Induction of FucT-VII by the Ras/MAP kinase cascade in Jurkat T cells

Blood ◽  
2003 ◽  
Vol 102 (5) ◽  
pp. 1771-1778 ◽  
Author(s):  
Sheila M. Barry ◽  
Dimitrios G. Zisoulis ◽  
Joel W. Neal ◽  
Neil A. Clipstone ◽  
Geoffrey S. Kansas
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Map Kinase ◽  
Ras Signaling ◽  
Major Pathway ◽  
Map Kinase Cascade ◽  
Extracellular Signal ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
Selectin Ligand

AbstractInduction of the α1,3-fucosyltransferase FucT-VII in T lymphocytes is crucial for selectin ligand formation, but the signaling and transcriptional pathways that govern FucT-VII expression are unknown. Here, using a novel, highly phorbol myristate acetate (PMA)–responsive variant of the Jurkat T-cell line, we identify Ras and downstream mitogen-activated protein (MAP) kinase pathways as essential mediators of FucT-VII gene expression. PMA induced FucT-VII in only a subset of treated cells, similar to expression of FucT-VII in normal activated CD4 T cells. Introduction of constitutively active Ras or Raf by recombinant retroviruses induced FucT-VII expression only in that subset of cells expressing the highest levels of Ras, suggesting that induction of FucT-VII required a critical threshhold of Ras signaling. Both PMA treatment and introduction of active Ras led to rolling on E-selectin. Pharmacologic inhibition studies confirmed the involvement of the classic Ras-Raf-MEK–extracellular signal-regulated kinase (Ras-Raf-MEK-ERK) pathway in FucT-VII induction by PMA, Ras, and Raf. These studies also revealed a second, Ras-induced, Raf-1–independent pathway that participated in induction of FucT-VII. Strong activation of Ras represents a major pathway for induction of FucT-VII gene expression in T cells.

scholarly journals Conditional transformation of cells and rapid activation of the mitogen-activated protein kinase cascade by an estradiol-dependent human raf-1 protein kinase.

1993 ◽  
Vol 13 (10) ◽  
pp. 6241-6252 ◽  
Author(s):  
M L Samuels ◽  
M J Weber ◽  
J M Bishop ◽  
M McMahon
Keyword(s):  
Protein Kinase ◽  
Map Kinase ◽  
Map Kinases ◽  
Growth Media ◽  
Hormone Binding ◽  
Map Kinase Cascade ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
Hormone Binding Domain ◽  
Map Kinase Kinase

We report a strategy for regulating the activity of a cytoplasmic signaling molecule, the protein kinase encoded by raf-1. Retroviruses encoding a gene fusion between an oncogenic form of human p74raf-1 and the hormone-binding domain of the human estrogen receptor (hrafER) were constructed. The fusion protein was nontransforming in the absence of estradiol but could be reversibly activated by the addition or removal of estradiol from the growth media. Activation of hrafER was accompanied in C7 3T3 cells by the rapid, protein synthesis-independent activation of both mitogen-activated protein (MAP) kinase kinase and p42/p44 MAP kinase and by phosphorylation of the resident p74raf-1 protein as demonstrated by decreased electrophoretic mobility. The phosphorylation of p74raf-1 had no effect on the kinase activity of the protein, indicating that mobility shift is an unreliable indicator of p74raf-1 enzymatic activity. Removal of estradiol from the growth media led to a rapid inactivation of the MAP kinase cascade. These results demonstrate that Raf-1 can activate the MAP kinase cascade in vivo, independent of other "upstream" signaling components. Parallel experiments performed with rat1a cells conditionally transformed by hrafER demonstrated activation of MAP kinase kinase in response to estradiol but no subsequent activation of p42/p44 MAP kinases or phosphorylation of p74raf-1. This result suggests that in rat1a cells, p42/p44 MAP kinase activation is not required for Raf-1-mediated oncogenic transformation. Estradiol-dependent activation of p42/p44 MAP kinases and phosphorylation of p74raf-1 was, however, observed in rat1a cells expressing hrafER when the cells were pretreated with okadaic acid. This result suggests that the level of protein phosphatase activity may play a crucial role in the regulation of the MAP kinase cascade. Our results provide the first example of a cytosolic signal transducer being harnessed by fusion to the hormone-binding domain of the estrogen receptor. This conditional system not only will aid the elucidation of the function of Raf-1 but also may be more broadly useful for the construction of conditional forms of other kinases and signaling molecules.

scholarly journals Interaction of Rac Exchange Factors Tiam1 and Ras-GRF1 with a Scaffold for the p38 Mitogen-Activated Protein Kinase Cascade

