Poison dart frogs
in the amazon have developed a resistance towards the poison they carry on their
bodies. The frogs have evolved to not use the protein that the poison attaches
to. The toxin is called epibatidine, “a substance so poisonous
that just a few millionths of a gram can kill a mouse.”
It is found in a
certain type of food that only the frogs are able to eat. Studies were done
using frog eggs and switching of selected amino acids of that specific protein.
The toxin binds to a protein in the cell that also binds to acetylcholine. Acetylcholine is a messenger that is
necessary for brain function. The frogs use resistance with “other amino acid replacements elsewhere in the receptor
protein appear to have compensated, Borghese and Tarvin found, creating a
protein that won’t let the toxin latch on, but that still responds normally to acetylcholine.”
The frogs that are resistant have different amino acids in the protein
that allow it to still bind to acetylcholine but not to the toxin. Only a few
species of the poison dart frog have developed this resistance to the toxin.
The other frogs use a different toxin as their defense.
"One step for man, one giant leap for frog-kind" - Britt
