scholarly journals Protein kinase function and glutathionylation

2004 ◽  
Vol 381 (3) ◽  
Author(s):  
Anthony N. ANSELMO ◽  
Melanie H. COBB
Keyword(s):  
Protein Kinase ◽  
Redox Balance ◽  
Cellular Protein ◽  
Mitogen Activated Protein Kinase ◽  
General Mechanism ◽  
Post Translational Modification ◽  
Oxidative Stresses ◽  
Mitogen Activated Protein ◽  
Thiol Redox ◽  
And Function

Intracellular reactive oxygen species are generated as a by-product of normal metabolic processes and can both damage cellular constituents and function as important signalling species. This signalling often involves changes in the thiol redox balance. As an antioxidant, glutathione serves in maintaining the reduced state of cellular protein thiol groups. The paper by Cross and Templeton appearing in this issue of the Biochemical Journal describes a mechanism by which glutathionylation plays a key role in the regulation of the kinase activity of MEKK1 [MAP (mitogen-activated protein kinase)/ERK (extracellular-signal-regulated kinase) kinase kinase; MAP3K] in response to oxidative stresses. This type of post-translational-modification glutathionylation may represent a general mechanism by which protein kinase function can be regulated.

scholarly journals The Roles of Mitogen-Activated Protein Kinase Pathways in TGF-β-Induced Epithelial-Mesenchymal Transition

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Ting Gui ◽  
Yujing Sun ◽  
Aiko Shimokado ◽  
Yasuteru Muragaki
Keyword(s):  
Growth Factors ◽  
Protein Kinase ◽  
Epithelial Mesenchymal Transition ◽  
Mapk Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Important Process ◽  
Mesenchymal Transition ◽  
Mitogen Activated Protein ◽  
And Function ◽  
External Signals

The mitogen-activated protein kinase (MAPK) pathway allows cells to interpret external signals and respond appropriately, especially during the epithelial-mesenchymal transition (EMT). EMT is an important process during embryonic development, fibrosis, and tumor progression in which epithelial cells acquire mesenchymal, fibroblast-like properties and show reduced intercellular adhesion and increased motility. TGF-β signaling is the first pathway to be described as an inducer of EMT, and its relationship with the Smad family is already well characterized. Studies of four members of the MAPK family in different biological systems have shown that the MAPK and TGF-β signaling pathways interact with each other and have a synergistic effect on the secretion of additional growth factors and cytokines that in turn promote EMT. In this paper, we present background on the regulation and function of MAPKs and their cascades, highlight the mechanisms of MAPK crosstalk with TGF-β signaling, and discuss the roles of MAPKs in EMT.

scholarly journals G Protein-Coupled Receptor-Mediated Mitogen-Activated Protein Kinase Activation through Cooperation of Gαq and Gαi Signals

2000 ◽  
Vol 20 (18) ◽  
pp. 6837-6848 ◽  
Author(s):  
Andree Blaukat ◽  
Ana Barac ◽  
Michael J. Cross ◽  
Stefan Offermanns ◽  
Ivan Dikic
Keyword(s):  
Protein Kinase ◽  
G Protein ◽  
Tyrosine Kinases ◽  
Synergistic Effects ◽  
Mitogen Activated Protein Kinase ◽  
General Mechanism ◽  
Mitogen Activated Protein ◽  
Novel Concept ◽  
G Protein Coupled ◽  
Stimulation Of

ABSTRACT G protein-coupled receptors (GPCRs) have been shown to stimulate extracellular regulated kinases (ERKs) through a number of linear pathways that are initiated by Gq/11 or Giproteins. We studied signaling to the ERK cascade by receptors that simultaneously activate both G protein subfamilies. In HEK293T cells, bradykinin B2 receptor (B2R)-induced stimulation of ERK2 and transcriptional activity of Elk1 are dependent on Gαq-mediated protein kinase C (PKC) and on Gαi-induced Ras activation, while they are independent of Gβγ subunits, phosphatidylinositol 3-kinase, and tyrosine kinases. Similar results were obtained with m1 and m3muscarinic receptors in HEK293T cells and with the B2R in human and mouse fibroblasts, indicating a general mechanism in signaling toward the ERK cascade. Furthermore, the bradykinin-induced activation of ERK is strongly reduced in Gαq/11-deficient fibroblasts. In addition, we found that constitutively active mutants of Gαq/11 or Gαi proteins alone poorly stimulate ERK2, whereas a combination of both led to synergistic effects. We conclude that dually coupled GPCRs require a cooperation of Gαi- and Gq/11-mediated pathways for efficient stimulation of the ERK cascade. Cooperative signaling by multiple G proteins thus might represent a novel concept implicated in the regulation of cellular responses by GPCRs.

scholarly journals TRIM25 promotes Capicua degradation independently of ERK in the absence of ATXN1L

BMC Biology ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Derek Wong ◽  
Lisa Sogerer ◽  
Samantha S. Lee ◽  
Victor Wong ◽  
Amy Lum ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Prognostic Factor ◽  
Cell Lines ◽  
Target Genes ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Mitogen Activated Protein ◽  
Cancer Types ◽  
And Function ◽  
Erk Activity

