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

---

Query: EC:3.1.27.1 (RNase)
16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to examine the regulation of cytokine receptor gene expression an RNase protection assay (RPA) was developed that allows the simultaneous and semiquantitative measurement of mRNAs encoding for the IL-1 p60 and p80, TNF p55 and p75, IFN-gamma, and IL-6 receptors. Titration experiments revealed that this method was very sensitive allowing the detection of the target cytokine receptor mRNAs down to at least 0.01 microgram of spleen poly(A)+ RNA. The cytokine receptor RPA was used to examine the expression of the receptor genes in various organs from normal mice and mice that had been injected with LPS. In normal mice expression of the IL-1R p80, TNFR p55 and p75, IFN-gamma, and IL-6R but not the IL-1R p60 transcripts was readily detectable in spleen, liver, kidney, and brain. Following LPS treatment, there was an induction of the IL-1R p60 mRNA in all organs and an up-regulation of the IL-1R p80, TNFR p55 and p75, IFN-gamma, and IL-6 receptor mRNAs particularly in spleen, liver, and kidney. Interorgan differences were observed in the regulation of these receptor mRNAs, indicating an organ-specific response to the LPS challenge. Our findings indicate the cytokine receptor RPA is a powerful and versatile tool for the simultaneous analysis of multiple cytokine receptor mRNAs in tissue samples. This technique will prove valuable in further evaluating the coordinated regulation of the expression of these genes, which are pivotal in the biology of cytokines.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Simultaneous analysis of multiple cytokine receptor mRNAs by RNase protection assay in LPS-induced endotoxemia. 806 Nov 11

The interleukin-2 (IL-2) receptor gamma chain is an essential component of high and intermediate affinity IL-2 receptors (IL-2Rs), playing critical roles for ligand binding and internalization. We report here the isolation and characterization of the genomic locus for human IL-2R gamma, which, like IL-2R beta, is a member of the cytokine receptor superfamily. The IL-2R gamma gene is composed of eight exons and seven introns and spans approximately 4.2 kilobases. Analogous to the IL-2R beta gene, the two pairs of conserved cysteines typical of cytokine receptor superfamily proteins are located in adjacent exons, and the conserved WSXWS motif is located in the exon preceding the one that encodes the transmembrane domain and a small part of the cytoplasmic domain. In each gene, the remainder of the cytoplasmic domain is encoded by the final two exons. Southern blot analysis suggests that IL-2R gamma is encoded by a single copy gene. Cross-hybridizing sequences were detected in DNA derived from a number of other mammalian species but not from yeast. Primer extension analysis and ribonuclease protection assays revealed that there are three principal transcription initiation sites located 32-38 nucleotides 5' to the translation initiation AUG codon. These sites are upstream of the 5' end of the published IL-2R gamma cDNA sequence. The region 5' to the transcription initiation sites exhibited promoter activity when cloned upstream of the luciferase reporter gene. With this study, the organization of the genes encoding all three chains (alpha, beta, and gamma) of the IL-2 receptor has been determined and promoters for each identified.
...
PMID:Characterization of the human interleukin-2 receptor gamma chain gene. 851 92

The GH receptor (GHR) is a member of the cytokine receptor family. Short isoforms resulting from alternative splicing have been reported for a number of proteins in this family. RT-PCR experiments, in human liver and cultured IM-9 cells, using primers in exon 7 and 10 of the GHR, revealed three bands reflecting alternative splicing of GHR mRNA: the predicted product at 453 bp and two other products at 427 and 383 bp. The 427-bp product (GHR1-279) utilized an alternative 3'-acceptor splice site 26 bp downstream in exon 9; the predicted C-terminal residues are six frameshifted exon 9 codons ending in an inframe stop codon. The 383-bp product (GHR1-277) resulted from skipping of exon 9; the predicted C-terminal residues are three frame-shifted exon 10 codons ending in an in-frame stop codon. RNase protection experiments confirmed the presence of the GHR1-279 variant in IM-9 cells and human liver. The proportion of alternative splice to full length was 1-10% for GHR1-279 and less than 1% for GHR1-277. The function of GHR1-279 was examined after subcloning in an expression vector and transient transfection in 293 cells. Scatchard analysis of competition curves for [125l]-hGH bound to cells transfected either with GHR full length (GHRfl) or GHR1-279 revealed a 2-fold reduced affinity and 6-fold increased number of binding sites for GHR1-279. The increased expression of GHR1-279 was confirmed by cross-linking studies. The media of cells transfected with GHR1-279 contained 20-fold more GH-binding protein (GHBP) than that found in the media of cells transfected with the full-length receptor. Immunoprecipitation and Western blotting experiments, using a combination of antibodies directed against extracellular and intracellular GHR epitopes, demonstrated that GHRfl and GHR1-279 can form heterodimers and that the two forms also generate a 60-kDa GHBP similar in size to the GHBP in human serum. Functional tests using a reporter gene, containing Stat5-binding elements, confirmed that while the variant form was inactive by itself, it could inhibit the function of the full-length receptor. We have demonstrated the presence of a splice variant of the GHR in human liver encoding a short form of the receptor similar in size to a protein previously identified in human liver and choroid plexus. Expression studies in 293 cells support the hypothesis that while the expression of the splice variant accounts for only a small proportion of the total GHR transcript, it produces a short isoform that modulates the function of the full-length receptor, inhibits signaling, and generates large amounts of GHBP. The differential expression of GHR receptor short forms may regulate the production of GHBP, and truncated receptors may act as transport proteins or negative regulators of GHR signaling.
...
PMID:A short isoform of the human growth hormone receptor functions as a dominant negative inhibitor of the full-length receptor and generates large amounts of binding protein. 905 73

