title: Cellular protein interactions with herpes simplex virus type 1 oriS.
abstract: The herpes simplex virus type 1 (HSV-1) origin of DNA replication, oriS, contains an AT-rich region and three highly homologous sequences, sites I, II, and III, identified as binding sites for the HSV-1 origin-binding protein (OBP). In the present study, interactions between specific oriS DNA sequences and proteins in uninfected cell extracts were characterized. The formation of one predominant protein-DNA complex, M, was demonstrated in gel shift assays following incubation of uninfected cell extracts with site I DNA. The cellular protein(s) that comprises complex M has been designated origin factor I (OF-I). The OF-I binding site was shown to partially overlap the OBP binding site within site I. Complexes with mobilities indistinguishable from that of complex M also formed with site II and III DNAs in gel shift assays. oriS-containing plasmid DNA mutated in the OF-I binding site exhibited reduced replication efficiency in transient assays, demonstrating a role for this site in oriS function. The OF-I binding site is highly homologous to binding sites for the cellular CCAAT DNA-binding proteins. The binding site for the CCAAT protein CP2 was found to compete for OF-I binding to site I DNA. These studies support a model involving the participation of cellular proteins in the initiation of HSV-1 DNA synthesis at oriS.
authors.affiliation: Division of Molecular Genetics, Dana-Farber Cancer Institute, Boston, Massachusetts.
authors.forename: C E
authors.initials: CE
authors.lastname: Dabrowski
authors.forename: P J
authors.initials: PJ
authors.lastname: Carmillo
authors.forename: P A
authors.initials: PA
authors.lastname: Schaffer
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D001667:Binding, Competitive; D016384:Consensus Sequence; D004247:DNA / Q000378:metabolism*; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000378:metabolism*; D018259:Herpesvirus 1, Human / Q000235:genetics* / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D015345:Oligonucleotide Probes; D012689:Sequence Homology, Nucleic Acid; D014709:Vero Cells; D014764:Viral Proteins / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D015345:Oligonucleotide Probes; D014764:Viral Proteins; C055789:origin-binding proteins, viral; D004247:DNA