The nearly invincible tardigrades have a secret chemical weapon
Scientists may have discovered one of the many mysteries surrounding everyone’s favorite microscopic survivor: the tardigrade. In new research, the team appears to have uncovered a key mechanism these tiny creatures use to withstand extreme conditions that would kill almost any other animal.
Tardigrades They are a group of eight-legged invertebrates (their closest living relatives are either arthropods or nematodes; further evidence Currently supported the last one). Their adorable appearance has earned them the nicknames “water bears” or “moss pigs.” But it’s their uncanny ability to survive anything thrown at them that makes them so popular. Tardigrades can live in some of the harshest places on Earth (and even some of the most inhospitable places on Earth). Out of it) And if times get too tough, they can also enter a period of death-like dormancy.
This ability is widely known as cryptobiosis, and the most famous state of rest that tardigrades can achieve is known as tun. The tardigrade will suck out its eight limbs, curl up into a ball, and exhaust almost all of its internal water supply. In this state of dehydration, some tardigrades were able to withstand extreme heat, temperatures near absolute zero, and exposure to salt levels that would kill almost everything else in the world. Depending on the species and their environment, tardigrades can remain hibernating for decades or even longer, until environmental conditions improve.
Over the years, scientists have learned more about the specific tricks that tardigrades use to achieve and maintain tuning. But in a new paper published In PLOS One, a team of researchers says they have discovered at least one of the chemical switches that allow tardigrades to undergo seizures in the first place.
In a series of experiments, the team found evidence that reactive oxygen species (ROS) appear to play a key role in mediating the tuning process. ROS are a group of unstable oxygen-containing chemicals that are produced by the normal breakdown of other molecules in the body. Although the accumulation of some types of ROS may contribute to health problems such as cancer, these molecules also have important biological functions, such as signaling or stimulating other cellular processes.
The researchers found that in tardigrades, ROS appear to signal the oxidation of the amino acid cysteine, which in turn appears to be crucial for ton formation. When the team found ways to turn off the ability to oxidize cysteine in young test subjects, the tardigrades lost their ability to control as before, further supporting their hypothesis.
The results are based on studying only one species of tardigrade (Hypsibius model). Even if this research bears further scrutiny, scientists know they have not solved every aspect of tardigrade survival. Not all known species are susceptible to tardigrades, and there are other strategies used by tardigrades to tolerate poor living conditions. But this research should provide new ways to explore these amazing animals.
“We have opened up a huge repertoire of experiments that we can now pursue,” says study author Leslie Hicks, a chemist at the University of North Carolina at Chapel Hill. Tell American Scientific.
(Tags for translation) Environment