Abl2/Abl-related gene stabilizes actin filaments, stimulates actin branching by actin-related protein 2/3 complex, and promotes actin filament severing by cofilin

Background: Arg/Abl2 has two actin-binding domains, but how they influence actin filaments was unknown. Results: Arg and cortactin cooperatively stabilize actin filaments; Arg enhances Arp2/3 complex activation and stimulates severing by cofilin. Conclusion: Arg directly regulates actin filament stability, branching, and severing, which are modulated by cortactin. Significance: These activities may underlie the control of actin-based cellular structures by Arg.