Sci. STKE, 2 November 2004
CELL DIVISION Cyclin into S Phase
Cyclin E functions as the activating subunit of the cyclin-dependent kinase 2 complex, which regulates the initiation of DNA synthesis (S phase) in proliferating cells. However, the phenotypes of cyclin E knockout mice are not identical to those of Cdk2 knockout mice, and so cyclin E may have other functions independent of its interaction with Cdk2. Matsumoto and Maller report the identification of one such function. Cyclin E was localized to the centrosome through a centrosomal localization signal (CLS), a 20-amino acid portion of the molecule. Expression of a CLS peptide that competes with the endogenous protein for binding to the centrosome, or expression of full-length cyclin E with a mutated CLS, inhibited the effect of cyclin E on DNA synthesis. Mutations that block interaction of cyclin E with Cdk2, however, did not hinder cyclin E's ability to promote DNA synthesis.
Citation: Cyclin into S Phase. Sci. STKE 2004, tw397 (2004).
Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882