Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.28 (chloramphenicol acetyltransferase)
 5,100 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Interferon-tau (oIFNtau), the major secretory product of ovine conceptuses between days 13 and 21 (day 0=day of estrus) of pregnancy, is implicated in the process of maternal recognition of pregnancy. Culturing of day-14 and day-16 conceptus tissues in the presence of human granulocyte macrophage-colony stimulating factor (hGM-CSF) or interleukin-3 (IL-3) produces a marked increase in oIFNtau mRNA and protein expression. Since GM-CSF and IL-3 are localized at the luminal and glandular epithelia of the ovine endometrium, maternally derived GM-CSF and IL-3 may affect conceptus production of oIFNtau in a paracrine manner. However, the molecular mechanisms by which endometrial GM-CSF and IL-3 up-regulate oIFNtau production have not been defined. As an initial investigation of the signaling pathway regulating the GM-CSF induction of the oIFNtau gene, day-16 conceptuses were treated with an inducer, phorbol 12-myristate 13-acetate (PMA) and an inhibitor, calphostin C of the protein kinase C (PKC) pathway. Treatment with either 150 units/ml hGM-CSF (P<0.01) or 10 nM PMA (P<0.05) resulted in a significant increase in oIFNtau mRNA expression. Pretreatment of conceptuses with 1 microM PMA for 12 h to produce PKC-deficient tissues or treatment with 50 mM calphostin C abolished the hGM-CSF-induced increase in oIFNtau mRNA. An in vitro expression system was established for the analysis of oIFNtau gene regulatory sequences. The oIFNtau010 gene has been isolated previously and found to be the principal oIFNtau gene up-regulated during the preimplantation period. 5'-Flanking regions of the oIFNtau010 gene, 2 kb and 0.8 kb, were cloned into a basic chloramphenicol acetyltransferase reporter plasmid. These oIFNtau010 promoter constructs, along with expression controls, were transfected into human choriocarcinoma cells (JAR and JEG3) and their responsiveness to hGM-CSF and second messenger system activators including PMA, calcium ionophore (A23187) and 8-bromo-cAMP were characterized. The oIFNtau010 promoter constructs were up-regulated by hGM-CSF and PMA treatments (P<0.01). Combined treatment with PMA and A23187 prevented the promoter activation seen with PMA alone. The conceptus culture data, along with the results from the transfection experiments, suggest that the stimulatory effect of GM-CSF on oIFNtau is mediated through the PKC second messenger system.
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PMID:Enhancement of ovine trophoblast interferon by granulocyte macrophage-colony stimulating factor: possible involvement of protein kinase C. 934 4

Human T-cell leukemia virus type-I (HTLV-I), the etiologic agent of adult T-cell leukemia (ATL) transforms human T cells both in vivo and in vitro. However, the long latency period between infection and development of ATL, as well as the small fraction of the infected population that actually develops this disease, suggest that factors in addition to the virus are involved in its pathogenesis. Mutation of tumor suppressor gene p53 has been found in both HTLV-I-transformed T-cell lines and ATL cases at relatively low frequency. However, increasing evidence supports p53 functional impairment in HTLV-I-transformed T cells. Tax, the major transactivator of HTLV-I, is critical for the initial events involved in transformation. We have considered the possibility that p53 may regulate transcription of viral and cellular genes important for viral replication and transformation. Inactivation of p53 function might then permit constitutive expression of these viral and cellular genes. We have investigated the effects of wild-type and mutant p53 on Tax-mediated activation of the HTLV-I long terminal repeat (LTR) and the promoters of several cellular genes including the interleukin (IL)-1alpha, IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF ), and IL-2 receptor alpha chain gene. Jurkat, HuT78, and U937 cells were cotransfected with plasmids containing a chloramphenicol acetyltransferase (CAT ) reporter gene under viral or cellular promoter control and the Tax expression vector, in addition to vectors for a wild-type or mutant p53. Wild-type p53 is a potent repressor of viral and cellular activation by Tax. Mutations within p53 severely inhibit this downregulation. We also show that wild-type p53 suppresses transcription from the HTLV-I LTR in Jurkat-Tax, a T-cell line stably expressing Tax, and MT-2, a HTLV-I-transformed T-cell line. Wild-type, but not mutant, p53 interfered with the binding of TATA-binding protein (TBP) to the TATA motif of the HTLV-I LTR. These results suggest that p53 inactivation may lead to upregulation of viral and cellular genes and may also be important for establishment of productive viral infection and development of ATL.
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PMID:Repression of transcription from the human T-cell leukemia virus type I long terminal repeat and cellular gene promoters by wild-type p53. 938 10

