Cdc2-independent induction of premature mitosis by okadaic acid in HeLa cells

Exp Cell Res. 1998 Jul 10;242(1):1-9. doi: 10.1006/excr.1998.4115.


The induction of premature mitosis by okadaic acid (OA) in HeLa cells in S-phase or in G2-phase has been studied using light microscopy, immunofluorescence, and immunochemical techniques. The observations indicate an involvement of a cdc2-independent pathway in these cells. It has been claimed that inhibition of an OA-sensitive phosphatase, possibly of PP1, induces activation of a kinase which is sensitive to staurosporine and Zn2+. This kinase brings about mitosis-specific cytoskeletal rearrangements, chromosome condensation, and nuclear envelope breakdown, inducing a mitosis-like state. However, other mitotic events do not follow. The possibility that this kinase may be a NIMA-like Nek2 kinase is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CDC2 Protein Kinase / physiology*
  • Cantharidin / pharmacology
  • Enzyme Inhibitors / pharmacology
  • G2 Phase
  • HeLa Cells
  • Humans
  • Mitosis / drug effects*
  • NIMA-Related Kinases
  • Okadaic Acid / pharmacology*
  • Phosphoprotein Phosphatases / antagonists & inhibitors
  • Phosphoprotein Phosphatases / physiology*
  • Protein-Serine-Threonine Kinases / antagonists & inhibitors
  • Protein-Serine-Threonine Kinases / physiology
  • S Phase


  • Enzyme Inhibitors
  • Okadaic Acid
  • NEK2 protein, human
  • NIMA-Related Kinases
  • Protein-Serine-Threonine Kinases
  • CDC2 Protein Kinase
  • Phosphoprotein Phosphatases
  • Cantharidin