2002 ◽  
Vol 22 (12) ◽  
pp. 4073-4085 ◽  
Author(s):  
Rachel J. Buchsbaum ◽  
Beth A. Connolly ◽  
Larry A. Feig
Keyword(s):  
Map Kinase ◽  
P38 Map Kinase ◽  
Mitogen Activated Protein Kinase ◽  
Nucleotide Exchange ◽  
Rac Gtpase ◽  
Signaling Specificity ◽  
Map Kinase Cascade ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
In Cells

ABSTRACT Tiam1 and Ras-GRF1 are guanine nucleotide exchange factors (GEFs) that activate the Rac GTPase. The two GEFs have similar N-terminal regions containing pleckstrin homology domains followed by coiled-coils and additional sequences that function together to allow regulated GEF activity. Here we show that this N-terminal region of both proteins binds to the scaffold protein IB2/JIP2. IB2/JIP2 is a scaffold for the p38 mitogen-activated protein (MAP) kinase cascade because it binds to the Rac target MLK3, the MAP kinase kinase MKK3, and the p38 MAP kinase. Expression of IB2/JIP2 in cells potentiates the ability of Tiam1 or Ras-GRF1 to activate the p38 MAP kinase cascade but not the Jnk MAP kinase cascade. In addition, Tiam1 or Ras-GRF1 binding to IB2/JIP2 increases the association of the components of the p38 MAP kinase signaling cassette with IB2/JIP2 in cells and activates scaffold-associated p38. These findings imply that Tiam1 and Ras-GRF1 can contribute to Rac signaling specificity by their ability to form a complex with a scaffold that binds components of one of the many known Rac effector pathways.

scholarly journals The Ustilago maydis ubc4 and ubc5 Genes Encode Members of a MAP Kinase Cascade Required for Filamentous Growth

2000 ◽  
Vol 13 (7) ◽  
pp. 781-786 ◽  
Author(s):  
David L. Andrews ◽  
John D. Egan ◽  
María E. Mayorga ◽  
Scott E. Gold
Keyword(s):  
Map Kinase ◽  
Ustilago Maydis ◽  
Filamentous Growth ◽  
Mitogen Activated Protein Kinase ◽  
Genetic Determinants ◽  
Map Kinase Cascade ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
Suppressor Mutants ◽  
Corn Smut

Ustilago maydis, the causal agent of corn smut disease, displays dimorphic growth in which it alternates between a budding haploid saprophyte and a filamentous dikaryotic pathogen. We are interested in identifying the genetic determinants of filamentous growth and pathogenicity in U. maydis. To do this we have taken a forward genetic approach. Earlier, we showed that haploid adenylate cyclase (uac1) mutants display a constitutively filamentous phenotype. Mutagenesis of a uac1 disruption strain allowed the isolation of a large number of budding suppressor mutants. These mutants are named ubc, for Ustilago bypass of cyclase, as they no longer require the production of cyclic AMP (cAMP) to grow in the budding morphology. Complementation of a subset of these suppressor mutants led to the identification of the ubc4 and ubc5 genes, which are required for filamentous growth and encode a MAP (mitogen-activated protein) kinase kinase kinase and a MAP kinase kinase, respectively. Evidence suggests that they are important in the pheromone response pathway and in pathogenicity. These results further support an important interplay of the cAMP and MAP kinase signal transduction pathways in the control of morphogenesis and pathogenicity in U. maydis.

scholarly journals Legionella pneumophila Suppresses Macrophage Interleukin-12 Production by Activating the p42/44 Mitogen-Activated Protein Kinase Cascade

2003 ◽  
Vol 71 (11) ◽  
pp. 6672-6675 ◽  
Author(s):  
Kazuto Matsunaga ◽  
Hiroyuki Yamaguchi ◽  
Thomas W. Klein ◽  
Herman Friedman ◽  
Yoshimasa Yamamoto
Keyword(s):  
Map Kinase ◽  
Legionella Pneumophila ◽  
Kinase Inhibitors ◽  
Selective Inhibition ◽  
P38 Map Kinase ◽  
Mitogen Activated Protein Kinase ◽  
Interleukin 12 ◽  
Map Kinase Cascade ◽  
Mitogen Activated Protein ◽  
Kinase Cascade

ABSTRACT A possible involvement of the mitogen-activated protein (MAP) kinase cascade in the inhibition of macrophage interleukin-12 (IL-12) production by Legionella pneumophila infection was examined. The results of MAP kinase inhibition by p42/44 and p38 MAP kinase inhibitors and of p42/44 MAP kinase activity assays indicate that L. pneumophila infection of macrophages causes a selective inhibition of lipopolysaccharide-induced IL-12 production by activating the p42/44 MAP kinase cascade. In addition, it was also revealed that the p38 MAP kinase may be important for the production of IL-12 but not for the inhibition caused by L. pneumophila infection.

