DdrC protein repairs broken DNA fragments, restoring genomic coherence and making cells resistant to extreme conditions.
Researchers from Western University in Canada have identified a new protein that can prevent DNA damage, marking a significant discovery in the field of molecular biology. The findings, published in Nucleic Acids Research, highlights the critical role of the creatively named DNA Damage Repair Protein C, or DdrC for short, in facilitating the repair of damaged DNA [1].
Longevity.Technology: While much more research is needed, the discovery of DdrC opens up new possibilities for advancing understanding of DNA damage and repair mechanisms. Longevity watchers will be interested in this work, particularly those who subscribe to the DNA damage theory of aging, which describes aging as the accumulation of unresolved DNA damage over time, contributing to age-related diseases and genomic instability.
DdrC was found in a bacterium called Deinococcus radiodurans, known for its exceptional resilience to extreme conditions that would otherwise damage DNA. For example, it can withstand levels of radiation 5,000 to 10,000 times higher than those that would be lethal to human cells.
D. radiodurans also repairs DNA breaks that would normally be fatal for most organisms. Human cells, for instance, struggle to repair more than two breaks in their billion base pair genome, and failure to do so results in cell death. According to the researchers, DdrC enables the bacterium to repair hundreds of broken DNA fragments, restoring genomic coherence.
“It’s as if you had a player in the NFL who plays every game without a helmet or pads,” said lead researcher Robert Szabla. “He’d end up with a concussion and multiple broken bones every single game, but then miraculously make a full recovery overnight in time for practice the next day.” [2]
Using advanced imaging techniques, including the powerful X-ray capabilities at Canadian Light Source in Saskatoon, the researchers mapped DdrC’s 3D structure to uncover its function. The protein apparently works by scanning DNA for breaks, then swiftly trapping the damaged section like a mousetrap. This action not only prevents further damage but also acts as a beacon, signaling to the cell that repair is needed.
Unlike most proteins, which rely on complex networks to carry out functions, DdrC appears to operate independently, a rare feature in biological systems. Its effectiveness was demonstrated when the protein was introduced into E. coli, where it increased the bacterium’s resistance to UV radiation by over 40 times.
The researchers suggest that DdrC could potentially be used to enhance DNA repair mechanisms across a wide range of organisms, including humans.
“The ability to rearrange and edit and manipulate DNA in specific ways is the holy grail in biotechnology,” said Szabla. “What if you had a scanning system such as DdrC which patrolled your cells and neutralized damage when it happened? This might form the basis of a potential cancer vaccine.”
The Western University team intends to explore further, investigating other proteins within D. radiodurans that may offer additional tools for DNA repair.
[1] https://academic.oup.com/nar/advance-article/doi/10.1093/nar/gkae635/7717837
[2] https://www.lightsource.ca/public/news/2024-25-q2-jul-sept/newly-discovered-protein-stops-dna-damage.php
