Molecular biology and genetics of prion diseases

1994 ◽  
Vol 343 (1306) ◽  
pp. 447-463 ◽  
Keyword(s):  
Nucleic Acid ◽  
De Novo ◽  
Prion Diseases ◽  
Spongiform Encephalopathy ◽  
Species Barrier ◽  
Prolonged Incubation ◽  
Brain Extracts ◽  
Jakob Disease ◽  
Spongiform Degeneration ◽  
The Difference

Scrapie was thought for m any years to be caused by a virus. Enriching fractions from Syrian hamster (SHa) brain for scrapie infectivity led to the discovery of the prion protein (PrP). To date, no scrapie-specific nucleic acid has been found. As well as scrapie, prion diseases include bovine spongiform encephalopathy (BSE) of cattle, as well as Creutzfeldt-Jakob disease (CJD) and Gerstmann-Sträussler-Scheinker syndrome (GSS) of humans. Transgenic (Tg) mice expressing both SHa and mouse (Mo) PrP genes were used to probe the molecular basis of the species barrier and the mechanism of scrapie prion replication. The prion inoculum was found to dictate which prions are synthesized de novo , even though the cells express both PrP genes. Discovery of mutations in the PrP genes of humans with GSS and familial CJD established that prion diseases are both genetic and infectious. Tg mice expressing MoPrP with the GSS point mutation spontaneously develop neurologic dysfunction, spongiform degeneration and astrocytic gliosis. Inoculation of brain extracts prepared from these Tg(MoPrP-P101L) mice produced neurodegeneration in many of the recipient animals after prolonged incubation times. These and other results suggest that prions are devoid of foreign nucleic acid and are thus different from viruses and viroids. Studies on the structure of PrP Sc and PrP c suggest that the difference is conformational. Whether one or more putative a-helices in PrP c are converted into (β-sheets during synthesis of PrP Sc is unknown. Distinct prion isolates or ‘strains’ exhibit different patterns of PrP Sc accumulation which are independent of incubation times. Whether variations in PrP Sc conformation are responsible for prion diversity remains to be established. Prion studies have given new insights into the etiologies of infectious, sporadic and inherited degenerative diseases.

scholarly journals Absence of Evidence for a Causal Link between Bovine Spongiform Encephalopathy Strain Variant L-BSE and Known Forms of Sporadic Creutzfeldt-Jakob Disease in Human PrP Transgenic Mice

2016 ◽  
Vol 90 (23) ◽  
pp. 10867-10874 ◽  
Author(s):  
Emilie Jaumain ◽  
Isabelle Quadrio ◽  
Laetitia Herzog ◽  
Fabienne Reine ◽  
Human Rezaei ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Bovine Spongiform Encephalopathy ◽  
Prion Diseases ◽  
Biological Properties ◽  
Causal Link ◽  
Cellular Prion Protein ◽  
Spongiform Encephalopathy ◽  
Species Barrier ◽  
Spongiform Encephalopathies ◽  
Jakob Disease

ABSTRACTPrions are proteinaceous pathogens responsible for subacute spongiform encephalopathies in animals and humans. The prions responsible for bovine spongiform encephalopathy (BSE) are zoonotic agents, causing variant Creutzfeldt-Jakob disease (CJD) in humans. The transfer of prions between species is limited by a species barrier, which is thought to reflect structural incompatibilities between the host cellular prion protein (PrPC) and the infecting pathological PrP assemblies (PrPSc) constituting the prion. A BSE strain variant, designated L-BSE and responsible for atypical, supposedly spontaneous forms of prion diseases in aged cattle, demonstrates zoonotic potential, as evidenced by its capacity to propagate more easily than classical BSE in transgenic mice expressing human PrPCand in nonhuman primates. In humanized mice, L-BSE propagates without any apparent species barrier and shares similar biochemical PrPScsignatures with the CJD subtype designated MM2-cortical, thus opening the possibility that certain CJD cases classified as sporadic may actually originate from L-type BSE cross-transmission. To address this issue, we compared the biological properties of L-BSE and those of a panel of CJD subtypes representative of the human prion strain diversity using standard strain-typing criteria in human PrP transgenic mice. We found no evidence that L-BSE causes a known form of sporadic CJD.IMPORTANCESince the quasi-extinction of classical BSE, atypical BSE forms are the sole BSE variants circulating in cattle worldwide. They are observed in rare cases of old cattle, making them difficult to detect. Extrapolation of our results suggests that L-BSE may propagate in humans as an unrecognized form of CJD, and we urge both the continued utilization of precautionary measures to eliminate these agents from the human food chain and active surveillance for CJD phenotypes in the general population.

