These visual maps consist of millions of nerve cell contacts that need to be wired correctly during development in order for the adult animal to see normally. It is generally thought that the complexity of visual maps, like other brain regions, cannot only be genetically programmed but requires activity by neurons or nerve cells in the brain.
In a new study published in the journal Current Biology, Drs. P. Robin Hiesinger, R. Grace Zhai and co-workers in the laboratory of Dr. Hugo Bellen, director of the Program in Developmental Biology at Baylor College of Medicine, found that this neuronal activity is not required for the formation of the visual map in Drosophila melanogaster, the most common form of fruit fly used in laboratories around the world.
"There is a genetic component (to formation of the vertebrate visual system)," said Bellen, who is also a Howard Hughes Medical Institute investigator. "The neurons in vertebrates are born and are genetically programmed to project into a certain brain region. This is followed by a dynamic phase where neuronal activity refines the visual map. In contrast, in flies the system seems to be completely hard-wired and only rely on genetic inputs."
"The most obvious difference between the insect and vertebrate brain is their size and the number of neurons and connections that need to be made. A possible explanation for the findings is that the fruit fly has many fewer neurons than vertebrates, and the system can therefore just rely on the genetic components in flies," said Bellen.
"In vertebrates, complexity is added because of the challenge of millions of neurons having to make billions of precise connections. You have to work with a gross topological map first, and neuronal activity refines this map later," he said.
The study adds to an ongoing debate about the extent to which brain wiring can be genetically programmed.
"We have to be careful when we interpret these results in light of the complexity of the human brain," said Bellen.
However, he said, "It is astonishing though how only a few thousand genes can program billions of synaptic connections."
Ross Tomlin | EurekAlert!
Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover
First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
17.08.2018 | Physics and Astronomy
17.08.2018 | Information Technology
17.08.2018 | Life Sciences