Conditional transformation of cells and rapid activation of the mitogen-activated protein kinase cascade by an estradiol-dependent human raf-1 protein kinase

1993 ◽  
Vol 13 (10) ◽  
pp. 6241-6252
Author(s):  
M L Samuels ◽  
M J Weber ◽  
J M Bishop ◽  
M McMahon
Keyword(s):  
Protein Kinase ◽  
Map Kinase ◽  
Map Kinases ◽  
Growth Media ◽  
Hormone Binding ◽  
Map Kinase Cascade ◽  
Mitogen Activated Protein ◽  
Kinase Cascade ◽  
Hormone Binding Domain ◽  
Map Kinase Kinase

We report a strategy for regulating the activity of a cytoplasmic signaling molecule, the protein kinase encoded by raf-1. Retroviruses encoding a gene fusion between an oncogenic form of human p74raf-1 and the hormone-binding domain of the human estrogen receptor (hrafER) were constructed. The fusion protein was nontransforming in the absence of estradiol but could be reversibly activated by the addition or removal of estradiol from the growth media. Activation of hrafER was accompanied in C7 3T3 cells by the rapid, protein synthesis-independent activation of both mitogen-activated protein (MAP) kinase kinase and p42/p44 MAP kinase and by phosphorylation of the resident p74raf-1 protein as demonstrated by decreased electrophoretic mobility. The phosphorylation of p74raf-1 had no effect on the kinase activity of the protein, indicating that mobility shift is an unreliable indicator of p74raf-1 enzymatic activity. Removal of estradiol from the growth media led to a rapid inactivation of the MAP kinase cascade. These results demonstrate that Raf-1 can activate the MAP kinase cascade in vivo, independent of other "upstream" signaling components. Parallel experiments performed with rat1a cells conditionally transformed by hrafER demonstrated activation of MAP kinase kinase in response to estradiol but no subsequent activation of p42/p44 MAP kinases or phosphorylation of p74raf-1. This result suggests that in rat1a cells, p42/p44 MAP kinase activation is not required for Raf-1-mediated oncogenic transformation. Estradiol-dependent activation of p42/p44 MAP kinases and phosphorylation of p74raf-1 was, however, observed in rat1a cells expressing hrafER when the cells were pretreated with okadaic acid. This result suggests that the level of protein phosphatase activity may play a crucial role in the regulation of the MAP kinase cascade. Our results provide the first example of a cytosolic signal transducer being harnessed by fusion to the hormone-binding domain of the estrogen receptor. This conditional system not only will aid the elucidation of the function of Raf-1 but also may be more broadly useful for the construction of conditional forms of other kinases and signaling molecules.

The mitogen-activated protein kinase cascade is activated by B-Raf in response to nerve growth factor through interaction with p21ras

1994 ◽  
Vol 14 (10) ◽  
pp. 6944-6953
Author(s):  
R K Jaiswal ◽  
S A Moodie ◽  
A Wolfman ◽  
G E Landreth
Keyword(s):  
Nerve Growth Factor ◽  
Growth Factor ◽  
Map Kinase ◽  
Pc12 Cells ◽  
Mitogen Activated Protein Kinase ◽  
Stable Complex ◽  
Nerve Growth ◽  
Map Kinase Cascade ◽  
Mitogen Activated Protein ◽  
Kinase Cascade

Nerve growth factor (NGF) activates the mitogen-activated protein (MAP) kinase cascade through a p21ras-dependent signal transduction pathway in PC12 cells. The linkage between p21ras and MEK1 was investigated to identify those elements which participate in the regulation of MEK1 activity. We have screened for MEK activators using a coupled assay in which the MAP kinase cascade has been reconstituted in vitro. We report that we have detected a single NGF-stimulated MEK-activating activity which has been identified as B-Raf. PC12 cells express both B-Raf and c-Raf1; however, the MEK-activating activity was found only in fractions containing B-Raf. c-Raf1-containing fractions did not exhibit a MEK-activating activity. Gel filtration analysis revealed that the B-Raf eluted with an apparent M(r) of 250,000 to 300,000, indicating that it is present within a stable complex with other unidentified proteins. Immunoprecipitation with B-Raf-specific antisera quantitatively precipitated all MEK activator activity from these fractions. We also demonstrate that B-Raf, as well as c-Raf1, directly interacted with activated p21ras immobilized on silica beads. NGF treatment of the cells had no effect on the ability of B-Raf or c-Raf1 to bind to activated p21ras. These data indicate that this interaction was not dependent upon the activation state of these enzymes; however, MEK kinase activity was found to be associated with p21ras following incubation with NGF-treated samples at levels higher than those obtained from unstimulated cells. These data provide direct evidence that NGF-stimulated B-Raf is responsible for the activation of the MAP kinase cascade in PC12 cells, whereas c-Raf1 activity was not found to function within this pathway.

