May be a regulator of cytoskeletal organization (Potential). May have a role in spermatogenesis. Interacts with WASL, and monomeric and filamentous actin. In hippocampal neurons colocalizes with WASL in the cell body, axons and the growth cone (By similarity). Localizes to the actin filaments at the Sertoli cell-spermatid junctions. Isoform 1 is expressed in brain and testis and isoform 2 is expressed only in brain (at protein level). The WH2 domain is found in a number of putative actin-binding proteins. The profilin-binding motif has been implicated in the interaction with profilin and SH3 domains. The KLKR motif is essential for G-actin binding and for actin polymerization. Mice are normal but males are sterile due to defects in spermatogenesis.