Integration host factor stimulates the phage lambda pL promoter.

H Giladi; M Gottesman; A B Oppenheim

doi:10.1016/s0022-2836(05)80124-x

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Integration host factor stimulates the phage lambda pL promoter.

H Giladi·M Gottesman·A B Oppenheim

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Abstract

Escherichia coli integration host factor (IHF) is a small dimeric protein that binds to a specific DNA consensus sequence and produces DNA bending. Transcription from the bacteriophage lambda pL promoter is stimulated three- to fourfold by IHF both in vivo and in vitro. IHF binds with high-affinity to two tandem sites located just upstream from the pL promoter and enhances the formation of RNA polymerase-promoter closed complexes. The rate of isomerization to open complex is not influenced by IHF. IHF may stimulate recognition of pL by one or more of several mechanisms: (1) by bending DNA; (2) by making protein-protein contacts with RNA polymerase; or (3) by occluding a competing promoter upstream from pL.

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Bacterial Proteins Bacteriophage lambda Base Sequence DNA, Viral DNA-Binding Proteins DNA-Directed RNA Polymerases Escherichia coli Integration Host Factors Kinetics Molecular Sequence Data Nucleic Acid Conformation Promoter Regions, Genetic Restriction Mapping Transcription, Genetic Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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H Giladi, M Gottesman, A B Oppenheim. 1990-05-05. Integration host factor stimulates the phage lambda pL promoter.. https://doi.org/10.1016/s0022-2836(05)80124-x

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