title: Different sets of translesion synthesis DNA polymerases protect from genome instability induced by distinct food-derived genotoxins.
abstract: DNA lesions, induced by genotoxic compounds, block the processive replication fork but can be bypassed by specialized translesion synthesis (TLS) DNA polymerases (Pols). TLS safeguards the completion of replication, albeit at the expense of nucleotide substitution mutations. We studied the in vivo role of individual TLS Pols in cellular responses to benzo[a]pyrene diolepoxide (BPDE), a polycyclic aromatic hydrocarbon, and 4-hydroxynonenal (4-HNE), a product of lipid peroxidation. To this aim, we used mouse embryonic fibroblasts with targeted disruptions in the TLS-associated Pols η, ι, κ, and Rev1 as well as in Rev3, the catalytic subunit of TLS Polζ. After exposure, cellular survival, replication fork progression, DNA damage responses (DDR), and the induction of micronuclei were investigated. The results demonstrate that Rev1, Rev3, and, to a lesser extent, Polη are involved in TLS and the prevention of DDR and of DNA breaks, in response to both agents. Conversely, Polκ and the N-terminal BRCT domain of Rev1 are specifically involved in TLS of BPDE-induced DNA damage. We furthermore describe a novel role of Polι in TLS of 4-HNE-induced DNA damage in vivo. We hypothesize that different sets of TLS polymerases act on structurally different genotoxic DNA lesions in vivo, thereby suppressing genomic instability associated with cancer. Our experimental approach may provide a significant contribution in delineating the molecular bases of the genotoxicity in vivo of different classes of DNA-damaging agents.
authors.affiliation: Department of Toxicogenetics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors.forename: Piya
authors.initials: P
authors.lastname: Temviriyanukul
authors.forename: Matty
authors.initials: M
authors.lastname: Meijers
authors.forename: Sandrine
authors.initials: S
authors.lastname: van Hees-Stuivenberg
authors.forename: Jan J W A
authors.initials: JJ
authors.lastname: Boei
authors.forename: Frédéric
authors.initials: F
authors.lastname: Delbos
authors.forename: Haruo
authors.initials: H
authors.lastname: Ohmori
authors.forename: Niels
authors.initials: N
authors.lastname: de Wind
authors.forename: Jacob G
authors.initials: JG
authors.lastname: Jansen
mesh_terms: D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide / Q000633:toxicity*; D000447:Aldehydes / Q000633:toxicity*; D000818:Animals; D002461:Cell Line, Transformed; D049109:Cell Proliferation / Q000187:drug effects; D048749:Cytokinesis; D018736:DNA Adducts / Q000187:drug effects; D004249:DNA Damage; D004259:DNA-Directed DNA Polymerase / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000187:drug effects; D005506:Food Contamination; D051379:Mice; D018345:Mice, Knockout; D048629:Micronuclei, Chromosome-Defective / Q000139:chemically induced; D015162:Micronucleus Tests / Q000379:methods; D009153:Mutagens / Q000633:toxicity*
chemical_list: D000447:Aldehydes; D018736:DNA Adducts; D009153:Mutagens; D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide; D004259:DNA-Directed DNA Polymerase; C027576:4-hydroxy-2-nonenal