Thomas Boothby (right), a University of Wyoming assistant professor of molecular biology,
and Anthony Trent, a UW senior from Laramie majoring in molecular biology, work with
a tardigrade under the microscope that they can view on a computer screen. Boothby
recently received a nearly $100,00 NASA grant to study the effects of long-term radiation
on tardigrades and nematode worms in an effort to help better prepare astronauts for
space flight. (Vincent Nicholson Photo)
Thomas Boothby, a University of Wyoming assistant professor of molecular biology,
recently received a nearly $100,00 NASA grant to study the effects of long-term radiation
on tardigrades and nematode worms in an effort to help better prepare astronauts for
space flight.
By studying how the tiny creatures cope with acute and chronic exposure to ionizing
radiation, Boothby hopes to better understand the commonalities and differences between
these types of exposures. This will allow NASA to better formulate safeguards, countermeasures
and therapies for protecting astronauts, which Boothby says will be essential for
fostering a safe and productive long-term human presence in space and supporting the
United States’ space economy.
“During space flight, humans are no longer protected by Earth’s atmosphere and, therefore,
are exposed to dramatically increased levels of radiation. This can have severe detrimental
effects on our physiology and health,” Boothby says. “Most of the research that has
been done with regard to the effects of radiation has looked at acute single exposures
to radiation. But, of course, in space, astronauts do not experience just one single
large dose. Rather, they must tolerate and cope with long-term chronic exposure to
radiation.”
In 2020 and 2021, tardigrades from Boothby’s UW lab were part of an experiment on
the International Space Station aimed at better understanding changes to their gene
expression as they experienced stressful environments in space.
Now, tardigrades and nematode worms are being used because they provide unique insights
into how animals can suffer from or cope with radiation, Boothby says.
“Nematode worms, like humans, are susceptible to radiation damage, while their cousins,
the tardigrades, are one of the toughest organisms we know of when it comes to surviving
high doses of radiation,” he says. “By using these two organisms, we will be able
to see not only how acute or chronic radiation exposure negatively affects the biology
of the worms, but we also will be able to gain insights into how tardigrades are able
to combat the detrimental effects of these stresses.”
This illustration shows a tardigrade. (Shuttershock.com Photo)
Tardigrades are renowned for surviving a number of environmental stresses, including
being dried out, frozen and heated to temperatures above the boiling point of water.
They also can go for days or weeks with little or no oxygen; survive extremes in pressure,
including the vacuum of outer space; and have been shown to survive up to 1,000 times
as much radiation as typical animals and humans can.
“Because they are so tough, we expect that tardigrades will be able to mount protective
or reparatory strategies to cope with both acute and chronic exposure to radiation,”
Boothby says.
According to the grant proposal summary, the goal of the project is to understand
how prolonged low-dosage exposure to ionizing radiation affects different biological
systems at the level of genome integrity, gene expression, and developmental and reproductive
biology.
“There are different types of radiation: ionizing and nonionizing. Ionizing radiation
is much harsher and causes a lot of damage to biological systems,” Boothby explains.
“Ionizing radiation also happens to be much more prevalent in space environments.
We are using X-rays because they are a ready source of ionizing radiation and ultraviolet-C
light because it is nonionizing. By using these different types of radiation, we will
be able to see if nematodes and tardigrades are affected differently by these different
types of radiation.”
The grant provides funding for one UW graduate student to help perform the experiments.
While this position is not yet filled, Boothby says Anthony Trent, a UW senior from
Laramie majoring in molecular biology, is already part of the grant research team.
“My role in the research is conducting some experiments pertaining to some of the
aims of the grant, including experimentation about fractionated versus acute irradiation
effects on tardigrades,” Trent says.
While no exact dates are set, Boothby expects the grant to start this October and
run through September 2023.
