Identification of a DNA nonhomologous end-joining complex in bacteria
journal contribution
posted on 2023-06-07, 13:33authored byGeoffrey R Weller, Boris Kysela, Rajat Roy, Louise M Tonkin, Elizabeth Scanlan, Marina Della, Susanne Krogh Devine, Jonathan P Day, Adam Wilkinson, Fabrizio d'Adda di Fagagna, Kevin M Devine, Richard P Bowater, Penny Jeggo, Stephen P Jackson, Aidan DohertyAidan Doherty
In eukaryotic cells, double-strand breaks (DSBs) in DNA are generally repaired by the pathway of homologous recombination or by DNA nonhomologous end joining (NHEJ). Both pathways have been highly conserved throughout eukaryotic evolution, but no equivalent NHEJ system has been identified in prokaryotes. The NHEJ pathway requires a DNA end-binding component called Ku. We have identified bacterial Ku homologs and show that these proteins retain the biochemical characteristics of the eukaryotic Ku heterodimer. Furthermore, we show that bacterial Ku specifically recruits DNA ligase to DNA ends and stimulates DNA ligation. Loss of these proteins leads to hypersensitivity to ionizing radiation in Bacillus subtilis. These data provide evidence that many bacteria possess a DNA DSB repair apparatus that shares many features with the NHEJ system of eukarya and suggest that this DNA repair pathway arose before the prokaryotic and eukaryotic lineages diverged.
History
Publication status
Published
Journal
Science
ISSN
1095-9203
Publisher
American Association for the Advancement of Science