Ras-associating (RA) domain of Ras-association domain family 5 (RASSF5)
RASSF5, also called New ras effector 1 (NORE1), or regulator for cell adhesion and polarization enriched in lymphoid tissues (RAPL), is a member of a family of six related RASSF1-6 proteins (the classical RASSF proteins) and is expressed as three transcripts (A-C) via differential promoter usage and alternative splicing. All transcripts variants of RASSF5 contain the RA or SARAH domains. The RA domain of the classical RASSF proteins has a beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin. The RA domain mediates interactions with Ras and other small GTPases, and the SARAH domain mediates protein-protein interactions crucial in the pathways that induce cell cycle arrest and apoptosis. RASSF5A is a pro-apoptotic Ras effector and functions as a Ras regulated tumor suppressor. RASSF5C is regulated by Ras related protein and modulates cellular adhesion.