Abstract Background Aberrations in Capicua (CIC) have recently been implicated as a negative prognostic factor in a multitude of cancer types through the derepression of targets downstream of the mitogen-activated protein kinase (MAPK) signaling cascade, such as oncogenic E26 transformation-specific (ETS) transcription factors. The Ataxin-family protein ATXN1L has previously been reported to interact with CIC in both developmental and disease contexts to facilitate the repression of CIC target genes and promote the post-translational stability of CIC. However, little is known about the mechanisms at the base of ATXN1L-mediated CIC post-translational stability. Results Functional in vitro studies utilizing ATXN1LKO human cell lines revealed that loss of ATXN1L leads to the accumulation of polyubiquitinated CIC protein, promoting its degradation through the proteasome. Although transcriptomic signatures of ATXN1LKO cell lines indicated upregulation of the mitogen-activated protein kinase pathway, ERK activity was found to contribute to CIC function but not stability. Degradation of CIC protein following loss of ATXN1L was instead observed to be mediated by the E3 ubiquitin ligase TRIM25 which was further validated using glioma-derived cell lines and the TCGA breast carcinoma and liver hepatocellular carcinoma cohorts. Conclusions The post-translational regulation of CIC through ATXN1L and TRIM25 independent of ERK activity suggests that the regulation of CIC stability and function is more intricate than previously appreciated and involves several independent pathways. As CIC status has become a prognostic factor in several cancer types, further knowledge into the mechanisms which govern CIC stability and function may prove useful for future therapeutic approaches.

The localization and function of p38α mitogen-activated protein kinase in rat oocytes

2018 ◽  
Vol 53 (3) ◽  
pp. 636-643
Author(s):  
S Hu ◽  
Q Yu ◽  
Y Wang ◽  
D Ke ◽  
F Zhou ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Mitogen Activated Protein Kinase ◽  
Mitogen Activated Protein ◽  
And Function

scholarly journals Regulation of tetradecanoyl phorbol acetate-induced responses in NIH 3T3 cells by GAP, the GTPase-activating protein associated with p21c-ras.

1992 ◽  
Vol 12 (3) ◽  
pp. 936-945 ◽  
Author(s):  
M Nori ◽  
G L'Allemain ◽  
M J Weber
Keyword(s):  
Signal Transduction ◽  
Protein Kinase ◽  
Signal Transduction Pathway ◽  
Cellular Protein ◽  
Mitogen Activated Protein Kinase ◽  
Gtpase Activating Protein ◽  
Tetradecanoyl Phorbol Acetate ◽  
Mitogen Activated Protein ◽  
Ras Family ◽  
Dependent Signal

Proteins of the ras family of oncogenes have been implicated in signal transduction pathways initiated by protein kinase C (PKC) and by tyrosine kinase oncogenes and receptors, but the role that ras plays in these diverse signalling systems is poorly defined. The activity of ras proteins has been shown to be controlled in part by a cellular protein, GAP (GTPase-activating protein), that negatively regulates p21c-ras by enhancing its intrinsic GTPase activity. Thus, overexpression of GAP provides a tool for determining the step(s) in signal transduction dependent on p21c-ras activity. In this paper, we report that overexpression of GAP blocks the phorbol ester (tetradecanoyl phorbol acetate [TPA])-induced activation of p42 mitogen-activated protein kinase (p42mapk), c-fos expression, and DNA synthesis. GAP overexpression did not block responses to serum or fluoroaluminate. Moreover, not all biochemical events elicited by TPA were affected by GAP overexpression, as increased glucose uptake and phosphorylation of MARCKS, a major PKC substrate, occurred normally. Reduction of GAP expression to near normal levels restored the ability of the cells to activate p42mapk in response to TPA. These findings suggest that ras and GAP together play a key role in a PKC-dependent signal transduction pathway which leads to p42mapk activation and cell proliferation.

Dual-specificity phosphatases: critical regulators with diverse cellular targets

2009 ◽  
Vol 418 (3) ◽  
pp. 475-489 ◽  
Author(s):  
Kate I. Patterson ◽  
Tilman Brummer ◽  
Philippa M. O'brien ◽  
Roger J. Daly
Keyword(s):  
Protein Kinase ◽  
Sequence Similarity ◽  
Mitogen Activated Protein Kinase ◽  
Cellular Targets ◽  
Dual Specificity ◽  
Extracellular Signal ◽  
Mitogen Activated Protein ◽  
Dual Specificity Phosphatases ◽  
The One ◽  
And Function

