The Rho GTPase effector ROCK regulates cyclin A, cyclin D1, and p27(Kip1) levels by distinct mechanisms

Croft, D. and Olson, M. (2006) The Rho GTPase effector ROCK regulates cyclin A, cyclin D1, and p27(Kip1) levels by distinct mechanisms. Molecular and Cellular Biology, 26(12), pp. 4612-4627. (doi:10.1128/MCB.02061-05)

Full text not currently available from Enlighten.

Abstract

The members of the Rho GTPase family are well known for their regulation of actin cytoskeletal structures. In addition, they influence progression through the cell cycle. The RhoA and RhoC proteins regulate numerous effector proteins, with a central and vital signaling role mediated by the ROCK I and ROCK 11 serine/threonine kinases. The requirement for ROCK function in the proliferation of numerous cell types has been revealed by studies utilizing ROCK-selective inhibitors such as Y-27632. However, the mechanisms by which ROCK signaling promotes cell cycle progression have not been thoroughly characterized. Using a conditionally activated ROCK-estrogen receptor fusion protein, we found that ROCK activation is sufficient to stimulate G(1)/S cell cycle progression in NIH 3T3 mouse fibroblasts. Further analysis revealed that ROCK acts via independent pathways to alter the levels of cell cycle regulatory proteins: cyclin D1 and p21(cip1) elevation via Ras and the mitogen-activated protein kinase pathway, increased cyclin A via LIM kinase 2, and reduction of p27(Kip1) protein levels. Therefore, the influence of ROCK on cell cycle regulatory proteins occurs by multiple independent mechanisms.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Olson, Professor Michael
Authors: Croft, D., and Olson, M.
College/School:College of Medical Veterinary and Life Sciences > Institute of Cancer Sciences
Journal Name:Molecular and Cellular Biology
ISSN:0270-7306

University Staff: Request a correction | Enlighten Editors: Update this record