Activates CDC42, a member of the Ras-like family of Rho- and Rac proteins, by exchanging bound GDP for free GTP. Plays a role in regulating the actin cytoskeleton and cell shape. Activates MAPK8 (By similarity).
Subcellular locations: Cytoplasm, Cytoskeleton, Cell projection, Filopodium
Concentrated in filopodia and poorly detected at lamellipodia. Binds along the sides of actin fibers (By similarity).
Expressed in different tissues, including brain, cerebellum, peripheral nerve, skeletal muscle, heart, uterus, placenta and testis.