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Break-induced replication occurs by conservative DNA synthesis.

ABSTRACT: Break-induced replication (BIR) refers to recombination-dependent DNA synthesis initiated from one end of a DNA double-strand break and can extend for more than 100 kb. BIR initiates by Rad51-catalyzed strand invasion, but the mechanism for DNA synthesis is not known. Here, we used BrdU incorporation to track DNA synthesis during BIR and found that the newly synthesized strands segregate with the broken chromosome, indicative of a conservative mode of DNA synthesis. Furthermore, we show the frequency of BIR is reduced and product formation is progressively delayed when the donor is placed at an increasing distance from the telomere, consistent with replication by a migrating D-loop from the site of initiation to the telomere.

SUBMITTER: Donnianni RA

PROVIDER: S-EPMC3746906 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Break-induced replication occurs by conservative DNA synthesis.

Donnianni Roberto A RA Symington Lorraine S LS

Proceedings of the National Academy of Sciences of the United States of America 20130729 33

Break-induced replication (BIR) refers to recombination-dependent DNA synthesis initiated from one end of a DNA double-strand break and can extend for more than 100 kb. BIR initiates by Rad51-catalyzed strand invasion, but the mechanism for DNA synthesis is not known. Here, we used BrdU incorporation to track DNA synthesis during BIR and found that the newly synthesized strands segregate with the broken chromosome, indicative of a conservative mode of DNA synthesis. Furthermore, we show the freq ...[more]

PMID: 23898170

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