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 2629-2641

Subject 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

More information

Latest update

4/28/2021