UNIPROT:P04141 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Target Concepts:

Query: UNIPROT:P04141 (granulocyte-macrophage colony-stimulating factor)
6,790 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Granulocyte-macrophage colony-stimulating factor (GM-CSF), formylmethionylleucylphenylalanine, tumor necrosis factor alpha, platelet-activating factor, phorbol ester (phorbol 12-myristate 13-acetate), and calcium ionophore A23187 are able to increase the level of tyrosine phosphorylation of different protein substrates, as demonstrated by Western blotting with anti-phosphotyrosine antibody (anti-PY). A protein of 41 kDa (p41) consistently showed more intense reactivity to anti-PY than controls. Blots treated with anti-PY, stripped of the antibody, and reblotted with microtubule-associated protein kinase (MAPK, p42MAPK) antibody show only one band. The molecular mass of that band exactly matches that of p41. MAPK-reactive protein is present in control and stimulated cells, although the intensity of the band is greater in the latter. GM-CSF-stimulated phosphorylation of p41 is time- and dose-dependent. Anti-MAPK antibody detects a single band of 41 kDa, whose intensity increases with time of incubation and concentration of the agonist. Thus, the anti-MAPK antibody appears to react better to the phosphorylated form of p41 from GM-CSF-stimulated cells than to the dephosphorylated form. The p41 and MAPK proteins are localized in the cytosol. Finally, MAPK immunoprecipitates were probed with anti-PY in Western blots and a band of 41 kDa was found. In summary, these results suggest that this 41-kDa protein in neutrophils that is tyrosine phosphorylated in response to GM-CSF and other stimuli is MAPK. Its phosphorylation may represent an early and crucial signal associated with the GM-CSF neutrophil stimulation cascade.
...
PMID:Granulocyte-macrophage colony-stimulating factor-induced protein tyrosine phosphorylation of microtubule-associated protein kinase in human neutrophils. 132 42

Granulocyte-macrophage colony-stimulating factor (GM-CSF), Interleukin-3 (IL-3), and Steel Factor (SF) induce proliferation of hematopoietic cells through binding to specific, high-affinity, cell surface receptors. However, little is known about postreceptor signal transduction pathways. In previous studies, we noted that each of these three factors could independently support proliferation of the human MO7 cell line, and also that each factor induced a rapid increase in protein-tyrosyl phosphorylation. Although the proteins phosphorylated on tyrosine by GM-CSF and IL-3 are similar or identical in MO7 cells, many of the proteins that are phosphorylated on tyrosine after SF are different. However, two proteins, p42 and p44, were prominently phosphorylated in response to all three of the factors. In MO7 cells, the tyrosyl phosphorylation of p42 and p44 was transient, peaking at 5 to 15 minutes. In contrast to many of the other proteins which are tyrosyl phosphorylated in response to these factors, phosphorylation of p42 and p44 was temperature-dependent, occurring at 37 degrees C, but not at 4 degrees C. We identified the p42 protein as p42 Mitogen-Activated Protein Kinase (p42mapk, ERK-2) and the p44 as a p42mapk-related protein using monospecific antisera to MAP kinase. GM-CSF, IL-3, and SF were each found to induce MAP kinase activity when assayed in vitro using myelin basic protein (MBP) as a substrate. Remarkably, we found that GM-CSF-induced tyrosyl phosphorylation of p42 and p44 even in nonproliferative cells (neutrophils) that respond to this CSF, and that p42 and p44 were two of the most prominently tyrosyl phosphorylated proteins following GM-CSF stimulation of these cells. These results implicate p42mapk and p44 as important signal transducing molecules in myeloid cells, and it is likely that these kinases play a role as part of a sequential "kinase cascade" linking growth factor receptors to mitogenesis and other cellular responses.
...
PMID:Granulocyte-macrophage colony-stimulating factor, interleukin-3, and steel factor induce rapid tyrosine phosphorylation of p42 and p44 MAP kinase. 137 18

