Cell cycle checkpoint regulators reach a zillion

Cell Cycle. 2013 May 15;12(10):1501-9. doi: 10.4161/cc.24637. Epub 2013 Apr 17.


Entry into mitosis is regulated by a checkpoint at the boundary between the G2 and M phases of the cell cycle (G2/M). In many organisms, this checkpoint surveys DNA damage and cell size and is controlled by both the activation of mitotic cyclin-dependent kinases (Cdks) and the inhibition of an opposing phosphatase, protein phosphatase 2A (PP2A). Misregulation of mitotic entry can often lead to oncogenesis or cell death. Recent research has focused on discovering the signaling pathways that feed into the core checkpoint control mechanisms dependent on Cdk and PP2A. Herein, we review the conserved mechanisms of the G2/M transition, including recently discovered upstream signaling pathways that link cell growth and DNA replication to cell cycle progression. Critical consideration of the human, frog and yeast models of mitotic entry frame unresolved and emerging questions in this field, providing a prediction of signaling molecules and pathways yet to be discovered.

Keywords: G2/M; G2/M checkpoint; Greatwall kinase; Zds proteins; cyclin-dependent kinase; mitotic entry; protein phosphatase 2A.

Publication types

  • Review

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Animals
  • Cell Cycle Checkpoints / physiology*
  • Cyclin-Dependent Kinases / metabolism*
  • Humans
  • Mitosis
  • Protein Phosphatase 2 / antagonists & inhibitors
  • Protein Phosphatase 2 / metabolism*
  • Saccharomyces cerevisiae / metabolism
  • Signal Transduction


  • Adaptor Proteins, Signal Transducing
  • Cyclin-Dependent Kinases
  • Protein Phosphatase 2