The Human GINS Complex Binds to and Specifically Stimulates Human DNA Polymerase Alpha-Primase

EMBO Rep. 2007 Jan;8(1):99-103. doi: 10.1038/sj.embor.7400870. Epub 2006 Dec 15.

Abstract

The eukaryotic GINS complex has an essential role in the initiation and elongation phases of genome duplication. It is composed of four paralogous subunits--Sld5, Psf1, Psf2 and Psf3--which are ubiquitous and evolutionarily conserved in eukaryotic organisms. Here, we report the biochemical characterization of the human GINS complex (hGINS). The four hGINS subunits were coexpressed in Escherichia coli in a highly soluble form and purified as a complex. hGINS was shown to interact directly with the heterodimeric human DNA primase, by using either surface plasmon resonance measurements or by immunoprecipitation experiments carried out with anti-hGINS antibodies. The DNA polymerase alpha-primase synthetic activity was specifically stimulated by hGINS on various primed DNA templates. The significance of these findings is discussed in view of the molecular dynamics at the human replication fork.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 2
  • ATP Binding Cassette Transporter, Subfamily B, Member 3
  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • DNA / chemistry
  • DNA Polymerase I / metabolism*
  • DNA Primase / metabolism*
  • DNA Replication
  • Escherichia coli / genetics
  • Humans
  • Peptide Fragments / genetics
  • Peptide Fragments / metabolism*
  • Protein Precursors / genetics
  • Protein Precursors / metabolism*
  • Protein Subunits / genetics
  • Protein Subunits / metabolism
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / genetics
  • Recombinant Proteins / isolation & purification
  • Surface Plasmon Resonance

Substances

  • ATP Binding Cassette Transporter, Subfamily B, Member 2
  • ATP Binding Cassette Transporter, Subfamily B, Member 3
  • ATP-Binding Cassette Transporters
  • Peptide Fragments
  • Protein Precursors
  • Protein Subunits
  • Recombinant Proteins
  • TAP1 protein, human
  • thyrotropin-releasing hormone-associated peptide 3, human
  • TAP2 protein, human
  • DNA
  • DNA Polymerase I
  • DNA Primase
  • DNA polymerase alpha-primase