Polo-like kinase-1 is a target of the DNA damage checkpoint

Nat Cell Biol. 2000 Sep;2(9):672-6. doi: 10.1038/35023629.

Abstract

Polo-like kinases (PLKs) have an important role in several stages of mitosis. They contribute to the activation of cyclin B/Cdc2 and are involved in centrosome maturation and bipolar spindle formation at the onset of mitosis. PLKs also control mitotic exit by regulating the anaphase-promoting complex (APC) and have been implicated in the temporal and spatial coordination of cytokinesis. Experiments in budding yeast have shown that the PLK Cdc5 may be controlled by the DNA damage checkpoint. Here we report the effects of DNA damage on Polo-like kinase-1 (Plk1) in a variety of human cell lines. We show that Plk1 is inhibited by DNA damage in G2 and in mitosis. In line with this, we show that DNA damage blocks mitotic exit. DNA damage does not inhibit the kinase activity of Plk1 mutants in which the conserved threonine residue in the T-loop has been changed to aspartic acid, suggesting that DNA damage interferes with the activation of Plk1. Significantly, expression of these mutants can override the G2 arrest induced by DNA damage. On the basis of these data we propose that Plk1 is an important target of the DNA damage checkpoint, enabling cell-cycle arrests at multiple points in G2 and mitosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CDC2 Protein Kinase / metabolism
  • Cell Cycle Proteins / metabolism
  • Cyclin B / metabolism
  • Cyclin-Dependent Kinases / antagonists & inhibitors
  • DNA Damage*
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Kinetin
  • Mitosis
  • Polo-Like Kinase 1
  • Protein Kinases / genetics
  • Protein Kinases / metabolism*
  • Protein Serine-Threonine Kinases
  • Proto-Oncogene Proteins
  • Purines / pharmacology
  • Signal Transduction*
  • Tumor Cells, Cultured
  • cdc25 Phosphatases / metabolism

Substances

  • Cell Cycle Proteins
  • Cyclin B
  • Enzyme Inhibitors
  • Proto-Oncogene Proteins
  • Purines
  • olomoucine
  • Protein Kinases
  • Protein Serine-Threonine Kinases
  • CDC2 Protein Kinase
  • Cyclin-Dependent Kinases
  • CDC25C protein, human
  • cdc25 Phosphatases
  • Kinetin