※ NRPTP family introduction

    Non-receptor protein phosphatase (NRPTP), also known as cytoplasmic PTPs, belong to the classical PTP with non-transmembrane structure. The phosphatase catalytic activity is control by the regulatory sequence flanking the catalytic domain through interaction at the active site that modulate activity or control substrate specificity. In addition, the regulatory sequences also control the subcellular distribution (1). NRPTP family is involved in varieties of cellular processes. For example, PTPN14 plays an important role in regulating lymphatic function and choanal development in human (2). PTPN20 is targeted to sites of actin polymerization in response of varied extracellular stimuli (3). PTPN11 participate in the signal transduction from the cell surface to nucleus and act as downstream receptor (4).

Reference
1. Tonks, N.K. (2006) Protein tyrosine phosphatases: from genes, to function, to disease. Nat Rev Mol Cell Biol, 7, 833-846 PMID: 17057753
2. Au, A.C., Hernandez, P.A., Lieber, E., Nadroo, A.M., Shen, Y.M., Kelley, K.A., Gelb, B.D. and Diaz, G.A. (2010) Protein tyrosine phosphatase PTPN14 is a regulator of lymphatic function and choanal development in humans. Am J Hum Genet, 87, 436-444. PMID: 20826270
3. Fodero-Tavoletti, M.T., Hardy, M.P., Cornell, B., Katsis, F., Sadek, C.M., Mitchell, C.A., Kemp, B.E. and Tiganis, T. (2005) Protein tyrosine phosphatase hPTPN20a is targeted to sites of actin polymerization. Biochem J, 389, 343-354. PMID: 15790311
4. Jakob, S., Schroeder, P., Lukosz, M., Buchner, N., Spyridopoulos, I., Altschmied, J. and Haendeler, J. (2008) Nuclear protein tyrosine phosphatase Shp-2 is one important negative regulator of nuclear export of telomerase reverse transcriptase. J Biol Chem, 283, 33155-33161. PMID: 18829466