The Experts below are selected from a list of 5322 Experts worldwide ranked by ideXlab platform
Johan Lennartsson - One of the best experts on this subject based on the ideXlab platform.
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dual specificity phosphatase dusp 4 is induced by platelet derived growth factor bb in an erk1 2 stat3 and p53 dependent manner
Biochemical and Biophysical Research Communications, 2019Co-Authors: Glenda Eger, Niki Sarri, Charlotte Rorsman, Johan LennartssonAbstract:Abstract Dual specificity phosphatase (DUSP) 4 has been described as a negative regulator of MAP kinase signaling, in particular for the ERK1/2 and JNK pathways. We found that DUSP4 expression was upregulated in response to prolonged platelet-derived growth factor (PDGF)-BB stimulation. The PDGF-BB-induced DUSP4 expression was dependent on ERK1/2, STAT3 and p53. We found that inhibition of ERK1/2 effectively reduced DUSP4 mRNA levels, whereas STAT3 was necessary for maintaining p53 expression. p53 has binding sites in the DUSP4 promoter and was found to promote DUSP4 expression.
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dual specificity phosphatase dusp 4 is induced by platelet derived growth factor bb in an erk1 2 stat3 and p53 dependent manner
Biochemical and Biophysical Research Communications, 2019Co-Authors: Glenda Eger, Niki Sarri, Charlotte Rorsman, Johan Lennartsson, Carlhenrik HeldinAbstract:Abstract Dual specificity phosphatase (DUSP) 4 has been described as a negative regulator of MAP kinase signaling, in particular for the ERK1/2 and JNK pathways. We found that DUSP4 expression was upregulated in response to prolonged platelet-derived growth factor (PDGF)-BB stimulation. The PDGF-BB-induced DUSP4 expression was dependent on ERK1/2, STAT3 and p53. We found that inhibition of ERK1/2 effectively reduced DUSP4 mRNA levels, whereas STAT3 was necessary for maintaining p53 expression. p53 has binding sites in the DUSP4 promoter and was found to promote DUSP4 expression.
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Expression of protein-tyrosine phosphatases in Acute Myeloid Leukemia cells: FLT3 ITD sustains high levels of DUSP6 expression
Cell Communication and Signaling, 2012Co-Authors: Deepika Arora, Susanne Köthe, Monique Van Den Eijnden, Rob Hooft Van Huijsduijnen, Florian Heidel, Thomas Fischer, Sebastian Scholl, Benjamin Tölle, Sylvia-annette Böhmer, Johan LennartssonAbstract:Protein-tyrosine phosphatases (PTPs) are important regulators of cellular signaling and changes in PTP activity can contribute to cell transformation. Little is known about the role of PTPs in Acute Myeloid Leukemia (AML). The aim of this study was therefore to establish a PTP expression profile in AML cells and to explore the possible role of FLT3 ITD (Fms-like tyrosine kinase 3 with internal tandem duplication), an important oncoprotein in AML for PTP gene expression. PTP mRNA expression was analyzed in AML cells from patients and in cell lines using a RT-qPCR platform for detection of transcripts of 92 PTP genes. PTP mRNA expression was also analyzed based on a public microarray data set for AML patients. Highly expressed PTPs in AML belong to all PTP subfamilies. Very abundantly expressed PTP genes include PTPRC, PTPN2, PTPN6, PTPN22, DUSP1, DUSP6, DUSP10, PTP4A1, PTP4A2, PTEN, and ACP1 . PTP expression was further correlated with the presence of FLT3 ITD, focusing on a set of highly expressed dual-specificity phosphatases (DUSPs). Elevated expression of DUSP6 in patients harboring FLT3 ITD was detected in this analysis. The mechanism and functional role of FLT3 ITD-mediated upregulation of DUSP6 was then explored using pharmacological inhibitors of FLT3 ITD signal transduction and si/shRNA technology in human and murine cell lines. High DUSP6 expression was causally associated with the presence of FLT3 ITD and dependent on FLT3 ITD kinase activity and ERK signaling. DUSP6 depletion moderately increased ERK1/2 activity but attenuated FLT3 ITD-dependent cell proliferation of 32D cells. In conclusion, DUSP6 may play a contributing role to FLT3 ITD-mediated cell transformation.
Sabah N A Hussain - One of the best experts on this subject based on the ideXlab platform.
