Overview

Reversible protein tyrosine phosphorylation is a prominent mechanism utilized in controlling these signalling pathways: protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs) co-ordinately determine the tyrosine phosphorylation status and the function of a particular substrate protein. Perturbations of such signalling pathways underlie a variety of pathological conditions. Aberrant tyrosine phosphorylation due to malfunctioning PTKs is well established as the basis of several human diseases, in particular human cancers. It is becoming apparent that defective or deregulated PTPs are likewise critical in the development and progression of some human diseases such as cancer and diabetes. Consequently, PTPs are excellent targets for disease intervention.

Publications

PTPa is required for laminin-2-induced Fyn–Akt signaling to drive oligodendrocyte differentiation
Journal of Cell Science
Philip T. T. Ly, Craig Stewart, Catherine J. Pallen
DOI: 10.1242/jcs.212076
08/2018

The Interaction of Protein-tyrosine Phosphatase a (PTPa) and RACK1 Protein Enables Insulin-like Growth Factor 1 (IGF-1)-stimulated Abl-dependent and -independent Tyrosine Phosphorylation of PTPa
J. Biol. Chem.
Ranvikram S. Khanna, Hoa T. Le, Jing Wang, Thomas C. H. Fung, Catherine J. Pallen
DOI: 10.1074/jbc.m114.624247
02/2015

The Interaction of protein-tyrosine phosphatasea (PTPa) and RACK1 protein enables insulin-like growth factor 1 (IGF-1)-stimulated Abl-dependent and -independent tyrosine phosphorylation of PTPa
Journal of Biological Chemistry
Khanna, R.S. and Le, H.T. and Wang, J. and Fung, T.C.H. and Pallen, C.J.
DOI: 10.1074/jbc.M114.624247
2015

Protein Tyrosine Phosphatases in Mast Cell Signaling
Mast Cells
Alexander Geldman, Catherine J. Pallen
DOI: 10.1007/978-1-4939-1568-2_17
09/2014

Grb2 Promotes integrin-induced focal adhesion kinase (FAK) autophosphorylation and directs the phosphorylation of protein tyrosine phosphatase a by the src-FAK kinase complex
Molecular and Cellular Biology
Cheng, S.Y.S. and Sun, G. and Schlaepfer, D.D. and Pallen, C.J.
DOI: 10.1128/MCB.00825-13
2014

Tyrosine phosphatase PTPa contributes to HER2-evoked breast tumor initiation and maintenance
Oncogene
Meyer, D.S. and Aceto, N. and Sausgruber, N. and Brinkhaus, H. and Müller, U. and Pallen, C.J. and Bentires-Alj, M.
DOI: 10.1038/onc.2012.585
2014

Grb2 Promotes Integrin-Induced Focal Adhesion Kinase (FAK) Autophosphorylation and Directs the Phosphorylation of Protein Tyrosine Phosphatase   by the Src-FAK Kinase Complex
Molecular and Cellular Biology
S. Y. S. Cheng, G. Sun, D. D. Schlaepfer, C. J. Pallen
DOI: 10.1128/mcb.00825-13
11/2013

TDP1 and PARP1 Deficiency Are Cytotoxic to Rhabdomyosarcoma Cells
Molecular Cancer Research
H. K. Fam, C. Walton, S. A. Mitra, M. Chowdhury, N. Osborne, K. Choi, G. Sun, P. C. W. Wong, M. J. O'Sullivan, G. Turashvili, S. Aparicio, T. J. Triche, M. Bond, C. J. Pallen, C. F. Boerkoel
DOI: 10.1158/1541-7786.mcr-12-0575
08/2013

TDP1 and PARP1 deficiency are cytotoxic to rhabdomyosarcoma cells
Molecular Cancer Research
Fam, H.K. and Walton, C. and Mitra, S.A. and Chowdhury, M. and Osborne, N. and Choi, K. and Sun, G. and Wong, P.C.W. and O'Sullivan, M.J. and Turashvili, G. and Aparicio, S. and Triche, T.J. and Bond, M. and Pallen, C.J. and Boerkoel, C.F.
DOI: 10.1158/1541-7786.MCR-12-0575
2013

Protein Tyrosine Phosphatase   Phosphotyrosyl-789 Binds BCAR3 To Position Cas for Activation at Integrin-Mediated Focal Adhesions
Molecular and Cellular Biology
G. Sun, S. Y. S. Cheng, M. Chen, C. J. Lim, C. J. Pallen
DOI: 10.1128/mcb.00214-12
07/2012

