Researchers discover new clues to how tardigrades can survive intense radiation

University of North Carolina at Chapel Hill researchers have discovered that tardigrades – microscopic animals famed for surviving harsh extremes – have an unusual response to radiation.

Radiation has long been known to damage DNA, and in humans, DNA damage from excessive radiation exposure can lead to diseases. But the tardigrades have an unexpected way to correct the damage. "What we saw surprised us," said Bob Goldstein. "The tardigrades are doing something we hadn't expected."

Courtney Clark-Hachtel, a former postdoctoral scholar in the lab, joined the group to examine how tardigrades can survive intense radiation. She found that a species of tardigrade is not immune to DNA damage – irradiation does damage their DNA – but the tardigrades can repair extensive damage. Clark-Hachtel and Goldstein were surprised to find that tardigrades can increase the volume of production from DNA repair genes. Unlike humans, tardigrades can ramp up the level of DNA repair genes' products to such an extreme extent that they become some of the most abundant gene products in animals.

"These animals are mounting an incredible response to radiation, and that seems to be a secret to their extreme survival abilities," said Clark-Hachtel. "What we are learning about how tardigrades overcome radiation stress can lead to new ideas about how we might try to protect other animals and microorganisms from damaging radiation."

Image source: Kiosya et al. (2021), Evolutionary Systematics, CC BY-SA 4.0.