title: Role of PCNA and TLS polymerases in D-loop extension during homologous recombination in humans.
abstract: Homologous recombination (HR) is essential for maintaining genomic integrity, which is challenged by a wide variety of potentially lethal DNA lesions. Regardless of the damage type, recombination is known to proceed by RAD51-mediated D-loop formation, followed by DNA repair synthesis. Nevertheless, the participating polymerases and extension mechanism are not well characterized. Here, we present a reconstitution of this step using purified human proteins. In addition to Pol δ, TLS polymerases, including Pol η and Pol κ, also can extend D-loops. In vivo characterization reveals that Pol η and Pol κ are involved in redundant pathways for HR. In addition, the presence of PCNA on the D-loop regulates the length of the extension tracks by recruiting various polymerases and might present a regulatory point for the various recombination outcomes.
authors.affiliation: National Centre for Biomolecular Research, Masaryk University, Brno, Czech Republic.
authors.forename: Marek
authors.initials: M
authors.lastname: Sebesta
authors.forename: Peter
authors.initials: P
authors.lastname: Burkovics
authors.forename: Szilvia
authors.initials: S
authors.lastname: Juhasz
authors.forename: Sufang
authors.initials: S
authors.lastname: Zhang
authors.forename: Judit E
authors.initials: JE
authors.lastname: Szabo
authors.forename: Marietta Y W T
authors.initials: MY
authors.lastname: Lee
authors.forename: Lajos
authors.initials: L
authors.lastname: Haracska
authors.forename: Lumir
authors.initials: L
authors.lastname: Krejci
mesh_terms: D004249:DNA Damage; D004258:DNA Polymerase III / Q000737:chemistry / Q000502:physiology; D004261:DNA Replication; D004277:DNA, Single-Stranded / Q000096:biosynthesis; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry* / Q000502:physiology; D006367:HeLa Cells; D059765:Homologous Recombination; D006801:Humans; D009994:Osmolar Concentration; D018809:Proliferating Cell Nuclear Antigen / Q000737:chemistry* / Q000502:physiology; D034702:RNA-Binding Protein FUS / Q000737:chemistry / Q000502:physiology; D051135:Rad51 Recombinase / Q000737:chemistry; D000094769:DNA Polymerase iota; D000099270:Y-Family DNA Polymerases
chemical_list: D004258:DNA Polymerase III; D004277:DNA, Single-Stranded; D004259:DNA-Directed DNA Polymerase; D018809:Proliferating Cell Nuclear Antigen; D034702:RNA-Binding Protein FUS; D051135:Rad51 Recombinase; D000094769:DNA Polymerase iota; C495153:RAD51 protein, human; C404302:POLK protein, human; D000099270:Y-Family DNA Polymerases; C112338:Rad30 protein; C000722070:POLI protein, human
keywords: D-loop; DNA repair synthesis; Homologous recombination; Reconstitution; TLS polymerases