Quantitation of tetrodotoxin and its role in understanding the evolutionary and environmental consequences in the newt-garter snake prey-predator relationship
Presentation Type
Poster
Keywords
Newt, tetrodotoxin, analytical, HPLC-FD
Department
Chemistry
Major
Chemistry
Abstract
The production of the potent neurotoxin tetrodotoxin (TTX) by the California newt Taricha torosa and garter snake resistance to TTX is an area of interest to chemical ecologists. It has been proposed that the dynamic between these two species is an evolutionary arms-race. The quantitation of TTX in various newt species is vital to fully understanding the evolutionary and environmental consequences of this toxin. A minimally invasive sampling procedure has been implemented to reduce disturbing the ecological environment and harm to the newts by minimizing the skin punch size, thus leaving the newts with homologous TTX patterns on their skin. The newt skin extracts are analyzed by HPLC-FLD with sub-picomolar detection limits, which allows us to quantify a wide range of naturally occurring TTX levels, ranging from 0.0016 to nearly 25 nmol TTX/mg skin. Sampling across 63 geographical sites in California, our data indicate that the species of Taricha torosa has a wide variance in TTX levels. Previous research performed by Hanifin et. al. suggested that garter snakes have won the arms-race due to a phenotypic mismatch, and newts are incapable of possessing higher toxin levels than resistance levels in the snakes. Our data show newts may actually have overcome the “phenotypic mismatch”. We have found in several populations that newt toxin concentrations can vary over time and in some cases individual newt TTX levels greatly exceed garter snake resistance levels.
Faculty Mentor
David Green
Funding Source or Research Program
Undergraduate Research Fellowship
Location
Waves Cafeteria
Start Date
25-3-2022 2:00 PM
End Date
25-3-2022 3:00 PM
Quantitation of tetrodotoxin and its role in understanding the evolutionary and environmental consequences in the newt-garter snake prey-predator relationship
Waves Cafeteria
The production of the potent neurotoxin tetrodotoxin (TTX) by the California newt Taricha torosa and garter snake resistance to TTX is an area of interest to chemical ecologists. It has been proposed that the dynamic between these two species is an evolutionary arms-race. The quantitation of TTX in various newt species is vital to fully understanding the evolutionary and environmental consequences of this toxin. A minimally invasive sampling procedure has been implemented to reduce disturbing the ecological environment and harm to the newts by minimizing the skin punch size, thus leaving the newts with homologous TTX patterns on their skin. The newt skin extracts are analyzed by HPLC-FLD with sub-picomolar detection limits, which allows us to quantify a wide range of naturally occurring TTX levels, ranging from 0.0016 to nearly 25 nmol TTX/mg skin. Sampling across 63 geographical sites in California, our data indicate that the species of Taricha torosa has a wide variance in TTX levels. Previous research performed by Hanifin et. al. suggested that garter snakes have won the arms-race due to a phenotypic mismatch, and newts are incapable of possessing higher toxin levels than resistance levels in the snakes. Our data show newts may actually have overcome the “phenotypic mismatch”. We have found in several populations that newt toxin concentrations can vary over time and in some cases individual newt TTX levels greatly exceed garter snake resistance levels.