DUSPs (dual-specificity phosphatases) are a heterogeneous group of protein phosphatases that can dephosphorylate both phosphotyrosine and phosphoserine/phosphothreonine residues within the one substrate. DUSPs have been implicated as major modulators of critical signalling pathways that are dysregulated in various diseases. DUSPs can be divided into six subgroups on the basis of sequence similarity that include slingshots, PRLs (phosphatases of regenerating liver), Cdc14 phosphatases (Cdc is cell division cycle), PTENs (phosphatase and tensin homologues deleted on chromosome 10), myotubularins, MKPs (mitogen-activated protein kinase phosphatases) and atypical DUSPs. Of these subgroups, a great deal of research has focused on the characterization of the MKPs. As their name suggests, MKPs dephosphorylate MAPK (mitogen-activated protein kinase) proteins ERK (extracellular-signal-regulated kinase), JNK (c-Jun N-terminal kinase) and p38 with specificity distinct from that of individual MKP proteins. Atypical DUSPs are mostly of low-molecular-mass and lack the N-terminal CH2 (Cdc25 homology 2) domain common to MKPs. The discovery of most atypical DUSPs has occurred in the last 6 years, which has initiated a large amount of interest in their role and regulation. In the past, atypical DUSPs have generally been grouped together with the MKPs and characterized for their role in MAPK signalling cascades. Indeed, some have been shown to dephosphorylate MAPKs. The current literature hints at the potential of the atypical DUSPs as important signalling regulators, but is crowded with conflicting reports. The present review provides an overview of the DUSP family before focusing on atypical DUSPs, emerging as a group of proteins with vastly diverse substrate specificity and function.

Structure and function of MK5/PRAK: the loner among the mitogen-activated protein kinase-activated protein kinases

2013 ◽  
Vol 394 (9) ◽  
pp. 1115-1132 ◽  
Author(s):  
Ugo Moens ◽  
Sergiy Kostenko
Keyword(s):  
Protein Kinase ◽  
Protein Kinases ◽  
Kinase Domain ◽  
Mitogen Activated Protein Kinase ◽  
Cellular Processes ◽  
Mapk Pathways ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
Apoptosis Gene ◽  
And Function

Abstract Mitogen-activated protein kinase (MAPK) pathways are important signal transduction pathways that control pivotal cellular processes including proliferation, differentiation, survival, apoptosis, gene regulation, and motility. MAPK pathways consist of a relay of consecutive phosphorylation events exerted by MAPK kinase kinases, MAPK kinases, and MAPKs. Conventional MAPKs are characterized by a conserved Thr-X-Tyr motif in the activation loop of the kinase domain, while atypical MAPKs lack this motif and do not seem to be organized into the classical three-tiered kinase cascade. One functional group of conventional and atypical MAPK substrates consists of protein kinases known as MAPK-activated protein kinases. Eleven mammalian MAPK-activated protein kinases have been identified, and they are divided into five subgroups: the ribosomal-S6-kinases RSK1-4, the MAPK-interacting kinases MNK1 and 2, the mitogen- and stress-activated kinases MSK1 and 2, the MAPK-activated protein kinases MK2 and 3, and the MAPK-activated protein kinase MK5 (also referred to as PRAK). MK5/PRAK is the only MAPK-activated protein kinase that is a substrate for both conventional and atypical MAPK, while all other MAPKAPKs are exclusively phosphorylated by conventional MAPKs. This review focuses on the structure, activation, substrates, functions, and possible implications of MK5/PRAK in malignant and nonmalignant diseases.

scholarly journals Destabilization of Raf-1 by geldanamycin leads to disruption of the Raf-1-MEK-mitogen-activated protein kinase signalling pathway.

1996 ◽  
Vol 16 (10) ◽  
pp. 5839-5845 ◽  
Author(s):  
T W Schulte ◽  
M V Blagosklonny ◽  
L Romanova ◽  
J F Mushinski ◽  
B P Monia ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Phorbol Esters ◽  
Signalling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Signalling Pathway ◽  
Mapk Signalling ◽  
Mitogen Activated Protein ◽  
And Function ◽  
Nih 3T3 ◽  
Benzoquinone Ansamycin

The serine/threonine kinase Raf-1 functions downstream of Rats in a signal transduction cascade which transmits mitogenic stimuli from the plasma membrane to the nucleus. Raf-1 integrates signals coming from extracellular factors and, in turn, activates its substrate, MEK kinase. MEK activates mitogen-activated protein kinase (MAPK), which phosphorylates other kinases as well as transcription factors. Raf-1 exists in a complex with HSP90 and other proteins. The benzoquinone ansamycin geldanamycin (GA) binds to HSP90 and disrupts the Raf-1-HSP90 multimolecular complex, leading to destabilization of Raf-1. In this study, we examined whether Raf-1 destabilization is sufficient to block the Raf-1-MEK-MAPK signalling pathway and whether GA specifically inactivates the Raf-1 component of this pathway. Using the model system of NIH 3T3 cells stimulated with phorbol 12-myristate 13-acetate (PMA), we show that GA does not affect the ability of protein kinase C alpha to be activated by phorbol esters, but it does block activation of MEK and MAPK. Further, GA does not decrease the activity of constitutively active MEK in transiently transfected cells. Finally, disruption of the Raf-1-MEK-MAPK signalling pathway by GA prevents both the PMA-induced proliferative response and PMA-induced activation of a MAPK-sensitive nuclear transcription factor. Thus, we demonstrate that interaction between HSP90 and Raf-1 is a sine qua non for Raf stability and function as a signal transducer and that the effects observed cannot be attributed to a general impairment of protein kinase function.

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