Rare Marine Worm Glows Under X‑Rays, Revealing Hidden Biology

Researchers at the University of Tokyo have uncovered a surprising property in a little-known deep‑sea polychaete worm. When exposed to X‑ray radiation, the marine worm exhibits a faint glow caused by previously undocumented fluorescent proteins. The discovery, published last week in Journal of Experimental Marine Biology and Ecology, suggests these proteins may help the organism cope with naturally occurring radiation in its environment.

The team collected the worms from depths of 800 to 1,200 meters in the Pacific Ocean. In laboratory experiments, specimens emitted visible light when exposed to X‑ray sources, with intensity levels that varied by depth of collection. Molecular analysis identified two novel proteins responsible for the effect, both of which activate under ionizing radiation and emit greenish fluorescence. These proteins differ fundamentally from the GFP-related proteins widely used in biotechnology.

Scientists think the glow might serve as a protective mechanism, helping the worm detect or dissipate radiation before cellular damage occurs. Such a biological response could be vital for survival in environments with elevated radioactive materials, such as hydrothermal vents or uranium‑rich sediments.

The implications extend beyond marine biology. These new proteins may have biotechnological applications in radiation detection or imaging. Unlike conventional fluorophores, they activate in direct response to radiation and could be engineered into sensors for medical or environmental monitoring.

The researchers are currently working to sequence the genes responsible and express the proteins in bacterial systems. Their goal is to explore potential uses in wearable radiation monitors or subterranean bio‑calculators that alert to background radiation levels.

This discovery highlights how marine organisms continue to surprise us with adaptations that defy conventional expectations—and opens the door to innovative tools inspired by life in the deep.

Sources

https://phys.org/news/2025-06-marine-worm-x-ray-fluorescent-proteins.html

https://www.journals.elsevier.com/journal-of-experimental-marine-biology-and-ecology