scholarly journals Role of Surface-Exposed Loops of Haemophilus influenzae Protein P2 in the Mitogen-Activated Protein Kinase Cascade

2003 ◽  
Vol 71 (5) ◽  
pp. 2798-2809 ◽  
Author(s):  
Stefania Galdiero ◽  
Domenica Capasso ◽  
Mariateresa Vitiello ◽  
Marina D'Isanto ◽  
Carlo Pedone ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Protein Kinase ◽  
Haemophilus Influenzae ◽  
Outer Membrane ◽  
Synthetic Peptides ◽  
Mitogen Activated Protein Kinase ◽  
Signal Transduction Pathways ◽  
Mapk Pathways ◽  
Mitogen Activated Protein

ABSTRACT The outer membrane of gram-negative bacteria contains several proteins, and some of these proteins, the porins, have numerous biological functions in the interaction with the host; porins are involved in the activation of signal transduction pathways and, in particular, in the activation of the Raf/MEK1-MEK2/mitogen-activated protein kinase (MAPK) cascade. The P2 porin is the most abundant outer membrane protein of Haemophilus influenzae type b. A three-dimensional structural model for P2 was constructed based on the crystal structures of Klebsiella pneumoniae OmpK36 and Escherichia coli PhoE and OmpF. The protein was readily assembled into the β-barrel fold characteristic of porins, despite the low sequence identity with the template proteins. The model provides information on the structural features of P2 and insights relevant for prediction of domains corresponding to surface-exposed loops, which could be involved in the activation of signal transduction pathways. To identify the role of surface-exposed loops, a set of synthetic peptides were synthesized according to the proposed model and were assayed for MEK1-MEK2/MAPK pathway activation. Our results show that synthetic peptides corresponding to surface loops of protein P2 are able to activate the MEK1-MEK2/MAPK pathways like the entire protein, while peptides modeled on internal β strands are unable to induce significant phosphorylation of the MEK1-MEK2/MAPK pathways. In particular, the peptides corresponding to loops L5 (Lys206 to Gly219), L6B (Ser239 to Lys253), and L7 (Thr280 to Lys287) activate, as the whole protein, essentially JNK and p38.

scholarly journals Protein Kinase A and Mitogen-Activated Protein Kinase Pathways Antagonistically Regulate Fission Yeast fbp1Transcription by Employing Different Modes of Action at Two Upstream Activation Sites

2000 ◽  
Vol 20 (17) ◽  
pp. 6426-6434 ◽  
Author(s):  
Lori A. Neely ◽  
Charles S. Hoffman
Keyword(s):  
Signal Transduction ◽  
Transcriptional Regulation ◽  
Protein Kinase ◽  
Mapk Pathway ◽  
Transcriptional Start Site ◽  
Mitogen Activated Protein Kinase ◽  
Signal Transduction Pathways ◽  
Start Site ◽  
Mitogen Activated Protein ◽  
Kinase A

ABSTRACT A significant challenge to our understanding of eukaryotic transcriptional regulation is to determine how multiple signal transduction pathways converge on a single promoter to regulate transcription in divergent fashions. To study this, we have investigated the transcriptional regulation of theSchizosaccharomyces pombe fbp1 gene that is repressed by a cyclic AMP (cAMP)-dependent protein kinase A (PKA) pathway and is activated by a stress-activated mitogen-activated protein kinase (MAPK) pathway. In this study, we identified and characterized twocis-acting elements in the fbp1 promoter required for activation of fbp1 transcription. Upstream activation site 1 (UAS1), located approximately 900 bp from the transcriptional start site, resembles a cAMP response element (CRE) that is the binding site for the atf1-pcr1 heterodimeric transcriptional activator. Binding of this activator to UAS1 is positively regulated by the MAPK pathway and negatively regulated by PKA. UAS2, located approximately 250 bp from the transcriptional start site, resembles a Saccharomyces cerevisiae stress response element. UAS2 is bound by transcriptional activators and repressors regulated by both the PKA and MAPK pathways, although atf1 itself is not present in these complexes. Transcriptional regulation offbp1 promoter constructs containing only UAS1 or UAS2 confirms that the PKA and MAPK regulation is targeted to both sites. We conclude that the PKA and MAPK signal transduction pathways regulatefbp1 transcription at UAS1 and UAS2, but that the antagonistic interactions between these pathways involve different mechanisms at each site.

