scholarly journals P62dok, a Negative Regulator of Ras and Mitogen-Activated Protein Kinase (Mapk) Activity, Opposes Leukemogenesis by P210bcr-abl

2001 ◽  
Vol 194 (3) ◽  
pp. 275-284 ◽  
Author(s):  
Antonio Di Cristofano ◽  
Masaru Niki ◽  
Mingming Zhao ◽  
Fredrick G. Karnell ◽  
Bayard Clarkson ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Growth Factor ◽  
Protein Kinase ◽  
Tyrosine Kinases ◽  
Bone Marrow Cells ◽  
Mapk Signaling ◽  
Negative Regulator ◽  
Myelogenous Leukemia ◽  
Mitogen Activated Protein Kinase ◽  
Mitogen Activated Protein

p62dok has been identified as a substrate of many oncogenic tyrosine kinases such as the chronic myelogenous leukemia (CML) chimeric p210bcr-abl oncoprotein. It is also phosphorylated upon activation of many receptors and cytoplamic tyrosine kinases. However, the biological functions of p62dok in normal cell signaling as well as in p210bcr-abl leukemogenesis are as yet not fully understood. Here we show, in hemopoietic and nonhemopoietic cells derived from p62dok−/− mice, that the loss of p62dok results in increased cell proliferation upon growth factor treatment. Moreover, Ras and mitogen-activated protein kinase (MAPK) activation is markedly sustained in p62dok−/− cells after the removal of growth factor. However, p62dok inactivation does not affect DNA damage and growth factor deprivation–induced apoptosis. Furthermore, p62dok inactivation causes a significant shortening in the latency of the fatal myeloproliferative disease induced by retroviral-mediated transduction of p210bcr-abl in bone marrow cells. These data indicate that p62dok acts as a negative regulator of growth factor–induced cell proliferation, at least in part through downregulating Ras/MAPK signaling pathway, and that p62dok can oppose leukemogenesis by p210bcr-abl.

scholarly journals MKP-3 Has Essential Roles as a Negative Regulator of the Ras/Mitogen-Activated Protein Kinase Pathway during Drosophila Development

2004 ◽  
Vol 24 (2) ◽  
pp. 573-583 ◽  
Author(s):  
Myungjin Kim ◽  
Guang-Ho Cha ◽  
Sunhong Kim ◽  
Jun Hee Lee ◽  
Jeehye Park ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Cell Fate ◽  
Photoreceptor Cells ◽  
Mapk Signaling ◽  
Negative Regulator ◽  
Mitogen Activated Protein Kinase ◽  
Loss Of Function ◽  
Wing Vein ◽  
Mitogen Activated Protein

ABSTRACT Mitogen-activated protein kinase (MAPK) phosphatase 3 (MKP-3) is a well-known negative regulator in the Ras/extracellular signal-regulated kinase (ERK)-MAPK signaling pathway responsible for cell fate determination and proliferation during development. However, the physiological roles of MKP-3 and the mechanism by which MKP-3 regulates Ras/Drosophila ERK (DERK) signaling in vivo have not been determined. Here, we demonstrated that Drosophila MKP-3 (DMKP-3) is critically involved in cell differentiation, proliferation, and gene expression by suppressing the Ras/DERK pathway, specifically binding to DERK via the N-terminal ERK-binding domain of DMKP-3. Overexpression of DMKP-3 reduced the number of photoreceptor cells and inhibited wing vein differentiation. Conversely, DMKP-3 hypomorphic mutants exhibited extra photoreceptor cells and wing veins, and its null mutants showed striking phenotypes, such as embryonic lethality and severe defects in oogenesis. All of these phenotypes were highly similar to those of the gain-of-function mutants of DERK/rl. The functional interaction between DMKP-3 and the Ras/DERK pathway was further confirmed by genetic interactions between DMKP-3 loss-of-function mutants or overexpressing transgenic flies and various mutants of the Ras/DERK pathway. Collectively, these data provide the direct evidences that DMKP-3 is indispensable to the regulation of DERK signaling activity during Drosophila development.

scholarly journals Linc02381 Exacerbates Rheumatoid Arthritis Through Adsorbing miR-590-5p and Activating the Mitogen-Activated Protein Kinase Signaling Pathway in Rheumatoid arthritis-fibroblast-like synoviocytes

2020 ◽  
Vol 29 ◽  
pp. 096368972093802
Author(s):  
Jing Wang ◽  
Qing Zhao
Keyword(s):  
Rheumatoid Arthritis ◽  
Cell Proliferation ◽  
Protein Kinase ◽  
Signaling Pathway ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Mitogen Activated Protein ◽  
Synovial Tissues ◽  
Proliferation And Invasion ◽  
Fibroblast Like Synoviocytes

