A protein that helps to synthesize DNA is different in modern humans than in nendrilles and densovins – our closest relatives – and new experiences in mice that have been changed to indicate genetically modern human version indications that have treated us in different ways.
Researchers suggested in a new research, as a result, the discovery can be highlighted as to why Nanderthils and Denisovin disappeared.
But the importance of consequences is not yet clear for humans.
“It is too early to translate these results directly into humans, because the nerve circuits of the rats are quite different.” Xiangchaun thatPost Documentary Researcher at the Okinawa Institute of Science and Technology in Japan, Japan, Said in a statement. However, this work indicates that the variety of modern humans can give us some evolutionary benefits in special tasks compared to native humans, such as to counter short resources.
Key protein
Previous research has revealed that modern humans withdrew from their nearest evolutionary relatives, nandrotals and densovans, About 600,000 years ago. It is unclear why modern people survived while our close relatives died.
To solve this mystery, Looking for potential genetic consequences, researchers analyzed the enzyme adsl (Adenylosuccine Lyase). This protein helps to synthesize Purna, one of the basic buildings of DNA and other important molecules.
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“There are very few enzymes than evolutionary changes in the ancestors of modern humans, which are a small number of enzymes. ADSL is one of them.” Sweet piboFor, for, for,. Nobel LaureateThe leader of the Human Entertainment Genomix Unit at the Okinawa Institute of Science and Technology in Japan, and the director of the Max Planck Institute for evolutionary humanity in the German city of Legesg, said in a statement.
ADSL 484 is made of amino acid chains. The version of this enzyme found in practically all modern humans has been seen in both Nandartles and Denisovan through only one amino acid – the 429th amino acid in ADSL is the volunteer in modern humans, but our extinct relatives.
Scientists noted that ADSL variants are seen in modern humans and not in relatives near us, and then we appeared after being separated from the lineage, which led to nandrotals and Denisovine. Because of this, researchers investigated the effects of the potential conduct.
Last research about lab cells has shown that ADSL, which is displayed in modern humans, has produced a more unstable version of the enzyme that breaks faster than Nandtals and Denisovan.
Changes to behavior
New research published in the Journal on August 4 pnasLikewise, it is found that, in mice, modern different types of chemical substances that ADSL usually works to synthesize purene in multiple organs, especially in the brain. The detection endorsed the idea that the modern human version of the ADSL is less active than the various types of visible in Nandartles and Denisovans.
In these experiments where mice learned that they can get water beverage after specific lights or sounds, female mice have been genetically modified to obtain a version of ADSL as it looks like the appearance of modern humans. It can suggest that female mice have been improved in learning to connect the dots between water and light or sounds to the variety of humans, or to somehow to find water in some way.
With the modern humanity of enzyme, the behavior of female mice and the changes in the ADSL level were not seen in males. “It is not clear that only female mice get a competitive advantage,” co -authors of the study Ezomy FukonaA researcher at the Okinawa Institute of Science and Technology said in a statement. “The behavior is complicated.”
Statistics tests that analyze the Nandruthal. Denswan; And modern African, European and East Asian DNA found that changes in ASDL genes appear at a higher rate than random changes in modern human genomes, which makes it likely that these variations provided some evolutionary benefit.
Perhaps compared to the new results, earlier work has shown that the genetic disorders that cause ADSL deficiency in modern humans can lead to intellectual disability, speech and language defects and other problems. This shows that during evolution, modern humans had to balance the potential benefits of reducing ADSL activity that could arise from ADSL deficiency, co -author of the study Shin Yu LeeAlso, at the Okinawa Institute of Science and Technology, said in a statement.
The implications unspecified
Not everyone thinks that there are direct implications of this study as to why a modern human being has flourished or because Nandrotals or Denisovins have disappeared.
The results in mice “don’t say more about human evolution at this stage,” Mark CoardA specialist at Simon Fraser University in British Columbia, who did not participate in the research, told Science directly.
However, the strategy to use mice to study the effects of genetic differences between modern humans and our close relatives between modern humans and our close relatives, “is very promising as a method of investigating the evolution of our brain and behavior.” “I hope we will see such a breeze in the next few years.”
Future research can investigate a specific mechanism by which a change in ADSL activity affects behavior. Scientists can also discover how ADSL’s activity is associated with other behavior and how many genetic changes in the concert can work.
