SOS (Son of Sevenless)

SOS (Son of Sevenless) is a protein found in cells that acts as a crucial part of a signaling pathway controlling cell growth and division. It functions as a guanine nucleotide exchange factor (GEF), activating another protein called Ras by helping it switch from an inactive to an active state. When Ras is active, it triggers a cascade of signals that promote cell proliferation and survival. SOS is essential for transmitting signals from cell surface receptors to inside the cell, ensuring proper responses to external cues. Its proper function is vital for normal cell behavior, and disruptions can lead to issues like uncontrolled cell growth.