Spanish scientists have discovered that a more complex and specialized regulation of genes was key in the genomic process that enabled the transition from invertebrates to vertebrates and contributed the evolutionary success of these.
The investigation, what publishes the magazine 'Nature', has collected genomic, epigenomic and functional data from various organisms, and provides information on the changes that led to greater complexity in vertebrates, especially in the nervous system, according to Efe.
The vertebrates, an animal group to which humans belong, are very diverse and have colonized all the ecosystems of the planet, but scientists They did not know what changes in the genome have contributed to their evolutionary success.
Now, an international team of scientists led by Spanish researchers from the Center for Genomic Regulation (CRG), the Higher Council for Scientific Research (CSIC) and the National Center for Scientific Research (CNRS) in France, has described the processes that made the transition possible from invertebrates to vertebrates.
According to the group leader at the CRG and one of the leaders of this study, Manuel Irimia, "vertebrates share a set of unique gene regulation systems, which allows the information contained in our genome to give rise to a multitude of of functions and, consequently, we have hundreds of specialized cells, tissues and organs ».
"We have analyzed the genomic regulation of different species and we have found two key differences: our genes have a much more complex regulation than invertebrates and that we have copies of genes that originally did only very general functions, but that in vertebrates they have specialized in much more specific functions, especially in the brain, "Irimia explains.
The scientists studied the genomes of several species of vertebrates such as zebrafish, medaka, frog, chicken, mouse and human fish, and compared them with the genome of the amphioxo, which is an organism that has been used as a research model since the 19th century. .
«Its genome has evolved very slowly and without the duplications that vertebrates have. That is why the amphioxus serves as a reference in evolutionary comparisons to understand the origin of our lineage ", specified Hector Escriva, one of the leaders of the work and researcher at the University of the Sorbonne and the CNRS in Banyuls sur Mer (France).
Scientists have also observed that, although the regulation of genes responsible for basic anatomy are highly conserved between species, vertebrates incorporated more regulatory regions that allowed them to acquire new functions.
«In a similar way to studies done in humans, our study gives us a global view of the different regulatory layers of the genome and describes in detail the origin of the unique characteristics of the genomic regulation of vertebrates, which gave rise to organisms with a morphology much more complex ", according to José Luis Gómez Skarmeta, another of the people responsible for the study, from the Andalusian Center for Development Biology (CSIC-Universidad Pablo de Olavide).
One of the most important results of the work is to understand how the genomic duplications that occurred in the origin of vertebrates contributed to diversify the functions of genes.
"It has been almost 50 years since it was proposed that these duplications were key to our origin, but until now many of these predictions have not been proven", according to Ignacio Maeso, a researcher from the Andalusian center.
"We have seen," he added, "that in most cases there are copies of genes that specialize in specific tissues. This is particularly evident in the brain, where new functions have been incorporated that have been essential for the evolutionary success of vertebrates ». EFE