As our listeners know, we're big fans of a little creature called Tardigrades, also known as water bears. They may be only half a millimeter long, but they can live through astonishing conditions such as -458 degrees (fahrenheit) or as high as 300 degrees! In early fall 2016, researchers in Japan published a new analysis of the entire genome of this fascinating animal. link
One of their best survival tricks is called "cryptobiosis" which basically an extreme form of hibernation where ALL metabolic functions stop. This suspends the creature between life and death, thus allowing it to survive almost anything. Even more impressive, it can even be dried out to roughly 3% of its normal water content and come back to life with a simple spalsh of water. But how is this possible?
Geneticist Takekazu Kunieda, along with his colleagues, from the University of Tokyo found some of the genetic tricks that have helped the tardigrades to survive in extreme environments. However, the process of this research was a bit complicated.
First, because it is easier to study these processes when housed within mammalian cells. So, in order to create a successful study the researchers cultured humans cells to produce bits of the tardigrade genome. From this space the cells of the tardigrade could be manipulated to figure out exactly which genes give these creatures their incredible resistance to all sorts of environments.
In living creatures, dehydration can wreak havoc among cells and even rip apart DNA. For example, Humans are made of, depending on age/gender, about 55-65% water. Imagine that shrinking to 3-10%...needless to say, it would be drastic and likely impossible. However, unlike humans tardigrades have a protein called Dsup. Dsup has the ability to hold DNA together, even under the stress of drying out.
Additionally, when Kunieda and his team pinpointed this impressive protein, they also found that it protects the DNA from radiation. Kunieda says, "Tolerance against X-ray is thought to be a side-product of [the] animal’s adaption to severe dehydration,"
One of the most important takeaways is that the researchers found that human cells, aided by Dsup, reduced x-ray damage by up to 40%. The future of medicine may heavily affected by this seemingly minuscule creature!
The picture above comes from Flickr User Eden, Janine and Jim and is licensed under Creative Commons.