Sld3, which interacts with Cdc45 (Sld4), functions for chromosomal DNA replication in Saccharomyces cerevisiae
AUTOR(ES)
Kamimura, Yoichiro
FONTE
Oxford University Press
RESUMO
Cdc45, which binds to the minichromosomal maintenance (Mcm) proteins, has a pivotal role in the initiation and elongation steps of chromosomal DNA replication in eukaryotes. Here we show that throughout the cell cycle in Saccharomyces cerevisiae, Cdc45 forms a complex with a novel factor, Sld3. Consistently, Sld3 and Cdc45 associate simultaneously with replication origins in the chromatin immunoprecipitation assay: both proteins associate with early-firing origins in G1 phase and with late-firing origins in late S phase. Moreover, the origin associations of Sld3 and Cdc45 are mutually dependent. The temperature-sensitive sld3 mutation confers a defect in DNA replication at the restrictive temperature and reduces an interaction not only between Sld3 and Cdc45, but also between Cdc45 and Mcm2. These results suggest that the Sld3–Cdc45 complex associates with replication origins through Mcm proteins. At the restrictive temperature in sld3-5 cells, replication factor A, a single-strand DNA binding protein, does not associate with origins. Therefore, the origin association of Sld3–Cdc45 complex is prerequisite for origin unwinding in the initiation of DNA replication.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=125422Documentos Relacionados
- Sld2, Which Interacts with Dpb11 in Saccharomyces cerevisiae, Is Required for Chromosomal DNA Replication
- CDC45 is required in conjunction with CDC7/DBF4 to trigger the initiation of DNA replication
- A requirement for MCM7 and Cdc45 in chromosome unwinding during eukaryotic DNA replication
- SpSld3 Is Required for Loading and Maintenance of SpCdc45 on Chromatin in DNA Replication in Fission Yeast
- CDC45 and DPB11 are required for processive DNA replication and resistance to DNA topoisomerase I-mediated DNA damage