title: Expression, localization, and biological function of the R3 subtype of receptor-type protein tyrosine phosphatases in mammals.
abstract: The R3 subtype of receptor-type protein tyrosine phosphatases (RPTPs) includes VE-PTP, DEP-1, PTPRO, and SAP-1. All of these enzymes share a similar structure, with a single catalytic domain and putative tyrosine phosphorylation sites in the cytoplasmic region and fibronectin type III-like domains in the extracellular region. The expression of each R3 RPTP is largely restricted to a single or limited number of cell types, with VE-PTP and DEP-1 being expressed in endothelial or hematopoietic cells, PTPRO in neurons and in podocytes of the renal glomerulus, and SAP-1 in gastrointestinal epithelial cells. In addition, these RPTPs are localized specifically at the apical surface of polarized cells. The structure, expression, and localization of the R3 RPTPs suggest that they perform tissue-specific functions and that they might act through a common mechanism that includes activation of Src family kinases. In this review, we describe recent insights into R3-subtype RPTPs, particularly those of mammals.
authors.affiliation: Laboratory of Biosignal Sciences, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-Machi, Maebashi, Gunma 371-8512, Japan. matozaki@showa.gunma-u.ac.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Matozaki
authors.forename: Yoji
authors.initials: Y
authors.lastname: Murata
authors.forename: Munemasa
authors.initials: M
authors.lastname: Mori
authors.forename: Takenori
authors.initials: T
authors.lastname: Kotani
authors.forename: Hideki
authors.initials: H
authors.lastname: Okazawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohnishi
mesh_terms: D000818:Animals; D020134:Catalytic Domain; D042783:Endothelial Cells / Q000378:metabolism; D005353:Fibronectins / Q000378:metabolism; D008322:Mammals / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D017434:Protein Structure, Tertiary; D054631:Receptor-Like Protein Tyrosine Phosphatases, Class 3 / Q000378:metabolism* / Q000502:physiology; D019061:src-Family Kinases / Q000378:metabolism
chemical_list: D005353:Fibronectins; D019061:src-Family Kinases; D054631:Receptor-Like Protein Tyrosine Phosphatases, Class 3