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1

PrionHome: A Database of Prions and Other Sequences Relevant to Prion Phenomena  

PubMed Central

Prions are units of propagation of an altered state of a protein or proteins; prions can propagate from organism to organism, through cooption of other protein copies. Prions contain no necessary nucleic acids, and are important both as both pathogenic agents, and as a potential force in epigenetic phenomena. The original prions were derived from a misfolded form of the mammalian Prion Protein PrP. Infection by these prions causes neurodegenerative diseases. Other prions cause non-Mendelian inheritance in budding yeast, and sometimes act as diseases of yeast. We report the bioinformatic construction of the PrionHome, a database of >2000 prion-related sequences. The data was collated from various public and private resources and filtered for redundancy. The data was then processed according to a transparent classification system of prionogenic sequences (i.e., sequences that can make prions), prionoids (i.e., proteins that propagate like prions between individual cells), and other prion-related phenomena. There are eight PrionHome classifications for sequences. The first four classifications are derived from experimental observations: prionogenic sequences, prionoids, other prion-related phenomena, and prion interactors. The second four classifications are derived from sequence analysis: orthologs, paralogs, pseudogenes, and candidate-prionogenic sequences. Database entries list: supporting information for PrionHome classifications, prion-determinant areas (where relevant), and disordered and compositionally-biased regions. Also included are literature references for the PrionHome classifications, transcripts and genomic coordinates, and structural data (including comparative models made for the PrionHome from manually curated alignments). We provide database usage examples for both vertebrate and fungal prion contexts. Using the database data, we have performed a detailed analysis of the compositional biases in known budding-yeast prionogenic sequences, showing that the only abundant bias pattern is for asparagine bias with subsidiary serine bias. We anticipate that this database will be a useful experimental aid and reference resource. It is freely available at: http://libaio.biol.mcgill.ca/prion.

Harbi, Djamel; Parthiban, Marimuthu; Gendoo, Deena M. A.; Ehsani, Sepehr; Kumar, Manish; Schmitt-Ulms, Gerold; Sowdhamini, Ramanathan; Harrison, Paul M.

2012-01-01

2

Human Prion Diseases with Variant Prion Protein  

Microsoft Academic Search

Recent molecular genetic studies revealed that the human prion protein (PrP) gene has a large repertoire of polymorphisms and mutations. Each variant PrP seems to correspond to a distinct type of prion diseases. We report herein that it is useful to classify prion diseases into plaque type or non-plaque type, based on the distribution of PrP in the central nervous

Tetsuyuki Kitamoto; Jun Tateishi

1994-01-01

3

Amyloid Core Formed of Full-Length Recombinant Mouse Prion Protein Involves Sequence 127-143 but Not Sequence 107-126  

PubMed Central

The principal event underlying the development of prion disease is the conversion of soluble cellular prion protein (PrPC) into its disease-causing isoform, PrPSc. This conversion is associated with a marked change in secondary structure from predominantly ?-helical to a high ?-sheet content, ultimately leading to the formation of aggregates consisting of ordered fibrillar assemblies referred to as amyloid. In vitro, recombinant prion proteins and short prion peptides from various species have been shown to form amyloid under various conditions and it has been proposed that, theoretically, any protein and peptide could form amyloid under appropriate conditions. To identify the peptide segment involved in the amyloid core formed from recombinant full-length mouse prion protein mPrP(23–230), we carried out seed-induced amyloid formation from recombinant prion protein in the presence of seeds generated from the short prion peptides mPrP(107–143), mPrP(107–126), and mPrP(127–143). Our results showed that the amyloid fibrils formed from mPrP(107–143) and mPrP(127–143), but not those formed from mPrP(107–126), were able to seed the amyloidogenesis of mPrP(23–230), showing that the segment residing in sequence 127–143 was used to form the amyloid core in the fibrillization of mPrP(23–230).

Chatterjee, Biswanath; Lee, Chung-Yu; Lin, Chen; Chen, Eric H.-L.; Huang, Chao-Li; Yang, Chien-Chih; Chen, Rita P.-Y.

2013-01-01

4

Prion Protein NMR Structure and Species Barrier for Prion Diseases  

Microsoft Academic Search

The structural basis of species specificity of transmissible spongiform encephalopathies, such as bovine spongiform encephalopathy or ``mad cow disease'' and Creutzfeldt-Jakob disease in humans, has been investigated using the refined NMR structure of the C-terminal domain of the mouse prion protein with residues 121-231. A database search for mammalian prion proteins yielded 23 different sequences for the fragment 124-226, which

Martin Billeter; Roland Riek; Gerhard Wider; Simone Hornemann; Rudi Glockshuber; Kurt Wuthrich

1997-01-01

5

Sequence variations of the bovine prion protein gene (PRNP) in native Korean Hanwoo cattle  

PubMed Central

Bovine spongiform encephalopathy (BSE) is one of the fatal neurodegenerative diseases known as transmissible spongiform encephalopathies (TSEs) caused by infectious prion proteins. Genetic variations correlated with susceptibility or resistance to TSE in humans and sheep have not been reported for bovine strains including those from Holstein, Jersey, and Japanese Black cattle. Here, we investigated bovine prion protein gene (PRNP) variations in Hanwoo cattle [Bos (B.) taurus coreanae], a native breed in Korea. We identified mutations and polymorphisms in the coding region of PRNP, determined their frequency, and evaluated their significance. We identified four synonymous polymorphisms and two non-synonymous mutations in PRNP, but found no novel polymorphisms. The sequence and number of octapeptide repeats were completely conserved, and the haplotype frequency of the coding region was similar to that of other B. taurus strains. When we examined the 23-bp and 12-bp insertion/deletion (indel) polymorphisms in the non-coding region of PRNP, Hanwoo cattle had a lower deletion allele and 23-bp del/12-bp del haplotype frequency than healthy and BSE-affected animals of other strains. Thus, Hanwoo are seemingly less susceptible to BSE than other strains due to the 23-bp and 12-bp indel polymorphisms.

Choi, Sangho

2012-01-01

6

Discriminant analysis of prion sequences for prediction of susceptibility  

PubMed Central

Prion diseases, including ovine scrapie, bovine spongiform encephalopathy (BSE), human kuru and Creutzfeldt–Jakob disease (CJD), originate from a conformational change of the normal cellular prion protein (PrPC) into abnormal protease-resistant prion protein (PrPSc). There is concern regarding these prion diseases because of the possibility of their zoonotic infections across species. Mutations and polymorphisms of prion sequences may influence prion-disease susceptibility through the modified expression and conformation of proteins. Rapid determination of susceptibility based on prion-sequence polymorphism information without complex structural and molecular biological analyses may be possible. Information regarding the effects of mutations and polymorphisms on prion-disease susceptibility was collected based on previous studies to classify the susceptibilities of sequences, whereas the BLOSUM62 scoring matrix and the position-specific scoring matrix were utilised to determine the distance of target sequences. The k-nearest neighbour analysis was validated with cross-validation methods. The results indicated that the number of polymorphisms did not influence prion-disease susceptibility, and three and four k-objects showed the best accuracy in identifying the susceptible group. Although sequences with negative polymorphisms showed relatively high accuracy for determination, polymorphisms may still not be an appropriate factor for estimating variation in susceptibility. Discriminant analysis of prion sequences with scoring matrices was attempted as a possible means of determining susceptibility to prion diseases. Further research is required to improve the utility of this method.

Lee, Ji-Hae; Bae, Se-Eun; Jung, Sunghoon; Ahn, Insung; Son, Hyeon Seok

2013-01-01

7

Discriminant analysis of prion sequences for prediction of susceptibility.  

PubMed

Prion diseases, including ovine scrapie, bovine spongiform encephalopathy (BSE), human kuru and Creutzfeldt-Jakob disease (CJD), originate from a conformational change of the normal cellular prion protein (PrP(C)) into abnormal protease-resistant prion protein (PrP(Sc)). There is concern regarding these prion diseases because of the possibility of their zoonotic infections across species. Mutations and polymorphisms of prion sequences may influence prion-disease susceptibility through the modified expression and conformation of proteins. Rapid determination of susceptibility based on prion-sequence polymorphism information without complex structural and molecular biological analyses may be possible. Information regarding the effects of mutations and polymorphisms on prion-disease susceptibility was collected based on previous studies to classify the susceptibilities of sequences, whereas the BLOSUM62 scoring matrix and the position-specific scoring matrix were utilised to determine the distance of target sequences. The k-nearest neighbour analysis was validated with cross-validation methods. The results indicated that the number of polymorphisms did not influence prion-disease susceptibility, and three and four k-objects showed the best accuracy in identifying the susceptible group. Although sequences with negative polymorphisms showed relatively high accuracy for determination, polymorphisms may still not be an appropriate factor for estimating variation in susceptibility. Discriminant analysis of prion sequences with scoring matrices was attempted as a possible means of determining susceptibility to prion diseases. Further research is required to improve the utility of this method. PMID:24113272

Lee, Ji-Hae; Bae, Se-Eun; Jung, Sunghoon; Ahn, Insung; Son, Hyeon Seok

2013-10-11

8

Prion protein NMR structure and species barrier for prion diseases  

PubMed Central

The structural basis of species specificity of transmissible spongiform encephalopathies, such as bovine spongiform encephalopathy or “mad cow disease” and Creutzfeldt–Jakob disease in humans, has been investigated using the refined NMR structure of the C-terminal domain of the mouse prion protein with residues 121–231. A database search for mammalian prion proteins yielded 23 different sequences for the fragment 124–226, which display a high degree of sequence identity and show relevant amino acid substitutions in only 18 of the 103 positions. Except for a unique isolated negative surface charge in the bovine protein, the amino acid differences are clustered in three distinct regions of the three-dimensional structure of the cellular form of the prion protein. Two of these regions represent potential species-dependent surface recognition sites for protein–protein interactions, which have independently been implicated from in vitro and in vivo studies of prion protein transformation. The third region consists of a cluster of interior hydrophobic side chains that may affect prion protein transformation at later stages, after initial conformational changes in the cellular protein.

Billeter, Martin; Riek, Roland; Wider, Gerhard; Hornemann, Simone; Glockshuber, Rudi; Wuthrich, Kurt

1997-01-01

9

The N-Terminal Sequence of Prion Protein Consists an Epitope Specific to the Abnormal Isoform of Prion Protein (PrPSc)  

PubMed Central

The conformation of abnormal prion protein (PrPSc) differs from that of cellular prion protein (PrPC), but the precise characteristics of PrPSc remain to be elucidated. To clarify the properties of native PrPSc, we attempted to generate novel PrPSc-specific monoclonal antibodies (mAbs) by immunizing PrP-deficient mice with intact PrPSc purified from bovine spongiform encephalopathy (BSE)-affected mice. The generated mAbs 6A12 and 8D5 selectivity precipitated PrPSc from the brains of prion-affected mice, sheep, and cattle, but did not precipitate PrPC from the brains of healthy animals. In histopathological analysis, mAbs 6A12 and 8D5 strongly reacted with prion-affected mouse brains but not with unaffected mouse brains without antigen retrieval. Epitope analysis revealed that mAbs 8D5 and 6A12 recognized the PrP subregions between amino acids 31–39 and 41–47, respectively. This indicates that a PrPSc-specific epitope exists in the N-terminal region of PrPSc, and mAbs 6A12 and 8D5 are powerful tools with which to detect native and intact PrPSc. We found that the ratio of proteinase K (PK)-sensitive PrPSc to PK-resistant PrPSc was constant throughout the disease time course.

Masujin, Kentaro; Kaku-Ushiki, Yuko; Miwa, Ritsuko; Okada, Hiroyuki; Shimizu, Yoshihisa; Kasai, Kazuo; Matsuura, Yuichi; Yokoyama, Takashi

2013-01-01

10

Recombinant Human Prion Protein Inhibits Prion Propagation in vitro.  

PubMed

Prion diseases are associated with the conformational conversion of the cellular prion protein (PrP(C)) into the pathological scrapie isoform (PrP(Sc)) in the brain. Both the in vivo and in vitro conversion of PrP(C) into PrP(Sc) is significantly inhibited by differences in amino acid sequence between the two molecules. Using protein misfolding cyclic amplification (PMCA), we now report that the recombinant full-length human PrP (rHuPrP23-231) (that is unglycosylated and lacks the glycophosphatidylinositol anchor) is a strong inhibitor of human prion propagation. Furthermore, rHuPrP23-231 also inhibits mouse prion propagation in a scrapie-infected mouse cell line. Notably, it binds to PrP(Sc), but not PrP(C), suggesting that the inhibitory effect of recombinant PrP results from blocking the interaction of brain PrP(C) with PrP(Sc). Our findings suggest a new avenue for treating prion diseases, in which a patient's own unglycosylated and anchorless PrP is used to inhibit PrP(Sc) propagation without inducing immune response side effects. PMID:24105336

Yuan, Jue; Zhan, Yi-An; Abskharon, Romany; Xiao, Xiangzhu; Martinez, Manuel Camacho; Zhou, Xiaochen; Kneale, Geoff; Mikol, Jacqueline; Lehmann, Sylvain; Surewicz, Witold K; Castilla, Joaquín; Steyaert, Jan; Zhang, Shulin; Kong, Qingzhong; Petersen, Robert B; Wohlkonig, Alexandre; Zou, Wen-Quan

2013-10-09

11

Recombinant Human Prion Protein Inhibits Prion Propagation in vitro  

PubMed Central

Prion diseases are associated with the conformational conversion of the cellular prion protein (PrPC) into the pathological scrapie isoform (PrPSc) in the brain. Both the in vivo and in vitro conversion of PrPC into PrPSc is significantly inhibited by differences in amino acid sequence between the two molecules. Using protein misfolding cyclic amplification (PMCA), we now report that the recombinant full-length human PrP (rHuPrP23-231) (that is unglycosylated and lacks the glycophosphatidylinositol anchor) is a strong inhibitor of human prion propagation. Furthermore, rHuPrP23-231 also inhibits mouse prion propagation in a scrapie-infected mouse cell line. Notably, it binds to PrPSc, but not PrPC, suggesting that the inhibitory effect of recombinant PrP results from blocking the interaction of brain PrPC with PrPSc. Our findings suggest a new avenue for treating prion diseases, in which a patient's own unglycosylated and anchorless PrP is used to inhibit PrPSc propagation without inducing immune response side effects.

Yuan, Jue; Zhan, Yi-An; Abskharon, Romany; Xiao, Xiangzhu; Martinez, Manuel Camacho; Zhou, Xiaochen; Kneale, Geoff; Mikol, Jacqueline; Lehmann, Sylvain; Surewicz, Witold K.; Castilla, Joaquin; Steyaert, Jan; Zhang, Shulin; Kong, Qingzhong; Petersen, Robert B.; Wohlkonig, Alexandre; Zou, Wen-Quan

2013-01-01

12

Prions  

PubMed Central

Prions are unprecedented infectious pathogens that cause a group of invariably fatal neurodegenerative diseases by an entirely novel mechanism. Prion diseases may present as genetic, infectious, or sporadic disorders, all of which involve modification of the prion protein (PrP). Bovine spongiform encephalopathy (BSE), scrapie of sheep, and Creutzfeldt–Jakob disease (CJD) of humans are among the most notable prion diseases. Prions are transmissible particles that are devoid of nucleic acid and seem to be composed exclusively of a modified protein (PrPSc). The normal, cellular PrP (PrPC) is converted into PrPSc through a posttranslational process during which it acquires a high ?-sheet content. The species of a particular prion is encoded by the sequence of the chromosomal PrP gene of the mammals in which it last replicated. In contrast to pathogens carrying a nucleic acid genome, prions appear to encipher strain-specific properties in the tertiary structure of PrPSc. Transgenetic studies argue that PrPSc acts as a template upon which PrPC is refolded into a nascent PrPSc molecule through a process facilitated by another protein. Miniprions generated in transgenic mice expressing PrP, in which nearly half of the residues were deleted, exhibit unique biological properties and should facilitate structural studies of PrPSc. While knowledge about prions has profound implications for studies of the structural plasticity of proteins, investigations of prion diseases suggest that new strategies for the prevention and treatment of these disorders may also find application in the more common degenerative diseases.

Prusiner, Stanley B.

1998-01-01

13

Protein misfolding and prion diseases  

Microsoft Academic Search

The prion diseases provide an intriguing connection between protein folding and neurodegenerative disease. In this review, I explore that importance of protein folding and misfolding in the prion diseases. Thermodynamic and kinetic models are examined in an effort to understand infectious, inherited and sporadic forms of these diseases. These concepts can be generalized to gain insight into other disorders of

Fred E Cohen

1999-01-01

14

Putative aggregation initiation sites in prion protein.  

PubMed

Misfolded prion protein, PrPSc, is believed to be the pathogenic agens in transmissible spongiform encephalopathies. Little is known about the autocatalytic misfolding process. Looking at the intrinsic properties of short sequence stretches, such as conformational flexibility and the tendency to populate extended conformers, we have examined the aggregation behaviour of various peptides within the region 106-157 of the sequence of human prion protein. We observed fast aggregation for the peptide containing residues I138-I-H-F141. This sequence, which is presented at the surface of cellular prion protein, PrPC, in an almost beta-sheet-like conformation, is therefore an ideal anchor-point for initial intermolecular contacts leading to oligomerization. We further report that the aggregation propensity of the neurotoxic peptide 106-126 appears to be centred in its termini and not in the central, alanine-rich sequence (A113-G-AAAA-G-A120). PMID:16545382

Ziegler, Jan; Viehrig, Christine; Geimer, Stefan; Rösch, Paul; Schwarzinger, Stephan

2006-03-10

15

Recent progress in prion and prion-like protein aggregation.  

PubMed

Prion diseases and prion-like protein misfolding diseases involve the accumulation of abnormally aggregated forms of the normal host proteins, such as prion protein and Tau protein. These proteins are special because of their self-duplicating and transmissible characteristics. Such abnormally aggregated proteins mainly formed in neurons, cause the neurons dysfunction, and finally lead to invariably fatal neurodegenerative diseases. Prion diseases appear not only in animals, such as bovine spongiform encephalopathy in cattle and scrapie in sheep, but also in humans, such as Creutzfeldt-Jacob disease, and even the same prion or prion-like proteins can have many different phenotypes. A lot of biological evidence has suggested that the molecular basis for different strains of prions could be hidden in protein conformations, and the misfolded proteins with conformations different from the normal proteins have been proved to be the main cause for protein aggregation. Crowded physiological environments can be imitated in vitro to study how the misfolding of these proteins leads to the diseases in vivo. In this review, we provide an overview of the existing structural information for prion and prion-like proteins, and discuss the post-translational modifications of prion proteins and the difference between prion and other infectious pathogens. We also discuss what makes a misfolded protein become an infectious agent, and show some examples of prion-like protein aggregation, such as Tau protein aggregation and superoxide dismutase 1 aggregation, as well as some cases of prion-like protein aggregation in crowded physiological environments. PMID:23709368

Yi, Chuan-Wei; Xu, Wen-Chang; Chen, Jie; Liang, Yi

2013-06-01

16

Prion Variants and Species Barriers Among Saccharomyces Ure2 Proteins  

Microsoft Academic Search

As hamster scrapie cannot infect mice, due to sequence differences in their PrP proteins, we find ''species barriers'' to transmission of the (URE3) prion in Saccharomyces cerevisiae among Ure2 proteins of S. cerevisiae, paradoxus, bayanus, cariocanus, and mikatae on the basis of differences among their Ure2p prion domain sequences. The rapid variation of the N-terminal Ure2p prion domains results in

Herman K. Edskes; Lindsay M. McCann; Andrea M. Hebert; Reed B. Wickner

2009-01-01

17

Prion Protein in Milk  

Microsoft Academic Search

BackgroundPrions are known to cause transmissible spongiform encephalopathies (TSE) after accumulation in the central nervous system. There is increasing evidence that prions are also present in body fluids and that prion infection by blood transmission is possible. The low concentration of the proteinaceous agent in body fluids and its long incubation time complicate epidemiologic analysis and estimation of spreading and

Nicola Franscini; Ahmed El Gedaily; Ulrich Matthey; Susanne Franitza; Man-Sun Sy; Alexander Bürkle; Martin Groschup; Ueli Braun; Ralph Zahn; Matthew Baylis

2006-01-01

18

Putative aggregation initiation sites in prion protein  

Microsoft Academic Search

Misfolded prion protein, PrPSc, is believed to be the pathogenic agens in transmissible spongiform encephalopathies. Little is known about the autocatalytic misfolding process. Looking at the intrinsic properties of short sequence stretches, such as conformational flexibility and the tendency to populate extended conformers, we have examined the aggregation behaviour of various peptides within the region 106–157 of the sequence of

Jan Ziegler; Christine Viehrig; Stefan Geimer; Paul Rösch; Stephan Schwarzinger

2006-01-01

19

Prion protein NMR structures of chickens, turtles, and frogs  

Microsoft Academic Search

The NMR structures of the recombinant prion proteins from chicken (Gallus gallus; chPrP), the red-eared slider turtle (Trachemys scripta; tPrP), and the African clawed frog (Xenopus laevis; xlPrP) are presented. The amino acid sequences of these prion proteins show 30% identity with mammalian prion proteins. All three species form the same molecular architecture as mammalian PrPC, with a long, flexibly

Luigi Calzolai; Dominikus A. Lysek; Daniel R. Pérez; Peter Güntert; Kurt Wüthrich

2005-01-01

20

Prion variants and species barriers among Saccharomyces Ure2 proteins.  

PubMed

As hamster scrapie cannot infect mice, due to sequence differences in their PrP proteins, we find "species barriers" to transmission of the [URE3] prion in Saccharomyces cerevisiae among Ure2 proteins of S. cerevisiae, paradoxus, bayanus, cariocanus, and mikatae on the basis of differences among their Ure2p prion domain sequences. The rapid variation of the N-terminal Ure2p prion domains results in protection against the detrimental effects of infection by a prion, just as the PrP residue 129 Met/Val polymorphism may have arisen to protect humans from the effects of cannibalism. Just as spread of bovine spongiform encephalopathy prion variant is less impaired by species barriers than is sheep scrapie, we find that some [URE3] prion variants are infectious to another yeast species while other variants (with the identical amino acid sequence) are not. The species barrier is thus prion variant dependent as in mammals. [URE3] prion variant characteristics are maintained even on passage through the Ure2p of another species. Ure2p of Saccharomyces castelli has an N-terminal Q/N-rich "prion domain" but does not form prions (in S. cerevisiae) and is not infected with [URE3] from Ure2p of other Saccharomyces. This implies that conservation of its prion domain is not for the purpose of forming prions. Indeed the Ure2p prion domain has been shown to be important, though not essential, for the nitrogen catabolism regulatory role of the protein. PMID:19124570

Edskes, Herman K; McCann, Lindsay M; Hebert, Andrea M; Wickner, Reed B

2009-01-05

21

Unaltered susceptibility to BSE in transgenic mice expressing human prion protein  

Microsoft Academic Search

PRION diseases are transmissible neurodegenerative conditions of humans and animals. Prions consist principally of a post-translationally modified form of prion protein (PrP), PrPSc, which is partly protease resistant1. Transmission of prion diseases between species is limited by a 'species barrier'2 determined in part by the degree of sequence homology between host PrP and inoculated prpSc (ref. 3) and by prion

John Collinge; Mark S. Palmer; Katie C. L. Sidle; Andrew F. Hill; Ian Gowland; Julie Meads; Emmanuel Asante; Ray Bradley; Lawrence J. Doey; Peter L. Lantos

1995-01-01

22

Prion protein in Caenorhabditis elegans  

PubMed Central

The infectious agent of prion diseases is believed to be nucleic acid-free particles composed of misfolded conformational isomers of a host protein known as prion protein (PrP). Although this “protein-only” concept is generally accepted, decades of extensive research have not been able to elucidate the mechanisms by which PrP misfolding leads to neurodegeneration and infectivity. The challenges in studying prion diseases relate in part to the limitations of mammalian prion models, which include the long incubation period post-infection until symptoms develop, the high expense of maintaining mammals for extended periods, as well as safety issues. In order to develop prion models incorporating a genetically tractable simple system with a well-defined neuronal system, we generated transgenic C. elegans expressing the mouse PrP behind the pan-neuronal ric-19 promoter (Pric-19). We show here that high expression of Pric-19::PrP in C. elegans can result in altered morphology, defective mobility and shortened lifespan. Low expression of Pric-19::PrP, however, does not cause any detectable harm. Using the dopamine neuron specific promoter Pdat-1, we also show that expression of the murine BAX, a pro-apoptotic member of the Bcl-2 family, causes dopamine neuron destruction in the nematode. However, co-expression of PrP inhibits BAX-mediated dopamine neuron degeneration, demonstrating for the first time that PrP has anti-BAX activity in living animals. Thus, these distinct PrP-transgenic C. elegans lines recapitulate a number of functional and neuropathological features of mammalian prion models and provide an opportunity for facile identification of genetic and environmental contributors to prion-associated pathology.

Park, Kyung-Won

2011-01-01

23

Prions: The Chemistry of Infectious Proteins  

Technology Transfer Automated Retrieval System (TEKTRAN)

A prion is pathological protein that causes a set of rare fatal neurological diseases called transmissible spongiform encephalopathies (TSE). TSE diseases occur in humans, sheep, goats, deer, elk, mink, cows and other mammals. A prion and the normal cellular prion protein (PrPC) have the same primar...

24

The Prion Protein Knockout Mouse  

PubMed Central

The key pathogenic event in prion disease involves misfolding and aggregation of the cellular prion protein (PrP). Beyond this fundamental observation, the mechanism by which PrP misfolding in neurons leads to injury and death remains enigmatic. Prion toxicity may come about by perverting the normal function of PrP. If so, understanding the normal function of PrP may help to elucidate the molecular mechansim of prion disease. Ablation of the Prnp gene, which encodes PrP, was instrumental for determining that the continuous production of PrP is essential for replicating prion infectivity. Since the structure of PrP has not provided any hints to its possible function, and there is no obvious phenotype in PrP KO mice, studies of PrP function have often relied on intuition and serendipity. Here, we enumerate the multitude of phenotypes described in PrP deficient mice, many of which manifest themselves only upon physiological challenge. We discuss the pleiotropic phenotypes of PrP deficient mice in relation to the possible normal function of PrP. The critical question remains open: which of these phenotypes are primary effects of PrP deletion and what do they tell us about the function of PrP?

Lindquist, Susan; Aguzzi, Adriano

2007-01-01

25

Healthy goats naturally devoid of prion protein  

PubMed Central

Prion diseases such as scrapie in small ruminants, bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in man, are fatal neurodegenerative disorders. These diseases result from the accumulation of misfolded conformers of the host-encoded prion protein (PrP) in the central nervous system. To date naturally-occurring PrP free animals have not been reported. Here we describe healthy non-transgenic animals, Norwegian Dairy Goats, lacking prion protein due to a nonsense mutation early in the gene. These animals are predicted to be resistant to prion disease and will be valuable for research and for production of prion-free products.

2012-01-01

26

Prion protein self-interaction in prion disease therapy approaches  

Microsoft Academic Search

Transmissible spongiform encephalopathies (TSEs) or prion diseases are unique disorders that are not caused by infectious micro-organisms (bacteria or fungi), viruses or parasites, but rather seem to be the result of an infectious protein. TSEs are comprised of fatal neurodegenerative disorders affecting both human and animals. Prion diseases cause sponge-like degeneration of neuronal tissue and include (among others) Creutzfeldt–Jacob disease

Alan Rigter; Jan Priem; Jan P. M. Langeveld; Alex Bossers

2011-01-01

27

Conversion of Bacterially Expressed Recombinant Prion Protein  

PubMed Central

The infectivity associated with prion disease sets it apart from a large group of late-onset neurodegenerative disorders that shares the characteristics of protein aggregation and neurodegeneration. The unconventional infectious agent, PrPSc, is an aberrantly folded form of the normal prion protein (PrPC) and the PrPC-to-PrPSc conversion is a critical pathogenic step in prion disease. Using the Protein Misfolding Cyclic Amplification technique, we converted folded bacterially expressed recombinant PrP into a Proteinase K-resistant and aggregated conformation (rPrP-res) in the presence of anionic lipid and RNA molecules. Moreover, high prion infectivity was demonstrated by intracerebral inoculation of rPrP-res into wild-type mice, which caused prion disease with a short incubation period. The establishment of the in vitro recombinant PrP conversion assay makes it feasible for us to explore the molecular basis behind the intriguing properties associated with prion infectivity.

Wang, Fei; Wang, Xinhe; Ma, Jiyan

2011-01-01

28

?-Cleavage of cellular prion protein  

PubMed Central

The cellular prion protein (PrPC) is subjected to various processing under physiological and pathological conditions, of which the ?-cleavage within the central hydrophobic domain not only disrupts a region critical for both PrP toxicity and PrPC to PrPSc conversion but also produces the N1 fragment that is neuroprotective and the C1 fragment that enhances the pro-apoptotic effect of staurosporine in one report and inhibits prion in another. The proteases responsible for the ?-cleavage of PrPC are controversial. The effect of ADAM10, ADAM17, and ADAM9 on N1 secretion clearly indicates their involvement in the ?-cleavage of PrPC, but there has been no report of direct PrPC ?-cleavage activity with any of the three ADAMs in a purified protein form. We demonstrated that, in muscle cells, ADAM8 is the primary protease for the ?-cleavage of PrPC, but another unidentified protease(s) must also play a minor role. We also found that PrPC regulates ADAM8 expression, suggesting that a close examination on the relationships between PrPC and its processing enzymes may reveal novel roles and underlying mechanisms for PrPC in non-prion diseases such as asthma and cancer.

Liang, Jingjing; Kong, Qingzhong

2012-01-01

29

Copper Binding in the Prion Protein  

PubMed Central

A conformational change of the prion protein is responsible for a class of neurodegenerative diseases called the transmissible spongiform encephalopathies that include mad cow disease and the human afflictions kuru and Creutzfeldt–Jakob disease. Despite the attention given to these diseases, the normal function of the prion protein in healthy tissue is unknown. Research over the past few years, however, demonstrates that the prion protein is a copper binding protein with high selectivity for Cu2+. The structural features of the Cu2+ binding sites have now been characterized and are providing important clues about the normal function of the prion protein and perhaps how metals or loss of protein function play a role in disease. The link between prion protein and copper may provide insight into the general, and recently appreciated, role of metals in neurodegenerative disease.

