Ras-related protein Ral-B (RALB) is a member of a subfamily of Ras-related GTPases. RALB is activated by a unique nucleotide exchange factor, Ral GDS, and deactivated by a distinct GTPase-activating protein. RALB has a role in the late stages of cytokinesis and is required for the abscission of the bridge joining the sister cells emerging from mitosis. In addition, RALB is required for suppression of apoptosis.