How the new method of "activating and deactivating" genes for the possible cure of serious diseases

Understanding how our genes work is an increasingly useful and effective task for fighting diseases that seemed impossible to overcome a few years ago.

And in the midst of the medical-technical revolution we are living, the progress of genetic studies is essential to give more hope of life. Thus, an international team of scientists with the participation of researchers from the Spanish National Research Council (CSIC) has succeeded in advancing the understanding of the functioning of mechanisms of genomic organization of cells.

The studies carried out, whose results were published in the journal "Nature", address the complex interaction between chromatin (the structure that represents the base of eukaryotic chromosomes) and a series of regulatory proteins, which act as switches that activate or silence the genome.

With many examples, researchers explain that the human body contains a "wide variety" of cell types. "Every type is characterized by the expression of a specific set of genes. In animals, plants and fungi, DNA, which is the basic structure of genes, is packed with proteins to form chromatin, "they said in the study.

Thus, they claim that the control of gene expression requires a "complex interaction" between chromatin, which contains the hereditary message, and regulatory proteins.

"This interaction can be translated into different regions of the genome active (euchromatin) or silent (heterochromatin.) In general, heterochromatin accumulates at the periphery of the nuclei, while euchromatin is found at inside them, "they add.

To identify the proteins involved in the separation between euchromatin and heterochromatin and their positioning in the nuclei, the researchers designed a series of experiments using as model organism a "Caenorhabditis elegans", a species nematode of the family Rhabditidae measuring about 1 mm. in length and lives in temperate environments.

"Although it is a small animal of simple morphology, it shares many genes with other organisms and with humans, and it is transparent, which means allows us to study its "living" tissues during embryonic development, "they explain.

"Chromatin regulation is important for maintaining cell identity and preventing excessive proliferation.Every time, it is becoming increasingly evident that epigenetic changes, which are changes in DNA, are important in many cell types, Peter Askjaer, researcher at CSIC, who works at the Andalusian Center for Developmental Biology (CSIC University – Pablo de Olavide University – Junta de Andalucía), explains one of the leaders work.

In this work, scientists identified a protein called MRG-1 (called MRG14 or MORF4L1 in humans), responsible for the accumulation of heterochromatin in the nuclear periphery early in development.

"We have discovered that in the absence of MRG-1, other euchromatin proteins invade the heterochromatin regions and alter their activity and their position. Other terms: MRG-1 is needed to restrict the access of gene expression factors from echromatin to heterochromatin, "says Askjaer.