Natural transformation specific DprA coordinate DNA double strand break repair pathways in heavily irradiated D. radiodurans

Deinococcus radiodurans exhibits remarkable survival under extreme conditions, including ionizing radiation, desiccation, and various DNA-damaging agents. It employs unique repair mechanisms, such as single-strand annealing (SSA) and extended synthesis-dependent strand annealing (ESDSA), to efficiently restore damaged DNA fragments. In this study, we investigate the regulatory role of the NT-specific protein DprA in DNA repair pathways following acute gamma radiation exposure. Our findings demonstrate that the absence of DprA leads to rapid repair of gamma radiation-induced DNA double-strand breaks (DSBs), with diminished involvement of the ESDSA pathway. Furthermore, our data suggest that the SSA pathway becomes the primary mechanism for DNA DSB repair in the absence of DprA. Overall, our results highlight the regulatory function of DprA in modulating the choice between SSA and ESDSA pathways for DNA repair in the radiation-resistant bacterium D. radioduransx.