This new study helps to understand how horizontal is created in other nerve circuits, such as those that facilitate coordination of movements between the two sides of the body
A group of researchers from the UMH-CSIC Neuroscience Institute, in Alicante, led by Dr Eloísa Herrera, discovered a genetic software necessary to form binary circuits, such as those that enable 3D vision or an enabling drive. Coordinate. The discovery, made in mice, was published today at Science Advances.
Not only does this new study explain how to transfer images from the retina to the brain for 3D vision, but it also helps us understand how crosshairs are created in other neural circuits, such as those that allow us to coordinate movements in both. Aspects of the body, Dr. Herrera explains.
The work also reveals the important role of a protein known as Zic2 in regulating a signaling pathway called Wnt, which is essential for the correct development of the embryo and is highly conserved between species, from fruit flies to humans, including mice, in this study.
This pathway is altered usually in pathological scenarios such as spina bifida or other disorders associated with incomplete closure of the neural tube as well as in several types of cancer. New details illustrated in this work on regulating this pathway through Zic2 will help us understand the origin of this type of disease in order to try to prevent its emergence.
The ability to perceive the three-dimensional world and respond appropriately to external stimuli largely depends on a type of neural circuit known as a binary that connects the two cerebral hemispheres and is essential for many of the tasks we perform daily.
These binary circuits require the crossing of one portion of the nerve fibers to the corresponding hemisphere from which they originate and the other hemisphere permanently in the original hemisphere. “The genetic program that we have identified ensures that a portion of the neurons in the retina carries visual information to the corresponding cerebral hemisphere, and the action of a protein called Zic2 stops this program in another group of retinal neurons so that the visual signal can also be shown,” explains Eloissa Herrera. To the same hemisphere. ”
Years ago, Dr. Eloísa Herrera’s group discovered that Zic2 makes duality possible by ensuring that a portion of neuronal extensions (axons) remain in the same hemisphere from which they originate. And in this new work, they describe that to ensure the hubs remain in the same hemisphere, Zic2 has stopped the genetic program that causes them to cross into the opposite hemisphere.
“This discovery allowed us to identify the corresponding program and noticed that it shares common elements with a well-known signaling pathway, called Wnt, which is also involved in many other processes of embryonic development.” Eloísa Herrera also highlights the group “development and assembly of binary circuits in the device.” Neuropsychiatry “at the UMH-CSIC Neuroscience Institute in Alicante.
The discovery was made in the visual pathway of mice, which is similar to the optical pathway of other mammals, including our species. Each of the two optic nerves that connect the retina to the brain is made up of many nerve fibers. The optic nerves converge in an X-shaped structure, called the optic cross, which is located at the base of the brain. Here the information crosses between the two cerebral hemispheres, which makes vision possible in a three-dimensional image.
“Each eye sends visual information to both sides of the brain because about half of the axons of the neurons in the retina cross the mid-brain line to connect with the opposite hemisphere, while the other hemisphere avoids this crossing to project into the brain hemisphere on the same side they came from. This allows for anatomical organization. For the brain to combine the slightly different images it receives from each eye to create a three-dimensional sensation, ”Dr. Herrera explains.
It is precisely on the optical cross that Zic2 acts as a switch to stop the genetic program that allows axons to pass to the other hemisphere. This “switching on the path” is essential for the brain to create a 3D image from two flat images coming from the retina.