Originally, it was thought that the water bear employed a sugar called trehalose to shield its cells from damage. Brine shrimp (sea monkeys) and nematode worms use this sugar to protect against desiccation, through a process called anhydrobiosis. Those organisms produce enough of the sugar to make it 20% of their body weight.
Not the water bear. Trehalose only takes up about 2% of its entire system, when it's in stasis. Though employing a sugar to preserve one's body sounds strange, the newly discovered process that the water bear goes through is even more bizarre. It turns itself into glass.
In this study, tardigrades were placed into a drying-out chamber, which mimicked conditions the organisms would encounter in a disappearing pond. As the water bears underwent anhydrobiosis, scientists examined what genes were activated. These genes produced a certain protein, which they named tardigrade-specific intrinsically disordered proteins (TDPs).
When desiccation begins and TDP is activated, it engages a process known as vitrification. Boothby said, “The glass is coating the molecules inside of the tardigrade cells, keeping them intact." From there, it goes into a form of stasis until it detects water. When that occurs, the protein is dissolved into the liquid and the tardigrade is revived.
https://bigthink.com/philip-perry/scientists-finally-figure-out-why-the-water-bear-is-nearly-unstoppable
That's incredibly weird!
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