MILLHAUSER, GLENN L.

2010-01-01

30

Significance of prion and prion-like proteins in cancer development, progression and multi-drug resistance.  

PubMed

Prions are renowned for their role in neurodegenerative diseases in humans and animals. These are manifested as transmissible spongiform encephalopathies (TSEs) that result from the conversion of the normal glycosylphosphatidylinositol (GPI) anchored cellular prion protein (PrP(c)) to a misfolded, aggregated and pathogenic form, prion protein scrapie (PrP(Sc)) via a post-translational process followed by the accumulation of PrP(Sc) within the central nervous system. New research in this area has demonstrated that PrP is over-expressed in a variety of cancers including gastric, pancreatic and breast cancers, affecting the growth and invasiveness of these cancers as well as playing an important role in the acquisition of multi-drug resistant (MDR) gastric cancer. Prion-like doppel protein (Dpl), sharing 25% amino acid sequence homology to PrP and whose function remains elusive, has also been shown to exhibit a high level of expression in a number of cancers including acute myeloid leukemia's, myelodysplastic syndromes, gastric adenocarcinoma, anaplastic meningioma and astrocytomas. Furthermore, the tumour suppressor protein, p53, already known for its involvement in cancer development, has recently been shown to display prion-like tendencies. This review provides an overview of prions and prion-like proteins in mammals discussing their structure, function and role in cell function and disease. Furthermore, current research progress on the role of prion/prion-like proteins in the development, progression, and drug resistance of various cancers will be summarized. Potential implications for future development of new therapeutic treatments targeting prion and prion-like proteins will be discussed. PMID:24015988

Hinton, Caroline; Antony, Helma; Hashimi, Saeed M; Munn, Alan; Wei, Ming Q

2013-10-01

31

Application of quantitative real-time PCR in the detection of prion-protein gene species-specific DNA sequences in animal meals and feedstuffs.  

PubMed

This study describes a method for quantitative and species-specific detection of animal DNA from different species (cattle, sheep, goat, swine, and chicken) in animal feed and feed ingredients, including fish meals. A quantitative real-time PCR approach was carried out to characterize species-specific sequences based on the amplification of prion-protein sequence. Prion-protein species-specific primers and TaqMan probes were designed, and amplification protocols were optimized in order to discriminate the different species with short PCR amplicons. The real-time quantitative PCR approach was also compared to conventional species-specific PCR assays. The real-time quantitative assay allowed the detection of 10 pg of ruminant, swine, and poultry DNA extracted from meat samples processed at 130 degrees C for 40 min, 200 kPa. The origin of analyzed animal meals was characterized by the quantitative estimation of ruminant, swine, and poultry DNA. The TaqMan assay was used to quantify ruminant DNA in feedstuffs with 0.1% of meat and bone meal. In conclusion, the proposed molecular approach allowed the detection of species-specific DNA in animal meals and feedstuffs. PMID:16629035

Bellagamba, Federica; Comincini, Sergio; Ferretti, Luca; Valfrè, Franco; Moretti, Vittorio M

2006-04-01

32

Production of cattle lacking prion protein  

PubMed Central

Prion diseases are caused by propagation of misfolded forms of the normal cellular prion protein PrPC, such as PrPBSE in bovine spongiform encephalopathy (BSE) in cattle and PrPCJD in Creutzfeldt-Jakob disease (CJD) in humans1. Disruption of PrPC expression in mice, a species that does not naturally contract prion diseases, results in no apparent developmental abnormalities2–5. However, the impact of ablating PrPC function in natural host species of prion diseases is unknown. Here we report the generation and characterization of PrPC-deficient cattle produced by a sequential gene-targeting system6. At over 20 months of age, the cattle are clinically, physiologically, histopathologically, immunologically and reproductively normal. Brain tissue homogenates are resistant to prion propagation in vitro as assessed by protein misfolding cyclic amplification7. PrPC-deficient cattle may be a useful model for prion research and could provide industrial bovine products free of prion proteins.

Richt, Jurgen A; Kasinathan, Poothappillai; Hamir, Amir N; Castilla, Joaquin; Sathiyaseelan, Thillai; Vargas, Francisco; Sathiyaseelan, Janaki; Wu, Hua; Matsushita, Hiroaki; Koster, Julie; Kato, Shinichiro; Ishida, Isao; Soto, Claudio; Robl, James M; Kuroiwa, Yoshimi

2010-01-01

33

Prion Protein Interactions with Nucleic Acid: Possible Models for Prion Disease and Prion Function  

Microsoft Academic Search

Several models for the transmission and progression of prion diseases have arisen, evolving with the acquisition of new experimental results. It is generally accepted that the PrPSc protein is at least part of the infectious particle and the major protein component of the scrapie-associated fibrils (SAFs) that characterize the disease. An additional, unknown cofactor is most likely involved in transmission

Abraham Grossman; Brian Zeiler; Victor Sapirstein

2003-01-01

34

Polymorphisms and variants in the prion protein sequence of European moose (Alces alces), reindeer (Rangifer tarandus), roe deer (Capreolus capreolus) and fallow deer (Dama dama) in Scandinavia  

PubMed Central

The prion protein (PrP) sequence of European moose, reindeer, roe deer and fallow deer in Scandinavia has high homology to the PrP sequence of North American cervids. Variants in the European moose PrP sequence were found at amino acid position 109 as K or Q. The 109Q variant is unique in the PrP sequence of vertebrates. During the 1980s a wasting syndrome in Swedish moose, Moose Wasting Syndrome (MWS), was described. SNP analysis demonstrated a difference in the observed genotype proportions of the heterozygous Q/K and homozygous Q/Q variants in the MWS animals compared with the healthy animals. In MWS moose the allele frequencies for 109K and 109Q were 0.73 and 0.27, respectively, and for healthy animals 0.69 and 0.31. Both alleles were seen as heterozygotes and homozygotes. In reindeer, PrP sequence variation was demonstrated at codon 176 as D or N and codon 225 as S or Y. The PrP sequences in roe deer and fallow deer were identical with published GenBank sequences.

Wik, Lotta; Mikko, Sofia; Klingeborn, Mikael; Steen, Margareta; Simonsson, Magnus; Linne, Tommy

2012-01-01

35

Mutations of the Prion Protein Gene  

Microsoft Academic Search

.   Prion diseases are inherited in 5–15 % of cases. They are classified according to changes in the prion protein gene (PRNP) or conventionally according to phenotype as Gerstmann-Sträussler-Scheinker disease (GSS), fatal familial insomnia (FFI),\\u000a or familial Creutzfeldt-Jakob disease (fCJD). Point mutations and insertions within PRNP form the genetic background. We report the results of a systematic analysis of over

Gábor G. Kovács; Gianriccardo Trabattoni; Johannes A. Hainfellner; James W. Ironside; Richard S. G. Knight; Herbert Budka

2002-01-01

36

Prion search and cellular prion protein expression in stranded dolphins.  

PubMed

The recent description of a prion disease (PD) case in a free-ranging bottlenose dolphin (Tursiops truncatus) prompted us to carry out an extensive search for the disease-associated isoform (PrPSc) of the cellular prion protein (PrPC) in the brain and in a range of lymphoid tissues from 23 striped dolphins (Stenella coeruleoalba), 5 bottlenose dolphins and 2 Risso s dolphins (Grampus griseus) found stranded between 2007 and 2012 along the Italian coastline. Three striped dolphins and one bottlenose dolphin showed microscopic lesions of encephalitis, with no evidence of spongiform brain lesions being detected in any of the 30 free-ranging cetaceans investigated herein. Nevertheless, we could still observe a prominent PrPC immunoreactivity in the brain as well as in lymphoid tissues from these dolphins. Although immunohistochemical and Western blot investigations yielded negative results for PrPSc deposition in all tissues from the dolphins under study, the reported occurrence of a spontaneous PD case in a wild dolphin is an intriguing issue and a matter of concern for both prion biology and intra/inter-species transmissibility, as well as for cetacean conservation medicine. PMID:23034277

Di Guardo, G; Cocumelli, C; Meoli, R; Barbaro, K; Terracciano, G; Di Francesco, C E; Mazzariol, S; Eleni, C

37

The Octarepeat Region of the Prion Protein Is Conformationally Altered in PrPSc  

Microsoft Academic Search

BackgroundPrion diseases are fatal neurodegenerative disorders characterized by misfolding and aggregation of the normal prion protein PrPC. Little is known about the details of the structural rearrangement of physiological PrPC into a still-elusive disease-associated conformation termed PrPSc. Increasing evidence suggests that the amino-terminal octapeptide sequences of PrP (huPrP, residues 59–89), though not essential, play a role in modulating prion replication

Alice Y. Yam; Carol Man Gao; Xuemei Wang; Ping Wu; David Peretz; Jiyan Ma

2010-01-01

38

Disparate evolution of prion protein domains and the distinct origin of Doppel- and prion-related loci revealed by fish-to-mammal comparisons  

Microsoft Academic Search

Prions result from the misfolding and selective accumulation of the host-encoded prion protein (PrP) in the brain. Despite intensive research on mammalian models, basic questions about the biological role of PrP and the evolutionary origin of prion disease remain unanswered. Following our previous identification of novel fish PrP homologues, here we generated new fish PrP sequences and performed genomic analysis

Eric Rivera-Milla; Birgit Oidtmann; Cynthia H. Panagiotidis; Michael Baier; Theodoros Sklaviadis; Rudolf Hoffmann; Yi Zhou; Gonzalo P. Solis; Claudia A. O. Stuermer; Edward Málaga-Trillo

2005-01-01

39

Cellular prion protein: from physiology to pathology.  

PubMed

The human cellular prion protein (PrP(C)) is a glycosylphosphatidylinositol (GPI) anchored membrane glycoprotein with two N-glycosylation sites at residues 181 and 197. This protein migrates in several bands by Western blot analysis (WB). Interestingly, PNGase F treatment of human brain homogenates prior to the WB, which is known to remove the N-glycosylations, unexpectedly gives rise to two dominant bands, which are now known as C-terminal (C1) and N-terminal (N1) fragments. This resembles the ?-amyloid precursor protein (APP) in Alzheimer disease (AD), which can be physiologically processed by ?-, ?-, and ?-secretases. The processing of APP has been extensively studied, while the identity of the cellular proteases involved in the proteolysis of PrP(C) and their possible role in prion biology has remained limited and controversial. Nevertheless, there is a strong correlation between the neurotoxicity caused by prion proteins and the blockade of their normal proteolysis. For example, expression of non-cleavable PrP(C) mutants in transgenic mice generates neurotoxicity, even in the absence of infectious prions, suggesting that PrP(C) proteolysis is physiologically and pathologically important. As many mouse models of prion diseases have recently been developed and the knowledge about the proteases responsible for the PrP(C) proteolysis is accumulating, we examine the historical experimental evidence and highlight recent studies that shed new light on this issue. PMID:23202518

Yusa, Sei-ichi; Oliveira-Martins, José B; Sugita-Konishi, Yoshiko; Kikuchi, Yutaka

2012-11-14

40

Cellular Prion Protein: From Physiology to Pathology  

PubMed Central

The human cellular prion protein (PrPC) is a glycosylphosphatidylinositol (GPI) anchored membrane glycoprotein with two N-glycosylation sites at residues 181 and 197. This protein migrates in several bands by Western blot analysis (WB). Interestingly, PNGase F treatment of human brain homogenates prior to the WB, which is known to remove the N-glycosylations, unexpectedly gives rise to two dominant bands, which are now known as C-terminal (C1) and N-terminal (N1) fragments. This resembles the ?-amyloid precursor protein (APP) in Alzheimer disease (AD), which can be physiologically processed by ?-, ?-, and ?-secretases. The processing of APP has been extensively studied, while the identity of the cellular proteases involved in the proteolysis of PrPC and their possible role in prion biology has remained limited and controversial. Nevertheless, there is a strong correlation between the neurotoxicity caused by prion proteins and the blockade of their normal proteolysis. For example, expression of non-cleavable PrPC mutants in transgenic mice generates neurotoxicity, even in the absence of infectious prions, suggesting that PrPC proteolysis is physiologically and pathologically important. As many mouse models of prion diseases have recently been developed and the knowledge about the proteases responsible for the PrPC proteolysis is accumulating, we examine the historical experimental evidence and highlight recent studies that shed new light on this issue.

Yusa, Sei-ichi; Oliveira-Martins, Jose B.; Sugita-Konishi, Yoshiko; Kikuchi, Yutaka

2012-01-01

41

Polymerization of murine recombinant prion protein in nucleic acid solution  

Microsoft Academic Search

Summary.  ?Recombinant prion protein has been used earlier to understand the structural properties of cellular prion protein PrPC and to understand conformational change of PrPC to its isoform, PrPSc which is believed to be responsible for the prion disease. Here we report that murine recombinant prion protein, MoPrPC polymerizes in the presence of nucleic acid. The aggregation process and the properties

P. K. Nandi; E. Leclerc

1999-01-01

42

Chronic wasting disease prions are not transmissible to transgenic mice overexpressing human prion protein.  

PubMed

Chronic wasting disease (CWD) is a prion disease that affects free-ranging and captive cervids, including mule deer, white-tailed deer, Rocky Mountain elk and moose. CWD-infected cervids have been reported in 14 USA states, two Canadian provinces and in South Korea. The possibility of a zoonotic transmission of CWD prions via diet is of particular concern in North America where hunting of cervids is a popular sport. To investigate the potential public health risks posed by CWD prions, we have investigated whether intracerebral inoculation of brain and spinal cord from CWD-infected mule deer transmits prion infection to transgenic mice overexpressing human prion protein with methionine or valine at polymorphic residue 129. These transgenic mice have been utilized in extensive transmission studies of human and animal prion disease and are susceptible to BSE and vCJD prions, allowing comparison with CWD. Here, we show that these mice proved entirely resistant to infection with mule deer CWD prions arguing that the transmission barrier associated with this prion strain/host combination is greater than that observed with classical BSE prions. However, it is possible that CWD may be caused by multiple prion strains. Further studies will be required to evaluate the transmission properties of distinct cervid prion strains as they are characterized. PMID:20610667

Sandberg, Malin K; Al-Doujaily, Huda; Sigurdson, Christina J; Glatzel, Markus; O'Malley, Catherine; Powell, Caroline; Asante, Emmanuel A; Linehan, Jacqueline M; Brandner, Sebastian; Wadsworth, Jonathan D F; Collinge, John

2010-07-07

43

Characterization of Antibody Specific for Disease Associated Prion Protein.  

National Technical Information Service (NTIS)

Prion diseases are characterized by the presence of the abnormal scrapie isoform of prion protein (Prp(exp Sc)) in affected brains. A conformational change is believed to convert the normal cellular prion protein (PrP (expC)) into PrP(exp Sc). Detection o...

S. G. Chen

2004-01-01

44

Prion protein facilitates uptake of zinc into neuronal cells  

PubMed Central

Zinc is released into the synaptic cleft upon exocytotic stimuli, although the mechanism for its reuptake into neurons is unresolved. Here we show that the cellular prion protein enhances the uptake of zinc into neuronal cells. This prion-protein-mediated zinc influx requires the octapeptide repeats and amino-terminal polybasic region in the prion protein, but not its endocytosis. Selective antagonists of ?-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors block the prion protein-mediated zinc uptake, and the prion protein co-immunoprecipitates with both GluA1 and GluA2 AMPA receptor subunits. Zinc-sensitive intracellular tyrosine phosphatase activity is decreased in cells expressing prion protein and increased in the brains of prion-protein-null mice, providing evidence of a physiological consequence of this process. Prion protein-mediated zinc uptake is ablated in cells expressing familial associated mutants of the protein and in prion-infected cells. These data suggest that alterations in the cellular prion protein-mediated zinc uptake may contribute to neurodegeneration in prion and other neurodegenerative diseases.

Watt, Nicole T.; Taylor, David R.; Kerrigan, Talitha L.; Griffiths, Heledd H.; Rushworth, Jo V.; Whitehouse, Isobel J.; Hooper, Nigel M.

2012-01-01

45

Prions and the potential transmissibility of protein misfolding diseases.  

PubMed

Prions, or infectious proteins, represent a major frontier in the study of infectious agents. The prions responsible for mammalian transmissible spongiform encephalopathies (TSEs) are due primarily to infectious self-propagation of misfolded prion proteins. TSE prion structures remain ill-defined, other than being highly structured, self-propagating, and often fibrillar protein multimers with the capacity to seed, or template, the conversion of their normal monomeric precursors into a pathogenic form. Purified TSE prions usually take the form of amyloid fibrils, which are self-seeding ultrastructures common to many serious protein misfolding diseases such as Alzheimer's, Parkinson's, Huntington's and Lou Gehrig's (amytrophic lateral sclerosis). Indeed, recent reports have now provided evidence of prion-like propagation of several misfolded proteins from cell to cell, if not from tissue to tissue or individual to individual. These findings raise concerns that various protein misfolding diseases might have spreading, prion-like etiologies that contribute to pathogenesis or prevalence. PMID:23808331

Kraus, Allison; Groveman, Bradley R; Caughey, Byron

2013-06-28

46

Recombinant human prion protein fragment 90-231, a useful model to study prion neurotoxicity.  

PubMed

Transmissible spongiform encephalopathies (TSE), or prion diseases, are a group of fatal neurodegenerative disorders of animals and humans. Human diseases include Creutzfeldt-Jakob (CJD) and Gerstmann-Straussler-Scheinker (GSSD) diseases, fatal familial insomnia, and Kuru. Human and animal TSEs share a common histopathology with a pathognomonic triad: spongiform vacuolation of the grey matter, neuronal death, glial proliferation, and, more inconstantly, amyloid deposition. According to the "protein only" hypothesis, TSEs are caused by a unique post-translational conversion of normal, host-encoded, protease-sensitive prion protein (PrP(sen) or PrP(C)) to an abnormal disease-associated isoform (PrP(res) or PrP(Sc)). To investigate the molecular mechanism of neurotoxicity induced by PrP(Sc) we developed a protocol to obtain millimolar amounts of soluble recombinant polypeptide encompassing the amino acid sequence 90-231 of human PrP (hPrP90-231). This protein corresponds to the protease-resistant prion protein fragment that originates after amino-terminal truncation. Importantly, hPrP90-231 has a flexible backbone that, similar to PrP(C), can undergo to structural rearrangement. This peptide, structurally resembling PrP(C), can be converted in a PrP(Sc)-like conformation, and thus represents a valuable model to study prion neurotoxicity. In this article we summarized our experimental evidence on the molecular and structural mechanisms responsible of hPrP90-231 neurotoxicity on neuroectodermal cell line SHSY5Y and the effects of some PrP pathogen mutations identified in familial TSE. PMID:22321015

Corsaro, Alessandro; Thellung, Stefano; Villa, Valentina; Nizzari, Mario; Aceto, Antonio; Florio, Tullio

47

Neuronal zinc regulation and the prion protein  

PubMed Central

Zinc, the most abundant trace metal in the brain, has numerous functions in health and disease. It is released into the synaptic cleft alongside glutamate and this connection between zinc and glutamatergic neurotransmission allows the ion to modulate overall excitability of the brain and influence synaptic plasticity. To maintain healthy synapses, extracellular zinc levels need to be tightly regulated. We recently reported that the cellular prion protein (PrPC) can directly influence neuronal zinc concentrations by promoting zinc uptake via AMPA receptors. The octapeptide repeat region of PrPC is involved in zinc sensing or scavenging and the AMPA receptor provides the channel for transport of the metal across the membrane, facilitated by a direct interaction between the N-terminal polybasic region of PrPC and AMPA receptors. PrPC has been evolutionarily linked to the Zrt/Irt-like protein (ZIP) metal ion transport family with the C-terminus of PrPC sharing sequence similarities with the N-terminal extracellular domains of ZIP 5, 6 and 10. By incorporating the properties of ZIP transporters (both zinc sensing and zinc transport) into two existing neuronal proteins, (PrPC as zinc sensor, AMPA receptor as zinc transporter), neuronal cells are enhancing their biological efficiency and functionality.

Watt, Nicole T.; Griffiths, Heledd H.; Hooper, Nigel M.

2013-01-01

48

Role of Prion Protein Aggregation in Neurotoxicity  

PubMed Central

In several neurodegenerative diseases, such as Parkinson, Alzheimer’s, Huntington, and prion diseases, the deposition of aggregated misfolded proteins is believed to be responsible for the neurotoxicity that characterizes these diseases. Prion protein (PrP), the protein responsible of prion diseases, has been deeply studied for the peculiar feature of its misfolded oligomers that are able to propagate within affected brains, inducing the conversion of the natively folded PrP into the pathological conformation. In this review, we summarize the available experimental evidence concerning the relationship between aggregation status of misfolded PrP and neuronal death in the course of prion diseases. In particular, we describe the main findings resulting from the use of different synthetic (mainly PrP106-126) and recombinant PrP-derived peptides, as far as mechanisms of aggregation and amyloid formation, and how these different spatial conformations can affect neuronal death. In particular, most data support the involvement of non-fibrillar oligomers rather than actual amyloid fibers as the determinant of neuronal death.

Corsaro, Alessandro; Thellung, Stefano; Villa, Valentina; Nizzari, Mario; Florio, Tullio

2012-01-01

49

Prions and protein-folding diseases.  

PubMed

Prions represent a group of proteins with a unique capacity to fold into different conformations. One isoform is rich in beta-pleated sheets and can aggregate into amyloid that may be pathogenic. This abnormal form propagates itself by imposing its confirmation on the homologous normal host cell protein. Pathogenic prions have been shown to cause lethal neurodegenerative diseases in humans and animals. These diseases are sometimes infectious and hence referred to as transmissible spongiform encephalopathies. In the present review, the remarkable evolution of the heterodox prion concept is summarized. The origin of this phenomenon is based on information transfer between homologous proteins, without the involvement of nucleic acid-encoded mechanisms. Historically, kuru and Creutzfeldt-Jakob disease (CJD) were the first infectious prion diseases to be identified in man. It was their relationship to scrapie in sheep and experimental rodents that allowed an unravelling of the particular molecular mechanism that underlie the disease process. Transmission between humans has been documented to have occurred in particular contexts, including ritual cannibalism, iatrogenic transmission because of pituitary gland-derived growth hormone or the use in neurosurgical procedures of dura mater from cadavers, and the temporary use of a prion-contaminated protein-rich feed for cows. The latter caused a major outbreak of bovine spongiform encephalopathy, which spread to man by human consumption of contaminated meat, causing approximately 200 cases of variant CJD. All these epidemics now appear to be over because of measures taken to curtail further spread of prions. Recent studies have shown that the mechanism of protein aggregation may apply to a wider range of diseases in and possibly also outside the brain, some of which are relatively common such as Alzheimer's and Parkinson's diseases. Furthermore, it has become apparent that the phenomenon of prion aggregation may have a wider physiological importance, but a full understanding of this remains to be defined. It may involve maintaining neuronal functions and possibly contributing to the establishment of long-term memory. PMID:21481020

Norrby, E

2011-05-12

50

Copper Binding to the N-Terminal Tandem Repeat Regions of Mammalian and Avian Prion Protein  

Microsoft Academic Search

Mammalian prion protein (PrP) is a normal cellular protein (PrPc) which through post-translational modification produces the infectious prion protein (PrPsc). We have shown, using mass spectrometry, that synthetic peptides containing three or four copies of an octapeptide repeat sequence (PHGGGWGQ), found in a highly conserved N-terminal domain of PrP, preferentially bind copper over other metals. Peptides from the analogous region

M. P. Hornshaw; J. R. Mcdermott; J. M. Candy

1995-01-01

51

Polymorphism of prion protein gene in Arctic fox (Vulpes lagopus).  

PubMed

Prion diseases are fatal neurodegenerative disorders of humans and certain other mammals. Prion protein gene (Prnp) is associated with susceptibility and species barrier to prion diseases. No natural and experimental prion diseases have been documented to date in Arctic fox. In the present study, coding region of Prnp from 135 Arctic foxes were cloned and screened for polymorphisms. Our results indicated that the Arctic fox Prnp open reading frame (ORF) contains 771 nucleotides encoding 257 amino acids. Four single nucleotide polymorphisms (SNPs) (G312C, A337G, C541T, and A723G) were identified. SNPs G312C and A723G produced silent mutations, but SNPs A337G and C541T resulted in a M-V change at codon 113 and R-C at codon 181, respectively. The Arctic fox Prnp amino acid sequence was similar to that of the dog (XM 542906). In short, this study provides preliminary information about genotypes of Prnp in Arctic fox. PMID:18622757

Wan, Jiayu; Bai, Xue; Liu, Wensen; Xu, Jing; Xu, Ming; Gao, Hongwei

2008-07-13

52

Codon 178 mutation of the human prion protein gene in a German family (Backer family): sequencing data from 72-year-old celloidin-embedded brain tissue  

Microsoft Academic Search

Familial Creutzfeldt-Jakob disease was first described in a family from northern Germany in the 1920s (Backer family). PCR amplification of DNA extracted from brain tissue embedded in celloidin 72 years ago shows a GAC to AAC substitution at codon 178 of the prion protein gene. This mutation is associated with fatal familial insomnia and familial Creutzfeldt-Jakob disease in a number

H. A. Kretzschmar; M. Neumann; D. Stavrou

1995-01-01

53

Role of a Novel Topological Form of the Prion Protein in Prion Disease.  

National Technical Information Service (NTIS)

Prion diseases are commonly associated with the presence of a conformationally altered form of the prion protein (PrPSc). However, there is mounting evidence that PrPSc is not directly toxic to neurons; it may require interaction with other gene products ...

R. S. Stewart

2008-01-01

54

Role of a Novel Topological Form of the Prion Protein in Prion Disease.  

National Technical Information Service (NTIS)

Most(but not all) cases of prion disease are associated with a conformationally altered form of the prion protein (PrP) known as PrPSc. Several lines of evidence indicate that while PrpSc is the infectious molecule, it may not be the proximate cause of to...

R. S. Stewart

2005-01-01

55

Role of a Novel Topological Form of the Prion Protein in Prion Disease.  

National Technical Information Service (NTIS)

Most(but not all) cases of prion disease are associated with a conformationally altered form of the prion protein (PrP) known as PrPSc. Several lines of evidence indicate that while PrpSc is the infectious molecule, it may not be the proximate cause of to...

R. S. Stewart

2006-01-01

56

Transmissible Proteins: Expanding the Prion Heresy  

PubMed Central

The once-heretical concept that a misfolded protein is the infectious agent responsible for prion diseases is now widely accepted. Recent exciting research has led not only to the end of the skepticism that proteins can transmit disease but also to expanding the concept that transmissible proteins might be at the root of some of the most prevalent human illnesses. At the same time, the idea that biological information can be transmitted by propagation of protein (mis)folding raises the possibility that heritable protein agents may be operating as epigenetic factors in normal biological functions and participating in evolutionary adaptation.

Soto, Claudio

2012-01-01

57

Antibody to DNA detects scrapie but not normal prion protein  

Microsoft Academic Search

Prion diseases, a group of fatal neurodegenerative disorders, are characterized by the presence of the abnormal scrapie isoform of prion protein (PrPSc) in affected brains. A conformational change is believed to convert the normal cellular prion protein into PrPSc. Detection of PrPSc for diagnosis and prophylaxis is impaired because available Abs recognizing epitopes on PrP fail to distinguish between PrPSc

Wen-Quan Zou; Jian Zheng; Donald M. Gray; Pierluigi Gambetti; Shu G. Chen

2004-01-01

58

First report of polymorphisms in the prion-like protein gene ( PRND): implications for human prion diseases  

Microsoft Academic Search

The aim of this study was to investigate the possible involvement of genetic variation in the prion-like protein gene (PRND), which encodes the doppel protein (Dpl), in the aetiology of human prion diseases. Patients with sporadic, infectious or genetic forms of human prion diseases and controls were systematically screened, using the single-strand conformational polymorphism method, for genetic variants of the

Katell Peoc'h; Caroline Guérin; Jean-Philippe Brandel; Jean-Marie Launay; Jean-Louis Laplanche

2000-01-01

59

Prion Protein Amino Acid Determinants of Differential Susceptibility and Molecular Feature of Prion Strains in Mice and Voles  

PubMed Central

The bank vole is a rodent susceptible to different prion strains from humans and various animal species. We analyzed the transmission features of different prions in a panel of seven rodent species which showed various degrees of phylogenetic affinity and specific prion protein (PrP) sequence divergences in order to investigate the basis of vole susceptibility in comparison to other rodent models. At first, we found a differential susceptibility of bank and field voles compared to C57Bl/6 and wood mice. Voles showed high susceptibility to sheep scrapie but were resistant to bovine spongiform encephalopathy, whereas C57Bl/6 and wood mice displayed opposite features. Infection with mouse-adapted scrapie 139A was faster in voles than in C57Bl/6 and wood mice. Moreover, a glycoprofile change was observed in voles, which was reverted upon back passage to mice. All strains replicated much faster in voles than in mice after adapting to the new species. PrP sequence comparison indicated a correlation between the transmission patterns and amino acids at positions 154 and 169 (Y and S in mice, N and N in voles). This correlation was confirmed when inoculating three additional rodent species: gerbils, spiny mice and oldfield mice with sheep scrapie and 139A. These rodents were chosen because oldfield mice do have the 154N and 169N substitutions, whereas gerbil and spiny mice do not have them. Our results suggest that PrP residues 154 and 169 drive the susceptibility, molecular phenotype and replication rate of prion strains in rodents. This might have implications for the assessment of host range and molecular traceability of prion strains, as well as for the development of improved animal models for prion diseases.

Agrimi, Umberto; Nonno, Romolo; Dell'Omo, Giacomo; Di Bari, Michele Angelo; Conte, Michela; Chiappini, Barbara; Esposito, Elena; Di Guardo, Giovanni; Windl, Otto; Vaccari, Gabriele; Lipp, Hans-Peter

2008-01-01

60

On the kinetics of infection by pathogenic prion protein molecules  

NASA Astrophysics Data System (ADS)

Literature data on the transmission of spongiform encephalopathies between mammal species point to the importance of methionine residuies in species barriers. This in turn favours the assumption of an oligomerization of identical metastable pathogenic prion protein molecules as the rate-determining step in those diseases. Published experimental data on the analogous case of yeast prion proteins closely agree with the proposed scheme.

