The human GINS complex binds to and specifically stimulates human DNA polymerase alpha-primase.
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.
De Falco
Mariarosaria
M
Istituto di Biochimica delle Proteine, Consiglio Nazionale delle Ricerche, Via P. Castellino, 111, Napoli 80131, Italy.
Ferrari
Elena
E
De Felice
Mariarita
M
Rossi
Mosè
M
Hübscher
Ulrich
U
Pisani
Francesca M
FM
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D004247:DNA / Q000737:chemistry; D004256:DNA Polymerase I / Q000378:metabolism*; D019915:DNA Primase / Q000378:metabolism*; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism*; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism*; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification; D020349:Surface Plasmon Resonance
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters; D010446:Peptide Fragments; D011498:Protein Precursors; D021122:Protein Subunits; D011994:Recombinant Proteins; C073119:TAP1 protein, human; C405036:thyrotropin-releasing hormone-associated peptide 3, human; C071692:TAP2 protein, human; D004247:DNA; D019915:DNA Primase; C116932:DNA polymerase alpha-primase; D004256:DNA Polymerase I