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regulation of angiopoietin 1 tie 2 receptor signaling in endothelial cells by dual specificity phosphatases 1 4 and 5
Journal of the American Heart Association, 2013Co-Authors: Raquel Echavarria, Sabah N A HussainAbstract:Background Angiopoietin-1 (Ang-1) promotes survival and migration of endothelial cells, in part through the activation of mitogen-activated protein kinase (MAPK) pathways downstream of Tie-2 receptors. Dual-specificity phosphatases (DUSPs) dephosphorylate phosphotyrosine and phosphoserine/phosphothreonine residues on target MAPKs. The mechanisms by which DUSPs modulate MAPK activation in Ang-1/Tie-2 receptor signaling are unknown in endothelial cells. Methods and Results Expression of various DUSPs in human umbilical vein endothelial cells exposed to Ang-1 was measured. The functional roles of DUSPs in Ang-1-induced regulation of MAPK activation, endothelial cell survival, migration, differentiation, and permeability were measured using selective siRNA oligos. Ang-1 differentially induces DUSP1, DUSP4, and DUSP5 in human umbilical vein endothelial cells through activation of the PI-3 kinase, ERK1/2, p38, and SAPK/JNK pathways. Lack-of-function siRNA screening revealed that DUSP1 preferentially dephosphorylates p38 protein and is involved in Ang-1-induced cell migration and differentiation. DUSP4 preferentially dephosphorylates ERK1/2, p38, and SAPK/JNK proteins and, under conditions of serum deprivation, is involved in Ang-1-induced cell migration, several antiapoptotic effects, and differentiation. DUSP5 preferentially dephosphorylates ERK1/2 proteins and is involved in cell survival and inhibition of permeability. Conclusions DUSP1, DUSP4, and DUSP5 differentially modulate MAPK signaling pathways downstream of Tie-2 receptors, thus highlighting the importance of these phosphatases to Ang-1-induced angiogenesis.
Stephen M Keyse - One of the best experts on this subject based on the ideXlab platform.
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dual specificity phosphatase 5 controls the localized inhibition propagation and transforming potential of erk signaling
Proceedings of the National Academy of Sciences of the United States of America, 2017Co-Authors: Andrew M Kidger, Linda K Rushworth, Christopher J Bryant, Edward Caddye, Jane Davidson, Stephen M Keyse, Julia Stellzig, Cassidy Bayley, Tim Rogers, Christopher J CauntAbstract:Deregulated extracellular signal-regulated kinase (ERK) signaling drives cancer growth. Normally, ERK activity is self-limiting by the rapid inactivation of upstream kinases and delayed induction of dual-specificity MAP kinase phosphatases (MKPs/DUSPs). However, interactions between these feedback mechanisms are unclear. Here we show that, although the MKP DUSP5 both inactivates and anchors ERK in the nucleus, it paradoxically increases and prolongs cytoplasmic ERK activity. The latter effect is caused, at least in part, by the relief of ERK-mediated RAF inhibition. The importance of this spatiotemporal interaction between these distinct feedback mechanisms is illustrated by the fact that expression of oncogenic BRAFV600E, a feedback-insensitive mutant RAF kinase, reprograms DUSP5 into a cell-wide ERK inhibitor that facilitates cell proliferation and transformation. In contrast, DUSP5 deletion causes BRAFV600E-induced ERK hyperactivation and cellular senescence. Thus, feedback interactions within the ERK pathway can regulate cell proliferation and transformation, and suggest oncogene-specific roles for DUSP5 in controlling ERK signaling and cell fate.
