Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The Dance of the Chaperones - Max Planck Scientists Identify Key Player of Protein Folding

08.03.2012
Proteins are the molecular building blocks and machinery of cells, and are involved in practically all biological processes.

To fulfill their tasks they need to be folded into a complicated three-dimensional structure. Scientists from the Max Planck Institute of Biochemistry (MPIB) in Martinsried near Munich, Germany, have now analyzed one of the key players of the folding process: the molecular chaperone DnaK.


The chaperone DnaK binds to new proteins and mediates their folding. Proteins it cannot fold, DnaK transports to GroEL, a highly specialized folding machine. Grafic: F.-Ulrich Hartl / Copyright: MPI of Biochemistry

“The understanding of these mechanisms is of great interest in the light of the many diseases in which folding goes awry, such as Alzheimer’ or Parkinson’s” says Ulrich Hartl, MPIB director. Their work has now been published in Cell Reports.

Proteins are responsible for almost all biological functions. The cells of the human body continuously synthesize thousands of different proteins in the form of amino acid chains. In order to be biologically useful, these chains must fold into a complex three-dimensional pattern. When this difficult process goes wrong, it can lead to useless or even dangerous protein clumps. All cells, from bacteria to human, have therefore developed a network of molecular chaperones, themselves proteins, which help other proteins to fold properly.

MPIB scientists have now investigated the organization of this network in the bacterium Escherichia coli. Using proteomic analyses they show how different chaperones cooperate during the folding process. “We identified the Hsp70 protein DnaK as the central player of the network,” explains Ulrich Hartl. “It functions as a kind of turntable.” DnaK binds to about 700 different protein chains as they are synthesized. Furthermore, DnaK mediates the folding of most of these protein chains. Those it cannot fold are transferred to yet another chaperone, the barrel-shaped GroEL. GroEL is a highly specialized folding machine. It forms a nano-cage in which a single protein chain is temporarily enclosed and allowed to fold while protected from external influences.

Disruptions in the Chaperone Network
The researchers also investigated what happens when the chaperone network is disturbed. For example, when GroEL is removed from the cells, its client proteins accumulate on DnaK, which then shuttles them to proteases to be decomposed. “Apparently, DnaK realizes that the attached protein chains will never be able to mature into useful molecules,” says the biochemist. Similar but even more complicated chaperone networks control the proteome of human cells. Understanding these reactions is of great interest in the light of the many neurodegenerative diseases in which folding goes awry.
Original Publications:
G. Calloni, T. Chen, S.M. Schermann, H. Chang, P. Genevaux, F. Agostini, G.G. Tartaglia, M. Hayer-Hartl and F.U. Hartl: DnaK Functions as a Central Hub in the E. coli Chaperone Network. Cell Reports, March 8, 2012
DOI: 10.1016/j.celrep.2011.12.007

Contact:

Prof. Dr. F.-Ulrich Hartl
Cellular Biochemistry
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried
E-Mail: uhartl@biochem.mpg.de

Anja Konschak
Public Relations
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried
Phone ++49/89-8578-2824
E-mail: konschak@biochem.mpg.de

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

More articles from Life Sciences:

nachricht Biophysicists reveal how optogenetic tool works
29.05.2020 | Moscow Institute of Physics and Technology

nachricht Mapping immune cells in brain tumors
29.05.2020 | University of Zurich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Biotechnology: Triggered by light, a novel way to switch on an enzyme

In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".

Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...

Im Focus: New double-contrast technique picks up small tumors on MRI

Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The work is published May 25 in the journal Nature Nanotechnology.

researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from...

Im Focus: I-call - When microimplants communicate with each other / Innovation driver digitization - "Smart Health“

Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.

When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...

Im Focus: When predictions of theoretical chemists become reality

Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.

Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...

Im Focus: Rolling into the deep

Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.

A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

Black nitrogen: Bayreuth researchers discover new high-pressure material and solve a puzzle of the periodic table

29.05.2020 | Materials Sciences

Argonne researchers create active material out of microscopic spinning particles

29.05.2020 | Materials Sciences

Smart windows that self-illuminate on rainy days

29.05.2020 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>