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

Receptors for the hematopoietic growth factors erythropoietin, interleukin 3 (IL-3), and granulocyte-macrophage colony-stimulating factor (GM-CSF) are members of a structurally related receptor superfamily. Interestingly, while none of these receptors encode tyrosine kinase activities, induced tyrosine phosphorylation has been observed in various responsive cells stimulated with each factor. Toward defining possible common transduction pathways which are activated by these three cytokines, we have studied induced protein phosphorylation in murine myeloid FDC-P1 cells stably transfected with an erythropoietin receptor cDNA (FDC-ER cells). FDC-ER cells proliferate in response to erythropoietin (Quelle, D. E., and Wojchowski, D. M. (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 4801-4805), and presently are shown to rapidly phosphorylate a M(r) 100,000 cytosolic protein (pp100) at tyrosine residues in response to this factor. Phosphorylation of pp100 also is induced in FDC-P1 and FDC-ER cells in response to IL-3 or GM-CSF. Importantly, quantitative analyses showed identical concentration dependencies for factor-induced pp100 phosphorylation and induced cell proliferation. Moreover, a selective loss of proliferative responsiveness to GM-CSF in FDC-ER cells was associated with a reduced capacity of GM-CSF to induce pp100 phosphorylation. Finally, limited differences in tryptic phosphopeptide maps of pp100 as isolated following exposure to erythropoietin, IL-3, or GM-CSF were observed, suggesting that these factors also may preferentially induce phosphorylation of pp100 at distinct sites. These findings are consistent with a role for pp100 as a common cytosolic transducer in the apparently convergent pathways of erythropoietin-, IL-3-, and GM-CSF-induced proliferation of myeloid progenitor cells.
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PMID:Interleukin 3, granulocyte-macrophage colony-stimulating factor, and transfected erythropoietin receptors mediate tyrosine phosphorylation of a common cytosolic protein (pp100) in FDC-ER cells. 132 20

The "stromal" or adherent cells of long-term murine Dexter explant bone marrow cultures provide the best in vitro model of the bone marrow microenvironment. Colony-stimulating factor-1 (CSF-1) is produced constitutively by these cells and is easily detected, but most investigators have not found constitutive production of the other hemolymphopoietic cytokines. We have previously reported the detection of granulocyte-macrophage-CSF (GM-CSF) in murine stromal cultures and its induction by the lectin Pokeweed mitogen. The present studies analyzing stromal cytokine messenger RNA (mRNA) production by standard Northern blot analysis show constitutive production of mRNAs for CSF-1, GM-CSF, granulocyte-CSF (G-CSF), c-kit ligand (KL), and interleukin-6 (IL-6), but not IL-3, IL-4, or IL-5 by 3-week irradiated or nonirradiated murine Dexter stromal cells. Exposure of stromal cells to Pokeweed mitogen or IL-1 16 hours before RNA harvest induces the messages for GM-CSF, G-CSF, KL, and IL-6, but not IL-3, IL-4, IL-5, or CSF-1. Polymerase chain reaction amplification of cDNA made with reverse transcriptase from stromal RNA using two separate sets of IL-3-specific primers shows the presence of IL-3 message in irradiated stromal cells, which is only detectable with this more sensitive technique. The factor-dependent cell lines FDC-P1 and 32D are supported by the stromal cells without the addition of exogenous growth factors, demonstrating a cytokine activity in these cultures that is inhibited by the addition of anti-IL-3 or anti-GM-CSF antibodies. These data indicate that murine Dexter stromal cells constitutively produce CSF-1, GM-CSF, G-CSF, IL-6, KL, and IL-3. This growth factor production could explain the support of granulocyte, macrophage, and megakaryocyte production and stem cell maintenance in Dexter-type long-term murine bone marrow cultures.
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PMID:Biologic significance of constitutive and subliminal growth factor production by bone marrow stroma. 137 43

