title: Electron microscopic analysis reveals that replication factor C is sequestered by single-stranded DNA.
abstract: Replication factor C (RF-C) is a eukaryotic heteropentameric protein required for DNA replication and repair processes by loading proliferating cell nuclear antigen (PCNA) onto DNA in an ATP-dependent manner. Prior to loading PCNA, RF-C binds to DNA. This binding is thought to be restricted to a specific DNA structure, namely to a primer/template junction. Using the electron microscope we have examined the affinity of human heteropentameric RF-C and the DNA-binding region within the large subunit of RF-C from Drosophila melanogaster (dRF-Cp140) to heteroduplex DNA. The electron microscopic data indicate that both human heteropentameric RF-C and the DNA-binding region within dRF-Cp140 are sequestered by single-stranded DNA. No preferential affinity for the 3' or 5' transition points from single- to double-stranded DNA was evident.
authors.affiliation: Institute for Cell Biology, ETH-Hönggerberg, CH-8049 Zürich, Switzerland.
authors.forename: R C
authors.initials: RC
authors.lastname: Keller
authors.forename: R
authors.initials: R
authors.lastname: Mossi
authors.forename: G
authors.initials: G
authors.lastname: Maga
authors.forename: R E
authors.initials: RE
authors.lastname: Wellinger
authors.forename: U
authors.initials: U
authors.lastname: Hübscher
authors.forename: J M
authors.initials: JM
authors.lastname: Sogo
mesh_terms: D000818:Animals; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D004330:Drosophila / Q000737:chemistry; D006367:HeLa Cells; D018398:Homeodomain Proteins; D006801:Humans; D008854:Microscopy, Electron; D015778:Minor Histocompatibility Antigens; D009692:Nucleic Acid Heteroduplexes / Q000648:ultrastructure; D010957:Plasmids / Q000737:chemistry; D011485:Protein Binding; D019253:Proto-Oncogene Proteins c-bcl-2; D051818:Replication Protein C; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins
chemical_list: C096816:BCL2-related protein A1; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; C096063:MATA1 protein, S cerevisiae; D015778:Minor Histocompatibility Antigens; D009692:Nucleic Acid Heteroduplexes; D019253:Proto-Oncogene Proteins c-bcl-2; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D051818:Replication Protein C