In a first, deadly cone snails are raised in a lab for drug venom discovery

Researchers from the University of Queensland's Institute for Molecular Bioscience, namely Professor Richard Lewis, Dr. Aymeric Rogalski, and Dr. Himaya Siddhihalu Wickrama Hewage, specialize in studying venoms as potential therapeutics. 

Their new investigations have made notable discoveries regarding the variances in diet, behavior, and toxicity throughout the lifecycle— specifically of the small carnivorous marine species Conus magus.

"Juvenile cone snails use a different cocktail of venoms than adult snails to kill their prey," Professor Lewis said in a press release. "This is a rich and unexplored group of molecules that we can now examine as potential leads for drugs."

Professor Lewis elaborated on their success with venom molecules, particularly in developing pain medications. However, he emphasized that further exploration of the pharmacology of these molecules is necessary to determine their potential therapeutic applications for different disease classes.

What is the 'sting and stalk' hunting technique?

During their research, one unexpected discovery was that juvenile cone snails have a distinct feeding behavior and do not prey on fish like adult individuals of the same species. 

"The juveniles would only eat polychaete worms, which they catch using a specific hunting technique we named 'sting and stalk,'" Professor Lewis explained.

"They jab the worm with a harpoon-like structure before injecting it with venom to subdue it. The juvenile snail then slowly stalks the worm and sucks it up, like a small piece of spaghetti."

Furthermore, the team discovered that cone snails consume microalgae during their larvae stage. Still, their diet transforms once they metamorphose into half-millimeter-long juveniles.

Professor Lewis pointed out that while researchers worldwide have extensively studied adult marine cone snails and their lethal venom, the early life stages of these snails have largely remained elusive. 

He attributed this knowledge gap to difficulties locating eggs, larvae, and juveniles and raising them in an aquarium setting. 

"Dr. Rogalski took up the challenge during his Ph.D., establishing very elaborate aquaculture studies to find out how and what each stage of the snail ate," he added.

Thanks to this initiative, researchers now have a sustainable system that allows them to successfully rear cone snails in a controlled environment and comprehensively study juveniles' life cycles and venoms.

This research was published in Nature Communications on June 13 and can be found here. 

Study abstract: 

Marine cone snails have attracted researchers from all disciplines but early life stages have received limited attention due to difficulties accessing or rearing juvenile specimens. Here, we document the culture of Conus magus from eggs through metamorphosis to reveal dramatic shifts in predatory feeding behaviour between post-metamorphic juveniles and adult specimens. Adult C. magus capture fish using a set of paralytic venom peptides combined with a hooked radular tooth used to tether envenomed fish. In contrast, early juveniles feed exclusively on polychaete worms using a unique "sting-and-stalk" foraging behaviour facilitated by short, unbarbed radular teeth and a distinct venom repertoire that induces hypoactivity in prey. Our results demonstrate how coordinated morphological, behavioural and molecular changes facilitate the shift from worm- to fish-hunting in C. magus, and showcase juvenile cone snails as a rich and unexplored source of novel venom peptides for ecological, evolutionary and biodiscovery studies.