Cytoplasmic protein tyrosine phosphatases, regulation and function: the roles of PTP1B and TC-PTP.
PTP1B and TC-PTP are closely related protein tyrosine phosphatases, sharing 74% homology in their catalytic domain. However, their cellular localization, function, and regulation are found to be different. Their substrate specificity has implicated these enzymes in various signaling pathways, regulating metabolism, proliferation and cytokine signaling. For instance, PTP1B has been shown to regulate the activation of cytokine receptors through the dephosphorylation of specific members of the JAK family, namely JAK2 and TYK2, whereas TC-PTP is involved in the modulation of cytokine signaling via JAK1 and JAK3 molecules. Gene-targeting approaches will help us to unravel the physiological functions of these enzymes.
Bourdeau
Annie
A
McGill Cancer Centre, McGill University, 3655 Promenade Sir-William-Osler, room 701, Montreal, QC, H3G 1Y6, Canada.
Dubé
Nadia
N
Tremblay
Michel L
ML
D000818:Animals; D016207:Cytokines / Q000378:metabolism; D003593:Cytoplasm / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D053613:Janus Kinase 1; D053614:Janus Kinase 2; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D054578:Protein Tyrosine Phosphatase, Non-Receptor Type 2; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D018121:Receptors, Cytokine / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*
D016207:Cytokines; D047908:Intracellular Signaling Peptides and Proteins; D011518:Proto-Oncogene Proteins; D018121:Receptors, Cytokine; D011505:Protein-Tyrosine Kinases; C507904:JAK1 protein, human; C507924:JAK2 protein, human; D053613:Janus Kinase 1; D053614:Janus Kinase 2; C516607:PTPN1 protein, human; C516649:PTPN2 protein, human; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D054578:Protein Tyrosine Phosphatase, Non-Receptor Type 2; D017027:Protein Tyrosine Phosphatases