Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Insights into the structure of a protein transport assistant

15.01.2014
Proteins are the molecular building blocks and machines of the cell and are involved in virtually every process of life.

After protein production, many proteins are equipped with attachments such as sugar residues in order to perform their tasks properly. This process is directly coupled to the transport across a membrane.


Many protein complexes are involved in protein synthesis.Through the ER translocon (green, blue and red) the newly synthesized protein is transported across the membrane (gray).

Graphic: Friedrich Förster / Copyright: MPI of Biochemistry

Employing various methods of structural biology, scientists at the Max Planck Institute (MPI) of Biochemistry in Martinsried near Munich, Germany, have now gained insights into the architecture of the protein complex (ER translocon) responsible for this process. The results of the joint project have now been published in Nature Communications.

Producing a protein is a highly intricate process for the cell and involves many individual steps. Depending on the purpose for which a protein is used, there are different sites for protein production: the cytoplasm or the endoplasmic reticulum (ER). The ER is separated by a membrane from its surroundings in the cytoplasm. Even before protein synthesis is completed, the proteins produced at the ER enter via its membrane into the interior of the ER and are modified through the attachment of sugar residues concomitantly. Without these attachments, the proteins would not be able to fold properly and thus would not fulfill their functions in the cell.

Scientists of the research group “Modeling of Protein Complexes” have now described the architecture of the protein complex responsible for the transport and modification of the newly produced protein: the ER translocon. “It is located in the membrane of the ER, and this fact, together with its size and complex composition, has greatly hampered previous structural studies,” says Friedrich Förster, group leader at the MPI of Biochemistry, describing the initial situation. The structures of many subunits and their arrangement in the native ER translocon have thus far remained elusive.

It was not until cryoelectron tomography came into use that researchers could gain first insight into the architecture of the translocon. The sample is “shock frozen” to preserve its natural structure. Using an electron microscope, the scientists capture two-dimensional images of the object from different perspectives, from which they then reconstruct a three-dimensional image. Further investigations have made it possible to identify individual modules in the structure. Among them is the module that attaches the sugar residues to the newly produced protein.

“Based on this method, we will now try to determine the structure and location of other components of the ER translocon," says Förster. If the researchers know the individual structures of the ER translocon and their arrangement in the complex, they can indirectly draw conclusions about the precise functions and interactions of all components.

Original publication
Pfeffer, S., Dudek, J., Gogala, M., Schorr, S., Linxweiler, J., Lang, S., Becker, T., Beckmann, R., Zimmermann, R., Förster, F.: Structure of the mammalian oligosaccharyl-transferase complex in the native ER protein translocon. Nature Commun, January 10, 2014

Doi: 10.1038/ncomms4072 (2013).

Contact
Dr. Friedrich Förster
Modeling of Protein Complexes
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried
Germany
Email: foerster@biochem.mpg.de
http://www.biochem.mpg.de/foerster
Anja Konschak
Public Relations
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried
Germany
Tel. +49 89 8578-2824
E-Mail: konschak@biochem.mpg.de
http://www.biochem.mpg.de
Weitere Informationen:
http://www.biochem.mpg.de/foerster
- website of the research group "Modeling of Protein Complexes" (Friedrich Förster)
http://www.biochem.mpg.de/3686257/071_foerster_translocon_nature
- complete press release

Anja Konschak | Max-Planck-Institut
Further information:
http://www.biochem.mpg.de

More articles from Life Sciences:

nachricht Fish Oil-Diet Benefits May be Mediated by Gut Microbes
28.08.2015 | University of Gothenburg

nachricht Bio-fabrication of Artificial Blood Vessels with Laser Light
28.08.2015 | Fraunhofer-Institut für Lasertechnik ILT

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

Im Focus: Self-healing landscape: landslides after earthquake

In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.

These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...

Im Focus: FIC Proteins Send Bacteria Into Hibernation

Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.

For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...

Im Focus: Fraunhofer IPA develops prototype of intelligent care cart

It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.

Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Interstellar seeds could create oases of life

28.08.2015 | Physics and Astronomy

An ounce of prevention: Research advances on 'scourge' of transplant wards

28.08.2015 | Health and Medicine

Fish Oil-Diet Benefits May be Mediated by Gut Microbes

28.08.2015 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>