Cyclin A in cell cycle control and cancer

Cell Mol Life Sci. 2002 Aug;59(8):1317-26. doi: 10.1007/s00018-002-8510-y.


Cyclin A is particularly interesting among the cyclin family because it can activate two different cyclin-dependent kinases (CDKs) and functions in both S phase and mitosis. An embryonic form of cyclin A that is only essential for spermatogenesis is also present in some organisms. In S phase, phosphorylation of components of the DNA replication machinery such as CDC6 by cyclin A-CDK is believed to be important for initiation of DNA replication and to restrict the initiation to only once per cell cycle. In mitosis, the precise role of cyclin A is still obscure, but it may contribute to the control of cyclin B stability. Cyclin A starts to accumulate during S phase and is abruptly destroyed before metaphase. The synthesis of cyclin A is mainly controlled at the transcription level, involving E2F and other transcription factors. Removal of cyclin A is carried out by ubiquitin-mediated proteolysis, but whether the same anaphase-promoting complex/cyclosome targeting subunits are used as for cyclin B is debatable. Consistent with its role as a key cell cycle regulator, expression of cyclin A is found to be elevated in a variety of tumors.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Cell Cycle / physiology*
  • Cyclin A / biosynthesis
  • Cyclin A / metabolism*
  • Humans
  • Neoplasms / etiology*
  • Neoplasms / metabolism


  • Cyclin A