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1.
Synthetic mammalian prions 总被引：1，自引：0，他引：1
Legname G Baskakov IV Nguyen HO Riesner D Cohen FE DeArmond SJ Prusiner SB 《Science (New York, N.Y.)》2004,305(5684):673-676
Recombinant mouse prion protein (recMoPrP) produced in Escherichia coli was polymerized into amyloid fibrils that represent a subset of beta sheet-rich structures. Fibrils consisting of recMoPrP(89-230) were inoculated intracerebrally into transgenic (Tg) mice expressing MoPrP(89-231). The mice developed neurologic dysfunction between 380 and 660 days after inoculation. Brain extracts showed protease-resistant PrP by Western blotting; these extracts transmitted disease to wild-type FVB mice and Tg mice overexpressing PrP, with incubation times of 150 and 90 days, respectively. Neuropathological findings suggest that a novel prion strain was created. Our results provide compelling evidence that prions are infectious proteins. 相似文献
2.
Angers RC Browning SR Seward TS Sigurdson CJ Miller MW Hoover EA Telling GC 《Science (New York, N.Y.)》2006,311(5764):1117
The emergence of chronic wasting disease (CWD) in deer and elk in an increasingly wide geographic area, as well as the interspecies transmission of bovine spongiform encephalopathy to humans in the form of variant Creutzfeldt Jakob disease, have raised concerns about the zoonotic potential of CWD. Because meat consumption is the most likely means of exposure, it is important to determine whether skeletal muscle of diseased cervids contains prion infectivity. Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure. 相似文献
3.
Béringue V Herzog L Jaumain E Reine F Sibille P Le Dur A Vilotte JL Laude H 《Science (New York, N.Y.)》2012,335(6067):472-475
Prions are infectious pathogens essentially composed of PrP(Sc), an abnormally folded form of the host-encoded prion protein PrP(C). Constrained steric interactions between PrP(Sc) and PrP(C) are thought to provide prions with species specificity and to control cross-species transmission into other host populations, including humans. We compared the ability of brain and lymphoid tissues from ovine and human PrP transgenic mice to replicate foreign, inefficiently transmitted prions. Lymphoid tissue was consistently more permissive than the brain to prions such as those causing chronic wasting disease and bovine spongiform encephalopathy. Furthermore, when the transmission barrier was overcome through strain shifting in the brain, a distinct agent propagated in the spleen, which retained the ability to infect the original host. Thus, prion cross-species transmission efficacy can exhibit a marked tissue dependence. 相似文献
4.
Chesebro B Trifilo M Race R Meade-White K Teng C LaCasse R Raymond L Favara C Baron G Priola S Caughey B Masliah E Oldstone M 《Science (New York, N.Y.)》2005,308(5727):1435-1439
In prion and Alzheimer's diseases, the roles played by amyloid versus nonamyloid deposits in brain damage remain unresolved. In scrapie-infected transgenic mice expressing prion protein (PrP) lacking the glycosylphosphatidylinositol (GPI) membrane anchor, abnormal protease-resistant PrPres was deposited as amyloid plaques, rather than the usual nonamyloid form of PrPres. Although PrPres amyloid plaques induced brain damage reminiscent of Alzheimer's disease, clinical manifestations were minimal. In contrast, combined expression of anchorless and wild-type PrP produced accelerated clinical scrapie. Thus, the PrP GPI anchor may play a role in the pathogenesis of prion diseases. 相似文献
5.
Meyer-Luehmann M Coomaraswamy J Bolmont T Kaeser S Schaefer C Kilger E Neuenschwander A Abramowski D Frey P Jaton AL Vigouret JM Paganetti P Walsh DM Mathews PM Ghiso J Staufenbiel M Walker LC Jucker M 《Science (New York, N.Y.)》2006,313(5794):1781-1784
Protein aggregation is an established pathogenic mechanism in Alzheimer's disease, but little is known about the initiation of this process in vivo. Intracerebral injection of dilute, amyloid-beta (Abeta)-containing brain extracts from humans with Alzheimer's disease or beta-amyloid precursor protein (APP) transgenic mice induced cerebral beta-amyloidosis and associated pathology in APP transgenic mice in a time- and concentration-dependent manner. The seeding activity of brain extracts was reduced or abolished by Abeta immunodepletion, protein denaturation, or by Abeta immunization of the host. The phenotype of the exogenously induced amyloidosis depended on both the host and the source of the agent, suggesting the existence of polymorphic Abeta strains with varying biological activities reminiscent of prion strains. 相似文献
6.
