02/25/2025 | News release | Distributed by Public on 02/25/2025 11:57
Tardigrades, also known as "water bears" or "moss piglets," are ubiquitous, tiny creatures that have huge potential for groundbreaking discoveries.
These microscopic creatures have already been discovered to be able to handle up to 1,000 times the amount of radiation humans can withstand, as well as survive in extremely hot or cold environments.
Courtney Clark-Hachtel, assistant professor of biology, along with biology student and research assistant Kayla Barrett, are seeking to build upon discoveries about tardigrades radiation resistance.
Clark-Hachtel's research, conducted in UNC-Chapel Hill researcher Bob Goldstein's lab, revealed tardigrades' DNA is damaged by radiation the same way a human's would be, but they can repair it at a remarkable rate through their unique ability to ramp up the production of their DNA repair genes.
Barrett's work will help Clark-Hachtel build upon this research using local species of tardigrades they collect in Asheville.
"Our knowledge is limited to the lab grown species. We want to be able to see if the wild species have the same stress tolerance as the lab grown species," Barrett said. "One thing we want to do is stress tolerance testing with radiation. We would radiate them at high levels and just see how long they survive? Do they still reproduce? Stuff like that."
Hopefully, this knowledge could be applied to DNA protection and repair in other microscopic organisms, bacteria and even human cells. But undergraduate research has a purpose beyond making discoveries - it cultivates knowledge and hands-on skills, preparing student research assistants, like Barrett, for careers in science.
"My research seeks to involve students in discovering mechanisms of exceptional genome stability and provides students with the opportunity to engage with biological science in diverse ways, from field collection to molecular biology to coding," Clark-Hachtel said.
The first step in their research is finding tardigrades. Luckily, these little eight-legged micro-organisms are practically anywhere there is water.
"Tardigrades can be found anywhere really. They're most commonly found in different types of moss and lichen," Barrett said, "and the diversity of the species is usually equivalent to the diversity in the moss and lichen."
Barrett and Clark-Hachtel, along with two summer research assistants from other universities, go to Sandy Bottom wetlands, research land owned by UNC Asheville, to collect their samples. They grab clumps of a variety of mosses and lichen off of rocks, trees, and nearby streams from all around the forest to increase diversity in the samples.
"I really like being out in the field because it connects back to what you're doing in the lab, and you get really attached to your samples," Barrett said.The samples are then brought back to the lab to extract and cultivate the collected tardigrades. To do this, the moss or lichen is put on a plate with a filter below it. It is left under a light overnight and the tardigrades travel away from the light, through the filter to the water beneath.
The water can then be examined under a microscope and the students use mouth pipettes to isolate the tardigrades out from other microorganisms or debris in the sample.
"We hope to cultivate them so that they are happy and reproduce and we can have hundreds of different species of tardigrades that are in large enough numbers to run further testing on," Barrett said.
Even once isolated in a sample, different tardigrade species are difficult to identify by sight alone, DNA processing is often needed. Barrett said she picked up a lot of hands-on lab processes, including DNA extraction and purifying, that she believes will be helpful in her future classes.
"The upper level biology courses cover a lot of molecular science. I'm doing a lot of that in the lab right now, and I know it will play a part in my further education," Barrett said."Knowing all the skills of cultivating and basic lab procedures, it's very helpful."
Being able to tie her research to her class work helps her grow as a biologist, as well as prepare for a future in the field. The opportunity for one-on-one research training was one of the reasons she came to UNC Asheville, Barrett said.
"There's a lot of opportunities to be involved in research under a professor at UNC Asheville that you would not get at other, bigger schools," Barrett said. "It is really important to make connections and to get involved. Everyone is really nice and will help you find your place in undergraduate research."