Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P05231 (interleukin-6)
 23,907 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intercellular adhesion molecule-1 (ICAM-1) is a transmembrane glycoprotein that promotes adhesion in immunological and inflammatory reactions. ICAM-1 is expressed on cells of many lineages and is induced by interleukin-6 (IL-6) and interferon-gamma (IFN-gamma). Functional analysis of ICAM-1 promoter-luciferase constructs in HepG2 cells enabled us to identify a region between -110 and -37 mediating IL-6 and IFN-gamma responsiveness and containing a palindromic IL-6/IFN-gamma response element (pIRE). Site-directed mutagenesis of key nucleotides in the ICAM-1 pIRE abolished the effect of both IL-6 and IFN-gamma stimulation, while this pIRE element was sufficient to confer IL-6 and IFN-gamma responsiveness to a heterologous promoter. We further show by gel retardation analysis that distinct nuclear factors induced by both IL-6 or IFN-gamma specifically bind to this pIRE. Furthermore, treatment with IL-6 results in the formation of multiple complexes while IFN-gamma induces a single binding complex, both in HepG2 and monocytic U937 cells. Differentiation of U937 cells by exposure to 12-O-tetradecanoyl phorbol-13-acetate abolishes response to IL-6 but not IFN-gamma. Supershift data utilizing the ICAM-1 pIRE revealed that IFN-gamma and IL-6 both induce a factor antigenically related to IFN-gamma activation factor. We further provide data suggesting that IL-6 additionally activates an ICAM-1 pIRE binding factor related to the previously described acute-phase response factor in disparate cell types. We therefore conclude that the activation of these related nuclear factors by IL-6 and IFN-gamma is important in the regulation of ICAM-1 gene expression.
 ...
PMID:Stimulation of the human intercellular adhesion molecule-1 promoter by interleukin-6 and interferon-gamma involves binding of distinct factors to a palindromic response element. 791 91

Human intercellular adhesion molecule-1 (ICAM-1), a transmembrane glycoprotein that functions as a ligand for lymphocyte function-associated antigen-1, plays an important role in mediating cell-cell interactions in inflammatory reactions. It is induced by proinflammatory cytokines such as interleukin-1, tumor necrosis factor-alpha or interferon-gamma, as well as by phorbol esters, retinoic acid and lipopolysaccharide. Furthermore, ICAM-1 is upregulated by interleukin-6, which suggests that it belongs to the family of acute phase response genes. Investigation of the 5'-regulatory region of the human ICAM-1 gene revealed sequence motifs for a variety of transcription factors implicated in transcriptional regulation. This review summarizes the current knowledge of the transcriptional regulation of the human ICAM-1 gene.
 ...
PMID:Transcriptional regulation of the human intercellular adhesion molecule-1 gene: a short overview. 853 Jan 58

The c-met protooncogene encodes a transmembrane tyrosine kinase receptor for hepatocyte growth factor (HGF). It has been widely suggested that HGF and its receptor constitute a paracrine signaling system, in which mesenchymally derived cells produce ligand that binds to the receptor predominantly expressed on cells of epithelial origin. In this study, we have isolated and completely sequenced the entire coding region of c-met cDNA from the rat kidney. The nucleotide sequence of the rat c-met cDNA revealed that the HGF receptor is encoded within single open-reading frame as 190 kDa of a transmembrane glycoprotein consisting of 1,382 amino acids. Determination of c-met mRNA levels in various tissues revealed a widespread expression of c-met with the highest levels in kidney, lung, and liver. We found simultaneous induction of both HGF and its receptor gene expression by interleukin-6 (IL-6) in primary cultured rat glomerular mesangial cells. The expression of HGF and c-met was remarkably stimulated following incubation of rat mesangial cells with IL-6, in a time- and dose-dependent manner Our data suggest that autocrine action of HGF may be achieved in vivo through simultaneous induction of both HGF and its receptor expression in renal mesenchymal cells.
 ...
PMID:Primary structure of rat HGF receptor and induced expression in glomerular mesangial cells. 885 31

