Has an important role in stress fiber formation induced by active diaphanous protein homolog 1 (DRF1) (By similarity). Induces microspike formation, in vivo. In vitro, stimulates N-WASP-induced ARP2/3 complex activation in the absence of CDC42. May play an important role in the maintenance of sarcomere and/or in the assembly of myofibrils into sarcomeres. Implicated in regulation of actin polymerization and cell adhesion. Associates with the intermediate filaments, vimentin and desmin (By similarity). Binds the first and third SH3 domains of NCK (By similarity). Binds the proline-rich domains of N-WASP through its SH3 domain. Similarly, binds diaphanous protein homolog 1 (DRF1) (By similarity). Binds the SH3 domains of GRB2 through its proline-rich domains. Interacts with FASLG (By similarity). Colocalizes with DRF1 at membrane ruffles, and with Nck at Z-disks in mature cardiac myocytes.