Utah State University Uintah Basin’s Charles Hanifin is in uncharted waters.
The associate biology professor recently returned from Japan with 700 micrograms of 6-epitetrodotoxin, the highest quantity of purified toxin ever collected that is only found in select newts.
“We hope to identify why the toxicity levels of newts vary compared to other marine animals,” Hanifin explained. “And if environmental factors and natural selection make an impact, or if the newts are evolving to adapt to increased evolutionary resistance to the toxicity of their predator, the snake.”
Twenty years ago as a graduate student in USU’s biology department, Hanifin became interested in the coevolutionary relationship between toxic newts and the snakes that could eat them. However, since the resources and expertise weren’t available at the time in USU’s lab, questions lingered for Hanifin.
He applied for a National Science Foundation grant and was awarded a joint grant between the NSF and the Japanese Society for Promotion of Science. The grant covered three months of travel and internships for grad students to be trained at Tohoku University in Sendai, Japan.
Working with Tohoku professor Mari Yotsu-Yamashita, Hanifin learned the techniques to measure tetrodotoxin (TTX) and 6-epitetrodotoxin at the only lab in the world set up to accomplish the process. Hanifin collected data on the distribution of TTX in newts and published a paper on his findings for his doctorate dissertation.
Two decades later in October 2019, Hanifin was able to return to the Yotsu-Yamashita lab to isolate the compound from newts. He utilized chromatography to separate compounds from other chemical forms of TTX in order to isolate the specific 6-epitetrodotoxin.
“No one has tested toxicity of these compounds and no one has tested the resistance of snakes,” Hanifin said. “We hope to discover why the sodium channels in some snakes are resistant to toxins, and identify if snakes evolved their channels to be TTX resistant, if snakes are becoming more resistant and if some populations of newts are making a more unique form of TTX to become more toxic.”
Over the next few months, Hanifin will be using electrophysiology to generate synthetic snake sodium channels. Using frog eggs to make the channels, they will study the impacts of exposure to the 6-epitetrodotoxin toxin.