title: PrimPol Is Required for Replicative Tolerance of G Quadruplexes in Vertebrate Cells.
abstract: G quadruplexes (G4s) can present potent blocks to DNA replication. Accurate and timely replication of G4s in vertebrates requires multiple specialized DNA helicases and polymerases to prevent genetic and epigenetic instability. Here we report that PrimPol, a recently described primase-polymerase (PrimPol), plays a crucial role in the bypass of leading strand G4 structures. While PrimPol is unable to directly replicate G4s, it can bind and reprime downstream of these structures. Disruption of either the catalytic activity or zinc-finger of PrimPol results in extreme G4-dependent epigenetic instability at the BU-1 locus in avian DT40 cells, indicative of extensive uncoupling of the replicative helicase and polymerase. Together, these observations implicate PrimPol in promoting restart of DNA synthesis downstream of, but closely coupled to, G4 replication impediments.
authors.affiliation: MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
authors.forename: Davide
authors.initials: D
authors.lastname: Schiavone
authors.affiliation: Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK.
authors.forename: Stanislaw K
authors.initials: SK
authors.lastname: Jozwiakowski
authors.affiliation: MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
authors.forename: Marina
authors.initials: M
authors.lastname: Romanello
authors.affiliation: MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Guilbaud
authors.affiliation: Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Guilliam
authors.affiliation: Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK.
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Bailey
authors.affiliation: MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK. Electronic address: jes@mrc-lmb.cam.ac.uk.
authors.forename: Julian E
authors.initials: JE
authors.lastname: Sale
authors.affiliation: Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK. Electronic address: ajd21@sussex.ac.uk.
authors.forename: Aidan J
authors.initials: AJ
authors.lastname: Doherty
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002460:Cell Line; D002645:Chickens; D042002:Chromatin Assembly and Disassembly; D004247:DNA / Q000096:biosynthesis* / Q000737:chemistry; D019915:DNA Primase / Q000235:genetics / Q000378:metabolism*; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000235:genetics / Q000378:metabolism*; D044127:Epigenesis, Genetic; D054856:G-Quadruplexes; D042822:Genomic Instability; D006657:Histones / Q000378:metabolism; D008969:Molecular Sequence Data; D064251:Multifunctional Enzymes / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
chemical_list: D030161:Avian Proteins; D006657:Histones; D064251:Multifunctional Enzymes; D004247:DNA; D019915:DNA Primase; C585901:PrimPol protein, human; D004259:DNA-Directed DNA Polymerase
keywords: G quadruplexes; PrimPol; TLS; epigenetic instability; polymerase; primase; replication stalling; repriming