Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How the brain stays receptive: researchers examine the role of channel protein in learning

09.01.2013
PLoS ONE: Pannexin1 is critical for memory and orientation

The channel protein Pannexin1 keeps nerve cells flexible and thus the brain receptive for new knowledge. Together with colleagues from Canada and the U.S., researchers at the Ruhr-Universität Bochum led by the junior professor Dr. Nora Prochnow from the Department of Molecular Brain Research describe these results in PLoS ONE.


Micrograph of the hippocampus: The blue curves show the long-term potentiation in mice with (left) and without Pannexin1 (right). Brains of animals without the channel protein respond especially sensitively to small stimuli, as the big difference between the light and dark blue curve shows. The data is based on original measurements of the study.
Image: Nora Prochnow

In the study, mice comprising no Pannexin1 in memory-related brain structures displayed symptoms similar to autism. Their nerve cells lacked synaptic plasticity, i.e. the ability to form new synaptic contacts or give up old contacts based on the level of usage.

Pannexins are abundant in the central nervous system of vertebrates

Pannexins traverse the cell membrane of vertebrate animals and form large pored channels. They are permeable for certain signalling molecules, such as the energy storage molecule ATP (adenosine triphosphate). The best known representative is Pannexin1, which occurs in abundance in the brain and spinal cord and among others in the hippocampus - a brain structure that is critical for long-term memory. Malfunctions of the pannexins play a role in the development of epilepsy and strokes.

No more scope in long-term potentiation

The research team studied mice in which the gene for Pannexin1 was lacking. Using cell recordings carried out on isolated brain sections, they analysed the long-term potentiation in the hippocampus. Long-term potentiation usually occurs when new memory content is built - the contacts between nerve cells are strengthened; they communicate more effectively with each other. In mice without Pannexin1, the long-term potentiation occurred earlier and was more prolonged than in mice with Pannexin1. “It looks at first glance like a gain in long-term memory”, says Nora Prochnow. “But precise analysis shows that there was no more scope for upward development.” Due to the lack of Pannexin1, the cell communication in general was increased to such an extent that a further increase through the learning of new knowledge was no longer possible. The synaptic plasticity was thus extremely restricted. “The plasticity is essential for learning processes in the brain”, Nora Prochnow explains. “It helps you to organise, keep or even to forget contents in a positive sense, to gain room for new inputs.”

Autistic-like behaviour without Pannexin1

The absence of Pannexin1 also had an impact on behaviour: when solving simple problems, the animals were quickly overwhelmed in terms of content. Their spatial orientation was limited, their attention impaired and an increased probability for seizure generation occurred. “The behavioural patterns are reminiscent of autism. We should therefore consider the Pannexin1 channel more closely with regard to the treatment of such diseases”, says the neurobiologist from Bochum.

Theory: feedback regulation gets out of hand without Pannexin1

According to the scientists’ theory, nerve cells lack a feedback mechanism without Pannexin1. Normally the channel protein releases ATP, which binds to specific receptors and thus reduces the release of the neurotransmitter glutamate. Without Pannexin1 more glutamate is released, which leads to increased long-term potentiation. This causes the cell to lose its dynamic equilibrium, which is needed for an efficient learning process.

Bibliographic record

N. Prochnow, A. Abdulazim, S. Kurtenbach, V. Wildförster, G. Dvoriantchikova , J. Hanske, E. Petrasch-Parwez, V.I. Shestopalov, R. Dermietzel, D. Manahan-Vaughan, G. Zoidl (2012): Pannexin1 stabilizes synaptic plasticity and is needed for learning, PLoS ONE , DOI: 10.1371/journal.pone.0051767

Further information

Prof. Dr. Nora Prochnow, Department of Molecular Brain Research, Faculty of Medicine, 44780 Bochum, Germany, Tel. +49/234/32-24406, E-Mail: Nora.Prochnow@ruhr-uni-bochum.de

Editor: Dr. Julia Weiler

Dr. Josef König | idw
Further information:
http://www.ruhr-uni-bochum.de

More articles from Life Sciences:

nachricht One step closer to reality
20.04.2018 | Max-Planck-Institut für Entwicklungsbiologie

nachricht The dark side of cichlid fish: from cannibal to caregiver
20.04.2018 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>