Tardigrades are fascinating organisms, not just because they would likely survive almost any cataclysmic event that’s sure would wipe out all other life forms on Earth, but also because we know so little about them.
On the other hand, researchers from the University of Edinburgh in Scotland and the University of Keio in Japan have dug deeper into tardigrade genetics to learn more about their enigmatic makeup and origins. Specifically, they looked at two different species, including Hypsibius dujardini and Ramazzottius varieornatus.
The findings, published in the journal PLOS Biology, reveal that tardigrades may be more like roundworms than insects, despite how they look.
Image Credit: Tanaka S, Sagara H, Kunieda
They reached this conclusion from the number of HOX genes they found. These genes are responsible for the development of head, limb, and tail development in the embryonic stages, and while most creatures have 10 of these genes, tardigrades only have five.
In this respect, they’ve got a similarity to roundworms, which are said to have the same five HOX genes. Because this is an unusual characteristic, researchers believe that roundworms and tardigrades may be related in some way.
But that’s not all they discovered; it seems the research also paved the way for understanding how survives during long periods of dehydration.
As their cells dry out, the creature begins to produce a type of protein-based ‘bioglass’ that prevents the cells from sustaining any damage during the dry bout. Once water is available again, the cells start to absorb it, replacing the protein that held them over for the time being.
While the concept above isn’t new, this study sought to understand what parts of the creature’s genes were responsible for carrying out the task. The researchers paid close attention to protein activity as they subjected the tardigrades to artificial dehydration conditions.
The results pointed to mechanisms that are responsible for repairing DNA. These same mechanisms appear to be multifunctional, performing more tasks than what meets the eye initially.
“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. It has also been great to work with Kazuharu Arakawa and his Japanese colleagues on this – science is truly global, and together we achieved exciting things,” study co-author Prof. Mark Blaxter said in a statement.
“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.”
We’re only just beginning to understand these microscopic life forms. If we ever want to learn every secret, there’s still a lot more work to be done. Understanding how tardigrades work could help inspire breakthrough technologies to benefit all of humanity.