Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


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

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:

More articles from Interdisciplinary Research:

nachricht Lego-like wall produces acoustic holograms
17.10.2016 | Duke University

nachricht New evidence on terrestrial and oceanic responses to climate change over last millennium
11.10.2016 | University of Granada

All articles from Interdisciplinary Research >>>

The most recent press releases about innovation >>>

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

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>