1. The human Tim-Tipin complex interacts directly with DNA polymerase epsilon and stimulates its synthetic activity.
- Author
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Aria V, De Felice M, Di Perna R, Uno S, Masai H, Syväoja JE, van Loon B, Hübscher U, and Pisani FM
- Subjects
- Cell Cycle Proteins, Cell Line, DNA-Binding Proteins, Humans, Surface Plasmon Resonance methods, Carrier Proteins chemistry, Carrier Proteins genetics, Carrier Proteins metabolism, DNA biosynthesis, DNA chemistry, DNA genetics, DNA Polymerase II chemistry, DNA Polymerase II genetics, DNA Polymerase II metabolism, Multiprotein Complexes chemistry, Multiprotein Complexes genetics, Multiprotein Complexes metabolism, Nuclear Proteins chemistry, Nuclear Proteins genetics, Nuclear Proteins metabolism
- 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.
- Published
- 2013
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