New Tardigrad-like reveals secrets of radiation resistance
New Tardigrad-like reveals secrets of radiation resistance
A newly described type of beard gives scientists insights into what makes these tiny, eight -legged creatures so resistant to radiation.
Bärtierchen, also known as water bears, have long fascinated scientists with their ability to survive extreme conditions, including radiation at a level that is almost 1,000 times higher than the fatal dose for humans. There are about 1,500 known bearded species, but only a handful is well examined.
Now scientists have sequenced the genome of a scientifically new way and showed some of the molecular mechanisms that give bears their extraordinary resilience. Your study, published in Science on October 24 1 Identify thousands of caretonal genes that are more active when exposed to radiation are. These processes indicate a sophisticated defense system that protects DNA from the damage, causes radiation, and repairs that occur.
The authors hope that their findings can be used to protect astronauts during space missions from radiation, to eliminate nuclear contamination or to improve cancer treatment.
"This discovery could help improve the stress resistance of human cells, which benefits patients who undergo radiation therapy," says Lingqiang Zhang, co-author of the study and molecular and cell biologist at the Beijing Institute of Lifeomics.
protection genes
About six years ago, Zhang and his colleagues went to the Fiiu mountains in the Chinese province of Henan to collect moss samples. In the laboratory and under the microscope, they identified a previously not documented bearded animal species, which they called Hypsibius Henanensis. The genome sequencing showed that Art 14,701 had genes, of which 30 % are unique for beards.
When the researchers H. Henanensis exposed radiation boxes of 200 and 2,000 gray-far beyond what people could survive-they found that 2,801 genes that are involved in DNA repair, cell division and immune responses were active.
"It is like in the event of war when factories are converted to produce ammunition. It is almost at the level at which gene expression is being redesigned," says Bob Goldstein, cell biologist at the University of North Carolina in Chapel Hill, who has been studying beards for 25 years. "We are fascinated by how an organism can change its gene expression in such a way that it produces so many transcripts for certain genes."
one of the genes, called Trid1, encodes a protein that helps to repair double strand breaks in the DNA by recruiting specialized proteins at the damage sites. "This is a new gene that, as far as I know, nobody examined," says Goldstein.
The researchers also estimate that 0.5–3.1 % of the bearded genes were acquired by other organisms by a process called horizontal gentleman. A gene called doda1, which apparently comes from bacteria, enables beards to produce four types of antioxidant pigments known as Betalaine. These pigments can neutralize some of the harmful reactive chemicals that cause radiation in cells, and which make up 60–70 % of the harmful effects of radiation.
The authors treated human cells with one of the Betalaine of the Bärtierchen and found that these cells were much better able to survive radiation than untreated cells.
no expiry date
The examination of the molecular mechanisms that enable beards to tolerate other extreme conditions such as high temperatures, air withdrawal, dehydration and hunger could have far -reaching applications. For example, it could improve the durability of sensitive substances such as vaccines. "All of your medication have an expiry date - bearing notes," says Goldstein.
The comparison of these mechanisms between different types of beards is an important part of this research, adds Nadja Møbjerg, animal physiologist at the University of Copenhagen. "We don't have enough knowledge about the different types of beards that exist," she says.
These animals have "a wealth of protective substances that will probably offer even more interesting and useful knowledge," says Goldstein. "We want to understand how they work and what potential they have."
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Li. L. et al. Science 386, EADL0799 (2024).