title: Characterization and structure determination of the Cdt1 binding domain of human minichromosome maintenance (Mcm) 6.
abstract: The minichromosome maintenance (Mcm) 2-7 complex is the replicative helicase in eukaryotic species, and it plays essential roles in the initiation and elongation phases of DNA replication. During late M and early G(1), the Mcm2-7 complex is loaded onto chromatin to form prereplicative complex in a Cdt1-dependent manner. However, the detailed molecular mechanism of this loading process is still elusive. In this study, we demonstrate that the previously uncharacterized C-terminal domain of human Mcm6 is the Cdt1 binding domain (CBD) and present its high resolution NMR structure. The structure of CBD exhibits a typical "winged helix" fold that is generally involved in protein-nucleic acid interaction. Nevertheless, the CBD failed to interact with DNA in our studies, indicating that it is specific for protein-protein interaction. The CBD-Cdt1 interaction involves the helix-turn-helix motif of CBD. The results reported here provide insight into the molecular mechanism of Mcm2-7 chromatin loading and prereplicative complex assembly.
authors.affiliation: Department of Physics and Shanghai Key Laboratory for Magnetic Resonance, East China Normal University, Shanghai 200062, China.
authors.forename: Zhun
authors.initials: Z
authors.lastname: Wei
authors.forename: Changdong
authors.initials: C
authors.lastname: Liu
authors.forename: Xing
authors.initials: X
authors.lastname: Wu
authors.forename: Naining
authors.initials: N
authors.lastname: Xu
authors.forename: Bo
authors.initials: B
authors.lastname: Zhou
authors.forename: Chun
authors.initials: C
authors.lastname: Liang
authors.forename: Guang
authors.initials: G
authors.lastname: Zhu
mesh_terms: D018797:Cell Cycle Proteins / Q000737:chemistry* / Q000378:metabolism; D002455:Cell Division / Q000502:physiology; D002843:Chromatin / Q000737:chemistry / Q000378:metabolism; D004265:DNA Helicases / Q000737:chemistry* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D016193:G1 Phase / Q000502:physiology; D019077:Helix-Turn-Helix Motifs; D006801:Humans; D064151:Minichromosome Maintenance Complex Component 6; D064168:Minichromosome Maintenance Complex Component 7; D046912:Multiprotein Complexes / Q000737:chemistry / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D017434:Protein Structure, Tertiary
chemical_list: C467199:CDT1 protein, human; D018797:Cell Cycle Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; D004265:DNA Helicases; C103258:MCM6 protein, human; C101624:MCM7 protein, human; D064151:Minichromosome Maintenance Complex Component 6; D064168:Minichromosome Maintenance Complex Component 7