title: Two-polymerase mechanisms dictate error-free and error-prone translesion DNA synthesis in mammals.
abstract: DNA replication across blocking lesions occurs by translesion DNA synthesis (TLS), involving a multitude of mutagenic DNA polymerases that operate to protect the mammalian genome. Using a quantitative TLS assay, we identified three main classes of TLS in human cells: two rapid and error-free, and the third slow and error-prone. A single gene, REV3L, encoding the catalytic subunit of DNA polymerase zeta (pol zeta), was found to have a pivotal role in TLS, being involved in TLS across all lesions examined, except for a TT cyclobutane dimer. Genetic epistasis siRNA analysis indicated that discrete two-polymerase combinations with pol zeta dictate error-prone or error-free TLS across the same lesion. These results highlight the central role of pol zeta in both error-prone and error-free TLS in mammalian cells, and show that bypass of a single lesion may involve at least three different DNA polymerases, operating in different two-polymerase combinations.
authors.affiliation: Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Sigal
authors.initials: S
authors.lastname: Shachar
authors.forename: Omer
authors.initials: O
authors.lastname: Ziv
authors.forename: Sharon
authors.initials: S
authors.lastname: Avkin
authors.forename: Sheera
authors.initials: S
authors.lastname: Adar
authors.forename: John
authors.initials: J
authors.lastname: Wittschieben
authors.forename: Thomas
authors.initials: T
authors.lastname: Reissner
authors.forename: Stephen
authors.initials: S
authors.lastname: Chaney
authors.forename: Errol C
authors.initials: EC
authors.lastname: Friedberg
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Wang
authors.forename: Thomas
authors.initials: T
authors.lastname: Carell
authors.forename: Nicholas
authors.initials: N
authors.lastname: Geacintov
authors.forename: Zvi
authors.initials: Z
authors.lastname: Livneh
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004249:DNA Damage; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry / Q000378:metabolism*; D019281:Dimerization; D004843:Epistasis, Genetic; D006801:Humans; D007700:Kinetics; D051379:Mice; D016296:Mutagenesis; D011740:Pyrimidine Dimers / Q000737:chemistry; D034741:RNA, Small Interfering / Q000378:metabolism; D051760:Xeroderma Pigmentosum Group A Protein / Q000378:metabolism
chemical_list: D011740:Pyrimidine Dimers; D034741:RNA, Small Interfering; C497314:XPA protein, human; D051760:Xeroderma Pigmentosum Group A Protein; D004247:DNA; D004259:DNA-Directed DNA Polymerase