A team of researchers from the University of Queensland have discovered a previously unidentified neurotoxin that is similar to the venom found in spiders and cone snails. Australia is home to some of the world’s most dangerous wildlife. Anyone who spends time outdoors in eastern Australia is wise to keep an eye out for snakes, spiders, swooping birds, crocodiles, deadly cone snails and tiny toxic jellyfish.
In the forests of eastern Australia there are a handful of nettle trees so noxious that signs are commonly placed where humans trample through their habitat. These trees are called gympie-gympie in the language of the Indigenous Gubbi Gubbi people, and Dendrocnide in botanical Latin (meaning “tree stinger”).
Researchers hope the study, published Wednesday in the Science Advances journal, will help provide new information as to how pain-sensing nerves function, and help in developing painkillers.
“The Australian stinging tree species are particularly notorious for producing an excruciatingly painful sting,” said Irina Vetter, associate professor at the University of Queensland’s Institute for Molecular Bioscience, in a statement.
The Gympie-Gympie, known scientifically as Dendrocnide moroides, can grow to 10 feet tall with leaves 20 inches long. Similar plants normally contain small molecules such as histamine, acetylcholine and formic acid, but none of these cause the severe pain elicited by Gympie-Gympie trees, which suggested to researchers that there was an unidentified neurotoxin to be found.
The team discovered a new type of neurotoxin, coined as “gympietides” — which they named after the plant.
“Gympietides are similar to spider and cone snail toxins in the way they fold into their 3D molecular structures and target the same pain receptors,” said Vetter. “This arguably makes the Gympie-Gympie tree a truly ‘venomous’ plant.”
Vetter said that the long-term pain caused by the trees may be explained by the gympietides permanently changing the sodium channels in a person’s sensory neurons, as opposed to the plants’ fine hairs getting stuck in skin.
“By understanding how this toxin works, we hope to provide better treatment to those who have been stung by the plant, to ease or eliminate the pain,” added Vetter.