Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Protein kinase C (PKC) activation after treatment of human neuroblastoma SK-N-BE(2)C cells with phorbol 12-myristate 13-acetate (PMA) was found to enhance transcription of the human dopamine beta-hydroxylase (DBH) in those cells. To identify which cis-acting element is responsive to the PMA treatment during DBH gene expression, we employed transient transfection assays with serially deleted constructs of the human DBH gene's 5' upstream region fused to the chloramphenicol acetyltransferase (CAT) gene. Treatment of transfected cells with PMA resulted in an approximate threefold increase in CAT expression for all deletion constructs ranging from -978 bp to -262 bp, while the enhancement did not occur with a construct shortened to -114 bp. The region between -262 and -114 bp from the initiation site of transcription contains several cis-regulatory elements including a cyclic AMP response element (CRE) and putative AP1 and YY1 sequences. Site-directed mutagenesis of those cis-acting elements were performed to identify which of the elements mediated the PMA-induced transcriptional enhancement. Substitution of bases in the putative AP1 site containing in part a putative YY1 sequence did not effect the PMA inducibility. However, specific mutations in the CRE sequence abolished the PMA-inducible effect. Changing the CRE sequence into an authentic AP1 sequence (TGACGTCC --> TGACTCA) did not affect the PMA inducibility, suggesting that AP1 factors might interact with the new AP1 site upon PKC activation. A specific PKC inhibitor, GF109203X, completely inhibited the stimulatory effect of PMA on the expression of the human DBH gene. PMA induced an increase in the DBH mRNA level as detected by Northern blot analysis. Gel retardation showed that the binding of nuclear factors to CRE, putative YY1, and AP1 was sequence specific. Our data suggest that the enhancement of the human DBH gene expression by PMA treatment is mediated by the CRE motif in the 5' upstream region of the gene, and occurs via a PKC-dependent pathway.
Brain Res Mol Brain Res 1997 Nov
PMID:A protein kinase C-activating phorbol ester enhances transcription of the human DBH gene through a cyclic AMP response element in SK-N-BE(2)C cells. 942 17

Galactocerebrosidase (GALC) is the lysosomal enzyme deficient in human and certain animal species with globoid cell leukodystrophy (GLD) or Krabbe disease. It catalyzes the hydrolysis of specific galactolipids including galactosylceramide and psychosine. The GALC protein is found in very low amounts in all tissues, which delayed its purification and the subsequent cloning of its cDNA and gene. We previously published the exon-intron organization of the human gene, but did not functionally analyze the 5' flanking region. We now provide a description of this GC-rich region which includes one potential YY1 element and one potential SP1 binding site. There are 13 GGC trinucleotides within the first 150 bp preceding the initiation codon. The 5' end of intron 1 contains six potential Sp1 binding sites, one AP1 binding site, and eight AP2 binding sites. A construct containing nucleotides -176 to -24 had the strongest promoter activity using a vector containing the chloramphenicol acetyltransferase reporter gene. We also provide evidence for the presence of inhibitory sequences located immediately upstream of the promoter region, and within the first 234 nucleotides of intron 1. These elements together with a suboptimal nucleotide at position +4 may explain the low level of GALC protein in all cell types.
Biochem Mol Med 1997 Dec
PMID:Analysis of the 5' flanking region of the human galactocerebrosidase (GALC) gene. 944 67

Prostaglandin E2 (PGE2) enhances transcription of the human dopamine beta-hydroxylase (DBH) gene in human neuroblastoma SK-N-BE(2)C cells. To identify a PGE2-responsive cis-acting element in the human DBH gene, serial deletion constructs of the human DBH 5'-upstream region fused to the chloramphenicol acetyltransferase (CAT) reporter gene were transiently transfected into SK-N-BE(2)C cells. Treatment of the transformed cells with PGE2 increased CAT expression two- to threefold in all constructs except where the promoter region was shortened beyond position -114 bp. There are several cis-regulatory elements in the region between -262 and -114 bp from the transcription initiation site that include a cyclic AMP response element (CRE) and a putative AP1 sequence. We presupposed that the CRE and AP1 might be candidates for PGE2 stimulation, and therefore, used site-directed mutagenesis to change the CRE and AP1 motives and test which of the two elements mediated the transcriptional enhancement. Only a specific mutation within the CRE sequence abolished the PGE2 effect. In addition, cotransfection with an expression vector expressing PKA inhibitor resulted in the specific blockage of the PGE2 effect on DBH gene expression. Northern blot analysis revealed that the increase in DBH gene transcription caused by PGE2 results in elevated DBH mRNA levels. Gel-retardation and competition assays confirmed that the binding of nuclear factors to the CRE site is sequence specific. Our data, therefore, indicate that PGE2 enhances the transcription of the human DBH gene. The effect is mediated by the CRE motif through activation of PKA.
J Mol Neurosci 1997 Dec
PMID:Stimulation of human DBH gene expression by prostaglandin E2 in human neuroblastoma SK-N-BE(2)C cells. 948 16

