GTPase-activating protein (GAP) promoting GTP hydrolysis on RHOA, CDC42 and RAC1 small GTPases. May be involved in the differentiation of neuronal cells during the formation of neurite extensions. Involved in NMDA receptor activity-dependent actin reorganization in dendritic spines. May mediate cross-talks between Ras- and Rho-regulated signaling pathways in cell growth regulation. Isoform 2 has higher GAP activity (By similarity).
Subcellular locations: Postsynaptic density, Cell projection, Dendritic spine, Cytoplasm, Cell cortex, Endosome membrane, Golgi apparatus membrane, Endoplasmic reticulum membrane, Membrane
Association to membrane via PX domain . Associated with cortical actin in undifferentiated neuroblastoma cells, but localized to dendritic spine and postsynaptic density after differentiation (By similarity). Colocalizes with EGFR at the cell membrane upon EGF treatment . Colocalizes with GAB2 at the cell membrane .
Isoform 1 and isoform 2 are highly expressed in brain and testis. Isoform 1 is also expressed in other tissues such as lung, liver and spleen.