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Linking double-stranded DNA breaks to the recombination activating gene complex directs repair to the nonhomologous end-joining pathway.

ABSTRACT: Two major DNA repair pathways, nonhomologous end-joining (NHEJ) and homologous recombination (HR), repair double-stranded DNA breaks (DSBs) in all eukaryotes. Additionally, several alternative end-joining pathways (or subpathways) have been reported that characteristically use short-sequence homologies at the DNA ends to facilitate joining. How a cell chooses which DNA repair pathway to use (at any particular DSB) is a central and largely unanswered question. For one type of DSB, there is apparently no choice. DSBs mediated by the lymphocyte-specific recombination activating gene (RAG) endonuclease are repaired virtually exclusively by NHEJ. Here we demonstrate that non-RAG-mediated DSBs can be similarly forced into the NHEJ pathway by physical association with the RAG endonuclease.

SUBMITTER: Cui X

PROVIDER: S-EPMC2040436 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Linking double-stranded DNA breaks to the recombination activating gene complex directs repair to the nonhomologous end-joining pathway.

Cui Xiaoping X Meek Katheryn K

Proceedings of the National Academy of Sciences of the United States of America 20071015 43

Two major DNA repair pathways, nonhomologous end-joining (NHEJ) and homologous recombination (HR), repair double-stranded DNA breaks (DSBs) in all eukaryotes. Additionally, several alternative end-joining pathways (or subpathways) have been reported that characteristically use short-sequence homologies at the DNA ends to facilitate joining. How a cell chooses which DNA repair pathway to use (at any particular DSB) is a central and largely unanswered question. For one type of DSB, there is appare ...[more]

PMID: 17939999

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