Durup, Jean

1997-03-01

61

Elucidation of Prion Protein Conformational Changes Associated with Infectivity by Fluorescence Spectroscopy.  

National Technical Information Service (NTIS)

Prion diseases are fatal neurodegenerative diseases of mammals. They are characterized by the conversion of normal prion protein (PrP) to a misfolded conformational state that accumulates as plaques in the brain. The diagnosis of prion diseases relies on ...

M. McGuirl

2006-01-01

62

Elucidation of Prion Protein Conformational Changes Associated With Infectivity by Fluorescence Spectroscopy.  

National Technical Information Service (NTIS)

Prion diseases are fatal neurodegenerative diseases of mammals. They are characterized by the conversion of normal prion protein (PrP) to a misfolded conformational state that accumulates as plaques in the brain. The diagnosis of prion diseases relies on ...

M. A. McGuirl

2004-01-01

63

Elucidation of Prion Protein Conformational Changes Associated With Infectivity by Fluorescence Spectroscopy.  

National Technical Information Service (NTIS)

Prion diseases are fatal neurodegenerative diseases of mammals. They are characterized by the conversion of normal prion protein (PrP) to a misfolded conformational state that accumulates as plaques in the brain. The diagnosis of prion diseases relies on ...

M. A. McGuirl

2005-01-01

64

Attachment of pathogenic prion protein to model oxide surfaces.  

PubMed

Prions are the infectious agents in the class of fatal neurodegenerative diseases known as transmissible spongiform encephalopathies, which affect humans, deer, sheep, and cattle. Prion diseases of deer and sheep can be transmitted via environmental routes, and soil is has been implicated in the transmission of these diseases. Interaction with soil particles is expected to govern the transport, bioavailability and persistence of prions in soil environments. A mechanistic understanding of prion interaction with soil components is critical for understanding the behavior of these proteins in the environment. Here, we report results of a study to investigate the interactions of prions with model oxide surfaces (Al2O3, SiO2) using quartz crystal microbalance with dissipation monitoring and optical waveguide light mode spectroscopy. The efficiency of prion attachment to Al2O3 and SiO2 depended strongly on pH and ionic strength in a manner consistent with electrostatic forces dominating interaction with these oxides. The presence of the N-terminal portion of the protein appeared to promote attachment to Al2O3 under globally electrostatically repulsive conditions. We evaluated the utility of recombinant prion protein as a surrogate for prions in attachment experiments and found that its behavior differed markedly from that of the infectious agent. Our findings suggest that prions would tend to associate with positively charged mineral surfaces in soils (e.g., iron and aluminum oxides). PMID:23611152

Jacobson, Kurt H; Kuech, Thomas R; Pedersen, Joel A

2013-05-30

65

Prion protein induced signaling cascades in monocytes  

SciTech Connect

Prion proteins play a central role in transmission and pathogenesis of transmissible spongiform encephalopathies. The cellular prion protein (PrP{sup C}), whose physiological function remains elusive, is anchored to the surface of a variety of cell types including neurons and cells of the lymphoreticular system. In this study, we investigated the response of a mouse monocyte/macrophage cell line to exposure with PrP{sup C} fusion proteins synthesized with a human Fc-tag. PrP{sup C} fusion proteins showed an attachment to the surface of monocyte/macrophages in nanomolar concentrations. This was accompanied by an increase of cellular tyrosine phosphorylation as a result of activated signaling pathways. Detailed investigations exhibited activation of downstream pathways through a stimulation with PrP fusion proteins, which include phosphorylation of ERK{sub 1,2} and Akt kinase. Macrophages opsonize and present antigenic structures, contact lymphocytes, and deliver cytokines. The findings reported here may become the basis of understanding the molecular function of PrP{sup C} in monocytes and macrophages.

Krebs, Bjarne [Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Muenchen (Germany); Dorner-Ciossek, Cornelia [CNS Research III, Boehringer Ingelheim Pharma GmbH and Co KG, Biberach/Riss (Germany); Schmalzbauer, Ruediger [Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich (Germany); Vassallo, Neville [Department of Physiology and Biochemistry, University of Malta, Msida (Malta); Herms, Jochen [Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich (Germany); Kretzschmar, Hans A. [Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich (Germany)]. E-mail: Hans.Kretzschmar@med.uni-muenchen.de

2006-02-03

66

Lysosomotropic Agents and Cysteine Protease Inhibitors Inhibit Scrapie-Associated Prion Protein Accumulation  

PubMed Central

We report that lysosomotropic agents and cysteine protease inhibitors inhibited protease-resistant prion protein accumulation in scrapie-infected neuroblastoma cells. The inhibition occurred without either apparent effects on normal prion protein biosynthesis or turnover or direct interactions with prion protein molecules. The findings introduce two new classes of inhibitors of the formation of protease-resistant prion protein.

Doh-ura, Katsumi; Iwaki, Toru; Caughey, Byron

2000-01-01

67

Prevalent mutations of human prion protein: a molecular modeling and molecular dynamics study.  

PubMed

Point mutations in the human prion protein gene, leading to amino acid substitutions in the human prion protein contribute to conversion of PrPC to PrPSc and amyloid formation, resulting in prion diseases such as familial Creutzfeldt-Jakob disease (CJD), Gerstmann-Straussler-Scheinker disease (GSS), and fatal familial insomnia. We have investigated impressions of prevalent mutations including Q217R, D202N, F198S, on the human prion protein and compared the mutant models with wild types. Structural analyses of models were performed with molecular modeling and molecular dynamics simulation methods. According to our results, frequently occurred mutations are observed in conserved and fully conserved sequences of human prion protein and the most fluctuation values occur in the Helix 1 around residues 144-152 and C-terminal end of the Helix 2. Our analysis of results obtained from MD simulation clearly shows that this long-range effect plays an important role in the conformational fluctuations in mutant structures of human prion protein. Results obtained from molecular modeling such as creation or elimination of some hydrogen bonds, increase or decrease of the accessible surface area and molecular surface, loss or accumulation of negative or positive charges on specific positions, and altering the polarity and pKa values, show that amino acid point mutations, though not urgently change the stability of PrP, might have some local impacts on the protein interactions which are required for oligomerization into fibrillar species. PMID:21875156

Behmard, Esmaeil; Abdolmaleki, Parviz; Asadabadi, Ebrahim Barzegari; Jahandideh, Samad

2011-10-01

68

In Silico Analysis of Prion Protein Mutants: A Comparative Study by Molecular Dynamics Approach.  

PubMed

Polymorphisms in the human prion proteins lead to amino acid substitutions by the conversion of PrPC to PrPSc and amyloid formation, resulting in prion diseases such as familial Creutzfeldt-Jakob disease, Gerstmann-Straussler-Scheinker disease and fatal familial insomnia. Cation-? interaction is a non-covalent binding force that plays a significant role in protein stability. Here, we employ a novel approach by combining various in silico tools along with molecular dynamics simulation to provide structural and functional insight into the effect of mutation on the stability and activity of mutant prion proteins. We have investigated impressions of prevalent mutations including 1E1S, 1E1P, 1E1U, 1E1P, 1FKC and 2K1D on the human prion proteins and compared them with wild type. Structural analyses of the models were performed with the aid of molecular dynamics simulation methods. According to our results, frequently occurred mutations were observed in conserved sequences of human prion proteins and the most fluctuation values appear in the 2K1D mutant model at around helix 4 with residues ranging from 190 to 194. Our observations in this study could help to further understand the structural stability of prion proteins. PMID:23723004

George Priya Doss, C; Rajith, B; Rajasekaran, R; Srajan, Jain; Nagasundaram, N; Debajyoti, C

2013-05-31

69

Epitope scanning indicates structural differences in brain-derived monomeric and aggregated mutant prion proteins related to genetic prion diseases.  

PubMed

Genetic Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker syndrome, fatal familial insomnia and prion protein cerebral amyloid angiopathy are clinically and neuropathologically distinct neurodegenerative diseases linked to mutations in the PRNP gene encoding the cellular prion protein (PrPC). How sequence variants of PRNP encode the information to specify these disease phenotypes is not known. It is suggested that each mutation produces a misfolded variant of PrPC with specific neurotoxic properties. However, structural studies of recombinant PrP did not detect major differences between wild-type and mutant molecules, pointing to the importance of investigating mutant PrPs from mammalian brains. We used surface plasmon resonance and a slot-blot immunoassay to analyse the antibody-binding profiles of soluble and insoluble PrP molecules extracted from the brains of transgenic mice modelling different prion diseases. By measuring the reactivity of monoclonal antibodies against different PrP epitopes, we obtained evidence of conformational differences between wild-type and mutant PrPs, and among different mutants. We detected structural heterogeneity in both monomeric and aggregated PrP, supporting the hypothesis that the phenotype of genetic prion diseases is encoded by mutant PrP conformation and assembly state. PMID:23808898

Tapella, Laura; Stravalaci, Matteo; Bastone, Antonio; Biasini, Emiliano; Gobbi, Marco; Chiesa, Roberto

2013-09-15

70

Doxycycline Control of Prion Protein Transgene Expression Modulates Prion Disease in Mice  

Microsoft Academic Search

Conversion of the cellular prion protein (PrPC) into the pathogenic isoform (PrPSc) is the fundamental event underlying transmission and pathogenesis of prion disease. To control the expression of PrPC in transgenic (Tg) mice, we used a tetracycline controlled transactivator (tTA) driven by the PrP gene control elements and a tTA-responsive promoter linked to a PrP gene [Gossen, M. and Bujard,

Patrick Tremblay; Zeev Meiner; Maria Galou; Cornelia Heinrich; Chris Petromilli; Thomas Lisse; Juliana Cayetano; Marilyn Torchia; William Mobley; Hermann Bujard; Stephen J. Dearmond

1998-01-01

71

Prion protein and its role in signal transduction.  

PubMed

Prion diseases are a class of fatal neurodegenerative disorders that can be sporadic, genetic or iatrogenic. They are characterized by the unique nature of their etiologic agent: prions (PrP(Sc)). A prion is an infectious protein with the ability to convert the host-encoded cellular prion protein (PrP(C)) into new prion molecules by acting as a template. Since Stanley B. Prusiner proposed the "protein-only" hypothesis for the first time, considerable effort has been put into defining the role played by PrP(C) in neurons. However, its physiological function remains unclear. This review summarizes the major findings that support the involvement of PrP(C) in signal transduction. PMID:23479001

Didonna, Alessandro

2013-03-11

72

De novo design of synthetic prion domains  

PubMed Central

Prions are important disease agents and epigenetic regulatory elements. Prion formation involves the structural conversion of proteins from a soluble form into an insoluble amyloid form. In many cases, this structural conversion is driven by a glutamine/asparagine (Q/N)-rich prion-forming domain. However, our understanding of the sequence requirements for prion formation and propagation by Q/N-rich domains has been insufficient for accurate prion propensity prediction or prion domain design. By focusing exclusively on amino acid composition, we have developed a prion aggregation prediction algorithm (PAPA), specifically designed to predict prion propensity of Q/N-rich proteins. Here, we show not only that this algorithm is far more effective than traditional amyloid prediction algorithms at predicting prion propensity of Q/N-rich proteins, but remarkably, also that PAPA is capable of rationally designing protein domains that function as prions in vivo.

Toombs, James A.; Petri, Michelina; Paul, Kacy R.; Kan, Grace Y.; Ben-Hur, Asa; Ross, Eric D.

2012-01-01

73

Prion protein and the transmissible spongiform encephalopathies.  

PubMed

Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases that occur in a wide variety of mammals. In humans, TSE diseases include kuru, sporadic and iatrogenic Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), and fatal familial insomnia (FFI). So far, TSE diseases occur only rarely in humans; however, scrapie is a widespread problem in sheep, and the recent epidemic of bovine spongiform encephalopathy (BSE or mad cow disease) has seriously affected the British cattle industry. Of special concern is the recent appearance of a new variant of CJD in humans that is suspected of being caused by infections from BSE-infected cattle products. In all these diseases, an abnormal form of a host protein, prion protein (PrP), is essential for the pathogenic process. The relationship of this protein to the transmissible agent is currently the subject of great interest and controversy and is the subject of this review. PMID:17708907

Caughey, B; Chesebro, B

1997-02-01

74

The structural stability of wild-type horse prion protein.  

PubMed

Prion diseases (e.g. Creutzfeldt-Jakob disease (CJD), variant CJD (vCJD), Gerstmann-Straussler-Scheinker syndrome (GSS), Fatal Familial Insomnia (FFI) and Kuru in humans, scrapie in sheep, bovine spongiform encephalopathy (BSE or 'mad-cow' disease) and chronic wasting disease (CWD) in cattles) are invariably fatal and highly infectious neurodegenerative diseases affecting humans and animals. However, by now there have not been some effective therapeutic approaches or medications to treat all these prion diseases. Rabbits, dogs, and horses are the only mammalian species reported to be resistant to infection from prion diseases isolated from other species. Recently, the ?2-?2 loop has been reported to contribute to their protein structural stabilities. The author has found that rabbit prion protein has a strong salt bridge ASP177-ARG163 (like a taut bow string) keeping this loop linked. This paper confirms that this salt bridge also contributes to the structural stability of horse prion protein. Thus, the region of ?2-?2 loop might be a potential drug target region. Besides this very important salt bridge, other four important salt bridges GLU196-ARG156-HIS187, ARG156-ASP202 and GLU211-HIS177 are also found to greatly contribute to the structural stability of horse prion protein. Rich databases of salt bridges, hydrogen bonds and hydrophobic contacts for horse prion protein can be found in this paper. PMID:21875155

Zhang, Jiapu

2011-10-01

75

Cytoplasmic Prion Protein Induces Forebrain Neurotoxicity  

PubMed Central

SUMMARY The prion protein (PrP) is essential for the pathogenesis of prion disease. PrP has been detected in the cytosol of neurons and transgenic mice expressing PrP in the cytosol (cyPrP) under a pan-neuronal promoter developed rapid cerebellar granule neuron degeneration. Yet, it remains unclear whether cyPrP is capable to cause toxicity in other neuronal populations. Here, we report that transgenic mice expressing cyPrP in the forebrain neurons developed behavioral abnormalities including clasping and hyperactivity. These mice had a reduced thickness in cortex and developed astrogliosis in hippocampal and cortical regions. Moreover, cyPrP in these mice was recognized by the A11 anti-oligomer antibody and was associated with the hydrophobic lipid core of membranes, indicating that cyPrP oligomer caused membrane perturbation contributes to cyPrP neurotoxicity. Together, our results clearly revealed that cyPrP is able to cause toxicity in different neuronal populations, supporting a role of cyPrP in PrP-mediated neurodegenerative disorders.

Wang, Xinhe; Bowers, Stephanie L.; Wang, Fei; Pu, Xin-an; Nelson, Randy J.; Ma, Jiyan

2009-01-01

76

SSCP analysis and sequencing of the human prion protein gene (PRNP) detects two different 24 bp deletions in an atypical Alzheimer`s disease family  

SciTech Connect

Alzheimer`s disease (AD) is a progressive, degenerative neurological disorder of the central nervous system. AD is the fourth leading cause of death in elderly persons 65 years or older in Western industrialized societies. The etiology of AD is unknown, but clinical, pathological, epidemiological, and molecular investigations suggest it is etiologically heterogeneous. Mutations in the amyloid protein are rare and segregate with the disease in a few early-onset familial AD (FAD) families. Similarities between AD and the unconventional viral (UCV) diseases, and between the amyloid and prion proteins, implicate the human prion protein gene (PRNP) as another candidate gene. Single strand conformation polymorphism (SSCP) analysis was used to screen for mutations at this locus in 82 AD patients from 54 families (30 FAD), vs. 39 age-matched controls. A 24-bp deletion around codon 68 that codes for one of five Gly-Pro rich octarepeats was identified in two affected sibs and one offspring of one late-onset FAD family. Two other affected sibs, three unaffected sibs, and three offspring from this family, in addition to one sporadic AD patient and three age-matched controls, were heterozygous for another octarepeat deletion located around codon 82. Two of the four affected sibs had features of PD, including one who was autopsy-verified AD and PD. Although these deletions were found infrequently in other AD patients and controls, they appear to be a rare polymorphism that is segregating in this FAD family. It does not appear that mutations at the PRNP locus are frequently associated with AD in this population. 54 refs., 4 figs.

Perry, R.T.; Go, R.C.P.; Harrell, L.E.; Acton, R.T. [Univ. of Alabama, Birmingham, AL (United States)

1995-02-27

77

Crucial Role for Prion Protein Membrane Anchoring in the Neuroinvasion and Neural Spread of Prion Infection ?  

PubMed Central

In nature prion diseases are usually transmitted by extracerebral prion infection, but clinical disease results only after invasion of the central nervous system (CNS). Prion protein (PrP), a host-encoded glycosylphosphatidylinositol (GPI)-anchored membrane glycoprotein, is necessary for prion infection and disease. Here, we investigated the role of the anchoring of PrP on prion neuroinvasion by studying various inoculation routes in mice expressing either anchored or anchorless PrP. In control mice with anchored PrP, intracerebral or sciatic nerve inoculation resulted in rapid CNS neuroinvasion and clinical disease (154 to 156 days), and after tongue, ocular, intravenous, or intraperitoneal inoculation, CNS neuroinvasion was only slightly slower (193 to 231 days). In contrast, in anchorless PrP mice, these routes resulted in slow and infrequent CNS neuroinvasion. Only intracerebral inoculation caused brain PrPres, a protease-resistant isoform of PrP, and disease in both types of mice. Thus, anchored PrP was an essential component for the rapid neural spread and CNS neuroinvasion of prion infection.

Klingeborn, Mikael; Race, Brent; Meade-White, Kimberly D.; Rosenke, Rebecca; Striebel, James F.; Chesebro, Bruce

2011-01-01

78

Depressive-like behaviour of mice lacking cellular prion protein  

Microsoft Academic Search

Cellular Prion Protein (PrPC) is known to mediate a protective role in several neurological conditions such as ischemia and epilepsy. However, so far, little information is available concerning the role of PrPC in psychiatric disorders such as depression. Here, we have used PrPC null mice to examine a putative role of PrPC in depressive-like states. Prion protein null mice exhibited

Vinicius M. Gadotti; Stephan P. Bonfield; Gerald W. Zamponi

79

Copper-dependent functions for the prion protein  

Microsoft Academic Search

Prion diseases such as bovine spongiform encephalopathy and Creutzfeldt-Jakob disease are fatal neurodegenerative diseases.\\u000a These diseases are characterized by the conversion of a normal cellular protein, the prion protein, to an abnormal isoform\\u000a that is thought to be responsible for both pathogenesis in the disease and the infectious nature of the disease agent. Understanding\\u000a the biology and metabolism of the

David R. Brown; Judyth Sassoon

2002-01-01

80

Structural studies of the scrapie prion protein by electron crystallography  

Microsoft Academic Search

Because the insolubility of the scrapie prion protein (PrPSc) has frustrated structural studies by x-ray crystallography or NMR spectroscopy, we used electron crystallography to characterize the structure of two infectious variants of the prion protein. Isomorphous two-dimensional crystals of the N-terminally truncated PrPSc (PrP 27-30) and a miniprion (PrPSc106) were identified by negative stain electron microscopy. Image processing allowed the

Holger Wille; Melissa D. Michelitsch; Vincent Guénebaut; Surachai Supattapone; Ana Serban; Fred E. Cohen; David A. Agard

2002-01-01

81

Prevalence of lymphoreticular prion protein accumulation in UK tissue samples  

Microsoft Academic Search

This study aims to provide an estimate of the number of individuals in the UK who may be incubating variant Creutzfeldt-Jakob disease and at risk of causing iatrogenic spread of the disease. Lymphoreticular accumulation of prion protein is a consistent feature of variant Creutzfeldt-Jakob at autopsy and has also been demonstrated in the pre-clinical phase. Immunohistochemical accumulation of prion protein

David A Hilton; Azra C Ghani; Lisa Conyers; Philip Edwards; Linda McCardle; Diane Ritchie; Mark Penney; Doha Hegazy; James W Ironside

2004-01-01

82

Antigen Retrieval in Prion Protein Immunohistochemistry  

Microsoft Academic Search

Transmissible spongiform encephalopathies are a group of neurodegenerative diseases occurring in both humans and animals and are most likely caused by prions. Neuropathological confirmation of the clinical diagnosis has been a problem because of the difficulty in epitope retrieval from formalin-fixed, paraffin-embedded brain specimens. Many different protocols for the detection of prions in brain tissue have been used. Thus far,

Bart Van Everbroeck; Philippe Pals; Jean-Jacques Martin; Patrick Cras

1999-01-01

83

Manganese Upregulates Cellular Prion Protein and Contributes to Altered Stabilization and Proteolysis: Relevance to Role of Metals in Pathogenesis of Prion Disease  

Technology Transfer Automated Retrieval System (TEKTRAN)

Prion diseases are fatal neurodegenerative diseases resulting from misfolding of normal cellular prion (PrP**C) into an abnormal form of scrapie prion (PrP**Sc). The cellular mechanisms underlying the misfolding of PrP**C are not well understood. Since cellular prion proteins harbor divalent metal b...

84

Targeting cellular prion protein reverses early cognitive deficits and neurophysiological dysfunction in prion-infected mice.  

PubMed

Currently, no treatment can prevent the cognitive and motor decline associated with widespread neurodegeneration in prion disease. However, we previously showed that targeting endogenous neuronal prion protein (PrP(C)) (the precursor of its disease-associated isoform, PrP(Sc)) in mice with early prion infection reversed spongiform change and prevented clinical symptoms and neuronal loss. We now show that cognitive and behavioral deficits and impaired neurophysiological function accompany early hippocampal spongiform pathology. Remarkably, these behavioral and synaptic impairments recover when neuronal PrP(C) is depleted, in parallel with reversal of spongiosis. Thus, early functional impairments precede neuronal loss in prion disease and can be rescued. Further, they occur before extensive PrP(Sc) deposits accumulate and recover rapidly after PrP(C) depletion, supporting the concept that they are caused by a transient neurotoxic species, distinct from aggregated PrP(Sc). These data suggest that early intervention in human prion disease may lead to recovery of cognitive and behavioral symptoms. PMID:17270731

Mallucci, Giovanna R; White, Melanie D; Farmer, Michael; Dickinson, Andrew; Khatun, Husna; Powell, Andrew D; Brandner, Sebastian; Jefferys, John G R; Collinge, John

2007-02-01

85

In Vitro and In Vivo Neurotoxicity of Prion Protein Oligomers  

Microsoft Academic Search

The mechanisms underlying prion-linked neurodegeneration remain to be elucidated, despite several recent advances in this field. Herein, we show that soluble, low molecular weight oligomers of the full-length prion protein (PrP), which possess characteristics of PrP to PrPsc conversion intermediates such as partial protease resistance, are neurotoxic in vitro on primary cultures of neurons and in vivo after subcortical stereotaxic

Steve Simoneau; Human Rezaei; Nicole Salès; Gunnar Kaiser-Schulz; Maxime Lefebvre-Roque; Catherine Vidal; Jean-Guy Fournier; Julien Comte; Franziska Wopfner; Jeanne Grosclaude; Hermann Schätzl; Corinne Ida Lasmézas

2007-01-01

86

A Molecular Analysis Of Prion Protein Expression In Alzheimer's Disease  

Microsoft Academic Search

In Prion Diseases, misfolding of neuronal prion protein (PrPC) to a pathogenic isomer (PrPSC) is associated with neuronal death. Previous pathological studies have demonstrated increased immunoreactivity of PrPC at A? plaques in Alzheimer's Disease, and it has been suggested that this either reflects a role for PrPC in the neuronal response to stress or is a feature of the neuropathogenesis

Alisdair McNeill

2004-01-01

87

Proposed Three-Dimensional Structure for the Cellular Prion Protein  

Microsoft Academic Search

Prion diseases are a group of neurodegenerative disorders in humans and animals that seem to result from a conformational change in the prion protein (PrP). Utilizing data obtained by circular dichroism and infrared spectroscopy, computational studies predicted the three-dimensional structure of the cellular form of PrP (PrP^C). A heuristic approach consisting of the prediction of secondary structures and of an

Ziwei Huang; Jean-Marc Gabriel; Michael A. Baldwin; Robert J. Fletterick; Fred E. Cohen

1994-01-01

88

Structure and polymorphism of the mouse prion protein gene.  

PubMed Central

Missense mutations in the prion protein (PrP) gene, overexpression of the cellular isoform of PrP (PrPC), and infection with prions containing the scrapie isoform of PrP (PrPSc) all cause neurodegenerative disease. To understand better the physiology and expression of PrPC, we retrieved mouse PrP gene (Prn-p) yeast artificial chromosome (YAC), cosmid, phage, and cDNA clones. Physical mapping positions Prn-p approximately 300 kb from ecotropic virus integration site number 4 (Evi-4), compatible with failure to detect recombination between Prn-p and Evi-4 in genetic crosses. The Prn-pa allele encompasses three exons, with exons 1 and 2 encoding the mRNA 5' untranslated region. Exon 2 has no equivalent in the Syrian hamster and human PrP genes. The Prn-pb gene shares this intron/exon structure but harbors an approximately 6-kb deletion within intron 2. While the Prn-pb open reading frame encodes two amino acid substitutions linked to prolonged scrapie incubation periods, a deletion of intron 2 sequences also characterizes inbred strains such as RIII/S and MOLF/Ei with shorter incubation periods, making a relationship between intron 2 size and scrapie pathogenesis unlikely. The promoter regions of a and b Prn-p alleles include consensus Sp1 and AP-1 sites, as well as other conserved motifs which may represent binding sites for as yet unidentified transcription factors. Images

Westaway, D; Cooper, C; Turner, S; Da Costa, M; Carlson, G A; Prusiner, S B

1994-01-01

89

Proteolytic processing of the prion protein in health and disease  

PubMed Central

A variety of physiological functions, not only restricted to the nervous system, are discussed for the cellular prion protein (PrPC). A prominent, non-physiological property of PrPC is the conversion into its pathogenic isoform (PrPSc) during fatal, transmissible, and neurodegenerative prion diseases. The prion protein is subject to posttranslational proteolytic processing and these cleavage events have been shown i) to regulate its physiological functions, ii) to produce biologically active fragments, and iii) to potentially influence the course of prion disease. Here, we give an overview on the proteolytic processing under physiological and pathological conditions and critically review what is currently known about the three main cleavage events of the prion protein, namely ?-cleavage, ?-cleavage, and ectodomain shedding. The biological relevance of resulting fragments as well as controversies regarding candidate proteases, with special emphasis on members of the A-disintegrin-and-metalloproteinase (ADAM) family, will be discussed. In addition, we make suggestions aimed at facilitating clarity and progress in this important research field. The better understanding of this issue will not only answer basic questions in prion biology but will likely impact research on other neurodegenerative diseases as well.

Altmeppen, Hermann C; Puig, Berta; Dohler, Frank; Thurm, Dana K; Falker, Clemens; Krasemann, Susanne; Glatzel, Markus

2012-01-01

90

Targeted knock-down of cellular prion protein expression in myelinating Schwann cells does not alter mouse prion pathogenesis.  

PubMed

In naturally acquired transmissible spongiform encephalopathies, the pathogenic agents or prions spread from the sites of initial peripheral uptake or replication to the brain where they cause progressive and fatal neurodegeneration. Routing via the peripheral nervous system is considered to be one of the main pathways to the central nervous system. Replication of prions in Schwann cells is viewed as a potentially important mechanism for efficient prion spread along nerves. Here we used a Cre-loxP mouse transgenetic approach to disrupt host-encoded prion protein (PrP(C)) specifically in myelinating Schwann cells. Despite the use of infection routes targeting highly myelinated nerves, there was no alteration in mouse prion pathogenesis, suggesting that conversion-dependent, centripetal spread of prions does not crucially rely on PrP(C) expressed by myelinating Schwann cells. PMID:23388201

Halliez, Sophie; Chesnais, Nathalie; Mallucci, Giovanna; Vilotte, Marthe; Langevin, Christelle; Jaumain, Emilie; Laude, Hubert; Vilotte, Jean-Luc; Béringue, Vincent

2013-02-06

91

Prion gene sequence variation within diverse groups of U.S. sheep, beef cattle, and deer.  

PubMed

Prions are proteins that play a central role in transmissible spongiform encephalopathies in a variety of mammals. Among the most notable prion disorders in ungulates are scrapie in sheep, bovine spongiform encephalopathy in cattle, and chronic wasting disease in deer. Single nucleotide polymorphisms in the sheep prion gene ( PRNP) have been correlated with susceptibility to natural scrapie in some populations. Similar correlations have not been reported in cattle or deer; however, characterization of PRNP nucleotide diversity in those species is incomplete. This report describes nucleotide sequence variation and frequency estimates for the PRNP locus within diverse groups of U.S. sheep, U.S. beef cattle, and free-ranging deer ( Odocoileus virginianus and O. hemionus from Wyoming). DNA segments corresponding to the complete prion coding sequence and a 596-bp portion of the PRNP promoter region were amplified and sequenced from DNA panels with 90 sheep, 96 cattle, and 94 deer. Each panel was designed to contain the most diverse germplasm available from their respective populations to facilitate polymorphism detection. Sequence comparisons identified a total of 86 polymorphisms. Previously unreported polymorphisms were identified in sheep (9), cattle (13), and deer (32). The number of individuals sampled within each population was sufficient to detect more than 95% of all alleles present at a frequency greater than 0.02. The estimation of PRNP allele and genotype frequencies within these diverse groups of sheep, cattle, and deer provides a framework for designing accurate genotype assays for use in genetic epidemiology, allele management, and disease control. PMID:14722726

Heaton, Michael P; Leymaster, Kreg A; Freking, Brad A; Hawk, Deedra A; Smith, Timothy P L; Keele, John W; Snelling, Warren M; Fox, James M; Chitko-McKown, Carol G; Laegreid, William W

2003-11-01

92

Low copper and high manganese levels in prion protein plaques  

USGS Publications Warehouse

Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

Johnson, Christopher J.; Gilbert, PUPA; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

2013-01-01

93

Low Copper and High Manganese Levels in Prion Protein Plaques  

PubMed Central

Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecht, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; Aiken, Judd M.; McKenzie, Debbie

2013-01-01

94

Expression and characterisation of fully posttranslationally modified cellular prion protein in Pichia pastoris.  

