Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three alpha 1-adrenergic receptors (ARs) have been cloned, i.e., the alpha 1B-, alpha 1C-, and alpha 1D-ARs. Compared with the alpha 1B subtype, the alpha 1A subtype in tissue is described as being insensitive to chloroethylclonidine and sensitive to SZL-49 and having a 10-100-fold higher affinity for a number of agonists and antagonists. The alpha 1A subtype is also expressed in a variety of rat tissues (as assessed by pharmacology), with greatest abundance in the cerebral cortex, hippocampus, vas deferens, and submaxillary gland. The cloned bovine alpha 1C-AR, though having an alpha 1A-AR pharmacology, was first reported as not being expressed in any rat tissue (as determined by Northern analysis) and was therefore designated as a new subtype. We report the cloning, expression, and characterization of the rat homolog of the bovine alpha 1C-AR. Using a human alpha 1C-AR probe obtained by polymerase chain reaction screening of a neuroblastoma cell line (SK-N-MC), both exon 1 and exon 2 of the rat alpha 1C-AR gene were cloned from a rat genomic library. These two exons were spliced together and cloned into the expression vector pMT2'. Transfection into COS-1 cells and analysis of the ligand-binding profile of the expressed protein receptor using 125I-HEAT revealed a 10-100-fold higher affinity for the alpha 1-AR antagonists 5-methylurapidil, (+)-niguldipine, WB-4101, and phentolamine and the agonists oxymetazoline and methoxamine, compared with the alpha 1B-AR. This ligand-binding profile is similar to that for endogenously expressed tissue alpha 1A-ARs. In addition, the rat alpha 1C-AR was the least sensitive of the three cloned subtypes to the alkylating effects of chloroethylclonidine but was the most sensitive to the alkylating prazosin analog SZL-49, properties also observed for the tissue alpha 1A subtype. Furthermore, by three different techniques, i.e., RNase protection assays, reverse transcription-polymerase chain reaction Northern blotting, and in situ hybridization histochemistry, the rat alpha 1C-AR mRNA was localized to alpha 1A-AR-rich tissues, such as rat vas deferens, hippocampus, aorta, and submaxillary gland. Taken together, these data suggest that this receptor may actually represent the alpha 1A subtype.
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PMID:Cloning, expression, and tissue distribution of the rat homolog of the bovine alpha 1C-adrenergic receptor provide evidence for its classification as the alpha 1A subtype. 796 68

The phosphoinositidase C-linked G proteins Gq alpha and G11 alpha are highly similar and comigrate in 10% (w/v) acrylamide SDS-PAGE. Antisera generated against regions common between these G proteins thus detect a composite of the two polypeptides following resolution in such gels. Using SDS-PAGE conditions which allow resolution of Gq alpha and G11 alpha in rodent brain and neuroblastoma cell lines it was observed that primate frontal cortex and neuroblastoma cell lines did not express a polypeptide which comigrated with rodent G11 alpha. Species diversity in G-protein sequences is extremely limited; however, immunoblotting primate cells and frontal cortex with a G11 alpha-specific antiserum demonstrated this to be due to a difference in mobility of rodent and primate G11 alpha under these conditions rather than lack of expression of G11 alpha by primates. A cDNA encoding mouse G11 alpha was transiently expressed in monkey COS-1 cells and membranes from these cells were immunoblotted with antisera able to identify primate and rodent G11 alpha equally, following SDS-PAGE under the resolving conditions. Both mouse and monkey G11 alpha could be detected concurrently and unambiguously following transfection. This is the first demonstration that species variants of the same G protein expressed in a single cell can be detected simultaneously.
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PMID:Concurrent specific immunological detection of both primate and rodent forms of the guanine nucleotide binding protein G11 alpha following their coexpression. 803 5

The neural cell adhesion molecule (N-CAM), is expressed in definite spatiotemporal patterns during development. To identify factors that may influence place-dependent n-cam gene expression, we have studied the binding and activation of the n-cam promoter by Pax-8, a member of the Pax family of transcription factors. Pax-8 increased n-cam promoter activity 13.4-fold in cellular co-transfection experiments, and a short segment of the promoter (-143 to -15) mediated the response. This region of the n-cam promoter produced a DNA-protein complex when incubated with either extracts from COS-7 cells transfected with the Pax-8 expression vector or a Pax-8/GST fusion protein. Pax-8 bound to the n-cam promoter through two TGCTCC motifs (designated PBS-1 and PBS-2) that resemble paired domain binding sites. Mutation of PBS-1 and PBS-2 eliminated Pax-8 activation of the n-cam promoter. Transfection of N2A neuroblastoma cells with the Pax-8 expression vector resulted in a 5-fold increase in the transcription of the endogenous n-cam gene. The combined results suggest that Pax-8 activates transcription of the n-cam gene through binding of sequences resembling paired domain binding sites in the n-cam promoter. The data raise the possibility that the n-cam promoter may be regulated by other members of the Pax gene family.
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PMID:Binding and activation of the promoter for the neural cell adhesion molecule by Pax-8. 807 51

