title: Cell-Cycle-Regulated Interaction between Mcm10 and Double Hexameric Mcm2-7 Is Required for Helicase Splitting and Activation during S Phase.
abstract: Mcm2-7 helicase is loaded onto double-stranded origin DNA as an inactive double hexamer (DH) in G1 phase. The mechanisms of Mcm2-7 remodeling that trigger helicase activation in S phase remain unknown. Here, we develop an approach to detect and purify the endogenous DHs directly. Through cellular fractionation, we provide in vivo evidence that DHs are assembled on chromatin in G1 phase and separated during S phase. Interestingly, Mcm10, a robust MCM interactor, co-purifies exclusively with the DHs in the context of chromatin. Deletion of the main interaction domain, Mcm10 C terminus, causes growth and S phase defects, which can be suppressed through Mcm10-MCM fusions. By monitoring the dynamics of MCM DHs, we show a significant delay in DH dissolution during S phase in the Mcm10-MCM interaction-deficient mutants. Therefore, we propose an essential role for Mcm10 in Mcm2-7 remodeling through formation of a cell-cycle-regulated supercomplex with DHs.
authors.affiliation: State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, 2 Yuan-Ming-Yuan West Road, Beijing 100193, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Quan
authors.affiliation: State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, 2 Yuan-Ming-Yuan West Road, Beijing 100193, China.
authors.forename: Yisui
authors.initials: Y
authors.lastname: Xia
authors.affiliation: State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, 2 Yuan-Ming-Yuan West Road, Beijing 100193, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, 2 Yuan-Ming-Yuan West Road, Beijing 100193, China.
authors.forename: Jiamin
authors.initials: J
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, 2 Yuan-Ming-Yuan West Road, Beijing 100193, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, 2 Yuan-Ming-Yuan West Road, Beijing 100193, China.
authors.forename: Qinhong
authors.initials: Q
authors.lastname: Cao
authors.affiliation: Molecular and Computational Biology, USC Norris Cancer Center, and Chemistry Department, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Xiaojiang S
authors.initials: XS
authors.lastname: Chen
authors.affiliation: Braun Laboratories, California Institute of Technology, Pasadena, CA 91125, USA.
authors.forename: Judith L
authors.initials: JL
authors.lastname: Campbell
authors.affiliation: State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, 2 Yuan-Ming-Yuan West Road, Beijing 100193, China. Electronic address: lou@cau.edu.cn.
authors.forename: Huiqiang
authors.initials: H
authors.lastname: Lou
mesh_terms: D059447:Cell Cycle Checkpoints; D002843:Chromatin / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000378:metabolism; D016193:G1 Phase; D064110:Minichromosome Maintenance Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D016196:S Phase; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D002843:Chromatin; D004277:DNA, Single-Stranded; C076365:MCM10 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D064110:Minichromosome Maintenance Proteins
keywords: DNA replication; Mcm10; Mcm2-7; cell cycle; helicase activation