PFKFB3 activation in cancer cells by the p38/MK2 pathway in response to stress stimuli

2013 ◽  
Vol 452 (3) ◽  
pp. 531-543 ◽  
Author(s):  
Laura Novellasdemunt ◽  
Laurent Bultot ◽  
Anna Manzano ◽  
Francesc Ventura ◽  
Jose Luis Rosa ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Cancer Cells ◽  
Serum Response Factor ◽  
Gene Promoter ◽  
Mitogen Activated Protein Kinase ◽  
Early Gene ◽  
Mrna Levels ◽  
Kinase Activation ◽  
Mitogen Activated Protein ◽  
Serum Response

PFK-2/FBPase-2 (6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase) catalyses the synthesis and degradation of Fru-2,6-P2 (fructose 2,6-bisphosphate), a key modulator of glycolysis and gluconeogenesis. The PFKFB3 gene is involved in cell proliferation owing to its role in carbohydrate metabolism. In the present study we analysed the mechanism of regulation of PFKFB3 as an immediate early gene controlled by stress stimuli that activates the p38/MK2 [MAPK (mitogen-activated protein kinase)-activated protein kinase 2] pathway. We report that exposure of HeLa and T98G cells to different stress stimuli (NaCl, H2O2, UV radiation and anisomycin) leads to a rapid increase (15–30 min) in PFKFB3 mRNA levels. The use of specific inhibitors in combination with MK2-deficient cells implicate control by the protein kinase MK2. Transient transfection of HeLa cells with deleted gene promoter constructs allowed us to identify an SRE (serum-response element) to which SRF (serum-response factor) binds and thus transactivates PFKFB3 gene transcription. Direct binding of phospho-SRF to the SRE sequence (−918 nt) was confirmed by ChIP (chromatin immunoprecipiation) assays. Moreover, PFKFB3 isoenzyme phosphorylation at Ser461 by MK2 increases PFK-2 activity. Taken together, the results of the present study suggest a multimodal mechanism of stress stimuli affecting PFKFB3 transcriptional regulation and kinase activation by protein phosphorylation, resulting in an increase in Fru-2,6-P2 concentration and stimulation of glycolysis in cancer cells.

scholarly journals The Noncatalytic Amino Terminus of Mitogen-Activated Protein Kinase Phosphatase 1 Directs Nuclear Targeting and Serum Response Element Transcriptional Regulation

2005 ◽  
Vol 25 (11) ◽  
pp. 4792-4803 ◽  
Author(s):  
J. Julie Wu ◽  
Lei Zhang ◽  
Anton M. Bennett
Keyword(s):  
Transcriptional Regulation ◽  
Protein Kinase ◽  
Mitogen Activated Protein Kinase ◽  
Early Gene ◽  
Nuclear Targeting ◽  
Serum Response Element ◽  
Response Element ◽  
Lxxll Motif ◽  
Mitogen Activated Protein ◽  
Serum Response

ABSTRACT The mitogen-activated protein kinase (MAPK) phosphatase 1 (MKP-1) is an immediate-early gene comprised of a dual-specificity phosphatase domain and a noncatalytic NH2 terminus. Here, we show that the NH2 terminus of MKP-1, containing the cdc25 homology domains A (CH2A) and B (CH2B), mediates MKP-1 nuclear targeting and modulates MAPK-mediated gene expression. An LXXLL motif which is known to mediate protein-protein interactions with nuclear-targeted hormone receptors was identified proximal to the CH2A domain of MKP-1. The NH2 terminus alone of MKP-1 containing this LXXLL motif was sufficient to direct nuclear targeting, and mutating this motif to LXXAA resulted in the exclusion of MKP-1 from the nucleus. We found that the LXXLL motif proximal to the CH2A domain was present in other nuclear-localized MKPs but was absent in MKPs that localized to the cytoplasm. These data suggest that this LXXLL motif confers nuclear targeting properties to the MKPs. The NH2 terminus of MKP-1 was also found to inhibit the activation of the serum response element (SRE) by preventing MAPK-mediated phosphorylation of the regulatory serine 383 residue on Elk-1. Moreover, we show that MKP-1 plays a major role in the attenuation of serum-induced SRE activity, since MKP-1 null fibroblasts exhibited enhanced SRE activity in response to serum compared with wild-type fibroblasts. The NH2 terminus of MKP-1, when reconstituted into MKP-1 null fibroblasts to levels similar to endogenous MKP-1 following serum stimulation, reduced serum-mediated SRE activity. Collectively, these data reveal novel roles for the NH2 terminus of MKP-1 in nuclear targeting and transcriptional regulation.

The proximal serum response element in the Egr-1 promoter mediates response to thrombin in primary human endothelial cells

Blood ◽  
2002 ◽  
Vol 100 (13) ◽  
pp. 4454-4461 ◽  
Author(s):  
Sheng-Qian Wu ◽  
Takashi Minami ◽  
Diana J. Donovan ◽  
William C. Aird
Keyword(s):  
Endothelial Cells ◽  
Protein Kinase ◽  
Serum Response Factor ◽  
Core Promoter ◽  
Mitogen Activated Protein Kinase ◽  
Human Endothelial Cells ◽  
Mobility Shift ◽  
Nuclear Extracts ◽  
Mitogen Activated Protein ◽  
Serum Response

