Protein discovered as a precursor to cancer vaccine

Scientists have discovered a protein that can directly block DNA damage.

A damage response protein (DdrC) found in the bacterium Deinococcus radiodurans is opening up potential for cancer vaccines. The protein has the ability to detect DNA damage, block it, and alert the cell to initiate the repair process.

Most notably, DdrC functions quite independently, without the help of other proteins. In theory, this protein can attach to any organism, making it a promising candidate for a cancer vaccine.

In one experiment, the researchers inserted the DdrC gene into E. coli bacteria. They found that it repaired the DNA relatively easily and prevented further damage.

A DNA repair protein could open up potential for cancer vaccines (Photo: Science Alert).

"What surprised us was that it actually made E. coli 40 times more resistant to the damaging effects of UV radiation ," said biochemist Robert Szabla, author of the study.

'This seems to be a rare example where you have a protein and it really is like a standalone machine.'

In the human body, if there are more than two breaks in the 1 billion base pairs of the genome, the cell will not be able to repair itself and will die. But DdrC can help the cell repair hundreds of broken DNA segments into a unified genome.

The protein works like tying a shoelace. When it finds two single-strand breaks, DdrC binds to them and holds them together, squeezing the DNA. For pairs of double-strand breaks, the protein wraps the two ends of the DNA together to form a seamless loop.

These measures not only help prevent damage from getting worse, but also signal the cell's DNA repair mechanisms to come in and patch up the breaks.

Uncontrolled DNA damage is known to lead to a variety of diseases. For example, UV rays can damage the DNA in skin cells, increasing the risk of skin cancer. Preventing or reversing that damage could save lives.

'The ability to rearrange, edit, and manipulate DNA in specific ways is the ultimate goal in biotechnology ,' Szabla said. 'This could form the basis for a potential cancer vaccine.'