Two distinct cDNAs encoding bradykinin receptors (BKRs) were cloned from NG108-15 neuroblastoma-glioma hybrid cells. One was identical with rat uterus B2 BKR, whereas the other one (mBKR) had 91% amino acid homology to the rat B2 BKR and 82% homology to human B2 BKR. Southern blot analysis and genomic DNA cloning revealed that mBKR is derived from the mouse genome. The mBKR, expressed in Xenopus oocytes and COS-7 cells, produced functional BKRs that exhibited the properties of smooth muscle type B2 BKR. These results suggest that both the rat and mouse B2 BKRs of the smooth muscle type are expressed in NG108-15 cells.
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PMID:B2 bradykinin receptors in NG108-15 cells: cDNA cloning and functional expression. 816 39

We have isolated DNA clones encoding functional bradykinin receptors from human, rat, and mouse sources. Genomic bradykinin receptor clones have been isolated from mouse and human cosmid libraries and cDNA clones have been isolated from the human lung fibroblast cell line W138, from the neuroblastoma/glioma hybrid NG108-15, and from rat dorsal root ganglion cells. The receptor protein is encoded by an intronless region of the gene in both mouse and human. There is evidence of a splice acceptor site 8 bases upstream from the initiation codon in all three species. The function of the expressed receptor proteins from mouse, rat, and human was tested by electrophysiological assays after injection of cRNA into Xenopus laevis oocytes and also by binding assays with membranes from COS-7 cells transfected with cloned receptor-encoding DNA. The receptors from human and rat showed the pharmacological properties of B2 receptors in both expression systems when tested with a variety of bradykinin analogues, but receptors from mouse divided into two populations, one population with pharmacological properties of B1-like receptors and another, larger, population with properties of B2 receptors.
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PMID:Cloned murine bradykinin receptor exhibits a mixed B1 and B2 pharmacological selectivity. 839 91

A putative endogenous cannabinoid ligand, arachidonylethanolamide (termed "anandamide"), was isolated recently from porcine brain. Here we demonstrate that this compound is a specific cannabinoid agonist and exerts its action directly via the cannabinoid receptors. Anandamide specifically binds to membranes from cells transiently (COS) or stably (Chinese hamster ovary) transfected with an expression plasmid carrying the cannabinoid receptor DNA but not to membranes from control nontransfected cells. Moreover, anandamide inhibited the forskolin-stimulated adenylate cyclase in the transfected cells and in cells that naturally express cannabinoid receptors (N18TG2 neuroblastoma) but not in control nontransfected cells. As with exogenous cannabinoids, the inhibition by anandamide of the forskolin-stimulated adenylate cyclase was blocked by treatment with pertussis toxin. These data indicate that anandamide is an endogenous agonist that may serve as a genuine neurotransmitter for the cannabinoid receptor.
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PMID:Anandamide, a brain endogenous compound, interacts specifically with cannabinoid receptors and inhibits adenylate cyclase. 851 84

Human polyomavirus JC virus (JCV) is the causative agent of the demyelinating disorder progressive multifocal leukoencephalopathy (PML). In vivo the cellular tropism of JCV has been shown to be very narrow, and replication appears to be essentially restricted to oligodendrocytes. To investigate the detail cellular tropism of JCV, we employed transfection, microinjection and CAT assays using JCV permissive cells, and several non-permissive cell lines. IMR-32 (human neuroblastoma cells) was permissive for IMR-32 adapted JC virus. A431 (human epidermoid carcinoma) and COS-7 (a SV40 transformed African green monkey kidney cell line) were used as non-permissive cells. Employing infection it could be confirmed that the virus proliferated in IMR-32, but not in A431 and COS-7 cells as measured by immunofluorescence methods. However, after microinjection of IMR-32 adapted JCV it could be shown that virus could replicate not only in IMR-32 but also in COS-7 cells. Virus could not be replicated in A431 cells. Using CAT assays the regulatory region of IMR-32 adapted JCV was shown to be active in IMR-32 and COS-7 cells, but inactive in A431 cells. The result suggests that nuclear transcription factors are also determinant of JCV cell tropism in vivo in addition to specific cellular receptors.
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PMID:[Analysis of the cellular tropism of human polyoma JC virus (JCV)]. 854 82

