Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers uncover steps in synapse building, pruning

17.11.2011
Like a gardener who stakes some plants and weeds out others, the brain is constantly building networks of synapses, while pruning out redundant or unneeded synapses. Researchers at The Jackson Laboratory led by Assistant Professor Zhong-wei Zhang, Ph.D., have discovered a factor in synapse-building, also showing that the building and pruning processes occur independent of each other.

Mammals are born with functioning but not-yet-developed brains. After birth, external stimuli and internal programs continue to shape the connections between neurons, known as synapses, and the formation of networks of synapses known as neuronal circuits.

Some grow stronger, some grow weaker, redundant connections are eliminated, and so on. Such "plasticity," the ongoing refinement of neural connections and networks, continues throughout life, albeit more subtly with time and maturation.

Much about plasticity remains unknown. How the neural circuits are modified, what controls the modification, the mechanics of strengthening or eliminating specific synapses and much more are subjects of ongoing research. Besides gaining a better picture of normal brain development, scientists seek to understand the errors in synapse building and pruning that are associated with autism, mental retardation and schizophrenia.

Zhang and colleagues investigated a major type of synapse in the brain (called the glutamatergic synapse) that undergoes rapid refinement soon after birth. What they discovered is that these synapses are strengthened through the addition of a particular kind of glutamate receptors, beginning about a week after birth for mice. Notably, sensory deprivation disrupts the strengthening of the synapses, highlighting the role of early experience in synapse building.

In a somewhat surprising finding, the Zhang lab also discovered that the elimination of redundant synapses was not dependent on the other synapses' being strengthened. Since synaptic strengthening usually precedes removal of redundant synapses, it was not known if such elimination is dependent on the prior strengthening. In mice lacking the receptor, which prevented significant strengthening of synaptic connections, redundant synapses were eliminated as usual.

The Jackson Laboratory is an independent, nonprofit biomedical research institution and National Cancer Institute-designated Cancer Center based in Bar Harbor, Maine, with a facility in Sacramento, Calif., a planned facility in Farmington, Conn., and a total staff of about 1,400. Its mission is to discover the genetic basis for preventing, treating and curing human disease, and to enable research and education for the global biomedical community.

Wang et al.: Elimination of redundant synaptic inputs in the absence of synaptic strengthening. Journal of Neuroscience, Nov. 16, 2011, DOI:10.1523/JNEUROSCI.4569-11.2011

Joyce Peterson | EurekAlert!
Further information:
http://www.jax.org

More articles from Life Sciences:

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Global study of world's beaches shows threat to protected areas

19.07.2018 | Earth Sciences

New creepy, crawly search and rescue robot developed at Ben-Gurion U

19.07.2018 | Power and Electrical Engineering

Metal too 'gummy' to cut? Draw on it with a Sharpie or glue stick, science says

19.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>