The hypertrophic response is characterized by increased myofibril/sarcomere organization, induction of the cardiac specific atrial natriuretic factor (ANF) and myosin light chain-2 (MLC-2v) genes, and an increase in total cell volume. The alpha1-adrenergic agonist phenylephrine induces both the morphological and biochemical markers of hypertrophy in cultured neonatal rat ventricular cardiomyocytes. Previous studies have suggested a functional requirement for the heterotrimeric G-protein, Galphaq, for a subset of the hypertrophic phenotypes. The small GTPases Ras and Rho have also been implicated in phenylephrine-induced hypertrophy. To further delineate the role of Galphaq in hypertrophy, a constitutively active mutant of Galphaq was transiently transfected in primary rat ventricular cardiomyocytes. This molecule was sufficient to induce ANF-, AP1-, and MLC-2-driven gene expression. Co-transfection of Galphaq and dominant negative Ras or dominant negative Raf resulted in dose-dependent inhibition of ANF-driven expression. Both dominant negative Rho, and the Rho inhibitor C3-transferase, also attenuated Galphaq- and Ras-induced ANF-driven gene expression. Cells transfected with active Galphaq did not show a detectable increase in activation of the mitogen activated protein kinases ERK or SAPK. However, activity of the MAP-kinases appears to be important for Galphaq-induced gene expression since the MAP-kinase phosphatase Clone 100 and catalytically inactive SAPK strongly inhibited Galphaq-induced ANF expression. Thus, our studies indicate Galphaq-induced hypertrophic gene expression requires the small G-proteins Ras and Rho. The data also indicates that Galphaq mediated gene expression is dependent on functional MAP-kinases and that multiple signaling pathways contribute to Galphaq-mediated cardiac cell hypertrophy.
J Mol Cell Cardiol 1998 Mar
PMID:Ras and rho are required for galphaq-induced hypertrophic gene expression in neonatal rat cardiac myocytes. 951 26

The mechanisms responsible for coated pit formation in cells remain unknown, but indirect evidence has argued both for and against a critical role of receptor cytoplasmic domains in the process. If the endocytic motifs of receptors are responsible for recruiting AP2 to the plasma membrane, thereby driving coated pit formation, then the level of constitutively internalized receptors at the membrane would be expected to govern the steady-state level of coated pits in cells. Here we directly test this hypothesis for broad classes of receptors containing three distinct constitutive internalization signals. Chimeric proteins consisting of an integral membrane reporter protein (Tac) coupled to cytoplasmic domains bearing tyrosine-, di-leucine-, or acidic cluster/casein kinase II-based internalization signals were overexpressed to levels that saturated the internalization pathway. Quantitative confocal immunofluorescence microscopy indicated that the number of plasma membrane clathrin-coated pits and the concentration of their structural components were invariant when comparing cells expressing saturating levels of the chimeric receptors to nonexpressing cells or to cells expressing only the Tac reporter lacking cytoplasmic internalization signals. Biochemical analysis showed that the distribution of coat proteins between assembled coated pits and soluble pools was also not altered by receptor overexpression. Finally, the cellular localizations of AP2 and AP1 were similarly unaffected. These results provide a clear indication that receptor endocytic signals do not determine coated pit levels by directly recruiting AP2 molecules. Rather, the findings support a model in which coated pit formation proceeds through recruitment and activation of AP2, likely through a limited number of regulated docking sites that act independently of endocytic signals.
Mol Biol Cell 1998 May
PMID:Endocytic clathrin-coated pit formation is independent of receptor internalization signal levels. 957 Dec 48

