Stinging plants are widespread globally, with certain species posing health risks to humans. Notably, Dendrocnide species in Australia and Urtica ferox in New Zealand are known for their painful stings. While extensive research has been conducted on their morphology, the composition and full effects of their venom remain poorly understood.
Recent studies have identified nociceptive peptides, gympietides from Dendrocnide species (Gilding et al., 2020) and urticatoxins from Urtica ferox (Xie et al., 2020), that activate voltage-gated sodium channels, suggesting a common molecular mechanism underlying their pain-inducing effects observed in vivo.
Although Urtica and Dendrocnide plants appear to share a similar defensive strategy, our findings reveal that their venom compositions are distinct. Further investigation into the mode of action of Dendrocnide venom suggests a unique mechanism involving lipid transfer proteins (LTPs) and gympietides. While LTPs are commonly found across the plant kingdom, this is the first time they have been identified as components of a plant venom, highlighting a novel functional role for these molecules in plant defense.
This research project aims to elucidate the evolutionary relationship between Dendrocnide and Urtica, and to investigate the role of LTPs as a venom component, and ultimately to better understand plant venom mechanisms of action in human pain pathways.