Multiple and specific initiation of T4 DNA replication.

C C Howe; P J Buckley; K M Carlson; A W Kozinski

doi:10.1128/jvi.12.1.130-148.1973

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Multiple and specific initiation of T4 DNA replication.

C C Howe·P J Buckley·K M Carlson·A W Kozinski

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Abstract

Partially replicated T4 DNA molecules (PRM) whose parental or progeny DNA was labeled with bromodeoxyuridine BUdR was analyzed by gradual shearing followed by CsCl banding of the sheared product. Analysis of PRM containing 18-mum replicated DNA showed that each replicated region was 3- to 6-mum long, indicating three to 6 replicative sites per molecule. Analysis of PRM containing 9-mum replicated DNA similarly indicated two to three replicated regions per molecule. DNA from the replicated regions of PRM containing 10-mum replicated DNA ("donor") was hybridized to DNA from mature phage ("recipient"), and the resulting hybrid was subjected to digestion with exonuclease I. The extent of protection of the recipient and more efficient self-annealing of progeny fragments from PRM indicated that the replicated regions represented 8 to 10 nonrandom locations of the genome. Possible significance of multiple sites for initiation of DNA replication is discussed.

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Bromodeoxyuridine Centrifugation, Density Gradient Coliphages DNA Replication DNA Viruses DNA, Viral Escherichia coli Exonucleases Hydrolysis Microscopy, Electron Models, Structural Nucleic Acid Hybridization Nucleotides Phosphorus Isotopes Thymidine Tritium Journal Article

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C C Howe, P J Buckley, K M Carlson, A W Kozinski. 1973. Multiple and specific initiation of T4 DNA replication.. https://doi.org/10.1128/jvi.12.1.130-148.1973

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