Using a state-of-the-art technique to map neurons in the spinal cord of a larval zebrafish, Cornell University scientists have found a surprising pattern of activity that regulates the speed of the fish’s movement. The research may have long-term implications for treating injured human spinal cords and Parkinson’s disease, where movements slow down and become erratic.
The study, "A Topographic Map of Recruitment in Spinal Cord," published in the March 1 issue of the journal Nature, maps how neurons in the bottom of the fish’s spinal cord become active during slow movements, while cells further up the spinal cord activate as movements speed up.
By removing specific neurons in the lower spinal cord with laser beams, the researchers rendered the fish incapable of slow movements. By removing nerves further up the backbone, the fish had difficulty moving fast.
"No one had any idea that organization like this existed in a spinal cord," said Joseph Fetcho, a Cornell professor of neurobiology and behavior and an author of the study. "Now that we know the pattern, we can begin to ask how that changes in disease states."
David McLean, Cornell postdoctoral researcher in Fetcho’s laboratory, was the first person to discover the pattern of neural activation and how it was associated with speed of movement. He is the lead author on the study.
The researchers worked with 4 millimeter-long larval zebrafish (Danio rerio) because they are transparent and researchers can see their cells. Fetcho and his colleagues injected the fishes’ spinal cords with a fluorescent dye, which then lit up when calcium ions flooded in as the nerve cells activated. A confocal microscope with lasers allowed the researchers to image the cells at very high resolutions. Using this set up, they watched nerve cells light up as the animals moved at different speeds.
While no one knows how this pattern relates to other vertebrates, the research opens a door toward basic understanding of the architecture and function of nerves in spinal cords. With regard to regeneration of spinal cords following injury, for example, medical researchers need a template for a normal spinal cord in order to know if nerves are re-growing normally, Fetcho said.
In Parkinson’s disease, researchers believe that a neurotransmitter released by brain cells may contribute to activating a system of nerves and muscles that allow for faster movement. They suspect that damage to these brain cells may disrupt the release of dopamine, further complicating free movement. Fetcho and his group are building a transgenic line of fish with those brain cells labeled so they may be targeted and removed with lasers.
Blaine Friedlander | EurekAlert!
Transport of molecular motors into cilia
28.03.2017 | Aarhus University
Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
28.03.2017 | Life Sciences
28.03.2017 | Information Technology
28.03.2017 | Physics and Astronomy