Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New operating principle of potassium channels discovered

28.01.2014
Neurons transmit information with the help of special channels that allow the passage of potassium ions. Defective potassium channels play a role in epilepsy and depression.

The scientists working with Prof. Henning Stahlberg at the Biozentrum of the University of Basel have now identified the complete 3D structure of a particular potassium channel, a HCN channel.


3D model of several HCN potassium channels arranged side by side.
University of Basel

This enabled them to draw conclusions about its mechanism of action, which they describe in the current issue of “Nature Communications”.

Neurons conduct information by way of electrical impulses through our body. Potassium channels are a key component of this electrical circuit and are controlled either by an electrical impulse or through signaling molecules. In man, the dysfunction of the so-called HCN potassium channels is associated with neurological disorders such as epilepsy and depression. Prof. Henning Stahlberg’s team at the Biozentrum of the University of Basel has now elucidated the full structure of a bacterial counterpart of this type of potassium channel, which has provided new insights into its functioning.

New operating principle thanks to the 3D structure
Potassium channels are embedded in the membrane of cells. They form a pore with a filter that selectively allows the passage of potassium ions, and which is controlled by the signaling molecule cAMP. It was previously assumed that the pore could open and close, thus regulating the flow of potassium ions. Stahlberg’s team has now, however, found indications for another mode of action. Employing crystallization technology and electron microscopy, the scientists have reconstructed the intact three dimensional structure of the bacterial channel in its natural environment in both the presence and absence of cAMP.

Based on the analysis of these structures, they discovered, contrary to popular belief, that the pore always remains open. “When the signaling molecule cAMP docks onto the potassium channel, it causes a rearrangement and shift in the protein scaffold,” explains Julia Kowal, first author of this study. “We think that cAMP in fact widens the filter somewhat, thereby controlling the flow of potassium ions.” The newly uncovered structural details have made it possible for the researchers to consider the mode of functioning of these channels from a new perspective.

Mechanism relevant for new drugs
Stahlberg would like to investigate the filter region more closely with an extremely high resolution camera, in order to resolve the last remaining questions about this mechanism. These signal-driven potassium channels are also referred to as “pacemaker channels”. They help to generate the rhythm of the heart as well as the rhythmic excitability of neurons. The precise understanding of the mode of action is thus the basis for developing specific drugs for the treatment of epilepsy and cardiac arrhythmias.
Original Citation
Julia Kowal, Mohamed Chami, Paul Baumgartner, Marcel Arheit, Po-Lin Chiu, Martina Rangl, Simon Scheuring, Gunnar F. Schröder, Crina M. Nimigean, and Henning Stahlberg
Ligand-induced structural changes in the cyclic nucleotide-modulated potassium channel MloK1.
Nature Communications, Published Online 28 January 2014
DOI: 10.1038/ncomms4106
Further Information
Prof. Henning Stahlberg, Biozentrum, University of Basel at the Department for Biosystems Science and Engineering (D-BSSE), Tel.: +41 61 387 32 62, E-mail: henning.stahlberg@unibas.ch

Katrin Bühler | Universität Basel
Further information:
http://www.unibas.ch

More articles from Life Sciences:

nachricht Chains of nanogold – forged with atomic precision
23.09.2016 | Suomen Akatemia (Academy of Finland)

nachricht Self-assembled nanostructures hit their target
23.09.2016 | King Abdullah University of Science and Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

Im Focus: Launch of New Industry Working Group for Process Control in Laser Material Processing

At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.

In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...

Im Focus: New laser joining technologies at ‘K 2016’ trade fair

Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.

K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

ICPE in Graz for the seventh time

20.09.2016 | Event News

Using mathematical models to understand our brain

16.09.2016 | Event News

 
Latest News

Chains of nanogold – forged with atomic precision

23.09.2016 | Life Sciences

New leukemia treatment offers hope

23.09.2016 | Health and Medicine

Self-assembled nanostructures hit their target

23.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>