Combined computational and experimental analysis reveals mitogen-activated protein kinase–mediated feedback phosphorylation as a mechanism for signaling specificity

Different environmental stimuli often use the same set of signaling proteins to achieve very different physiological outcomes. The mating and invasive growth pathways in yeast each employ a mitogen-activated protein (MAP) kinase cascade that includes Ste20, Ste11, and Ste7. Whereas proper mating requires Ste7 activation of the MAP kinase Fus3, invasive growth requires activation of the alternate MAP kinase Kss1. To determine how MAP kinase specificity is achieved, we used a series of mathematical models to quantitatively characterize pheromone-stimulated kinase activation. In accordance with the computational analysis, MAP kinase feedback phosphorylation of Ste7 results in diminished activation of Kss1, but not Fus3. These findings reveal how feedback phosphorylation of a common pathway component can limit the activity of a competing MAP kinase through feedback phosphorylation of a common activator, and thereby promote signal fidelity.

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

Molecular and Cellular Biology ◽

10.1128/mcb.22.12.4073-4085.2002 ◽

2002 ◽

Vol 22 (12) ◽

pp. 4073-4085 ◽

Cited By ~ 131

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.

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The Stress-activated Mitogen-activated Protein Kinase Signaling Cascade Promotes Exit from Mitosis

Molecular Biology of the Cell ◽

10.1091/mbc.e05-12-1102 ◽

2006 ◽

Vol 17 (7) ◽

pp. 3136-3146 ◽

Cited By ~ 23

Author(s):

Vladimír Reiser ◽

Katharine E. D’Aquino ◽

Ly-Sha Ee ◽

Angelika Amon

Keyword(s):

Map Kinase ◽

Mitogen Activated Protein Kinase ◽

Hog Pathway ◽

Hypertonic Stress ◽

Map Kinase Cascade ◽

Protein Map ◽

Mitogen Activated Protein ◽

Early Anaphase ◽

Kinase Cascade ◽

Protein Kinase Signaling

In budding yeast, a signaling network known as the mitotic exit network (MEN) triggers exit from mitosis. We find that hypertonic stress allows MEN mutants to exit from mitosis in a manner dependent on the high osmolarity glycerol (HOG) mitogen-activated protein (MAP) kinase cascade. The HOG pathway drives exit from mitosis in MEN mutants by promoting the activation of the MEN effector, the protein phosphatase Cdc14. Activation of Cdc14 depends on the Cdc14 early anaphase release network, a group of proteins that functions in parallel to the MEN to promote Cdc14 function. Notably, exit from mitosis is promoted by the signaling branch defined by the Sho1 osmosensing system, but not by the Sln1 osmosensor of the HOG pathway. Our results suggest that the stress MAP kinase pathway mobilizes programs to promote completion of the cell cycle and entry into G1 under unfavorable conditions.

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Role of a Mitogen-Activated Protein Kinase Cascade in Ion Flux-Mediated Turgor Regulation in Fungi

Eukaryotic Cell ◽

10.1128/ec.5.3.480-487.2006 ◽

2006 ◽

Vol 5 (3) ◽

pp. 480-487 ◽

Cited By ~ 34

Author(s):

Roger R. Lew ◽

Natalia N. Levina ◽

Lana Shabala ◽

Marinela I. Anderca ◽

Sergey N. Shabala

Keyword(s):

Map Kinase ◽

Mitogen Activated Protein Kinase ◽

Wild Type ◽

Turgor Regulation ◽

Map Kinase Cascade ◽

Protein Map ◽

Mitogen Activated Protein ◽

Kinase Cascade ◽

Protein Kinase Cascade

ABSTRACT Fungi normally maintain a high internal hydrostatic pressure (turgor) of about 500 kPa. In response to hyperosmotic shock, there are immediate electrical changes: a transient depolarization (1 to 2 min) followed by a sustained hyperpolarization (5 to 10 min) prior to turgor recovery (10 to 60 min). Using ion-selective vibrating probes, we established that the transient depolarization is due to Ca2+ influx and the sustained hyperpolarization is due to H+ efflux by activation of the plasma membrane H+-ATPase. Protein synthesis is not required for H+-ATPase activation. Net K+ and Cl− uptake occurs at the same time as turgor recovery. The magnitude of the ion uptake is more than sufficient to account for the osmotic gradients required for turgor to return to its original level. Two osmotic mutants, os-1 and os-2, homologs of a two-component histidine kinase sensor and the yeast high osmotic glycerol mitogen-activated protein (MAP) kinase, respectively, have lower turgor than the wild type and do not exhibit the sustained hyperpolarization after hyperosmotic treatment. The os-1 mutant does not exhibit all of the wild-type turgor-adaptive ion fluxes (Cl− uptake increases, but net K+ flux barely changes and net H+ efflux declines) (os-2 was not examined). Both os mutants are able to regulate turgor but at a lower level than the wild type. Our results demonstrate that a MAP kinase cascade regulates ion transport, activation of the H+-ATPase, and net K+ and Cl− uptake during turgor regulation. Other pathways regulating turgor must also exist.