PubMed

Abstract Prion diseases are fatal neurodegenerative diseases which occur as sporadic, genetic, and transmissible disorders. A molecular hallmark of prion diseases is the conformational conversion of the host-encoded cellular form of the prion protein (PrPC) into its misfolded pathogenic isoform (PrPSc). PrPSc is the main component of the pathological and infectious prion agent. The study of the conversion mechanism from PrPC to PrPSc is a major field in prion research. PrPC is glycosylated and attached to the plasma membrane via its glycosyl phosphatidyl inositol (GPI)-anchor. In this study we established and characterised the expression of fully posttranslationally modified mammalian Syrian golden hamster PrPC in the yeast Pichia pastoris using native PrPC-specific N- and C-terminal signal sequences. In vivo as well as in vitro-studies demonstrated that the signal sequences controlled posttranslational processing and trafficking of native PrPC, resulting in PrPC localised in the plasma membrane of P. pastoris. In addition, the glycosylation pattern of native PrPC could be confirmed. PMID:23893688

Marbach, Jendrik; Zentis, Peter; Ellinger, Philipp; Müller, Henrik; Birkmann, Eva

2013-11-01

95

Small RNA deep sequencing reveals a distinct miRNA signature released in exosomes from prion-infected neuronal cells  

PubMed Central

Prion diseases are transmissible neurodegenerative disorders affecting both humans and animals. The cellular prion protein, PrPC, and the abnormal infectious form, PrPSc, are found associated with exosomes, which are small 50–130 nm vesicles released from cells. Exosomes also contain microRNAs (miRNAs), a class of non-coding RNA, and have been utilized to identify miRNA signatures for diagnosis of disease. While some miRNAs are deregulated in prion-infected brain tissue, the role of miRNA in circulating exosomes released during prion disease is unknown. Here, we investigated the miRNA profile in exosomes released from prion-infected neuronal cells. We performed the first small RNA deep sequencing study of exosomes and demonstrated that neuronal exosomes contain a diverse range of RNA species including retroviral RNA repeat regions, messenger RNA fragments, transfer RNA fragments, non-coding RNA, small nuclear RNA, small nucleolar RNA, small cytoplasmic RNA, silencing RNA as well as known and novel candidate miRNA. Significantly, we show that exosomes released by prion-infected neuronal cells have increased let-7b, let-7i, miR-128a, miR-21, miR-222, miR-29b, miR-342-3p and miR-424 levels with decreased miR-146 a levels compared to non-infected exosomes. Overall, these results demonstrate that circulating exosomes released during prion infection have a distinct miRNA signature that can be utilized for diagnosis and understanding pathogenic mechanisms in prion disease.

Bellingham, Shayne A.; Coleman, Bradley M.; Hill, Andrew F.

2012-01-01

96

Cytoplasmic Expression of Mouse Prion Protein Causes Severe Toxicity in C. elegans  

PubMed Central

To test if Caenorhabditis elegans could be established as a model organism for prion study, we created transgenic C. elegans expressing the cytosolic form of the mouse prion .protein, MoPrP(23-231), which lacks the N-terminal signal sequence and the C-terminal glycosylphosphatidylinisotol (GPI) anchor site. We report here that transgenic worms expressing MoPrP(23-231)–CFP exhibited a wide range of distinct phenotypes: from normal growth and development, reduced mobility and development delay, complete paralysis and development arrest, to embryonic lethality. Similar levels of MoPrP (23-231)-CFP were produced in animals exhibiting these distinct phenotypes, suggesting that MoPrP (23-231)-CFP might have misfolded into distinct toxic species. In combining with the observation that mutations in PrP that affect prion pathogenesis also affect the toxic phenotypes in C. elegans, we conclude that the prion protein folding mechanism is similar in mammals and C. elegans. Thus, C. elegans can be a useful model organism for prion research.

Park, Kyung-Won; Li, Liming

2008-01-01

97

Comparative syntheses of peptides and peptide thioesters derived from mouse and human prion proteins.  

PubMed

Prions are suspected as causative agents of several neuropathogenic diseases, even though the mode of their action is still not clear. A combination of chemical and recombinant syntheses can provide suitable probes for explanation of prions role in pathogenesis of neurodegenerative diseases. However, the prions contain several difficult sequences for synthesis by Fmoc/tBu approach. For that reason, the peptide thioesters as the key building blocks for chemical syntheses of proteins by native chemical ligation were employed. A scan of the mouse prion domain 93-231 was carried out in order to discover availability of derived thioesters as the suitable building blocks for a total chemical synthesis of the prion protein based probes. The synthesis on 2-chlorotritylchloride resin was utilized and after a deprotection of the samples for analysis, the peptide segments were purified and characterized. If the problems were detected during the synthesis, the segment was re-synthesized either using the special pseudoproline dipeptides or by splitting its molecule to two or three smaller segments, which were prepared easier. The protected segments, prepared correctly without any deletion and in sufficient amounts, were coupled either with EtSH after DIC/DMAP activation or with p-Ac-NH-Ph-SH using PyBOP activation to yield corresponding thioesters. In some special cases, the other techniques of thioester formation, like sulfonamide-safety catch and/or trimethylaluminium approach were utilized. PMID:22212592

Sebestík, Jaroslav; Zawada, Zbigniew; Safa?ík, Martin; Hlavá?ek, Jan

2012-01-03

98

Scrapie Prion Protein Structural Constraints Obtained by Limited Proteolysis and Mass Spectrometry  

Microsoft Academic Search

Elucidation of the structure of scrapie prion protein (PrPSc), essential to understand the molecular mechanism of prion transmission, continues to be one of the major challenges in prion research and is hampered by the insolubility and polymeric character of PrPSc. Limited proteolysis is a useful tool to obtain insight on structural features of proteins: proteolytic enzymes cleave proteins more readily

Gustavo Sajnani; Miguel A. Pastrana; Irina Dynin; Bruce Onisko; Jesús R. Requena

2008-01-01

99

Prions in Yeast  

PubMed Central

The concept of a prion as an infectious self-propagating protein isoform was initially proposed to explain certain mammalian diseases. It is now clear that yeast also has heritable elements transmitted via protein. Indeed, the “protein only” model of prion transmission was first proven using a yeast prion. Typically, known prions are ordered cross-? aggregates (amyloids). Recently, there has been an explosion in the number of recognized prions in yeast. Yeast continues to lead the way in understanding cellular control of prion propagation, prion structure, mechanisms of de novo prion formation, specificity of prion transmission, and the biological roles of prions. This review summarizes what has been learned from yeast prions.

Liebman, Susan W.; Chernoff, Yury O.

2012-01-01

100

Probing Structural Differences in Prion Protein Isoforms by Tyrosine Nitration†  

PubMed Central

Two conformational isomers of recombinant hamster prion protein (residues 90-232) have been probed by reaction with two tyrosine nitration reagents, peroxynitrite and tetranitromethane. Two conserved tyrosine residues (tyrosines 149 and 150) are not labeled by either reagent in the normal cellular form of the prion protein. These residues become reactive after the protein has been converted to the ?-oligomeric isoform, which is used as a model of the fibrillar form that causes disease. After conversion, a decrease in reactivity is noted for two other conserved residues, tyrosine 225 and tyrosine 226, whereas little to no effect was observed for other tyrosines. Thus, tyrosine nitration has identified two specific regions of the normal prion protein isoform that undergo a change in chemical environment upon conversion to a structure that is enriched in ?-sheet.

Lennon, Christopher W.; Cox, Holly D.; Hennelly, Scott P.; Chelmo, Sam J.; McGuirl, Michele A.

2008-01-01

101

Single treatment with RNAi against prion protein rescues early neuronal dysfunction and prolongs survival in mice with prion disease.  

PubMed

Prion diseases are fatal neurodegenerative conditions for which there is no effective treatment. Prion propagation involves the conversion of cellular prion protein, PrP(C), to its conformational isomer, PrP(Sc), which accumulates in disease. Here, we show effective therapeutic knockdown of PrP(C) expression using RNAi in mice with established prion disease. A single administration of lentivirus expressing a shRNA targeting PrP into each hippocampus of mice with established prion disease significantly prolonged survival time. Treated animals lived 19% and 24% longer than mice given an "empty" lentivirus, or not treated, respectively. Lentivirally mediated RNAi of PrP also prevented the onset of behavioral deficits associated with early prion disease, reduced spongiform degeneration, and protected against neuronal loss. In contrast, mice receiving empty virus or no treatment developed early cognitive impairment and showed severe spongiosis and neuronal loss. The focal use of RNAi therapeutically in prion disease further supports strategies depleting PrP(C), which we previously established to be a valid target for prion-based treatments. This approach can now be used to define the temporal, quantitative, and regional requirements for PrP knockdown for effective treatment of prion disease and to explore mechanisms involved in predegenerative neuronal dysfunction and its rescue. PMID:18632556

White, Melanie D; Farmer, Michael; Mirabile, Ilaria; Brandner, Sebastian; Collinge, John; Mallucci, Giovanna R

2008-07-16

102

Single treatment with RNAi against prion protein rescues early neuronal dysfunction and prolongs survival in mice with prion disease  

PubMed Central

Prion diseases are fatal neurodegenerative conditions for which there is no effective treatment. Prion propagation involves the conversion of cellular prion protein, PrPC, to its conformational isomer, PrPSc, which accumulates in disease. Here, we show effective therapeutic knockdown of PrPC expression using RNAi in mice with established prion disease. A single administration of lentivirus expressing a shRNA targeting PrP into each hippocampus of mice with established prion disease significantly prolonged survival time. Treated animals lived 19% and 24% longer than mice given an “empty” lentivirus, or not treated, respectively. Lentivirally mediated RNAi of PrP also prevented the onset of behavioral deficits associated with early prion disease, reduced spongiform degeneration, and protected against neuronal loss. In contrast, mice receiving empty virus or no treatment developed early cognitive impairment and showed severe spongiosis and neuronal loss. The focal use of RNAi therapeutically in prion disease further supports strategies depleting PrPC, which we previously established to be a valid target for prion-based treatments. This approach can now be used to define the temporal, quantitative, and regional requirements for PrP knockdown for effective treatment of prion disease and to explore mechanisms involved in predegenerative neuronal dysfunction and its rescue.

White, Melanie D.; Farmer, Michael; Mirabile, Ilaria; Brandner, Sebastian; Collinge, John; Mallucci, Giovanna R.

2008-01-01

103

Marked increase of neuronal prion protein immunoreactivity in Alzheimer's disease and human prion diseases  

Microsoft Academic Search

In neurodegenerative disorders including Alzheimer's disease (AD), free radical damage to lipids, carbohydrates, proteins and DNA has been demonstrated to play a key pathogenetic role. In vitro studies have suggested a function of the cellular prion protein (PrPc) in the defense against oxidative stress. Therefore, we investigated the distribution of PrPc immunoreactivity in hippocampus (sectors CA4-CA1), subiculum (Sub), entorhinal (EC),

T. Voigtländer; S. Klöppel; P. Birner; C. Jarius; H. Flicker; S. Verghese-Nikolakaki; T. Sklaviadis; M. Guentchev; H. Budka

2001-01-01

104

Inherited Prion Disease A117V Is Not Simply a Proteinopathy but Produces Prions Transmissible to Transgenic Mice Expressing Homologous Prion Protein.  

PubMed

Prions are infectious agents causing fatal neurodegenerative diseases of humans and animals. In humans, these have sporadic, acquired and inherited aetiologies. The inherited prion diseases are caused by one of over 30 coding mutations in the human prion protein (PrP) gene (PRNP) and many of these generate infectious prions as evidenced by their experimental transmissibility by inoculation to laboratory animals. However, some, and in particular an extensively studied type of Gerstmann-Sträussler-Scheinker syndrome (GSS) caused by a PRNP A117V mutation, are thought not to generate infectious prions and instead constitute prion proteinopathies with a quite distinct pathogenetic mechanism. Multiple attempts to transmit A117V GSS have been unsuccessful and typical protease-resistant PrP (PrP(Sc)), pathognomonic of prion disease, is not detected in brain. Pathogenesis is instead attributed to production of an aberrant topological form of PrP, C-terminal transmembrane PrP ((Ctm)PrP). Barriers to transmission of prion strains from one species to another appear to relate to structural compatibility of PrP in host and inoculum and we have therefore produced transgenic mice expressing human 117V PrP. We found that brain tissue from GSS A117V patients did transmit disease to these mice and both the neuropathological features of prion disease and presence of PrP(Sc) was demonstrated in the brains of recipient transgenic mice. This PrP(Sc) rapidly degraded during laboratory analysis, suggesting that the difficulty in its detection in patients with GSS A117V could relate to post-mortem proteolysis. We conclude that GSS A117V is indeed a prion disease although the relative contributions of (Ctm)PrP and prion propagation in neurodegeneration and their pathogenetic interaction remains to be established. PMID:24086135

Asante, Emmanuel A; Linehan, Jacqueline M; Smidak, Michelle; Tomlinson, Andrew; Grimshaw, Andrew; Jeelani, Asif; Jakubcova, Tatiana; Hamdan, Shyma; Powell, Caroline; Brandner, Sebastian; Wadsworth, Jonathan D F; Collinge, John

2013-09-26

105

Inherited Prion Disease A117V Is Not Simply a Proteinopathy but Produces Prions Transmissible to Transgenic Mice Expressing Homologous Prion Protein  

PubMed Central

Prions are infectious agents causing fatal neurodegenerative diseases of humans and animals. In humans, these have sporadic, acquired and inherited aetiologies. The inherited prion diseases are caused by one of over 30 coding mutations in the human prion protein (PrP) gene (PRNP) and many of these generate infectious prions as evidenced by their experimental transmissibility by inoculation to laboratory animals. However, some, and in particular an extensively studied type of Gerstmann-Sträussler-Scheinker syndrome (GSS) caused by a PRNP A117V mutation, are thought not to generate infectious prions and instead constitute prion proteinopathies with a quite distinct pathogenetic mechanism. Multiple attempts to transmit A117V GSS have been unsuccessful and typical protease-resistant PrP (PrPSc), pathognomonic of prion disease, is not detected in brain. Pathogenesis is instead attributed to production of an aberrant topological form of PrP, C-terminal transmembrane PrP (CtmPrP). Barriers to transmission of prion strains from one species to another appear to relate to structural compatibility of PrP in host and inoculum and we have therefore produced transgenic mice expressing human 117V PrP. We found that brain tissue from GSS A117V patients did transmit disease to these mice and both the neuropathological features of prion disease and presence of PrPSc was demonstrated in the brains of recipient transgenic mice. This PrPSc rapidly degraded during laboratory analysis, suggesting that the difficulty in its detection in patients with GSS A117V could relate to post-mortem proteolysis. We conclude that GSS A117V is indeed a prion disease although the relative contributions of CtmPrP and prion propagation in neurodegeneration and their pathogenetic interaction remains to be established.

Asante, Emmanuel A.; Linehan, Jacqueline M.; Smidak, Michelle; Tomlinson, Andrew; Grimshaw, Andrew; Jeelani, Asif; Jakubcova, Tatiana; Hamdan, Shyma; Powell, Caroline; Brandner, Sebastian; Wadsworth, Jonathan D. F.; Collinge, John

2013-01-01

106

Scrapie pathogenesis in brain and retina: Effects of prion protein expression in neurons and astrocytes  

Microsoft Academic Search

Brain damage in the transmissible spongiform encephalopathies or prion diseases is associated with the conversion of normal\\u000a host prion protein to an abnormal protease-resistant isoform, and expression of prion protein is required for susceptibility\\u000a to these diseases. This article reviews the data on studies using transgenic mice expressing prion protein in specific individual\\u000a cell types to study the roles of

Bruce Chesebro; Richard Race; Lisa Kercher

2005-01-01

107

Prion protein accumulation in lipid rafts of mouse aging brain.  

PubMed

The cellular form of the prion protein (PrP(C)) is a normal constituent of neuronal cell membranes. The protein misfolding causes rare neurodegenerative disorders known as transmissible spongiform encephalopathies or prion diseases. These maladies can be sporadic, genetic or infectious. Sporadic prion diseases are the most common form mainly affecting aging people. In this work, we investigate the biochemical environment in which sporadic prion diseases may develop, focusing our attention on the cell membrane of neurons in the aging brain. It is well established that with aging the ratio between the most abundant lipid components of rafts undergoes a major change: while cholesterol decreases, sphingomyelin content rises. Our results indicate that the aging process modifies the compartmentalization of PrP(C). In old mice, this change favors PrP(C) accumulation in detergent-resistant membranes, particularly in hippocampi. To confirm the relationship between lipid content changes and PrP(C) translocation into detergent-resistant membranes (DRMs), we looked at PrP(C) compartmentalization in hippocampi from acid sphingomyelinase (ASM) knockout (KO) mice and synaptosomes enriched in sphingomyelin. In the presence of high sphingomyelin content, we observed a significant increase of PrP(C) in DRMS. This process is not due to higher levels of total protein and it could, in turn, favor the onset of sporadic prion diseases during aging as it increases the PrP intermolecular contacts into lipid rafts. We observed that lowering sphingomyelin in scrapie-infected cells by using fumonisin B1 led to a 50% decrease in protease-resistant PrP formation. This may suggest an involvement of PrP lipid environment in prion formation and consequently it may play a role in the onset or development of sporadic forms of prion diseases. PMID:24040215

Agostini, Federica; Dotti, Carlos G; Pérez-Cañamás, Azucena; Ledesma, Maria Dolores; Benetti, Federico; Legname, Giuseppe

2013-09-10

108

Construction and Characterization of an Anti?Prion scFv Fusion Protein Pair for Detection of Prion Protein on Antibody Chip  

Microsoft Academic Search

A pair of single chain Fv fragment (scFv) fusion proteins were constructed and characterized. Antibody chips using the pair were designed for sensitive detection of prion protein. Phage displayed antibody library was synthesized by immunizing mice with thioredoxin?mature bovine prion fusion protein (TrxA?bPrP). After five rounds of panning against recombinant bovine prion protein (rb?PrP) and ELISA test, two positive clones

2007-01-01

109

Concentration-dependent Cu(II) binding to prion protein  

NASA Astrophysics Data System (ADS)

The prion protein plays a causative role in several neurodegenerative diseases, including mad cow disease in cattle and Creutzfeldt-Jakob disease in humans. The normal function of the prion protein is unknown, but it has been linked to its ability to bind copper ions. Experimental evidence suggests that copper can be bound in three distinct modes depending on its concentration, but only one of those binding modes has been fully characterized experimentally. Using a newly developed hybrid DFT/DFT method [1], which combines Kohn-Sham DFT with orbital-free DFT, we have examined all the binding modes and obtained their detailed binding geometries and copper ion binding energies. Our results also provide explanation for experiments, which have found that when the copper concentration increases the copper binding mode changes, surprisingly, from a stronger to a weaker one. Overall, our results indicate that prion protein can function as a copper buffer. 1. Hodak, Lu, Bernholc, JCP, in press.

Hodak, Miroslav; Lu, Wenchang; Bernholc, Jerry

2008-03-01

110

Role of a Novel Topological Form of a Prion Protein in Prion Disease.  

National Technical Information Service (NTIS)

Prion diseases are fatal neurological disorders of humans and other mammals. Prion diseases show an unusual etiology: they can arise from genetically, from infection through prion-contaminated food products, or sporadically. Most (but not all) cases of pr...

R. S. Stewart

2004-01-01

111

Prion Protein on Astrocytes or in Extracellular Fluid Impedes Neurodegeneration Induced by Truncated Prion Protein  

PubMed Central

Prion protein (PrP) is a host-encoded membrane-anchored glycoprotein which is required for susceptibility to prion disease. PrP may also be important for normal brain functions such as hippocampal spatial memory. Previously transgenic mice expressing amino terminally truncated mouse PrP (?32–134) spontaneously developed a fatal disease associated with degeneration of cerebellar granular neurons as well as vacuolar degeneration of deep cerebellar and brain stem white matter. This disease could be prevented by co-expression of wild-type (WT) mouse PrP on neurons or oligodendroglia. In the present experiments we studied ?32–134 PrP transgenic mice with WT PrP expression restricted to astroglia, an abundant CNS cell-type important for neuronal viability. Expression of WT PrP in astroglia was sufficient to rescue 50% of mice from disease and prolonged survival by 200 days in the other 50%. We also found that transgenic mice expressing full-length soluble anchorless PrP had increased survival by 100 days. Together these two results indicated that rescue from neurodegeneration induced by ?32–134 PrP might involve interactions between neurons expressing truncated PrP and nearby astrocytes expressing WT PrP or extracellular fluid containing soluble WT PrP.

Race, Brent; Meade-White, Kimberly; Race, Richard; Baumann, Frank; Aguzzi, Adriano; Chesebro, Bruce

2009-01-01

112

The controversial protein-only hypothesis of prion propagation  

Microsoft Academic Search

Prion diseases are some of the most intriguing infectious disorders affecting the brains of humans and animals. The prevalent hypothesis proposes that the infectious agent is a misfolded protein that propagates in the absence of nucleic acid by transmission of its altered folding to the normal host version of the protein. This article details the evidence for and against the

Joaquin Castilla; Claudio Soto

2004-01-01

113

Alpha2-macroglobulin is a potential facilitator of prion protein transformation.  

PubMed

Cellular prion protein changes conformation during transformation to an infectious scrapie isoform. One measure of transformation is the development of partial resistance to protease treatment. A fraction of human and bovine plasma was identified containing activity that facilitates transformation of cellular prion protein to a protease resistant isoform in the presence of RNA in the absence of seeded scrapie prion protein. Purification of proteins from this fraction led to the identification of alpha2-macroglobulin as an active component suggesting that it may facilitate conformational changes in prion protein in spontaneous forms of prion disease. PMID:17453620

Adler, Victor; Davidowitz, Eliot; Tamburi, Patricia; Rojas, Pedro; Grossman, Abraham

2007-03-01

114

Prions in Saccharomyces and Podospora spp.: Protein-Based Inheritance  

PubMed Central

Genetic evidence showed two non-Mendelian genetic elements of Saccharomyces cerevisiae, called [URE3] and [PSI], to be prions of Ure2p and Sup35p, respectively. [URE3] makes cells derepressed for nitrogen catabolism, while [PSI] elevates the efficiency of weak suppressor tRNAs. The same approach led to identification of the non-Mendelian element [Het-s] of the filamentous fungus Podospora anserina, as a prion of the het-s protein. The prion form of the het-s protein is required for heterokaryon incompatibility, a normal fungal function, suggesting that other normal cellular functions may be controlled by prions. [URE3] and [PSI] involve a self-propagating aggregation of Ure2p and Sup35p, respectively. In vitro, Ure2p and Sup35p form amyloid, a filamentous protein structure, high in ?-sheet with a characteristic green birefringent staining by the dye Congo Red. Amyloid deposits are a cardinal feature of Alzheimer’s disease, non-insulin-dependent diabetes mellitus, the transmissible spongiform encephalopathies, and many other diseases. The prion domain of Ure2p consists of Asn-rich residues 1 to 80, but two nonoverlapping fragments of the molecule can, when overproduced, induce the de nova appearance of [URE3]. The prion domain of Sup35 consists of residues 1 to 114, also rich in Asn and Gln residues. While runs of Asn and Gln are important for [URE3] and [PSI], no such structures are found in PrP or the Het-s protein. Either elevated or depressed levels of the chaperone Hsp104 interfere with propagation of [PSI]. Both [URE3] and [PSI] are cured by growth of cells in millimolar guanidine HCl. [URE3] is also cured by overexpression of fragments of Ure2p or fusion proteins including parts of Ure2p.

Wickner, Reed B.; Taylor, Kimberly L.; Edskes, Herman K.; Maddelein, Marie-Lise; Moriyama, Hiromitsu; Roberts, B. Tibor

1999-01-01

115

Humic substances interfere with detection of pathogenic prion protein  

USGS Publications Warehouse

Studies examining the persistence of prions (the etiological agent of transmissible spongiform encephalopathies) in soil require accurate quantification of pathogenic prion protein (PrPTSE) extracted from or in the presence of soil particles. Here, we demonstrate that natural organic matter (NOM) in soil impacts PrPTSE detection by immunoblotting. Methods commonly used to extract PrPTSE from soils release substantial amounts of NOM, and NOM inhibited PrPTSE immunoblot signal. The degree of immunoblot interference increased with increasing NOM concentration and decreasing NOM polarity. Humic substances affected immunoblot detection of prion protein from both deer and hamsters. We also establish that after interaction with humic acid, PrPTSE remains infectious to hamsters inoculated intracerebrally, and humic acid appeared to slow disease progression. These results provide evidence for interactions between PrPTSE and humic substances that influence both accurate measurement of PrPTSE in soil and disease transmission.

Smith, Christen B.; Booth, Clarissa J.; Wadzinski, Tyler J.; Legname, Giuseppe; Chappell, Rick; Johnson, Christopher J.; Pedersen, Joel A.

2014-01-01

116

Heat stability of prion rods and recombinant prion protein in water, lipid and lipid-water mixtures  

Microsoft Academic Search

Prion rods, i.e. insoluble infectious aggregates of the N-terminally truncated form of the prion protein, PrP 27-30, and the corresponding recombinant protein, rPrP(90-231), were autoclaved in water, bovine lipid or lipid-water mixtures for 20 min at temperatures from 100 to 170SC. A protocol was developed for the quantitative precipitation of small amounts of protein from large excesses of lipid. PrP

Thomas Raul Appel; Michael Wolff; Friedrich von Rheinbaben; Michael Heinzel; Detlev Riesner

2001-01-01

117

Prion induction involves an ancient system for the sequestration of aggregated proteins and heritable changes in prion fragmentation.  

PubMed

When the translation termination factor Sup35 adopts the prion state, [PSI(+)], the read-through of stop codons increases, uncovering hidden genetic variation and giving rise to new, often beneficial, phenotypes. Evidence suggests that prion induction involves a process of maturation, but this has never been studied in detail. To do so, we used a visually tractable prion model consisting of the Sup35 prion domain fused to GFP (PrD-GFP) and overexpressed it to achieve induction in many cells simultaneously. PrD-GFP first assembled into Rings as previously described. Rings propagated for many generations before the protein transitioned into a Dot structure. Dots transmitted the [PSI(+)] phenotype through mating and meiosis, but Rings did not. Surprisingly, the underlying amyloid conformation of PrD-GFP was identical in Rings and Dots. However, by electron microscopy, Rings consisted of very long uninterrupted bundles of fibers, whereas Dot fibers were highly fragmented. Both forms were deposited at the IPOD, a biologically ancient compartment for the deposition of irreversibly aggregated proteins that we propose is the site of de novo prion induction. We find that oxidatively damaged proteins are also localized there, helping to explain how proteotoxic stresses increase the rate of prion induction. Curing PrD-GFP prions, by inhibiting Hsp104's fragmentation activity, reversed the induction process: Dot cells produced Rings before PrD-GFP reverted to the soluble state. Thus, formation of the genetically transmissible prion state is a two-step process that involves an ancient system for the asymmetric inheritance of damaged proteins and heritable changes in the extent of prion fragmentation. PMID:20421488

Tyedmers, Jens; Treusch, Sebastian; Dong, Jijun; McCaffery, J Michael; Bevis, Brooke; Lindquist, Susan

2010-04-26

118

Analysis of the prion protein gene in thalamic dementia  

Microsoft Academic Search

Thalamic degenerations or dementias are poorly understood conditions. The familial forms are (1) selective thalamic degenerations and (2) thalamic degenerations associated with multiple system atrophy. Selective thalamic degenerations share clinical and pathologic features with fatal familial insomnia, an autosomal dominant disease linked to a mutation at codon 178 of the prion protein (PrP) gene that causes the substitution of asparagine

R. B. Petersen; M. Tabaton; L. Berg; B. Schrank; R. M. Torack; S. Leal; J. Julien; C. Vital; B. Deleplanque; W. W. Pendlebury; David A. Drachman

1992-01-01

119

Fatal Transmissible Amyloid Encephalopathy: A New Type of Prion Disease Associated with Lack of Prion Protein Membrane Anchoring  

Microsoft Academic Search

Prion diseases are fatal neurodegenerative diseases of humans and animals characterized by gray matter spongiosis and accumulation of aggregated, misfolded, protease-resistant prion protein (PrPres). PrPres can be deposited in brain in an amyloid-form and\\/or non-amyloid form, and is derived from host-encoded protease-sensitive PrP (PrPsen), a protein normally anchored to the plasma membrane by glycosylphosphatidylinositol (GPI). Previously, using heterozygous transgenic mice

Bruce Chesebro; Brent Race; Kimberly Meade-White; Rachel LaCasse; Richard Race; Mikael Klingeborn; James Striebel; David Dorward; Gillian McGovern; Martin Jeffrey

2010-01-01

120

Structural similarity between the prion domain of HET-s and a homologue can explain amyloid cross-seeding in spite of limited sequence identity.  

PubMed

We describe a distant homologue of the fungal HET-s prion, which is found in the fungus Fusarium graminearum. The domain FgHET-s(218-289), which corresponds to the prion domain in HET-s from Podospora anserina, forms amyloid fibrils in vitro and is able to efficiently cross-seed HET-s(218-289) prion formation. We structurally characterize FgHET-s(218-289), which displays 38% sequence identity with HET-s(218-289). Solid-state NMR and hydrogen/deuterium exchange detected by NMR show that the fold and a number of structural details are very similar for the prion domains of the two proteins. This structural similarity readily explains why cross-seeding occurs here in spite of the sequence divergence. PMID:20600104

Wasmer, Christian; Zimmer, Agnes; Sabaté, Raimon; Soragni, Alice; Saupe, Sven J; Ritter, Christiane; Meier, Beat H

2010-07-01

121

Prion Protein Modulates Cellular Iron Uptake: A Novel Function with Implications for Prion Disease Pathogenesis  

PubMed Central

Converging evidence leaves little doubt that a change in the conformation of prion protein (PrPC) from a mainly ?-helical to a ?-sheet rich PrP-scrapie (PrPSc) form is the main event responsible for prion disease associated neurotoxicity. However, neither the mechanism of toxicity by PrPSc, nor the normal function of PrPC is entirely clear. Recent reports suggest that imbalance of iron homeostasis is a common feature of prion infected cells and mouse models, implicating redox-iron in prion disease pathogenesis. In this report, we provide evidence that PrPC mediates cellular iron uptake and transport, and mutant PrP forms alter cellular iron levels differentially. Using human neuroblastoma cells as models, we demonstrate that over-expression of PrPC increases intra-cellular iron relative to non-transfected controls as indicated by an increase in total cellular iron, the cellular labile iron pool (LIP), and iron content of ferritin. As a result, the levels of iron uptake proteins transferrin (Tf) and transferrin receptor (TfR) are decreased, and expression of iron storage protein ferritin is increased. The positive effect of PrPC on ferritin iron content is enhanced by stimulating PrPC endocytosis, and reversed by cross-linking PrPC on the plasma membrane. Expression of mutant PrP forms lacking the octapeptide-repeats, the membrane anchor, or carrying the pathogenic mutation PrP102L decreases ferritin iron content significantly relative to PrPC expressing cells, but the effect on cellular LIP and levels of Tf, TfR, and ferritin is complex, varying with the mutation. Neither PrPC nor the mutant PrP forms influence the rate or amount of iron released into the medium, suggesting a functional role for PrPC in cellular iron uptake and transport to ferritin, and dysfunction of PrPC as a significant contributing factor of brain iron imbalance in prion disorders.

