Tardigrade’s DNA reveals water bears’ secrets

July 27 (UPI) — New DNA analysis has unlocked several secrets of the water bear, known to scientists as tardigrades.

The fresh tardigrade genome sequence offers new clues to the water bear’s hardiness, as well as the identities of its closest relatives.

Water bears are possibly the most resilient organism on the planet. The microscopic creatures can be dehydrated and then resuscitated years later with a drop of water. They can also be frozen and thawed, exposed to radiation and sent to space and back, each time springing back to life.

Previous research suggests tardigrades have picked a smorgasbord of foreign gene sequences from other animals and bacteria, populating their genome with the DNA necessary to withstand the harshest of conditions.

But the latest DNA analysis suggests the organism’s genome is rather ho hum. Its genome is normal. Foreign DNA segments can be explained by contamination, a team of scientists from Scotland and Japan argue.

Previous analysis has shown tardigrades to be more closely related to arthropods, the group that includes insects and spiders, and nematodes, or roundworms. The latest analysis suggests water bears are closer to nematodes than arthropods on the family tree.

Scientists were also able to identify the tardigrade genes responsible for producing the proteins that protect water bears from desiccation and radiation.

The team of researchers published their latest findings this week in the journal PLOS One.

“I have been fascinated by these tiny, endearing animals for two decades. It is wonderful to finally have their true genomes, and to begin to understand them,” Mark Blaxter, a professor at the University of Edinburgh, said in a news release. “This is just the start — with the DNA blueprint we can now find out how tardigrades resist extremes, and perhaps use their special proteins in biotechnology and medical applications.”