All cells in our body have the same DNA, but not all of them express the same genes.
For example, in eye cells there is no point in gene expression responsible for the synthesis of insulin, so the cell has its own mechanism to prevent it from taking place.
It has been known since the 1980s that this is achieved through DNA folding, which exposes abroad only the genes that must be expressed in each cell, hiding on its inner face those that are not necessary. However, recently a group of physicists from the Leiden University has managed to demonstrate how exactly it happens thanks to a computer simulation.
Why is DNA folded?
In total our body contains some two meters of DNA;something that, as you will understand, must be very well rolled up to leave room for the rest of the components of our body.
So our genetic material it’s found perfectly folded inside the cells thanks to a set of proteins that perform the same function as our mothers when they put all the summer clothes and a couple of coats in case it gets cold.
However, the function of said folding it is not restricted only to Retrench of space, but also intervenes in the gene selection that will be expressed in each cell. As you know, DNA is made up of a series of letters, which are grouped together forming amino acids which in turn will unite to form all the proteins necessary to cover all the functions of the organism. The problem is that not all cells perform all functions, so some of these proteins are unnecessary.
To avoid the cost of producing something that is not beneficial at all, DNA folds strategically, making the regions that contain that information remain inaccessible to ribosomes, which are the ones in charge of synthesizing the proteins.
How can DNA folding exactly hide regions that are not needed for the cell?
Thanks to a computer model which simulates the genome of two types of yeast, a group of physicists from the Leiden University, in the NetherlandsThey have been able to step back and verify that the commands indicating how the genetic material should be folded are contained in a second layer of information within the own DNA.
A boat soon this may seem like a minor discovery, but it turns out of great importance, since knowing these signals in depth, scientists could manipulate them to hide the expression of genes responsible for diseases. At the moment it is only a distant dream; but who knows? Following the path that they have started to walk in the future could become a reality.