Abstract |
During replication in yeast, the three B family DNA replicases frequently incorporate ribonucleotides (rNMPs) into DNA, and their presence in the nuclear genome can affect genome stability. This prompted us to examine ribonucleotide incorporation by the fourth B family member, Pol ζ, the enzyme responsible for the majority of damage-induced mutagenesis in eukaryotes. We first show that Pol ζ inserts rNMPs into DNA and can extend primer termini containing 3'-ribonucleotides. We then measure rNMP incorporation by Pol ζ in the presence of its cofactors, RPA, RFC and PCNA and at normal cellular dNTP and rNTP concentrations that exist under unstressed conditions. Under these conditions, Pol ζ stably incorporates one rNMP for every 200-300 dNMPs incorporated, a frequency that is slightly higher than for the high fidelity replicative DNA polymerases. Under damage-induced conditions wherein cellular dNTP concentrations are elevated 5-fold, Pol ζ only incorporates one rNMP per 1300 dNMPs. Functional interaction of Pol ζ with the mutasome assembly factor Rev1 gives comparable rNMP incorporation frequencies. These results suggest that ribonucleotide incorporation into DNA during Pol ζ-mediated mutagenesis in vivo may be rare.
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Authors | Alena V Makarova, Stephanie A Nick McElhinny, Brian E Watts, Thomas A Kunkel, Peter M Burgers |
Journal | DNA repair
(DNA Repair (Amst))
Vol. 18
Pg. 63-7
(Jun 2014)
ISSN: 1568-7856 [Electronic] Netherlands |
PMID | 24674899
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, N.I.H., Intramural)
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Copyright | Copyright © 2014 Elsevier B.V. All rights reserved. |
Chemical References |
- DNA, Fungal
- Deoxyribonucleotides
- REV7 protein, S cerevisiae
- RFA1 protein, S cerevisiae
- Replication Protein A
- Ribonucleotides
- Saccharomyces cerevisiae Proteins
- DNA polymerase zeta
- Nucleotidyltransferases
- REV1 protein, S cerevisiae
- DNA-Directed DNA Polymerase
- REV3 protein, S cerevisiae
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Topics |
- DNA Damage
- DNA Replication
- DNA, Fungal
(metabolism)
- DNA-Directed DNA Polymerase
(metabolism)
- Deoxyribonucleotides
(metabolism)
- Mutation
- Nucleotidyltransferases
(genetics, metabolism)
- Replication Protein A
(metabolism)
- Ribonucleotides
(metabolism)
- Saccharomyces cerevisiae
(enzymology)
- Saccharomyces cerevisiae Proteins
(genetics, metabolism)
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