Binding of interleukin-6 to its receptor (IL-6R) induces the association of the IL-6R alpha chain (IL-6Ralpha) with a 130-kDa transmembrane glycoprotein, gp130. This event activates tyrosine kinases of the Janus kinase (JAK) family and transduces signals to the cytosol or nucleus. To further characterize the biochemical mechanisms by which IL-6 promotes cell proliferation, we investigated the effects of IL-6 on the growth and transmembrane signaling of several lymphoid cell lines. In the IL-6-dependent cell line B-9, IL-6 induced a rapid, transient, and concentration-dependent tyrosine phosphorylation of several cytosolic proteins as detected by antiphosphotyrosine immunoblots. The molecular weight of major bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was 44, 65, 70, 80, 137, 148, 184, and 190 kDa, respectively. Similar effects of IL-6 on tyrosine phosphorylation were observed in the human multiple myeloma cell line LP-1. Because JAKs were unlikely to mediate all the biological effects of IL-6, we investigated whether members of the Src family of tyrosine kinases were also activated in B-9 or LP-1 cells. IL-6 induced the activation and tyrosine phosphorylation of p59Fyn, p56/59Hck, and p56Lyn. Coprecipitation experiments with anti-Hck, anti-Lyn, anti-Fyn, and anti-gp130 antibodies revealed a physical association with gp130 of p56/59Hck and p56Lyn, but not p59Fyn, in LP-1 cells. Together, these results show for the first time that several Src kinases may become activated by IL-6 (p59Fyn, p56/59Hck, and p56Lyn) and associate with gp130 (p56/59Hck and p56Lyn).
 ...
PMID:Signal transduction of interleukin-6 involves tyrosine phosphorylation of multiple cytosolic proteins and activation of Src-family kinases Fyn, Hck, and Lyn in multiple myeloma cell lines. 940 96

The transmembrane glycoprotein gp130 is involved in many cytokine-mediated cellular responses and acts therein as the signal transducing receptor subunit. Interleukin-6 (IL-6) and interleukin-11 (IL-11), in complex with their specific alpha-receptors, homodimerize gp130 and, as a consequence, activate the Janus kinase (Jak)/signal transducer and activator of transcription (STAT) signalling pathway in their target cells. So far, it is not clear whether gp130 is bound to these cytokines and their specific alpha-receptor subunits through identical or different epitopes. In order to study the interaction of IL-11 and IL-11R with human gp130 the soluble form of the recently cloned human IL-11R was expressed in baculovirus-infected insect cells. By a coprecipitation binding-assay it is demonstrated that IL-11 and IL-6 compete for binding to gp130. Using deletion and point mutants of gp130 it is shown that IL-11-IL-11R and IL-6-IL-6R recognize overlapping binding motifs on gp130. Moreover, using well-established Jak-deficient cell lines we demonstrate that STAT activation by IL-11 requires Jak1. Taken together, our data support the concept that IL-6 and IL-11 activate gp130 by very similar molecular mechanisms.
 ...
PMID:Activation of the signal transducer gp130 by interleukin-11 and interleukin-6 is mediated by similar molecular interactions. 956 Feb 94

The transmembrane glycoprotein gp130 is the common signal transducing receptor subunit of the interleukin-6-type cytokines. It is a member of the cytokine-receptor superfamily predicted to consist of six domains in its extracellular part. The second and third domain constitute the cytokine-binding module defined by a set of four conserved cysteines and a WSXWS motif, respectively. The three-dimensional structure of the carboxy-terminal domain of this region was determined by multidimensional NMR. The domain consists of seven beta-strands constituting a fibronectin type III-like topology. The structure reveals that the WSDWS motif of gp130 is part of an extended tryptophan/arginine zipper which modulates the conformation of the CD loop.
 ...
PMID:The signal transducer gp130: solution structure of the carboxy-terminal domain of the cytokine receptor homology region. 1021 Jan 78

The transmembrane glycoprotein gp130 belongs to the family of hematopoietic cytokine receptors. It represents the common signal transducing receptor component of the so called interleukin-6-type cytokines. For several cytokine receptors including gp130 it has been shown that receptor activation cannot only be achieved by the natural ligand but also by single monoclonal antibodies raised against the receptor ectodomain. These findings have been interpreted in a way that dimerization of cytokine receptors is sufficient for receptor activation. Here we show that the recently described gp130-activating antibody B-S12 actually consists of two different monoclonal antibodies. By subcloning of B-S12 the monoclonal antibodies B-S12-A5 and B-S12-G7 were obtained. The individual antibodies are biologically inactive, in combination they exert B-S12-like activity on hepatoma cells. On Ba/F3 cells stably transfected with gp130 a combination of B-S12-G7 with another monoclonal gp130 antibody, B-P8, is required to stimulate proliferation. Using gp130 deletion mutants we show that all three antibodies map to domains 2 and 3 of gp130 which constitute the cytokine binding module. The individual antibodies inhibit activation of the signal transducer by interleukin-6 and interfere with binding of interleukin-6 to gp130. Interestingly, the combination of B-S12-G7 and a Fab fragment of B-P8 retains biological activity. We conclude from our data that (i) the monoclonal antibodies activate gp130 by mimicking the natural ligand and (ii) enforcement of gp130 dimerization is not sufficient for receptor activation but additional conformational requirements have to be fulfilled.
 ...
PMID:Studies on the interleukin-6-type cytokine signal transducer gp130 reveal a novel mechanism of receptor activation by monoclonal antibodies. 1067 83