Gamma irradiation of plateau-phase clonal bone marrow stromal cell lines produces factor-independent growth of cocultivated clonal interleukin-3/granulocyte-macrophage colony-stimulating factor-dependent hematopoietic progenitor cell lines. The process is associated with three biologic changes including: (i) adherence of hematopoietic cells to stromal cells forming 'cobblestone islands'; (ii) an intermediate stage [during which the cells show proliferation in suspension in the presence in leukemogenic stromal factor (LSF), a factor similar to macrophage colony-stimulating factor (M-CSF) released by irradiated stromal cells, and transient hematopoietic cell surface expression of MAC-1, and c-fms (M-CSF receptor)]; and (iii) a third stage of factor-independence. A monoclonal antibody to M-CSF receptor inhibited proliferation of intermediate stage but not all factor-independent cell subclones. In the present studies, a subclonal factor-independent malignant subline of FDC-P1JL26 derived by cocultivation with gamma-irradiated stromal cells as well as the parent clone and intermediate stage cells were shown to express significant levels of M-CSF polyA+ mRNA and M-CSF of at least two sizes (23 and 15 kDa) as detected by 35S-methionine labelling and immunoprecipitation with polyclonal anti-M-CSF antiserum. There was no significant difference in intracellular M-CSF protein size between cells at each of the three stages of biologic change. This M-CSF was not detected on the cell surface by fluorescence-activated cell sorting (FACS). In contrast, c-fms expression at the cell surface was detected by FACS analysis and c-fms polyA+ mRNA was only detected during the intermediate stage of induction of factor-independence. FDC-P1JL26 parent cells, the subclone stimulated by LSF, and the factor-independent subclone, showed little or no detectable autophosphorylation of the c-fms receptor at tyrosine. There was no detectable rearrangement of the M-CSF or c-fms genes by Southern analysis between clonal lines during the three stages. While we cannot rule out an autocrine mechanism or mutated c-fms receptor mechanism, the data also suggest that evolution of hemopoietic cell factor-independence during cocultivation with irradiated stromal cells may involve a mechanism distal to the c-fms receptor/M-CSF interaction.
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PMID:Expression of M-CSF and its receptor (C-FMS) during factor-independent cell line evolution from hematopoietic progenitor cells cocultivated with gamma irradiated marrow stromal cell lines. 138 39

The receptors for interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) consist of two polypeptides each belonging to a new class of molecules referred to as the hemopoietin receptor family. When expressed alone, receptor polypeptides of this family often bind their respective factors with lower affinity than the receptors identified in whole cells. Despite the lack of structural evidence for any enzymatic activity of the receptor polypeptides, both IL-3 and GM-CSF stimulate tyrosine phosphorylation of multiple intracellular substrates. We investigated IL-3 and GM-CSF receptor structure and signaling in a myeloid cell line, FDC-P1, which is dependent on either IL-3 or GM-CSF for growth. Antiphosphotyrosine antibodies were used to immunoprecipitate tyrosine-phosphorylated proteins from 32P-labeled cells or to probe immunoblots. Both IL-3 and GM-CSF stimulated the phosphorylation of a similar pattern of polypeptides on tyrosine. One tyrosine phosphorylated polypeptide migrated with M(r) = 135,000 and increased to 150,000 over a period of 10 min following stimulation of cells with IL-3 or GM-CSF. The M(r) = 135,000-150,000 polypeptide phosphorylated in response to IL-3 was shown to be primarily the Aic-2A polypeptide, the low affinity IL-3 receptor. Phosphatase treatment showed that the dramatic IL-3-induced shift in apparent molecular weight from M(r) = 125,000 in unstimulated cells was entirely due to phosphorylation. The closely related receptor, Aic-2B, was also tyrosine phosphorylated in response to IL-3, although to a lesser extent than Aic-2A. Treatment with GM-CSF resulted in tyrosine phosphorylation of the Aic-2B polypeptide exclusively. It was intriguing that GM-CSF treatment did affect the mobility of the Aic-2A polypeptide on polyacrylamide gels. Together, these results suggest that the Aic-2A polypeptide is part of the IL-3 receptor complex, but not the GM-CSF receptor. In contrast, the Aic-2B polypeptide is a component of the GM-CSF receptor, but it can also be utilized in an IL-3 receptor.
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PMID:Tyrosine phosphorylation of receptor beta subunits and common substrates in response to interleukin-3 and granulocyte-macrophage colony-stimulating factor. 140 Apr 95