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Genetic Analysis of rolled, Which Encodes a Drosophila Mitogen-Activated Protein Kinase

Genetics ◽

10.1093/genetics/153.2.763 ◽

1999 ◽

Vol 153 (2) ◽

pp. 763-771 ◽

Cited By ~ 1

Author(s):

Young-Mi Lim ◽

Kimiko Nishizawa ◽

Yoshimi Nishi ◽

Leo Tsuda ◽

Yoshihiro H Inoue ◽

...

Keyword(s):

Map Kinase ◽

Mitogen Activated Protein Kinase ◽

Female Sterility ◽

Tor Signaling ◽

Map Kinase Cascade ◽

Dominant Female ◽

Protein Map ◽

Mitogen Activated Protein ◽

Kinase Cascade

Abstract Genetic and molecular characterization of the dominant suppressors of D-rafC110 on the second chromosome identified two gain-of-function alleles of rolled (rl), which encodes a mitogen-activated protein (MAP) kinase in Drosophila. One of the alleles, rlSu23, was found to bear the same molecular lesion as rlSem, which has been reported to be dominant female sterile. However, rlSu23 and the current stock of rlSem showed only a weak dominant female sterility. Detailed analyses of the rl mutations demonstrated moderate dominant activities of these alleles in the Torso (Tor) signaling pathway, which explains the weak dominant female sterility observed in this study. The dominant rl mutations failed to suppress the terminal class maternal-effect mutations, suggesting that activation of Rl is essential, but not sufficient, for Tor signaling. Involvement of rl in cell proliferation was also demonstrated by clonal analysis. Branching and integration of signals in the MAP kinase cascade is discussed.

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Activation of MAP kinase and translocation with HSP27 in bombesin-induced contraction of rectosigmoid smooth muscle

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1995.269.5.g683 ◽

1995 ◽

Vol 269 (5) ◽

pp. G683-G691 ◽

Cited By ~ 14

Author(s):

H. Yamada ◽

J. Strahler ◽

M. J. Welsh ◽

K. N. Bitar

Keyword(s):

Smooth Muscle ◽

Map Kinase ◽

Resting Cells ◽

Kinase Activation ◽

Sustained Contraction ◽

Contraction Map ◽

Map Kinase Cascade ◽

Protein Map ◽

Mitogen Activated Protein ◽

Kinase Cascade

We have investigated whether mitogen-activated protein (MAP) kinase cascade is essential for sustained contraction of smooth muscle cells of the rabbit rectosigmoid. We have identified MAP kinase as one of the enzymes activated by bombesin, performed immunologic studies blocking the activation of MAP kinase, and conducted confocal localization of MAP kinase in relation to heat-shock protein (HSP27), postulated to be involved in the sustained contraction of smooth muscle. Immunoblotting revealed two forms of MAP kinase (42 and 44 kDa). Activation of MAP kinase by bombesin was rapid, reaching a maximum in 30 s and subsequently declining. [D-Phe6,Leu13,psi(CH2NH),Phe14]BN-(6-14), a potent bombesin antagonist, and protein kinase C (PKC) inhibitors 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine, calphostin C, and chelerythrine inhibited the increase in MAP kinase induced by bombesin. Immunofluorescent dual labeling and confocal microscopy indicate that these two proteins are closely distributed in resting cells and that during bombesin-induced contraction MAP kinase translocates accompanied by HSP27. In conclusion, a series of events involving PKC activation, MAP kinase activation, and MAP kinase-HSP27 translocation could be the signaling pathway involved in bombesin-induced sustained contraction.

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

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2000.13.7.781 ◽

2000 ◽

Vol 13 (7) ◽

pp. 781-786 ◽

Cited By ~ 81

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.

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

Infection and Immunity ◽

10.1128/iai.71.11.6672-6675.2003 ◽

2003 ◽

Vol 71 (11) ◽

pp. 6672-6675 ◽

Cited By ~ 9

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.

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

Molecular and Cellular Biology ◽

10.1128/mcb.14.10.6944-6953.1994 ◽

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.

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

Molecular Biology of the Cell ◽

10.1091/mbc.e12-07-0516 ◽

2013 ◽

Vol 24 (3) ◽

pp. 409-420 ◽

Cited By ~ 2

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.

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