C-terminal SARAH domain found in Ras-association domain-containing protein 4 (RASSF4)
RASSF4 is one of six related proteins, the classical RASSF proteins (RASSF1-6), that contain a conserved RalGDS/AF6 Ras association (RA) domain located towards the C-terminus. It acts as a potential tumor suppressor that may promote apoptosis and cell cycle arrest. It also functions as a KRAS effector protein. RASSF4 is broadly expressed in normal tissues. Its expression is reduced in tumor cell lines and primary tumors by promoter specific hypermethylation. RASSF4 contains the RA and SARAH (Salvador-RassF-Hippo) domains. The RA domain of the classical RASSF proteins has a beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin. RA domains mediate interactions with Ras and other small GTPases, and SARAH domains mediate protein-protein interactions crucial in the pathways that induce cell cycle arrest and apoptosis. This model corresponds to the SARAH domain of RASSF4.
Jiyao W et al.(2023). "The conserved domain database in 2023.",