Isaac, Alfred Orina; Luo, Xiu; Petrak, Jiri; Vyoral, Daniel; Singh, Neena

2009-01-01

122

Doxycycline control of prion protein transgene expression modulates prion disease in mice  

PubMed Central

Conversion of the cellular prion protein (PrPC) into the pathogenic isoform (PrPSc) is the fundamental event underlying transmission and pathogenesis of prion diseases. To control the expression of PrPC in transgenic (Tg) mice, we used a tetracycline controlled transactivator (tTA) driven by the PrP gene control elements and a tTA-responsive promoter linked to a PrP gene [Gossen, M. and Bujard, H. (1992) Proc. Natl. Acad. Sci. USA 89, 5547–5551]. Adult Tg mice showed no deleterious effects upon repression of PrPC expression (>90%) by oral doxycycline, but the mice developed progressive ataxia at ?50 days after inoculation with prions unless maintained on doxycycline. Although Tg mice on doxycycline accumulated low levels of PrPSc, they showed no neurologic dysfunction, indicating that low levels of PrPSc can be tolerated. Use of the tTA system to control PrP expression allowed production of Tg mice with high levels of PrP that otherwise cause many embryonic and neonatal deaths. Measurement of PrPSc clearance in Tg mice should be possible, facilitating the development of pharmacotherapeutics.

Tremblay, Patrick; Meiner, Zeev; Galou, Maria; Heinrich, Cornelia; Petromilli, Chris; Lisse, Thomas; Cayetano, Juliana; Torchia, Marilyn; Mobley, William; Bujard, Hermann; DeArmond, Stephen J.; Prusiner, Stanley B.

1998-01-01

123

Dominant-Negative Inhibition of Prion Formation Diminished by Deletion Mutagenesis of the Prion Protein  

PubMed Central

Polymorphic basic residues near the C terminus of the prion protein (PrP) in humans and sheep appear to protect against prion disease. In heterozygotes, inhibition of prion formation appears to be dominant negative and has been simulated in cultured cells persistently infected with scrapie prions. The results of nuclear magnetic resonance and mutagenesis studies indicate that specific substitutions at the C-terminal residues 167, 171, 214, and 218 of PrPC act as dominant-negative, inhibitors of PrPSc formation (K. Kaneko et al., Proc. Natl. Acad. Sci. USA 94:10069–10074, 1997). Trafficking of substituted PrPC to caveaola-like domains or rafts by the glycolipid anchor was required for the dominant-negative phenotype; interestingly, amino acid replacements at multiple sites were less effective than single-residue substitutions. To elucidate which domains of PrPC are responsible for dominant-negative inhibition of PrPSc formation, we analyzed whether N-terminally truncated PrP(Q218K) molecules exhibited dominant-negative effects in the conversion of full-length PrPC to PrPSc. We found that the C-terminal domain of PrP is not sufficient to impede the conversion of the full-length PrPC molecule and that N-terminally truncated molecules (with residues 23 to 88 and 23 to 120 deleted) have reduced dominant-negative activity. Whether the N-terminal region of PrP acts by stabilizing the C-terminal domain of the molecule or by modulating the binding of PrPC to an auxiliary molecule that participates in PrPSc formation remains to be established.

Zulianello, Laurence; Kaneko, Kiyotoshi; Scott, Michael; Erpel, Susanne; Han, Dong; Cohen, Fred E.; Prusiner, Stanley B.

2000-01-01

124

Evidence for prion protein expression in enteroglial cells of the myenteric plexus of mouse intestine  

Microsoft Academic Search

Transmissible spongiform encephalopathies (TSEs) are slowly progressive and fatal neurodegenerative diseases affecting man and animals. They are caused by pathological isoforms (PrPSc) of the host-encoded cellular prion protein (PrPC). There are two crucial factors for the initiation of infection, namely host cells PrPC expression and sufficient sequence homology between the PrPSc to which the animal is exposed and its own

Valeria Albanese; Victoria A. Lawson; Andrew F. Hill; Roberto Cappai; Giovanni Di Guardo; Vasiliki Staikopoulos; Michelle Thacker; John B. Furness; Roberto Chiocchetti

2008-01-01

125

Expression of cellular prion protein (PrP c ) in schizophrenia, bipolar disorder, and depression  

Microsoft Academic Search

Cellular prion protein (PrPc) is a copper-binding, membrane-attached GPI-anchored glycoprotein characterized by a high degree of amino acid sequence conservation\\u000a among mammals. PrPc expression has been demonstrated in neurons, microglia, lymphocytes, and keratinocytes. Recently, the concept that PrPc may be involved in the defense against oxidative stress was advanced. In the present study, we used immunohistochemistry\\u000a for PrPc to investigate

Serge Weis; Johannes Haybaeck; Jeannette R. Dulay; Ida C. Llenos

2008-01-01

126

Prevalence of the prion protein gene E211K variant in U.S. cattle  

Microsoft Academic Search

BACKGROUND: In 2006, an atypical U.S. case of bovine spongiform encephalopathy (BSE) was discovered in Alabama and later reported to be polymorphic for glutamate (E) and lysine (K) codons at position 211 in the bovine prion protein gene (Prnp) coding sequence. A bovine E211K mutation is important because it is analogous to the most common pathogenic mutation in humans (E200K)

Michael P Heaton; John W Keele; Gregory P Harhay; Jürgen A Richt; Mohammad Koohmaraie; Tommy L Wheeler; Steven D Shackelford; Eduardo Casas; D Andy King; Tad S Sonstegard; Curtis P Van Tassell; Holly L Neibergs; Chad C Chase Jr; Theodore S Kalbfleisch; Timothy PL Smith; Michael L Clawson; William W Laegreid

2008-01-01

127

Synthetic peptide vaccines yield monoclonal antibodies to cellular and pathological prion proteins of ruminants  

Microsoft Academic Search

Transmissible spongiform encephalopathies are closely linked to the accumulation of a pathological isoform of a host-encoded prion protein (PrPC), designated PrPSc. In an attempt to generate mono- and polyclonal antibodies to ruminant PrP, 32 mice were vaccinated with peptide vaccines which were synthesized according to the amino acid sequence of ovine PrP. By this approach five PrP-reactive polyclonal antisera directed

Silke Harmeyer; Eberhard Pfaff; Martin H. Groschup

1998-01-01

128

Prion protein gene polymorphism in four West African sheep populations.  

PubMed

A total of 162 individuals, belonging to three Burkinabé and one Niger sheep populations, were analysed for prion protein (PrP) gene polymorphism at codons 136, 154 and 171. The ARQ allele was the most frequent in both the Burkinabé (86.7%) and the Niger (67.5%) sheep populations. The highly sensitive allele VRQ was not found in the sampled individuals. The highly resistant ARR allele was in very low frequency in the Burkina-Sahel (4.4%) and Mossi (3.2%) populations and was not present in the Djallonké and Touareg populations. Only 4 out of 15 possible PrP genotypes were identified in the sampled individuals. No favourable ARR/ARR genotypes were found in either of the breeds. Sequencing a subgroup of the samples allowed the identification of other five polymorphisms on the PrP gene sequence at codons 116, 138, 151, 237 and 240. The very low frequency of the ARR allele in the West African sheep should dissuade the implementation of a preventive selection programme aimed to increase resistance to scrapie, to avoid an extreme erosion of the genetic stock. PMID:22290502

Traoré, Amadou; Royo, Luis J; Kaboré, Adama; Pérez-Pardal, Lucía; Álvarez, Isabel; Fernández, Iván; Sawadogo, Laya; Tamboura, Hamidou H; Goyache, Félix

2012-10-01

129

Quaternary Structure of Pathological Prion Protein as a Determining Factor of Strain-Specific Prion Replication Dynamics  

PubMed Central

Prions are proteinaceous infectious agents responsible for fatal neurodegenerative diseases in animals and humans. They are essentially composed of PrPSc, an aggregated, misfolded conformer of the ubiquitously expressed host-encoded prion protein (PrPC). Stable variations in PrPSc conformation are assumed to encode the phenotypically tangible prion strains diversity. However the direct contribution of PrPSc quaternary structure to the strain biological information remains mostly unknown. Applying a sedimentation velocity fractionation technique to a panel of ovine prion strains, classified as fast and slow according to their incubation time in ovine PrP transgenic mice, has previously led to the observation that the relationship between prion infectivity and PrPSc quaternary structure was not univocal. For the fast strains specifically, infectivity sedimented slowly and segregated from the bulk of proteinase-K resistant PrPSc. To carefully separate the respective contributions of size and density to this hydrodynamic behavior, we performed sedimentation at the equilibrium and varied the solubilization conditions. The density profile of prion infectivity and proteinase-K resistant PrPSc tended to overlap whatever the strain, fast or slow, leaving only size as the main responsible factor for the specific velocity properties of the fast strain most infectious component. We further show that this velocity-isolable population of discrete assemblies perfectly resists limited proteolysis and that its templating activity, as assessed by protein misfolding cyclic amplification outcompetes by several orders of magnitude that of the bulk of larger size PrPSc aggregates. Together, the tight correlation between small size, conversion efficiency and duration of disease establishes PrPSc quaternary structure as a determining factor of prion replication dynamics. For certain strains, a subset of PrP assemblies appears to be the best template for prion replication. This has important implications for fundamental studies on prions.

Chapuis, Jerome; Sibille, Pierre; Herzog, Laetitia; Reine, Fabienne; Jaumain, Emilie; Laude, Hubert; Rezaei, Human; Beringue, Vincent

2013-01-01

130

Quaternary structure of pathological prion protein as a determining factor of strain-specific prion replication dynamics.  

PubMed

Prions are proteinaceous infectious agents responsible for fatal neurodegenerative diseases in animals and humans. They are essentially composed of PrP(Sc), an aggregated, misfolded conformer of the ubiquitously expressed host-encoded prion protein (PrP(C)). Stable variations in PrP(Sc) conformation are assumed to encode the phenotypically tangible prion strains diversity. However the direct contribution of PrP(Sc) quaternary structure to the strain biological information remains mostly unknown. Applying a sedimentation velocity fractionation technique to a panel of ovine prion strains, classified as fast and slow according to their incubation time in ovine PrP transgenic mice, has previously led to the observation that the relationship between prion infectivity and PrP(Sc) quaternary structure was not univocal. For the fast strains specifically, infectivity sedimented slowly and segregated from the bulk of proteinase-K resistant PrP(Sc). To carefully separate the respective contributions of size and density to this hydrodynamic behavior, we performed sedimentation at the equilibrium and varied the solubilization conditions. The density profile of prion infectivity and proteinase-K resistant PrP(Sc) tended to overlap whatever the strain, fast or slow, leaving only size as the main responsible factor for the specific velocity properties of the fast strain most infectious component. We further show that this velocity-isolable population of discrete assemblies perfectly resists limited proteolysis and that its templating activity, as assessed by protein misfolding cyclic amplification outcompetes by several orders of magnitude that of the bulk of larger size PrP(Sc) aggregates. Together, the tight correlation between small size, conversion efficiency and duration of disease establishes PrP(Sc) quaternary structure as a determining factor of prion replication dynamics. For certain strains, a subset of PrP assemblies appears to be the best template for prion replication. This has important implications for fundamental studies on prions. PMID:24130496

Laferrière, Florent; Tixador, Philippe; Moudjou, Mohammed; Chapuis, Jérôme; Sibille, Pierre; Herzog, Laetitia; Reine, Fabienne; Jaumain, Emilie; Laude, Hubert; Rezaei, Human; Béringue, Vincent

2013-10-10

131

The HET-s Prion Protein of the Filamentous Fungus Podospora anserina Aggregates in Vitro into Amyloid-like Fibrils  

Microsoft Academic Search

The HET-s protein of Podospora anserina is a fungal prion. This protein behaves as an infectious cytoplasmic element that is transmitted horizontally from one strain to another. Under the prion form, the HET-s protein forms aggregates in vivo. The specificity of this prion model compared with the yeast prions resides in the fact that under the prion form HET-s causes

Suzana Dos Reis; Vincent Forge; Joel Begueret; Sven J. Saupe; Universitede Bordeaux

2002-01-01

132

Phosphorylation of prion protein at serine 43 induces prion protein conformational change.  

PubMed

The cause of the conformational change of normal cellular prion protein (PrP) into its disease-associated form is unknown. Posttranslational modifications, such as glycosylation, acetylation, S-nitrosylation, and phosphorylation, are known to induce protein conformational changes. Here, we investigated whether phosphorylation could induce the conformational change of PrP because PrP contains several kinase motifs and has been found recently in the cytosol, in which kinases generally reside. Neuronal cyclin-dependent kinase 5 (Cdk5) phosphorylated recombinant PrP(23-231) at serine 43 (S43) in an in vitro kinase assay. Cdk5-phosphorylated PrP became proteinase K resistant, formed Congo Red-positive fibrils, and formed aggregates that were immunostained with anti-PrP and anti-phospho-PrP(S43) (anti-pPrP(S43)). pPrP(S43) was detected in PrP/Cdk5/p25 cotransfected N2a cells. Roscovitine inhibition of Cdk5 activity or transfection of N2a cells with mutant PrP S43A eliminated the anti-pPrP(S43)-immunopositive protein. Alkaline phosphatase-sensitive and proteinase K-resistant pPrP(S43) immunoreactivity was observed in scrapie-infected but not control-injected mice brains. These results raise the possibility that phosphorylation could represent a physiological mechanism of PrP conversion in vivo. PMID:19587281

Giannopoulos, Paresa N; Robertson, Catherine; Jodoin, Julie; Paudel, Hemant; Booth, Stephanie A; LeBlanc, Andrea C

2009-07-01

133

Amyloids and yeast prion biology.  

PubMed

The prions (infectious proteins) of Saccharomyces cerevisiae are proteins acting as genes, by templating their conformation from one molecule to another in analogy to DNA templating its sequence. Most yeast prions are amyloid forms of normally soluble proteins, and a single protein sequence can have any of several self-propagating forms (called prion strains or variants), analogous to the different possible alleles of a DNA gene. A central issue in prion biology is the structural basis of this conformational templating process. The in-register parallel ? sheet structure found for several infectious yeast prion amyloids naturally suggests an explanation for this conformational templating. While most prions are plainly diseases, the [Het-s] prion of Podospora anserina may be a functional amyloid, with important structural implications. Yeast prions are important models for human amyloid diseases in general, particularly because new evidence is showing infectious aspects of several human amyloidoses not previously classified as prions. We also review studies of the roles of chaperones, aggregate-collecting proteins, and other cellular components using yeast that have led the way in improving the understanding of similar processes that must be operating in many human amyloidoses. PMID:23379365

Wickner, Reed B; Edskes, Herman K; Bateman, David A; Kelly, Amy C; Gorkovskiy, Anton; Dayani, Yaron; Zhou, Albert

2013-02-12

134

Similar folds with different stabilization mechanisms: the cases of prion and doppel proteins  

PubMed Central

Background Protein misfolding is the main cause of a group of fatal neurodegenerative diseases in humans and animals. In particular, in Prion-related diseases the normal cellular form of the Prion Protein PrP (PrPC) is converted into the infectious PrPSc through a conformational process during which it acquires a high ?-sheet content. Doppel is a protein that shares a similar native fold, but lacks the scrapie isoform. Understanding the molecular determinants of these different behaviours is important both for biomedical and biophysical research. Results In this paper, the dynamical and energetic properties of the two proteins in solution is comparatively analyzed by means of long time scale explicit solvent, all-atom molecular dynamics in different temperature conditions. The trajectories are analyzed by means of a recently introduced energy decomposition approach (Tiana et al, Prot. Sci. 2004) aimed at identifying the key residues for the stabilization and folding of the protein. Our analysis shows that Prion and Doppel have two different cores stabilizing the native state and that the relative contribution of the nucleus to the global stability of the protein for Doppel is sensitively higher than for PrP. Moreover, under misfolding conditions the Doppel core is conserved, while the energy stabilization network of PrP is disrupted. Conclusion These observations suggest that different sequences can share similar native topology with different stabilizing interactions and that the sequences of the Prion and Doppel proteins may have diverged under different evolutionary constraints resulting in different folding and stabilization mechanisms.

Colacino, Stefano; Tiana, Guido; Colombo, Giorgio

2006-01-01

135

Circumventing Tolerance to Generate Autologous Monoclonal Antibodies to the Prion Protein  

NASA Astrophysics Data System (ADS)

Prion diseases are disorders of protein conformation and do not provoke an immune response. Raising antibodies to the prion protein (PrP) has been difficult due to conservation of the PrP sequence and to inhibitory activity of ? -PrP antibodies toward lymphocytes. To circumvent these problems, we immunized mice in which the PrP gene was ablated (Prnp0/0) and retrieved specific monoclonal antibodies (mAbs) through phage display libraries. This approach yielded ? -PrP mAbs that recognize mouse PrP. Studies with these mAbs suggest that cellular PrP adopts an unusually open structure consistent with the conformational plasticity of this protein.

Williamson, R. Anthony; Peretz, David; Smorodinsky, Nechama; Bastidas, Raiza; Serban, Hana; Mehlhorn, Ingrid; Dearmond, Stephen J.; Prusiner, Stanley B.; Burton, Dennis R.

1996-07-01

136

The effect of ?2-?2 loop mutation on amyloidogenic properties of the prion protein.  

PubMed

Recent studies revealed that elk-like S170N/N174T mutation in mouse prion protein (moPrP), which results in an increased rigidity of ?2-?2 loop, leads to a prion disease in transgenic mice. Here we characterized the effect of this mutation on biophysical properties of moPrP. Despite similar thermodynamic stabilities of wild type and mutant proteins, the latter was found to have markedly higher propensity to form amyloid fibrils. Importantly, this effect was observed even under fully denaturing conditions, indicating that the increased conversion propensity of the mutant protein is not due to loop rigidity but rather results from greater amyloidogenic potential of the amino acid sequence within the loop region of S170N/N174T moPrP. PMID:23892077

Dutta, Arpana; Chen, Shugui; Surewicz, Witold K

2013-07-24

137

Kinetics of ozone inactivation of infectious prion protein.  

PubMed

The kinetics of ozone inactivation of infectious prion protein (PrP(Sc), scrapie 263K) was investigated in ozone-demand-free phosphate-buffered saline (PBS). Diluted infectious brain homogenates (IBH) (0.01%) were exposed to a predetermined ozone dose (10.8 ± 2.0 mg/liter) at three pHs (pH 4.4, 6.0, and 8.0) and two temperatures (4°C and 20°C). The inactivation of PrP(Sc) was quantified by determining the in vitro destruction of PrP(Sc) templating properties using the protein misfolding cyclic amplification (PMCA) assay and bioassay, which were shown to correlate well. The inactivation kinetics were characterized by both Chick-Watson (CW) and efficiency factor Hom (EFH) models. It was found that the EFH model fit the experimental data more appropriately. The efficacy of ozone inactivation of PrP(Sc) was both pH and temperature dependent. Based on the EFH model, CT (disinfectant concentration multiplied by contact time) values were determined for 2-log10, 3-log10, and 4-log10 inactivation at the conditions under which they were achieved. Our results indicated that ozone is effective for prion inactivation in ozone-demand-free water and may be applied for the inactivation of infectious prion in prion-contaminated water and wastewater. PMID:23416994

Ding, Ning; Neumann, Norman F; Price, Luke M; Braithwaite, Shannon L; Balachandran, Aru; Mitchell, Gordon; Belosevic, Miodrag; Gamal El-Din, Mohamed

2013-02-15

138

Prion protein degradation by lichens of the genus Cladonia  

USGS Publications Warehouse

It has recently been discovered that lichens contain a serine protease capable of degrading the pathogenic prion protein, the etiological agent of prion diseases such as sheep scrapie and cervid chronic wasting disease. Limited methods are available to degrade or inactivate prion disease agents, especially in the environment, and lichens or their serine protease could prove important for management of these diseases. Scant information is available regarding the presence or absence of the protease responsible for degrading prion protein (PrP) in lichen species and, in this study, we tested the hypothesis that PrP degradation activity in lichens is phylogenetically-based by testing 44 species of Cladonia lichens, a genus for which a significant portion of the phylogeny is well established. We categorized PrP degradation activity among the 44 species (high, moderate, low or none) and found that activity in Cladonia species did not correspond with phylogenetic position of the species. Degradation of PrP did correspond, however, with three classical taxonomic characters within the genus: species with brown apothecia, no usnic acid, and the presence of a cortex. Of the 44 species studied, 18 (41%) had either high or moderate PrP degradation activity, suggesting the protease may be frequent in this genus of lichens.

Bennett, James P.; Rodriguez, Cynthia M.; Johnson, Christopher J.

2012-01-01

139

Kinetics of Ozone Inactivation of Infectious Prion Protein  

PubMed Central

The kinetics of ozone inactivation of infectious prion protein (PrPSc, scrapie 263K) was investigated in ozone-demand-free phosphate-buffered saline (PBS). Diluted infectious brain homogenates (IBH) (0.01%) were exposed to a predetermined ozone dose (10.8 ± 2.0 mg/liter) at three pHs (pH 4.4, 6.0, and 8.0) and two temperatures (4°C and 20°C). The inactivation of PrPSc was quantified by determining the in vitro destruction of PrPSc templating properties using the protein misfolding cyclic amplification (PMCA) assay and bioassay, which were shown to correlate well. The inactivation kinetics were characterized by both Chick-Watson (CW) and efficiency factor Hom (EFH) models. It was found that the EFH model fit the experimental data more appropriately. The efficacy of ozone inactivation of PrPSc was both pH and temperature dependent. Based on the EFH model, CT (disinfectant concentration multiplied by contact time) values were determined for 2-log10, 3-log10, and 4-log10 inactivation at the conditions under which they were achieved. Our results indicated that ozone is effective for prion inactivation in ozone-demand-free water and may be applied for the inactivation of infectious prion in prion-contaminated water and wastewater.

Ding, Ning; Price, Luke M.; Braithwaite, Shannon L.; Balachandran, Aru; Mitchell, Gordon; Belosevic, Miodrag

2013-01-01

140

CELL BIOLOGY: Sowing the Protein Seeds of Prion Propagation  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. Ever since Prusiner first proposed his radical "protein-only" hypothesis to explain how certain infectious proteins (prions) are transmitted from one mammal to another in the absence of DNA or RNA, scientists have been trying to prove him right (or wrong). The study of mammalian prions, such as those causing Creutzfeldt-Jakob disease in humans, scrapie in sheep and mad cow disease in cattle, has been slow to yield answers. However, as Tuite discusses in his Perspective, the Sup35p and Ure2p proteins of yeast that exist in both normal and infectious forms are providing evidence that the "protein-only" hypothesis may be right (Sparrer et al.).

Mick F. Tuite (University of Kent;Department of Biosciences)

2000-07-28

141

Clearance of yeast prions by misfolded multi-transmembrane proteins.  

PubMed

Accumulation of misfolded proteins in the endoplasmic reticulum (ER) induces the stress response to protect cells against toxicity by the unfolded protein response (UPR), heat shock response (HSR), and ER-associated degradation pathways. Here, we found that over-production of C-terminally truncated multi-transmembrane (MTM) mutant proteins triggers HSR, but not UPR, and clearance of yeast prions [PSI(+)] and [URE3]. One of the mutant MTM proteins, Dip5?C-v82, produces a disabled amino-acid permease. Fluorescence microscopy analysis revealed abnormal accumulation of Dip5?C-v82 in the ER. Importantly, the mutant defective in the GET pathway, which functions for ER membrane insertion of tail-anchored proteins, failed to translocate Dip5?C-v82 to the ER and disabled Dip5?C-v82-mediated prion clearance. These findings suggest that the GET pathway plays a pivotal role in quality assurance of MTM proteins, and entraps misfolded MTM proteins into ER compartments, leading to loss-of-prion through a yet undefined mechanism. PMID:23384482

Arai, Chie; Kurahashi, Hiroshi; Ishiwata, Masao; Oishi, Keita; Nakamura, Yoshikazu

2013-02-04

142

Cellular prion protein promotes invasion and metastasis of gastric cancer  

Microsoft Academic Search

Cellular prion protein (PrPc) is a glyco- sylphosphatidylinositol (GPI) -anchored membrane protein that is highly conserved in mammalian species. PrPc has the characteristics of adhesive molecules and is thought to play a role in cell adhesion and membrane signaling. Here we investigated the possible role of PrPc in the process of invasiveness and metastasis in gastric cancers. PrPc was found

Yanglin Pan; Lina Zhao; Jie Liang; Jie Liu; Yongquan Shi; Na Liu; Guoyun Zhang; Haifeng Jin; Juan Gao; Huahong Xie; Jun Wang; Zhiguo Liu; Daiming Fan

2006-01-01

143

The Landscape of the Prion Protein's Structural Response to Mutation Revealed by Principal Component Analysis of Multiple NMR Ensembles  

Microsoft Academic Search

Prion Proteins (PrP) are among a small number of proteins for which large numbers of NMR ensembles have been resolved for sequence mutants and diverse species. Here, we perform a comprehensive principle components analysis (PCA) on the tertiary structures of PrP globular proteins to discern PrP subdomains that exhibit conformational change in response to point mutations and clade-specific evolutionary sequence

Deena M. A. Gendoo; Paul M. Harrison

2012-01-01

144

Lithium induces clearance of protease resistant prion protein in prion-infected cells by induction of autophagy.  

PubMed

Lithium is used for several decades to treat manic-depressive illness (bipolar affective disorder). Recently, it was found that lithium induces autophagy, thereby promoting the clearance of mutant huntingtin and alpha-synucleins in experimental systems. We show here for the first time that lithium significantly reduces the amount of pathological prion protein (PrP(Sc)) in prion-infected neuronal and non-neuronal cultured cells by inducing autophagy. Treatment of prion-infected cells with 3-methyladenine, a potent inhibitor of autophagy, counteracted the anti-prion effect of lithium, demonstrating that induction of autophagy mediates degradation of PrP(Sc). Co-treatment with lithium and rapamycin, a drug widely used to induce autophagy, had an additive effect on PrP(Sc) clearance compared to treatment with either drug alone. In addition, we provide evidence that the ability to reduce PrP(Sc) and to induce autophagy is common for diverse lithium compounds, not only for the drug lithium chloride, usually administered in clinical therapy. Furthermore, we show here that besides reduction of PrP(Sc)-aggregates, lithium-induced autophagy also slightly reduces the levels of cellular prion protein. Limiting the substrate available for conversion of cellular prion protein into PrP(Sc) may provide an additional mechanism for reduction of PrP(Sc) by lithium-induced autophagy. PMID:19183256

Heiseke, Andreas; Aguib, Yasmine; Riemer, Constanze; Baier, Michael; Schätzl, Hermann M

2009-02-20

145

Conversion of a yeast prion protein to an infectious form in bacteria  

PubMed Central

Prions are infectious, self-propagating protein aggregates that have been identified in evolutionarily divergent members of the eukaryotic domain of life. Nevertheless, it is not yet known whether prokaryotes can support the formation of prion aggregates. Here we demonstrate that the yeast prion protein Sup35 can access an infectious conformation in Escherichia coli cells and that formation of this material is greatly stimulated by the presence of a transplanted [PSI+] inducibility factor, a distinct prion that is required for Sup35 to undergo spontaneous conversion to the prion form in yeast. Our results establish that the bacterial cytoplasm can support the formation of infectious prion aggregates, providing a heterologous system in which to study prion biology.

Garrity, Sean J.; Sivanathan, Viknesh; Dong, Jijun; Lindquist, Susan; Hochschild, Ann

2010-01-01

146

BSE Case Associated with Prion Protein Gene Mutation  

PubMed Central

Bovine spongiform encephalopathy (BSE) is a transmissible spongiform encephalopathy (TSE) of cattle and was first detected in 1986 in the United Kingdom. It is the most likely cause of variant Creutzfeldt-Jakob disease (CJD) in humans. The origin of BSE remains an enigma. Here we report an H-type BSE case associated with the novel mutation E211K within the prion protein gene (Prnp). Sequence analysis revealed that the animal with H-type BSE was heterozygous at Prnp nucleotides 631 through 633. An identical pathogenic mutation at the homologous codon position (E200K) in the human Prnp has been described as the most common cause of genetic CJD. This finding represents the first report of a confirmed case of BSE with a potential pathogenic mutation within the bovine Prnp gene. A recent epidemiological study revealed that the K211 allele was not detected in 6062 cattle from commercial beef processing plants and 42 cattle breeds, indicating an extremely low prevalence of the E211K variant (less than 1 in 2000) in cattle.

