This new study reveals that under conditions of genotoxic stress, such as a break in DNA, the role of RNA paired with complementary DNA may be different, and beneficial, for a cell. "We discovered a mechanism in which transcript RNA anneals with complementary broken DNA and serves as a template for recombination and DNA repair, and thus has a role in both modifying and stabilizing the genome," Storici explained.
DNA damage can arise from a variety of causes both inside and outside the cell. Because the DNA consists of two complementary strands, one strand can normally be used to repair damage to the other. However, if the cell sustains breakage in both strands – known as a double-strand break – the repair options are more limited. Simply rejoining the broken ends carries a high risk of unwanted mutations or chromosome rearrangement, which can cause undesirable effects including cancer. Without successful repair, however, the cell may die or be unable to carry out important functions.
Beginning in 2007, Storici's research team showed that synthetic RNA introduced