The endoproteolytic processing of polypeptides at basic residues into distinct biologically active peptides is a common theme in prohormone maturation and processing. PTH-related protein (PTHrP) 1-173 contains eight putative endoproteolytic consensus sites that include a mono-arginyl (R37), paired basic (RR154-155), and related basic residue motifs (RLKR-4 to -1, RRR19-21, KKKK88-91, KRK96-98, KKKRR102-106, and KKKK147-150). To analyze the primary structural determinants involved in the posttranslational processing and secretion of PTHrP 1-173, we constructed a series of nonsense mutants that code for carboxy-terminal truncated polypeptides. Since the basic residue motifs are probable sites of endoproteolysis, these sites and the residues downstream were serially eliminated, thereby creating PTHrP 1-152, 1-146, 1-101, 1-95, 1-87, 1-36, and 1-18. The wild type PTHrP 1-173 and nonsense mutant constructs were transiently transfected into two cell lines, COS-1 and SK-N-BE(2). The COS-1 cells have a constitutive secretory pathway, whereas the neuroblastoma-derived BE-2 cells have, in addition, a regulated secretory pathway. PTHrP was measured in the conditioned media and cell extracts of the transfected cells with two peptide-specific RIAs. In COS-1 cells, PTHrP truncation mutants 1-152, 1-146, 1-101, 1-95, and 1-87 were present relative to wild type isoform 1-173, at 4.4-, 3-, 19-, 12-, and 57-fold excess, respectively; a similar pattern was also detected with BE-2 transfected cells, although the relative increases above the quantities of PTHrP 1-173 were not as dramatic. As the carboxy-terminal sequences were eliminated, the amount of total and secreted PTHrP increased, and the percentage found within the cell decreased. In COS-1 cells, 10.5% of the total PTHrP 1-173 was intracellular, whereas only 1% of the total PTHrP 1-87 was intracellular. In BE-2 cells, 54% of the total PTHrP 1-173 and only 9% of the total 1-87 mutant were intracellular. In COS-1 cells, a time course analysis demonstrated that PTHrP 1-87 and 1-95 were detectable in media 3 h after transfection, whereas 1-173 was barely detectable after 24 h. Our studies suggest that the carboxy-terminal sequence of PTHrP 1-173 is responsible for the intracellular degradation of this polypeptide, which may be the endogenous cellular mechanism that regulates the amount of processed and secreted PTHrP.
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PMID:Elimination of the carboxy-terminal sequences of parathyroid hormone-related protein 1-173 increases production and secretion of the truncated forms. 861 92

Sets of degenerate oligonucleotide primers synthesized on the basis of the best conserved regions of the chick brain P2Y/P2Y1 and the murine neuroblastoma P2U/P2Y2 receptors were used in polymerase chain reaction experiments on human genomic DNA. An amplified fragment of 712 base pairs was then used as a probe to screen a human genomic DNA library. Several clones were isolated and sequencing revealed an intronless 1122 base pair open reading frame. The corresponding amino acid sequence revealed 83% identity with the chick brain P2Y1 receptor and 34% with the murine neuroblastoma P2Y2 receptor. In COS-7 cells transfected with the coding sequence inserted into the pcDNA3 expression vector, 2-methylthioATP and ATP produced a strong stimulation of inositol phosphates, a typical response of a P2Y1 receptor. Northern blot analysis detected a 6.7 kilobase messenger RNA in most human tissues, the strongest signals being observed in prostate and ovary.
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PMID:Cloning and tissue distribution of the human P2Y1 receptor. 863 5

Recent molecular investigation revealed that two closely related structural genes encode distinct GDP-L-fucose:beta-D-galactoside 2-alpha-L-fucosyltransferases (alpha1,2-fucosyltransferases). Some human cancer cells or tissues may express an aberrant alpha1, 2-fucosyltransferase other than H- and Secretor-type alpha1, 2-fucosyltransferase. However, definite evidence of the existence of a third type of alpha1,2-fucosyltransferase has not been demonstrated. Here we report the molecular cloning of a third type of rabbit alpha1,2-fucosyltransferase (RFT-III) from a rabbit genomic DNA library. The DNA sequence included an open reading frame coding for 347 amino acids, and the deduced amino acid sequence of RFT-III showed 59 and 80% identity with those of the previously reported two types of rabbit alpha1,2-fucosyltransferase, RFT-I and RFT-II, respectively. COS-7 cells transfected with the RFT-III gene exhibited alpha1,2-fucosyltransferase activity toward phenyl-beta-Gal as a substrate. Neuro2a (a murine neuroblastoma cell line) cells transfected with the RFT-III gene expressed fucosyl GM1 (type 3 H) but not Ulex europaeus agglutinin-1 lectin reactive antigens (type 2 H). Kinetic studies revealed that RFT-III exhibits higher affinity to types 1 (Galbeta1, 3GlcNAc) and 3 (Galbeta1, 3GalNAc) than to type 2 (Galbeta1, 4GlcNAc) oligosaccharides, which suggests that RFT-III as well as RFT-II is a Secretor-type alpha1, 2-fucosyltransferase. RFT-III was expressed in the adult gastrointestinal tract. The RFT-I, -II, and -III genes were assigned within 90 kilobases on pulsed field gel electrophoresis analysis. These results constitute direct evidence that, at least in one mammalian species, three active alpha1,2-fucosyltransferases exist.
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PMID:Molecular cloning and expression of a third type of rabbit GDP-L-fucose:beta-D-galactoside 2-alpha-L-fucosyltransferase. 866 68


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