Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.5 (RNase)
 17,967 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The murine myeloid precursor cell line FDC-P1/MAC simultaneously expresses receptors for multi-colony-stimulating factor (CSF), granulocyte-macrophage (GM)-CSF, and macrophage (M)-CSF. Growth of FDC-P1/MAC cells in either multi-CSF or GM-CSF results in the posttranscriptional suppression of M-CSF receptor (c-fms proto-oncogene) expression. We use the term transregulation to describe this control of receptor expression and have further characterized this regulatory process. The removal of FDC-P1/MAC cells from GM-CSF stimulation resulted in the re-expression of c-fms mRNA independent of M-CSF stimulation and new protein synthesis. Switching FDC-P1/MAC cells from growth in M-CSF to GM-CSF caused the selective degradation of c-fms mRNA within 6 h after factor switching. Blocking protein synthesis or gene transcription with metabolic inhibitors effectively prevented GM-CSF stimulated degradation of c-fms mRNA. These results suggest that the transregulation of c-fms transcripts by GM-CSF requires the transcriptional activation of a selective mRNA degradation factor. In vitro analysis, the use of cytoplasmic cell extracts, provided evidence that a ribonuclease is preferentially active in GM-CSF stimulated cells, although the specificity for mRNA degradation in vitro is broader than seen in vivo. Together, these data suggest that GM-CSF can dominantly transregulate the level of c-fms transcript through the transcriptional activation of a ribonuclease degradation system.
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PMID:A GM-colony-stimulating factor (CSF) activated ribonuclease system transregulates M-CSF receptor expression in the murine FDC-P1/MAC myeloid cell line. 153 42

Recent studies have demonstrated by Northern blot analysis that both the c-fms proto-oncogene and the CSF-1 gene are expressed during human monocytic differentiation. In order to examine c-fms and CSF-1 expression at the cellular level, we have applied alkaline phosphatase detection of biotinylated v-fms and CSF-1 cDNA probes in situ. Using this approach, we demonstrate that c-fms and CSF-1 transcripts are detectable in HL 60 cells induced along the monocytic lineage but not in uninduced cells. The specific detection of these transcripts is further supported by the absence of histochemical staining in RNase-treated cells and when using pBR322 plasmid without insert as the biotinylated probe. Finally, the results indicate that most of the induced HL-60 cells have detectable levels of both c-fms and CSF-1 RNA. This approach should be useful for studying expression of these genes in populations of leukemic blasts and normal hematopoietic cells.
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PMID:Detection of c-fms and CSF-1 RNA by in situ hybridization. 244 33

The gene encoding the receptor for macrophage colony-stimulating factor 1 (CSF-1), the c-fms protooncogene, is selectively expressed in immature and mature mononuclear phagocytes and trophoblasts. Exon 1 is expressed only in trophoblasts. Isolation and sequencing of genomic DNA flanking exon 2 of the murine c-fms gene revealed a TATA-less promoter with significant homology to human c-fms. Reverse transcriptase primer extension analysis using exon 2 primers identified multiple clustered transcription initiation sites. Their position was confirmed by RNase protection. The same primer extension products were detected in equal abundance from macrophage or nonmacrophage sources of RNA. c-fms mRNA is acutely down-regulated in primary macrophages by CSF-1, bacterial lipopolysaccharide (LPS), and phorbol myristate acetate (PMA). Each of these agents reduced the abundance of c-fms RNA detectable by primer extension using an exon 3 primer without altering the abundance of presumptive short c-fms transcripts detected with exon 2 primers. Primer extension analysis with an intron 2 primer detected products at greater abundance in nonmacrophages. Templates detected with the intronic primer were induced in macrophages by LPS, PMA, and CSF-1, suggesting that each of the agents caused a shift from full-length c-fms mRNA production to production of unspliced, truncated transcripts. The c-fms promoter functioned constitutively in the RAW264 macrophage cell line, the B-cell line MOPC.31C, and several nonhematopoietic cell lines. Macrophage-specific expression and responsiveness to selective repression by LPS and PMA was achieved by the incorporation of intron 2 into the c-fms promoter-reporter construct. The results suggest that expression of the c-fms gene in macrophages is controlled by sequences in intron 2 that act by regulating transcription elongation.
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PMID:Expression of mRNA encoding the macrophage colony-stimulating factor receptor (c-fms) is controlled by a constitutive promoter and tissue-specific transcription elongation. 849 48

The human granulocyte-macrophage colony-stimulating factor receptor (GM-CSFR) alpha chain RNA is alternatively spliced to yield receptor isoforms. Two of these, alpha 1 and alpha 2, differ in their cytoplasmic domains. Because the GM-CSFR beta chain (beta c) is shared with the receptors for interleukins 3 and 5 it is possible that the alpha chain confers specificity on the GM-CSF response and that the different isoforms might refine this response further. Studies have been directed at determination of the respective biological roles of the alpha 1 and alpha 2 isoforms. Expression of the isoforms was examined by RNase protection analysis in normal granulocytes and a variety of cell lines of haemopoietic origin, at different stages of differentiation and activation. Expression was also analysed in cells from patients with a variety of leukaemic subtypes. Results demonstrated that the relative abundance of the isoforms was similar in all cell populations examined. The human GM-CSFR alpha 1 or alpha 2 receptors were independently expressed in the murine factor-dependent cell line FDC-P1, so that the properties of the receptors could be compared. Cell lines that expressed either receptor could be converted to growth in response to human GM-CSF and assumed a more differentiated phenotype when compared with the parental cell line. However, the morphology, expression of cell surface antigens and dose-growth response characteristics did not differ significantly between cells that expressed either the alpha 1 or alpha 2 receptor. These studies demonstrate that the alpha 1 and alpha 2 subunits of the GM-CSF receptor are co-ordinately regulated in both normal and malignant haemopoiesis. Furthermore, each receptor is able to deliver both proliferative and differentiative signals to myeloid cells.
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PMID:Expression and functional analysis of two isoforms of the human GM-CSF receptor alpha chain in myeloid development and leukaemia. 933 6