Gamma-irradiation of plateau phase cultures of the clonal murine bone marrow stromal cell line D2XRII followed by cocultivation of a clonal interleukin 3 (IL-3) (granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent hematopoietic progenitor cell line FDC-P1JL26 results in a significant increase in "cobblestone islands" of attachment and emergence of subclonal factor-independent malignant sublines. Biochemical purification of conditioned medium from irradiated D2XRII cells yielded a 75,000-dalton glycoprotein termed leukemogenic stromal factor (LSF) that was neutralized by a polyclonal antiserum to murine macrophage colony-stimulating factor (M-CSF). A monoclonal antibody to the murine M-CSF receptor (c-fms) neutralized the biological activity of this molecule in a manner comparable to its effect on recombinant human or murine M-CSF. FDC-P1JL26 parent cells were positive for Ly5, MEL-14, mGR, VLA-4, PGP-1 (CD44), and Thy1.2. After culture in LSF, Thy1.2, MEL-14, and mGR became undetectable; however, significant cell surface MAC-1 antigen and c-fms (M-CSF receptor) were expressed. Neither line was positive for Ly6, Ly22, I-CAM-1, or B220 antigen. LSF-precultured FDC-P1JL26 cells transferred as single cells to microwell culture with 5000-cGy-irradiated D2XRII cells revealed a 60-fold increase in frequency of cobblestone island formation and evolution of factor-independent subclones compared to the parent line. Both parent and LSF-precultured cells became factor independent at a 100-fold lower frequency if kept in suspension in LSF in the absence of stromal cells. Antiserum to M-CSF or monoclonal antibody to the murine M-CSF receptor (c-fms) did not inhibit or displace cobblestone island formation by either clone of FDC-P1 on irradiated stromal cells indicating a mechanism of binding not involving the M-CSF receptor. However, anti-serum to the M-CSF receptor inhibited growth of one factor-independent subclone. In separate studies, a subclone of IL-3-dependent 32Dc13 cells, expressing the transfected murine c-fms protooncogene but not the parent 32Dc13 cell line or another subclone expressing the transfected gene for the human M-CSF receptor, showed adherence and became factor independent when cocultivated with irradiated D2XRII stromal cells. Thus, irradiated stromal cells bind M-CSF receptor-positive hematopoietic progenitor cells and induce c-fms-dependent factor-independent tumorigenic subclones. The cellular interactions in this model may be relevant to gamma-irradiation leukemogenesis in vivo.
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PMID:Humoral and cell surface interactions during gamma-irradiation leukemogenesis in vitro. 153 94

Murine receptors for granulocyte-macrophage colony-stimulating factor (GM-CSF) and Multi-CSF (interleukin-3) can exist in both high- and low-affinity forms and demonstrate trans-modulation by several different ligands. In contrast the recently cloned human GM-CSF receptor and murine interleukin-3 (IL-3) receptor display only low-affinity binding. To begin to understand the molecular basis of the formation of high- and low-affinity receptors and their trans-modulation we have developed methods for the solubilization and assay of GM-CSF and interleukin-3 receptors so that their binding characteristics can be studied in cell-free solution. Both receptors displayed a single class of high-affinity binding on intact FDC-P1 cells and IL-3 receptors had unaltered binding characteristics in cells, membranes and in detergent solution. However, GM-CSF receptors were converted to a single class of low-affinity binding in detergent solution while both high- and low-affinity forms were evident in membranes. The basis of affinity conversion of GM-CSF receptors was exclusively a change in the kinetic dissociation rate of ligand. Cross-linking experiments suggested that high-affinity receptors for GM-CSF and IL-3 might consist of two different protein species and, if this is so, the data suggest that this association is more stable for IL-3 than for GM-CSF receptors.
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PMID:Affinity conversion of receptors for colony stimulating factors: properties of solubilized receptors. 153 15

Interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor induce the rapid phosphorylation of the c-raf protein in the growth factor-dependent FDC-P1 and DA-3 murine myeloid cell lines. Furthermore, immunoprecipitates of c-raf isolated from growth factor-stimulated cells demonstrate a marked increase in intrinsic protein kinase activity as measured in vitro. IL-3 and granulocyte-macrophage colony-stimulating factor induce phosphorylation of c-raf at both serine and tyrosine residues. Antiphosphotyrosine immunoprecipitates from IL-3-stimulated cells demonstrate the rapid and coordinate phosphorylation of both c-raf and a protein co-migrating with the 140-kDa putative IL-3 receptor component. Collectively, the findings of rapid and coordinate ligand-induced phosphorylation of a potential IL-3 growth factor receptor component and cytoplasmic c-raf with concomitant c-raf activation provide a cogent sequential molecular model for linking external growth stimuli to intracellular signal transduction events.
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PMID:Interleukin-3 and granulocyte-macrophage colony-stimulating factor mediate rapid phosphorylation and activation of cytosolic c-raf. 170 Sep 80

