Plays a role in the generation of neuronal polarity formation and axon growth (By similarity). Implicated in the formation of a single axon by developing neurons (By similarity). May inhibit the formation of additional axons by inhibition of PI3K in minor neuronal processes (By similarity). Plays a role in the formation of F-actin-enriched protrusive structures at the cell periphery (PubMed:25766321). Plays a role in cytoskeletal organization by regulating the subcellular localization of FSCN1 and DBN1 at axonal growth cones (By similarity). Promotes gastric cancer cell migration and invasion in a PAK1-dependent manner (PubMed:25766321). Interacts with PAK1 (PubMed:25766321). Interacts (via C-terminus) with Ras-related Rab-5 proteins (PubMed:20376209). Interacts (via C-terminus) with Ras-related Rap-2 proteins (PubMed:20376209). Interacts with PIK3CA and PIK3R1 (By similarity). Interacts (via N-terminus) with FSCN1; this interaction induces neuron axon development (By similarity). Interacts with DBN1 (By similarity). Colocalizes with PAK1, F-actin, myosins and integrins in invadopodia at the cell periphery (PubMed:25766321). Colocalized with Ras-related Rab-5 proteins in cytoplasmic vesicles (PubMed:20376209). Accumulates in axon growth cones in a F-actin-dependent manner (By similarity). Colocalized with FSCN1 and F-actin at filipodia and lamellipodia of axonal growth cones (By similarity). Colocalized with DBN1 and F-actin at transitional domain of the axonal growth cone (By similarity). Overexpressed in gastric cancer cells and tissues (at protein level) (PubMed:25766321). Phosphorylated by PAK1 (PubMed:25766321). Isoform 1 is partially phosphorylated (By similarity). Extended N-terminus.