In a world first, researchers have reared cone snails in a laboratory aquarium, which presents huge potential for understanding and unlocking the power of their complex venom for a vast range of human therapeutics.
It’s estimated up to 1,000 different cone snail species exist, each with their own special recipe of venom. Each type of venom contains hundreds of compounds, so it's no surprise it's already of huge interest to scientists who have so far discovered the potential for painkillers, insulin regulation and more.
Now, the breakthrough of not just discovering a new venom but successfully rearing cone snails in a lab enables a more sustainable way of accessing their deadly conotoxins is a win for both drug development and biodiversity. And it's also enabled the University of Queensland (UQ) researchers to chart biological changes in the different life stages of the animals, including the makeup of their complex venom.
“Juvenile cone snails use a different cocktail of venoms than adult snails to kill their prey,” said Richard Lewis professor at the Institute for Molecular Bioscience, UQ. “This is a rich and unexplored group of molecules that we can now examine as potential leads for drugs.”
The mollusk at the center of it all is the Conus magus, or the magical cone/magician’s cone, depending on who you ask. And it does appear to have a few tricks hidden in its juvenile and adult venom varieties.
As well as compounds involved in analgesics, the scientists discovered that peptides produced by the juveniles had the potential to block nicotinic acetylcholine receptors, which could lead to new therapies to help smokers quit.
“A lot of our success with venom molecules has been in developing pain medications, but depending on the pharmacology we’ll see if it has therapeutic potential for any of the disease classes,” Lewis added.
While the snail is capable of stinging a human, the lethal strikes are left to their much larger relatives like the Conus geographus. That is, unless you’re a fish (or, as the team discovered, a marine bristle worm).
The adults capture fish with a set of paralytic venom peptides and a hooked radular tooth that gives the jabbed fish no chance of escape. As juveniles, they “sting-and-stalk” polychaete worms, and their venom rapidly slows the prey so they can devour it without a struggle.
“They jab the worm with a harpoon-like structure before injecting it with venom to subdue it,” Lewis said, of the activity you can see in a video below. “The juvenile snail then slowly stalks the worm and sucks it up, like a small piece of spaghetti.”
The ability to rear the snails from eggs to adults, for the first time, has allowed scientists to get a crucial look at their molecular and morphological changes throughout their life cycle. While the snails are found throughout the Pacific and Indian oceans, and the Red Sea, little is known about their early life stages.
“This is because their eggs, larvae and juveniles are so hard to find and difficult to rear in an aquarium,” Lewis said.
Now, the team – which also includes Aymeric Rogalski and Himaya Siddhihalu Wickrama Hewage – has a successful and sustainable population of these fascinating animals that present untapped medical potential.
The research was published in the journal Nature Communications, and check out the juvenile cone snail enjoying its worm 'spaghetti,' and the rare sight of an adult female laying eggs, in the videos below.
Source: University of Queensland