Richt, Jurgen A.; Hall, S. Mark

2008-01-01

147

The Role of Activity in Synaptic Degeneration in a Protein Misfolding Disease, Prion Disease  

PubMed Central

In chronic neurodegenerative diseases associated with aggregates of misfolded proteins (such as Alzheimer's, Parkinson's and prion disease), there is an early degeneration of presynaptic terminals prior to the loss of the neuronal somata. Identifying the mechanisms that govern synapse degeneration is of paramount importance, as cognitive decline is strongly correlated with loss of presynaptic terminals in these disorders. However, very little is known about the processes that link the presence of a misfolded protein to the degeneration of synapses. It has been suggested that the process follows a simple linear sequence in which terminals that become dysfunctional are targeted for death, but there is also evidence that high levels of activity can speed up degeneration. To dissect the role of activity in synapse degeneration, we infused the synaptic blocker botulinum neurotoxin A (BoNT/A) into the hippocampus of mice with prion disease and assessed synapse loss at the electron microscopy level. We found that injection of BoNT/A in naïve mice caused a significant enlargement of excitatory presynaptic terminals in the hippocampus, indicating transmission impairment. Long-lasting blockade of activity by BoNT/A caused only minimal synaptic pathology and no significant activation of microglia. In mice with prion disease infused with BoNT/A, rates of synaptic degeneration were indistinguishable from those observed in control diseased mice. We conclude that silencing synaptic activity neither prevents nor enhances the degree of synapse degeneration in prion disease. These results challenge the idea that dysfunction of synaptic terminals dictates their elimination during prion-induced neurodegeneration.

Vannini, Eleonora; Siskova, Zuzana; Al-Malki, Hussain; Morgan, Ruth; O'Connor, Vincent; Perry, V. Hugh

2012-01-01

148

Recombinant full-length murine prion protein, mPrP(23–231): purification and spectroscopic characterization  

Microsoft Academic Search

The cellular prion protein of the mouse, mPrPC, consists of 208 amino acids (residues 23–231). It contains a carboxy-terminal domain, mPrP(121–231), which represents an autonomous folding unit with three ?-helices and a two-stranded antiparallel ?-sheet. We expressed the complete amino acid sequence of the prion protein, mPrP(23–231), in the cytoplasm of Escherichia coli. mPrP(23–231) was solubilized from inclusion bodies by

Simone Hornemann; Carsten Korth; Bruno Oesch; Roland Riek; Gerhard Wider; Kurt Wüthrich; Rudi Glockshuber

1997-01-01

149

Identification of a Protein that Purifies with the Scrapie Prion  

NASA Astrophysics Data System (ADS)

Purification of prions from scrapie-infected hamster brain yielded a protein that was not found in a similar fraction from uninfected brain. The protein migrated with an apparent molecular size of 27,000 to 30,000 daltons in sodium dodecyl sulfate polyacrylamide gels. The resistance of this protein to digestion by proteinase K distinguished it from proteins of similar molecular weight found in normal hamster brain. Initial results suggest that the amount of this protein correlates with the titer of the agent.

Bolton, David C.; McKinley, Michael P.; Prusiner, Stanley B.

1982-12-01

150

Transition-metal prion protein attachment: Competition with copper  

NASA Astrophysics Data System (ADS)

Prion protein, PrP, is a protein capable of binding copper ions in multiple modes depending on their concentration. Misfolded PrP is implicated in a group of neurodegenerative diseases, which include ``mad cow disease'' and its human form, variant Creutzfeld-Jacob disease. An increasing amount of evidence suggests that attachment of non-copper metal ions to PrP triggers transformations to abnormal forms similar to those observed in prion diseases. In this work, we use hybrid Kohn-Sham/orbital-free density functional theory simulations to investigate copper replacement by other transition metals that bind to PrP, including zinc, iron and manganese. We consider all known copper binding modes in the N-terminal domain of PrP. Our calculations identify modes most susceptible to copper replacement and reveal metals that can successfully compete with copper for attachment to PrP.

Hodak, Miroslav; Bernholc, Jerry

2012-02-01

151

Copper and the Prion Protein: Methods, Structures, Function, and Disease  

NASA Astrophysics Data System (ADS)

The transmissible spongiform encephalopathies (TSEs) arise from conversion of the membrane-bound prion protein from PrPC to PrPSc. Examples of the TSEs include mad cow disease, chronic wasting disease in deer and elk, scrapie in goats and sheep, and kuru and Creutzfeldt-Jakob disease in humans. Although the precise function of PrPC in healthy tissues is not known, recent research demonstrates that it binds Cu(II) in an unusual and highly conserved region of the protein termed the octarepeat domain. This review describes recent connections between copper and PrPC, with an emphasis on the electron paramagnetic resonance elucidation of the specific copper-binding sites, insights into PrPC function, and emerging connections between copper and prion disease.

Millhauser, Glenn L.

2007-05-01

152

Development of Monoclonal Antibodies Specific for Glycated Prion Protein  

Microsoft Academic Search

Transmissive spongiform encephalopathies (TSE) are neurodegenerative diseases characterized by depositions of abnormally folded prion protein (PrP) in brain. PrP is at present the only specific biochemical marker of human and animal TSE. As deposits of PrP remain in the body for long periods, there is substantial chance of them being nonenzymatically modified by glycation. The detection of glycated PrP may

Eva Dvorakova; Marek Prouza; Olga Janouskova; Martin Panigaj; Karel Holada

2011-01-01

153

Prion protein detection in serum using micromechanical resonator arrays  

Microsoft Academic Search

Prion proteins that have transformed from their normal cellular counterparts (PrPc) into infectious form (PrPres) are responsible for causing progressive neurodegenerative diseases in numerous species, such as bovine spongiform encephalopathy (BSE) in cattle (also known as mad cow disease), scrapie in sheep, and Creutzfeldt–Jakob disease (CJD) in humans. Due to a possible link between BSE and CJD it is highly

Madhukar Varshney; Philip S. Waggoner; Richard A. Montagna; Harold G. Craighead

2009-01-01

154

Polythiophenes Inhibit Prion Propagation by Stabilizing Prion Protein (PrP) Aggregates*  

PubMed Central

Luminescent conjugated polymers (LCPs) interact with ordered protein aggregates and sensitively detect amyloids of many different proteins, suggesting that they may possess antiprion properties. Here, we show that a variety of anionic, cationic, and zwitterionic LCPs reduced the infectivity of prion-containing brain homogenates and of prion-infected cerebellar organotypic cultured slices and decreased the amount of scrapie isoform of PrPC (PrPSc) oligomers that could be captured in an avidity assay. Paradoxically, treatment enhanced the resistance of PrPSc to proteolysis, triggered the compaction, and enhanced the resistance to proteolysis of recombinant mouse PrP(23–231) fibers. These results suggest that LCPs act as antiprion agents by transitioning PrP aggregates into structures with reduced frangibility. Moreover, ELISA on cerebellar organotypic cultured slices and in vitro conversion assays with mouse PrP(23–231) indicated that poly(thiophene-3-acetic acid) may additionally interfere with the generation of PrPSc by stabilizing the conformation of PrPC or of a transition intermediate. Therefore, LCPs represent a novel class of antiprion agents whose mode of action appears to rely on hyperstabilization, rather than destabilization, of PrPSc deposits.

Margalith, Ilan; Suter, Carlo; Ballmer, Boris; Schwarz, Petra; Tiberi, Cinzia; Sonati, Tiziana; Falsig, Jeppe; Nystrom, Sofie; Hammarstrom, Per; Aslund, Andreas; Nilsson, K. Peter R.; Yam, Alice; Whitters, Eric; Hornemann, Simone; Aguzzi, Adriano

2012-01-01

155

Soluble Prion Protein Inhibits Amyloid-? (A?) Fibrillization and Toxicity*  

PubMed Central

The pathogenesis of Alzheimer disease appears to be strongly linked to the aggregation of amyloid-? (A?) peptide and, especially, formation of soluble A?1–42 oligomers. It was recently demonstrated that the cellular prion protein, PrPC, binds with high affinity to these oligomers, acting as a putative receptor that mediates at least some of their neurotoxic effects. Here we show that the soluble (i.e. glycophosphatidylinositol anchor-free) prion protein and its N-terminal fragment have a strong effect on the aggregation pathway of A?1–42, inhibiting its assembly into amyloid fibrils. Furthermore, the prion protein prevents formation of spherical oligomers that normally occur during A? fibrillogenesis, acting as a potent inhibitor of A?1–42 toxicity as assessed in experiments with neuronal cell culture. These findings may provide a molecular level foundation to explain the reported protective action of the physiologically released N-terminal N1 fragment of PrPC against A? neurotoxicity. They also suggest a novel approach to pharmacological intervention in Alzheimer disease.

Nieznanski, Krzysztof; Choi, Jin-Kyu; Chen, Shugui; Surewicz, Krystyna; Surewicz, Witold K.

2012-01-01

156

Surface charge of polyoxometalates modulates polymerization of the scrapie prion protein  

Microsoft Academic Search

Prions are composed solely of an alternatively folded isoform of the prion protein (PrP), designated PrPSc. N-terminally truncated PrPSc, denoted PrP 27-30, retains infectivity and polymerizes into rods with the ultrastructural and tinctorial properties of amyloid. We report here that some polyoxometalates (POMs) favor polymerization of PrP 27-30 into prion rods, whereas other POMs promote assembly of the protein into

Holger Wille; Maheswaran Shanmugam; Muralee Murugesu; Julian Ollesch; Gerald Stubbs; Jeffrey R. Long; Jiri G. Safar

2009-01-01

157

Molecular genetics of human prion diseases in Germany  

Microsoft Academic Search

Human prion diseases may be acquired as infectious diseases, they may be inherited in an autosomal dominant fashion or occur sporadically. Mutations and polymorphisms in the sequence of the coding region of the prion protein gene (PRNP) have been established as an important factor in all of these three types of prion diseases. Therefore, a total of 578 patients with

O. Windl; A. Giese; W. Schulz-Schaeffer; I. Zerr; K. Skworc; S. Arendt; C. Oberdieck; M. Bodemer; S. Poser; H. A. Kretzschmar

1999-01-01

158

Clinicopathologic characteristics of sporadic Japanese Creutzfeldt–Jakob disease classified according to prion protein gene polymorphism and prion protein type  

Microsoft Academic Search

We analyzed neuropathologic features of 23 Japanese patients with sporadic Creutzfeldt–Jakob disease (sCJD) by means of prion protein (PrP) immunolabeling associated with codon 129 polymorphism of the PrP gene and western blot analysis of protease-resistant PrP (PrP type). Clinical features, particularly age at onset, disease duration, periodic synchronous discharge and presence of myoclonus, were also analyzed. This study included 11

Yasushi Iwasaki; Mari Yoshida; Yoshio Hashizume; Tetsuyuki Kitamoto; Gen Sobue

2006-01-01

159

Higher susceptibility to amyloid fibril formation of the recombinant ovine prion protein modified by transglutaminase.  

PubMed

Prion proteins are known as the main agents of transmissible spongiform encephalopathies affecting humans as well as animals. A recombinant ovine prion protein was found to be in vitro able to act as an effective substrate for a microbial isoform of transglutaminase, an enzyme catalyzing the formation of isopeptide bonds inside the proteins. We proved that transglutaminase modifies the structure of the prion protein by leading to the formation of three intra-molecular crosslinks and that the crosslinked protein form is more competent in amyloid formation compared to the unmodified one. In addition, the crosslinked prion protein was shown also to be more resistant to proteinase K digestion. Our findings suggest a possible use of transglutaminase in stabilizing the prion protein three-dimensional structure in order to investigate the molecular basis of the conversion of the protein into its pathological form. PMID:22705206

Sorrentino, Angela; Giosafatto, Concetta Valeria L; Sirangelo, Ivana; De Simone, Carmela; Di Pierro, Prospero; Porta, Raffaele; Mariniello, Loredana

2012-06-13

160

Isolation of novel synthetic prion strains by amplification in transgenic mice coexpressing wild-type and anchorless prion proteins.  

PubMed

Mammalian prions are thought to consist of misfolded aggregates (protease-resistant isoform of the prion protein [PrP(res)]) of the cellular prion protein (PrP(C)). Transmissible spongiform encephalopathy (TSE) can be induced in animals inoculated with recombinant PrP (rPrP) amyloid fibrils lacking mammalian posttranslational modifications, but this induction is inefficient in hamsters or transgenic mice overexpressing glycosylphosphatidylinositol (GPI)-anchored PrP(C). Here we show that TSE can be initiated by inoculation of misfolded rPrP into mice that express wild-type (wt) levels of PrP(C) and that synthetic prion strain propagation and selection can be affected by GPI anchoring of the host's PrP(C). To create prions de novo, we fibrillized mouse rPrP in the absence of molecular cofactors, generating fibrils with a PrP(res)-like protease-resistant banding profile. These fibrils induced the formation of PrP(res) deposits in transgenic mice coexpressing wt and GPI-anchorless PrP(C) (wt/GPI(-)) at a combined level comparable to that of PrP(C) expression in wt mice. Secondary passage into mice expressing wt, GPI(-), or wt plus GPI(-) PrP(C) induced TSE disease with novel clinical, histopathological, and biochemical phenotypes. Contrary to laboratory-adapted mouse scrapie strains, the synthetic prion agents exhibited a preference for conversion of GPI(-) PrP(C) and, in one case, caused disease only in GPI(-) mice. Our data show that novel TSE agents can be generated de novo solely from purified mouse rPrP after amplification in mice coexpressing normal levels of wt and anchorless PrP(C). These observations provide insight into the minimal elements required to create prions in vitro and suggest that the PrP(C) GPI anchor can modulate the propagation of synthetic TSE strains. PMID:22915801

Raymond, Gregory J; Race, Brent; Hollister, Jason R; Offerdahl, Danielle K; Moore, Roger A; Kodali, Ravindra; Raymond, Lynne D; Hughson, Andrew G; Rosenke, Rebecca; Long, Dan; Dorward, David W; Baron, Gerald S

2012-08-22

161

Rapid cell-surface prion protein conversion revealed using a novel cell system  

PubMed Central

Prion diseases are fatal neurodegenerative disorders with unique transmissible properties. The infectious and pathological agent is thought to be a misfolded conformer of the prion protein. Little is known about the initial events in prion infection because the infecting prion source has been immunologically indistinguishable from normal cellular prion protein (PrPC). Here we develop a unique cell system in which epitope-tagged PrPC is expressed in a PrP knockdown (KD) neuroblastoma cell line. The tagged PrPC, when expressed in our PrP-KD cells, supports prion replication with the production of bona fide epitope-tagged infectious misfolded PrP (PrPSc). Using this epitope-tagged PrPSc, we study the earliest events in cellular prion infection and PrP misfolding. We show that prion infection of cells is extremely rapid occurring within 1 min of prion exposure, and we demonstrate that the plasma membrane is the primary site of prion conversion.

Goold, R.; Rabbanian, S.; Sutton, L.; Andre, R.; Arora, P.; Moonga, J.; Clarke, A.R.; Schiavo, G.; Jat, P.; Collinge, J.; Tabrizi, S.J.

2011-01-01

162

Alzheimer Disease and the Prion Disorders Amyloid ?-Protein and Prion Protein Amyloidoses  

NASA Astrophysics Data System (ADS)

Alzheimer disease and the prion disorders/spongiform encephalopathies share many common features. These chronic, progressive, sometimes familial diseases of the central nervous system are characterized by the presence of different types of amyloid deposits in the brain. This review provides a perspective on these two types of neurodegenerative disorders.

Price, Donald L.; Borchelt, David R.; Sisodia, Sangram S.

1993-07-01

163

Molecular dynamics studies on the structural stability of wild-type dog prion protein.  

PubMed

Prion diseases such as Creutzfeldt-Jakob disease, variant Creutzfeldt-Jakob diseases, Gerstmann-Sträussler-Scheinker syndrome, Fatal Familial Insomnia, Kuru in humans, scrapie in sheep, bovine spongiform encephalopathy (or 'mad-cow' disease) and chronic wasting disease in cattle are invariably fatal and highly infectious neurodegenerative diseases affecting humans and animals. However, by now there have not been some effective therapeutic approaches to treat all these prion diseases. In 2008, canine mammals including dogs (canis familials) were the first time academically reported to be resistant to prion diseases (Vaccine 26: 2601-2614 (2008)). Thus, it is very worth studying the molecular structures of dog prion protein to obtain insights into the immunity of dogs to prion diseases. This paper studies the molecular structural dynamics of wild-type dog prion protein. The comparison analyses with rabbit prion protein show that the dog prion protein has stable molecular structures whether under neutral or low pH environments. We also find that the salt bridges such as D177-R163 contribute to the structural stability of wild-type rabbit prion protein under neutral pH environment. PMID:21469747

Zhang, Jiapu; Liu, David D W

2011-06-01

164

Characterizing affinity epitopes between prion protein and ?-amyloid using an epitope mapping immunoassay  

PubMed Central

Cellular prion protein, a membrane protein, is expressed in all mammals. Prion protein is also found in human blood as an anchorless protein, and this protein form is one of the many potential sources of misfolded prion protein replication during transmission. Many studies have suggested that ?-amyloid1–42 oligomer causes neurotoxicity associated with Alzheimer's disease, which is mediated by the prion protein that acts as a receptor and regulates the hippocampal potentiation. The prevention of the binding of these proteins has been proposed as a possible preventative treatment for Alzheimer's disease; therefore, a greater understanding of the binding hot-spots between the two molecules is necessary. In this study, the epitope mapping immunoassay was employed to characterize binding epitopes within the prion protein and complementary epitopes in ?-amyloid. Residues 23–39 and 93–119 in the prion protein were involved in binding to ?-amyloid1–40 and 1–42, and monomers of this protein interacted with prion protein residues 93–113 and 123–166. Furthermore, ?-amyloid antibodies against the C-terminus detected bound ?-amyloid1–42 at residues 23–40, 104–122 and 159–175. ?-Amyloid epitopes necessary for the interaction with prion protein were not determined. In conclusion, charged clusters and hydrophobic regions of the prion protein were involved in binding to ?-amyloid1–40 and 1–42. The 3D structure appears to be necessary for ?-amyloid to interact with prion protein. In the future, these binding sites may be utilized for 3D structure modeling, as well as for the pharmaceutical intervention of Alzheimer's disease.

Kang, Mino; Kim, Su Yeon; An, Seong Soo A; Ju, Young Ran

2013-01-01

165

Prion diseases of yeast: amyloid structure and biology.  

PubMed

Prion "variants" or "strains" are prions with the identical protein sequence, but different characteristics of the prion infection: e.g. different incubation periods for scrapie strains or different phenotype intensities for yeast prion variants. We have shown that infectious amyloids of the yeast prions [PSI+], [URE3] and [PIN+] each have an in-register parallel ?-sheet architecture. Moreover, we have pointed out that this amyloid architecture can explain how one protein can faithfully transmit any of several conformations to new protein monomers. This explains how proteins can be genes. PMID:21345375

Wickner, Reed B; Edskes, Herman K; Kryndushkin, Dmitry; McGlinchey, Ryan; Bateman, David; Kelly, Amy

2011-02-21

166

Visual detection of prion protein based on color complementarity principle.  

PubMed

Two complementary colors mixed in a proper proportion will produce a neutral color in the color theory. A novel colorimetric method on basis of the color complementarity principle has been well-established to detect recombinant prion protein (rPrP). We found that a colorless solution appeared after mixing orange CdTe quantum dots (QDs) with green-blue malachite green (MG) because of color complementarity. After the addition of rPrP into the mixed solution, the color changed from colorless to green-blue because rPrP could induce the aggregation of QDs, rapidly. And it could be observed by naked eyes. Based on this phenomenon, we developed a simple assay for visual detection of rPrP. At the same time, we obtained excellent correlation between absorption and concentrations of rPrP from 1nmolL(-1) to 78nmolL(-1) with the limit of detection of 0.3nmolL(-1) (3?). Moreover, it can be applied to determine rPrP in human serum successfully. Importantly, this assay possesses the advantages of simplicity, rapidity, sensitivity, and selectivity, and shows the potential in the clinical diagnostic test of early prion disease and provides the possibility of preventing the spread of prion diseases. PMID:23827372

Liang, Liping; Long, Yijuan; Zhang, Haijie; Wang, Qinlong; Huang, Xiaoxiao; Zhu, Rui; Teng, Ping; Wang, Xiliang; Zheng, Huzhi

2013-06-18

167

In Vitro and In Vivo Neurotoxicity of Prion Protein Oligomers  

PubMed Central

The mechanisms underlying prion-linked neurodegeneration remain to be elucidated, despite several recent advances in this field. Herein, we show that soluble, low molecular weight oligomers of the full-length prion protein (PrP), which possess characteristics of PrP to PrPsc conversion intermediates such as partial protease resistance, are neurotoxic in vitro on primary cultures of neurons and in vivo after subcortical stereotaxic injection. Monomeric PrP was not toxic. Insoluble, fibrillar forms of PrP exhibited no toxicity in vitro and were less toxic than their oligomeric counterparts in vivo. The toxicity was independent of PrP expression in the neurons both in vitro and in vivo for the PrP oligomers and in vivo for the PrP fibrils. Rescue experiments with antibodies showed that the exposure of the hydrophobic stretch of PrP at the oligomeric surface was necessary for toxicity. This study identifies toxic PrP species in vivo. It shows that PrP-induced neurodegeneration shares common mechanisms with other brain amyloidoses like Alzheimer disease and opens new avenues for neuroprotective intervention strategies of prion diseases targeting PrP oligomers.

Simoneau, Steve; Rezaei, Human; Sales, Nicole; Kaiser-Schulz, Gunnar; Lefebvre-Roque, Maxime; Vidal, Catherine; Fournier, Jean-Guy; Comte, Julien; Wopfner, Franziska; Grosclaude, Jeanne; Schatzl, Hermann; Lasmezas, Corinne Ida

2007-01-01

168

Unique quadruplex structure and interaction of an RNA aptamer against bovine prion protein  

PubMed Central

RNA aptamers against bovine prion protein (bPrP) were obtained, most of the obtained aptamers being found to contain the r(GGAGGAGGAGGA) (R12) sequence. Then, it was revealed that R12 binds to both bPrP and its ?-isoform with high affinity. Here, we present the structure of R12. This is the first report on the structure of an RNA aptamer against prion protein. R12 forms an intramolecular parallel quadruplex. The quadruplex contains G:G:G:G tetrad and G(:A):G:G(:A):G hexad planes. Two quadruplexes form a dimer through intermolecular hexad–hexad stacking. Two lysine clusters of bPrP have been identified as binding sites for R12. The electrostatic interaction between the uniquely arranged phosphate groups of R12 and the lysine clusters is suggested to be responsible for the affinity of R12 to bPrP. The stacking interaction between the G:G:G:G tetrad planes and tryptophan residues may also contribute to the affinity. One R12 dimer molecule is supposed to simultaneously bind the two lysine clusters of one bPrP molecule, resulting in even higher affinity. The atomic coordinates of R12 would be useful for the development of R12 as a therapeutic agent against prion diseases and Alzheimer's disease.

Mashima, Tsukasa; Matsugami, Akimasa; Nishikawa, Fumiko; Nishikawa, Satoshi; Katahira, Masato

2009-01-01

169

Labeling of the scrapie-associated prion protein in vitro and in vivo  

Microsoft Academic Search

Prion diseases are a group of infectious neurodegenerative diseases that affect both animals and humans. A characteristic of prion diseases is the aggregation and accumulation of a disease-associated isoform of the prion protein in the brains of infected individuals. The amyloid imaging probe (trans,trans)-1-bromo-2,5-bis-(3-hydroxycarbonyl-4-hydroxy)styrylbenzene (BSB) has shown potential in the diagnosis of other amyloid disorders and we hypothesized that this

Valerie B. Hoefert; Judd M. Aiken; Debbie McKenzie; Christopher J. Johnson

2004-01-01

170

Genetic influence on the structural variations of the abnormal prion protein  

Microsoft Academic Search

Prion diseases are characterized by the presence of the abnormal prion protein PrPSc, which is believed to be generated by the conversion of the -helical structure that predominates in the normal PrP isoform into a -sheet structure resistant to proteinase K (PK). In human prion diseases, two major types of PrPSc, type 1 and 2, can be distinguished based on

Piero Parchi; Wenquan Zou; Wen Wang; Paul Brown; Sabina Capellari; Bernardino Ghetti; Nicolas Kopp; Walter J. Schulz-Schaeffer; Hans A. Kretzschmar; Mark W. Head; James W. Ironside; Pierluigi Gambetti; Shu G. Chen

2000-01-01

171

Atypical prion protein in sheep brain collected during the British scrapie-surveillance programme  

Microsoft Academic Search

Scrapie of sheep and goats is the most common prion disease (or transmissible spongiform encephalopathy, TSE) of mammals and aggregates of abnormal, proteinase-resistant prion protein (PrPSc) are found in all naturally occurring prion diseases. During active surveillance of British sheep for TSEs, 29201 sheep brain stem samples were collected from abattoirs and analysed for the presence of PrPSc. Of these

S. J. Everest; L. Thorne; D. A. Barnicle; J. C. Edwards; H. Elliott; R. Jackman; J. Hope

2006-01-01

172

Sleep and Sleep Regulation in Normal and Prion Protein-Deficient Mice  

Microsoft Academic Search

Mice are the preferred mammalian species for genetic investi- gations of the role of proteins. The normal function of the prion protein (PrP) is unknown, although it plays a major role in the prion diseases, including fatal familial insomnia. We investi- gated its role in sleep and sleep regulation by comparing baseline recordings and the effects of sleep deprivation in

Irene Tobler; Tom Deboer; Marek Fischer

1997-01-01

173

Stability of bovine spongiform encephalopathy prions: absence of prion protein degradation by bovine gut microbiota.  

PubMed

Bovine spongiform encephalopathy (BSE) is transmitted by the oral route. However, the impacts of anaerobic fermentation processes in cattle on the stability of BSE-associated prion protein (PrP(Sc)) are still unresolved. In this study, experiments were designed to assess the ability of complex ruminal and colonic contents of bovines to degrade BSE-derived PrP(Sc). No significant decrease in PrP(Sc) levels in BSE brain homogenates was detected by Western blotting after up to 66 h of co-incubation with intestinal fluids. These results indicate that BSE-associated PrP(Sc) survive gastrointestinal digestion processes in cattle and might be excreted via faeces. PMID:22353543

Böhnlein, C; Groschup, M H; Maertlbauer, E; Pichner, R; Gareis, M

2012-02-21

174

New Molecular Insights into Cellular Survival and Stress Responses: Neuroprotective Role of Cellular Prion Protein (PrP C )  

Microsoft Academic Search

Knowledge of the physiological function of cellular prion protein has been acquired from prion diseases such as Creutzfeldt–Jakob\\u000a disease, as well as PRNP knock out and transgenic mice. Recent progress in neurobiology has further delineated the neuroprotective\\u000a role played by cellular prion protein. In this paper, we review the role of cellular prion protein in cell survival including\\u000a its antiapoptotic

Raymond Yen-Yu Lo; Woei-Cherng Shyu; Shinn-Zong Lin; Hsiao-Jung Wang; Shun-Sheng Chen; Hung Li

2007-01-01

175

Distinct Stability States of Disease-Associated Human Prion Protein Identified by Conformation-Dependent Immunoassay?  

PubMed Central

The phenotypic and strain-related properties of human prion diseases are, according to the prion hypothesis, proposed to reside in the physicochemical properties of the conformationally altered, disease-associated isoform of the prion protein (PrPSc), which accumulates in the brains of patients suffering from Creutzfeldt-Jakob disease and related conditions, such as Gerstmann-Straussler-Scheinker disease. Molecular strain typing of human prion diseases has focused extensively on differences in the fragment size and glycosylation site occupancy of the protease-resistant prion protein (PrPres) in conjunction with the presence of mutations and polymorphisms in the prion protein gene (PRNP). Here we report the results of employing an alternative strategy that specifically addresses the conformational stability of PrPSc and that has been used previously to characterize animal prion strains transmitted to rodents. The results show that there are at least two distinct conformation stability states in human prion diseases, neither of which appears to correlate fully with the PrPres type, as judged by fragment size or glycosylation, the PRNP codon 129 status, or the presence or absence of mutations in PRNP. These results suggest that conformational stability represents a further dimension to a complete description of potentially phenotype-related properties of PrPSc in human prion diseases.

Choi, Young Pyo; Peden, Alexander H.; Groner, Albrecht; Ironside, James W.; Head, Mark W.

2010-01-01

176

Analyses of Protease Resistance and Aggregation State of Abnormal Prion Protein across the Spectrum of Human Prions.  

PubMed

Prion diseases are characterized by tissue accumulation of a misfolded, ?-sheet-enriched isoform (scrapie prion protein (PrP(Sc))) of the cellular prion protein (PrP(C)). At variance with PrP(C), PrP(Sc) shows a partial resistance to protease digestion and forms highly aggregated and detergent-insoluble polymers, two properties that have been consistently used to distinguish the two proteins. In recent years, however, the idea that PrP(Sc) itself comprises heterogeneous species has grown. Most importantly, a putative proteinase K (PK)-sensitive form of PrP(Sc) (sPrP(Sc)) is being increasingly investigated for its possible role in prion infectivity, neurotoxicity, and strain variability. The study of sPrP(Sc), however, remains technically challenging because of the need of separating it from PrP(C) without using proteases. In this study, we have systematically analyzed both PK resistance and the aggregation state of purified PrP(Sc) across the whole spectrum of the currently characterized human prion strains. The results show that PrP(Sc) isolates manifest significant strain-specific differences in their PK digestion profile that are only partially explained by differences in the size of aggregates, suggesting that other factors, likely acting on PrP(Sc) aggregate stability, determine its resistance to proteolysis. Fully protease-sensitive low molecular weight aggregates were detected in all isolates but in a limited proportion of the overall PrP(Sc) (i.e. <10%), arguing against a significant role of slowly sedimenting PK-sensitive PrP(Sc) in the biogenesis of prion strains. Finally, we highlight the limitations of current operational definitions of sPrP(Sc) and of the quantitative analytical measurements that are not based on the isolation of a fully PK-sensitive PrP(Sc) form. PMID:23897825

Saverioni, Daniela; Notari, Silvio; Capellari, Sabina; Poggiolini, Ilaria; Giese, Armin; Kretzschmar, Hans A; Parchi, Piero

2013-07-29

177

Cloning and polymorphism analysis of prion protein gene in domestic bactrian camel in China.  