Loss of Protein-tyrosine Phosphatase a  (PTPa) Increases Proliferation and Delays Maturation of Oligodendrocyte Progenitor Cells
Journal of Biological Chemistry
P.-S. Wang and J. Wang and Y. Zheng and C. J. Pallen
DOI: 10.1074/jbc.m111.312769
02/2012

Protein tyrosine phosphatase a Phosphotyrosyl-789 binds BCAR3 to position cas for activation at integrin-mediated focal adhesions
Molecular and Cellular Biology
Sun, G. and Cheng, S.Y.S. and Chen, M. and Lim, C.J. and Pallen, C.J.
DOI: 10.1128/MCB.00214-12
2012

Receptor-like Protein-tyrosine Phosphatase   Enhances Cell Surface Expression of Neural Adhesion Molecule NB-3
Journal of Biological Chemistry
H. Ye, T. Zhao, Y. L. J. Tan, J. Liu, C. J. Pallen, Z.-C. Xiao
DOI: 10.1074/jbc.m110.214080
05/2011

YB-1 bridges neural stem cells and brain tumor-initiating cells via its roles in differentiation and cell growth
Cancer Research
Fotovati, A. and Abu-Ali, S. and Wang, P.-S. and Deleyrolle, L.P. and Lee, C. and Triscott, J. and Chen, J.Y. and Franciosi, S. and Nakamura, Y. and Sugita, Y. and Uchiumi, T. and Kuwano, M. and Leavitt, B.R. and Singh, S.K. and Jury, A. and Jones, C. and Wakimoto, H. and Reynolds, B.A. and Pallen, C.J. and Dunn, S.E.
DOI: 10.1158/0008-5472.CAN-10-2805
2011

Receptor-like protein-tyrosine phosphatase a enhances cell surface expression of neural adhesion molecule NB-3
Journal of Biological Chemistry
Ye, H. and Zhao, T. and Tan, Y.L.J. and Liu, J. and Pallen, C.J. and Xiao, Z.-C.
DOI: 10.1074/jbc.M110.214080
2011

PTPa activates Lyn and Fyn and suppresses Hck to negatively regulate FceRI-dependent mast cell activation and allergic responses
Journal of Immunology
Samayawardhena, L.A. and Pallen, C.J.
DOI: 10.4049/jimmunol.1001261
2010

Small interfering RNA library screen of human kinases and phosphatases identifies polo-like kinase 1 as a promising new target for the treatment of pediatric rhabdomyosarcomas
Molecular Cancer Therapeutics
K. Hu, C. Lee, D. Qiu, A. Fotovati, A. Davies, S. Abu-Ali, D. Wai, E. R. Lawlor, T. J. Triche, C. J. Pallen, S. E. Dunn
DOI: 10.1158/1535-7163.mct-09-0365
11/2009

Protein-tyrosine Phosphatase   Acts as an Upstream Regulator of Fyn Signaling to Promote Oligodendrocyte Differentiation and Myelination
Journal of Biological Chemistry
P.-S. Wang, J. Wang, Z.-C. Xiao, C. J. Pallen
DOI: 10.1074/jbc.m109.061770
10/2009

Small interfering RNA library screen of human kinases and phosphatases identifies polo-like kinase 1 as a promising new target for the treatment of pediatric rhabdomyosarcomas
Molecular Cancer Therapeutics
Hu, K. and Lee, C. and Qiu, D. and Fotovati, A. and Davies, A. and Abu-Ali, S. and Wai, D. and Lawlor, E.R. and Triche, T.J. and Pallen, C.J. and Dunn, S.E.
DOI: 10.1158/1535-7163.MCT-09-0365
2009

Protein-tyrosine phosphatase a acts as an upstream regulator of Fyn signaling to promote oligodendrocyte differentiation and myelination
Journal of Biological Chemistry
Wang, P.-S. and Wang, J. and Xiao, Z.-C. and Pallen, C.J.
DOI: 10.1074/jbc.M109.061770
2009

Protein tyrosine phosphatase-a complexes with the IGF-I receptor and undergoes IGF-I-stimulated tyrosine phosphorylation that mediates cell migration
American Journal of Physiology - Cell Physiology
Chen, S.C. and Khanna, R.S. and Bessette, D.C. and Samayawardhena, L.A. and Pallen, C.J.
DOI: 10.1152/ajpcell.00110.2009
2009

Protein-tyrosine Phosphatase   Regulates Stem Cell Factor-dependent c-Kit Activation and Migration of Mast Cells
Journal of Biological Chemistry
L. A. Samayawardhena, C. J. Pallen
DOI: 10.1074/jbc.m804077200
08/2008