Cellular factors important for the de novo formation of yeast prions

2008 ◽  
Vol 36 (5) ◽  
pp. 1083-1087 ◽  
Author(s):  
Mick Tuite ◽  
Klement Stojanovski ◽  
Frederique Ness ◽  
Gloria Merritt ◽  
Nadejda Koloteva-Levine
Keyword(s):  
De Novo ◽  
Prion Diseases ◽  
Underlying Mechanism ◽  
Structural Form ◽  
Yeast Saccharomyces Cerevisiae ◽  
Yeast Prions ◽  
Cellular Factors ◽  
Jakob Disease ◽  
Protein Rich ◽  
Cis And Trans

Prions represent an unusual structural form of a protein that is ‘infectious’. In mammals, prions are associated with fatal neurodegenerative diseases such as CJD (Creutzfeldt–Jakob disease), while in fungi they act as novel epigenetic regulators of phenotype. Even though most of the human prion diseases arise spontaneously, we still know remarkably little about how infectious prions form de novo. The [PSI+] prion of the yeast Saccharomyces cerevisiae provides a highly tractable model in which to explore the underlying mechanism of de novo prion formation, in particular identifying key cis- and trans-acting factors. Most significantly, the de novo formation of [PSI+] requires the presence of a second prion called [PIN+], which is typically the prion form of Rnq1p, a protein rich in glutamine and aspartic acid residues. The molecular mechanism by which the [PIN+] prion facilitates de novo [PSI+] formation is not fully established, but most probably involves some form of cross-seeding. A number of other cellular factors, in particular chaperones of the Hsp70 (heat-shock protein 70) family, are known to modify the frequency of de novo prion formation in yeast.

scholarly journals Prion diseases are efficiently transmitted by blood transfusion in sheep

Blood ◽  
2008 ◽  
Vol 112 (12) ◽  
pp. 4739-4745 ◽  
Author(s):  
Fiona Houston ◽  
Sandra McCutcheon ◽  
Wilfred Goldmann ◽  
Angela Chong ◽  
James Foster ◽  
...  
Keyword(s):  
Blood Transfusion ◽  
Prion Diseases ◽  
Clinical Signs ◽  
Control Measures ◽  
Spongiform Encephalopathy ◽  
Transmission Rates ◽  
High Transmission ◽  
Jakob Disease ◽  
Natural Scrapie ◽  
Iatrogenic Transmission

Abstract The emergence of variant Creutzfeld-Jakob disease, following on from the bovine spongiform encephalopathy (BSE) epidemic, led to concerns about the potential risk of iatrogenic transmission of disease by blood transfusion and the introduction of costly control measures to protect blood supplies. We previously reported preliminary data demonstrating the transmission of BSE and natural scrapie by blood transfusion in sheep. The final results of this experiment, reported here, give unexpectedly high transmission rates by transfusion of 36% for BSE and 43% for scrapie. A proportion of BSE-infected tranfusion recipients (3 of 8) survived for up to 7 years without showing clinical signs of disease. The majority of transmissions resulted from blood collected from donors at more than 50% of the estimated incubation period. The high transmission rates and relatively short and consistent incubation periods in clinically positive recipients suggest that infectivity titers in blood were substantial and/or that blood transfusion is an efficient method of transmission. This experiment has established the value of using sheep as a model for studying transmission of variant Creutzfeld-Jakob disease by blood products in humans.

scholarly journals Loss of PIKfyve drives the spongiform degeneration in prion diseases

2021 ◽  
Author(s):  
Asvin KK Lakkaraju ◽  
Karl Frontzek ◽  
Emina Lemes ◽  
Uli Herrmann ◽  
Marco Losa ◽  
...  
Keyword(s):  
Cultured Cells ◽  
Prion Diseases ◽  
Brain Slices ◽  
Prion Infection ◽  
Unfolded Protein ◽  
Phosphatidylinositol Kinase ◽  
Jakob Disease ◽  
Infected Cells ◽  
Spongiform Degeneration ◽  
Protein Response