Erythrocyte development in mammals depends in part upon the interaction of the glycopeptide hormone erythropoietin (EPO) with cell surface receptors on committed erythroid progenitor cells. Both this factor and an EPO receptor polypeptide previously have been cloned, yet little is presently understood concerning molecular mechanisms of receptor activation and signal transduction. To identify cytosolic receptor domains necessary for signaling, we have compared the activities of a series of deletionally mutated EPO receptor constructs by their expression in interleukin 3-dependent, myeloid FDC-P1 cells. EPO-induced growth was transduced efficiently in these cells by the full-length receptor (507 amino acids), and no measurable loss in activity resulted from the deletion of up to 111 carboxyl-terminal residues. In contrast, the deletion of 44 additional residues led to a dramatic loss (86.3% +/- 7.8%; mean +/- SD) in the ability of this receptor to mediate EPO-induced growth, thus indicating that residues between Gly-352 and Met-396 constitute a functionally critical cytosolic subdomain. Interestingly, the expression of full-length EPO receptors in FDC-P1 cells also led to a selective inhibition of normal proliferative responsiveness to the alternative hematopoietic factor granulocyte-macrophage colony-stimulating factor. Moreover, this inhibition was progressively reversed in forms of the EPO receptor in which distal cytosolic residues were sequentially deleted. These results suggest that EPO receptors normally may trans-modulate components in the pathway of granulocyte-macrophage colony-stimulating factor-induced proliferation and that this down-modulation, as exerted by intact EPO receptors, may play a role in promoting erythroid commitment during myeloid blood cell development.
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PMID:Localized cytosolic domains of the erythropoietin receptor regulate growth signaling and down-modulate responsiveness to granulocyte-macrophage colony-stimulating factor. 171 Dec 11

Erythropoietin mediates the rapid phosphorylation of Raf-1 in the murine cell lines HCD-57 and FDC-P1/ER, which proliferate in response to this cytokine. Phosphorylation occurs at both serine and tyrosine residues and as such is similar to the Raf-1 phosphorylation seen after interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor, and interleukin-2 stimulation in other murine cell lines. Such data suggest that these growth factors may share a common mechanism(s) of Raf-1 phosphorylation. Furthermore, in association with Raf-1 phosphorylation, erythropoietin induces a 2-3-fold increase in Raf-1 kinase activity as measured in immune complex kinase assays in vitro. Finally, a c-raf antisense oligodeoxyribonucleotide, which specifically decreases intracellular Raf-1 levels, also substantially inhibits both erythropoietin and IL-3-directed DNA synthesis. Together, these results provide evidence that activated Raf-1 is a necessary component of erythropoietin and IL-3 growth signaling pathways.
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PMID:Erythropoietin induces Raf-1 activation and Raf-1 is required for erythropoietin-mediated proliferation. 186 34

Colony-stimulating factor-1 (CSF-1 or M-CSF) supports the proliferation and survival of mononuclear phagocytes by binding to a receptor (CSF-1R) encoded by the c-fms proto-oncogene. Whereas the CSF-1R kinase is normally regulated by ligand, receptors bearing 'activating mutations' act constitutively as enzymes and can transform fibroblasts and haemopoietic cells of different lineages. Introduction of human CSF-1R enables mouse NIH-3T3 cells to form colonies in agar in response to human CSF-1 and to proliferate in serum-free medium supplemented with CSF-1, albumin, transferrin and insulin. Similarly, expression of human CSF-1R in interleukin 3-dependent mouse FDC-P1 myeloid cells enables them to grow in CSF-1. High levels of CSF-1R expression in FDC-P1 cells can induce factor-independent growth which is abrogated by a 'neutralizing' monoclonal antibody to the receptor. Therefore, critical mutations in the c-fms gene or overexpression of CSF-1R in immature myeloid precursors might each contribute to leukaemia.
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PMID:Signal-response coupling mediated by the transduced colony-stimulating factor-1 receptor and its oncogenic fms variants in naive cells. 215 60


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