The transcription factor AP1 has been implicated in the induction of apoptosis in cells in response to stress factors and growth factor withdrawal. We report here that AP1 is necessary for the induction of apoptosis following hormone withdrawal in the erythropoietin (EPO)-dependent erythroid cell line HCD57. AP1 DNA binding activity increased upon withdrawal of HCD57 cells from EPO. A dominant negative AP1 mutant rendered these cells resistant to apoptosis induced by EPO withdrawal and blocked the downregulation of Bcl-XL. JunB is a major binding protein in the AP1 complex observed upon EPO withdrawal; JunB but not c-Jun was present in the AP1 complex 3 h after EPO withdrawal in HCD57 cells, with a concurrent increase in junB message and protein. Furthermore, analysis of AP1 DNA binding activity in an apoptosis-resistant subclone of HCD57 revealed a lack of induction in AP1 DNA binding activity and no change in junB mRNA levels upon EPO withdrawal. In addition, we determined that c-Jun and AP1 activities correlated with EPO-induced proliferation and/or protection from apoptosis. AP1 DNA binding activity increased over the first 3 h following EPO stimulation of HCD57 cells, and suppression of AP1 activity partially inhibited EPO-induced proliferation. c-Jun but not JunB was present in the AP1 complex 3 h after EPO addition. These results implicate AP1 in the regulation of proliferation and survival of erythroid cells and suggest that different AP1 factors may play distinct roles in both triggering apoptosis (JunB) and protecting erythroid cells from apoptosis (c-Jun).
Mol Cell Biol 1998 Jul
PMID:AP1 regulation of proliferation and initiation of apoptosis in erythropoietin-dependent erythroid cells. 963 52

The amyloid beta-protein (Abeta) is the major proteinaceous component of the amyloid deposits that accumulate extracellularly in the brain of Alzheimer's disease (AD). Abeta is generated proteolytically from a larger beta-amyloid precursor protein (betaAPP). The apparent overexpression of the betaAPP gene in certain areas of AD brains indicate that abnormalities in gene regulation might be an important factor in AD. Here, I report that an upstream regulatory element (URE) located between -2257 to -2234 base pair (bp) of the human betaAPP promoter may interact with a novel protein(s) as determined by a gel shift assay. To determine whether this novel protein is related to an already characterized transcription factor, a gel shift assay was performed using various specific competitors in human neuroblastoma and rat pheochromocytoma (PC12) cells. The labeled URE probe could interact with a distinct nuclear factor which was not competed by the oligonucleotides specific for the different transcription factors, AP1, AP2, AP3, GRE, Oct1, NF1 and NF-kappaB. Alternatively the specific protein band(s) detected with either the labeled NF-kappaB or NF1 probe could not be competed out with an excess of unlabeled URE. To determine if such a band could be detected in human brain tissue samples, a gel shift assay from the nuclear extracts of the human brain was performed. A distinct URE-specific nuclear factor was detected in different regions of the brain as well. To determine the size of the protein(s) that were specifically bound in the DNA-protein complexes, Southwestern blotting was performed. Using the URE probe, two major protein bands of approximately 53 and 116 kDa were detected in PC12 nuclear extracts. These results suggest that the protein factor(s) interacting with URE is not related to the known transcription factors tested, and that the protein is expressed in certain cell types and different regions of the human brain.
Brain Res Mol Brain Res 1998 Jul 15
PMID:An region upstream of the gene promoter for the beta-amyloid precursor protein interacts with proteins from nuclear extracts of the human brain and PC12 cells. 968 2

