Functions as an adapter molecule that links other proteins to the actin cytoskeleton. May function in facilitating interactions between SRC and actin filaments. May modulate changes in actin filament integrity and induce lamellipodia formation. Can cross-link actin filaments into both network and bundle structures. Monomer and homomultimer. Interacts via its C-terminus with F-actin; probably involving AFAP1 multimers. Interacts with activated SRC SH3-SH2 domains. May interact with FYN SH3-SH2 domains. Interacts via its PH 1 domain with PRKCA, PRKCB, PRKCI. Isoform 2 is specifically expressed in brain. Phosphorylated on tyrosine residues by SRC.