We demonstrate here that intracerebroventricular or spinal cord (intrathecal) injection of either plasmid DNA alone or cationic liposome: DNA complexes (CLDCs) produces significant levels of expression of both reporter genes and biologically relevant genes in nonparenchymal cells lining both the brain and the spinal cord. Gene expression was identified both within the spinal cord and the brain after intracerebroventricular or intrathecal injection of either CLDCs or plasmid DNA alone. Intracerebroventricular or intrathecal injection of CLDCs containing the beta-galactosidase (beta-Gal) gene produced patchy, widely scattered areas of beta-Gal expression. The chloramphenicol acetyltransferase (CAT) reporter gene product reached peak levels between 24 hr and 1 week postinjection, and was still present at significant levels 3 weeks after a single intracerebroventricular or intrathecal injection. Intrathecal injection of the human granulocyte colony-stimulating factor (G-CSF) gene produced high levels of hG-CSF activity in both the spinal cord and the brain. Intracerebroventricular injection of CLDCs containing the murine nerve growth factor (NGF) gene increased mNGF levels in the hippocampus, a target region for cholinergic neurons in the medial septum, and increased cholinergic neurotransmitter synthetic enzyme choline acetyltransferase (ChAT) activity within the brain, a well-characterized effect of both purified and recombinant NGF protein. These findings indicate that intracerebroventricular or intrathecal injection of CLDCs can produce significant levels of expression of biologically and therapeutically relevant genes within the CNS. Efficient gene transfer into the CNS will facilitate the evaluation of gene function and regulation within the brain and spinal cord. We attempted to transfer and express genes within the brain and spinal cord by direct CNS injection of either DNA alone or CLDCs into the intraventricular and subarachnoid compartments. We show that intracerebroventricular or spinal cord (intrathecal) injection of either plasmid DNA alone or CLDCs produces significant levels of expression of both reporter genes and biologically relevant genes in nonparenchymal cells lining both the brain and the spinal cord. Intrathecal injection of the hG-CSF gene produced high levels of hG-CSF activity in both the spinal cord and the brain. Intracerebroventricular injection of CLDCs containing the murine NGF gene increased mNGF levels in the hippocampus, and increased cholinergic neurotransmitter synthetic enzyme ChAT activity within the brain. Locoregional diffusion of gene products expressed by transfected meningeal lining cells into brain and spinal cord parenchyma could potentially target secreted proteins within brain and spinal cord regions relevant to neuropathological states while limiting peripheral side effects.
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PMID:Gene expression along the cerebral-spinal axis after regional gene delivery. 1056 97

In utero injection of cationic liposome-DNA complexes (CLDCs) containing chloramphenicol acetyltransferase, beta-galactosidase (beta-gal), or human granulocyte colony-stimulating factor (hG-CSF) expression plasmids produced high-level gene expression in fetal rats. Tissues adjacent to the injection site exhibited the highest levels of gene expression. Chloramphenicol acetyltransferase expression persisted for at least 14 days and was reexpressed following postnatal reinjection of CLDCs. Intraperitoneal administration of the hG-CSF gene produced high serum hG-CSF levels. X-gal staining demonstrated widespread beta-gal expression in multiple fetal tissues and cell types. No toxic or inflammatory responses were observed, nor was there evidence of fetal-maternal or maternal-fetal gene transfer, suggesting that CLDCs may provide a useful alternative to viral vectors for in utero gene transfer.
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PMID:Fetal gene transfer by transuterine injection of cationic liposome-DNA complexes. 1058 16

We have recently shown that IL-3R occupancy activates a phosphatidylcholine-specific phospholipase C, and the sustained diacylglycerol accumulation subsequently activates protein kinase C (PKC). In human IL-3-dependent myeloid cells (TF-1), the novel PKCepsilon isoform regulates bcl-2 expression and cell survival. The report of a PKC activatable cAMP response element (CRE) in the bcl-2 promoter and a role for PKC in bcl-2 expression in B cells led us to the hypothesis that PKC phosphorylation activates transcription factor CREB after IL-3R engagement. We found that IL-3 and GM-CSF induced phosphorylation of CREB on Ser(133) in TF-1 cells, and this phosphorylation was blocked by two structurally unrelated classes of PKC inhibitors. An inhibitor of cyclic nucleotide-dependent kinases did not block this phosphorylation. IL-4, which is biologically active in these cells but does not use the beta common subunit, did not phosphorylate CREB on Ser(133). Inhibition of mitogen-activated protein kinase kinase activity also inhibited IL3-induced CREB phosphorylation. The PKC inhibitors, but not a cyclic nucleotide-dependent kinase inhibitor, blocked IL-3 activation of CRE-dependent transcription from an egr-1 promoter/chloramphenicol acetyltransferase (CAT) reporter construction transiently transfected into TF-1 cells. Finally, TF-1 cells stably overexpressing PKCepsilon, but not the delta isoform of PKC, enhanced CRE-dependent CAT expression from the promoter/reporter construction. Therefore, it is likely that a PKCepsilon kinase cascade resulting in CREB phosphorylation represents a novel signal transduction cascade for regulating cellular gene expression through the beta common cytokine receptor.
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PMID:betac cytokine receptor-induced stimulation of cAMP response element binding protein phosphorylation requires protein kinase C in myeloid cells: a novel cytokine signal transduction cascade. 1159 53


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