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regulation of the inducible nuclear dual specificity phosphatase dusp5 by erk mapk
Cellular Signalling, 2009Co-Authors: Anna Kucharska, Linda K Rushworth, Christopher J. Staples, Nicholas A. Morrice, Stephen M KeyseAbstract:Abstract DUSP5 is an inducible, nuclear, dual-specificity phosphatase, which specifically interacts with and inactivates the ERK1/2 MAP kinases in mammalian cells. In addition, expression of DUSP5 causes nuclear translocation of ERK2 indicating that it may act as a nuclear anchor for the inactive kinase. Here we show that induction of DUSP5 mRNA and protein in response to growth factors is dependent on ERK1/2 activation and that the accumulation of DUSP5 protein is regulated by rapid proteasomal degradation. DUSP5 is phosphorylated by ERK1/2 both in vitro and in vivo on three sites (Thr321, Ser346 and Ser376) within its C-terminal domain. DUSP5 phosphorylation is absolutely dependent on the conserved kinase interaction motif (KIM) within the amino-terminal domain of DUSP5, indicating that the same protein–protein contacts are required for both the inactivation of ERK2 by DUSP5 and for DUSP5 to act as a substrate for this MAPK. Using a combination of pharmacological inhibitors and phospho-site mutants we can find no evidence that phosphorylation of DUSP5 by ERK2 significantly affects either the half-life of the DUSP5 protein or its ability to bind to, inactivate or anchor ERK2 in the nucleus. However, co-expression of ERK2 results in significant stabilisation of DUSP5, which is accompanied by reduced levels of DUSP5 ubiquitination. These changes are independent of ERK2 kinase activity but absolutely depend on the ability of ERK2 to bind to DUSP5. We conclude that DUSP5 is stabilised by complex formation with its physiological substrate and that this may reinforce its activity as both a phosphatase and nuclear anchor for ERK2.
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negative feedback regulation of fgf signalling by DUSP6 mkp 3 is driven by erk1 2 and mediated by ets factor binding to a conserved site within the DUSP6 mkp 3 gene promoter
Biochemical Journal, 2008Co-Authors: Maria Ekerot, Laurent Delavaine, Christopher J. Staples, Marios P Stavridis, Michael Mitchell, David M Owens, Iain D Keenan, Robin J Dickinson, Kate G Storey, Stephen M KeyseAbstract:DUSP6 (dual-specificity phosphatase 6), also known as MKP-3 [MAPK (mitogen-activated protein kinase) phosphatase-3] specifically inactivates ERK1/2 (extracellular-signal-regulated kinase 1/2) in vitro and in vivo. DUSP6/MKP-3 is inducible by FGF (fibroblast growth factor) signalling and acts as a negative regulator of ERK activity in key and discrete signalling centres that direct outgrowth and patterning in early vertebrate embryos. However, the molecular mechanism by which FGFs induce DUSP6/MKP-3 expression and hence help to set ERK1/2 signalling levels is unknown. In the present study, we demonstrate, using pharmacological inhibitors and analysis of the murine DUSP6/MKP-3 gene promoter, that the ERK pathway is critical for FGF-induced DUSP6/MKP-3 transcription. Furthermore, we show that this response is mediated by a conserved binding site for the Ets (E twenty-six) family of transcriptional regulators and that the Ets2 protein, a known target of ERK signalling, binds to the endogenous DUSP6/MKP-3 promoter. Finally, the murine DUSP6/MKP-3 promoter coupled to EGFP (enhanced green fluorescent protein) recapitulates the specific pattern of endogenous DUSP6/MKP-3 mRNA expression in the chicken neural plate, where its activity depends on FGFR (FGF receptor) and MAPK signalling and an intact Ets-binding site. These findings identify a conserved Ets-factor-dependent mechanism by which ERK signalling activates DUSP6/MKP-3 transcription to deliver ERK1/2-specific negative-feedback control of FGF signalling.
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the dual specificity protein phosphatase dusp9 mkp 4 is essential for placental function but is not required for normal embryonic development
Molecular and Cellular Biology, 2005Co-Authors: Graham R Christie, Robin J Dickinson, David J Williams, Fiona Macisaac, Ian Rosewell, Stephen M KeyseAbstract:To elucidate the physiological role(s) of DUSP9 (dual-specificity phosphatase 9), also known as MKP-4 (mitogen-activated protein kinase [MAPK] phosphatase 4), the gene was deleted in mice. Crossing male chimeras with wild-type females resulted in heterozygous (DUSP9+/−) females. However, when these animals were crossed with wild-type (DUSP9+/y) males none of the progeny carried the targeted DUSP9 allele, indicating that both female heterozygous and male null (DUSP9−/y) animals die in utero. The DUSP9 gene is on the X chromosome, and this pattern of embryonic lethality is consistent with the selective inactivation of the paternal X chromosome in the extraembryonic tissues of the mouse, suggesting that DUSP9/MKP4 performs an essential function during placental development. Examination of embryos between 8 and 10.5 days postcoitum confirmed that lethality was due to a failure of labyrinth development, and this correlates exactly with the normal expression pattern of DUSP9/MKP-4 in the trophoblast giant cells and labyrinth of the placenta. Finally, when the placental defect was rescued, male null (DUSP9−/y) embryos developed to term, appeared normal, and were fertile. Our results indicate that DUSP9/MKP-4 is essential for placental organogenesis but is otherwise dispensable for mammalian embryonic development and highlights the critical role of dual-specificity MAPK phosphatases in the regulation of developmental outcomes in vertebrates.
