Protein phosphatase which may play a role in the regulation of actin filament dynamics. Can dephosphorylate and activate the actin binding/depolymerizing factor cofilin, which subsequently binds to actin filaments and stimulates their disassembly. H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate H2O + O-phospho-L-seryl-[protein] = L-seryl-[protein] + phosphate H2O + O-phospho-L-threonyl-[protein] = L-threonyl-[protein] + phosphate Does not bind to, or colocalize with, filamentous actin. Expressed in brain, small intestine and testis. Also expressed at lower levels in heart, kidney, liver, spleen and thymus. Expressed in the nervous system and epithelial tissues of the trachea at 14.5 dpc. Tyrosine phosphatase activity has not been demonstrated for this protein to date. Belongs to the protein-tyrosine phosphatase family.