Wadsworth JD Asante EA Desbruslais M Linehan JM Joiner S Gowland I Welch J Stone L Lloyd SE Hill AF Brandner S Collinge J 《Science (New York, N.Y.)》2004,306(5702):1793-1796
Variant Creutzfeldt-Jakob disease (vCJD) is a unique and highly distinctive clinicopathological and molecular phenotype of human prion disease associated with infection with bovine spongiform encephalopathy (BSE)-like prions. Here, we found that generation of this phenotype in transgenic mice required expression of human prion protein (PrP) with methionine 129. Expression of human PrP with valine 129 resulted in a distinct phenotype and, remarkably, persistence of a barrier to transmission of BSE-derived prions on subpassage. Polymorphic residue 129 of human PrP dictated propagation of distinct prion strains after BSE prion infection. Thus, primary and secondary human infection with BSE-derived prions may result in sporadic CJD-like or novel phenotypes in addition to vCJD, depending on the genotype of the prion source and the recipient. 相似文献
7.
朊病毒为一不含核酸的蛋白感染因子，能引起哺乳动物中枢神经组织病变，它是由正常形式的蛋白（PrPC)错误折叠成致病蛋白（PrPSc)而组成的，两种结构异型蛋白来源于同一基因，朊病毒抚养殖是通过PrPC构象转变成为PrPSc而实现的。 相似文献
8.
Mathiason CK Powers JG Dahmes SJ Osborn DA Miller KV Warren RJ Mason GL Hays SA Hayes-Klug J Seelig DM Wild MA Wolfe LL Spraker TR Miller MW Sigurdson CJ Telling GC Hoover EA 《Science (New York, N.Y.)》2006,314(5796):133-136
A critical concern in the transmission of prion diseases, including chronic wasting disease (CWD) of cervids, is the potential presence of prions in body fluids. To address this issue directly, we exposed cohorts of CWD-na?ve deer to saliva, blood, or urine and feces from CWD-positive deer. We found infectious prions capable of transmitting CWD in saliva (by the oral route) and in blood (by transfusion). The results help to explain the facile transmission of CWD among cervids and prompt caution concerning contact with body fluids in prion infections. 相似文献
9.
Changes in prion protein (PrP) folding are associated with fatal neurodegenerative disorders, but the neurotoxic species is unknown. Like other proteins that traffic through the endoplasmic reticulum, misfolded PrP is retrograde transported to the cytosol for degradation by proteasomes. Accumulation of even small amounts of cytosolic PrP was strongly neurotoxic in cultured cells and transgenic mice. Mice developed normally but acquired severe ataxia, with cerebellar degeneration and gliosis. This establishes a mechanism for converting wild-type PrP to a highly neurotoxic species that is distinct from the self-propagating PrP(Sc) isoform and suggests a potential common framework for seemingly diverse PrP neurodegenerative disorders. 相似文献
10.
Starting with purified, bacterially produced protein, we have created a [PSI(+)]-inducing agent based on an altered (prion) conformation of the yeast Sup35 protein. After converting Sup35p to its prion conformation in vitro, we introduced it into the cytoplasm of living yeast using a liposome transformation protocol. Introduction of substoichiometric quantities of converted Sup35p greatly increased the rate of appearance of the well-characterized epigenetic factor [PSI+], which results from self-propagating aggregates of cellular Sup35p. Thus, as predicted by the prion hypothesis, proteins can act as infectious agents by causing self-propagating conformational changes. 相似文献
11.
Heppner FL Musahl C Arrighi I Klein MA Rülicke T Oesch B Zinkernagel RM Kalinke U Aguzzi A 《Science (New York, N.Y.)》2001,294(5540):178-182
Variant Creutzfeldt-Jakob disease and bovine spongiform encephalopathy are initiated by extracerebral exposure to prions. Although prion transmission from extracerebral sites to the brain represents a potential target for prophylaxis, attempts at vaccination have been limited by the poor immunogenicity of prion proteins. To circumvent this, we expressed an anti-prion protein (anti-PrP) mu chain in Prnp(o/o) mice. Transgenic mice developed sustained anti-PrP titers, which were not suppressed by introduction of Prnp+ alleles. Transgene expression prevented pathogenesis of prions introduced by intraperitoneal injection in the spleen and brain. Expression of endogenous PrP (PrP(C)) in the spleen and brain was unaffected, suggesting that immunity was responsible for protection. This indicates the feasibility of immunological inhibition of prion disease in vivo. 相似文献
12.
