Cellular and Molecular Life Sciences CMLS

, Volume 59, Issue 8, pp 1317–1326

Cyclin A in cell cycle control and cancer

  • C. H. Yam
  • T. K. Fung
  • R. Y. C. Poon

DOI: 10.1007/s00018-002-8510-y

Cite this article as:
Yam, C., Fung, T. & Poon, R. CMLS, Cell. Mol. Life Sci. (2002) 59: 1317. doi:10.1007/s00018-002-8510-y

Abstract.

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.

Key words. Cell cycle control; cyclin; cyclin-dependent kinases; proteolysis; tumorigenesis.

Copyright information

© Birkhäuser Verlag, 2002

Authors and Affiliations

  • C. H. Yam
    • 2
  • T. K. Fung
    • 1
  • R. Y. C. Poon
    • 1
  1. 1.Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong), Fax + 852 2358 1552, e-mail: bcrandy@ust.hkHK
  2. 2.Present address: Division of Biology, MC 156-29, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (USA)US