APC/C-mediated destruction of the centrosomal kinase Nek2A occurs in early mitosis and depends upon a cyclin A-type D-box

EMBO J. 2001 Dec 17;20(24):7117-27. doi: 10.1093/emboj/20.24.7117.


Nek2 is a NIMA-related kinase implicated in regulating centrosome structure at the G(2)/M transition. Two splice variants have been identified that exhibit distinct patterns of expression during cell cycle progression and development. Here we show that Nek2A, but not Nek2B, is destroyed upon entry into mitosis coincident with cyclin A destruction and in the presence of an active spindle assembly checkpoint. Destruction of Nek2A is mediated by the proteasome and is dependent upon the APC/C-Cdc20 ubiquitin ligase. Nek2 activity is not required for APC/C activation. Nek2A destruction in early mitosis is regulated by a motif in its extreme C-terminus which bears a striking resemblance to the extended destruction box (D-box) of cyclin A. Complete stabilization of Nek2A requires deletion of this motif and mutation of a KEN-box. Destruction of Nek2A is not inhibited by the cyclin B-type D-box, but the C-terminal domain of Nek2A inhibits destruction of both cyclins A and B. We propose that recognition of substrates by the APC/C-Cdc20 in early mitosis depends upon possession of an extended D-box motif.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Cyclin A / metabolism*
  • Cysteine Endopeptidases / metabolism
  • Humans
  • Ligases / metabolism*
  • Mitosis*
  • Molecular Sequence Data
  • Multienzyme Complexes / metabolism
  • NIMA-Related Kinases
  • Proteasome Endopeptidase Complex
  • Protein-Serine-Threonine Kinases / chemistry
  • Protein-Serine-Threonine Kinases / metabolism*
  • Sequence Homology, Amino Acid
  • Substrate Specificity
  • Tumor Cells, Cultured
  • Ubiquitin / metabolism


  • Cyclin A
  • Multienzyme Complexes
  • Ubiquitin
  • NEK2 protein, human
  • NIMA-Related Kinases
  • Protein-Serine-Threonine Kinases
  • Cysteine Endopeptidases
  • Proteasome Endopeptidase Complex
  • Ligases