Why this octopus does not die in any way? / Picture
Their survival strategy is a multi-dimensional superhero; At first a repressor protein protects their DNA, the “Tune” state leads to limb shrinkage and a significant decrease in their internal water reserves, greatly increasing their ability to survive, and now scientists are discovering a new dimension to this superhero. discovered
According to online news, a group of scientists led by biologist Courtney Clark Hochtel from the University of North Carolina at Ashton blasted the tardigrades with gamma rays and observed their reaction; “What we saw surprised us,” said biologist Bob Goldstein of the University of North Carolina at Chapel Hill. “The tardigrades did something we didn't expect.”
For decades, the amazing resistance of tardigrades to radiation has amazed humans; They can tolerate about 1000 times the dose that is lethal to humans and continue their little lives; As if nothing happened.
A damage-suppressor protein, Dsup, is thought to be involved in this for some tardigrades, but not all species of tardigrades have Dsup or its homolog, suggesting they have another means of survival; To find out, the researchers studied the effect of gamma radiation on a species of tardigrade called “Hypsibius exemplaris”.
They placed the tardigrades in a tabletop irradiator that exposes the creatures to gamma rays emitted by the beta decay of cesium-137. They exposed tardigrades to specific doses; A lower tolerable dose and a much higher average lethal dose.
Instead of using a pre-damage protection strategy, tardigrades increased the production of DNA repair genes. By 24 hours after exposure, the tardigrades had repaired most of the DNA broken by ionizing radiation.
Next, researchers expressed some tardigrade repair genes in Escherichia coli culture and exposed samples of this bacterium to ionizing radiation. Bacteria inoculated with genes from tardigrades had similar DNA repair abilities.
“These animals have an incredible response to radiation, and that seems to be the secret to their extreme survival abilities,” said Clark Hochtel.
