Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A question of supplies

07.07.2017

Researchers uncover the fundamental importance of AMPA receptor biogenesis for brain function

For the first time, Dr. Aline Brechet, Dr. Jochen Schwenk and Prof. Dr. Bernd Fakler, together with geneticists from the University of Leipzig and Paris, France, uncovered the significance of the molecular assembly processes – called biogenesis – of AMPA-type glutamate receptors for proper operation of the human brain.


Schematic illustration of AMPA receptor biogenesis in the endoplasmic reticulum (ER) with subsequent delivery to the synaptic compartment. Upper right: pedigree of one of the discovered FRRS1I families.

Graphics: Bernd Fakler

AMPA receptors, the most abundant neurotransmitter receptors in the brain, are multi-protein complexes that are assembled intracellularly and are subsequently transported to the synapses where they are responsible for signal transduction and information processing. Defective receptor assembly resulting from genetic mutations causes severe intellectual disability with cognitive impairment and epileptic activity.

The results introduce an unexpected mechanism for the control of higher brain functions in humans. The biologists and geneticists recently published their findings in the online-journal Nature Communications.

Using high-resolution proteomic analysis, the scientists identified a population of AMPA receptors in brain membrane preparations that fundamentally differs in their subunit composition from synaptic AMPA receptors. These newly identified complexes are restricted to the endoplasmic reticulum and represent a transitional step in the biogenesis of synaptic receptor complexes.

When formation of these transitional complexes is inhibited via virus administered to rodent brain, the number of synaptic AMPA receptors is drastically reduced. As a result, the researchers detected a largely disturbed synaptic signal transduction.

In the human brain, impairment of AMPA receptor biogenesis may be invoked by mutations in the main subunit of the transitional complexes, the so-called FRRS1I protein. The researchers identified there different FRRS1l mutations in three distinct families where homozygously affected patients (mutations in both, maternal and paternal alleles) suffered from severe brain dysfunction: all patients demonstrated largely impaired intellectual abilities, delayed or complete lack of speech development and epileptic activity.

Interestingly, the diseased brains failed to show any significant alterations in morphology. For the scientists, these observations are indicative for functional deficiencies induced by the impaired AMPA receptor biogenesis as the disease-causing mechanism.

As early as 2012 Fakler’s group has shown that AMPA receptors in the brains are assembled from an array of more than 30 different proteins. Quite a number of these proteins - including the FRRS1I protein - lack annotation of primary function(s). With their current work, the scientists have shown how important these ‘unknown’ protein components and research pursuing their molecular mode of action are for understanding higher brain functions.

The physiologists Jochen Schwenk and Bernd Fakler along with the neurobiologist Aline Brechet conduct research at the Institute of Physiology. Schwenk and Fakler also work at the Cluster of Excellence BIOSS Centre for Biological Signalling Studies at the University of Freiburg.

Original publication:
AMPA-receptor specific biogenesis complexes control synaptic transmission and intellectual ability. A. Brechet, R. Buchert, J. Schwenk, S. Boudkkazi, G. Zolles, K. Siquier-Pernet, I. Schaber, W. Bildl, A. Saadi, C. Bole-Feysot, P. Nitschke, A. Reis, H. Sticht, N. Al-Sanna’a, A. Rolfs, A. Kulik, U. Schulte, L. Colleaux, R. Abou Jamra and B. Fakler (2017) Nature Communications 8, 15910; doi: 10.1038/NCOMMS15910

Contact:
Prof. Dr. Bernd Fakler
Institute of Physiology, Department II / BIOSS Centre for Biological Signalling Studies
University of Freiburg
Tel.: 0761/203-5175
E-Mail: bernd.fakler@physiologie.uni-freiburg.de

Weitere Informationen:

https://www.pr.uni-freiburg.de/pm-en/2017/a-question-of-supplies?set_language=en

Rudolf-Werner Dreier | Albert-Ludwigs-Universität Freiburg im Breisgau

More articles from Life Sciences:

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

nachricht Pollen taxi for bacteria
18.07.2018 | Technische Universität München

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

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>