Neural recognition molecules CHL1 and NB-3 regulate apical dendrite orientation in the neocortex via PTPa
EMBO Journal
Ye, H. and Tan, Y.L.J. and Ponniah, S. and Takeda, Y. and Wang, S.-Q. and Schachner, M. and Watanabe, K. and Pallen, C.J. and Xiao, Z.-C.
DOI: 10.1038/sj.emboj.7601939
2008

Distinct FAK-Src activation events promote a5ß1 and a4ß1 integrin-stimulated neuroblastoma cell motility
Oncogene
Wu, L. and Bernard-Trifilo, J.A. and Lim, Y. and Lim, S.-T. and Mitra, S.K. and Uryu, S. and Chen, M. and Pallen, C.J. and Cheung, N.-K.V. and Mikolon, D. and Mielgo, A. and Stupack, D.G. and Schlaepfer, D.D.
DOI: 10.1038/sj.onc.1210770
2008

Breaking the pain connection
Nature Medicine
Pallen, C.J.
DOI: 10.1038/nm1208-1313
2008

Protein-tyrosine phosphatase a regulates stem cell factor-dependent c-Kit activation and migration of mast cells
Journal of Biological Chemistry
Samayawardhena, L.A. and Pallen, C.J.
DOI: 10.1074/jbc.M804077200
2008

PRL PTPs: Mediators and markers of cancer progression
Cancer and Metastasis Reviews
Bessette, D.C. and Qiu, D. and Pallen, C.J.
DOI: 10.1007/s10555-008-9121-3
2008

Differential Function of PTP  and PTP  Y789F in T Cells and Regulation of PTP  Phosphorylation at Tyr-789 by CD45
Journal of Biological Chemistry
L. Maksumova, Y. Wang, N. K. Y. Wong, H. T. Le, C. J. Pallen, P. Johnson
DOI: 10.1074/jbc.m703157200
05/2007

Ewing sarcoma with novel translocation t(2;16) producing an in-flame fusion of FUS and FEV
Journal of Molecular Diagnostics
Ng, T.L. and O'Sullivan, M.J. and Pallen, C.J. and Hayes, M. and Clarkson, P.W. and Winstanley, M. and Sorensen, P.H.B. and Nielsen, T.O. and Horsman, D.E.
DOI: 10.2353/jmoldx.2007.070009
2007

Differential function of PTPa and PTPa Y789F in T cells and regulation of PTPa phosphorylation at Tyr-789 by CD45
Journal of Biological Chemistry
Maksumova, L. and Wang, Y. and Wong, N.K.Y. and Le, H.T. and Pallen, C.J. and Johnson, P.
DOI: 10.1074/jbc.M703157200
2007

PRL-3: A metastasis-associated phosphatase in search of a function
Cells Tissues Organs
Bessette, D.C. and Wong, P.C.W. and Pallen, C.J.
DOI: 10.1159/000101324
2007

Integrin-induced Tyrosine Phosphorylation of Protein-tyrosine Phosphatase-  Is Required for Cytoskeletal Reorganization and Cell Migration
Journal of Biological Chemistry
M. Chen, S. C. Chen, C. J. Pallen
DOI: 10.1074/jbc.m600561200
02/2006

Reduced NMDA receptor tyrosine phosphorylation in PTPa-deficient mouse synaptosomes is accompanied by inhibition of four src family kinases and Pyk2: An upstream role for PTPa in NMDA receptor regulation
Journal of Neurochemistry
Le, H.T. and Maksumova, L. and Wang, J. and Pallen, C.J.
DOI: 10.1111/j.1471-4159.2006.04075.x
2006

Differential effects of interleukin-1ß and transforming growth factor-ß1 on the expression of the inflammation-associated protein, ADAMTS-1, in human decidual stromal cells in vitro
Human Reproduction
Ng, Y.H. and Zhu, H. and Pallen, C.J. and Leung, P.C.K. and MacCalman, C.D.
DOI: 10.1093/humrep/del108
2006

Integrin-induced tyrosine phosphorylation of protein-tyrosine phosphatase-a is required for cytoskeletal reorganization and cell migration
Journal of Biological Chemistry
Chen, M. and Chen, S.C. and Pallen, C.J.
DOI: 10.1074/jbc.M600561200
2006

Protein tyrosine phosphatase a regulates Fyn activity and Cbp/PAG phosphorylation in thymocyte lipid rafts
Journal of Immunology
Maksumova, L. and Le, H.T. and Muratkhodjaev, F. and Davidson, D. and Veillette, A. and Pallen, C.J.
2005

