When DNA becomes severely damaged, it gets transported to a specific area in the cell—the nuclear pore complex—where it’s repaired. However, science hasn’t really figured out how the DNA gets there in the first place.
To try and solve this mystery, scientists from the University of Toronto used advanced microscopy techniques to track the course of damaged DNA in the cells. They learned that there’s a motor protein complex that acts as the “ambulance” for damaged DNA.
They also discovered that when the nuclear pore complex repairs the damaged DNA, it does so inaccurately. As a result, this “repaired” DNA still becomes stable and able to replicate, which can be very problematic.
Your DNA is what holds the instructions for all of your genetic material. In many cases, cancer occurs when chromosomes break and are not repaired properly. As a result, cells are no longer able to decode their instructions and continue multiplying, eventually causing a buildup of mutated DNA sequences, which can lead to cancer.
According to the authors of this study, these findings show that the location of the break within the nucleus of the cell is what will essentially determine the effectiveness of the repair.
Researchers will now begin working on trying to find more DNA “ambulances” and to figure out how exactly they contribute to the formation of cancerous cells. The hope is that these studies will eventually lead to the development of new anti-cancer treatments.
The findings were recently published in the journal Nature Communications.
Sources for Today’s Article:
Chung, D.K.C., et al., “Perinuclear tethers license telomeric DSBs for a broad kinesin- and NPC-dependent DNA repair process,” Nature Communications 2015; doi: 10.1038/ncomms8742.
“Scientists discover first ‘DNA ambulance’,” Science Daily web site, July 24, 2015; http://www.sciencedaily.com/releases/2015/07/150724081702.htm.
“Genes, DNA and cancer,” Cancer Research UK web site; http://www.cancerresearchuk.org/about-cancer/what-is-cancer/genes-dna-and-cancer, last accessed July 24, 2015.