title: The human Tim-Tipin complex interacts directly with DNA polymerase epsilon and stimulates its synthetic activity.
abstract: The Tim-Tipin complex plays an important role in the S phase checkpoint and replication fork stability in metazoans, but the molecular mechanism underlying its biological function is poorly understood. Here, we present evidence that the recombinant human Tim-Tipin complex (and Tim alone) markedly enhances the synthetic activity of DNA polymerase ε. In contrast, no significant effect on the synthetic ability of human DNA polymerase α and δ by Tim-Tipin was observed. Surface plasmon resonance measurements and co-immunoprecipitation experiments revealed that recombinant DNA polymerase ε directly interacts with either Tim or Tipin. In addition, the results of DNA band shift assays suggest that the Tim-Tipin complex (or Tim alone) is able to associate with DNA polymerase ε bound to a 40-/80-mer DNA ligand. Our results are discussed in view of the molecular dynamics at the human DNA replication fork.
authors.affiliation: Istituto di Biochimica delle Proteine, Consiglio Nazionale delle Ricerche, Via P. Castellino 111, 80131 Naples, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Aria
authors.forename: Mariarita
authors.initials: M
authors.lastname: De Felice
authors.forename: Roberta
authors.initials: R
authors.lastname: Di Perna
authors.forename: Shuji
authors.initials: S
authors.lastname: Uno
authors.forename: Hisao
authors.initials: H
authors.lastname: Masai
authors.forename: Juhani E
authors.initials: JE
authors.lastname: Syväoja
authors.forename: Barbara
authors.initials: B
authors.lastname: van Loon
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hübscher
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Pisani
mesh_terms: D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins; D002460:Cell Line; D004247:DNA / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D004257:DNA Polymerase II / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins; D006801:Humans; D046912:Multiprotein Complexes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020349:Surface Plasmon Resonance / Q000379:methods
chemical_list: D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; C516227:Tipin protein, human; D004247:DNA; D004257:DNA Polymerase II
keywords: DNA Damage; DNA Enzymes; DNA Polymerase; DNA Repair; DNA Replication; DNA-Protein Interaction; Fork Protection Complex; Tim-Tipin Complex