PubMed

Up to now, little is known about the prion protein gene (PRNP) of domestic bactrian camels, and no polymorphisms of the bactrian camel PRNP have been analyzed or reported. In this study, we cloned and analyzed the PRNP sequences of 89 domestic bactrian camels. The results showed that the amino acid sequence of bactrian camel PrP starts with the consensus sequence MVKSH, with almost identical amino acid sequence to the PrP of dromedary camels. A four octapeptide PHGGGWGQ repeat region follows a nonapeptide (PQGGGGWGQ) in the N-terminal of deduced amino acid sequence from residues 54 to 95. Polymorphisms of PRNP in both species of camels were observed in codons 16(A?V), 17(M?T), 120(N?S), 176(R?K), 215(I?V), 234(S?Y), 237(Y?S), and 239(Q?G) by comparing with other ruminants. The PrP gene nucleotide sequence alignments of bactrian camels (HQ204566.1 and HQ204567.1) showed high identity with dromedary camel (99.2%, 99.1%), sheep (91.9%, 91.8%) and cattle (91.8%, 91.6%). This study provides valuable data for future research on susceptibility or resistance of camels to prion diseases. PMID:22019430

Xu, Lihua; Zhang, Zhuming; Wang, Ling; Feng, Dengzhen; Zhou, Xiangmei; Xu, Binrui; Zhao, Deming

2011-10-13

178

Comparative genomic analysis of prion genes  

Microsoft Academic Search

BACKGROUND: The homologues of human disease genes are expected to contribute to better understanding of physiological and pathogenic processes. We made use of the present availability of vertebrate genomic sequences, and we have conducted the most comprehensive comparative genomic analysis of the prion protein gene PRNP and its homologues, shadow of prion protein gene SPRN and doppel gene PRND, and

Marko Premzl; Vera Gamulin

2007-01-01

179

High CJD infectivity remains after prion protein is destroyed  

PubMed Central

The hypothesis that host prion protein (PrP) converts into an infectious prion form rests on the observation that infectivity progressively decreases in direct proportion to the decrease of PrP with proteinase K (PK) treatment. PrP that resists limited PK digestion (PrP-res, PrPsc) has been assumed to be the infectious form, with speculative types of misfolding encoding the many unique TSE agent strains. Recently, a PK sensitive form of PrP has been proposed as the prion. Thus we re-evaluated total PrP (sensitive and resistant) and used a cell-based assay for titration of infectious particles. A keratinase (NAP) known to effectively digest PrP was compared to PK. Total PrP in FU-CJD infected brain was reduced to ?0.3% in a 2hr PK digest, yet there was no reduction in titer. Remaining non-PrP proteins were easily visualized with colloidal gold in this highly infectious homogenate. In contrast to PK, NAP digestion left 0.8% residual PrP after 2hr, yet decreased titer by >2.5logs; few residual protein bands remained. FU-CJD infected cells with 10x the infectivity of brain by both animal and cell culture assays were also evaluated. NAP again significantly reduced cell infectivity (>3.5 logs). Extreme PK digestions were needed to reduce cell PrP to <0.2%, yet a very high titer of ?7.8 logs remained. Our FU-CJD brain results are in good accord with the only other report on maximal PrP digestion and titer. It is likely that one or more residual non-PrP proteins may protect agent nucleic acids in infectious particles.

Miyazawa, Kohtaro; Emmerling, Kaitlin; Manuelidis, Laura

2011-01-01

180

A Promiscuous Prion: Efficient Induction of [URE3] Prion Formation by Heterologous Prion Domains  

PubMed Central

The [URE3] and [PSI+] prions are the infections amyloid forms of the Saccharomyces cerevisiae proteins Ure2p and Sup35p, respectively. Randomizing the order of the amino acids in the Ure2 and Sup35 prion domains while retaining amino acid composition does not block prion formation, indicating that amino acid composition, not primary sequence, is the predominant feature driving [URE3] and [PSI+] formation. Here we show that Ure2p promiscuously interacts with various compositionally similar proteins to influence [URE3] levels. Overexpression of scrambled Ure2p prion domains efficiently increases de novo formation of wild-type [URE3] in vivo. In vitro, amyloid aggregates of the scrambled prion domains efficiently seed wild-type Ure2p amyloid formation, suggesting that the wild-type and scrambled prion domains can directly interact to seed prion formation. To test whether interactions between Ure2p and naturally occurring yeast proteins could similarly affect [URE3] formation, we identified yeast proteins with domains that are compositionally similar to the Ure2p prion domain. Remarkably, all but one of these domains were also able to efficiently increase [URE3] formation. These results suggest that a wide variety of proteins could potentially affect [URE3] formation.

Ross, Carley D.; McCarty, Blake R.; Hamilton, Michael; Ben-Hur, Asa; Ross, Eric D.

2009-01-01

181

The Hofmeister effect on amyloid formation using yeast prion protein.  

PubMed

A variety of proteins are capable of converting from their soluble forms into highly ordered fibrous cross-beta aggregates (amyloids). This conversion is associated with certain pathological conditions in mammals, such as Alzheimer disease, and provides a basis for the infectious or hereditary protein isoforms (prions), causing neurodegenerative disorders in mammals and controlling heritable phenotypes in yeast. The N-proximal region of the yeast prion protein Sup35 (Sup35NM) is frequently used as a model system for amyloid conversion studies in vitro. Traditionally, amyloids are recognized by their ability to bind Congo Red dye specific to beta-sheet rich structures. However, methods for quantifying amyloid fibril formation thus far were based on measurements linking Congo Red absorbance to concentration of insulin fibrils and may not be directly applicable to other amyloid-forming proteins. Here, we present a corrected formula for measuring amyloid formation of Sup35NM by Congo Red assay. By utilizing this corrected procedure, we explore the effect of different sodium salts on the lag time and maximum rate of amyloid formation by Sup35NM. We find that increased kosmotropicity promotes amyloid polymerization in accordance with the Hofmeister series. In contrast, chaotropes inhibit polymerization, with the strength of inhibition correlating with the B-viscosity coefficient of the Jones-Dole equation, an increasingly accepted measure for the quantification of the Hofmeister series. PMID:19890987

Yeh, Victor; Broering, James M; Romanyuk, Andrey; Chen, Buxin; Chernoff, Yury O; Bommarius, Andreas S

2010-01-01

182

Prion Protein Is Necessary for Latent Learning and Long-Term Memory Retention  

Microsoft Academic Search

1. The cellular prion protein, designated PrPc, is a key molecule in the prion diseases but its physiological function remains unknown. To elucidate whether PrPc plays some role in the central nervous system, we established a line of mice in which the PrP gene had been disrupted and subsequently conducted long-term observations.

Noriyuki Nishida; Shigeru Katamine; Kazuto Shigematsu; Akira Nakatani; Nobuhiro Sakamoto; Sumitaka Hasegawa; Ryota Nakaoke; Ryuichiro Atarashi; Yasufumi Kataoka; Tsutomu Miyamoto

1997-01-01

183

A reassessment of copper(II) binding in the full-length prion protein  

PubMed Central

It has been shown previously that the unfolded N-terminal domain of the prion protein can bind up to six Cu2+ ions in vitro. This domain contains four tandem repeats of the octapeptide sequence PHGGGWGQ, which, alongside the two histidine residues at positions 96 and 111, contribute to its Cu2+ binding properties. At the maximum metal-ion occupancy each Cu2+ is co-ordinated by a single imidazole and deprotonated backbone amide groups. However two recent studies of peptides representing the octapeptide repeat region of the protein have shown, that at low Cu2+ availability, an alternative mode of co-ordination occurs where the metal ion is bound by multiple histidine imidazole groups. Both modes of binding are readily populated at pH 7.4, while mild acidification to pH 5.5 selects in favour of the low occupancy, multiple imidazole binding mode. We have used NMR to resolve how Cu2+ binds to the full-length prion protein under mildly acidic conditions where multiple histidine co-ordination is dominant. We show that at pH 5.5 the protein binds two Cu2+ ions, and that all six histidine residues of the unfolded N-terminal domain and the N-terminal amine act as ligands. These two sites are of sufficient affinity to be maintained in the presence of millimolar concentrations of competing exogenous histidine. A previously unknown interaction between the N-terminal domain and a site on the C-terminal domain becomes apparent when the protein is loaded with Cu2+. Furthermore, the data reveal that sub-stoichiometric quantities of Cu2+ will cause self-association of the prion protein in vitro, suggesting that Cu2+ may play a role in controlling oligomerization in vivo.

Wells, Mark A.; Jackson, Graham S.; Jones, Samantha; Hosszu, Laszlo L. P.; Craven, C. Jeremy; Clarke, Anthony R.; Collinge, John; Waltho, Jonathan P.

2006-01-01

184

Prion protein inhibits microtubule assembly by inducing tubulin oligomerization  

SciTech Connect

A growing body of evidence points to an association of prion protein (PrP) with microtubular cytoskeleton. Recently, direct binding of PrP to tubulin has also been found. In this work, using standard light scattering measurements, sedimentation experiments, and electron microscopy, we show for First time the effect of a direct interaction between these proteins on tubulin polymerization. We demonstrate that full-length recombinant PrP induces a rapid increase in the turbidity of tubulin diluted below the critical concentration for microtubule assembly. This effect requires magnesium ions and is weakened by NaCl. Moreover, the PrP-induced light scattering structures of tubulin are cold-stable. In preparations of diluted tubulin incubated with PrP, electron microscopy revealed the presence of {approx}50 nm disc-shaped structures not reported so far. These unique tubulin oligomers may form large aggregates. The effect of PrP is more pronounced under the conditions promoting microtubule formation. In these tubulin samples, PrP induces formation of the above oligomers associated with short protofilaments and sheets of protofilaments into aggregates. Noticeably, this is accompanied by a significant reduction of the number and length of microtubules. Hence, we postulate that prion protein may act as an inhibitor of microtubule assembly by inducing formation of stable tubulin oligomers.

Nieznanski, Krzysztof [Nencki Institute of Experimental Biology, Department of Muscle Biochemistry, Warsaw (Poland)]. E-mail: k.nieznanski@nencki.gov.pl; Podlubnaya, Zoya A. [Institute of Theoretical and Experimental Biophysics, Laboratory of Structure and Function of Muscle Proteins, Pushchino (Russian Federation); Pushchino State University, Pushchino (Russian Federation); Nieznanska, Hanna [Nencki Institute of Experimental Biology, Department of Muscle Biochemistry, Warsaw (Poland)

2006-10-13

185

Biological Roles of Prion Domains  

PubMed Central

In vivo amyloid formation is a widespread phenomenon in eukaryotes. Self-perpetuating amyloids provide a basis for the infectious or heritable protein isoforms (prions). At least for some proteins, amyloid-forming potential is conserved in evolution despite divergence of the amino acid (aa) sequences. In some cases, prion formation certainly represents a pathological process leading to a disease. However, there are several scenarios in which prions and other amyloids or amyloid-like aggregates are either shown or suspected to perform positive biological functions. Proven examples include self/nonself recognition, stress defense and scaffolding of other (functional) polymers. The role of prion-like phenomena in memory has been hypothesized. As an additional mechanism of heritable change, prion formation may in principle contribute to heritable variability at the population level. Moreover, it is possible that amyloid-based prions represent by-products of the transient feedback regulatory circuits, as normal cellular function of at least some prion proteins is decreased in the prion state.

Inge-Vechtomov, Sergey G; Zhouravleva, Galina A

2007-01-01

186

SSCP analysis and sequencing of the human prion protein gene (PRNP) detects two different 24 bp deletions in an atypical Alzheimer`s disease family  

Microsoft Academic Search

Alzheimer`s disease (AD) is a progressive, degenerative neurological disorder of the central nervous system. AD is the fourth leading cause of death in elderly persons 65 years or older in Western industrialized societies. The etiology of AD is unknown, but clinical, pathological, epidemiological, and molecular investigations suggest it is etiologically heterogeneous. Mutations in the amyloid protein are rare and segregate

R. T. Perry; R. C. P. Go; L. E. Harrell; R. T. Acton

1995-01-01

187

Cellular prion protein modulates ?-amyloid deposition in aged APP/PS1 transgenic mice.  

PubMed

Alzheimer's disease and prion diseases are neuropathological disorders that are caused by abnormal processing and aggregation of amyloid and prion proteins. Interactions between amyloid precursor protein (APP) and PrP(c) proteins have been described at the neuron level. Accordingly to this putative interaction, we investigated whether ?-amyloid accumulation may affect prion infectivity and, conversely, whether different amounts of PrP may affect ?-amyloid accumulation. For this purpose, we used the APPswe/PS1dE9 mouse line, a common model of Alzheimer's disease, crossed with mice that either overexpress (Tga20) or that lack prion protein (knock-out) to generate mice that express varying amounts of prion protein and deposit ?-amyloid. On these mouse lines, we investigated the influence of each protein on the evolution of both diseases. Our results indicated that although the presence of APP/PS1 and ?-amyloid accumulation had no effect on prion infectivity, the accumulation of ?-amyloid deposits was dependent on PrP(c), whereby increasing levels of prion protein were accompanied by a significant increase in ?-amyloid aggregation associated with aging. PMID:23831375

Ordóñez-Gutiérrez, Lara; Torres, Juan María; Gavín, Rosalina; Antón, Marta; Arroba-Espinosa, Ana Isabel; Espinosa, Juan-Carlos; Vergara, Cristina; Del Río, José A; Wandosell, Francisco

2013-07-04

188

Follicular Dendritic Cell-Specific Prion Protein (PrPc) Expression Alone Is Sufficient to Sustain Prion Infection in the Spleen  

PubMed Central

Prion diseases are characterised by the accumulation of PrPSc, an abnormally folded isoform of the cellular prion protein (PrPC), in affected tissues. Following peripheral exposure high levels of prion-specific PrPSc accumulate first upon follicular dendritic cells (FDC) in lymphoid tissues before spreading to the CNS. Expression of PrPC is mandatory for cells to sustain prion infection and FDC appear to express high levels. However, whether FDC actively replicate prions or simply acquire them from other infected cells is uncertain. In the attempts to-date to establish the role of FDC in prion pathogenesis it was not possible to dissociate the Prnp expression of FDC from that of the nervous system and all other non-haematopoietic lineages. This is important as FDC may simply acquire prions after synthesis by other infected cells. To establish the role of FDC in prion pathogenesis transgenic mice were created in which PrPC expression was specifically “switched on” or “off” only on FDC. We show that PrPC-expression only on FDC is sufficient to sustain prion replication in the spleen. Furthermore, prion replication is blocked in the spleen when PrPC-expression is specifically ablated only on FDC. These data definitively demonstrate that FDC are the essential sites of prion replication in lymphoid tissues. The demonstration that Prnp-ablation only on FDC blocked splenic prion accumulation without apparent consequences for FDC status represents a novel opportunity to prevent neuroinvasion by modulation of PrPC expression on FDC.

McCulloch, Laura; Brown, Karen L.; Bradford, Barry M.; Hopkins, John; Bailey, Mick; Rajewsky, Klaus; Manson, Jean C.; Mabbott, Neil A.

2011-01-01

189

Accumulation of Pathological Prion Protein PrPSc in the Skin of Animals with Experimental and Natural Scrapie  

Microsoft Academic Search

Prion infectivity and its molecular marker, the pathological prion protein PrPSc, accumulate in the central nervous system and often also in lymphoid tissue of animals or humans affected by transmissible spongiform encephalopathies. Recently, PrPSc was found in tissues previously considered not to be invaded by prions (e.g., skeletal muscles). Here, we address the question of whether prions target the skin

Achim Thomzig; Walter Schulz-Schaeffer; Arne Wrede; Wilhelm Wemheuer; Bertram Brenig; Christine Kratzel; Karin Lemmer; Michael Beekes

2007-01-01

190

Identification of a Prion Protein Epitope Modulating Transmission of Bovine Spongiform Encephalopathy Prions to Transgenic Mice  

Microsoft Academic Search

There is considerable concern that bovine prions from cattle with bovine spongiform encephalopathy (BSE) may have been passed to humans (Hu), resulting in a new form of Creutzfeldt-Jakob disease (CJD). We report here the transmission of bovine (Bo) prions to transgenic (Tg) mice expressing BoPrP; one Tg line exhibited incubation times of ≈ 200 days. Like most cattle with BSE,

Michael R. Scott; Jiri Safar; Glenn Telling; Oanh Nguyen; Darlene Groth; Marilyn Torchia; Ruth Koehler; Patrick Tremblay; Dirk Walther; Fred E. Cohen; Stephen J. Dearmond

1997-01-01

191

Stressing Out the ER: A Role of the Unfolded Protein Response in Prion-Related Disorders  

PubMed Central

Transmissible Spongiform Encephalopathies are fatal and infectious neurodegenerative diseases characterized by extensive neuronal apoptosis and the accumulation of an abnormally folded form of the cellular prion protein (PrP), denoted PrPSC. Compelling evidence suggests the involvement of several signaling pathways in prion pathogenesis, including proteasome dysfunction, alterations in the protein maturation pathways and the unfolded protein response. Recent reports indicate that endoplasmic reticulum stress due to the PrP misfolding may be a critical factor mediating neuronal dysfunction in prion diseases. These findings have applications for developing novel strategies for treatment and early diagnosis of transmissible spongiform encephalopathies and other neurodegenerative diseases.

Hetz, Claudio A.; Soto, Claudio

2009-01-01

192

Identification of a prion protein epitope modulating transmission of bovine spongiform encephalopathy prions to transgenic mice  

PubMed Central

There is considerable concern that bovine prions from cattle with bovine spongiform encephalopathy (BSE) may have been passed to humans (Hu), resulting in a new form of Creutzfeldt–Jakob disease (CJD). We report here the transmission of bovine (Bo) prions to transgenic (Tg) mice expressing BoPrP; one Tg line exhibited incubation times of ?200 days. Like most cattle with BSE, vacuolation and astrocytic gliosis were confined in the brainstems of these Tg mice. Unexpectedly, mice expressing a chimeric Bo/Mo PrP transgene were resistant to BSE prions whereas mice expressing Hu or Hu/Mo PrP transgenes were susceptible to Hu prions. A comparison of differences in Mo, Bo, and Hu residues within the C terminus of PrP defines an epitope that modulates conversion of PrPC into PrPSc and, as such, controls prion transmission across species. Development of susceptible Tg(BoPrP) mice provides a means of measuring bovine prions that may prove critical in minimizing future human exposure.

Scott, Michael R.; Safar, Jiri; Telling, Glenn; Nguyen, Oanh; Groth, Darlene; Torchia, Marilyn; Koehler, Ruth; Tremblay, Patrick; Walther, Dirk; Cohen, Fred E.; DeArmond, Stephen J.; Prusiner, Stanley B.

1997-01-01

193

Prion Links  

NSDL National Science Digital Library

Prion Links, provided by Eiso AB of the Department of Biochemistry at the University of Groningen (Netherlands), contains 39 diverse links related to prion diseases and research. Although prion research has been going on for over 25 years, the scientific and medical communities have only recently acknowledged the existence of prions and there remains serious debate over their role in a variety of neurological diseases. The name "prion" is derived from "proteinaceous infectious particles," and was coined by Dr. Stanley Prusiner, who discovered the agents and who recently received the Nobel Prize for Medicine for his work. Prions are thought to be the first transmissible and heritable disease-causing agents that lack DNA and RNA. They are composed solely of protein and appear to be the cause of such diseases as kuru and Creutzfeldt-Jakob disease in humans, and bovine spongiform encephalopathies, mad cow disease, and scrapie in sheep and goats.

Ab, Eiso.

1996-01-01

194

Characterization of conformation-dependent prion protein epitopes.  

PubMed

Whereas prion replication involves structural rearrangement of cellular prion protein (PrP(C)), the existence of conformational epitopes remains speculative and controversial, and PrP transformation is monitored by immunoblot detection of PrP(27-30), a protease-resistant counterpart of the pathogenic scrapie form (PrP(Sc)) of PrP. We now describe the involvement of specific amino acids in conformational determinants of novel monoclonal antibodies (mAbs) raised against randomly chimeric PrP. Epitope recognition of two mAbs depended on polymorphisms controlling disease susceptibility. Detection by one, referred to as PRC5, required alanine and asparagine at discontinuous mouse PrP residues 132 and 158, which acquire proximity when residues 126-218 form a structured globular domain. The discontinuous epitope of glycosylation-dependent mAb PRC7 also mapped within this domain at residues 154 and 185. In accordance with their conformational dependence, tertiary structure perturbations compromised recognition by PRC5, PRC7, as well as previously characterized mAbs whose epitopes also reside in the globular domain, whereas conformation-independent epitopes proximal or distal to this region were refractory to such destabilizing treatments. Our studies also address the paradox of how conformational epitopes remain functional following denaturing treatments and indicate that cellular PrP and PrP(27-30) both renature to a common structure that reconstitutes the globular domain. PMID:22948149

Kang, Hae-Eun; Weng, Chu Chun; Saijo, Eri; Saylor, Vicki; Bian, Jifeng; Kim, Sehun; Ramos, Laylaa; Angers, Rachel; Langenfeld, Katie; Khaychuk, Vadim; Calvi, Carla; Bartz, Jason; Hunter, Nora; Telling, Glenn C

2012-09-04

195

Characterization of Conformation-dependent Prion Protein Epitopes*  

PubMed Central

Whereas prion replication involves structural rearrangement of cellular prion protein (PrPC), the existence of conformational epitopes remains speculative and controversial, and PrP transformation is monitored by immunoblot detection of PrP(27–30), a protease-resistant counterpart of the pathogenic scrapie form (PrPSc) of PrP. We now describe the involvement of specific amino acids in conformational determinants of novel monoclonal antibodies (mAbs) raised against randomly chimeric PrP. Epitope recognition of two mAbs depended on polymorphisms controlling disease susceptibility. Detection by one, referred to as PRC5, required alanine and asparagine at discontinuous mouse PrP residues 132 and 158, which acquire proximity when residues 126–218 form a structured globular domain. The discontinuous epitope of glycosylation-dependent mAb PRC7 also mapped within this domain at residues 154 and 185. In accordance with their conformational dependence, tertiary structure perturbations compromised recognition by PRC5, PRC7, as well as previously characterized mAbs whose epitopes also reside in the globular domain, whereas conformation-independent epitopes proximal or distal to this region were refractory to such destabilizing treatments. Our studies also address the paradox of how conformational epitopes remain functional following denaturing treatments and indicate that cellular PrP and PrP(27–30) both renature to a common structure that reconstitutes the globular domain.

Kang, Hae-Eun; Weng, Chu Chun; Saijo, Eri; Saylor, Vicki; Bian, Jifeng; Kim, Sehun; Ramos, Laylaa; Angers, Rachel; Langenfeld, Katie; Khaychuk, Vadim; Calvi, Carla; Bartz, Jason; Hunter, Nora; Telling, Glenn C.

2012-01-01

196

Linkage of prion protein and scrapie incubation time genes.  

PubMed

A single gene (Prn-i) that affects scrapie incubation period in mice has been identified. I/LnJ mice have a very long incubation period after inoculation of scrapie prions (200-385 days) and NZW/LacJ mice have a short one (113 +/- 2.8 days). (NZW X I/Ln)F1 hybrid mice had incubation times of 223 +/- 2.8 days indicating longer incubation times were dominant. Incubation periods in the backcross progeny of (NZW/LacJ X I/LnJ)F1 X NZW/LacJ segregated into two groups (64 mice, 130 +/- 1.1 d; 66 mice, 195 +/- 1.9 d) indicating single gene control. NZW/LacJ and 20 other inbred strains have the Prn-pa allele which is identified as a 3.8 kb Xbal fragment using a hamster PrP (prion protein) cDNA probe. I/LnJ and three other Prn-pb mouse strains have a 5.5 kb Xbal restriction fragment. Analysis of DNA from 66 backcross mice indicated Prn-i is tightly linked to Prn-p, the structural gene for PrP. PMID:3015416

Carlson, G A; Kingsbury, D T; Goodman, P A; Coleman, S; Marshall, S T; DeArmond, S; Westaway, D; Prusiner, S B

1986-08-15

197

Transport of the Pathogenic Prion Protein through Landfill Materials  

PubMed Central

Transmissible spongiform encephalopathies (TSEs, prion diseases) are a class of fatal neurodegenerative diseases affecting a variety of mammalian species including humans. A misfolded form of the prion protein (PrPTSE) is the major, if not sole, component of the infectious agent. Recent TSE outbreaks in domesticated and wild animal populations has created the need for safe and effective disposal of large quantities of potentially infected materials. Here, we report the results of a study to evaluate the potential for transport of PrPTSE derived from carcasses and associated wastes in a municipal solid waste (MSW) landfill. Column experiments were conducted to evaluate PrPTSE transport in quartz sand, two fine-textured burial soils currently used in landfill practice, a green waste residual material (a potential burial material), and fresh and aged MSW. PrPTSE was retained by quartz sand and the fine-textured burial soils, with no detectable PrPTSE eluted over more than 40 pore volumes. In contrast, PrPTSE was more mobile in MSW and green waste residual. Transport parameters were estimated from the experimental data and used to model PrPTSE migration in a MSW landfill. To the extent that the PrPTSE used mimics that released from decomposing carcasses, burial of CWD-infected materials at MSW landfills could provide secure containment of PrPTSE provided reasonable burial strategies (e.g., encasement in soil) are used.

Jacobson, Kurt H.; Lee, Seunghak; McKenzie, Debbie; Benson, Craig H.; Pedersen, Joel A.

2009-01-01

198

Glycan chains modulate prion protein binding to immobilized metal ions.  

PubMed

PrP(c) is the normal isoform of the prion protein which can be converted into PrP(Sc), the pathology-associated conformer in prion diseases. It contains two N-linked glycan chains attached to the C-proximal globular domain. While the biological functions of PrP(c) are still unknown, its ability to bind Cu(2+) is well documented. The main Cu(2+)-binding sites are located in the N-proximal, unstructured region of the molecule. Here we report that PrP(c) glycans influence the capacity of PrP(c) from sheep brain or cultured Rov cells to bind IMAC columns loaded with Cu(2+) or Co(2+). Using different anti-PrP antibodies and PrP(c) glycosylation mutants, we show that the full length non-glycosylated form of PrP(c) has a higher binding efficiency for column-bound Cu(2+) and Co(2+) than the corresponding glycosylated form. Our findings raise the possibility that the accessibility of the PrP(c) metal ion-binding sites might be controlled by the glycan chains. PMID:17293006

Moudjou, Mohammed; Bernard, Julie; Sabuncu, Elifsu; Langevin, Christelle; Laude, Hubert

2007-01-14

199

Cooperative binding modes of Cu(II) in prion protein  

NASA Astrophysics Data System (ADS)

The misfolding of the prion protein, PrP, is responsible for a group of neurodegenerative diseases including mad cow disease and Creutzfeldt-Jakob disease. It is known that the PrP can efficiently bind copper ions; four high-affinity binding sites located in the octarepeat region of PrP are now well known. Recent experiments suggest that at low copper concentrations new binding modes, in which one copper ion is shared between two or more binding sites, are possible. Using our hybrid Thomas-Fermi/DFT computational scheme, which is well suited for simulations of biomolecules in solution, we investigate the geometries and energetics of two, three and four binding sites cooperatively binding one copper ion. These geometries are then used as inputs for classical molecular dynamics simulations. We find that copper binding affects the secondary structure of the PrP and that it stabilizes the unstructured (unfolded) part of the protein.

Hodak, Miroslav; Chisnell, Robin; Lu, Wenchang; Bernholc, Jerry

2007-03-01

200

Copper-induced structural changes in the ovine prion protein are influenced by a polymorphism at codon 112  

Microsoft Academic Search

Prion diseases are associated with conformational change in the copper-binding protein PrP. The copper-binding sites in PrP are located in the N-terminal region of the molecule and comprise a series of tandem repeats of the sequence PHGGGWGQ together with two histidines at residues 96 and 111 (human PrP numbering). The co-ordination of copper ions within the non-octapeptide repeat metal ion-binding

Sujeong Yang; Alana M. Thackray; Tim J. Fitzmaurice; Raymond Bujdoso

2008-01-01

201

Ser170 controls the conformational multiplicity of the loop 166 175 in prion proteins: implication for conversion and species barrier  

Microsoft Academic Search

The self-perpetuating conversion of cel- lular prion proteins (PrPC) into an aggregated -sheet rich conformation is associated with transmissible spon- giform encephalopathies (TSE). The loop 166 -175 (L1) in PrPC, which displays sequence and structural variation among species, has been suggested to play a role in species barrier, in particular against transmis- sion of TSE from cervids to domestic and

Alemayehu A. Gorfe; Amedeo Caflisch

2007-01-01

202

Opposing effects of glutamine and asparagine govern prion formation by intrinsically disordered proteins  

PubMed Central

SUMMARY Sequences rich in glutamine (Q) and asparagine (N) residues often fail to fold at the monomer level. This, coupled to their unusual hydrogen-bonding abilities, provides the driving force to switch between disordered monomers and amyloids. Such transitions govern processes as diverse as human protein-folding diseases, bacterial biofilm assembly, and the inheritance of yeast prions (protein-based genetic elements). A systematic survey of prion-forming domains suggested that Q and N residues have distinct effects on amyloid formation. Here we use cell biological, biochemical, and computational techniques to compare Q/N-rich protein variants, replacing Ns with Qs and Qs with Ns. We find that the two residues have strong and opposing effects: N-richness promotes assembly of benign self-templating amyloids; Q-richness promotes formation of toxic non-amyloid conformers. Molecular simulations focusing on intrinsic folding differences between Qs and Ns suggest that their different behaviors are due to the enhanced turn-forming propensity of Ns over Qs.

Halfmann, Randal; Alberti, Simon; Krishnan, Rajaraman; Lyle, Nicholas; O'Donnell, Charles W.; King, Oliver D.; Berger, Bonnie; Pappu, Rohit V.; Lindquist, Susan

2011-01-01

203

Prion Protein Expression and Functional Importance in Skeletal Muscle  

PubMed Central

Abstract Skeletal muscle expresses prion protein (PrP) that buffers oxidant activity in neurons. Aims We hypothesize that PrP deficiency would increase oxidant activity in skeletal muscle and alter redox-sensitive functions, including contraction and glucose uptake. We used real-time polymerase chain reaction and Western blot analysis to measure PrP mRNA and protein in human diaphragm, five murine muscles, and muscle-derived C2C12 cells. Effects of PrP deficiency were tested by comparing PrP-deficient mice versus wild-type mice and morpholino-knockdown versus vehicle-treated myotubes. Oxidant activity (dichlorofluorescin oxidation) and specific force were measured in murine diaphragm fiber bundles. Results PrP content differs among mouse muscles (gastrocnemius>extensor digitorum longus, EDL>tibialis anterior, TA; soleus>diaphragm) as does glycosylation (di-, mono-, nonglycosylated; gastrocnemius, EDL, TA=60%, 30%, 10%; soleus, 30%, 40%, 30%; diaphragm, 30%, 30%, 40%). PrP is predominantly di-glycosylated in human diaphragm. PrP deficiency decreases body weight (15%) and EDL mass (9%); increases cytosolic oxidant activity (fiber bundles, 36%; C2C12 myotubes, 7%); and depresses specific force (12%) in adult (8–12?mos) but not adolescent (2?mos) mice. Innovation This study is the first to directly assess a role of prion protein in skeletal muscle function. Conclusions PrP content varies among murine skeletal muscles and is essential for maintaining normal redox homeostasis, muscle size, and contractile function in adult animals. Antioxid. Redox Signal. 15, 2465—2475.

