Molecular basis for Cdk1-regulated timing of Mis18 complex assembly and CENP-A deposition

EMBO Rep. 2017 Jun;18(6):894-905. doi: 10.15252/embr.201643564. Epub 2017 Apr 4.


The centromere, a chromosomal locus that acts as a microtubule attachment site, is epigenetically specified by the enrichment of CENP-A nucleosomes. Centromere maintenance during the cell cycle requires HJURP-mediated CENP-A deposition, a process regulated by the Mis18 complex (Mis18α/Mis18β/Mis18BP1). Spatial and temporal regulation of Mis18 complex assembly is crucial for its centromere association and function. Here, we provide the molecular basis for the assembly and regulation of the Mis18 complex. We show that the N-terminal region of Mis18BP1 spanning amino acid residues 20-130 directly interacts with Mis18α/β to form the Mis18 complex. Within Mis18α/β, the Mis18α MeDiY domain can directly interact with Mis18BP1. Mis18α/β forms a hetero-hexamer with 4 Mis18α and 2 Mis18β. However, only two copies of Mis18BP1 interact with Mis18α/β to form a hetero-octameric assembly, highlighting the role of Mis18 oligomerization in limiting the number of Mis18BP1 within the Mis18 complex. Furthermore, we demonstrate the involvement of consensus Cdk1 phosphorylation sites on Mis18 complex assembly and thus provide a rationale for cell cycle-regulated timing of Mis18 assembly and CENP-A deposition.

Keywords: CENP‐A deposition; Cdk1; HJURP; Mis18 complex; centromere.

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • CDC2 Protein Kinase / genetics
  • CDC2 Protein Kinase / metabolism*
  • CDC2 Protein Kinase / pharmacokinetics*
  • Cell Cycle / genetics
  • Centromere / genetics
  • Centromere / physiology
  • Centromere Protein A / metabolism*
  • Chromosomal Proteins, Non-Histone / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Gene Expression Regulation*
  • Humans
  • Nucleosomes
  • Phosphorylation
  • Protein Binding


  • Adaptor Proteins, Signal Transducing
  • Centromere Protein A
  • Chromosomal Proteins, Non-Histone
  • DNA-Binding Proteins
  • HJURP protein, human
  • MIS18A protein, human
  • Nucleosomes
  • CDC2 Protein Kinase
  • CDK1 protein, human