The complement C3a anaphylatoxin receptor (C3aR) is a seven-transmembrane G-protein coupled chemoattractant receptor that on binding the C3a peptide ligand mediates numerous cellular responses, including histamine release from mast cells. smooth muscle contraction, and the directed migration of eosinophils. To delineate the murine C3aR coding sequence, gene structure, 5'-flanking region, and chromosome location, cDNA and genomic clones encoding the mouse C3a receptor were isolated, characterized, and used in fluorescence in situ hybridization experiments. The results from this study indicate that the murine C3a receptor structural gene is a single copy gene of approximately 8 kb comprised of 2 exons which are separated by a large intervening intron of 4724 bp. The first exon encodes 97 bp of 5'-untranslated sequence. Exon 2 encodes the remaining 8 bp of 5'-untranslated sequence and the entire coding and 3'-untranslated sequences. This genomic organization is typical of most other chemoattractant receptor genes in that the entire coding sequence is contained on a single exon. The human and mouse C3a receptor genes were localized to syntenic chromosomal bands 12q13.2-3 and 6F1, respectively. No other seven-transmembrane receptor genes, to date, have been localized to these chromosomal regions. Primer extension experiments using mouse macrophage RNA indicated a single transcriptional initiation site. Sequence analysis 5' of the transcriptional site indicated a TATA-less promoter with possible cis-acting motifs that may regulate C3a receptor gene expression. These included the recognition sequence for the nuclear transcription factor SP1 and the phorbol ester response sequence which binds the Fos/Jun heteromeric transcription factor AP1.
Mol Immunol 1998 Feb
PMID:Cloning, expression, sequence determination, and chromosome localization of the mouse complement C3a anaphylatoxin receptor gene. 969 14

The tumor promoter, okadaic acid (OA), an inhibitor of protein phosphatases, stimulates the activity of the human PRL (hPRL) proximal promoter. We analyzed in detail the effects of OA on transcription factor binding to elements P1 and P2 of this promoter, sequences known to contain at least one Pit-1 binding site each. OA treatment induces binding of an AP1-related transcription factor to the P1 site. This effect is specific, as protein binding to the P2 site is not altered by the treatment. Specific antibodies were used to confirm that the OA-induced complex is related to AP1 and to show that it contains JunD and c-fos, but not Pit-1. The increase in AP1 binding to P1 and to a canonical AP1 site correlates to an increase in cellular JunD and c-fos content. Transient transfection experiments showed that both AP1 and Pit-1 are involved in the regulation of basal and OA-stimulated promoter activity. Our results demonstrate that a member of the AP1 family, containing JunD and c-fos, can bind to the proximal element P1 within the hPRL promoter. In addition, they show that AP1 is involved in both basal and OA-stimulated expression of the hPRL gene.
Mol Endocrinol 1998 Aug
PMID:Transcription factor AP1 is involved in basal and okadaic acid-stimulated activity of the human PRL promoter. 971 47

FGF-1 mRNA is expressed in the prostate cancer cell lines LNCaP and PC-3 and in the breast carcinoma cell line MDA-MB-231. Levels of FGF-1 mRNA have been shown to be up-regulated by serum, phorbol esters, and combinations of growth factors. It was shown that the major FGF-1 mRNA species expressed following serum stimulation in MDA-MB-231 cells is FGF-1.C. To better understand the potential role of FGF-1 in human prostate and breast cancer, we began an analysis of the cis- and trans-acting elements of one of its promoters required for the serum, PMA, and androgen regulation in breast and prostate cancer cell lines. We show that FGF-1.C steady-state mRNA levels are increased following serum or PMA stimulation of PC-3 cells. Further, we determine the FGF-1.C transcription start site in PC-3 cells. By sequence analysis, we show that consensus AP1, AP2, and Sp1 sites and ARE- and CRE-near consensus elements are present in the immediate 5' region of the FGF-1.C transcription start site. Gel-shift assays show that oligonucleotides containing FGF-1.C AP1, AP2, or Spl sequences form specific DNA-protein complexes with nuclear extracts from PC-3 cells. To determine if these or other cis-acting sequences are responsible for the serum, androgen, or growth factor regulation of FGF-1 expression, fragments of the FGF-1.C promoter region were cloned upstream of the luciferase reporter gene. We show that FGF-1 synergizes with androgen to enhance FGF-1.C transcription in LNCaP cells. We further show that the DNA fragment containing sequence up to 1614 nucleotides upstream of the FGF-1.C transcription start site is sufficient for stimulating promoter activity following serum treatment of MDA-MB-231 cells. Thus, FGF-1.C promoter contains sequences that are important for androgen or serum stimulation in prostate and breast cancer cells.
J Steroid Biochem Mol Biol 1998 Aug
PMID:Regulation of a promoter of the fibroblast growth factor 1 gene in prostate and breast cancer cells. 971 43


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