International team decodes patterns of ion channel activity using novel stochastic approach
Scientists from the universities of Melbourne and Göttingen have gained new insights into the complex stochastic patterns of opening and closing observed in ion channels. The key is the molecular architecture of the protein that ion channels are made of.
Proteins can rearrange their three-dimensional structure only in certain ways. By analysing a large set of time series data, the researchers were able to link the activity levels of an ion channel to the configurations of the channel protein. The study was published in the journal Proceedings of the Royal Society A.
Ion channels are tiny components of human cells that play important roles in all physiological processes occurring in the body. They form pores that allow electrically charged particles (ions) such as sodium, chloride and potassium to pass the cell membrane.
Through ion channels, nerve cells are charged like batteries, which allows them to communicate with other cells, for example, in the brain. The heartbeat is also initiated once per second by such an electrical signal. Defects or missing of certain ion channels can lead to diseases such as cystic fibrosis.
Via transforming their structure, ion channels open or close pores in the cell membrane. However, this opening and closing can be quite irregular.
“Quite often, an ion channel doesn’t seem to do anything for a long time. But then it suddenly shows its maximum level of activity before it switches off again”, explains Dr. Ivo Siekmann from Göttingen University’s Felix Bernstein Institute for Mathematical Statistics. “And in between there can be further intermediate activity levels.”
The key is the complex three-dimensional protein structure that forms the ion channel. “An ion channel can’t deform arbitrarily”, says Dr. Siekmann. “Similar to yoga, there are certain positions that work for an ion channel.” The activity levels of the ion channels correspond to different yoga poses. By combining several novel statistical and mathematical approaches, the scientists revealed how an ion channel transitions between these different yoga poses.
The study has several practical implications: Whereas designing pharmaceuticals that target ion channels has the potential to develop highly specific drugs, the results of the article indicate that only the average activity level, but not the actual opening and closing of the ion channel can be influenced.
“Switching between different activity levels provides a simpler explanation for some physiological processes”, says Dr. Siekmann. “Instead of the complicated and hectic opening and closing, they depend on the relaxed transitions between different yoga poses.”
Dr. Ivo Siekmann is a postdoc at the Felix Bernstein Institute for Mathematical Statistics (FBMS) in the Faculty of Mathematics and Computer Science at the University of Göttingen. He works in Prof. Dr. Axel Munk’s group, which develops statistical models and methods for the analysis of ion channels.
This research is funded through the DFG Collaborative Research Centre “Functionality controlled by organization in and between membranes“ and a Max Planck Fellowship at the Max Planck Institute for Biophysical Chemistry in Göttingen.
Original publication: Ivo Siekmann et al. Modelling modal gating of ion channels with hierarchical Markov models. Proceedings of the Royal Society A 2016. Doi: 10.1098/rspa.2016.0122.
Dr. Ivo Siekmann
University of Göttingen
Faculty of Mathematics and Computer Science
Institute for Mathematical Stochastics
Goldschmidtstraße 7, 37077 Göttingen
Phone +49 551 39-172127
Thomas Richter | Georg-August-Universität Göttingen
The irresistible fragrance of dying vinegar flies
16.08.2017 | Max-Planck-Institut für chemische Ökologie
How protein islands form
15.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).
The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
16.08.2017 | Physics and Astronomy
16.08.2017 | Materials Sciences
16.08.2017 | Interdisciplinary Research