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. New evidence suggested that linc02381 suppressed colorectal cancer progression by regulating PI3 K signaling pathway, but the role of linc02381 in other diseases, such as RA, remains unclear. This study aimed to reveal the mechanism of linc02381 in RA progression. In vivo and in vitro, we found that linc02381 was upregulated in RA synovial tissues or RA fibroblast-like synoviocytes (RA-FLSs, P < 0.01), which were detected by quantitative real-time polymerase chain reaction. Cell Counting Kit-8, EDU, and Transwell assays revealed that linc02381 overexpression enhanced cell proliferation and invasion, and linc02381 knockdown inhibited cell proliferation and invasion in FLSs. Moreover, the results of bioinformatics analysis, luciferase reporter gene assay, and pull-down assay verified that linc02381 could directly bind with miR-590-5p. MiR-590-5p was downregulated in RA-FLSs, and overexpression of linc02381 suppressed expression of miR-590-5p that post-transcriptionally suppressed the expression of mitogen-activated protein kinase kinase 3 (MAP2K3), and overexpression of miR-590-5p reversed the effect of linc02381 overexpression on MAP2K3 expression. MiR-590-5p inhibitor reversed the inhibition effect of linc02381 knockdown on proliferation and invasion of FLSs, which enhanced expression of MAP2K3, and activation of p38 and AP-1 in the MAPK signaling pathway. In summary, linc02381 was upregulated in RA synovial tissues and RA-FLSs, and it exacerbated RA by adsorbing miR-590-5p to activate the MAPK signaling pathway.

scholarly journals Metalloproteinases and Transforming Growth Factor-α Mediate Substance P-induced Mitogen-activated Protein Kinase Activation and Proliferation in Human Colonocytes

2004 ◽  
Vol 279 (44) ◽  
pp. 45519-45527 ◽  
Author(s):  
Hon-Wai Koon ◽  
Dezheng Zhao ◽  
Xi Na ◽  
Mary P. Moyer ◽  
Charalabos Pothoulakis
Keyword(s):  
Cell Proliferation ◽  
Growth Factor ◽  
Protein Kinase ◽  
Transforming Growth Factor ◽  
Mitogen Activated Protein Kinase ◽  
Chronic Colitis ◽  
Transforming Growth Factor Α ◽  
Egfr Ligands ◽  
Mitogen Activated Protein ◽  
Factor Α

Substance P (SP) participates in acute intestinal inflammation via binding to the G-protein-coupled neurokinin-1 receptor (NK-1R) and release of proinflammatory cytokines from colonic epithelial cells. SP also stimulates cell proliferation, a critical event in tissue healing during chronic colitis, via transactivation of the epidermal growth factor (EGF) receptor (EGFR) and activation of mitogen-activated protein kinase (MAPK). Here we examined the mechanism by which SP induces EGFR and MAPK activation. We used non-transformed human NCM460 colonocytes stably transfected with the human NK-1R (NCM460-NK-1R cells) as well as untransfected U373 MG cells expressing high levels of endogenous NK-1R. Exposure of both cell lines to SP (10–7m) stimulated EGFR activation (1 min) followed by extracellular signal-regulated protein kinase (ERK1/2) activation (2–5 min). SP-induced ERK1/2 activation was blocked by pretreatment with the metalloproteinase inhibitor Batimastat/GM6001, the EGFR phosphorylation inhibitor AG1478, and the tumor necrosis factor-α-converting enzyme (TACE) inhibitor TAPI-1. Pretreatment with antibodies against potential EGFR ligands suggested that transforming growth factor-α (TGFα), but not the other EGFR ligands EGF, heparin-binding EGF, or amphiregulin, mediates SP-induced EGFR transactivation. SP stimulated TGFα release into the extracellular space that was measurable within 2 min, and this release was inhibited by metalloproteinase inhibitors and the TACE inhibitor TAPI-1. SP also induced MAPK-mediated cell proliferation that was inhibited by TACE, matrix metalloproteinase (MMP), EGFR, and MEK1 inhibitors. Thus, in human colonocytes, NK-1R-induced EGFR and MAPK activation and cell proliferation involve matrix metalloproteinases (most likely TACE) and the release of TGFα. These signaling mechanisms may be involved in the protective effects of NK-1R in chronic colitis.

scholarly journals Late Endosomal Traffic of the Epidermal Growth Factor Receptor Ensures Spatial and Temporal Fidelity of Mitogen-activated Protein Kinase Signaling

2007 ◽  
Vol 18 (12) ◽  
pp. 4698-4710 ◽  
Author(s):  
N. Taub ◽  
D. Teis ◽  
H. L. Ebner ◽  
M. W. Hess ◽  
L. A. Huber
Keyword(s):  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Protein Kinase ◽  
Growth Factor Receptor ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Late Endosomes ◽  
Mitogen Activated Protein ◽  
Epidermal Growth ◽  
Nuclear Targets

Mitogen-activated protein kinase (MAPK) signaling is regulated by assembling distinct scaffold complexes at the plasma membrane and on endosomes. Thus, spatial resolution might be critical to determine signaling specificity. Therefore, we investigated whether epidermal growth factor receptor (EGFR) traffic through the endosomal system provides spatial information for MAPK signaling. To mislocalize late endosomes to the cell periphery we used the dynein subunit p50 dynamitin. The peripheral translocation of late endosomes resulted in a prolonged EGFR activation on late endosomes and a slow down in EGFR degradation. Continuous EGFR signaling from late endosomes caused sustained extracellular signal-regulated kinase and p38 signaling and resulted in hyperactivation of nuclear targets, such as Elk-1. In contrast, clustering late endosomes in the perinuclear region by expression of dominant active Rab7 delayed the entry of the EGFR into late endosomes, which caused a delay in EGFR degradation and a sustained MAPK signaling. Surprisingly, the activation of nuclear targets was reduced. Thus, we conclude that appropriate trafficking of the activated EGFR through endosomes controls the spatial and temporal regulation of MAPK signaling.