Akt phosphorylates the Y-box binding protein 1 at Ser102 located in the cold shock domain and affects the anchorage-independent growth of breast cancer cells
Oncogene
Sutherland, B.W. and Kucab, J. and Wu, J. and Lee, C. and Cheang, M.C.U. and Yorida, E. and Turbin, D. and Dedhar, S. and Nelson, C. and Pollak, M. and Grimes, H.L. and Miller, K. and Badve, S. and Huntsman, D. and Blake-Gilks, C. and Chen, M. and Pallen, C.J. and Dunn, S.E.
DOI: 10.1038/sj.onc.1208590
2005

Insulin signaling and glucose homeostasis in mice lacking protein tyrosine phosphatase a
Biochemical and Biophysical Research Communications
Le, H.T. and Ponniah, S. and Pallen, C.J.
DOI: 10.1016/j.bbrc.2003.12.087
2004

Protein Tyrosine Phosphatase α (PTPα): A Src Family Kinase Activator and Mediator of Multiple Biological Effects
CTMC
Catherine Pallen
DOI: 10.2174/1568026033452320
03/2003

Nogo-A at CNS paranodes is a ligand of Caspr: Possible regulation of K + channel localization
EMBO Journal
Nie, D.-Y. and Zhou, Z.-H. and Ang, B.-T. and Teng, F.Y.H. and Xu, G. and Xiang, T. and Wang, C.-Y. and Zeng, L. and Takeda, Y. and Xu, T.-L. and Ng, Y.-K. and Faivre-Sarrailh, C. and Popko, B. and Ling, E.-A. and Schachner, M. and Watanabe, K. and Pallen, C.J. and Tang, B.L. and Xiao, Z.-C.
DOI: 10.1093/emboj/cdg570
2003

F3/contactin acts as a functional ligand for notch during oligodendrocyte maturation
Cell
Hu, Q.-D. and Ang, B.-T. and Karsak, M. and Hu, W.-P. and Cui, X.-Y. and Duka, T. and Takeda, Y. and Chia, W. and Sankar, N. and Ng, Y.-K. and Ling, E.-A. and Maciag, T. and Small, D. and Trifonova, R. and Kopan, R. and Okano, H. and Nakafuku, M. and Chiba, S. and Hirai, H. and Aster, J.C. and Schachner, M. and Pallen, C.J. and Watanabe, K. and Xiao, Z.-C.
DOI: 10.1016/S0092-8674(03)00810-9
2003

PTPa regulates integrin-stimulated FAK autophosphorylation and cytoskeletal rearrangement in cell spreading and migration
Journal of Cell Biology
Zeng, L. and Si, X. and Yu, W.-P. and Thi Le, H. and Ng, K.P. and Teng, R.M.H. and Ryan, K. and Wang, D.Z.-M. and Ponniah, S. and Pallen, C.J.
DOI: 10.1083/jcb.200206049
2003

Protein tyrosine phosphatase alpha (PTPa) knockout mice show deficits in Morris water maze learning, decreased locomotor activity, and decreases in anxiety
Brain Research
Skelton, M.R. and Ponniah, S. and Wang, D.Z.-M. and Doetschman, T. and Vorhees, C.V. and Pallen, C.J.
DOI: 10.1016/S0006-8993(03)02839-7
2003

Protein tyrosine phosphatase alpha (PTPalpha): a Src family kinase activator and mediator of multiple biological effects.
Current topics in medicinal chemistry
Pallen, C.J.
2003

PRL-3 and PRL-1 promote cell migration, invasion, and metastasis
Cancer Research
Zeng, Q. and Dong, J.-M. and Guo, K. and Li, J. and Tan, H.-X. and Koh, V. and Pallen, C.J. and Manser, E. and Hong, W.
2003

Interaction of Farnesylated PRL-2, a Protein-tyrosine Phosphatase, with the  -Subunit of Geranylgeranyltransferase II
Journal of Biological Chemistry
X. Si, Q. Zeng, C. H. Ng, W. Hong, C. J. Pallen
DOI: 10.1074/jbc.m010400200
07/2001

Interaction of Farnesylated PRL-2, a Protein-tyrosine Phosphatase, with the ß-Subunit of Geranylgeranyltransferase II
Journal of Biological Chemistry
Si, X. and Zeng, Q. and Ng, C.H. and Hong, W. and Pallen, C.J.
DOI: 10.1074/jbc.M010400200
2001