Glenda Eger - One of the best experts on this subject based on the ideXlab platform.
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dual specificity phosphatase dusp 4 is induced by platelet derived growth factor bb in an erk1 2 stat3 and p53 dependent manner
Biochemical and Biophysical Research Communications, 2019Co-Authors: Glenda Eger, Niki Sarri, Charlotte Rorsman, Johan LennartssonAbstract:Abstract Dual specificity phosphatase (DUSP) 4 has been described as a negative regulator of MAP kinase signaling, in particular for the ERK1/2 and JNK pathways. We found that DUSP4 expression was upregulated in response to prolonged platelet-derived growth factor (PDGF)-BB stimulation. The PDGF-BB-induced DUSP4 expression was dependent on ERK1/2, STAT3 and p53. We found that inhibition of ERK1/2 effectively reduced DUSP4 mRNA levels, whereas STAT3 was necessary for maintaining p53 expression. p53 has binding sites in the DUSP4 promoter and was found to promote DUSP4 expression.
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dual specificity phosphatase dusp 4 is induced by platelet derived growth factor bb in an erk1 2 stat3 and p53 dependent manner
Biochemical and Biophysical Research Communications, 2019Co-Authors: Glenda Eger, Niki Sarri, Charlotte Rorsman, Johan Lennartsson, Carlhenrik HeldinAbstract:Abstract Dual specificity phosphatase (DUSP) 4 has been described as a negative regulator of MAP kinase signaling, in particular for the ERK1/2 and JNK pathways. We found that DUSP4 expression was upregulated in response to prolonged platelet-derived growth factor (PDGF)-BB stimulation. The PDGF-BB-induced DUSP4 expression was dependent on ERK1/2, STAT3 and p53. We found that inhibition of ERK1/2 effectively reduced DUSP4 mRNA levels, whereas STAT3 was necessary for maintaining p53 expression. p53 has binding sites in the DUSP4 promoter and was found to promote DUSP4 expression.
Charlotte Rorsman - One of the best experts on this subject based on the ideXlab platform.
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dual specificity phosphatase dusp 4 is induced by platelet derived growth factor bb in an erk1 2 stat3 and p53 dependent manner
Biochemical and Biophysical Research Communications, 2019Co-Authors: Glenda Eger, Niki Sarri, Charlotte Rorsman, Johan LennartssonAbstract:Abstract Dual specificity phosphatase (DUSP) 4 has been described as a negative regulator of MAP kinase signaling, in particular for the ERK1/2 and JNK pathways. We found that DUSP4 expression was upregulated in response to prolonged platelet-derived growth factor (PDGF)-BB stimulation. The PDGF-BB-induced DUSP4 expression was dependent on ERK1/2, STAT3 and p53. We found that inhibition of ERK1/2 effectively reduced DUSP4 mRNA levels, whereas STAT3 was necessary for maintaining p53 expression. p53 has binding sites in the DUSP4 promoter and was found to promote DUSP4 expression.
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dual specificity phosphatase dusp 4 is induced by platelet derived growth factor bb in an erk1 2 stat3 and p53 dependent manner
Biochemical and Biophysical Research Communications, 2019Co-Authors: Glenda Eger, Niki Sarri, Charlotte Rorsman, Johan Lennartsson, Carlhenrik HeldinAbstract:Abstract Dual specificity phosphatase (DUSP) 4 has been described as a negative regulator of MAP kinase signaling, in particular for the ERK1/2 and JNK pathways. We found that DUSP4 expression was upregulated in response to prolonged platelet-derived growth factor (PDGF)-BB stimulation. The PDGF-BB-induced DUSP4 expression was dependent on ERK1/2, STAT3 and p53. We found that inhibition of ERK1/2 effectively reduced DUSP4 mRNA levels, whereas STAT3 was necessary for maintaining p53 expression. p53 has binding sites in the DUSP4 promoter and was found to promote DUSP4 expression.
