Environmental Research Boost
A grant of $286,792 from the National Institute of Environmental Health Sciences provides a three-year boost to the environmental toxicology research of Wade Powell, associate professor of biology, and his students.
The competitive-renewal grant fuels Powell's work examining the effects of environmental contamination by dioxins and polychlorinated biphenyls (PCBs) on the African clawed frog and how that may apply to humans. In a counterintuitive environmental twist, the frogs are able to largely resist damage from the toxic chemicals, which can cause cancer and alter development of the cardio-vascular and nervous systems.
"My interest is in environmental contaminants," Powell said. "Dioxin-like chemicals affect different animals very differently," he said. "To most fish species, for instance, these are very strong poisons. They have a wide spectrum of effects, developmental sorts of things but also cancer. I'm interested in what makes a species or group of animals more or less susceptible to the effects of these poisons."
He set out to learn the biological mechanics of how the frogs dodge the poison bullet. A protein (the low-affinity aryl hydrocarbon receptor) common to vertebrates typically binds with dioxins and triggers changes in cells. By cloning genes, Powell and his students replicate the protein from frogs and compare how it binds with dioxins in various species.
And they are trying to discern the original purpose of the protein receptor. "It's an ancient protein ... more than 400 million years old. Dioxins and PCBs have been with us at significant levels for just 50 or 60 years." It's evident that the protein did not evolve to bind with industrial contanimants. "We've been trying to figure out what it does do," Powell said. "How does it contribute to the development of vertebrates?
"We can take a comparative approach. Looking at similarities and differences in different groups of animals is a good way to get a handle on what's in common, what's the core of all of them. Toxicology was a good jumping-off point, but, ultimately, I view it as a question of basic biology."
Powell and his student research team take advantage of next-generation RNA sequencing to examine how cultured cells react to different chemicals, an effort that could also lead to a better understanding of the frog genome - "and that's cool."
The research is unusual for undergraduates, Powell said. He works with four or five student researchers each year, and each student "takes ownership of a little facet of the project and runs with it." The grant provides for the purchase of equipment and supplies and supports the work of students in the Summer Science Scholars program.