Conserved synteny between the Fugu and human PTEN locus and the evolutionary conservation of vertebrate PTEN function
Oncogene
Yu, W.-P. and Pallen, C.J. and Tay, A. and Jirik, F.R. and Brenner, S. and Tan, Y.H. and Venkatesh, B.
DOI: 10.1038/sj.onc.1204679
2001

Calmodulin Binds to and Inhibits the Activity of the Membrane Distal Catalytic Domain of Receptor Protein-tyrosine Phosphatase  
Journal of Biological Chemistry
L. Liang, K. L. Lim, K. T. Seow, C. H. Ng, C. J. Pallen
DOI: 10.1074/jbc.m004843200
07/2000

Isolation of a novel protein tyrosine phosphatase inhibitor, 2-methyl-fervenulone, and its precursors from Streptomyces
Journal of Natural Products
Wang, H. and Kah Leong Lim, and Su Ling Yeo, and Xu, X. and Mui Mui Sim, and Ting, A.E. and Wang, Y. and Yee, S. and Tan, Y.H. and Pallen, C.J.
DOI: 10.1021/np000293+
2000

Calmodulin binds to and inhibits the activity of the membrane distal catalytic domain of receptor protein-tyrosine phosphatase a
Journal of Biological Chemistry
Liang, L. and Lim, K.L. and Seow, K.T. and Ng, C.H. and Pallen, C.J.
2000

Prenylation-dependent association of protein-tyrosine phosphatases PRL- 1, -2, and -3 with the plasma membrane and the early endosome
Journal of Biological Chemistry
Zeng, Q. and Si, X. and Horstmann, H. and Xu, Y. and Hong, W. and Pallen, C.J.
DOI: 10.1074/jbc.M000453200
2000

Targeted disruption of the tyrosine phosphatase PTPa leads to constitutive downregulation of the kinases Src and Fyn
Current Biology
Sathivel Ponniah, Dennis Z.M. Wang, Kah Leong Lim, Catherine J. Pallen
DOI: 10.1016/s0960-9822(99)80238-3
05/1999

Catalytic activation of the membrane distal domain of protein tyrosine phosphatase e, but not CD45, by two point mutations
Biochimica et Biophysica Acta - Protein Structure and Molecular Enzymology
Lim, K.L. and Ng, C.H. and Pallen, C.J.
DOI: 10.1016/S0167-4838(99)00189-2
1999

Protein tyrosine phosphatase a (PTPa) and contactin form a novel neuronal receptor complex linked to the intracellular tyrosine kinase fyn
Journal of Cell Biology
Zeng, L. and D'Alessandri, L. and Kalousek, M.B. and Vaughan, L. and Pallen, C.J.
DOI: 10.1083/jcb.147.4.707
1999

Targeted disruption of the tyrosine phosphatase PTPa leads to constitutive downregulation of the kinases Src and Fyn
Current Biology
Ponniah, S. and Wang, D.Z.M. and Kah Leong, L. and Pallen, C.J.
DOI: 10.1016/S0960-9822(99)80238-3
1999

Solid-phase synthesis of potential protein tyrosine phosphatase inhibitors via the Ugi four-component condensation
Bioorganic & Medicinal Chemistry Letters
Zhengong Li, Su Ling Yeo, Catherine J. Pallen, A. Ganesan
DOI: 10.1016/s0960-894x(98)00408-9
09/1998

Antibodies to the Protein Tyrosine Phosphatases IAR and IA-2 are Associated with Progression to Insulin-Dependent Diabetes (IDDM) in First-Degree Relatives At-Risk for IDDM
Autoimmunity
Robert S. Schmidli, Peter G. Colman, Lin Cui, Wei-Ping Yu, Kim Kewming, Connie Jankulovski, Leonard C. Harrison, Catherine J. Pallen, Henry J. Deaizpurua
DOI: 10.3109/08916939808993841
01/1998

Interconversion of the kinetic identities of the tandem catalytic domains of receptor-like protein-tyrosine phosphatase PTPa by two point mutations is synergistic and substrate-dependent
Journal of Biological Chemistry
Lim, K.L. and Kolatkar, P.R. and Ng, K.P. and Ng, C.H. and Pallen, C.J.
DOI: 10.1074/jbc.273.44.28986
1998

Solid-phase synthesis of potential protein tyrosine phosphatase inhibitors via the Ugi four-component condensation
Bioorganic and Medicinal Chemistry Letters
Li, Z. and Yeo, S.L. and Pallen, C.J. and Ganesan, A.
DOI: 10.1016/S0960-894X(98)00408-9
1998

