HZI scientists develop model for dynamic mitochondrial networks
Mitochondria are the power plants of cells. They control the production of energy and initiate various central cellular processes. If they become non-functional, this can cause or favour a number of diseases. These diseases are mainly of a neurological or muscular type, but include ageing processes as well.
Systems biologists at the Helmholtz Centre for Infection Research (HZI) in Braunschweig used a new mathematical model to describe which mechanisms are involved in the formation and maintenance of the dynamic mitochondrial networks in cells. The scientists published their results in "Scientific Reports".
One special feature of mitochondria is their pronounced dynamic behaviour inside the cell. They form a network that changes on a time scale of minutes through fission and fusion with other mitochondria again. Their special structure has a significant influence on how effectively they can supply energy:
Fibrous network structures produce a large amount of energy, whereas smaller fragments are less effective. "These processes play a role in cell ageing as well. Over-stressed or damaged mitochondria get fragmented and are then subjected to disposal," says Valerii Sukhorukov, who is a scientist at the Systems Immunology department at the HZI and the principal author of the study.
But how does the dynamic balance between the small fragments and the effective fibres of mitochondria get established? This was the central question addressed by the researchers. "Mechanisms of this type cannot be studied by biochemical analyses alone. This requires model-based simulations on a computer that explain the dynamic changes in the cell very well," says Prof Michael Meyer-Hermann, who directs the Systems Immunology department.
For this purpose, the scientists developed an initial mathematical model that is based on the different lengths of the mitochondrial fragments in linear or branched arrangement. The central result of the study is that an exact description of the mitochondria in the cell becomes possible only if the random motions of mitochondria along the fibres of the cellular skeleton, called microtubules, are taken into account.
This resulted in a so-called graph model that is based on the density of the microtubules and their intersections within the cell. The model describes all forms of mitochondria that have been found in experiments thus far and it also yields explanations for events that were understood incompletely thus far.
Sukhorukov and his colleagues would like to use the new mathematical model in the future to analyse the quality control of the fragmented mitochondria and to understand how cells control or remedy damage to their mitochondria. "This is very important to understand how cells control their energy balance despite the accumulation of damage with advancing age. This would allow us to draw conclusions about certain genetics-related diseases such as Parkinson's and ageing processes in the immune system," says Sukhorukov.
Valerii M. Sukhorukov, Michael Meyer-Hermann. Structural Heterogeneity of the Mitochondria Induced by the Microtubule Cytoskeleton.Scientific Reports. 2015 Sep 11. 5:13924. DOI: 10.1038/srep13924
http://www.helmholtz-hzi.de/en/news_events/news/view/article/complete/how_the_po... - This press release at helmholtz-hzi.de
http://dx.doi.org/10.1038/srep13924 - Link to the original publication
Susanne Thiele | Helmholtz-Zentrum für Infektionsforschung
Seeing on the Quick: New Insights into Active Vision in the Brain
15.08.2018 | Eberhard Karls Universität Tübingen
New Approach to Treating Chronic Itch
15.08.2018 | Universität Zürich
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
15.08.2018 | Physics and Astronomy
15.08.2018 | Earth Sciences
15.08.2018 | Physics and Astronomy