for medical applications, researchers said in their report.

Scientists studied corals at depths of more than 164 feet, finding that many of them glow green, yellow, red, and other fluorescent colors. Conversely, the coral in shallow water in the same reef contained only green fluorescent pigments, as scientists reported in a release. 

The ultra-bright pigments are proteins, says Jörg Wiedenmann, Professor of Biological Oceanography and Head of the University of Southampton's Coral Reef Laboratory, according to a press release. "Their optical properties potentially make them important tools for biomedical imaging applications, as their fluorescent glow can be used to highlight living cells or cellular structures of interest under the microscope. They could also be applied to track cancer cells or as tools to screen for new drugs."

Because these corals are beyond the depth limits of standard Scuba diving techniques, these mesophotic reefs are less well studied, said Gal Eyal, PhD candidate at the IUI. The scientists were able to study them because of advances in technical diving, he noted in a release.

"We found...that some of the pigments of these corals require violet light to switch from their nascent green color to the red hue of the mature pigment. This is a particularly interesting property to develop markers for advanced microscopic imaging applications," said Dr Cecilia D'Angelo, Senior Research Fellow at Southampton, who has studied corals commonly found in mesophotic depths in the experimental aquarium of the University's Coral Reef Laboratory, according to a release. 

The team is now exploring which other biological functions these fluorescent pigments may fulfill, they said in a release. 

Learn more about mesophotic reefs here.