Cell proliferation is regulated by temporal changes in gene expression in response to specific chemical and physical cues. These signals are relayed by a variety of intracellular signalling pathways including those activated by small GTPases, such as Ras, Rho, Rac and Cdc42. In this issue, Assoian and colleagues show that Rho confines the expression of cyclin D1 to mid-G1 phase of the cell cycle, by interactions with the ERK and Rac/Cdc42 signalling pathways.
- Mathew L. Coleman
- Christopher J. Marshall
