GINS is a DNA polymerase epsilon accessory factor during chromosomal DNA replication in budding yeast.
GINS is a protein complex found in eukaryotic cells that is composed of Sld5p, Psf1p, Psf2p, and Psf3p. GINS polypeptides are highly conserved in eukaryotes, and the GINS complex is required for chromosomal DNA replication in yeasts and Xenopus egg. This study reports purification and biochemical characterization of GINS from Saccharomyces cerevisiae. The results presented here demonstrate that GINS forms a 1:1 complex with DNA polymerase epsilon (Pol epsilon) holoenzyme and greatly stimulates its catalytic activity in vitro. In the presence of GINS, Pol epsilon is more processive and dissociates more readily from replicated DNA, while under identical conditions, proliferating cell nuclear antigen slightly stimulates Pol epsilon in vitro. These results strongly suggest that GINS is a Pol epsilon accessory protein during chromosomal DNA replication in budding yeast. Based on these results, we propose a model for molecular dynamics at eukaryotic chromosomal replication fork.
Seki
Takashi
T
Laboratories for Biomolecular Networks, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamada-oka, Suita, Osaka 565-0871; Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602.
Akita
Masaki
M
Laboratories for Biomolecular Networks, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamada-oka, Suita, Osaka 565-0871.
Kamimura
Yoichiro
Y
Division of Microbial Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.
Muramatsu
Sachiko
S
Division of Microbial Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.
Araki
Hiroyuki
H
Division of Microbial Genetics, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.
Sugino
Akio
A
Laboratories for Biomolecular Networks, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamada-oka, Suita, Osaka 565-0871; Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602. Electronic address: asugino@fbs.osaka-u.ac.jp.
D001483:Base Sequence; D002868:Chromosomal Proteins, Non-Histone / Q000502:physiology*; D004247:DNA / Q000737:chemistry; D004257:DNA Polymerase II / Q000737:chemistry*; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000502:physiology*; D020035:Holoenzymes / Q000737:chemistry; D008954:Models, Biological; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry; D011485:Protein Binding; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D017415:Ribonucleoprotein, U5 Small Nuclear; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology*
D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D020035:Holoenzymes; C077018:PRP8 protein, S cerevisiae; C513447:PSF2 protein, S cerevisiae; C513448:PSF3 protein, S cerevisiae; D010455:Peptides; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D017415:Ribonucleoprotein, U5 Small Nuclear; C474736:SLD5 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; D004257:DNA Polymerase II