Dynamics of Ku and bacterial non-homologous end-joining characterized using single DNA molecule analysis
Journal article, 2021
We use single-molecule techniques to characterize the dynamics of prokaryotic DNA repair by non-homologous end-joining (NHEJ), a system comprised only of the dimeric Ku and Ligase D (LigD). The Ku homodimer alone forms a ∼2 s synapsis between blunt DNA ends that is increased to ∼18 s upon addition of LigD, in a manner dependent on the C-terminal arms of Ku. The synapsis lifetime increases drastically for 4 nt complementary DNA overhangs, independently of the C-terminal arms of Ku. These observations are in contrast to human Ku, which is unable to bridge either of the two DNA substrates. We also demonstrate that bacterial Ku binds the DNA ends in a cooperative manner for synapsis initiation and remains stably bound at DNA junctions for several hours after ligation is completed, indicating that a system for removal of the proteins is active in vivo. Together these experiments shed light on the dynamics of bacterial NHEJ in DNA end recognition and processing. We speculate on the evolutionary similarities between bacterial and eukaryotic NHEJ and discuss how an increased understanding of bacterial NHEJ can open the door for future antibiotic therapies targeting this mechanism.
Author
Robin Öz
Chalmers, Biology and Biological Engineering, Chemical Biology
Jing L. Wang
Ecole Normale Superieure (ENS)
Institut Jacques Monod
Raphael Guerois
University Paris-Saclay
Gaurav Goyal
Chalmers, Biology and Biological Engineering, Chemical Biology
Sriram Kesarimangalam
Chalmers, Biology and Biological Engineering, Chemical Biology
Virginie Ropars
University Paris-Saclay
Rajhans Sharma
Chalmers, Biology and Biological Engineering, Chemical Biology
Firat Koca
Student at Chalmers
Jean Baptiste Charbonnier
University Paris-Saclay
M. Modesti
Equipe Labélisée
Centre de Recherche en Cancerologie de Marseille
Terence R. Strick
Equipe Labélisée
Institut Jacques Monod
Ecole Normale Superieure (ENS)
Fredrik Westerlund
Chalmers, Biology and Biological Engineering, Chemical Biology
Nucleic Acids Research
0305-1048 (ISSN) 1362-4962 (eISSN)
Vol. 49 5 2629-2641Subject Categories
Biophysics
Microbiology
Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
DOI
10.1093/nar/gkab083
PubMed
33590005