We are hard to say which animal is the most poisonous in this world, but there is no doubt that the poisonous frogs of the golden skin that originated in Colombia (also Called golden arrow frogs) belong to one of them. But why their toxins do not hurt themselves?
This arrow frog, the skin was golden yellow, looks very cute, but in their skin glands there is a alkaloid toxin – arrow frog toxin
The content of these toxins is enough to kill ten people. If toxins enter your blood, you are likely to live for ten minutes. There is currently no discovery of any antidote, and the known resistance to this arrow frog toxin is only one snake.
However, arrow frogs do not synthesize this toxins in their bodies. When we captive these arrows frogs, rather than let them in the natural environment breeding, they are completely harmless. This reminds us of the arrow frogs like toxic puffer fish, their toxins from the body of food.
So why are they not poisoned by themselves? In order to solve this problem, the New York State University (SUNY) of the relevant researchers to mice as the experimental object to study.
Researchers have found that
arrow frog toxins can open the sodium channels on nerve cells, and this process is irreversible and therefore can permanently block the transmission of nerve signals to muscle cells, resulting in muscle Persistent tension can not relax, and the heart is more susceptible to the impact, eventually leading to poisoning heart failure and death.
tetrodotoxin is actually caused by toxic affect the normal operation of the sodium channel, but a slightly different mechanism of any connection with dart frog toxins.
Researchers Sho-Ya Wang and Ging Kuo have found the mutant amino acids that have fondered the frogs.
First, they found five natural amino acid substitutes in the golden arrow frog muscle and were tested in the muscles of the mice. When the five amino acids of the mice were replaced by the mutant amino acids of the arrow frogs, the muscles of the mice were also able to resist the arrow frog toxin.
In order to figure out which amino acid mutations work in the end, the researchers’ next step is to replace and exclude the five amino acids. Finally found that, in addition to the N1584T this alternative, the other can not maintain resistance to arrow frog toxins, and in this mutation, amino acid asparagine was replaced by threonine.
The results of the New York State University research team show that, like puffer fish, the resistance of the arrow frog to its toxins is mainly due to a single gene mutation. Prior to this, a study by Harvard University research team showed that the resistance of the arrow frog to its toxins was due to a variety of factors.
Although the mystery of the arrow frog toxins appears clearer, it does not mean that we can find the antidote, and there is no known antidote for tetrodotoxin. The aim of this study was to find the gene mutation that survived the frogs that were endangered by their own toxins.
The study concludes: “There is an effective rNav1.4- N1584T substitution on the sodium channel of the golden arrow frog muscle, which makes the arrow frog toxin almost impossible to play a normal role. Automatic resistance. Our experimental results provide a strong support for this conclusion. “
” If this mutation occurs in reverse, then the frog on the toxin is still a certain degree of resistance? As we guess, The automatic resistance to toxins in arrow frogs is not with the body, but with the gradual increase in evolution, of course, it is worth our further study. “ The study published in the” United States Journal of the Academy of Sciences.