Brain-matter vacuolation is a defining trait of all prion diseases, yet its cause is unknown. Here we report that prion infection and prion-mimetic antibodies deplete the phosphatidylinositol kinase PIKfyve in mouse brains, cultured cells, organotypic brain slices, and in brains of Creutzfeldt-Jakob Disease victims. We found that PIKfyve, an inositol kinase involved endolysosomal maturation, is acylated by zDHHC9 and zDHHC21, whose juxtavesicular topology is disturbed by prion infection, resulting in PIKfyve deacylation and destabilization. A protracted unfolded protein response (UPR), typical of prion diseases, also induced PIKfyve deacylation and degradation. Conversely, UPR antagonists restored PIKfyve levels in prion-infected cells. Overexpression of zDHHC9 and zDHHC21, administration of the antiprion polythiophene LIN5044, or supplementation with the PIKfyve reaction product PI(3,5)P2, suppressed prion-induced vacuolation. Thus, PIKfyve emerges as a central mediator of vacuolation and neurotoxicity in prion diseases.

scholarly journals Exposure Risk of Chronic Wasting Disease in Humans

Viruses ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1454
Author(s):  
Satish K. Nemani ◽  
Jennifer L. Myskiw ◽  
Lise Lamoureux ◽  
Stephanie A. Booth ◽  
Valerie L. Sim
Keyword(s):  
Chronic Wasting Disease ◽  
Prion Diseases ◽  
Causal Link ◽  
In Vivo Studies ◽  
Spongiform Encephalopathy ◽  
Strain Typing ◽  
Species Barrier ◽  
Wasting Disease

The majority of human prion diseases are sporadic, but acquired disease can occur, as seen with variant Creutzfeldt–Jakob disease (vCJD) following consumption of bovine spongiform encephalopathy (BSE). With increasing rates of cervid chronic wasting disease (CWD), there is concern that a new form of human prion disease may arise. Currently, there is no evidence of transmission of CWD to humans, suggesting the presence of a strong species barrier; however, in vitro and in vivo studies on the zoonotic potential of CWD have yielded mixed results. The emergence of different CWD strains is also concerning, as different strains can have different abilities to cross species barriers. Given that venison consumption is common in areas where CWD rates are on the rise, increased rates of human exposure are inevitable. If CWD was to infect humans, it is unclear how it would present clinically; in vCJD, it was strain-typing of vCJD prions that proved the causal link to BSE. Therefore, the best way to screen for CWD in humans is to have thorough strain-typing of harvested cervids and human CJD cases so that we will be in a position to detect atypical strains or strain shifts within the human CJD population.

Human Prion Diseases

2013 ◽  
pp. 149-160
Author(s):  
James W. Ironside ◽  
Matthew P. Frosch ◽  
Bernardino Ghetti
Keyword(s):  
Prion Diseases ◽  
Neuronal Loss ◽  
Transmissible Spongiform Encephalopathies ◽  
Spongiform Encephalopathy ◽  
Pituitary Hormone ◽  
Human Pituitary ◽  
Spongiform Encephalopathies ◽  
Jakob Disease ◽  
Prnp Codon ◽  
Codon 129

This chapter describes and illustrates the neuropathology of prion diseases, also known as transmissible spongiform encephalopathies. These diseases are characterized pathologically by varying combinations of spongiform change, neuronal loss, reactive gliosis, and prion protein (PrP) deposition. The morphologic pattern depends on the etiology of the disease and the genotype of the patient. Different clinicopathological phenotypes of sporadic Creutzfeldt-Jakob disease (CJD) have been described depending on the PRNP codon 129 genotype and the PrP isotype. A novel form known as variably protease-sensitive prionopathy has been recently identified. Familial prion diseases include familial CJD, Gerstmann-Sträussler-Scheinker disease, and fatal familial insomnia. Over 40 different PRNP mutations have been identified. Acquired prion diseases include Kuru; iatrogenic CJD, particularly in recipients of contaminated human pituitary hormone, and variant CJD, which seems closely related to bovine spongiform encephalopathy.

scholarly journals Complex proteinopathy with accumulations of prion protein, hyperphosphorylated tau, α-synuclein and ubiquitin in experimental bovine spongiform encephalopathy of monkeys

2014 ◽  
Vol 95 (7) ◽  
pp. 1612-1618 ◽  
Author(s):  
Pedro Piccardo ◽  
Juraj Cervenak ◽  
Ming Bu ◽  
Lindsay Miller ◽  
David M. Asher
Keyword(s):  
Neurodegenerative Diseases ◽  
Bovine Spongiform Encephalopathy ◽  
Prion Protein ◽  
Common Mechanism ◽  
Spongiform Encephalopathy ◽  
Hyperphosphorylated Tau ◽  
Jakob Disease ◽  
Spongiform Degeneration ◽  
Bovine Spongiform Encephalopathy Agent ◽  
Classical Bovine Spongiform Encephalopathy

