Cell growth, proliferation, differentiation and aging are tightly controlled by a complex network of signaling pathways. The RAS proteins and RAS signaling pathway play an essential role in normal cellular proliferation. Cancer occurs when proteins regulating these signaling pathways are over expressed or constitutively activated.
The Ras superfamily of small GTPases is composed of more than 150 members, which share a conserved structure and biochemical properties, acting as binary molecular switches turned on by binding GTP and off by hydrolyzing GTP to GDP. However, despite considerable structural and biochemical similarities, these proteins play multiple and divergent roles, being versatile and key regulators of virtually all fundamental cellular processes. Conversely, their dysfunction plays a crucial role in the pathogenesis of serious human diseases, including cancer and developmental syndromes.