Localization of the genes encoding the type I diabetes autoantigens, protein-tyrosine phosphatases IA2 and IAR
Mammalian Genome
Morahan, G. and Huang, D. and Yu, W.-P. and Cui, L. and DeAizpurua, H. and Pallen, C.J.
DOI: 10.1007/s003359900824
1998

Physical and functional interactions between receptor-like protein- tyrosine phosphatase a and p59(fyn)
Journal of Biological Chemistry
Bhandari, V. and Lim, K.L. and Pallen, C.J.
DOI: 10.1074/jbc.273.15.8691
1998

Antibodies to the protein tyrosine phosphatases IAR and IA-2 are associated with progression to insulin-dependent diabetes (IDDM) in first-degree relatives at-risk for IDDM
Autoimmunity
Schmidli, R.S. and Colman, P.G. and Cui, L. and Yu, W.-P. and Kewming, K. and Jankulovski, C. and Harrison, L.C. and Pallen, C.J. and Deaizpurua, H.J.
1998

Insulin secretagogues activate the secretory granule receptor-like protein-tyrosine phosphatase IAR
Journal of Biological Chemistry
Cui, L. and Yu, W.-P. and Pallen, C.J.
DOI: 10.1074/jbc.273.52.34784
1998

Kinetic analysis of two closely related receptor-like protein-tyrosine- phosphatases, PTPa and PTPe
European Journal of Biochemistry
Lim, K.L. and Lai, D.S.Y. and Kalousek, M.B. and Wang, Y. and Pallen, C.J.
1997

Cloning and characterization of islet cell antigen-related protein- tyrosine phosphatase (PTP), a novel receptor-like PTP and autoantigen in insulin-dependent diabetes
Journal of Biological Chemistry
Cui, L. and Yu, W.-P. and DeAizpurua, H.J. and Schmidli, R.S. and Pallen, C.J.
DOI: 10.1074/jbc.271.40.24817
1996

Novel alternative splicing predicts a secreted extracellular isoform of the human receptor-like protein tyrosine phosphatase LAR
Gene
Tabiti, K. and Cui, L. and Chhatwal, V.J.S. and Moochhala, S. and Ngoi, S.S. and Pallen, C.J.
DOI: 10.1016/0378-1119(96)00113-8
1996

Increased mRNA expression of the receptor-like protein tyrosine phosphatase a in late stage colon carcinomas
Cancer Letters
Karim Tabiti, Duncan R. Smith, Hak-Su Goh, Catherine J. Pallen
DOI: 10.1016/0304-3835(95)03816-f
07/1995

Increased mRNA expression of the receptor-like protein tyrosine phosphatase a in late stage colon carcinomas
Cancer Letters
Tabiti, K. and Smith, D.R. and Goh, H.-S. and Pallen, C.J.
DOI: 10.1016/0304-3835(95)03816-F
1995

Expression of receptor-like protein tyrosine phosphatase a in rat embryo fibroblasts activates mitogen-activated protein kinase and c-Jun
Journal of Biological Chemistry
Zheng, X.M. and Pallen, C.J.
1994

The receptor-like protein tyrosine phosphatase a: a role in cell proliferation and oncogenesis
Seminars in Cell Biology
Catherine J. Pallen
DOI: 10.1006/scel.1993.1048
1993

The receptor-like protein tyrosine phosphatase a: A role in cell proliferation and oncogenesis
Seminars in Cell and Developmental Biology
Pallen, C.J.
1993

Pituitary-specific transcriptional initiation sites of the rat carboxypeptidase-H gene and the influence of thyroid hormone status.
Molecular Endocrinology
D R Smith, C J Pallen, D Murphy, L Lim
DOI: 10.1210/mend.6.5.1603081
05/1992

Protein phosphatases in cell signalling
Current Opinion in Cell Biology
C PALLEN, Y TAN, G GUY
DOI: 10.1016/0955-0674(92)90132-v
1992

Protein phosphatases in cell signalling
Current Opinion in Cell Biology
Pallen, C.J. and Tan, Y.H. and Guy, G.R.
1992

Expression and characterization of wild type, truncated, and mutant forms of the intracellular region of the receptor-like protein tyrosine phosphatase HPTPß
Journal of Biological Chemistry
Wang, Y. and Pallen, C.J.
1992

Cell transformation and activation of pp60c-src by overexpression of a protein tyrosine phosphatase
Nature
Zheng, X.M. and Wang, Y. and Pallen, C.J.
1992

Pituitary-specific transcriptional initiation sites of the rat carboxypeptidase-H gene and the influence of thyroid hormone status
Molecular Endocrinology
Smith, D.R. and Pallen, C.J. and Murphy, D. and Lim, L.
1992

