How Can Water Bears Survive Desiccation?

BEACON TRANSCRIPT – Water bears are microscopic animals that have always baffled scientists with their incredible ability to resist conditions that would kill other living creatures. Now, they have discovered what helps them survive in one of the harshest environments on Earth.

Water bears, also known as tardigrades, are fascinating because they can live in the most extreme of conditions found on Earth. For instance, one of their most mind-blowing traits is the fact that they can survive even after being completely dried out for a decade. This is, probably, the most important feature of tardigrades that kept scientists wondering for centuries.

What is their coping mechanism?

However, a team of scientists claims to have discovered the secret. In a study published in the journal Molecular Cell, they identified some proteins that could be preventing the tiny water bears from dehydrating. These are called tardigrade-specific intrinsically disordered proteins (TDPs).

Tardigrades are not the only organisms that can survive drying. Yeasts or brine shrimps have a sugar called trehelose which helps them cope with extreme dryness, but previous studies discovered that water bears do not have trehelose present in their bodies. They do not have the gene that helps them produce the enzyme which makes trehelose.

Thus, researchers started looking for other mechanisms which prevented dying from desiccation. They isolated several proteins that could help in the process. These include eat-shock proteins, antioxidant enzymes, and, of course, intrinsically disordered proteins. Then, they started placing tardigrades in different situations to see how their genes reacted.

They studied water bears’ genes

They studied the water bears while being unstressed, dried out, and frozen. When they were dried out, they analyzed their genome and looked what genes were expressed at a high level. Thus, they found the genes which were responsible with making the tardigrade-specific intrinsically disordered proteins.

Scientists found these genes highly activated while the water bears were dried out in three different species, thus confirming the importance of the protein for tardigrades. Then, they showed how important the proteins were by introducing them in other organisms, such as bacteria, and observing that they could protect them from desiccation, too.

Researchers aim to continue their study of intrinsically disordered proteins, as they can have appliances in different fields, too, apart from protecting living organisms from desiccation. By using them, scientists can protect crops from droughts and better preserve drugs which need to be frozen for storage.
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