A number of cytokines and their receptors are abundantly expressed at the materno-fetal interface and are thought to have a function in the regulation of placentation. Granulocyte-colony stimulating factor (G-CSF) is expressed by stromal cells in both placental tissue and maternal decidua throughout placentation. In this study, we examined the expression of placental G-CSF receptor (G-CSFR) mRNA and protein throughout gestation by ribonuclease protection assays, Western blotting, and immunohistochemistry. The major placental form of G-CSFR mRNA, corresponding to a membrane-bound form of the protein, was present in first-trimester placental tissues; levels decreased in second- and were highest in third-trimester placental tissues. Two placental G-CSFR molecules, 120 kDa and 150 kDa, were detected in first- and third-, but not second-, trimester tissues. The level of the 150-kDa G-CSFR was greater in the third- than in first-trimester samples. These differences were irrespective of whether or not the patients had received prostaglandin E1 analogues, prostaglandin E1 analogues and oxytocin, oxytocin alone, or mifepristone before labor. We demonstrated by immunohistochemistry that interstitial cytotrophoblast in first- and second-trimester decidual tissue and cytotrophoblast in term fetal membranes express G-CSFR. These data demonstrate that the expression of specific forms of placental G-CSFR is strictly cell type- and developmental stage-specific, and they suggest that G-CSFR may be important in decidual invasion of cytotrophoblast and in trophoblast function during placentation.
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PMID:Gestational regulation of granulocyte-colony stimulating factor receptor expression in the human placenta. 1008 50

CSF-1 plays an important role in female reproduction and normal embryo development. To understand further CSF-1 function in normal and, especially, in compromised pregnancy, we studied the pattern of its mRNA expression as well as expression of its receptor (c-fms) in the uteroplacental units of mice with induced (cyclophosphamide (CY)-treated) and spontaneous (CBA/J x DBA/2J mating combination) pregnancy loss. RNase protection analysis demonstrated the presence of two forms of CSF-1 mRNA in the uteroplacental unit corresponding to 1400- and 263-bp protective fragments. Densitometric analysis demonstrated that the level of 1400-bp mRNA form was decreased by 40% in the uteroplacental units of mice with CY-induced pregnancy loss compared with the control mice. About 20% decrease in 263-bp protective fragment was registered in resorbing versus non-resorbed placenta of CBA/J females mated to DBA/2J males. As judged by in situ hybridization assay, CSF-1 mRNA transcripts were localized in the uterine epithelium and stroma, while c-fms mRNA was found mainly in the trophoblast. The number of metrial gland cells as well as the number of uterine leucocytes expressing CSF-1 and c-fms mRNAs was substantially lower in the uteroplacental unit of mice with pregnancy loss than in control animals. Maternal immunostimulation, while significantly decreasing the resorption rate in mice with CY-induced pregnancy loss, also strengthened CSF-1 mRNA expression at the fetomaternal interface and resulted in reconstitution in the number of CSF-1+ uterine leucocytes and metrial gland cells. These data suggest a role for uterine CSF-1 in the physiology of normal and compromised pregnancy and demonstrate a possible involvement of CSF-1-associated signalling in mechanisms of placenta and endometrium repair following immunopotentiation.
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PMID:Colony-stimulating factor-1 (CSF-1) expression in the uteroplacental unit of mice with spontaneous and induced pregnancy loss. 1046 60

The osteopetrotic (op/op) mouse, deficient in biologically active colony stimulating factor 1 (CSF-1), was used to examine the role of microglia in chemical-induced trauma. Op/op mice and normal phenotype littermates (non-op/op) received an acute i.p. injection of the hippocampal toxicant, trimethyltin hydroxide (TMT; 1.5 or 2.0 mg/kg). At 2.0 mg/kg, both mice displayed severe degeneration of dentate granule neurons. At 1.5 mg/kg, non-op/op mice showed a limited punctate pattern of neuronal death while op/op mice showed prominent neuronal death. TMT-induced astrocyte reactivity was similar in both groups. RNase protection assays were conducted on hippocampal tissue at 24 hr post-TMT. Elevations were seen in mRNA levels for the host response genes: intercellular cell adhesion molecule (ICAM-1; non-op/op 80%, op/op 85%), the protease inhibitor EB22 (non-op/op 60%, op/op 300%), and glial fibrillary acidic protein (GFAP; non-op/op 300%, op/op 480%) within 24 hr. Macrophage-1 antigen (Mac-1) mRNA levels were lower in all op/op mice and were not induced by TMT exposure. Macrophage inflammatory protein (MIP)-1alpha and MIP-1beta mRNA levels were elevated in non-op/op mice while mRNA levels for interferon inducible protein (IP-10) and monocyte chemoattractant protein (MCP-1) were elevated in op/op mice. Tumor necrosis factor alpha (TNFalpha) mRNA levels were significantly elevated in both non-op/op (100%) and op/op (600%) mice. TNFbeta mRNA levels in op/op mice were elevated 200% and interleukin 1alpha (IL-1alpha) 150%. Reverse transcriptase polymerase chain reaction (RT-PCR) showed a TMT-induced elevation in INFalpha and INFbeta mRNA levels and no elevation of INFgamma. mRNA levels of the CSF-1 receptor, c-fms, were unaltered.
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PMID:Chemical-induced hippocampal neurodegeneration and elevations in TNFalpha, TNFbeta, IL-1alpha, IP-10, and MCP-1 mRNA in osteopetrotic (op/op) mice. 1100 96