The signalling mechanisms that regulate epidermal permeability barrier homeostasis are not known. Previous Northern blot analysis showed that both acute and chronic barrier disruption increase mRNA levels of several cytokines in murine epidermis. To further characterize the epidermal response to barrier abrogation, we used more sensitive, multi-probe RNase protection assays to measure the mRNA levels of additional cytokines, as well as cytokine receptors in acute and chronic models of barrier disruption. Normal mouse epidermis expressed interleukin (IL)-1 alpha, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) and IL-6 mRNAs. Following tape-stripping, only the mRNA levels for TNF-alpha, IL-1 alpha, IL-1 beta and IL-6 increased at 2.5 and 7 h, and returned toward normal levels by 18 h. No mRNAs encoding TNF-beta, IL-2, IL-3, IL-4 or IL-5, were detected in the epidermis either under basal conditions or after tape-stripping. Similarly, in a chronic model, essential fatty acid deficiency, epidermal levels of TNF-alpha, IL-1 alpha, IL-1 beta and IL-6 mRNAs, but not IFN-gamma mRNA, were elevated over controls; and again, mRNAs for the remaining probed cytokines were not detected. In contrast, in the dermis, only IL-1 beta mRNA levels increased 2.5 h after tape-stripping, and remained elevated at 18 h. mRNAs encoding the IL-1 (p60), IFN-gamma and IL-6 receptors were present in epidermis, but their levels remained unchanged following either acute or chronic barrier disruption. In contrast, epidermal TNF (p55) receptor mRNA levels were increased by 87% (P < 0.01) at 2.5 h, returned to control levels at 7 h and were increased by 68% (P < 0.03) at 18 h after tape-stripping. The increase at 2 h was confirmed by Northern blot analysis and was not prevented by latex occlusion performed immediately after tape-stripping mRNAs for the IL-1 (p80) receptor and TNF (p75) receptor were not detected in epidermis. Low levels of TNF (p55) receptor mRNA were present in the dermis, and they remained unchanged after tape-stripping. The presence of specific receptor mRNAs in the epidermis and dermis suggests that these tissues are capable of responding in an autocrine and/or paracrine fashion to the cognate cytokines. These results suggest that epidermal cytokines produced after barrier disruption may initiate a cytokine cascade which could regulate cytokine and cytokine receptor production and/or inflammatory responses.
...
PMID:Barrier disruption increases gene expression of cytokines and the 55 kD TNF receptor in murine skin. 920 92

The PRL receptor (PRL-R) signals through the Janus tyrosine kinases (JAK) and other non-JAK tyrosine kinases, some of which are preassociated with the PRL-R. To clone PRL-R interacting proteins, the intracellular domain (ICD) of the long form of the PRL-R was used in a yeast two-hybrid screen of a human B cell cDNA library. One PRL-R interacting protein was identified as the 42-kDa form of the enzyme 2',5'-oligoadenylate synthetase (OAS). The in vivo interactions in yeast were further confirmed by an in vitro interaction assay and by coimmunoprecipitation in transfected mammalian cells. Functionally, OAS reduced the basal activity of two types of promoters in transiently transfected COS-1 cells. In the presence of PRL, OAS inhibited PRL induction of the immediate early IRF-1 (interferon-regulatory factor 1) promoter, but not PRL induction of the differentiation-specific beta-casein promoter, suggesting that OAS exerts specific effects on immediate early gene promoters. The inhibitory effects of OAS were accompanied by a reduction in PRL-inducible Stat1 (signal transducer and activator of transcription 1) DNA binding activity at the IRF-1 GAS (interferon-gamma-activated sequence) element. These results demonstrate a novel interaction of OAS with the PRL-R and suggest a role for OAS in modulating Stat1-mediated signaling to an immediate early gene promoter. Although previously characterized as a regulator of ribonuclease (RNase) L antiviral responses, OAS may have additional effects on cytokine receptor signal transduction pathways.
...
PMID:Association of 2',5'-oligoadenylate synthetase with the prolactin (PRL) receptor: alteration in PRL-inducible stat1 (signal transducer and activator of transcription 1) signaling to the IRF-1 (interferon-regulatory factor 1) promoter. 1067 1

