Snakes and Newts A Deadly Secret
Eye of newt and toe of frog that’s part of the witches brew in Macbeth. And when it comes to newts, Shakespeare was on to something. Boil a newt and you’ve got a poison that’s deadly to humans. It turns out that there is an animal who can chow down on newts with impunity. I’m Jim Metzner and this is the Pulse of the Planet.
McGlothlin: Newts have a toxin called tetrodotoxin in their skin that helps defend them from predators.
Joel McGlothlin is an assistant professor of biology at Virginia Tech.
McGlothlin: Most predators when they eat a newt are going to die, because the toxin will block certain proteins in their body that allow their nerves and their muscles to work. And so they’ll become paralyzed and in some cases die. This toxin basically binds into the proteins like a cork in a bottle.
Some populations of garter snakes have evolved the ability to withstand the newt’s poison.
McGlothlin: The reason that snakes are able to withstand the toxin is that their proteins have changed just a little bit. It’s like the shape of the bottle has changed just a little bit, so that the cork doesn’t fit anymore.
It’s not only witches who find poisonous newts useful.
McGlothlin: The newt’s toxin, tetrodotoxin, is something that neuroscientists use all the time in order to understand how our nervous system works. They use it as a tool to be able to block certain nerves, and they’re able to measure currents in certain places because they block currents in other places.
A lot of pain medications work in the same way that the newt toxin does. Understanding the way newt toxins interact with snake proteins may help us discover new medications that we could potentially use in humans.
I’m Jim Metzner and this is the Pulse of the Planet.