The addition of interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) to hormone-dependent cells induces tyrosine phosphorylation of Janus protein kinase 2 (Jak2) and activates its in vitro kinase activity. To explore the role of Jak2 in IL-3/GM-CSF-mediated signal transduction, we constructed a CD16/CD7/Jak2 (CD16/Jak2) fusion gene containing the external domain of CD16 and the entire Jak2 molecule and expressed this fusion protein using a recombinant vaccinia virus. The clustering of CD16/Jak2 fusion protein by cross-linking with an anti-CD16 antibody induced autophosphorylation of the fusion protein but did not induce the phosphorylation of either the endogenous Jak2 or the beta chain. Cross-linking of CD16/Jak2 stimulates the tyrosine phosphorylation of a large group of proteins that are also phosphorylated after the addition of IL-3 or GM-CSF and include proteins of 145, 97, 67, 52, and 42 kDa. Closer analysis demonstrated that the CD16/Jak2 phosphorylates Shc, a 52-kDa protein, and the 145-kDa protein associated tightly with Shc, as well as mitogen-associated protein kinase (pp42). Electrophoretic mobility shift assays demonstrate that CD16/Jak2 activates the ability of signal transduction and activation of transcription (STAT) proteins to bind to an interferon-gamma-activated sequence oligonucleotide in a manner similar to that seen after IL-3 treatment. Cross-linking of the CD16/Jak2 protein stimulated increases in c-fos and junB similar to IL-3 but did not cause major changes in the levels of the c-myc message, which normally increases after IL-3 treatment. Thus, a transmembrane CD16/Jak2 fusion is capable of activating protein phosphorylation and mRNA transcription in a manner similar but not identical to hematopoietic growth factors.
...
PMID:Signal transduction by a CD16/CD7/Jak2 fusion protein. 754 2

Stimulatory cytokines, including granulocyte-macrophage colony-stimulating factor (GM-CSF) and steel factor (SLF), act in a synergistic manner to stimulate the growth of hematopoietic progenitor cells, an effect also demonstrated for the growth factor-dependent human hematopoietic cell line MO7e. While little is known about the mechanisms responsible for mediating synergistic interactions of cytokines, Raf-1, a component of the MAP kinase signaling pathway, is thought to play a role in the stimulatory response evoked by several cytokines, including SLF and GM-CSF. Interferon-inducible protein-10 (IP-10) and macrophage inflammatory protein-1 alpha (MIP-1 alpha) are members of the chemokine family of suppressive cytokines. Prior exposure of hematopoietic cells to chemokines, including IP-10 and MIP-1 alpha, inhibits the synergistic action of growth factors on stimulating cell proliferation. We report that treatment of MO7e cells with the combination of GM-CSF and SLF directly stimulates statistically significant synergistic increases in the phosphorylation and activation of Raf-1 kinase, and in cellular protein synthesis levels. Pretreatment of MO7e cells with IP-10 or MIP-1 alpha blocked synergistic growth factor action, resulting in statistically significant suppression of cell proliferation, protein synthesis, and Raf-1 phosphorylation and activation. IP-10 and MIP-1 alpha treatment also evoked significant increases in intracellular cAMP levels. Pretreatment of cells with agents which serve to raise intracellular cAMP levels, or with cAMP analogs inhibited the synergistic actions of GM-CSF and SLF in a manner similar to IP-10 and MIP-1 alpha. In addition, treatment of cells with a potent inhibitor of cAMP-dependent protein kinase A blocked the suppressive action of MIP-1 alpha and IP-10 on Raf-1 kinase activity and on MO7e cell proliferation. The ability of IP-10 and MIP-1 alpha to antagonize the synergistic action of GM-CSF and SLF appears to involve inactivation of Raf-1 and the down-regulation of protein synthesis. Our findings suggest that both MIP-1 alpha and IP-10 mediate their suppressive effects in MO7e cells by stimulating increases in cellular cAMP levels and activating protein kinase A, a mechanism we believe to be unique to these chemokines and not one applied to all growth suppressive members of the chemokine superfamily (for example, interleukin 8 and platelet factor 4).
...
PMID:Interferon-inducible protein 10 and macrophage inflammatory protein-1 alpha inhibit growth factor stimulation of Raf-1 kinase activity and protein synthesis in a human growth factor-dependent hematopoietic cell line. 1660 26

Human polymorphonuclear neutrophils exhibit a low level of the microtubule-associated protein kinase (MAPK) activity. This enzymic activity is enhanced up to 3-fold upon cell stimulation with the human haematopoietic hormone granulocyte-macrophage colony-stimulating factor (GM-CSF). This is demonstrated both in whole-cell lysates and in DEAE-anion-exchange semi-purified fractions prepared from GM-CSF-stimulated neutrophils, by assaying the kinase activity against either myelin basic protein or a phosphoacceptor peptide that bears the specific phosphorylation site of the MAPK natural substrate. Similarly, phosphorylation of MAPK in tyrosine residues, as found in immunoblots using anti-phosphotyrosine antibodies, follows similar time- and dose-response curves as the kinase activation. Pretreatment of the cells with the tyrosine kinase inhibitor genistein abrogates the above-mentioned effect, whereas the phosphatase inhibitor okadaic acid enhances both the basal and the GM-CSF-stimulated kinase activities. Likewise, MAPK tyrosine phosphorylation is diminished in genistein-treated neutrophils, and enhanced in okadaic acid-treated cells. We conclude that MAPK activity is present in human neutrophils, and that it is stimulated by GM-CSF. This stimulation of the activity is most likely due to the phosphorylation of MAPK in tyrosine residues triggered upon binding of GM-CSF to its receptors.
...
PMID:Direct stimulation by tyrosine phosphorylation of microtubule-associated protein (MAP) kinase activity by granulocyte-macrophage colony-stimulating factor in human neutrophils. 768 11