Endogenous and exogenous kappa-opioid agonists have been widely reported to modulate the immune response. We have published results that show that the superantigen-induced proliferative response of thymocytes is inhibited by the selective kappa-opioid agonist trans-3, 4-dichloro-N-methyl-N-[2-(1-pyrolidinyl)cyclohexyl] benzeneaceamide methanesulfonate (U50,488H). Previous work has established that the kappa-opioid receptor is widely expressed within the thymus; however, little is known about the role of the kappa-opioid receptor in the function of thymocytes. In the present report, we have examined the impact of U50,488H administration on the expression of cytokines in superantigen-stimulated thymocytes by RNase protection analysis. We have measured detectable levels of the cytokines IL-2, IL-4, IL-5, IL-13, and IFN-gamma, and the chemokines lymphotactin and RANTES, in stimulated thymocyte cultures; however, addition of U50,488H did not alter the expression of these cytokines. Examination of cytokine receptor expression by these thymocytes revealed a significant inhibition in the expression of the transcript for the IL-7 receptor alpha-chain (IL-7Ralpha), and these results were confirmed by flow cytometry. Surprisingly, the expression of several other cytokine receptor chains including the common gamma-chain, IL-2Rbeta, or the IL-2Ralpha, IL-4Ralpha, and IL-15Ralpha chains, was not altered. In contrast to these results, a significant elevation in the expression of the chemokine receptor CCR2 was observed in U50,488H-treated cultures. These results suggest that the kappa-opioid receptor may function to promote cellular migration at the expense of the sensitivity to the growth-promoting/maturation activity of IL-7.
...
PMID:Kappa-opioid regulation of thymocyte IL-7 receptor and C-C chemokine receptor 2 expression. 1079 65

In diadromous and euryhaline teleosts, it has been established that prolactin (PRL) is a major hormone regulating the maintenance of water and electrolyte homeostasis by acting on its receptor (PRLR) expressed in the osmoregulatory organs. To investigate the major physiological role of PRL in a marine teleost, cDNA for the Japanese flounder (Paralichtys olivaceus) prolactin receptor (fPRLR) has been cloned and characterized. The predicted fPRLR is composed of 636 amino acids conserving common structural features, such as the WSXWS motif and box 1, that are observed in the members of the cytokine receptor superfamily. By Northern blot analysis, 3.5-kb transcripts for fPRLR were clearly detected in the gill, kidney, and intestine. By RNase protection assay, similarly high levels of mRNA expression were detected in these osmoregulatory organs and lower expression levels were seen in the brain for both males and females. Interestingly, a distinct expression level of fPRLR mRNA was observed in the testis, but not in the ovary. The present results suggest that PRL may play an important role in the control of water and electrolyte balance through PRLR expressed in the osmoregulatory organs in the marine teleost the Japanese flounder as well as in other teleosts. Furthermore, PRL may differentially regulate gonadal functions in males and females of Japanese flounder.
...
PMID:Structure and tissue distribution of prolactin receptor mRNA in Japanese flounder (Paralichtys olivaceus): conserved and preferential expression in osmoregulatory organs. 1148 38

PRL has been reported to regulate fat metabolism in several species. We recently reported PRL receptor (PRLR) expression in mouse adipocytes and increased levels of PRLR expression in the adipose tissue of lactating and PRL-transgenic mice compared with controls. These results suggest PRLR-mediated effects in adipose tissue. However, to date most studies have been performed in vivo, and it is unclear whether PRL has direct effects on adipocytes. The PRLR belongs to the cytokine receptor family, and a family of suppressors of cytokine signaling (SOCS) was recently identified. The present study was performed to investigate whether PRL has direct effects on adipocytes. The expression of cytokine-inducible SH2-domain-containing protein (CIS), SOCS-3, and SOCS-2 mRNA and protein was analyzed using ribonuclease protection assay and immunoblotting, respectively. Ovine PRL induced CIS mRNA expression and a combination of oPRL and insulin induced SOCS-3 mRNA expression in adipocytes cultured in vitro for 0-240 min, demonstrating PRLR-mediated direct effects in these cells. Furthermore, CIS, SOCS-3, and SOCS-2 mRNA and protein were all transiently expressed in adipose tissue obtained from female mice stimulated with oPRL (1 microg/g BW) for 0-24 h. In adipose tissue of female mice with endogenously high PRL levels, PRL-transgenic mice, only SOCS-2 expression was increased. The level of SOCS-2 mRNA was also increased in adipose tissue during pregnancy and lactation compared with that in wild-type virgin female mice. A possible reason for increased SOCS-2 expression after prolonged PRL exposure during lactation and in the PRL transgenes could be to restore the sensitivity of adipose tissue to PRL. In addition, the direct effect of PRL on leptin production was investigated in adipocytes cultured in vitro for 6 h. PRL inhibited insulin-induced leptin production in vitro. However, PRL had no effect on leptin production in the absence of insulin. In contrast, serum leptin concentrations were increased in PRL-transgenic females compared with control mice. In conclusion, our results demonstrate functional PRLRs in mouse adipocytes and suggest a role for CIS, SOCS-3, and SOCS-2 in regulating PRL signal transduction in adipose tissue.
...
PMID:PRL receptor-mediated effects in female mouse adipocytes: PRL induces suppressors of cytokine signaling expression and suppresses insulin-induced leptin production in adipocytes in vitro. 1160 56

