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Arrest of Viral Proliferation by Ectopic Copies of Its Cognate Replication Origin.

ABSTRACT: The initiation step of DNA replication is the crucial determinant of proliferation in all organisms. This step depends on the specific interaction of DNA sequences present at origins of DNA replication and their cognate activators. We wished to explore the hypothesis that the presence of ectopic origin copies may interfere with proper genome duplication. Bacteriophage ? was used as a model system. To this end, the outcome of an infection of an E. coli strain harboring ectopic copies of the ? origin region was analyzed. By measuring the effect on the host growth, viral production, and electro-microscopic visualization of the resulting ? replicative intermediates, we concluded that the ectopic copies had prevented the normal initiation step of ? DNA replication. These results suggest that DNA decoys encoding viral origins could constitute effective tools to specifically arrest viral proliferation.

SUBMITTER: Valenzuela MS

PROVIDER: S-EPMC4488673 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Arrest of Viral Proliferation by Ectopic Copies of Its Cognate Replication Origin.

Valenzuela Manuel S MS Sharan Chakradhari C

Genes 20150623 2

The initiation step of DNA replication is the crucial determinant of proliferation in all organisms. This step depends on the specific interaction of DNA sequences present at origins of DNA replication and their cognate activators. We wished to explore the hypothesis that the presence of ectopic origin copies may interfere with proper genome duplication. Bacteriophage λ was used as a model system. To this end, the outcome of an infection of an E. coli strain harboring ectopic copies of the λ ori ...[more]

PMID: 26110319

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Arrest of Viral Proliferation by Ectopic Copies of Its Cognate Replication Origin.

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Arrest of Viral Proliferation by Ectopic Copies of Its Cognate Replication Origin.

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