Further From a century it took different generations of researchers to find out what the oldest branch of the animals were the animalsThe first differentiated organism of the plant world that could lead the various variety of fauna in today’s world, including people.
Con The progress in science and technology managed to erase hypotheses until they reached two options in OER -BifurcationIt pointed to the sponges and Combs CombsAlso known as Ctenophores.
This Two atypical specimens groups were those who were more related to the rest of the animals. In turn, they can be considered as brothers groups with each other, although the sponges spend their entire adult lives in one place, filtering the food of seawater and the Combs Combs They are vorarively predators who go through the oceans of the world in search of food.
The Genome of the Pinee
Weld Medusas Peine has unveiled the primitive origin of the genomic regulation of animalsAccording to a study by a team of the Genomic Regulation Center (CRG) and the National Center for Genomic Analysis (CNAG), in Spain.
This study, Published in Nature Magazine and Studyevolved between 650 and 700 million years ago and probably appeared at the start of the evolution of animals, about 150 million years before what was believed.
Life depends on the activation and deactivation of genes at a specific time, and Distal Nomic Regulation may make regions away from the starting point of activating the function of itThrough an extra control layer. This layer has probably helped the first multi -cell animals to build species of specialized cells and tissues without finding out new genes, explains the authors of the study.
The discovery has been possible thanks to the exploration of The taken from many of the oldest branches of the genealogical tree of the animals, including the Pinee such as the “seafar” (Mnemiopsis Leidyi),),, Loose PlacoZoos, the Cnidarians and the sponges.
Genomic regulation even occurs in simpler living beings (including jellyfish), But usually in short distances due to the DNA sequence, with the inflammatory or off -switch placed right next to a gene. This type of genomic regulation is simple and probably as old as life on earth, Enforce the researchers.
Physical folding of DNA
They also need That long -destination -genetic control, or distal regulation, is based on the physical folds of DNA and advanced loopsAnd this allows regions to activate their function from the starting point of a gene.
In this sense they consider “probably” that “critical innovation originated in a Mariens being, in the common ancestor of all existing animals.” This animal developed the ability to fold the DNA in a controlled way, creating loops in the three -dimensional space who were placed remotely apart in direct contact fragments of DNA in a two -dimensional level.
Dr. Iiana Kim, co -author of the study and researcher of the Genomic Regulation Center (CRG) and the National Center for Genomic Analysis (CNAG), admits that I had not expected “This layer of complexity was so old”
OneThe discovery was possible by the exploration of the taken of many animals and single -cell family members who are not animals were also studied, but who share a common ancestor. “You can discover a large amount of new biology that looks strange marine animals,” says Dr. Iiana Kim.
The study co -author and professor of the Icrea (Catalan research institution and advanced studies), Arnau Sebe Pedrós, explains that that Previously compared genomic sequences, but thanks to new methods it can now be analyzed “What genuine mechanisms regulate the function of the genome for all types.” The team used a Micro-C technique to map out how the DNA physically folds in the cells of each of the 11 different species they studied.
10,000 million years in sequence data
The scale, Each human cell nucleus contains approximately two meters DNA and the researchers investigated 10,000 million sequence data to build the map of the 3D genome of each species in detail of the studied.
Although there was no evidence of distal regulation in the single -celled family members of animals, non -Bilateral animals, Just like the quality, the board and the Cnidarians, they had a lot of loopS.
Specifically, De Kwardkam, Mnemiopsis LeidyiThey had more than four thousand loops in the genome, a surprising finding because their genome has around 200 million DNA texts. For comparison: the human genome has 3,100 million letters and our cells can have tens of thousands of loops. EFE / ECOTICIA.COM