A study led by the University of Queensland found that the Australian skinks developed molecular armor to prevent Snake Venom to close muscles.
Professor Bryan Fry of UQ’s School of Environment said he revealed exactly how Skinks avoids death can inform biomedical approaches to the treatment of Snakebite in humans.
“What we saw in Skinks was evolution in its most demanding,” said Professor Fry.
“The Australian skinks have developed small changes in the critical muscle receptor, called the nicotine acetylcholin receptor.
“This receptor is usually the aim of neurotoxins that bind to it and block the communication of the nervous muscle, causing rapid paralysis and death.
“But in a stunning example of a natural counterpoint, we found that on 25 skinks occasions, the mutations in this binding place were developed independently to block Venom from the connection.
“It is a testimony of massive evolutionary pressure than poisonous snakes after their arrival and expanding on the Australian continent if they feast on the defenseless lizards of the day.
“Incredibly, the same mutations have evolved in other animals such as mongoosis that feed on cobras.
“We have confirmed our functional testing that the main Australian skink (Bellatorias Frerei) has evolved exactly the same mutation of resistance that gives the dachshund of honey, it is the famous resistance to the cobra poison.
“Seeing this same type of resistance evolves in the lizard and the mammal is quite remarkable – evolution constantly hitting the same molecular Bullseye.”
Mutation of the muscle receptor in the skins included a mechanism for adding sugar molecules for physical blocking of toxins and replacing the protein building block (amino acid arginine in position 187).
Laboratory work verifying mutations was carried out in UQ adaptive biotoxicological laboratory Dr. Uthpala Chandrasecara, who said it was incredible to testify.
“We used synthetic peptides and receptor models to imitate what happens when Venom enters an animal at a molecular level and the data was crystal clear, some modified receptors simply did not respond at all,” Chandrasecara.
“It is fascinating to think that one small change in protein can mean the difference between life and death when facing a highly poisonous predator.”
One day, the finding could inform about the development of new antivenics or therapeutic substances to face neurotoxic poisons.
“Understanding how nature neutralizes Venom can offer traces for biomedical innovations,” Dr. Chandrasecara.
“The more we learn about how the poison is in nature, the more tools we have for the design of new antivenics.”
The project included cooperation with museums throughout Australia.
Research has been published in International Journal of Molecular Sciences.