scholarly journals Structurally unique interaction of RBD-like and PH domains is crucial for yeast pheromone signaling

2013 ◽  
Vol 24 (3) ◽  
pp. 409-420 ◽  
Author(s):  
Volodymyr Yerko ◽  
Traian Sulea ◽  
Irena Ekiel ◽  
Doreen Harcus ◽  
Jason Baardsnes ◽  
...  
Keyword(s):  
Map Kinase ◽  
Ph Domain ◽  
Yeast Saccharomyces Cerevisiae ◽  
Kinase Activation ◽  
Functional Studies ◽  
Pheromone Signaling ◽  
Map Kinase Cascade ◽  
Evolutionarily Conserved ◽  
Mitogen Activated Protein ◽  
Kinase Cascade

The Ste5 protein forms a scaffold that associates and regulates the components of the mitogen-activated protein (MAP) kinase cascade that controls mating-pheromone-mediated signaling in the yeast Saccharomyces cerevisiae. Although it is known that the MEK kinase of the pathway, Ste11, associates with Ste5, details of this interaction have not been established. We identified a Ras-binding-domain-like (RBL) region in the Ste11 protein that is required specifically for the kinase to function in the mating pathway. This module is structurally related to domains in other proteins that mediate Ras-MAP kinase kinase kinase associations; however, this RBL module does not interact with Ras, but instead binds the PH domain of the Ste5 scaffold. Structural and functional studies suggest that the key role of this PH domain is to mediate the Ste5–Ste11 interaction. Overall these two evolutionarily conserved modules interact with each other through a unique interface, and thus in the pheromone pathway the structural context of the RBL domain contribution to kinase activation has been shifted through a change of its interaction partner from Ras to a PH domain.

scholarly journals A Novel Regulatory Mechanism in the Mitogen-activated Protein (MAP) Kinase Cascade

1997 ◽  
Vol 272 (51) ◽  
pp. 32642-32648 ◽  
Author(s):  
Makoto Fukuda ◽  
Isamu Gotoh ◽  
Makoto Adachi ◽  
Yukiko Gotoh ◽  
Eisuke Nishida
Keyword(s):  
Map Kinase ◽  
Regulatory Mechanism ◽  
Map Kinase Cascade ◽  
Protein Map ◽  
Mitogen Activated Protein ◽  
Kinase Cascade

scholarly journals Methylglyoxal Activates the Target of Rapamycin Complex 2-Protein Kinase C Signaling Pathway in Saccharomyces cerevisiae

2015 ◽  
Vol 35 (7) ◽  
pp. 1269-1280 ◽  
Author(s):  
Wataru Nomura ◽  
Yoshiharu Inoue
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Map Kinase ◽  
Target Of Rapamycin ◽  
Dependent Manner ◽  
Content Type ◽  
Protein Levels ◽  
Map Kinase Cascade ◽  
Phosphorylated Akt ◽  
Mitogen Activated Protein ◽  
Kinase Cascade

Methylglyoxal is a typical 2-oxoaldehyde derived from glycolysis. We show here that methylglyoxal activates the Pkc1-Mpk1 mitogen-activated protein (MAP) kinase cascade in a target of rapamycin complex 2 (TORC2)-dependent manner in the budding yeastSaccharomyces cerevisiae. We demonstrate that TORC2 phosphorylates Pkc1 at Thr1125and Ser1143. Methylglyoxal enhanced the phosphorylation of Pkc1 at Ser1143, which transmitted the signal to the downstream Mpk1 MAP kinase cascade. We found that the phosphorylation status of Pkc1T1125affected the phosphorylation of Pkc1 at Ser1143, in addition to its protein levels. Methylglyoxal activated mammalian TORC2 signaling, which, in turn, phosphorylated Akt at Ser473. Our results suggest that methylglyoxal is a conserved initiator of TORC2 signaling among eukaryotes.

Sign in / Sign up

Export Citation Format

Share Document