EXTRAOCULAR CELLULAR PHOTOTRANSDUCTION

2009 ◽  
Vol 02 (01) ◽  
pp. 93-100 ◽  
Author(s):  
LING ZHU ◽  
TIMON CHENG-YI LIU ◽  
MIN WU ◽  
JIAN-QIN YUAN ◽  
TONG-SHENG CHEN
Keyword(s):  
Signal Transduction ◽  
Protein Kinase ◽  
Monochromatic Light ◽  
Mitogen Activated Protein Kinase ◽  
Signal Transduction Pathways ◽  
Mitogen Activated Protein ◽  
Cellular Signal ◽  
Gs Protein ◽  
Almost All ◽  
Relationship Of

Photobiomodulation (PBM) is a modulation of monochromatic light or laser irradiation (LI) on biosystems. It is reviewed from the viewpoint of extraocular phototransduction in this paper. It was found that LI can induce extraocular phototransduction, and there may be an exact correspondence relationship of LI at different wavelengths and in different dose zones, and cellular signal transduction pathways. The signal transduction pathways can be classified into two types so that the Gs protein-mediated pathways belong to pathway 1, and the other pathways such as protein kinase Cs -mediated pathways and mitogen-activated protein kinase-mediated pathways belong to pathway 2. Almost all the present pathways found to mediate PBM belong to pathway 2, but there should be a pathway 1-mediated PBM. The previous studies were rather preliminary, and therefore further work should be done.

scholarly journals Targeting MAPK Signaling in Cancer: Mechanisms of Drug Resistance and Sensitivity

2020 ◽  
Vol 21 (3) ◽  
pp. 1102 ◽  
Author(s):  
Shannon Lee ◽  
Jens Rauch ◽  
Walter Kolch
Keyword(s):  
Drug Sensitivity ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Signal Transduction Pathways ◽  
Erk Pathway ◽  
Mapk Pathways ◽  
Extracellular Signaling ◽  
New Findings ◽  
Mitogen Activated Protein

Mitogen-activated protein kinase (MAPK) pathways represent ubiquitous signal transduction pathways that regulate all aspects of life and are frequently altered in disease. Here, we focus on the role of MAPK pathways in modulating drug sensitivity and resistance in cancer. We briefly discuss new findings in the extracellular signaling-regulated kinase (ERK) pathway, but mainly focus on the mechanisms how stress activated MAPK pathways, such as p38 MAPK and the Jun N-terminal kinases (JNK), impact the response of cancer cells to chemotherapies and targeted therapies. In this context, we also discuss the role of metabolic and epigenetic aberrations and new therapeutic opportunities arising from these changes.

scholarly journals Mitogen-activated protein kinase phosphatase 2, MKP-2, regulates early inflammation in acute lung injury

2012 ◽  
Vol 303 (3) ◽  
pp. L251-L258 ◽  
Author(s):  
Timothy T. Cornell ◽  
Andrew Fleszar ◽  
Walker McHugh ◽  
Neal B. Blatt ◽  
Ann Marie Le Vine ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Protein Kinase ◽  
Lung Injury ◽  
Neutrophil Infiltration ◽  
Mitogen Activated Protein Kinase ◽  
Molecular Response ◽  
Proinflammatory Response ◽  
Mapk Pathways ◽  
Mitogen Activated Protein

Acute lung injury (ALI) is mediated by an early proinflammatory response resulting from either a direct or indirect insult to the lung mediating neutrophil infiltration and consequent disruption of the alveolar capillary membrane ultimately leading to refractory hypoxemia. The mitogen-activated protein kinase (MAPK) pathways are a key component of the molecular response activated by those insults triggering the proinflammatory response in ALI. The MAPK pathways are counterbalanced by a set of dual-specific phosphatases (DUSP) that deactivate the kinases by removing phosphate groups from tyrosine or threonine residues. We have previously shown that one DUSP, MKP-2, regulates the MAPK pathway in a model of sepsis-induced inflammation; however, the role of MKP-2 in modulating the inflammatory response in ALI has not been previously investigated. We utilized both MKP-2-null (MKP-2−/−) mice and MKP-2 knockdown in a murine macrophage cell line to elucidate the role of MKP-2 in regulating inflammation during ALI. Our data demonstrated attenuated proinflammatory cytokine production as well as decreased neutrophil infiltration in the lungs of MKP-2−/− mice following direct, intratracheal LPS. Importantly, when challenged with a viable pathogen, this decrease in neutrophil infiltration did not impact the ability of MKP-2−/− mice to clear either gram-positive or gram-negative bacteria. Furthermore, MKP-2 knockdown led to an attenuated proinflammatory response and was associated with an increase in phosphorylation of ERK and induction of a related DUSP, MKP-1. These data suggest that altering MKP-2 activity may have therapeutic potential to reduce lung inflammation in ALI without impacting pathogen clearance.

Sign in / Sign up

Export Citation Format

Share Document