Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists zero in on the cellular machinery that enables neurons to fire

19.11.2007
If you ever had a set of Micronauts – toy robots with removable body parts – you probably had fun swapping their heads, imagining how it would affect their behavior. Scientists supported by the National Institutes of Health have been performing similar experiments on ion channels – pores in our nerve cells – to sort out the channels' key functional parts.

In the November 15 issue of Nature, one group of researchers shows that a part of ion channels called the paddle is uniquely transplantable between different channels. Writing in the same issue, another group exploited this property to probe the three-dimensional structure of ion channels on an atomic scale.

"The effects of many toxins and therapeutic drugs, as well as some diseases, can be wholly explained by changes in ion channel function," says Story Landis, Ph.D., director of the National Institute of Neurological Disorders and Stroke (NINDS), part of the NIH. "We also know that ion channels are at least a contributing player in epilepsy, chronic pain, Parkinson's disease and other disorders. As we learn more about how channels work, we're able to pursue more approaches to treatment."

Ion channels are proteins that control the flow of electrically charged salt particles (ions) across the nerve cell membrane. It's the opening and closing of these channels that enables nerve cells to fire off bursts of electrical activity. A built-in voltmeter, called a voltage sensor, pops the channel open when the nerve cell is ready to fire. The papers in Nature hone in on a part of the voltage sensor called the paddle, named for its shape.

In the first study, a team led by NINDS senior investigator Kenton Swartz, Ph.D., shows that the paddle works as a modular unit. Using recombinant DNA technology, they swapped the paddle from an ion channel found in an ancient, volcano-dwelling bacterium to a channel found in rat brain. As long as the paddle was intact, the hybrid channel still worked. This portability could one day be exploited to test potential drugs. For example, researchers who want to target a paddle from a poorly characterized ion channel could stick it into a well-studied channel where the effects of drugs are easier to measure.

Other results in the paper suggest that the paddle itself will be a useful target for new therapeutic drugs. Dr. Swartz's group found that the paddle is the docking site for certain toxins in tarantula venom, which are known to interfere with ion channel opening. There are hints that scorpions, sea anemones and cone snails make similar toxins, Dr. Swartz said. If nature has found ways to manipulate ion channel function, medicinal chemists might be able to do the same, he said.

In the second study, supported by the National Institute of General Medical Sciences (NIGMS), researchers took advantage of the paddle's unique transplantability to create a hybrid ion channel ideal for structural studies. Led by Roderick MacKinnon, M.D. – a Nobel Laureate, an investigator of the Howard Hughes Medical Institute and a biophysicist at Rockefeller University in New York – the team produced data that explain how the voltage sensor is positioned within the membrane and how it triggers channel opening.

"The determination of the three-dimensional structures of ion channels has yielded a framework to understand their fascinating functional properties," says NIGMS director Jeremy M. Berg, Ph.D. "These new results show how clever experimental designs can focus on key questions and steer the direction of additional studies."

Daniel Stimson | EurekAlert!
Further information:
http://www.nih.gov
http://www.ninds.nih.gov

More articles from Interdisciplinary Research:

nachricht OU study expands understanding of bacterial communities for wastewater treatment system
14.05.2019 | University of Oklahoma

nachricht How do muscle and tendon connections last a lifetime? Study in the fruit fly Drosophila
04.04.2019 | Westfälische Wilhelms-Universität Münster

All articles from Interdisciplinary Research >>>

The most recent press releases about innovation >>>

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

Im Focus: Fraunhofer IDMT demonstrates its method for acoustic quality inspection at »Sensor+Test 2019« in Nürnberg

From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.

Reducing machine downtime, manufacturing defects, and excessive scrap

Im Focus: Successfully Tested in Praxis: Bidirectional Sensor Technology Optimizes Laser Material Deposition

The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.

Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...

Im Focus: The hidden structure of the periodic system

The well-known representation of chemical elements is just one example of how objects can be arranged and classified

The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...

Im Focus: MPSD team discovers light-induced ferroelectricity in strontium titanate

Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.

Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...

Im Focus: Determining the Earth’s gravity field more accurately than ever before

Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.

The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

'Sneezing' plants contribute to disease proliferation

24.06.2019 | Agricultural and Forestry Science

Researchers find new mutation in the leptin gene

24.06.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>