Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Human protein factories in 3D - Insights into the interior of human cells at the nano level

10.09.2010
Due to cell-biological research, it is already known which components of the cell are responsible for the production of proteins. But so far it has not been explored in detail how these protein factories (ribosomes) are organized inside the cell.

Recently, scientists at the Max Planck Institute of Biochemistry (MPIB) in Martinsried near Munich, Germany, succeeded in mapping the inner life of an intact human cell three-dimensionally via cryo-electron tomography. In this way they were able to show where the ribosomes are located in the cell and how they are arranged. In the past, this was only possible with bacterial cells. The results have now been published in Molecular Cell.

Human cells are very complex entities with many different components. A very important cellular component are the ribosomes: As the protein factories of the cell, they are responsible for the production of proteins (protein synthesis). The blueprint provides our heritable information, the DNA.

Because of their importance for protein synthesis, the ribosomes have often been subject of structural research. Until now, the scientists could only look at individual, isolated ribosomes. But in the living cell, ribosomes usually appear lined up like pearls on a string, in so-called polyribosomes. An isolated view is not enough to understand completely how the protein production proceeds inside the cell and how it is embedded in the complex cellular structures and processes. Thus it is necessary to map and to investigate the ribosomes in their “natural environment”, in the interior of the cell. This permits cryo-electron tomography.

With this method, which was mainly developed in the department of Molecular Structural Biology, headed by Wolfgang Baumeister, three-dimensional cellular structures can be mapped and examined. The cell is sort of quick-frozen, so that its spatial structure remains and its properties are not modified. Then the scientists use the electron microscope to record twodimensional pictures of the cell from different perspectives. From these pictures they finally reconstruct a three-dimensional image. By using this method, the MPIB scientists were able to create a three-dimensional map of an intact human cell for the first time. This is the continuation of former work, when the team around Wolfgang Baumeister and F.-Ulrich Hartl already managed to analyze the spatial arrangement of polyribosomes in the bacterium E. coli (Brandt et al., Cell 2009) and of inactivated ribosomes in a whole E. coli cell (Ortiz et al., JCB

2010).

Now the scientists discovered how the ribosomes are positioned inside the human cell: Their arrangement is clearly non-random but rather makes sure that newly originated, still unfolded proteins keep a big distance between each other. “We could already observe a similar positioning in bacterial cells which suggests that the ribosomes of all human beings are arranged in almost the same manner”, explains Florian Brandt, scientist at the MPIB. “This spatial organization of the ribosomes could probably have the aim to inhibit the aggregation and misfolding of newly originated proteins.”

The work of the MPIB scientists is another important step for cell biology, because it helps to better understand the distribution of cellular components and the spatial organization of the whole cell much better. “In the future it could also be interesting”, says Brandt, “how the organization of ribosomes changes in aging and sick cells and how these changes affect the total efficiency of protein production and folding.” [UD]

Original Publication:
Florian Brandt, Lars-Anders Carlson, F.-Ulrich Hartl, Wolfgang Baumeister and Kay Grünewald: The three-dimensional organization of polyribosomes in intact human cells. Molecular Cell, August 27, 2010.
Contact:
Prof. Dr. Wolfgang Baumeister
Molecular Structural Biology
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried, Germany
E-mail: baumeist@biochem.mpg.de
Dr. Kay Grünewald
The Division of Structural Biology
University of Oxford
The Henry Wellcome Building for Genomic Medicine
Roosevelt Drive
Oxford, OX3 7BN
United Kingdom
E-mail: kay@strubi.ox.ac.uk
Anja Konschak
Public Relations
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried, Germany
Phone ++49/89-8578-2824
E-mail: konschak@biochem.mpg.de

Anja Konschak | idw
Further information:
http://www.biochem.mpg.de/en/news/index.html
http://www.biochem.mpg.de/en/rd/baumeister/index.html
http://www.biochem.mpg.de

More articles from Life Sciences:

nachricht Scientists spin artificial silk from whey protein
24.01.2017 | Deutsches Elektronen-Synchrotron DESY

nachricht Choreographing the microRNA-target dance
24.01.2017 | UT Southwestern Medical Center

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists spin artificial silk from whey protein

X-ray study throws light on key process for production

A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Breaking the optical bandwidth record of stable pulsed lasers

24.01.2017 | Physics and Astronomy

Choreographing the microRNA-target dance

24.01.2017 | Life Sciences

Spanish scientists create a 3-D bioprinter to print human skin

24.01.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>