May play a role in the regulation of cell morphology and cytoskeletal organization (By similarity). Binds to F-actin and exhibits pH-sensitive F-actin depolymerizing activity. Required for formation of the cleavage furrow during cytokinesis. Cellular localization varies throughout development and may be related to phosphorylation levels. Shows diffuse cortical cytoplasm localization in oocytes, with membrane-association increasing after fertilization, particularly in the vegetal hemisphere (By similarity). Inactive when phosphorylated. Phosphorylation levels vary during development. Dephosphorylated by pdxp (By similarity). Belongs to the actin-binding proteins ADF family.