Thrombin signaling in endothelial cells provides an important link between coagulation and inflammation. We report here that thrombin induces endogenous Egr-1 mRNA and Egr-1 promoter activity in primary human endothelial cells by approximately 6-fold and 3-fold, respectively. In transient transfection assays, deletion of the 3′ cluster of serum response elements (SREs), but not the 5′ cluster of SREs, resulted in a loss of thrombin response. When coupled to a heterologous core promoter, a region spanning the 3′ SRE cluster contained information for thrombin response, whereas a region spanning the 5′ SRE cluster had no such effect. A point mutation of the most proximal SRE (SRE-1), but not of the proximal Ets motif or upstream SREs, abrogated the response to thrombin. In electrophoretic mobility shift assays, nuclear extracts from thrombin-treated cells displayed increased binding of total and phosphorylated serum response factor (SRF) to SRE-1. Thrombin-mediated induction of Egr-1 was blocked by inhibitors of MEK1/2, but not by inhibitors of protein kinase C, phosphatidylinositol 3-kinase, or p38 mitogen-activated protein kinase (MAPK). Taken together, these data suggest that thrombin induces Egr-1 expression in endothelial cells by a MAPK-dependent mechanism that involves an interaction between SRF and SRE-1.

scholarly journals Yeast RLM1 encodes a serum response factor-like protein that may function downstream of the Mpk1 (Slt2) mitogen-activated protein kinase pathway.

1995 ◽  
Vol 15 (10) ◽  
pp. 5740-5749 ◽  
Author(s):  
Y Watanabe ◽  
K Irie ◽  
K Matsumoto
Keyword(s):  
Protein Kinase ◽  
Serum Response Factor ◽  
Inhibitory Effect ◽  
Mitogen Activated Protein Kinase ◽  
Growth Inhibitory Effect ◽  
Growth Inhibitory ◽  
Mitogen Activated Protein ◽  
Chromosomal Mutations ◽  
Serum Response ◽  
Kinase Pathway

The MPK1 (SLT2) gene of Saccharomyces cerevisiae encodes a mitogen-activated protein kinase that is regulated by a kinase cascade whose known elements are Pkc1 (a homolog of protein kinase C), Bck1 (Slk1) (a homolog of MEK kinase), and the functionally redundant Mpk1 activators Mkk1 and Mkk2 (homologs of MEK). An activated mutation of MKK1, MKK1P386, inhibits growth when overexpressed. This growth-inhibitory effect was suppressed by the mpk1 delta mutation, suggesting that hyperactivation of the Mpk1 pathway is toxic to cells. To search for genes that interact with the Mpk1 pathway, we isolated both chromosomal mutations and dosage suppressor genes that ameliorate the growth-inhibitory effect of overexpressed Mkk1P386. One of the genes identified by the analysis of chromosomal mutations is RLM1 (resistance to lethality of MKK1P386 overexpression), which encodes a protein homologous to a conserved domain of the MADS (Mcm1, Agamous, Deficiens, and serum response factor) box family of transcription factors. Although rlm1 delta cells grow normally at any temperature, they display a caffeine-sensitive phenotype similar to that observed in mutants defective in BCK1, MKK1/MKK2, or MPK1. A gene fusion that provides Rlm1 with a transcriptional activation domain of Gal4 suppresses bck1 delta and mpk1 delta. A screening for dosage suppressors yielded the MSG5 genes, which encode a dual-specificity protein phosphatase. Our results suggest that Rlm1 functions as a transcription factor downstream of Mpk1 that is subject to activation by the Mpk1 mitogen-activated protein kinase pathway.

scholarly journals MSKs are required for the transcription of the nuclear orphan receptors Nur77, Nurr1 and Nor1 downstream of MAPK signalling

2005 ◽  
Vol 390 (3) ◽  
pp. 749-759 ◽  
Author(s):  
Joanne Darragh ◽  
Ana Soloaga ◽  
Victoria A. Beardmore ◽  
Andrew D. Wingate ◽  
Giselle R. Wiggin ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Camp Response Element Binding ◽  
Mitogen Activated Protein Kinase ◽  
Early Gene ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Activator Protein 1 ◽  
Double Knockout ◽  
Mitogen Activated Protein

MSK (mitogen- and stress-activated protein kinase) 1 and MSK2 are kinases activated downstream of either the ERK (extracellular-signal-regulated kinase) 1/2 or p38 MAPK (mitogen-activated protein kinase) pathways in vivo and are required for the phosphorylation of CREB (cAMP response element-binding protein) and histone H3. Here we show that the MSKs are involved in regulating the transcription of the immediate early gene Nur77. Stimulation of mouse embryonic fibroblasts with PMA, EGF (epidermal growth factor), TNF (tumour necrosis factor) or anisomycin resulted in induction of the Nur77 mRNA. The induction of Nur77 by TNF and anisomycin was abolished in MSK1/2 double-knockout cells, whereas induction was significantly reduced in response to PMA or EGF. The MSK responsive elements were mapped to two AP (activator protein)-1-like elements in the Nur77 promoter. The induction of Nur77 was also blocked by A-CREB, suggesting that MSKs control Nur77 transcription by phosphorylating CREB bound to the two AP-1-like elements. Consistent with the decrease in Nur77 mRNA levels in the MSK1/2-knockout cells, it was also found that MSKs were required for the induction of Nur77 protein by PMA and TNF. MSKs were also found to be required for the transcription of two genes related to Nur77, Nurr1 and Nor1, which were also transcribed in a CREB- or ATF1 (activating transcription factor-1)-dependent manner. Downstream of anisomycin signalling, a second ERK-dependent pathway, independent of MSK and CREB, was also required for the transcription of Nurr1 and Nor1.

Sign in / Sign up

Export Citation Format

Share Document