Ebola virus, a member of the family Filoviridae, causes one of the most severe forms of viral hemorrhagic fever. In the terminal stages of disease, symptoms progress to hypotension, coagulation disorders, and hemorrhages, and there is prominent involvement of the mononuclear phagocytic and reticuloendothelial systems. Cells of the mononuclear phagocytic system are primary target cells and producers of inflammatory mediators. Ebola virus efficiently produces four soluble glycoproteins during infection: sGP, delta peptide (Delta-peptide), GP(1), and GP(1,2Delta). While the presence of these glycoproteins has been confirmed in blood (sGP) and in vitro systems, it is hypothesized that they are of biological relevance in pathogenesis, particularly target cell activation. To gain insight into their function, we expressed the four soluble glycoproteins in mammalian cells and purified and characterized them. The role of the transmembrane glycoprotein in the context of virus-like particles was also investigated. Primary human macrophages were treated with glycoproteins and virus-like particles and subsequently tested for activation by detection of several critical proinflammatory cytokines (tumor necrosis factor alpha, interleukin-6 [IL-6], and IL-1 beta) and the chemokine IL-8. The presentation of the glycoprotein was determined to be critical since virus-like particles, but not soluble glycoproteins, induced high levels of activation. We propose that the presentation of GP(1,2) in the rigid form such as that observed on the surface of particles is critical for initiating a sufficient signal for the activation of primary target cells. The secreted glycoproteins do not appear to play any role in exogenous activation of these cells during Ebola virus infection.
 ...
PMID:Role of Ebola virus secreted glycoproteins and virus-like particles in activation of human macrophages. 1568 42

Tissue factor (TF) is a transmembrane glycoprotein that binds its zymogen cofactor, Factor VIIa (FVIIa) on the cell surface. Together (TF/FVIIa) they activate Factor X (FX) and Factor IX (FIX) and start the extrinsic pathway of blood coagulation. As such, the TF/FVIIa complex plays an important role in normal physiology as well as in thrombotic diseases such as unstable angina (UA), disseminated intravascular coagulation (DIC), and deep vein thrombosis (DVT). In addition to its function as an initiator of coagulation, TF/FVIIa plays an important role in inflammation. Expression of TF on the cell surface and its appearance as a soluble molecule are characteristic features of acute and chronic inflammation in conditions such as sepsis and atherosclerosis. Here we demonstrate that BCX-3607, a small molecule potent inhibitor of TF/FVIIa, reduces thrombus weight in an animal model of DVT. BCX-3607 also decreases the level of interleukin-6 (IL-6) in a LPS-stimulated mouse model of endotoxemia. Additionally, in vitro studies indicate that BCX-3607 blocks the generation of TF/FVIIa-induced IL-8 mRNA in human keratinocytes and reduces the TF/FVIIa-mediated generation of IL-6 and IL-8 in human umbilical vein endothelial cells (HUVEC). Therefore, BCX-3607 might block the TF/FVIIa-mediated coagulation and inflammation associated with pathological conditions.
 ...
PMID:The antithrombotic and anti-inflammatory effects of BCX-3607, a small molecule tissue factor/factor VIIa inhibitor. 1637 35

The transmembrane glycoprotein signal regulatory protein/SHP2-substrate (SIRP1alpha/SHPS-1) has been implicated in growth factor- and cell adhesion-induced signalling. Here we report on the contribution of SIRP1alpha to IL-6 type cytokine signalling. SIRP1alpha binds the protein tyrosine phosphatase SHP2 upon treatment with interleukin-6 in a stimulation-dependent manner. Mouse embryonic fibroblasts expressing a SIRP1alpha protein which lacks the intracellular part show enhanced SHP2 phosphorylation and ERK1/2 activation in response to IL-6, suggesting that SIRP1alpha affects IL-6-signalling through SHP2. Whereas SHP2 phosphorylation is enhanced in SIRP1alpha-deficient cells STAT3 activation is delayed and STAT3-dependent gene induction is reduced which correlates with reduced STAT3 serine phosphorylation. Our results indicate that SIRP1alpha contributes to IL-6 signalling by counteracting SHP2 phosphorylation which consequently affects ERK-activation and STAT3-dependent transactivation as well as target gene expression. Our observations will help to understand the tight balance of MAPK- and STAT3-activation in response to IL-6 which was found to be misbalanced in many autoimmune diseases, inflammatory proliferative diseases and cancer.
 ...
PMID:SHPS-1/SIRP1alpha contributes to interleukin-6 signalling. 1845 Apr 21


1 2 Next >>