Direct interaction between cohesin complex and DNA replication machinery.

Min-Jung Ryu; Beom-Jun Kim; Jeong-Won Lee; Min-Woo Lee; Hyun-Kyung Choi; Seong-Tae Kim

doi:10.1016/j.bbrc.2006.01.029

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Direct interaction between cohesin complex and DNA replication machinery.

Min-Jung Ryu·Beom-Jun Kim·Jeong-Won Lee·Min-Woo Lee·Hyun-Kyung Choi·Seong-Tae Kim

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Abstract

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.

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Cell Cycle Proteins Cell Line Chromosomal Proteins, Non-Histone DNA DNA Damage DNA Replication DNA-Binding Proteins Fungal Proteins Humans Minichromosome Maintenance Complex Component 6 Minichromosome Maintenance Complex Component 7 Nuclear Proteins Protein Binding Cohesins Structural Maintenance of Chromosome Protein 1 Journal Article Research Support, Non-U.S. Gov't

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Min-Jung Ryu, Beom-Jun Kim, Jeong-Won Lee, Min-Woo Lee, Hyun-Kyung Choi, Seong-Tae Kim. 2006-01-19. Direct interaction between cohesin complex and DNA replication machinery.. https://doi.org/10.1016/j.bbrc.2006.01.029

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