Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

3d Structure of a DNA Damage Repair Complex

28.11.2007
The work was co directed by Dr. Aidan Doherty from the Sussex Centre for Genome Damage and Stability in the UK and by Dr. Luis Blanco from the Centro de Biología Molecular Severo Ochoa (CSIC-UAM).

This is the first study that shows the 3D structure of a molecular complex found in the bacteria Mycobacterium tuberculosis that repairs DNA damage. According to the biochemical data, this reflects a stage of the search for compatible microhomologies. This is the process of seeking non complementary extremes of DNA that would never link under normal conditions, known as non-homologous end joining (NHEJ). Among the Spanish participating researchers are Dr. Raquel Juárez Santos, and Dr. Angel J. Picher Serantes.

The double strand breaking of DNA is considered the most lethal kind of damage for our genome, since an error in its repair potentially represents cell death or tumour growth. Non-homologous end joining is a repair process for the double strand breaking of DNA which can operate at any stage of the cellular cycle, and it is essential in maintaining the genome stability in mammals. The process uses a combination of proteins responsible for the protection and maintenance of the proximity of the ends as well as all the actions necessary to repair the rupture. As an analogy, NHEJ operates like an adhesive kit that cleans the damaged area, fills the missing parts, and glues together the loose ends, even if is inevitable that some nucleotides are changed or lost in the process. A potential hazard of this mechanism is simultaneous ruptures, since it is possible that the strands are confused and the wrong strands are glued together, and such a translocation could activate an oncogene.

This study, published in Science magazine, identifies the structural bases of the NHEJ process in the DNA of the bacteria Mycobacterium tuberculosis, and shows for the first time the 3D structure of a NHEJ repairing complex. Up until now, there was little information about the different processing activities that occur in sequential coordination during the NHEJ, either about the independent proteins of mammals, or the different parts of the same protein like in bacteria. The union of the extremities shown in the 3D structure and described in this study, shows the stage of alignment of the ends, prior to the processing by the activity of nuclease (DNA cleaver), polymerase (DNA synthesis) and ligase (DNA binding), all carried out by the enzyme LigD (DNA repair) in the case of bacteria. This study can be extrapolated to the NHEJ of mammals.

... more about:
»NHEJ »Strand »repair

From a more applied point of view, this analysis identifies the polymerization of the bacterial LigD as a possible target to hamper the repair process of double strand breaks in these organisms. It has been proven that the NHEJ is a source of genetic variability in bacteria, necessary for their adaptation and survival in genotoxic (toxic for DNA) environments. The selective elimination of this process could have applications such as treatments that avoid the generation of antibiotic resistant bacteria.

Oficina de Cultura Científica | alfa
Further information:
http://dx.doi.org/10.1126/science.1145112

Further reports about: NHEJ Strand repair

More articles from Life Sciences:

nachricht Topologische Quantenchemie
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

nachricht Topological Quantum Chemistry
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

Ultrathin device harvests electricity from human motion

24.07.2017 | Power and Electrical Engineering

Scientists announce the quest for high-index materials

24.07.2017 | Materials Sciences

ADIR Project: Lasers Recover Valuable Materials

24.07.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>