The Awesome Universe of Tardigrades

By Rafael Pérez

Known as aquatic or marine bears, the tardigrade is a phylum from the kingdom Animalia that has several unique characteristics that make them special. Have you ever wondered what it's like being floating in space without any protection, or living in boiling water? Even more outrageous, being frozen in water for over 30 years? Well, all these questions can be answered by these microscopic organisms, since, as wild as they may seem. These adorable creatures have done all of that and more.

[Source: GettyImages]

Known as the most resistant animal in science, Tardigrades consist of a primary fatlike trunk with 8 minuscule appendages that simulate paws with little 3 to 4 little claws on them. They have a digestive system consisting of a mouth and an anus, as well as intestines; this mouth-like structure looks like a trunk with teeth called a proboscis and two eyelike structures as well as sensory pili all around their body.

Raging around 0.5 to 1.2 millimeters in adults, this phylum consisting of more than 1,000 species has been particularly popular because of its extremophile complex, meaning that it can survive in the craziest environments for humans. Known for being invincible, tardigrades have had different chances to prove their ability to survive. For instance, according to the CBC journal, Japanese scientists were able to revive frozen tardigrades from 1983 in the Antarctic. Researchers found a moss sample in the ice at -20°C and were able to find living tardigrades after unfreezing the moss. But, why are they able to do that? Well, several strategies come into play when talking about their ability to survive in different environments, but one of the most important of them is what is called cryptobiosis. A latent state is used by some cryptobiotic organisms in adverse conditions to protect themselves, slowing their metabolic pathways remarkably and adapting to survive in the environment. In this stage, tardigrades shrink by dehydrating themselves and retracting their paws and trunk — their metabolic rate reduces to almost 0.01% — allowing them to save energy and survive.

At a molecular level, the quirk about tardigrades and their resilience to adverse environments is a protein called DSUP (Damage suppressor) among other factors such as an antioxidant enzyme and a repairing DNA protein. According to a 2020 journal report, this protein has been found effective against X-Ray damage and radiation damage to cells in 40- 50%. And its applications serve due to its flexibility and hardness.

However, their achievements are far from being over, as technology advances, scientists are able to synthesize, study and isolate their genome to analyze particular characteristics. Hence, from the seabed’s vast conditions to the space’s darkness, tardigrades can survive under everything without losing their style.

References

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[10] Qué pasaría si. “¿Qué Pasaría Si Los Tardígrados Fueran Del Tamaño de Un Humano?” YouTube, 16 Mar. 2021, www.youtube.com/watch?v=lEvZaAOz3h4.

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User, Super. “Dsup, una proteína única de tardígrados, protege al DNA de la radiación: ¿Cómo lo hace?” CBGP, 2020, www.cbgp.upm.es/index.php/es/rss-1/14-noticias/1452-dsup-una-proteina-unica-de-tardigrados-protege-al-dna-de-la-radiacion-como-lo-hace#:%7E:text=C%C3%B3mo%20lo%20hace%3F-,Dsup%2C%20una%20prote%C3%ADna%20%C3%BAnica%20de%20tard%C3%ADgrados%2C%20protege%20al%20DNA%20de,atenci%C3%B3n%20en%20biolog%C3%ADa%20y%20biotecnolog%C3%ADa.