Proteins aggregate in several slowly progressive neurodegenerative diseases called ‘proteinopathies’. Studies with cell cultures and transgenic mice overexpressing mutated proteins suggested that aggregates of one protein induced misfolding and aggregation of other proteins as well – a possible common mechanism for some neurodegenerative diseases. However, most proteinopathies are ‘sporadic’, without gene mutation or overexpression. Thus, proteinopathies in WT animals genetically close to humans might be informative. Squirrel monkeys infected with the classical bovine spongiform encephalopathy agent developed an encephalopathy resembling variant Creutzfeldt–Jakob disease with accumulations not only of abnormal prion protein (PrPTSE), but also three other proteins: hyperphosphorylated tau (p-tau), α-synuclein and ubiquitin; β-amyloid protein (Aβ) did not accumulate. Severity of brain lesions correlated with spongiform degeneration. No amyloid was detected. These results suggested that PrPTSE enhanced formation of p-tau and aggregation of α-synuclein and ubiquitin, but not Aβ, providing a new experimental model for neurodegenerative diseases associated with complex proteinopathies.

scholarly journals Prion Protein Devoid of the Octapeptide Repeat Region Delays Bovine Spongiform Encephalopathy Pathogenesis in Mice

2017 ◽  
Vol 92 (1) ◽  
Author(s):  
Hideyuki Hara ◽  
Hironori Miyata ◽  
Nandita Rani Das ◽  
Junji Chida ◽  
Tatenobu Yoshimochi ◽  
...  
Keyword(s):  
Bovine Spongiform Encephalopathy ◽  
Prion Protein ◽  
Prion Diseases ◽  
Spongiform Encephalopathy ◽  
Wild Type ◽  
Jakob Disease ◽  
Function Relationship ◽  
Different Strains ◽  
Conformational Conversion

ABSTRACTConformational conversion of the cellular isoform of prion protein, PrPC, into the abnormally folded, amyloidogenic isoform, PrPSc, is a key pathogenic event in prion diseases, including Creutzfeldt-Jakob disease in humans and scrapie and bovine spongiform encephalopathy (BSE) in animals. We previously reported that the octapeptide repeat (OR) region could be dispensable for converting PrPCinto PrPScafter infection with RML prions. We demonstrated that mice transgenically expressing mouse PrP with deletion of the OR region on the PrP knockout background, designated Tg(PrPΔOR)/Prnp0/0mice, did not show reduced susceptibility to RML scrapie prions, with abundant accumulation of PrPScΔOR in their brains. We show here that Tg(PrPΔOR)/Prnp0/0mice were highly resistant to BSE prions, developing the disease with markedly elongated incubation times after infection with BSE prions. The conversion of PrPΔOR into PrPScΔOR was markedly delayed in their brains. These results suggest that the OR region may have a crucial role in the conversion of PrPCinto PrPScafter infection with BSE prions. However, Tg(PrPΔOR)/Prnp0/0mice remained susceptible to RML and 22L scrapie prions, developing the disease without elongated incubation times after infection with RML and 22L prions. PrPScΔOR accumulated only slightly less in the brains of RML- or 22L-infected Tg(PrPΔOR)/Prnp0/0mice than PrPScin control wild-type mice. Taken together, these results indicate that the OR region of PrPCcould play a differential role in the pathogenesis of BSE prions and RML or 22L scrapie prions.IMPORTANCEStructure-function relationship studies of PrPCconformational conversion into PrPScare worthwhile to understand the mechanism of the conversion of PrPCinto PrPSc. We show here that, by inoculating Tg(PrPΔOR)/Prnp0/0mice with the three different strains of RML, 22L, and BSE prions, the OR region could play a differential role in the conversion of PrPCinto PrPScafter infection with RML or 22L scrapie prions and BSE prions. PrPΔOR was efficiently converted into PrPScΔOR after infection with RML and 22L prions. However, the conversion of PrPΔOR into PrPScΔOR was markedly delayed after infection with BSE prions. Further investigation into the role of the OR region in the conversion of PrPCinto PrPScafter infection with BSE prions might be helpful for understanding the pathogenesis of BSE prions.

