Octopus is an extraordinary organism with highly complex brains and unique cognitive abilities among invertebrates. So much so that in some ways it has more in common with vertebrates than with invertebrates. The origin of the neural and cognitive complexity of these animals may lie in a molecular resemblance to the human brain, as a recently published research paper reveals. BMC Biology and Remo Sanges from SISSA in Trieste and Graziano Fiorito from Stazione Zoologica Anton Dohrn in Naples.
Research shows that the same “jump-up genes” are active in both the human brain and the brain of two cephalopod species. Octopus vulgariscommon octopus and Octopus bimaculoides, California octopus. A discovery that may help understand the secret of the intelligence of these fascinating animals.
Sequencing of the human genome revealed as early as 2001 that more than 45% consists of sequences called “skipping genes”, called transposons, through molecular copy-paste or cut-and-paste mechanisms. can be “moved” from one point to another in an individual’s genome. Its function appears to be related to properties such as memory and learning.
In most cases, these moving elements remain silent: they have no visible effects and have lost their ability to move. Some are inactive because they have accumulated mutations over generations; others are intact but blocked by cellular defense mechanisms. From an evolutionary perspective, even these fragments and corrupt copies of transposons can still be useful as “raw material” that evolution can sculpt.
Among these mobile elements, the most relevant are LINE (Long Interspersed Nuclear Elements), exists in hundreds of copies in the human genome and is still potentially active. Traditionally, the activity of LINEs was thought to be just a relic of the past, a relic of evolutionary processes involving these mobile elements, but in recent years new evidence has emerged to suggest that their activity is precisely regulated in the brain.
There are many scientists who believe that HAT transposons are associated with cognitive abilities such as learning and memory.: they are especially active in the hippocampus, the most important structure in our brain for neuronal control of learning processes.
A genome rich in ‘jumping genes’
The octopus genome, like ours, is rich in “jumping genes”, many of which are inactive. Focusing on transposons that can still copy and paste, Researchers have identified an element of the LINE family in parts of the brain that are crucial to the cognitive abilities of these animals.. The discovery, the result of a collaboration between Scuola Internazionale Superiore di Studi Avanzati, Stazione Zoologica Anton Dohrn, and Istituto Italiano di Tecnologia, was made possible by state-of-the-art sequencing techniques used for molecular analysis. Composition of genes active in the nervous system of the octopus.
“The discovery of an element from the LINE family active in the brains of two octopus species, It is very important because it supports the idea that these elements have a specific function that goes beyond copy and paste.”, explains Remo Sanges, director of the SISSA Computational Genomics laboratory. published work, BMC BiologyIt was conducted by an international team of more than twenty researchers from all over the world.
“When I saw, under the microscope, a very strong signal of activity of this element in the vertical lobe, I literally jumped out of my chair, “The structure of the brain in the octopus is the site of learning and cognitive abilities, just like the hippocampus in humans,” explains Giovanna Ponte of Stazione Zoologica Anton Dohrn.
According to Giuseppe Petrosino and Stefano Gustincich of the Istituto Italiano di Tecnologia, “this similarity between human and octopus can be explained as follows, demonstrating the effectiveness of a LINE element at the seat of cognitive abilities: A fascinating example of convergent evolution, a phenomenon in which the same molecular process develops independently in two genetically distant speciesin response to similar needs”.
“The octopus brain is functionally similar to that of mammals in many aspects,” says Graziano Fiorito, director of the Department of Biology and Evolution of Marine Organisms at Stazione Zoologica Anton Dohrn. “The LINE element thus identified represents a very interesting candidate to work with to improve our understanding of the evolution of intelligence.”
Reference work: https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-022-01303-5
……
Environment department contact address:[email protected]