The present study was undertaken to determine the identities and characteristics of proteins with molecular masses between 40 and 44 kDa whose tyrosine phosphorylation increases in human neutrophils following stimulation of these cells with tumour necrosis factor alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Immunoblotting results demonstrate that addition of GM-CSF to human neutrophils increases the tyrosine phosphorylation of two proteins with molecular masses of 42 and 44 kDa. However, the addition of TNF-alpha to neutrophils induces a time- and dose-dependent increase in tyrosine phosphorylation of a 40 kDa protein. Immunoprecipitation using specific mitogen-activated protein kinase (MAPK) isoform antibodies and an antibody which recognizes phosphotyrosine-containing proteins demonstrated that the 42 and 44 kDa proteins are isoforms of MAPKs. Utilizing an in situ gel kinase activity assay, GM-CSF increases the kinase activity of the 42 and 44 kDa proteins. Moreover, using immunoprecipitated p42 and p44 MAPK isoforms in this gel assay revealed activity associated with the p42 and p44 MAPK isoforms. Using the same in situ assay, TNF-alpha induces an increase in kinase activity of a 40-42 kDa protein. However, the 40 kDa protein whose phosphorylation on tyrosine residues increased in human neutrophils following stimulation with TNF-alpha is not a member of the known MAPK family, demonstrating the divergences in pathways utilized by GM-CSF and TNF-alpha. This 40 kDa protein may be related to the recently identified protein that becomes phosphorylated on tyrosine residues upon stimulation of the human epidermal carcinoma cell line KB by interleukin-1. In these cells the p40 protein is part of a protein kinase cascade which results in the phosphorylation of the small heat shock protein, hsp27.
...
PMID:Effects of granulocyte-macrophage colony-stimulating factor and tumour necrosis factor-alpha on tyrosine phosphorylation and activation of mitogen-activated protein kinases in human neutrophils. 771 91

Adherence of human neutrophils to plastic, fibronectin, or collagen-coated surfaces modifies their response to several agonists including granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor alpha (TNF-alpha), and fMet-Leu-Phe, permitting them to trigger superoxide anion (O2-) release, which they are unable to do as cells in suspension. Adherence of neutrophils causes a slight decrease in the basal level of tyrosine phosphorylation compared with that of suspended cells. The addition of GM-CSF, however, brings all proteins to a level of phosphorylation at least equal to that seen in suspended cells. In the case of a 130-kDa (p130) and a 42-kDa (p42) protein, the increase in tyrosyl phosphorylation in response to GM-CSF challenge is clearly larger in adherent than in suspended cells (6- and 4-fold increases for p130 and p42, respectively, in adherent cells vs. 1.7- and 2.1-fold in suspended cells). This is even more patient in the case of collagen-coated plates (9.4-fold increase for p42). Therefore, once neutrophils attach to surfaces, they become primed and respond to GM-CSF with greater potency than when they are in suspension. By Western blot analysis with anti-MAP kinase antibodies, we demonstrate that p42 is one member of the mitogen-activating protein kinase, namely the p42MAPK. The tyrosyl phosphorylation of p42MAPK is elevated in GM-CSF-treated adherent neutrophils in a time-dependent fashion as measured by the formation of a doublet composed of the phospho (or activated) form and the dephospho (or inactive) form of MAP kinase. MAP kinase activation and tyrosine phosphorylation are inhibited by tyrosine kinase inhibitors genistein and tyrphostin-23. Our results indicate that adherence acts to prime neutrophils for enhanced functionality and that tyrosine phosphorylation is involved in this process.
...
PMID:Priming of tyrosine phosphorylation in GM-CSF-stimulated adherent neutrophils. 772 26

