Russian scientist discovered in DNA an additional "cache" with genetic memory

Russian scientist discovered in DNA an additional "cache" with genetic memory



Maxim Nikitin from the Moscow Institute of Physics and Technology proved that in addition to a double macromolecule, “cellular debris” can transmit hereditary information

The world-class discovery was made by Russian scientist, head of the MIPT laboratory Maxim Nikitin. He discovered a "secret" system for storing genetic information in DNA, which no one paid attention to before. Our memory, propensity or resistance of the body to dangerous diseases may depend on it. More details about this work, published recently in Nature Chemistry, were told to us by the scientist himself and commented on by his biologist colleague.

First, let's remind readers what DNA (deoxyribonucleic acid) is. This is one of the macromolecules of our body (there are also RNA and proteins), which ensures the storage and transmission of hereditary information from generation to generation. This information is recorded in DNA in the form of an individual genetic code for each living being - a sequence of only four nucleotides (they are denoted by the letters A, G, T, C).

In 1953, scientists James Watson and Francis Crick discovered the double helix structure of the DNA molecule. The second chain in it also consists of the same four letters of the genetic alphabet and is firmly connected with the first.

They relate to each other like parts of a zipper on your jacket,” explains Sergey Kiselev, head of the laboratory of epigenetics at the Institute of General Genetics of the Russian Academy of Sciences. - That is, they are a dense "clasp". As a rule, the length of the helix is ​​several hundred million nucleotides, the same four letters in different sequences. And the more links of the "lightning" (or double helix) are complementary to each other, that is, they form a strong bond with each other, the stronger the common "storage" - DNA. But imagine that some links from the “lightning” suddenly flew out, and the letters no longer coincided with each other, as before. In this case, geneticists usually ascertain the presence of a mutation in a certain section of DNA, that is, in a gene.

Maxim Nikitin decided to study what would happen if all such connections were suddenly lost in DNA. What will happen if a large DNA suddenly collapses into many small fragments and, accordingly, breaks the pairs of letters that were fastened together? The scientist worked for nine years, modeling such a "catastrophe" from the DNA "pieces" present in any cell, consisting, for example, of only 10-20 nucleotides. They used to be called "junk DNA", which is present in every cell and, as previously thought, does not carry any information to descendants. So Nikitin proved that these little pieces are also capable of transmitting information! In the experiment, he saw a change in the cell caused by precisely such short molecules. By themselves, they did not even reach one gene - there were not enough nucleotides in the desired sequence. But it turned out that they are able to solve the problem by finding common ground with their own kind, and thus create conglomerates that make up whole genes.

“Such bonds of disparate DNA links can be called weak interactions in a cell,” says Nikitin. - So far I have demonstrated them in a test tube, but this mechanism can definitely be realized in nature. Now we need to understand how? The first option may be due to the fact that this is some kind of chaotic entity that prevents the building of a strong genetic system. The second is that this mechanism is involved in natural processes. For example, I have a version that this mechanism can be convenient for the formation of our short-term memory process.

If this can be proven, then, according to Nikitin, humanity will have "the front door to improve memory and slow down aging." In addition, using this ability of our DNA, we can make drugs safer, without side effects, or even create a supercomputer that builds billions of computational options based on the interaction of DNA fragments.

According to Sergei Kiselev, the mechanism of information transmission described in the work of Maxim Nikitin is a bit like an epigenetic mechanism that strengthens or weakens the work of genes due to mRNA molecules. As we know, in response to external stimuli, for example, nutrition, emotional stress, physical activity, the epigenome gives “orders” to our individual genes to increase or, conversely, weaken their activity. How and what affects the new mechanism of weak interaction in the cell remains to be seen by scientists.

According to Nikitin, who has already received many invitations to international scientific conferences, he "discovered a property that has long remained in the shadow of the elegance and beauty of the DNA double helix." He compared the event to how if we previously knew only one Sun, and then accidentally found out that in fact there are billions of such stars in the Universe.



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