scholarly journals The Stress Kinase Mitogen-Activated Protein Kinase Kinase (Mkk)7 Is a Negative Regulator of Antigen Receptor and Growth Factor Receptor–Induced Proliferation in Hematopoietic Cells

2001 ◽  
Vol 194 (6) ◽  
pp. 757-768 ◽  
Author(s):  
Takehiko Sasaki ◽  
Teiji Wada ◽  
Hiroyuki Kishimoto ◽  
Junko Irie-Sasaki ◽  
Goichi Matsumoto ◽  
...  
Keyword(s):  
B Cells ◽  
Growth Factor ◽  
Mast Cells ◽  
Protein Kinase ◽  
Hematopoietic Cells ◽  
Antigen Receptor ◽  
Negative Regulator ◽  
Mitogen Activated Protein Kinase ◽  
Mitogen Activated Protein ◽  
Jnk Activation

The dual specificity kinases mitogen-activated protein kinase (MAPK) kinase (MKK)7 and MKK4 are the only molecules known to directly activate the stress kinases stress-activated protein kinases (SAPKs)/c-Jun N-terminal kinases (JNKs) in response to environmental or mitogenic stimuli. To examine the physiological role of MKK7 in hematopoietic cells, we used a gene targeting strategy to mutate MKK7 in murine T and B cells and non-lymphoid mast cells. Loss of MKK7 in thymocytes and mature B cells results in hyperproliferation in response to growth factor and antigen receptor stimulation and increased thymic cellularity. Mutation of mkk7 in mast cells resulted in hyperproliferation in response to the cytokines interleukin (IL)-3 and stem cell factor (SCF). SAPK/JNK activation was completely abolished in the absence of MKK7, even though expression of MKK4 was strongly upregulated in mkk7−/− mast cell lines, and phosphorylation of MKK4 occurred normally in response to multiple stress stimuli. Loss of MKK7 did not affect activation of extracellular signal–regulated kinase (ERK)1/2 or p38 MAPK. mkk7−/− mast cells display reduced expression of JunB and the cell cycle inhibitor p16INK4a and upregulation of cyclinD1. Reexpression of p16INK4a in mkk7−/− mast cells abrogates the hyperproliferative response. Apoptotic responses to a variety of stimuli were not affected. Thus, MKK7 is an essential and specific regulator of stress-induced SAPK/JNK activation in mast cells and MKK7 negatively regulates growth factor and antigen receptor–driven proliferation in hematopoietic cells. These results indicate that the MKK7-regulated stress signaling pathway can function as negative regulator of cell growth in multiple hematopoietic lineages.

scholarly journals Phosphoinositide 3-Kinase–Dependent Membrane Recruitment of P62dok Is Essential for Its Negative Effect on Mitogen-Activated Protein (Map) Kinase Activation

2001 ◽  
Vol 194 (3) ◽  
pp. 265-274 ◽  
Author(s):  
Mingming Zhao ◽  
Arndt A.P. Schmitz ◽  
Yi Qin ◽  
Antonio Di Cristofano ◽  
Pier Paolo Pandolfi ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Plasma Membrane ◽  
Growth Factor ◽  
Mapk Pathway ◽  
Mapk Signaling ◽  
Negative Regulator ◽  
Membrane Recruitment ◽  
Mitogen Activated Protein ◽  
Negative Effect ◽  
Phosphoinositide 3 Kinase

A major pathway by which growth factors, such as platelet-derived growth factor (PDGF), regulate cell proliferation is via the receptor tyrosine kinase/Ras/mitogen-activated protein kinase (MAPK) signaling cascade. The output of this pathway is subjected to tight regulation of both positive and negative regulators. One such regulator is p62dok, the prototype of a newly identified family of adaptor proteins. We recently provided evidence, through the use of p62dok-deficient cells, that p62dok acts as a negative regulator of growth factor–induced cell proliferation and the Ras/MAPK pathway. We show here that reintroduction of p62dok into p62dok−/− cells can suppress the increased cell proliferation and prolonged MAPK activity seen in these cells, and that plasma membrane recruitment of p62dok is essential for its function. We also show that the PDGF-triggered plasma membrane translocation of p62dok requires activation of phosphoinositide 3-kinase (PI3-kinase) and binding of its pleckstrin homology (PH) domain to 3′-phosphorylated phosphoinositides. Furthermore, we demonstrate that p62dok can exert its negative effect on the PDGFR/MAPK pathway independently of its ability to associate with RasGAP and Nck. We conclude that p62dok functions as a negative regulator of the PDGFR/Ras/MAPK signaling pathway through a mechanism involving PI3-kinase–dependent recruitment of p62dok to the plasma membrane.

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