Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0917801 (insomnia)
 10,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To provide an in vitro system that allows inducible or conditional overexpression of human prion protein (PrP), we have established a tetracycline (Tc)-regulated system in murine 3T3 L1 fibroblast cells. A replacement-type gene targeting vector cassette was constructed to express the human fatal familial insomnia (FFI) prion protein gene (PRNP) under control of a Tc-responsive element. Following stable integration of the vector into 3T3 Tet-Off cells, we have isolated and characterised six 3T3 L1 pTet-Off FFI clones. These clones were analysed by PCR and their expression level was determined by Western blot using species specific monoclonal antibodies (anti-mouse and human 3B5, 4F2, 12F10, 11C6, 8G8, and 14D3; anti-mouse l3). Addition of the antibiotic Tc to the culture medium turned off expression of human PrP. This supression was repeatedly reversible. However, no significant transcriptional leakiness of repressed PminCMV promoter was observed. In the absence of Tc, expression of human PrP was induced 10- to 20-fold as estimated from densitometric analyses. PrP was analysed by Proteinase K (PK) digestions and found to be PK sensitive. Subcellular fractionation revealed that PrP was located mainly in the cytoplasmic membrane fraction. Furthermore, we partially purified PrP by PrP-specific copper-binding. After immobilised metal affinity chromatography, majority of PrP showed a molecular weight consistent with non-glycosylated PrP. These clones offer a new tool to facilitate the investigation of PrP interaction with potential cellular ligands and PrP ex vivo propagation.
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PMID:Tetracycline-regulated highly inducible expression of the human prion protein in murine 3T3 cells. 1559 55

We compared clinical data from two related Chinese patients with fatal familial insomnia (FFI) and collected information about their pedigree. The clinical features in the two cases were similar and included initial progressive insomnia and sympathetic activation, which persisted throughout the clinical course. A total of 135 members of this family, across seven generations, were retrospectively investigated. Eleven family members, including the two FFI cases, were found to have died with similar neurological problems. Analysis of PRNP in 32 family members revealed eleven carrying the D178N allele, including the two FFI patients. Spongiform degeneration in brains was not found, but gliosis was obvious in the thalamus of the two cases at postmortem. Proteinase K-resistant prion protein (PrP) was not found in proband's brain by immunohistochemistry, but observed in some areas of brain for both cases by PrP-specific Western blot. Investigation of the pedigree has led to the identification of an additional 9 family members who had similar clinical symptoms and 9 currently healthy individuals with the D178N mutation.
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PMID:Clinical, histopathological and genetic studies in a family with fatal familial insomnia. 2009 9

Inherited human prion diseases, such as fatal familial insomnia (FFI) and familial Creutzfeldt-Jakob disease (fCJD), are associated with autosomal dominant mutations in the human prion protein gene PRNP and accumulation of PrPSc, an abnormal isomer of the normal host protein PrPC, in the brain of affected individuals. PrPSc is the principal component of the transmissible neurotoxic prion agent. It is important to identify molecular pathways and cellular processes that regulate prion formation and prion-induced neurotoxicity. This will allow identification of possible therapeutic interventions for individuals with, or at risk from, genetic human prion disease. Increasingly, Drosophila has been used to model human neurodegenerative disease. An important unanswered question is whether genetic prion disease with concomitant spontaneous prion formation can be modelled in Drosophila We have used pUAST/PhiC31-mediated site-directed mutagenesis to generate Drosophila transgenic for murine or hamster PrP (prion protein) that carry single-codon mutations associated with genetic human prion disease. Mouse or hamster PrP harbouring an FFI (D178N) or fCJD (E200K) mutation showed mild Proteinase K resistance when expressed in Drosophila Adult Drosophila transgenic for FFI or fCJD variants of mouse or hamster PrP displayed a spontaneous decline in locomotor ability that increased in severity as the flies aged. Significantly, this mutant PrP-mediated neurotoxic fly phenotype was transferable to recipient Drosophila that expressed the wild-type form of the transgene. Collectively, our novel data are indicative of the spontaneous formation of a PrP-dependent neurotoxic phenotype in FFI- or CJD-PrP transgenic Drosophila and show that inherited human prion disease can be modelled in this invertebrate host.
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PMID:Genetic human prion disease modelled in PrP transgenic Drosophila. 2881 78