title: Monomers and dimers of the RepA protein in plasmid pSC101 replication: domains in RepA.
abstract: The replication of plasmid pSC101 requires the plasmid-encoded protein RepA. This protein has a double role: it binds to three directly repeated sequences in the pSC101 origin and promotes replication of the plasmid; it binds to two inversely repeated sequences in its promoter region and regulates its own transcription. A series of RepA protein derivatives carrying deletions of the C-terminal region were assayed for specific binding. We found that the last third of the protein is not needed for binding to the various specific sites. Truncated proteins that still bind can also form heterodimers with a wild-type protein. Analysis of band retardation assays conducted with wild-type and truncated proteins indicates that RepA binds to directly repeated sequences as a monomer and to inversely repeated sequences as a dimer.
authors.affiliation: Department of Molecular Biology, University of Geneva, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Manen
authors.forename: L C
authors.initials: LC
authors.lastname: Upegui-Gonzalez
authors.forename: L
authors.initials: L
authors.lastname: Caro
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D004265:DNA Helicases; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010957:Plasmids; D011485:Protein Binding; D011506:Proteins; D017384:Sequence Deletion; D015534:Trans-Activators
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D046911:Macromolecular Substances; D011506:Proteins; D015534:Trans-Activators; C045264:replication initiator protein; D004265:DNA Helicases