Freiburg researchers use artificial membranes to show how a particular protein reaches the mitochondria
Mitochondria serve as the powerhouses of the cell, converting the energy stored in foods into a form cells can use. When this important task fails, it can result in numerous diseases, particularly those affecting organs with a high energy consumption like the brain or the heart.
The Freiburg biochemistry professor Chris Meisinger, the Freiburg molecular medicine researcher Dr. Nora Vögtle, and the Freiburg pharmaceutical scientists Dr. Martin Holzer and Dr. Michael Keller have discovered a new import pathway proteins use to reach the mitochondria.
The common assumption among researchers up until now has been that proteins are always transported into the mitochondria via so-called import machines. The newly discovered import pathway, by contrast, is independent of the import machines. The research team published the study in the Journal of Cell Biology.
Mitochondria need more than 1000 different proteins to fulfill their vital tasks for the cells. Most of these proteins are produced in the cellular fluid and then imported into the mitochondria. The powerhouses of the cell have import machines in their membranes for this purpose.
These import machines, which are for their part also composed of various proteins, act as gatekeepers and sluices, allowing the mitochondria to import the new proteins they need from the cellular fluid.
The research team found a new import pathway for the protein Ugo1 that does not pass through the import machines. Ugo1 is localized in the outer membrane of mitochondria. The scientists succeeded in reconstructing the protein’s transport pathway in artificial membranes consisting of lipids, fat-like substances present in the membranes of mitochondria.
The import no longer functioned when the researchers constructed the artificial membrane without a particular lipid only present in small amounts, phosphatidic acid. Moreover, the scientists demonstrated that living cells with an elevated concentration of phosphatidic acid also contain a higher amount of Ugo1. “This study shows that contrary to what has previously been assumed, lipids can take on specific and active functions in the import of mitochondrial proteins,” says Chris Meisinger.
Chris Meisinger is a research group leader at the Institute of Biochemistry and Molecular Biology of the University of Freiburg as well as a member of the Freiburg Cluster of Excellence BIOSS Centre for Biological Signalling Studies. Nora Vögtle is a member of Meisinger’s research group. Martin Holzer and Michael Keller conduct research at the Institute of Pharmaceutical Technology and Biopharmacy of the University of Freiburg.
Vögtle, F.N., Keller, M., Taskin, A.A., Horvath, S.E., Guan, X.L., Prinz, C., Opalinska, M., Zorzin, C., van der Laan, M., Wenk, M.R., Schubert, R., Wiedemann, N., Holzer, M., and Meisinger, C. (2015). The fusogenic lipid phosphatidic acid promotes the biogenesis of mitochondrial outer membrane protein Ugo1. Journal of Cell Biology.
Prof. Dr. Chris Meisinger
Institute of Biochemistry and Molecular Biology
University of Freiburg
Phone: +49 (0)761 / 203 - 5287
Rudolf-Werner Dreier | idw - Informationsdienst Wissenschaft
The birth of a new protein
20.10.2017 | University of Arizona
Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research