Signals from Ras and Rho GTPases interact to regulate expression of p21 Waf1/Cip1

摘要: Small GTPases act as molecular switches in intracellular signal-transduction pathways1. In the case of Ras family GTPases, one their most important roles is regulators cell proliferation, and mitogenic response to a variety growth factors oncogenes can be blocked by inhibiting function2,3. But certain situations, activation signalling pathways arrests cycle rather than causing proliferation4,5,6. Extracellular signals may trigger different cellular responses activating Ras-dependent varying degrees7,8,9. Other could also influence consequences signalling. Here we show that when through Ras-related GTPase Rho inhibited, constitutively active induces cyclin-dependent-kinase inhibitor p21Waf1/Cip1 entry into DNA-synthesis phase blocked. When active, induction suppressed DNA synthesis. Cells lack do not require for synthesis activated Ras, indicating that, once has become activated, primary requirement suppression induction.