Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

What Holds Chromosomes Together - Max Planck Scientists Elucidate Operating Mode of DNA-Packaging

26.05.2015

All living organisms consist of cells that have arisen from other living cells by the process of cell division. In order to ensure that the genetic material is equally and accurately distributed between the two daughter cells during cell division, the DNA fibers must remain in an orderly and closely-packed condition.

At the Max Planck Institute (MPI) of Biochemistry in Martinsried near Munich, scientists have now elucidated how this packaging process works in bacteria. Their studies showed that the SMC protein complex holds DNA together like a clip and thus keeps the genetic material in order.


The SMC protein complex (green, blue, orange) embraces the DNA like a clip and thus, keeps the genetic material in order.

Larissa Wilhelm / Copyright: MPI of Biochemistry

In each human cell, about two meters of DNA must fit into a cell nucleus that has a diameter of only a few thousandths of a millimeter. Here, the DNA is organized in individual chromosomes. In order to ensure the DNA’s secure transport during cell division, the long and coiled DNA fibers must be tightly packed.

So far, scientists have only a sketchy understanding of this step: The SMC protein complexes play a key role in this process. They consist of two arms (SMC) and a bridge (kleisin). Together, they form a ring-like structure. “You can understand how important these protein complexes are when you look at their evolution,” explains Larissa Wilhelm, PhD student at the MPI of Biochemistry. “Structure and operating mode are quite similar in bacteria and humans.”

There are different possibilities as to how the SMC protein complex could pack up DNA. It could for example stick together the different DNA fibers. However, the Max Planck scientists were able to show in bacteria that the SMC protein arms embrace the DNA like a clip, thus enabling the connection of pieces of the DNA that lie wide apart from each other.

In a next step, the members of the research group “Chromosome Organization and Dynamics” want to find out whether the clip either opens for a short period of time in which it embraces already formed DNA loops, or whether the clip first binds to the DNA and then forms DNA loops itself by encasing the DNA.

“Our results could also help to better understand the complex organization of human chromosomes and hereby allow insights into the development of genetic defects such as Trisomy 21” says Stephan Gruber, group leader at the MPI of Biochemistry.

Original Publication
L. Wilhelm, F. Bürmann, A. Minnen, H.-C. Shin, C.P. Toseland, B.-H. Oh, S. Gruber: SMC condensin entraps chromosomal DNA by an ATP hydrolysis dependent loading mechanism in Bacillus subtilis. eLIFE, May 7, 2015.
DOI: 10.7554/eLife.06659

Contact
Dr. Stephan Gruber
Chromosome Organization and Dynamics
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 Martinsried
Germany
E-Mail: sgruber@biochem.mpg.de
www.biochem.mpg.de/gruber

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
www.biochem.mpg.de/news

Weitere Informationen:

http://www.biochem.mpg.de/en/news - More press release of the Max Planck Institute of Biochemistry
http://www.biochem.mpg.de/gruber - Website of the research group "Chromosome Organization and Dynamics" (Stephan Gruber)

Anja Konschak | Max-Planck-Institut für Biochemie

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>