title: Sld7, an Sld3-associated protein required for efficient chromosomal DNA replication in budding yeast.
abstract: Genetic screening of yeast for sld (synthetic lethality with dpb11) mutations has identified replication proteins, including Sld2, -3, and -5, and clarified the molecular mechanisms underlying eukaryotic chromosomal DNA replication. Here, we report a new replication protein, Sld7, identified by rescreening of sld mutations. Throughout the cell cycle, Sld7 forms a complex with Sld3, which associates with replication origins in a complex with Cdc45, binds to Dpb11 when phosphorylated by cyclin-dependent kinase, and dissociates from origins once DNA replication starts. However, Sld7 does not move with the replication fork. Sld7 binds to the nonessential N-terminal portion of Sld3 and reduces its affinity for Cdc45, a component of the replication fork. Although Sld7 is not essential for cell growth, its absence reduces the level of cellular Sld3, delays the dissociation from origins of GINS, a component of the replication fork, and slows S-phase progression. These results suggest that Sld7 is required for the proper function of Sld3 at the initiation of DNA replication.
authors.affiliation: Division of Microbial Genetics, National Institute of Genetics, Research Organization of Information and Systems, Shizuoka, Japan.
authors.forename: Tamon
authors.initials: T
authors.lastname: Tanaka
authors.forename: Toshiko
authors.initials: T
authors.lastname: Umemori
authors.forename: Shizuko
authors.initials: S
authors.lastname: Endo
authors.forename: Sachiko
authors.initials: S
authors.lastname: Muramatsu
authors.forename: Masato
authors.initials: M
authors.lastname: Kanemaki
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Kamimura
authors.forename: Chikashi
authors.initials: C
authors.lastname: Obuse
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Araki
mesh_terms: D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D015825:Chromosomes, Fungal / Q000378:metabolism*; D004252:DNA Mutational Analysis; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000378:metabolism*; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D011485:Protein Binding; D025941:Protein Interaction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C102209:CDC45 protein, S cerevisiae; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C097185:DPB11 protein, S cerevisiae; D050505:Mutant Proteins; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; C426020:Sld3 protein, S cerevisiae; C559742:Sld7 protein, S cerevisiae