Elevation of membrane tyrosine phosphatase activity in density-dependent growth-arrested fibroblasts.
Proceedings of the National Academy of Sciences
C. J. Pallen, P. H. Tong
DOI: 10.1073/pnas.88.16.6996
08/1991

Purification and characterization of a higher-molecular-mass form of protein phosphotyrosine phosphatase (PTP 1B) from placental membranes
Biochem. J.
C J Pallen, D S Y Lai, H P Chia, I Boulet, P H Tong
DOI: 10.1042/bj2760315
06/1991

Purification and characterization of a higher-molecular-mass form of protein phosphotyrosine phosphatase (PTP 1B) from placental membranes
Biochemical Journal
Pallen, C.J. and Lai, D.S.Y. and Chia, H.P. and Boulet, I. and Tong, P.H.
1991

The receptor-like protein tyrosine phosphatase HPTPa has two active catalytic domains with distinct substrate specificities
EMBO Journal
Wang, V. and Pallen, C.J.
1991

Elevation of membrane tyrosine phosphatase activity in density-dependent growth-arrested fibroblasts
Proceedings of the National Academy of Sciences of the United States of America
Pallen, C.J. and Tong, P.H.
1991

Calcium-dependent and phosphorylation-stimulated proteolysis of lipocortin I by an endogenous A431 cell membrane protease
Journal of Biological Chemistry
Chuah, S.Y. and Pallen, C.J.
1989

A putative role for calmodulin in corpus cardiacum stimulated trehalose synthesis in fat body of the american cockroach (Periplaneta americana)
Insect Biochemistry
C.J. Pallen, J.E. Steele
DOI: 10.1016/0020-1790(88)90009-1
01/1988

Purification and Characterization of Placental Membrane Phosphotyrosine Phosphatases
Cold Spring Harbor Symposia on Quantitative Biology
C.J. Pallen, L. Sahlin, G. Panayotou, M.D. Waterfield
DOI: 10.1101/sqb.1988.053.01.052
01/1988

Purification of a phosphotyrosine phosphatase that dephosphorylates the epidermal growth factor receptor autophosphorylation sites
Annals of the New York Academy of Sciences
Pallen, C.J. and Panayotou, G.N. and Sahlin, L. and Waterfield, M.D.
1988

Purification and characterization of placental membrane phosphotyrosine phosphatases
Cold Spring Harbor Symposia on Quantitative Biology
Pallen, C.J. and Sahlin, L. and Panayotou, G. and Waterfield, M.D.
1988

Conversion of a phosphoseryl/threonyl phosphatase into a phosphotyrosyl phosphatase
Biochemical Journal
Goris, J. and Pallen, C.J. and Parker, P.J. and Hermann, J. and Waterfield, M.D. and Merlevede, W.
1988

Purification of a Phosphotyrosine Phesphatase That Dephosphorylates the Epidermal Growth Factor Receptor Autophosphorylation Sites
Ann NY Acad Sci
C. J. PALLEN, G. N. PANAYOTOU, L. SAHLIN, M. D. WATERFIELD
DOI: 10.1111/j.1749-6632.1988.tb22356.x
1988

Stoichiometry and dynamic interaction of metal ion activators with calcineurin phosphatase
Journal of Biological Chemistry
Pallen, C.J. and Wang, J.H.
1986

Characterization of the phosphotyrosyl protein phosphatase activity of calmodulin-dependent protein phosphatase
Journal of Biological Chemistry
Chan, C.P. and Gallis, B. and Blumenthal, D.K. and Pallen, C.J. and Wang, J.H. and Krebs, E.G.
1986

Survey of calcineurin activity towards nonprotein compounds and identification of phosphoenol pyruvate as a substrate
Biochemical and Biophysical Research Communications
Catherine J. Pallen, Mark L. Brown, Hideki Matsui, Katherine J. Mitchell, Jerry H. Wang
DOI: 10.1016/0006-291x(85)90226-8
09/1985

Modulation of cAMP effects by Ca2+/calmodulin
Bioessays
Catherine J. Pallen, Rajendra K. Sharma, Jerry H. Wang
DOI: 10.1002/bies.950020306
03/1985

A multifunctional calmodulin-stimulated phosphatase
Archives of Biochemistry and Biophysics
Pallen, C.J. and Wang, J.H.
DOI: 10.1016/0003-9861(85)90279-6
1985

Calcineurin-phosphatase: Ni2+-binding properties
Federation Proceedings
Pallen, C.J. and Wang, J.H.
1985

The calmodulin regulatory system.
Current topics in cellular regulation
Wang, J.H. and Pallen, C.J. and Sharma, R.K. and Adachi, A.M. and Adachi, K.
1985