Biology of the prion gene complex

2001 ◽  
Vol 79 (5) ◽  
pp. 613-628 ◽  
Author(s):  
Peter Mastrangelo ◽  
David Westaway
Keyword(s):  
Prion Protein ◽  
Protein Function ◽  
Prion Diseases ◽  
Mammalian Species ◽  
Prnp Gene ◽  
Spongiform Encephalopathy ◽  
Missense Mutations ◽  
Point Of Entry ◽  
Major Structural Component ◽  
Jakob Disease

The prion protein gene Prnp encodes PrPSc, the major structural component of prions, infectious pathogens causing a number of disorders including scrapie and bovine spongiform encephalopathy (BSE). Missense mutations in the human Prnp gene, PRNP, cause inherited prion diseases such as familial Creutzfeldt–Jakob Disease. In uninfected animals, Prnp encodes a GPI-anchored protein denoted PrPC, and in prion infections, PrPCis converted to PrPScby templated refolding. Although Prnp is conserved in mammalian species, attempts to verify interactions of putative PrP-binding proteins by genetic means have proven frustrating in that two independent lines of Prnp gene ablated mice (Prnp0/0mice: ZrchI and Npu) lacking PrPCremain healthy throughout development. This indicates that PrPCserves a function that is not apparent in a laboratory setting or that other molecules have overlapping functions. Shuttling or sequestration of synaptic Cu(II) via binding to N-terminal octapeptide residues and (or) signal transduction involving the fyn kinase are possibilities currently under consideration. A new point of entry into the issue of prion protein function has emerged from identification of a paralog, Prnd, with 25% coding sequence identity to Prnp. Prnd lies downstream of Prnp and encodes the Dpl protein. Like PrPC, Dpl is presented on the cell surface via a GPI anchor and has three α-helices: however, it lacks the conformationally plastic and octapeptide repeat domains present in its well-known relative. Interestingly, Dpl is overexpressed in two other lines of Prnp0/0mice (Ngsk and Rcm0) via intergenic splicing events. These lines of Prnp0/0mice exhibit ataxia and apoptosis of cerebellar cells, indicating that ectopic synthesis of Dpl protein is toxic to CNS neurons: this inference has now been confirmed by the construction of transgenic mice expressing Dpl under the direct control of the PrP promoter. Remarkably, Dpl-programmed ataxia is rescued by wt Prnp transgenes. The interaction between the Prnp and Prnd genes in mouse cerebellar neurons may have a physical correlate in competition between Dpl and PrPCwithin a common biochemical pathway that, when misregulated, leads to apoptosis.Key words: spongiform encephalopathy, neurodegenerative disease, paralogs, scrapie, CJD.

scholarly journals Creutzfeldt-Jakob disease surveillance in Australia: update to 31 December 2019

2020 ◽  
Vol 44 ◽  
Author(s):  
Christiane Stehmann ◽  
Matteo Senesi ◽  
Shannon Sarros ◽  
Amelia McGlade ◽  
Marion Simpson ◽  
...  
Keyword(s):  
Prion Disease ◽  
Disease Surveillance ◽  
Prion Diseases ◽  
Transmissible Spongiform Encephalopathy ◽  
Annual Number ◽  
Spongiform Encephalopathy ◽  
Human Prion Disease ◽  
Prospective Surveillance ◽  
Jakob Disease ◽  
Neuropathological Examination

Nationwide surveillance of Creutzfeldt-Jakob disease and other human prion diseases is performed by the Australian National Creutzfeldt-Jakob Disease Registry (ANCJDR). National surveillance encompasses the period since 1 January 1970, with prospective surveillance occurring from 1 October 1993. Over this prospective surveillance period, considerable developments have occurred in pre-mortem diagnostics; in the delineation of new disease subtypes; and in a heightened awareness of prion diseases in healthcare settings. Surveillance practices of the ANCJDR have evolved and adapted accordingly. This report summarises the activities of the ANCJDR during 2019. Since the ANCJDR began offering diagnostic cerebrospinal fluid (CSF) 14-3-3 protein testing in Australia in September 1997, the annual number of referrals has steadily increased. In 2019, 513 domestic CSF specimens were referred for 14-3-3 protein testing and 85 persons with suspected human prion disease were formally added to the national register. As of 31 December 2019, just under half (42 cases) of the 85 suspect case notifications remain classified as ‘incomplete’; 16 cases were excluded through either detailed clinical follow-up (3 cases) or neuropathological examination (13 cases); 20 cases were classified as ‘definite’ and seven as ‘probable’ prion disease. For 2019, sixty-three percent of all suspected human prion disease related deaths in Australia underwent neuropathological examination. No cases of variant or iatrogenic CJD were identified. Two possibly causal novel prion protein gene (PRNP) sequence variations were identified. Keywords: Creutzfeldt-Jakob disease, prion disease, transmissible spongiform encephalopathy, disease surveillance

Sign in / Sign up

Export Citation Format

Share Document