Ras is a membrane protein, which is synthesized in the cytoplasm, but bound to the membrane to interact with the receptor-ligand-signal protein complex. It is the class of signal protein, which functions like G-proteins. The activated Ras then activates a serine-threonine kinase called Raf. It initiates a cascade of reactions and terminates with the activation of MAP (mitogen-activated protein) kinase.
Thus the activated Ras protein has autocatalytic property, which refers to the catalytic property leading to its own deactivation without any external influences. The Ras protein would remain active if its autocatalytic property is lost.
This will have serious consequences of initiating the growth factor of a cell affecting the chemical and physical properties of cells. The cell division and growth would be enhanced and thus the defective small G-proteins like Ras have a tendency to cause various cancers.
Hence, when the Ras protein synthesis is needed, the cell will synthesize this protein to enhance growth and metabolisms of the cell. When the Ras protein had performed its function and if there is no more requirements, then its high concentration gives feedback signal to the cell to stop its synthesis. The protein might get inactivated after that.
This feedback response by the protein for inhibiting its further synthesis is termed as the autocatalytic property. When the autocatalytic property of such protein is lost, then these proteins remains activated leading to various disorders and thus results in cancer or other fatal conditions.