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 An evolutionary heads-up – The brain size advantage
22.05.2015 | Veterinärmedizinische Universität Wien

nachricht Endocrine disrupting chemicals in baby teethers
21.05.2015 | Goethe-Universität Frankfurt am Main

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Basel Physicists Develop Efficient Method of Signal Transmission from Nanocomponents

Physicists have developed an innovative method that could enable the efficient use of nanocomponents in electronic circuits. To achieve this, they have developed a layout in which a nanocomponent is connected to two electrical conductors, which uncouple the electrical signal in a highly efficient manner. The scientists at the Department of Physics and the Swiss Nanoscience Institute at the University of Basel have published their results in the scientific journal “Nature Communications” together with their colleagues from ETH Zurich.

Electronic components are becoming smaller and smaller. Components measuring just a few nanometers – the size of around ten atoms – are already being produced...

Im Focus: IoT-based Advanced Automobile Parking Navigation System

Development and implementation of an advanced automobile parking navigation platform for parking services

To fulfill the requirements of the industry, PolyU researchers developed the Advanced Automobile Parking Navigation Platform, which includes smart devices,...

Im Focus: First electrical car ferry in the world in operation in Norway now

  • Siemens delivers electric propulsion system and charging stations with lithium-ion batteries charged from hydro power
  • Ferry only uses 150 kilowatt hours (kWh) per route and reduces cost of fuel by 60 percent
  • Milestone on the road to operating emission-free ferries

The world's first electrical car and passenger ferry powered by batteries has entered service in Norway. The ferry only uses 150 kWh per route, which...

Im Focus: Into the ice – RV Polarstern opens the arctic season by setting course for Spitsbergen

On Tuesday, 19 May 2015 the research icebreaker Polarstern will leave its home port in Bremerhaven, setting a course for the Arctic. Led by Dr Ilka Peeken from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) a team of 53 researchers from 11 countries will investigate the effects of climate change in the Arctic, from the surface ice floes down to the seafloor.

RV Polarstern will enter the sea-ice zone north of Spitsbergen. Covering two shallow regions on their way to deeper waters, the scientists on board will focus...

Im Focus: Gel filled with nanosponges cleans up MRSA infections

Nanoengineers at the University of California, San Diego developed a gel filled with toxin-absorbing nanosponges that could lead to an effective treatment for skin and wound infections caused by MRSA (methicillin-resistant Staphylococcus aureus), an antibiotic-resistant bacteria. This "nanosponge-hydrogel" minimized the growth of skin lesions on mice infected with MRSA - without the use of antibiotics. The researchers recently published their findings online in Advanced Materials.

To make the nanosponge-hydrogel, the team mixed nanosponges, which are nanoparticles that absorb dangerous toxins produced by MRSA, E. coli and other...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International symposium: trends in spatial analysis and modelling for a more sustainable land use

20.05.2015 | Event News

15th conference of the International Association of Colloid and Interface Scientists

18.05.2015 | Event News

EHFG 2015: Securing health in Europe. Balancing priorities, sharing responsibilities

12.05.2015 | Event News

 
Latest News

Mesoporous Particles for the Development of Drug Delivery System Safe to Human Bodies

22.05.2015 | Materials Sciences

Computing at the Speed of Light

22.05.2015 | Information Technology

Development of Gold Nanoparticles That Control Osteogenic Differentiation of Stem Cells

22.05.2015 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>