Direct interaction between cohesin complex and DNA replication machinery.
Structural maintenance of chromosome 1 (Smc1) is a multifunctional protein, which has been implicated in sister chromatid cohesion, DNA recombination and repair, and the activation of cell cycle checkpoints by ionizing radiation, ultraviolet light, and other genotoxic agents. In order to identify the proteins that interact with Smc1, we conducted the Tandem affinity purification (TAP) technique and analyzed the Smc1-interacting proteins via MALDI-TOF mass spectrometry. We identified minichromosome maintenance 7 (Mcm7), an essential component of the pre-replication complex, as a novel Smc1-interacting protein. Co-immunoprecipitation revealed an interaction occurring between Smc1 and Mcm7, both in vitro and in vivo. Using a GST pull-down assay, we determined that Smc1 interacts physically with Mcm7 via its N-terminal and hinge regions, and Mcm7 interacts with Smc1 via its middle region. Interestingly, we also discovered that Smc1 interacts with other DNA replication proteins, including Mcm6, RFC1, and DNA polymerase alpha. These results suggest that a functional link exists between the cohesin complex and DNA replication proteins.
Ryu
Min-Jung
MJ
Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, 300 Chonchon-Dong, Suwon, Kyunggi-Do 440-746, Republic of Korea.
Kim
Beom-Jun
BJ
Lee
Jeong-Won
JW
Lee
Min-Woo
MW
Choi
Hyun-Kyung
HK
Kim
Seong-Tae
ST
D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism*; D004249:DNA Damage; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000378:metabolism; D005656:Fungal Proteins / Q000378:metabolism*; D006801:Humans; D064151:Minichromosome Maintenance Complex Component 6; D064168:Minichromosome Maintenance Complex Component 7; D009687:Nuclear Proteins / Q000378:metabolism*; D011485:Protein Binding; D000097722:Cohesins; D000098550:Structural Maintenance of Chromosome Protein 1
D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004247:DNA; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D064151:Minichromosome Maintenance Complex Component 6; D064168:Minichromosome Maintenance Complex Component 7; D009687:Nuclear Proteins; D000097722:Cohesins; D000098550:Structural Maintenance of Chromosome Protein 1; C103258:MCM6 protein, human; C101624:MCM7 protein, human