Repair of double-strand breaks in bacteriophage T4 by a mechanism that involves extensive DNA replication.

Published

Journal Article

We investigated double-strand break (dsb) repair in bacteriophage T4 using a physical assay that involves a plasmid substrate with two inverted DNA segments. A dsb introduced into one repeat during a T4 infection induces efficient dsb repair using the second repeat as a template. This reaction is characterized by the following interesting features. First, the dsb induces a repair reaction that is directly coupled to extensive plasmid replication; the repaired/replicated product is in the form of long plasmid concatemers. Second, repair of the dsb site is frequently associated with exchange of flanking DNA. Third, the repair reaction is absolutely dependent on the products of genes uvsX, uvsY, 32, 46, and 59, which are also required for phage genomic recombination-dependent DNA replication. Fourth, the coupled repair/replication reaction is only partly dependent on endonuclease VII (gp49), suggesting that either another Holliday-junction-cleaving activity or an alternate resolution pathway is active during T4 infections. Because this repair reaction is directly coupled to extensive replication, it cannot be explained by the SZOSTAK et al. model. We present and discuss a model for the coupled repair/replication reaction, called the extensive chromosome replication model for dsb repair.

Full Text

Duke Authors

Cited Authors

  • George, JW; Kreuzer, KN

Published Date

  • August 1996

Published In

Volume / Issue

  • 143 / 4

Start / End Page

  • 1507 - 1520

PubMed ID

  • 8844141

Pubmed Central ID

  • 8844141

International Standard Serial Number (ISSN)

  • 0016-6731

Language

  • eng

Conference Location

  • United States