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The DNA repair helicase UvrD is essential for replication fork reversal in replication mutants.

ABSTRACT: Replication forks arrested by inactivation of the main Escherichia coli DNA polymerase (polymerase III) are reversed by the annealing of newly synthesized leading- and lagging-strand ends. Reversed forks are reset by the action of RecBC on the DNA double-strand end, and in the absence of RecBC chromosomes are linearized by the Holliday junction resolvase RuvABC. We report here that the UvrD helicase is essential for RuvABC-dependent chromosome linearization in E. coli polymerase III mutants, whereas its partners in DNA repair (UvrA/B and MutL/S) are not. We conclude that UvrD participates in replication fork reversal in E. coli.

SUBMITTER: Flores MJ

PROVIDER: S-EPMC1299159 | biostudies-literature | 2004 Oct

REPOSITORIES: biostudies-literature

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The DNA repair helicase UvrD is essential for replication fork reversal in replication mutants.

Flores Maria Jose MJ Bidnenko Vladimir V Michel Bénédicte B

EMBO reports 20040917 10

Replication forks arrested by inactivation of the main Escherichia coli DNA polymerase (polymerase III) are reversed by the annealing of newly synthesized leading- and lagging-strand ends. Reversed forks are reset by the action of RecBC on the DNA double-strand end, and in the absence of RecBC chromosomes are linearized by the Holliday junction resolvase RuvABC. We report here that the UvrD helicase is essential for RuvABC-dependent chromosome linearization in E. coli polymerase III mutants, whe ...[more]

PMID: 15375374

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