title: Non-homologous end joining: Common interaction sites and exchange of multiple factors in the DNA repair process.
abstract: Non-homologous end-joining (NHEJ) is the dominant means of repairing chromosomal DNA double strand breaks (DSBs), and is essential in human cells. Fifteen or more proteins can be involved in the detection, signalling, synapsis, end-processing and ligation events required to repair a DSB, and must be assembled in the confined space around the DNA ends. We review here a number of interaction points between the core NHEJ components (Ku70, Ku80, DNA-PKcs, XRCC4 and Ligase IV) and accessory factors such as kinases, phosphatases, polymerases and structural proteins. Conserved protein-protein interaction sites such as Ku-binding motifs (KBMs), XLF-like motifs (XLMs), FHA and BRCT domains illustrate that different proteins compete for the same binding sites on the core machinery, and must be spatially and temporally regulated. We discuss how post-translational modifications such as phosphorylation, ADP-ribosylation and ubiquitinylation may regulate sequential steps in the NHEJ pathway or control repair at different types of DNA breaks.
authors.affiliation: Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, UK.
authors.forename: Stuart L
authors.initials: SL
authors.lastname: Rulten
authors.affiliation: Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, UK.
authors.forename: Gabrielle J
authors.initials: GJ
authors.lastname: Grundy
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D053903:DNA Breaks, Double-Stranded; D059766:DNA End-Joining Repair; D045643:DNA Repair Enzymes / Q000737:chemistry / Q000502:physiology; D006801:Humans; D054730:Protein Interaction Domains and Motifs; D060066:Protein Interaction Maps
chemical_list: D045643:DNA Repair Enzymes
keywords: DNA damage; DNA repair; non-homologous end-joining; protein-protein interactions