How do we learn? Why do we develop addictions? Is it possible to shut off an epileptic seizure?
Questions like these might now become easier to address: Scientists at the University Medical Center Hamburg-Eppendorf (UKE) and Humboldt University in Berlin have created a novel molecular switch that could be a valuable new tool for brain research.
The new findings of Prof. Thomas Oertner, Prof. Peter Hegemann and their coworkers have just been published in the journal “Science”.
“We inverted the ion selectivity and turned an excitatory channel into an inhibitory one”, explains Prof. Thomas Oertner, director of the Institute for Synaptic Physiology at the Center for Molecular Neurobiology Hamburg (ZMNH). “We were astounded to discover, that a single point mutation – changing a single letter of the genetic code – could be sufficient to completely invert the sign of current flowing through this channel. We also demonstrated that nerve cells can be selectively switched off with our new tool.”
This finding opens up new possibilities for basic research. Thomas Oertner and his team, for example, are planning to use this tool to investigate emotional aspects of learning. It is also conceivable that this channel could be used to dampen the activity of affected brain regions during epileptic seizures.
From algae to brain research – the emerging field of Optogenetics
Channelrhodopsins are proteins that are activated by light, allowing electrically charged ions to pass through biological membranes. Opening these channels changes the voltage across the membrane. In this way, nerve cells can be tuned on or shut off by light. Channelrhodopsins were discovered in unicellular green algae, which use them to swim towards light.
The biophysicist Prof. Peter Hegemann at Humboldt University in Berlin is credited with the discovery of channelrhodopsin, laying the foundation for the new field of optogenetics. With this latest discovery, optogeneticists have a completely new set of tools at their disposal: One of the new proteins, the chloride-conducting channelrhodopsin with slow kinetics or ‘slow ChloC’, opens its pore and shuts off neurons for several seconds after a short flash instead of needing constant light like the older inhibitory tools. “This means, we now need ten thousand times less light to block neuronal activity”, explains Thomas Oertner.
The research project at the UKE was supported by the German Research Foundation (DFG).
Wietek J, Wiegert JS, Adeishvili N, Schneider F, Watanabe H, Tsunoda SP, Vogt A, Elstner M, Oertner TG, Hegemann P (2014). Conversion of Channelrhodopsin into a light-gated chloride channel. Science, March 27, 2014. http://www.sciencexpress.org
Prof. Dr. Thomas G. Oertner
Institute for Synaptic Physiology
Center for Molecular Neurobiology Hamburg (ZMNH)
University Medical Center Hamburg-Eppendorf (UKE)
Phone: +49 (40) 7410-58228
Christine Trowitzsch | idw - Informationsdienst Wissenschaft
Research team creates new possibilities for medicine and materials sciences
22.01.2018 | Humboldt-Universität zu Berlin
Saarland University bioinformaticians compute gene sequences inherited from each parent
22.01.2018 | Universität des Saarlandes
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
22.01.2018 | Materials Sciences
22.01.2018 | Earth Sciences
22.01.2018 | Life Sciences