Mallucci G Dickinson A Linehan J Klöhn PC Brandner S Collinge J 《Science (New York, N.Y.)》2003,302(5646):871-874
The mechanisms involved in prion neurotoxicity are unclear, and therapies preventing accumulation of PrPSc, the disease-associated form of prion protein (PrP), do not significantly prolong survival in mice with central nervous system prion infection. We found that depleting endogenous neuronal PrPc in mice with established neuroinvasive prion infection reversed early spongiform change and prevented neuronal loss and progression to clinical disease. This occurred despite the accumulation of extraneuronal PrPSc to levels seen in terminally ill wild-type animals. Thus, the propagation of nonneuronal PrPSc is not pathogenic, but arresting the continued conversion of PrPc to PrPSc within neurons during scrapie infection prevents prion neurotoxicity. 相似文献
13.
K K Hsiao M Scott D Foster D F Groth S J DeArmond S B Prusiner 《Science (New York, N.Y.)》1990,250(4987):1587-1590
Transgenic mice were created to assess genetic linkage between Gerstmann-Str?ussler-Scheinker syndrome and a leucine substitution at codon 102 of the human prion protein gene. Spontaneous neurologic disease with spongiform degeneration and gliosis similar to that in mouse scrapie developed at a mean age of 166 days in 35 mice expressing mouse prion protein with the leucine substitution. Thus, many of the clinical and pathological features of Gerstmann-Str?ussler-Scheinker syndrome are reproduced in transgenic mice containing a prion protein with a single amino acid substitution, illustrating that a neurodegenerative process similar to a human disease can be genetically modeled in animals. 相似文献
14.
以原核表达的GST-BoPrP(23～242)融合蛋白为抗原,免疫BALB/C小鼠,制备抗牦牛朊蛋白的特异性抗血清。经Western blotting和间接ELISA鉴定,该抗血清可与牦牛重组成熟PrP(23～242)和牛脑组织提取物发生反应,蛋白酶K消化各抗原可消除免疫反应,但不与GST蛋白和E.coli BL21(DE3)的菌体蛋白发生反应,表明该抗血清为抗牦牛重组成熟PrP(23～242)的抗血清,其效价高达1∶12800,并能识别黄牛脑组织中的天然朊蛋白。原核表达的GST-BoPrP(23～242)融合蛋白能有效地刺激免疫动物产生PrP特异性抗体,所制备的抗血清可适用于天然朊蛋白的检测。 相似文献
15.
Klöhn PC Farmer M Linehan JM O'Malley C Fernandez de Marco M Taylor W Farrow M Khalili-Shirazi A Brandner S Collinge J 《Science (New York, N.Y.)》2012,335(6064):52
Intraperitoneal administration of ICSM18 and 35, monoclonal antibodies against prion protein (PrP), has been shown to significantly delay the onset of prion disease in mice, and humanized versions are candidate therapeutics for prion and Alzheimer's diseases. However, a previous report of severe and widespread apoptosis after intracerebral injection of anti-PrP monoclonal antibodies raised concerns about such therapy and led to an influential model of prion neurotoxicity via cross-linking of cell surface PrP by disease-related PrP aggregates. In extensive studies including ICSM18 and 35, fully humanized ICSM18, and the previously reported proapoptotic antibodies, we found no evidence of apoptosis, thereby questioning this model of prion neurotoxicity. 相似文献
16.
