Tiny creatures from University of Wyoming laboratories hitched a ride in a freezer on SpaceX CRS-22 and were delivered to the International Space Station, where they await to show off their strength.
Tardigrades, or “water bears,” have been the subject of study for UW molecular biologist Thomas Boothby and his team.
Starting tomorrow (July 13), the tardigrades will undergo experiments so researchers can better understand changes to their gene expression as they experience stressful environments in space.
“The ultimate goal for the project isn’t just to understand how tardigrades survive in space, but to take that knowledge and apply it to human health,” Boothby says.
By examining the tardigrades, researchers may be able to see if there are certain tricks or certain molecules created to help them survive in space, which can help develop therapies or countermeasures to safeguard astronauts out on long-term space flight missions, Boothby says.
“Being in space can be extremely stressful for organisms, such as humans, that evolved here on Earth,” he says. “When astronauts go up in space, they are confronted with a number of really stressful environmental parameters.”
One is the lack of gravity, which can cause harm to the body, Boothby says.
Additionally, when astronauts are in space, they are no longer in Earth’s protective atmosphere and can be exposed to harmful radiation, he explains.
“Microgravity and radiation make being in space really stressful,” Boothby says.
Previous studies show tardigrades are extremely stress tolerant. They can survive days or weeks without oxygen; being completely dried out; being frozen just above absolute zero (about minus 485 degrees Fahrenheit, when all molecular motion stops); heated to more than 300 degrees Fahrenheit; irradiated several thousand times beyond what a human could withstand; and survive the vacuum of space.
“With this experiment, we are trying to understand how these tiny little animals are able to survive these really stressful conditions of space,” he says. “They seem to do really well. They are still able to reproduce, go about their normal lives and live over multiple generations in space.”
Researchers will look at the changes in gene expression as the tardigrades are exposed to this environment. All living things have DNA, which is like a blueprint that tells their cells what to do. Under different conditions, different parts of the DNA are activated or turned off, Boothby explains.
“Here on Earth, we are going to take basically a snapshot of what the tardigrade DNA usage looks like, what portions of it they are activating to survive on Earth,” he says. “Then, in space, we have two groups. With one group, we will take another snapshot of what they are using right after we thaw them out, so they will only be in space active for a short amount of time. The second group will grow and reproduce on the space station for two months.”
The tardigrades on the space station will be “fixed” using a chemical that will preserve their gene expression profiles, Boothby says.
“Once they are delivered back to us on Earth, we can study the preserved molecules inside the animals to get an idea of what genes they had activated,” he says.
Tardigrades reproduce quickly and will be able to go through four generations during those two months, Boothby says.
“We will look at the fourth generation of these animals grown in space, and take a look at their DNA gene expression and see what they are using,” Boothby says. “Our suspicion is the longer they are in space, the more they will be exposed to microgravity and radiation, and they may need to activate different parts of their DNA to cope with that mounting stress.”