A novel ring-like complex of Xenopus proteins essential for the initiation of DNA replication.
We have identified Xenopus homologs of the budding yeast Sld5 and its three interacting proteins. These form a novel complex essential for the initiation of DNA replication in Xenopus egg extracts. The complex binds to chromatin in a manner dependent on replication licensing and S-phase CDK. The chromatin binding of the complex and that of Cdc45 are mutually dependent and both bindings require Xenopus Cut5, the yeast homolog of which interacts with Sld5. On replicating chromatin the complex interacts with Cdc45 and MCM, putative components of replication machinery. Electron microscopy further reveals that the complex has a ring-like structure. These results suggest that the complex plays an essential role in the elongation stage of DNA replication as well as the initiation stage.
Department of Biology, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
Yumiko
Y
Kubota
Youhei
Y
Takase
Yasunori
Y
Komori
Yoshitami
Y
Hashimoto
Toshiaki
T
Arata
Yoichiro
Y
Kamimura
Hiroyuki
H
Araki
Haruhiko
H
Takisawa
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics; D004261:DNA Replication / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism*; D016415:Sequence Alignment; D011503:Transglutaminases / Q000378:metabolism*; D014981:Xenopus
C102209:CDC45 protein, S cerevisiae; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C082463:RAD4 protein, S pombe; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D011503:Transglutaminases