VISUALIZING THE DNA DOUBLE-STRAND BREAK PROCESS FOR THE FIRST TIME

Researchers from the Spanish National Cancer Research Centre (CNIO) have been able to observe for the first time DNA double chain breaks. X-ray crystallographic studies were performed at the ALBA Synchrotron and the Swiss Light Source. Results have been published in Nature Structural & Molecular Biology.

DNA breaks occur in several natural processes that are vital for life: mutagenesis, synthesis, recombination and repair. In the molecular biology field, they can also be generated synthetically.

Led by Guillermo Montoya from CNIO, a group of scientists have described in detail the mechanism of the DNA double-strand break process for the first time. To this end, they developed a method for producing biological crystals to illustrate the chemical process behind this reaction. They also created a computer simulation that makes this process – which lasts a matter of microseconds – visible to the human eye.

Data was collected from about 200 frozen crystals at macromolecular crystallography XALOC (ALBA) and PXI (Swiss Light Source, SLS, Switzerland) beamlines.

This information can be used in many biotechnological applications: from the correction of mutations to treat rare and genetic diseases, to the development of genetically modified organisms.

The study was carried out in collaboration with Modesto Orozco's computational group at IRB Barcelona, and has been funded by the Ministry of Economy & Competitiveness and the Ramón Areces Foundation.

Reference: "Visualizing phosphodiester-bond hydrolysis by an endonuclease" Rafael Molina, Stefano Stella, Pilar Redondo, Hansel Gomez, María José Marcaida, Modesto Orozco, Jesús Prieto & Guillermo Montoya
Nature Structural & Molecular Biology 22, 65-72 (2015), doi: 10.1038/nsmb.2932

Link to CNIO press release