构建了绵羊朊蛋白的原核表达载体,获得了高纯度的融合表达蛋白。并在热力学因素的作用下,研究了重组绵羊朊蛋白的构象转化。以基因型为ARQ/ARQ蒙古绵羊的血液DNA为模板,利用DNA重组技术,将绵羊朊蛋白正常成熟蛋白基因OvPrP插入表达载体pET30a,在大肠杆菌BL2l(DE3)中高效表达,获得的表达产物以包涵体形式存在,并对其进行纯化和复性。超滤浓缩后浓度约为0.5 mg/mL的OvPrP97-234,进行热力学处理,利用远紫外线圆二色谱(CD)分析热力学处理前、后蛋白的二级结构的变化,同时,对热力学处理前、后的蛋白进行了蛋白酶K抗性的检测,并对其高级结构进行了预测。结果表明:获得的表达产物经SDS-PAGE分析可见分子量为16kD的蛋白条带,Western-blotting的鉴定证实了所获得的蛋白是特异性的朊蛋白。经Jascow32软件分析,测得天然构象的OvPrP97-234的二级结构含量为:α螺旋为28.8%、β折叠为0%、转角和无规卷曲为71.1%,无蛋白酶K的抗性。经过热力学处理之后,OvPrP97-234的二级结构含量为:α螺旋为19.3%,β折叠为36.9%,转角和无规卷曲为43.8%,有一定... 相似文献
17.
Heikenwalder M Zeller N Seeger H Prinz M Klöhn PC Schwarz P Ruddle NH Weissmann C Aguzzi A 《Science (New York, N.Y.)》2005,307(5712):1107-1110
Prions typically accumulate in nervous and lymphoid tissues. Because proinflammatory cytokines and immune cells are required for lymphoid prion replication, we tested whether inflammatory conditions affect prion pathogenesis. We administered prions to mice with five inflammatory diseases of the kidney, pancreas, or liver. In all cases, chronic lymphocytic inflammation enabled prion accumulation in otherwise prion-free organs. Inflammatory foci consistently correlated with lymphotoxin up-regulation and ectopic induction of FDC-M1+ cells expressing the normal cellular prion protein PrPC. By contrast, inflamed organs of mice lacking lymphotoxin-alpha or its receptor did not accumulate the abnormal isoform PrPSc, nor did they display infectivity upon prion inoculation. By expanding the tissue distribution of prions, chronic inflammatory conditions may act as modifiers of natural and iatrogenic prion transmission. 相似文献
18.
制备转基因小鼠特有的DIG标记探针，应用染色体荧光原位杂交（FISH）技术，对转基因小鼠外周血细胞的遗传性状进行分析，检测其合子类型，以挑选纯合子小鼠用于保种。结果杂合型小鼠61％的细胞有一个荧光信号，而纯合型小鼠约24％的细胞有两个荧光信号，48％的细胞有一个荧光信号，野生型小鼠无荧光信号。因此染色体荧光原位杂交技术可作为检测转基因小鼠遗传特性的一种方法。 相似文献
19.
Full-length poliovirus complementary DNA (cDNA) was synthesized by assembling oligonucleotides of plus and minus strand polarity. The synthetic poliovirus cDNA was transcribed by RNA polymerase into viral RNA, which translated and replicated in a cell-free extract, resulting in the de novo synthesis of infectious poliovirus. Experiments in tissue culture using neutralizing antibodies and CD155 receptor-specific antibodies and neurovirulence tests in CD155 transgenic mice confirmed that the synthetic virus had biochemical and pathogenic characteristics of poliovirus. Our results show that it is possible to synthesize an infectious agent by in vitro chemical-biochemical means solely by following instructions from a written sequence. 相似文献
20.
通过考查铜离子在朊病毒疾病发病过程中的作用，将有助于阐明朊病毒形成及发病机制以及重金属铜离子对朊病毒发病过程的影响，为进一步对朊病毒疾病的防治提供重要依据。实验运用采用转PrP基因线虫模型来研究朊蛋白与铜离子的相互作用。结果表明，线虫暴露于10^-3mol·L^-1铜离子浓度条件下，其对食物敏感性会下降，生命周期会减短，产卵数会减少；当线虫暴露于10^-4mol·L-1铜离子浓度条件下，会减少以上三种影响；当线虫暴露于10^-6mol·L-1铜离子浓度条件下，对线虫几乎没有影响。研究数据显示，在有高浓度铜离子影响情况下，转入朊蛋白102位点突变（dat-1-PrP102Mut）（w102）的线虫比转入朊蛋白（dat-1-PrPwt）（w101）的线虫损伤更严重，转入朊蛋白（W101）的线虫比野生型线虫（N2）损伤更严重。 相似文献