Use of fluorinated tyrosine phosphates to probe the substrate specificity of the low molecular weight phosphatase activity of calcineurin
Journal of Biological Chemistry
Martin, B. and Pallen, C.J. and Wang, J.H. and Graves, D.J.
1985

Calcineurin-mediated dephosphorylation of the human placental membrane receptor for epidermal growth factor urogastrone
Biochemistry
Pallen, C.J. and Valentine, K.A. and Wang, J.H. and Hollenberg, M.D.
1985

Survey of calcineurin activity towards nonprotein compounds and identification of phosphoenol pyruvate as a substrate
Biochemical and Biophysical Research Communications
Pallen, C.J. and Brown, M.L. and Matsui, H. and Mitchell, K.J. and Wang, J.H.
DOI: 10.1016/0006-291X(85)90226-8
1985

Demonstration of different metal ion-induced calcineurin conformations using a monoclonal antibody
Journal of Biological Chemistry
Matsui, H. and Pallen, C.J. and Adachi, A.-M. and Wang, J.H. and Lam, P.H.
1985

Calcineurin can dephosphorylate the epidermal growth factor receptor of human placental membrane
Federation Proceedings
Pallen, C.J. and Valentine, K.A. and Wang, J.H. and Hollenberg, M.D.
1984

A survey of calcineurin activity toward non-protein substrate
Federation Proceedings
Wang, J.H. and Pallen, C.J. and Brown, M.L. and Mitchell, K.J.
1984

Regulation of calcineurin by metal ions. Mechanism of activation by Ni2+ and an enhanced response to Ca2+/calmodulin
Journal of Biological Chemistry
Pallen, C.J. and Wang, J.H.
1984

Calmodulin-stimulated dephosphorylation of p-nitrophenyl phosphate and free phosphotyrosine by calcineurin
Journal of Biological Chemistry
Pallen, C.J. and Wang, J.W.
1983

Research

Current Project
The lab studies the molecular, cell, and whole animal biology of selected PTPs, in particular the receptor PTPa and the prenylated PRL-PTPs. Characterizing their substrates, pathways of action, regulation, and localization will shed light on their specific cellular and physiological roles, reveal linkages with human pathophysiologies, and facilitate the development of PTP-based disease therapies. We are particularly interested in the roles of PTPs in pediatric malignancies.

We have identified the transmembrane PTPa as a potential oncogene and as a physiological activator of the proto-oncogene src family kinases. We are elucidating the signal transduction and biological functions of PTPa using PTPa knockout mice and cells that we have generated. One line of study involves the role of PTPa in integrin signalling. Integrins are essential for several cell processes, including growth, migration, and survival. They are thus positioned to determine, and have indeed been implicated in, multiple aspects of cancer cell biology such as invasion and metastasis. In the absence of PTPa, integrin stimulated cell migration and spreading are defective due to impaired early and integrin-proximal signalling events. The molecular basis of these defects is under investigation. Other studies are pursuing the linkage of additional novel defects observed in the PTPa knockout mice to altered cell signalling pathways and function in neurobiology (myelination, NMDA receptor function) and immunology (T cell activation, mast cell function).

The intracellular PRL-PTPs (PRL-1, -2, -3) are closely related prenylated PTPs of unknown function. PRL-3 expression has been recently found to be upregulated in several metastatic cancers. Farnesyltransferase inhibitors (FTI) are anti-tumor agents that were originally designed to block the function of the ras oncogene product. However, in many tumors, these inhibitors act on unidentified non-ras targets. We have shown that the PRLs are potential targets of these inhibitors. FTI induces the relocalization of the PRL-PTPs from the plasma membrane and early endosome to the nucleus, with the likely consequence of altering substrate availability and/or PRL-PTP functions. Our studies are directed to identifying plasma membrane/early endosome-specific versus nuclear-specific PRL-PTP substrates and interacting proteins. This will pinpoint alternate PRL-PTP functions and signalling pathways that may be relevant to tumorigenesis or tumor progression. Additionally, we are examining PRL-PTP expression in a range of primary and metastatic tumors to ascertain whether altered PRL-PTP levels correlate with malignancy status.

Grants

Cancer Research Society Grant

Honours & Awards

National Science Award, Singapore - 1995

MacMillan Distinguished Lecturer, Rutgers University - 2000

Outstanding University Researcher Award 1999/2000, National University of Singapore - 2001

Research Group Members

Gina Teodosio
Jing Wang, Lab Manager
Lisa Decotret, Masters Student