Immunotherapies, although promising in preclinical studies, have not yet enhanced the survival of patients with glioblastomas. To further understand the immunobiology of glioblastomas in clinical settings, we examined 53 cytokine or cytokine receptor transcripts in 12 human glioblastomas and 6 human glioblastoma cell lines and correlated the findings with the degree of inflammation. Multi-probe RNase protection assays were used to examine Th1, Th2, and Th3 cytokine and cytokine receptor expression. Th2 [interleukin (IL)-6, leukemia inhibitory factor and oncostatin M] and Th3 (transforming growth factor-beta1, 2, 3) cytokine and their receptor transcripts were strongly expressed in almost all glioblastomas and glioma cell lines. Two other Th2 cytokine receptor subunit transcripts (IL-4Ralpha and IL-13Ralpha) were also commonly detected. In contrast, although Th1 cytokine receptors tumor necrosis factor (TNF) RI, interferon (IFN)-gammaRalpha, IFN-gammaRbeta, were detected, their cytokines (IFN-gamma, TNF-alpha, lymphotoxin-alpha) were not. Transcripts for IL-2 family cytokine (IL-2, IL-7, IL-9, IL-15) and receptors (IL-2Ralpha, IL-2Rbeta, gammac, IL-7Ralpha, IL-9Ralpha, IL15Ralpha) and IL-12 family cytokine (IL-12p40) and receptors (IL-12Rbeta1 and IL-12beta2) were essentially absent in both tumors and cell lines. Immunohistochemical methods showed sparse T lymphocyte infiltrates and numerous microglia in the glioblastomas. This pattern indicates an 'immunosuppressive status' in glioblastomas and could account for the failure of immunotherapy in such tumors.
...
PMID:Cytokine and cytokine receptor mRNA expression in human glioblastomas: evidence of Th1, Th2 and Th3 cytokine dysregulation. 1181 Jan 84

Platelet-derived growth factor (PDGF) is a potent stimulant of smooth muscle cell migration and proliferation in culture. To test the role of PDGF in the accumulation of smooth muscle cells in vivo, we evaluated ApoE -/- mice that develop complex lesions of atherosclerosis. Fetal liver cells from PDGF-B-deficient embryos were used to replace the circulating cells of lethally irradiated ApoE -/- mice. One month after transplant, all monocytes in PDGF-B -/- chimeras are of donor origin (lack PDGF), and no PDGF-BB is detected in circulating platelets, primary sources of PDGF in lesions. Although lesion volumes are comparable in the PDGF-B +/+ and -/- chimeras at 35 weeks, lesions in PDGF-B -/- chimeras contain mostly macrophages, appear less mature, and have a reduced frequency of fibrous cap formation as compared with PDGF-B +/+ chimeras. However, after 45 weeks, smooth muscle cell accumulation in fibrous caps is indistinguishable in the two groups. Comparison of elicited peritoneal macrophages by RNase protection assay shows an altered cytokine and cytokine receptor profile in PDGF-B -/- chimeras. ApoE -/- mice were also treated for up to 50 weeks with a PDGF receptor antagonist that blocks all three PDGF receptor dimers. Blockade of the PDGF receptors similarly delays, but does not prevent, accumulation of smooth muscle and fibrous cap formation. Thus, elimination of PDGF-B from circulating cells or blockade of PDGF receptors does not appear sufficient to prevent smooth muscle accumulation in advanced lesions of atherosclerosis.
...
PMID:Blockade of platelet-derived growth factor or its receptors transiently delays but does not prevent fibrous cap formation in ApoE null mice. 1236 12


1 2 Next >>

---