Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Synapses – stability in transformation

17.04.2014

Synapses remain stable if their components grow in coordination with each other

Synapses are the points of contact at which information is transmitted between neurons. Without them, we would not be able to form thoughts or remember things. For memories to endure, synapses sometimes have to remain stable for very long periods.


During the learning processes, extensions grow on neurons. Synapses are located at the end of these extensions (left: as seen in nature; right: reconstruction). When the synapse growth is based on the correlated development of all synaptic components, it can remain stable for long periods of time.

© MPI of Neurobiology/ Meyer

But how can a synapse last if its components have to be replaced regularly? Scientists from the Max Planck Institute of Neurobiology in Martinsried near Munich have taken a decisive step towards answering this question. They have succeeded in demonstrating that when a synapse is formed, all of the components must grow in a coordinated way.

This is the only way that a long-term functioning synapse, –the basic prerequisite of learning and memory processes, can be formed. This kind of interactive system must allow for the replacement of individual molecules while the other components stabilise the synapse.

Nothing lasts forever. This principle also applies to the proteins that make up the points of contact between our neurons. It is due to these proteins that the information arriving at a synapse can be transmitted and then received by the next neuron. When we learn something, new synapses are created or existing ones are strengthened. To enable us to retain long-term memories, synapses must remain stable for long periods of time, up to an entire lifetime. Researchers at the Max Planck Institute of Neurobiology in Martinsried near Munich have found an explanation as to how a synapse achieves remaining stable for a long time despite the fact that its proteins must be renewed regularly.

Learning in the laboratory

“We were interested first of all in what happens to the different components of a synapse when it grows during a learning process,” explains study leader Volker Scheuss. An understanding of how the components grow could also provide information about the long-term stability of synapses. Hence, the researchers studied the growth of synapses in tissue culture dishes following exposure to a (learning) stimulus. To do this, they deliberately activated individual synapses using the neurotransmitter glutamate: scientists have long known that glutamate plays an important role in learning processes and stimulates the growth of synapses. Over the following hours, the researchers observed the stimulated synapses and control synapses under a 2-photon microscope. To confirm the observed effects, they then examined individual synapses with the help of an electron microscope. “When you consider that individual synapses are only around one thousandth of a millimetre in size, this was quite a Sisyphean task,” says Tobias Bonhoeffer, the Director of the department where the research was carried out.

Synaptic stability – a concerted effort

The scientists discovered that during synapse growth the different protein structures always grew coordinated with each other. If one structural component was enlarged alone, or in a way that was not correctly correlated with the other components, its structural change would collapse soon after. Synapses with such incomplete changes cannot store any long-term memories.

The study findings show that the order and interaction between synaptic components is finely tuned and correlated. “In a system of this kind, it should be entirely possible to replace individual proteins while the rest of the structure maintains its integrity,” says Scheuss. However, if an entire group of components breaks away, the synapse is destabilised. This is also an important process given that the brain could not function correctly without the capacity to forget things. Hence, the study’s results provide not only important insight into the functioning and structure of synapses, they also establish a basis for a better understanding of memory loss, for example in the case of degenerative brain diseases.

Contact 

Dr. Stefanie Merker

Max Planck Institute of Neurobiology, Martinsried

Phone: +49 89 8578-3514

 

Prof. Dr. Tobias Bonhoeffer

Max Planck Institute of Neurobiology, Martinsried

Phone: +49 89 8578-3751
Fax: +49 89 8578-2481

Email:tobias.bonhoeffer@neuro.mpg.de

Dr. Volker Scheuss

Original publication

 
Daniel Meyer, Tobias Bonhoeffer, Volker Scheuss
Balance and stability of synaptic structures during synaptic plasticity
Neuron, 16 April 2014

Dr. Stefanie Merker | Max-Planck-Institute

Further reports about: Learning Neurobiology Phone glutamate long-term memories neurons proteins synapses synaptic

More articles from Life Sciences:

nachricht A Fluttering Accordion
04.08.2015 | Friedrich-Schiller-Universität Jena

nachricht Molecular Spies to Fight Cancer - Procedure for improving tumor diagnosis successfully tested
03.08.2015 | Helmholtz-Zentrum Dresden-Rossendorf

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Greenhouse gases' millennia-long ocean legacy

Continuing current carbon dioxide (CO2) emission trends throughout this century and beyond would leave a legacy of heat and acidity in the deep ocean. These...

Im Focus: Glaciers melt faster than ever

Glacier decline in the first decade of the 21st century has reached a historical record, since the onset of direct observations. Glacier melt is a global phenomenon and will continue even without further climate change. This is shown in the latest study by the World Glacier Monitoring Service under the lead of the University of Zurich, Switzerland.

The World Glacier Monitoring Service, domiciled at the University of Zurich, has compiled worldwide data on glacier changes for more than 120 years. Together...

Im Focus: Quantum Matter Stuck in Unrest

Using ultracold atoms trapped in light crystals, scientists from the MPQ, LMU, and the Weizmann Institute observe a novel state of matter that never thermalizes.

What happens if one mixes cold and hot water? After some initial dynamics, one is left with lukewarm water—the system has thermalized to a new thermal...

Im Focus: On the crest of the wave: Electronics on a time scale shorter than a cycle of light

Physicists from Regensburg and Marburg, Germany have succeeded in taking a slow-motion movie of speeding electrons in a solid driven by a strong light wave. In the process, they have unraveled a novel quantum phenomenon, which will be reported in the forthcoming edition of Nature.

The advent of ever faster electronics featuring clock rates up to the multiple-gigahertz range has revolutionized our day-to-day life. Researchers and...

Im Focus: Superfast fluorescence sets new speed record

Plasmonic device has speed and efficiency to serve optical computers

Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second and could form the basis of optical computing.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Success 4.0 – Is Your Company Fit for the Future? New Series of Events for Executives

04.08.2015 | Event News

3rd Euro Bio-inspired - International Conference and Exhibition on Bio-inspired Materials

23.07.2015 | Event News

Clash of Realities – International Conference on the Art, Technology and Theory of Digital Games

10.07.2015 | Event News

 
Latest News

Small tilt in magnets makes them viable memory chips

04.08.2015 | Information Technology

New Design Brings World’s First Solar Battery to Performance Milestone

04.08.2015 | Power and Electrical Engineering

Magnetism at Nanoscale

04.08.2015 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>