Deletion analysis of the beta subunit of the human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor previously defined two cytoplasmic regions required for distinct signaling. The membrane-proximal region is responsible for induction of c-myc and pim-1, and is indispensable for GM-CSF-dependent proliferation of mouse BaF3 transfectants. The distal region is required for activation of Ras, Raf-1, MAP kinase and p70 S6 kinase as well as induction of c-fos and c-jun, but is dispensable for GM-CSF-dependent proliferation of transfectants under normal culture conditions containing serum. Here we show that signals induced by the distal region of the beta subunit are also required for proliferation. GM-CSF supported proliferation of BaF3 transfectants expressing the normal beta subunit, even in serum-free medium. However, in the absence of seru, GM-CSF did not support proliferation of BaF3 transfectants that have the beta deletion mutants lacking the distal region. Serum-induced activation of Ras, phosphorylation of MAP kinase and expression of c-fos in parental BaF3 cells and antisense oligonucleotide against c-raf blocked DNA synthesis of BaF3 cells. These results indicate that proliferation of BaF3 cells requires signals induced by the proximal as well as the distal region of the beta subunit of the GM-CSF receptor, and that serum alleviates the requirement of signals induced by the distal region.
...
PMID:Serum alleviates the requirement of the granulocyte-macrophage colony-stimulating factor (GM-CSF)-induced Ras activation for proliferation of BaF3 cells. 792 37

The high-affinity receptor for granulocyte-macrophage colony-stimulating factor (GM-CSF) consists of a unique alpha chain and a beta c subunit that is shared with the receptors for interleukin-3 (IL-3) and IL-5. Two regions of the beta c chain have been defined; these include a membrane-proximal region of the cytoplasmic domain that is required for mitogenesis and a membrane-distal region that is required for activation of Ras, Raf-1, mitogen-activated protein kinase, and S6 kinase. Recent studies have implicated the cytoplasmic protein tyrosine kinase JAK2 in signalling through a number of the cytokine receptors, including the IL-3 and erythropoietin receptors. In the studies described here, we demonstrate that GM-CSF stimulation of cells induces the tyrosine phosphorylation of JAK2 and activates its in vitro kinase activity. Mutational analysis of the beta c chain demonstrates that only the membrane-proximal 62 amino acids of the cytosolic domain are required for JAK2 activation. Thus, JAK2 activation is correlated with induction of mitogenesis but does not, alone, activate the Ras pathway. Carboxyl truncations of the alpha chain, which inactivate the receptor for mitogenesis, are unable to mediate GM-CSF-induced JAK2 activation. Using baculovirus-expressed proteins, we further demonstrate that JAK2 physically associates with the beta c chain but not with the alpha chain. Together, the results further support the hypothesis that the JAK family of kinase are critical to coupling cytokine binding to tyrosine phosphorylation and ultimately mitogenesis.
...
PMID:JAK2 associates with the beta c chain of the receptor for granulocyte-macrophage colony-stimulating factor, and its activation requires the membrane-proximal region. 800 42

Interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have previously been reported to induce rapid phosphorylation of the mitogen-activated protein (MAP) kinase. However, little is known about signaling events initiated by both hematopoietins that occur downstream of the MAP kinase. MAP kinase has been shown to phosphorylate the AP-1 transcription factor and also to activate two kinases designated insulin-stimulated protein kinase-1 and MAP kinase-activated protein (MAP-KAP) kinase 2. We show here that IL-3 and GM-CSF induce MAPKAP kinase 2 activity in the human megakaryoblastic leukemia cell line MO7 and phosphorylate the human small heat shock protein Hsp 27 on serine residues in vitro. GM-CSF also induced Hsp 27 phosphorylation in neutrophils in a range similar to that observed in MO7 cells, suggesting that MAPKAP kinase 2-mediated Hsp 27 activation occurs independently of proliferation. Hsp 27 phosphorylation was dose-dependent, occurred as early as 5 minutes after factor exposure, and was inhibited by the tyrosine kinase inhibitors genistein and herbimycin A. Furthermore, the protein phosphatase A2 abolished IL-3- and GM-CSF-induced serine phosphorylation of Hsp 27. Taken together, our findings indicate that tyrosine phosphorylation of MAP kinase is a prerequisite for serine phosphorylation of Hsp 27, which is mediated by MAPKAP kinase 2. Hsp 27 has shown activation-dependent translocation from the cytosolic to the nuclear region and has been linked to the cellular stress response. However, its precise function is largely unknown. Our data identify Hsp 27 as a target of the IL-3/GM-CSF stimulation pathway that involves MAP kinase and MAPKAP kinase 2. In addition, our results indicate that Hsp 27 may be target of phosphorylation events not only in the stress response but also in unstressed cells responding to cytokine stimulation.
...
PMID:Interleukin-3 and granulocyte-macrophage colony-stimulating factor induce activation of the MAPKAP kinase 2 resulting in in vitro serine phosphorylation of the small heat shock protein (Hsp 27). 1101 49

1 2 3 4 5 6 7 8 9 10 Next >>