Actin-binding protein that contains 2 major actin binding sites (PubMed:21685497, PubMed:23184945). Organizes filamentous actin into parallel bundles (PubMed:20393565, PubMed:21685497, PubMed:23184945). Plays a role in the organization of actin filament bundles and the formation of microspikes, membrane ruffles, and stress fibers (PubMed:22155786). Important for the formation of a diverse set of cell protrusions, such as filopodia, and for cell motility and migration (PubMed:20393565, PubMed:21685497, PubMed:23184945). Mediates reorganization of the actin cytoskeleton and axon growth cone collapse in response to NGF (PubMed:22155786). Interacts with RUFY3 (via N-terminus); the interaction induces neuron axon development (By similarity). Interacts with NGFR (By similarity). Associates with CTNNB1 (By similarity). Interacts with PLXNB3 (PubMed:21706053). Colocalized with RUFY3 and F-actin at filipodia of the axonal growth cone. Colocalized with DBN1 and F-actin at the transitional domain of the axonal growth cone (By similarity). Ubiquitous. Composed of four fascin beta-trefoil domains. Phosphorylation at Ser-39 inhibits actin-binding (PubMed:8647875, PubMed:8999969). Phosphorylation is required for the reorganization of the actin cytoskeleton in response to NGF (PubMed:22155786). Belongs to the fascin family. Extended N-terminus.