Induces disassembly of actin filaments in conjunction with ADF/cofilin family proteins (PubMed:15629458, PubMed:27557945, PubMed:29751004). Enhances cofilin-mediated actin severing (By similarity). Involved in cytokinesis. Involved in chemotactic cell migration by restricting lamellipodial membrane protrusions (PubMed:18494608). Involved in myocardium sarcomere organization. Required for cardiomyocyte growth and maintenance (By similarity). Involved in megakaryocyte maturation and platelet shedding. Required for the establishment of planar cell polarity (PCP) during follicular epithelium development and for cell shape changes during PCP; the function seems to implicate cooperation with CFL1 and/or DSTN/ADF. Involved in the generation/maintenance of cortical tension (By similarity). Involved in assembly and maintenance of epithelial apical cell junctions and plays a role in the organization of the perijunctional actomyosin belt (PubMed:25792565). Expressed in peripheral blood mononuclear cells (at protein level). The disease is caused by variants affecting the gene represented in this entry. Belongs to the WD repeat AIP1 family. Aberrant splicing.