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Fun Science FRIEDay – Weaponized Insulin

Most people have heard of cone snails. They are the genus of venomous marine snails that shoot a poisonous “dart” (hypodermic-like modified radula tooth attached to a venom gland) to attack and paralyze their prey before feeding on it. Smaller cone snails primarily hunt and prey on marine worms, while the larger ones hunt fish. To humans the sting of a smaller cone snail is similar to that of a bee, but contact with larger cone snails can be fatal! Basically they are the badasses of the snail world.

Cone snails are venomous! Their toxin is estimated to be 1,000 times more powerful than morphine. (Photo credit: http://www.siart.karoo.net)

Cone snails are venomous! Their toxin is estimated to be 1,000 times more powerful than morphine. (Photo credit: http://www.siart.karoo.net)

What is interesting and the focus of todays FSF, is the recent discovery that one species of cone snail, Conus geographus, uses weaponized insulin to restrict its prey before engulfing it. Why is this cool and important? Insulin is a hormone produced in the pancreas that regulates blood sugar levels. A failure to control insulin levels, commonly seen in diabetics, can result in decreases in blood glucose levels, which can result in lethargy, dizziness, and lost of consciousness among other things.

So now back to C. geographus badass. This snail releases its cocktail of toxins into the water, insulin forms part of a poison mixture evocatively known as “nirvana cabal”, allowing the snail to immobilize whole schools of fish by sending them into “hypoglycaemic shock”, a condition brought on by plummeting blood sugar levels. Once paralyzed the snail can gore to its hearts content.

The cone snail, C. geographus attacking a fish in sequence (sequence: top left, bottom left, top right, bottom right). (Photo credit: Jason Biggs and Baldomero Oliver)

The cone snail, C. geographus attacking a fish in sequence (sequence: top left, bottom left, top right, bottom right). (Photo credit: Jason Biggs and Baldomero Oliver)

C. geographus is one of the most venomous creatures on Earth, and is known to have killed dozens of people in accidental encounters. Now researchers have a better sense of how and why this snail’s toxin is so potent.

You can read more about this cool snail, and the study to uncover its toxic properties in the journal Proceedings of the National Academy of Sciences.

 

Happy FSF!