Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Molecular volume control

22.08.2017

About two years ago, scientists from the University of Würzburg discovered that a certain class of receptors is capable of perceiving mechanical stimuli. Now they have begun to unravel the molecular mechanisms behind the discovery.

The receptor studied by scientists from the universities of Würzburg and Leipzig over the past years works similarly to the volume control of a stereo which enhances or attenuates the incoming signal. The receptor in question is called latrophilin/CIRL.


The larval Drosophila chordotonal organ seen under the scanning electron microscope. This sensory functional unit modulates the processing of mechanical stimuli by means of the latrophilin receptor.

(Photo: Scholz et al., 2017)

A little more than two years ago, the researchers had surprised the scientific community by proving that certain receptors, including latrophilin, respond to mechanical stimuli from the environment for example vibration, sound waves or expansion. By doing so, the receptors help organisms to hear, perceive movements and control their own movements.

How the information gets inside the cell

At the time, however, the details of the receptors' contribution were still unclear, i.e. how the process works at the molecular level. In the meantime, the researchers have been able to shed light on some crucial details. They present their results in the current issue of the scientific journal eLife. The lead authors of the study are Dr Robert Kittel, who heads a working group at the Institute of Physiology/Department of Neurophysiology at the University of Würzburg, and Professor Tobias Langenhan, who recently relocated from Würzburg to the University of Leipzig.

"In order for cells to perceive and respond to external stimuli, the information must somehow get inside the cell," Robert Kittel explains the central aspect of the study. This may be accomplished through ion channels where a mechanical stimulus is converted into an electrical response in a very straightforward and fast process.

With the latrophilin receptor things are different: "It does not form a channel and it does not forward the stimulus electrically," Kittel says. Instead, it activates intracellular messengers that trigger special signal cascades inside the cell which ultimately also affect the ion channels. According to Kittel, the receptor thus has a modulating effect on stimulus perception like some kind of volume controller.

Collaboration with numerous experts

The study just published is the result of collaborating with specialists from various domains at the University of Würzburg – an aspect which Robert Kittel particularly appreciates.

One of the contributing experts is the plant physiologist Professor Georg Nagel who was one of the scientists who discovered a celebrated technique which became known as "optogenetics". The underlying principle: Nagel characterizes ion channels and enzymes that can be controlled with light. Robert Kittel and Tobias Langenhan used the larvae of Drosophila, the fruit fly, for their experiments which are almost transparent so that the researchers were able to study the functioning of the receptors with simple flashes of light.

The second expert involved was Professor Markus Sauer, head of the Department of Biotechnology and Biophysics at University of Würzburg's Biocenter. With his team, Sauer developed special forms of high-resolution fluorescence microscopy. This "super resolution" microscopy allows imaging cellular structures and molecules with up to tenfold increased resolution compared to conventional optical microscopes. "By using super-resolution microscopy, we were able to pinpoint the position of the cell membrane where the receptor is located," Robert Kittel says.

Dr. Isabella Maiellaro and Professor Esther Asan are also specialists in the field of imaging procedures. By teaming up with Isabella Maiellaro from the Department of Pharmacology, the researchers were able to directly visualize the intracellular receptor signal. Esther Asan, Professor at the Institute of Anatomy and Cell Biology II at the University of Würzburg, also contributed to the success of the study with her expertise in electron microscopy.

Moreover, the project was supported by the extensive experience of Professor Matthias Pawlak at the Institute of Physiology of the University of Würzburg in the field of sensory physiology and Dr Simone Prömel, a pharmacologist at the University of Leipzig. Robert Kittel sees these collaborations as a good example of how modern biotechnological methods can help answer physiological questions.

A very important molecular family

Latrophilin/CIRL is a member of a family of molecules that has more than 30 members in humans: the so-called adhesion GPCRs, a subgroup of the G protein-coupled receptors (GPCRs). Hundreds of them are encoded in the human genome; their importance is underpinned among others by the fact that around half of all prescription drugs target these receptors and help treat common diseases such as high blood pressure, asthma or Parkinson's.

This shows just how important the research results of the scientists from Würzburg and Leipzig are. After all, knowing what is going on inside the cells is a prerequisite for developing a better understanding of pathological processes and designing new therapies. "The cell biology processes are well conserved in terms of evolution," Robert Kittel says. Similar mechanisms are also at work in human cells.

Robert Kittel and Tobias Langenhan are also members of a research unit funded by Deutsche Forschungsgemeinschaft (DFG FOR 2149) which studies the signalling behaviour of adhesion GPCRs. The current study harnesses the good experimental accessibility of Drosophila to bring new technologies into a biomedical context more quickly. This allows basic molecular mechanisms to be described for the first time. These mechanisms are now to be studied in further organisms and physiological contexts in collaboration with other scientists.

Mechano-dependent signaling by Latrophilin/CIRL quenches cAMP in proprioceptive neurons. Nicole Scholz, Chonglin Guan, Matthias Nieberler, Alexander Grotemeyer, Isabella Maiellaro, Shiqiang Gao, Sebastian Beck, Matthias Pawlak, Markus Sauer, Esther Asan, Sven Rothemund, Jana Winkler, Simone Prömel, Georg Nagel, Tobias Langenhan, Robert J Kittel. eLife 2017;6:e28360. DOI: 10.7554/eLife.28360

Contact

Dr Robert J. Kittel, T: +49 931 31-86046; robert.Kittel@uni-wuerzburg.de

Prof. Tobias Langenhan, T: +49 341 97-22100; tobias.langenhan@uni-leipzig.de

Robert Emmerich | Julius-Maximilians-Universität Würzburg
Further information:
http://www.uni-wuerzburg.de

More articles from Life Sciences:

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

nachricht Pollen taxi for bacteria
18.07.2018 | Technische Universität München

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>