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Initiation protein induced helix destabilization at the lambda origin: a prepriming step in DNA replication.

M Schnos·K Zahn·R B Inman·F R Blattner
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Abstract

The interaction of the lambda phage initiator protein, O, with the lambda origin sequence, ori, has been investigated. Binding of O, or its amino-terminal fragment, causes a major structural change within a 60 bp AT-rich region just to the right of the O-binding site. ATP or other molecular energy sources are not required. The modification, as assayed by nuclease sensitivity, is reduced when certain ori mutant sequences, which bind O but fail to replicate, are substituted for the wild-type sequence. The modification of DNA structure caused by the interaction of O is absolutely dependent on the presence of superhelical tension at the lambda origin sequence, and has several properties consistent with a strand separation reaction. We propose that this modification is a fundamental prepriming event that is the first stage in initiation of bidirectional replication in lambda after O binding.

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Bacteriophage lambdaBase SequenceBinding SitesDNA ReplicationDNA Restriction EnzymesDNA, Single-StrandedDNA, SuperhelicalDNA, ViralDNA-Binding ProteinsDeoxyribonuclease EcoRIEndonucleasesMolecular Sequence DataNucleic Acid DenaturationNucleotidasesRepetitive Sequences, Nucleic AcidSingle-Strand Specific DNA and RNA EndonucleasesViral ProteinsVirus ReplicationJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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M Schnos, K Zahn, R B Inman, F R Blattner. 1988-02-12. Initiation protein induced helix destabilization at the lambda origin: a prepriming step in DNA replication.. https://doi.org/10.1016/s0092-8674(88)80031-x

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