Protein tyrosine phosphatase which stimulates progression from G1 into S phase during mitosis. May play a role in the development and maintenance of differentiating epithelial tissues (By similarity). H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate Inhibited by sodium orthovanadate and pentamidine. Homotrimer. Interacts with ATF5 and tubulin (By similarity). And mitotic spindle. Brain (neurons and oligodendrocytes), skeletal muscle, regenerating liver, tumor cell lines. Expressed in enterocytes of the small intestine villi and colonic surface, zymogen cells of the stomach, proximal tubule cells of the kidney, bronchiolar epithelium, but not in esophagus and heart (at protein level). Expressed in fetal brain. Up-regulated during oligodendroglial differentiation. Expressed in the developing intestine, esophagus, liver, kidney and lung (at protein level). By hepatectomy, mitogens, and ischemia-reperfusion. Farnesylated. Farnesylation is required for membrane targeting (By similarity). Belongs to the protein-tyrosine phosphatase family.