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Ribonucleotides are signals for mismatch repair of leading-strand replication errors.

ABSTRACT: To maintain genome stability, mismatch repair of nuclear DNA replication errors must be directed to the nascent strand, likely by DNA ends and PCNA. Here we show that the efficiency of mismatch repair in Saccharomyces cerevisiae is reduced by inactivating RNase H2, which nicks DNA containing ribonucleotides incorporated during replication. In strains encoding mutator polymerases, this reduction is preferential for repair of mismatches made by leading-strand DNA polymerase ? as compared to lagging-strand DNA polymerase ?. The results suggest that RNase-H2-dependent processing of ribonucleotides transiently present in DNA after replication may direct mismatch repair to the continuously replicated nascent leading strand.

SUBMITTER: Lujan SA

PROVIDER: S-EPMC3658170 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Ribonucleotides are signals for mismatch repair of leading-strand replication errors.

Lujan Scott A SA Williams Jessica S JS Clausen Anders R AR Clark Alan B AB Kunkel Thomas A TA

Molecular cell 20130418 3

To maintain genome stability, mismatch repair of nuclear DNA replication errors must be directed to the nascent strand, likely by DNA ends and PCNA. Here we show that the efficiency of mismatch repair in Saccharomyces cerevisiae is reduced by inactivating RNase H2, which nicks DNA containing ribonucleotides incorporated during replication. In strains encoding mutator polymerases, this reduction is preferential for repair of mismatches made by leading-strand DNA polymerase ε as compared to laggin ...[more]

PMID: 23603118

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2020-05-14 | GSE141211 | GEO

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