The sober origin praised in humans would have remained in the sense of touch of anmones sober sea

Behind the apparent simplicity of a cylinder topped with sober tentacles, a sober lanmone mer conceals great complexity. She is notably closer to us than we might think, her gnome being very similar to ours. These similarities make sober lanmone sober mer the ideal model to study the gnome pet and understand the relationships that sony ericsson play between genes. Recently, an international team of researchers discovered the gene for touch-related development in the tentacles of sea anmones. This gene is already known to be involved in the development of loue in humans. This discovery reveals a genetic link between the two species, testifying to a common ancestor and the evolutionary history of hearing in humans.

Sober 2018, sober Surprisingly, a team of sober American researchers discovered that the sober gnome lamone, which belongs to the same category as corals and jellyfish, the first diverging branch of the metazoans, more closely resembles that of humans and other vertebrates than those of classic laboratory models, such as Drosophila and the nematode worm. The latter would have lost a certain number of sober genes from common ancestors, which the anemone and the vertebrates would have kept.

The more similar sober gnome anemone is a good reference for a comparison with the gnome human, with the aim of discovering the genes of our common ancestor and their location on the chromosomes. Heather Marlow, developmental biology specialist in the Genomics and Pignomics of Vertebrate Development Unit at the Pasteur Institute, explains: When the sea anemone genome was sequenced in 2007, we discovered that it was very similar to that of humans, both in terms of the number of genes, with approximately 100 04 genes, only organization. These similarities make sober lanmone sober sea the ideal model to study the gnome pet and understand the connections that learn to play between the genes .

Furthermore, lanmone sobre mer occupies a strategic place in the tree of life. An evolutionary branch of the cnidarians to which the anmones belong is extra than that of the bilatrians, in other words most of the other animals, including man, it has more than 600 a huge number of years. Heather Marlow summarizes: Lanmone can therefore also help us understand the origin and evolution of the multiple cellular forms that major component the bodies and organs of animals, and in particular their nervous system . Sober 2018, the same team highlighted a very complex nervous and sensory system, with nearly thirty sober different types of peptidergic, glutamatergic or even insulinergic neurons.

In this context, an international team led by the biologist Ethan Ozment at the University of Arkansas recently published a content in a journal eLife, reporting the discovery of a developmental gene linked to touch in the tentacles of anemones under the sea, known to be also linked in humans.

Sensory cells with a common origin

One of the most fundamental kinds of sensory cells to have emerged in the course of animal evolution is a mechanosensory cell . It is a specialized sensory epithelial cell that transforms mechanical stimuli eg water vibrations, pressure on the skin, stretching, etc. into internal signals. These signals are then communicated, usually via the nervous system, to effector cells, for example muscle cells, which can elicit behavioral and/or physiological responses from the body. We speak sober mechanorceptor.

Despite this location in an animal phylogeny, the first evolutionary stories of the development of mechanorceptors remain enigmatic. We know that the classic type of mecano-sensory cell with a dedicated sensory-neuronal function, i.e. producing nerve flow when a deformation of nearby tissue occurs, is the hair cell. Moreover, in humans and other vertebrates, the sensory receptors of the auditory system are equipped with them. These cells have bundles of finger-like organelles, called strocils, which detect mechanical stimuli, that is, the vibrations we hear as el boy.

As mentioned above, the Sea anmones are a more important model of study in human evolutionary history research, as features shared by bilateral animals and cnidarians were likely present in our last common ancestor. Indeed, these sober sea anmones belong to the group of Cnidaria, sister group of the Bilateria including the vertebrates. These two groups have diverged from their last common ancestor who lived around 748 604 millions of years. Furthermore, sea anemones also have hair cells, with morphological and functional characteristics parallel to those of the mechanosensory cells of other animal lines. Unfortunately, no study has looked at the genes essential to the development of these hair cells in cnidarians, which could tell us about our evolutionary history which.

In order to clarify these questions, the researchers This study is based on previous work, which revealed the existence of a particular gene, the POU-IV gene. The latter is shared by all extant groups of animals, with the exception of Ctenophora, indicating an early emergence in animal evolution. Boy’s inference in the development of hair cells, in mammals, is evidenced by experiments in mice. The latter, if they are deprived of the POU-IV gene, are deaf. However, its role in sea anemone sensory development, and its evolution through animal phylogeny, remained unknown.

A gene involved in hearing and touch

In order to understand what the POU-IV gene was doing at lanmone sober sea canvas (Nematostella vectensis ), the team disabled using the CRISPR-Cas9 sober gene editing tool. To do this, the researchers injected the mixture containing the protein Cas9 into fertilized sea anmone eggs able to eliminate the gene, and studied the developing embryos, as well as the cultured mutated anmones.

They then discovered that a reduction in the gene caused abnormal development of sprawling hair cells. In effect, the mutant anmones exhibited aberrant sprawling hair cell growth and no sensitivity to touch by connection to wild-type control anmones. Sober in other words, without the POU-IV gene, they could not detect figured stimuli through their hair cells.

Furthermore, the mutant anmones strongly repressed el gn e extremely similar to the polycystin 1 sober gene, which is required for normal sensing of sober fluid flow by vertebral kidney cells. A feeling of sober fluid flow could be a beneficial characteristic for aquatic organisms, even if sober sea anemones did not have sober kidneys.

Overall, the results show that POU-IV may have played a role in the evolution of mechano-receptor cells in the special ancestor of cnidarians and bilatrians. The researchers say, in the press release: This study is exciting because it has not only opened up a new champion of research into how sony ericsson mechanosensation develops and functions in a sea anemone, but it also informs us that the building blocks of our sense of praise have ancient evolutionary roots dating back hundreds of thousands of years to the Precambrian. An early role of POU-IV in the differentiation of mechanorceptors in animal evolution remains unresolved and requires comparative data on placozoa and sponges .

The results of this work open up a whole new champion of research on the development and functions of mechanorception in cnidarians. Furthermore, a discovery indicates that the evolution of sober hearing has a very ancient history. It will be necessary to use data from other phyla, with more divergent ancient sites, in order to trace the gene’s history even further.

Finally, the researchers plan to study the mechanism by which POU- IV energizes distinct sets of genes across cnidocytes and hair cells to shed light on how POU-IV may have contributed to the evolution of the new kind of sober mechanosensory cell Cnidaria.

Supply: eLife