Smith, Jeffrey D.; Moylan, Jennifer S.; Hardin, Brian J.; Chambers, Melissa A.; Estus, Steven; Telling, Glenn C.

2011-01-01

204

Transmissibility of Atypical Scrapie in Ovine Transgenic Mice: Major Effects of Host Prion Protein Expression and Donor Prion Genotype  

Microsoft Academic Search

Atypical scrapie or Nor98 has been identified as a transmissible spongiform encephalopathy (TSE) that is clearly distinguishable from classical scrapie and BSE, notably regarding the biochemical features of the protease-resistant prion protein PrPres and the genetic factors involved in susceptibility to the disease. In this study we transmitted the disease from a series of 12 French atypical scrapie isolates in

Jean-Noël Arsac; Dominique Bétemps; Eric Morignat; Cécile Féraudet; Anna Bencsik; Denise Aubert; Jacques Grassi; Thierry Baron

2009-01-01

205

Infectivity of scrapie prion protein (PrPSc) following in vitro digestion with bovine gastrointestinal microbiota.  

PubMed

The influence of a complex microflora residing in the gastrointestinal tract of cattle on the prion protein plays a crucial role with respect to early pathogenesis and the potential infectivity of faeces resulting in contamination of the environment. It is unknown whether infectious prion proteins, considered to be very stable, are inactivated by microbial processes in the gastrointestinal tract of animals during digestion. In our previous study it was shown that the scrapie-associated prion protein was degraded by ruminal and colonic microbiota of cattle, as indicated by a loss of anti-prion antibody 3F4 immunoreactivity in Western blot. Subsequently, in this study hamster bioassays with the pre-treated samples were performed. Although the PrP(Sc) signal was reduced up to immunochemically undetectable levels within 40 h of pre-treatment, significant residual prion infectivity was retained after degradation of infected hamster brain through the gastrointestinal microflora of cattle. The data presented here show that the loss of anti-prion antibody 3F4 immunoreactivity is obviously not correlated with a biological inactivation of PrP(Sc). These results highlight the deficiency of using Western blot in transmissible spongiform encephalopathies inactivation assessment studies and, additionally, point to the possibility of environmental contamination with faeces containing PrP(Sc) following an oral ingestion of prions. PMID:17542960

Scherbel, C; Pichner, R; Groschup, M H; Mueller-Hellwig, S; Scherer, S; Dietrich, R; Maertlbauer, E; Gareis, M

2007-01-01

206

Mouse Prion Protein (PrP) Segment 100 to 104 Regulates Conversion of PrPC to PrPSc in Prion-Infected Neuroblastoma Cells  

PubMed Central

Prion diseases are characterized by the replicative propagation of disease-associated forms of prion protein (PrPSc; PrP refers to prion protein). The propagation is believed to proceed via two steps; the initial binding of the normal form of PrP (PrPC) to PrPSc and the subsequent conversion of PrPC to PrPSc. We have explored the two-step model in prion-infected mouse neuroblastoma (ScN2a) cells by focusing on the mouse PrP (MoPrP) segment 92-GGTHNQWNKPSKPKTN-107, which is within a region previously suggested to be part of the binding interface or shown to differ in its accessibility to anti-PrP antibodies between PrPC and PrPSc. Exchanging the MoPrP segment with the corresponding chicken PrP segment (106-GGSYHNQKPWKPPKTN-121) revealed the necessity of MoPrP residues 99 to 104 for the chimeras to achieve the PrPSc state, while segment 95 to 98 was replaceable with the chicken sequence. An alanine substitution at position 100, 102, 103, or 104 of MoPrP gave rise to nonconvertible mutants that associated with MoPrPSc and interfered with the conversion of endogenous MoPrPC. The interference was not evoked by a chimera (designated MCM2) in which MoPrP segment 95 to 104 was changed to the chicken sequence, though MCM2 associated with MoPrPSc. Incubation of the cells with a synthetic peptide composed of MoPrP residues 93 to 107 or alanine-substituted cognates did not inhibit the conversion, whereas an anti-P8 antibody recognizing the above sequence in PrPC reduced the accumulation of PrPSc after 10 days of incubation of the cells. These results suggest the segment 100 to 104 of MoPrPC plays a key role in conversion after binding to MoPrPSc.

Hara, Hideyuki; Okemoto-Nakamura, Yuko; Shinkai-Ouchi, Fumiko; Hanada, Kentaro; Yamakawa, Yoshio

2012-01-01

207

Crystallographic Studies of Prion Protein (PrP) Segments Suggest How Structural Changes Encoded by Polymorphism at Residue 129 Modulate Susceptibility to Human Prion Disease*  

PubMed Central

A single nucleotide polymorphism (SNP) in codon 129 of the human prion gene, leading to a change from methionine to valine at residue 129 of prion protein (PrP), has been shown to be a determinant in the susceptibility to prion disease. However, the molecular basis of this effect remains unexplained. In the current study, we determined crystal structures of prion segments having either Met or Val at residue 129. These 6-residue segments of PrP centered on residue 129 are “steric zippers,” pairs of interacting ?-sheets. Both structures of these “homozygous steric zippers” reveal direct intermolecular interactions between Met or Val in one sheet and the identical residue in the mating sheet. These two structures, plus a structure-based model of the heterozygous Met-Val steric zipper, suggest an explanation for the previously observed effects of this locus on prion disease susceptibility and progression.

Apostol, Marcin I.; Sawaya, Michael R.; Cascio, Duilio; Eisenberg, David

2010-01-01

208

Crystallographic Studies of Prion Protein (PrP) Segments Suggest How Structural Changes Encoded by Polymorphism at Residue 129 Modulate Susceptibility to Human Prion Disease  

SciTech Connect

A single nucleotide polymorphism (SNP) in codon 129 of the human prion gene, leading to a change from methionine to valine at residue 129 of prion protein (PrP), has been shown to be a determinant in the susceptibility to prion disease. However, the molecular basis of this effect remains unexplained. In the current study, we determined crystal structures of prion segments having either Met or Val at residue 129. These 6-residue segments of PrP centered on residue 129 are 'steric zippers,' pairs of interacting {beta}-sheets. Both structures of these 'homozygous steric zippers' reveal direct intermolecular interactions between Met or Val in one sheet and the identical residue in the mating sheet. These two structures, plus a structure-based model of the heterozygous Met-Val steric zipper, suggest an explanation for the previously observed effects of this locus on prion disease susceptibility and progression.

Apostol, Marcin I.; Sawaya, Michael R.; Cascio, Duilio; Eisenberg, David (UCLA)

2010-09-23

209

Prion protein as a target for therapeutic interventions  

Microsoft Academic Search

Transmissible spongiform encephalopathies (TSEs), currently known as prion diseases, are neurodegenerative disorders of the central nervous system (CNS) caused by an elusive infectious agent called \\

Pawel P. Liberski

2004-01-01

210

The unfolded state of the murine prion protein and properties of single-point mutants related to human prion diseases.  

PubMed

The prion protein can exist both in a normal cellular isoform and in a pathogenic conformational isoform. The latter is responsible for the development of different neurodegenerative diseases, for example Creutzfeldt-Jakob disease or fatal familial insomnia. To convert the native benign state of the protein into a highly ordered fibrillar aggregate, large-scale rearrangements of the tertiary structure are necessary during the conversion process and intermediates that are at least partially unfolded are present during fibril formation. In addition to the sporadic conversion into the pathogenic isoform, more than 20 familial diseases are known that are caused by single point mutations increasing the probability of aggregation and neurodegeneration. Here, we demonstrate that the chemically denatured states of the mouse and human prion proteins have very similar structural and dynamic characteristics. Initial studies on the single point mutants E196K, F198S, V203I and R208H of the oxidized mouse construct, which are related to human prion diseases, reveal significant differences in the rate of aggregation. Aggregation for mutants V203I and R208H is slower than it is for the wild type, and the constructs E196K and F198S show accelerated aggregation. These differences in aggregation behaviour are not correlated with the thermal stability of the mutants, indicating different mechanisms promoting the conformational conversion process. PMID:20541558

Gerum, Christian; Schlepckow, Kai; Schwalbe, Harald

2010-06-10

211

Three hamster species with different scrapie incubation times and neuropathological features encode distinct prion proteins.  

PubMed Central

Given the critical role of the prion protein (PrP) in the transmission and pathogenesis of experimental scrapie, we investigated the PrP gene and its protein products in three hamster species, Chinese (CHa), Armenian (AHa), and Syrian (SHa), each of which were found to have distinctive scrapie incubation times. Passaging studies demonstrated that the host species, and not the source of scrapie prions, determined the incubation time for each species, and histochemical studies of hamsters with clinical signs of scrapie revealed characteristic patterns of neuropathology. Northern (RNA) analysis showed the size of PrP mRNA from CHa, AHa, and SHa hamsters to be 2.5, 2.4, and 2.1 kilobases, respectively. Immunoblotting demonstrated that the PrP isoforms were of similar size (33 to 35 kilodaltons); however, the monoclonal antibody 13A5 raised against SHa PrP did not react with the CHa or AHa PrP molecules. Comparison of the three predicted amino acid sequences revealed that each is distinct. Furthermore, differences within the PrP open reading frame that uniquely distinguish the three hamster species are within a hydrophilic segment of 11 amino acids that includes polymorphisms linked to scrapie incubation times in inbred mice and an inherited prion disease of humans. Single polymorphisms in this region correlate with the presence or absence of amyloid plaques for a given hamster species or mouse inbred strain. Our findings demonstrate distinctive molecular, pathological, and clinical characteristics of scrapie in three related species and are consistent with the hypothesis that molecular properties of the host PrP play a pivotal role in determining the incubation time and neuropathological features of scrapie. Images

Lowenstein, D H; Butler, D A; Westaway, D; McKinley, M P; DeArmond, S J; Prusiner, S B

1990-01-01

212

Copper and prion disease  

Microsoft Academic Search

The prion protein is a cell surface glyco-protein expressed by neurones. Its function has remained elusive until it was recently shown to be a copper binding protein. There is now strong evidence that the prion protein has a role in normal brain copper metabolism. Prion protein expression alters copper uptake into cells and enhances copper incorporation into superoxide dismutase. Furthermore

David R Brown

2001-01-01

213

Capillary electromigration based techniques in diagnostics of prion protein caused diseases.  

PubMed

Transmissible spongiform encephalopathies are a group of fatal neurodegenerative diseases with long incubation time. This group includes Creutzfeld-Jakob disease, kuru, scrapie, chronic wasting disease, and bovine spongiform encephalopathy. Sensitive and specific detection of abnormal prion protein as "a source agent" of the above-mentioned diseases in blood could provide a diagnostic test or a screening assay for animal and human prion protein diseases diagnostics. Therefore, diagnostic tests for prion protein diseases represent unique challenge requiring development of novel assays exploiting properties of prion protein complex. Presently, diagnostic methods such as protein misfolding cyclic amplification, conformation-dependent immunoassay, dissociation-enhanced lanthanide fluorescent immunoassay, fluorescence correlation spectroscopy, and/or flow microbead immunoassay are used for abnormal prion protein (PrP(Sc) ) detection. On the other hand, using of CE for PrP(Sc) detection in body fluids is an attractive alternative; it has been already applied for the blood samples of infected sheep, elk, chimpanzee, as well as humans. In this review, assays for prion protein detection are summarized with special attention to capillary electromigration based techniques, such as CE, CIEF, and/or CGE. The potential of the miniaturized and integrated lab-on-chip devices is highlighted, emphasizing recent advances of this field in the proteomic analysis. PMID:23161211

Sobrova, Pavlina; Ryvolova, Marketa; Adam, Vojtech; Kizek, Rene

2012-12-04

214

?-amyloid oligomers and cellular prion protein in Alzheimer's disease  

PubMed Central

Prefibrillar oligomers of the ?-amyloid peptide (A?) are recognized as potential mediators of Alzheimer's disease (AD) pathophysiology. Deficits in synaptic function, neurotoxicity, and the progression of AD have all been linked to the oligomeric A? assemblies rather than to A? monomers or to amyloid plaques. However, the molecular sites of A? oligomer action have remained largely unknown. Recently, the cellular prion protein (PrPC) has been shown to act as a functional receptor for A? oligomers in brain slices. Because PrPC serves as the substrate for Creutzfeldt–Jakob Disease (CJD), these data suggest mechanistic similarities between the two neurodegenerative diseases. Here, we review the importance of A? oligomers in AD, commonalities between AD and CJD, and the newly emergent role of PrPC as a receptor for A? oligomers.

Gunther, Erik C.; Strittmatter, Stephen M.

2010-01-01

215

Aggregation & Localization of a Disease-Associated Prion Protein (PrP) Mutant  

Microsoft Academic Search

OF THE DISSERTATION Aggregation & Localization of a Disease-Associated Prion Protein (PrP) Mutant by Andrea Rhonda Zaragoza Medrano Doctor of Philosophy in Biology and Biomedical Sciences (Genetics) Washington University in St. Louis, 2009 Professor David A. Harris, Chairperson Prion protein (PrP) is a GPI-anchored sialoglycoprotein involved in the pathogenesis of infectious and inherited forms of transmissible spongiform encephalopathies (TSEs). A

Andrea Rhonda Medrano

2009-01-01

216

Cell-surface prion protein interacts with glycosaminoglycans.  

PubMed Central

We used ELISA and flow cytometry to study the binding of prion protein PrP to glycosaminoglycans (GAGs). We found that recombinant human PrP (rPrP) binds GAGs including chondroitin sulphate A, chondroitin sulphate B, hyaluronic acid, and heparin. rPrP binding to GAGs occurs via the N-terminus, a region known to bind divalent cations. Additionally, rPrP binding to GAGs is enhanced in the presence of Cu2+ and Zn2+, but not Ca2+ and Mn2+. rPrP binds heparin strongest, and the binding is inhibited by certain heparin analogues, including heparin disaccharide and sulphate-containing monosaccharides, but not by acetylated heparin. Full-length normal cellular prion protein (PrPC), but not N-terminally truncated PrPC species, from human brain bind GAGs in a similar Cu2+/Zn2+-enhanced fashion. We found that GAGs specifically bind to a synthetic peptide corresponding to amino acid residues 23-35 in the N-terminus of rPrP. We further demonstrated that while both wild-type PrPC and an octapeptide-repeat-deleted mutant PrP produced by transfected cells bound heparin at the cell surface, the PrP N-terminal deletion mutant and non-transfectant control failed to bind heparin. Binding of heparin to wild-type PrPC on the cell surface results in a reduction of the level of cell-surface PrPC. These results provide strong evidence that PrPC is a surface receptor for GAGs.

Pan, Tao; Wong, Boon-Seng; Liu, Tong; Li, Ruliang; Petersen, Robert B; Sy, Man-Sun

2002-01-01

217

Prion Protein Expression Regulates Embryonic Stem Cell Pluripotency and Differentiation  

PubMed Central

Cellular prion protein (PRNP) is a glycoprotein involved in the pathogenesis of transmissible spongiform encephalopathies (TSEs). Although the physiological function of PRNP is largely unknown, its key role in prion infection has been extensively documented. This study examines the functionality of PRNP during the course of embryoid body (EB) differentiation in mouse Prnp-null (KO) and WT embryonic stem cell (ESC) lines. The first feature observed was a new population of EBs that only appeared in the KO line after 5 days of differentiation. These EBs were characterized by their expression of several primordial germ cell (PGC) markers until Day 13. In a comparative mRNA expression analysis of genes playing an important developmental role during ESC differentiation to EBs, Prnp was found to participate in the transcription of a key pluripotency marker such as Nanog. A clear switching off of this gene on Day 5 was observed in the KO line as opposed to the WT line, in which maximum Prnp and Nanog mRNA levels appeared at this time. Using a specific antibody against PRNP to block PRNP pathways, reduced Nanog expression was confirmed in the WT line. In addition, antibody-mediated inhibition of ITGB5 (integrin ?v?5) in the KO line rescued the low expression of Nanog on Day 5, suggesting the regulation of Nanog transcription by Prnp via this Itgb5. mRNA expression analysis of the PRNP-related proteins PRND (Doppel) and SPRN (Shadoo), whose PRNP function is known to be redundant, revealed their incapacity to compensate for the absence of PRNP during early ESC differentiation. Our findings provide strong evidence for a relationship between Prnp and several key pluripotency genes and attribute Prnp a crucial role in regulating self-renewal/differentiation status of ESC, confirming the participation of PRNP during early embryogenesis.

Miranda, Alberto; Pericuesta, Eva

2011-01-01

218

Prion protein detection in serum using micromechanical resonator arrays.  

PubMed

Prion proteins that have transformed from their normal cellular counterparts (PrP(c)) into infectious form (PrP(res)) are responsible for causing progressive neurodegenerative diseases in numerous species, such as bovine spongiform encephalopathy (BSE) in cattle (also known as mad cow disease), scrapie in sheep, and Creutzfeldt-Jakob disease (CJD) in humans. Due to a possible link between BSE and CJD it is highly desirable to develop non-invasive and ante mortem tests for the detection of prion proteins in bovine samples. Such ante mortem tests of all cows prior to slaughter will help to prevent the introduction of PrP(res) into the human food supply. Furthermore, detection of PrP(res) in donated blood will also help to prevent the transmission of CJD among humans through blood transfusion. In this study, we have continued development of a micromechanical resonator array that is capable of detecting PrP(c) in bovine blood serum. The sensitivity of the resonators for the detection of PrP(c) is further enhanced by the use of secondary mass labels. A pair of antibodies is used in a sandwich immunoassay format to immobilize PrP(c) on the surface of resonators and attach nanoparticles as secondary mass labels to PrP(c). Secondary mass labeling is optimized in terms of incubation time to maximize the frequency shifts that correspond to the presence of PrP(c) on the surface of resonators. Our results show that a minimum of 200 pg mL(-1) of PrP(c) in blood serum can be detected using micromechanical resonator arrays. PMID:19836525

Varshney, Madhukar; Waggoner, Philip S; Montagna, Richard A; Craighead, Harold G

2009-07-23

219

Chimeric elk/mouse prion proteins in transgenic mice.  

PubMed

Chronic wasting disease (CWD) of deer and elk is a highly communicable neurodegenerative disorder caused by prions. Investigations of CWD are hampered by slow bioassays in transgenic (Tg) mice. Towards the development of Tg mice that will be more susceptible to CWD prions, we created a series of chimeric elk/mouse transgenes that encode the N terminus of elk PrP (ElkPrP) up to residue Y168 and the C terminus of mouse PrP (MoPrP) beyond residue 169 (mouse numbering), designated Elk3M(SNIVVK). Between codons 169 and 219, six residues distinguish ElkPrP from MoPrP: N169S, T173N, V183I, I202V, I214V and R219K. Using chimeric elk/mouse PrP constructs, we generated 12 Tg mouse lines and determined incubation times after intracerebral inoculation with the mouse-passaged RML scrapie or Elk1P CWD prions. Unexpectedly, one Tg mouse line expressing Elk3M(SNIVVK) exhibited incubation times of <70 days when inoculated with RML prions; a second line had incubation times of <90 days. In contrast, mice expressing full-length ElkPrP had incubation periods of >250 days for RML prions. Tg(Elk3M,SNIVVK) mice were less susceptible to CWD prions than Tg(ElkPrP) mice. Changing three C-terminal mouse residues (202, 214 and 219) to those of elk doubled the incubation time for mouse RML prions and rendered the mice resistant to Elk1P CWD prions. Mutating an additional two residues from mouse to elk at codons 169 and 173 increased the incubation times for mouse prions to >300 days, but made the mice susceptible to CWD prions. Our findings highlight the role of C-terminal residues in PrP that control the susceptibility and replication of prions. PMID:23100369

Tamgüney, Gültekin; Giles, Kurt; Oehler, Abby; Johnson, Natrina L; DeArmond, Stephen J; Prusiner, Stanley B

2012-10-24

220

Balancing selection at the prion protein gene consistent with prehistoric kurulike epidemics.  

PubMed

Kuru is an acquired prion disease largely restricted to the Fore linguistic group of the Papua New Guinea Highlands, which was transmitted during endocannibalistic feasts. Heterozygosity for a common polymorphism in the human prion protein gene (PRNP) confers relative resistance to prion diseases. Elderly survivors of the kuru epidemic, who had multiple exposures at mortuary feasts, are, in marked contrast to younger unexposed Fore, predominantly PRNP 129 heterozygotes. Kuru imposed strong balancing selection on the Fore, essentially eliminating PRNP 129 homozygotes. Worldwide PRNP haplotype diversity and coding allele frequencies suggest that strong balancing selection at this locus occurred during the evolution of modern humans. PMID:12690204

Mead, Simon; Stumpf, Michael P H; Whitfield, Jerome; Beck, Jonathan A; Poulter, Mark; Campbell, Tracy; Uphill, James B; Goldstein, David; Alpers, Michael; Fisher, Elizabeth M C; Collinge, John

2003-04-10

221

Co-existence of scrapie prion protein types 1 and 2 in sporadic Creutzfeldt-Jakob disease: its effect on the phenotype and prion-type characteristics  

Microsoft Academic Search

Five phenotypically distinct subtypes have been identified in sporadic Creutzfeldt-Jakob disease (sCJD), based on the methionine\\/valine polymorphic genotype of codon 129 of the prion protein (PrP) gene and the presence of either one of the two protease K-resistant scrapie prion protein (PrPSc) types identified as 1 and 2. The infrequent co-existence of both PrPSc types in the same case has

I. Cali; R. Castellani; A. Alshekhlee; Y. Cohen; J. Blevins; J. Yuan; J. P. M. Langeveld; P. Parchi; J. G. Safar; W.-Q. Zou; P. Gambetti

2009-01-01

222

Inherited Creutzfeldt-Jakob disease in a British family associated with a novel 144 base pair insertion of the prion protein gene  

Microsoft Academic Search

A case of familial Creutzfeldt-Jakob disease associated with a 144 base pair insertion in the open reading frame of the prion protein gene is described. Sequencing of the mutated allele showed an arrangement of six octapeptide repeats, distinct from that of a recently described British family with an insertion of similar size. Thirteen years previously the brother of the proband

D Nicholl; O Windl; R de Silva; S Sawcer; M Dempster; J W Ironside; J P Estibeiro; G M Yuill; R Lathe; R G Will

1995-01-01

223

POLYMORPHIC DISTRIBUTION OF THE PRION PROTEIN (PRNP) GENE IN SCRAPIE-INFECTED SHEEP FLOCKS IN WHICH EMBRYO TRANSFER WAS USED TO CIRCUMVENT THE TRANSMISSIONS OF SCRAPIE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The genetic sequence of the ovine prion protein (PrP) gene between codons 102 and 175, with emphasis on ovine PrP gene codons 136 and 171, was determined in scrapie-exposed Suffolk embryo donors and in offspring from those donors that had been transferred to scrapie-free recipient ewes. The most com...

224

Shotgun protein sequencing.  

SciTech Connect

A novel experimental and computational technique based on multiple enzymatic digestion of a protein or protein mixture that reconstructs protein sequences from sequences of overlapping peptides is described in this SAND report. This approach, analogous to shotgun sequencing of DNA, is to be used to sequence alternative spliced proteins, to identify post-translational modifications, and to sequence genetically engineered proteins.

Faulon, Jean-Loup Michel; Heffelfinger, Grant S.

2009-06-01

225

Genetics of human prion disease.  

PubMed

Prion diseases are fatal neurodegenerative disorders in which an abnormal isoform of prion protein (PrPSc) accumulates in brain. Prion disease is either inherited as an autosomal dominant disorder with very high penetrance, sporadic, where no epidemiological association with other human or animal prion diseases can be demonstrated or acquired, where disease results from contamination with PrPSc from another case of prion disease. No human case of prion disease is known to have been acquired from an animal but about 50 cases have been acquired from contaminated growth hormone or gonadotrophin prepared from human pituitaries, from human meningeal transplants or other neuro-surgical procedures. Several thousand cases of the prion disease, kuru, occurred in Papua New Guinea, mainly during the first half of this century. This epidemic probably started with a sporadic case of Creutzfeldt-Jakob disease but was transmitted through funerary practices which are though to have involved endo-cannibalism. Inherited cases of prion disease are associated with mutations in the PrP gene. There are at least five point mutations and a further five mutations involving five to nine extra repeats of the five octapeptide repeat sequence in the PrP gene, all of which may lead to one of the forms of human prion disease i.e. Creutzfeldt-Jakob disease, Gerstmann-Sträussler syndrome and atypical prion dementia. In addition there is a common polymorphism at codon 129 of the PrP gene. This may affect age at onset and duration of illness in inherited and sporadic cases.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7903647

Ridley, R M; Baker, H F

1993-01-01

226

Distinctive cerebellar immunoreactivity for the prion protein in familial (E200K) Creutzfeldt-Jakob disease  

Microsoft Academic Search

We have compared the immunomorphological spectrum of the deposition of the disease-associated prion protein (PrPSc) in the cerebral and cerebellar cortex of 32 Creutzfeldt-Jakob disease (CJD) patients with the PrP gene (PRNP) E200K mutation to 45 sporadic CJD and 14 other genetic prion disease cases. PrP deposits correlate with the genotype at the methionine\\/valine (MV) polymorphic codon 129. While the

Christa Jarius; Gabor G. Kovacs; Girma Belay; Johannes A. Hainfellner; Eva Mitrova; Herbert Budka

2003-01-01

227

Prion protein self-interactions : a gateway to novel therapeutic strategies?  

Microsoft Academic Search

Transmissible Spongiform Encephalopathies (TSEs) or prion diseases are unique disorders that are not caused by infectious micro-organisms (bacteria or fungi), viruses or parasites, but rather seems to be the result of an infectious protein. TSEs are comprised of fatal neurodegenerative disorders affecting both human and animals. Prion diseases cause sponge-like degeneration of neuronal tissue and include (among others) Creutzfeldt-Jacob disease

A. Rigter

2011-01-01

228

Cellular prion protein protects against reactive-oxygen-species-induced DNA damage  

Microsoft Academic Search

Although the cellular form of the prion protein (PrPC) is critical for the development of prion disease through its conformational conversion into the infectious form (PrPSc), the physiological role of PrPC is less clear. Using alkaline single-cell gel electrophoresis (the Comet assay), we show that expression of PrPC protects human neuroblastoma SH-SY5Y cells against DNA damage under basal conditions and

Nicole T. Watt; Michael N. Routledge; Christopher P. Wild; Nigel M. Hooper

2007-01-01

229

Selective Processing and Metabolism of Disease-Causing Mutant Prion Proteins  

Microsoft Academic Search

Prion diseases are fatal neurodegenerative disorders caused by aberrant metabolism of the cellular prion protein (PrPC). In genetic forms of these diseases, mutations in the globular C-terminal domain are hypothesized to favor the spontaneous generation of misfolded PrP conformers (including the transmissible PrPSc form) that trigger downstream pathways leading to neuronal death. A mechanistic understanding of these diseases therefore requires

Aarthi Ashok; Ramanujan S. Hegde

2009-01-01

230

Prion channel proteins and their role in vacuolation and neurodegenerative diseases  

Microsoft Academic Search

The prion encephalopathies, which are characterized by neuropathological changes that include vacuolation, astrocytosis, the development of amyloid plaques and neuronal loss, are associated with the conversion of a normal cellular isoform of prion protein (PrPc) to an abnormal pathologic scrapie isoform (PrPSc). The use of PrP[106-126] and its isoforms in studies of channels in lipid bilayers has revealed that it

Joseph I. Kourie

2002-01-01

231

Preclinical Deposition of Pathological Prion Protein in Muscle of Experimentally Infected Primates  

Microsoft Academic Search

Prion diseases are transmissible fatal neurodegenerative disorders affecting humans and animals. A central step in disease progression is the accumulation of a misfolded form (PrPSc) of the host encoded prion protein (PrPC) in neuronal and non-neuronal tissues. The involvement of peripheral tissues in preclinical states increases the risk of accidental transmission. On the other hand, detection of PrPSc in non-neuronal

Susanne Krasemann; Melanie Neumann; Markus Geissen; Walter Bodemer; Franz-Josef Kaup; Walter Schulz-Schaeffer; Nathalie Morel; Adriano Aguzzi; Markus Glatzel; Per Westermark

2010-01-01

232

Glypican-1 Mediates Both Prion Protein Lipid Raft Association and Disease Isoform Formation  

Microsoft Academic Search

In prion diseases, the cellular form of the prion protein, PrPC, undergoes a conformational conversion to the infectious isoform, PrPSc. PrPC associates with lipid rafts through its glycosyl-phosphatidylinositol (GPI) anchor and a region in its N- terminal domain which also binds to heparan sulfate proteoglycans (HSPGs). We show that heparin displaces PrPC from rafts and promotes its endocytosis, suggesting that

David R. Taylor; Isobel J. Whitehouse; Nigel M. Hooper

2009-01-01

233

Detection of Bovine Spongiform Encephalopathy-Related Prion Protein Gene Promoter Polymorphisms in Local Turkish Cattle  

Microsoft Academic Search

Polymorphisms in open reading frames of the prion protein gene (PRNP) have been shown to be associated with prion disease susceptibility in humans, sheep, and mice. Studies in recent years have\\u000a demonstrated a similar effect of PRNP promoter and intron-1 polymorphisms on bovine spongiform encephalopathy (BSE) susceptibility in cattle. In this study, the\\u000a deletion\\/insertion (indel) polymorphisms of the bovine PRNP

Cemal Ün; Kemal Oztabak; Nehir Özdemir; Dawit Tesfaye; Ahmet Mengi; Karl Schellander

2008-01-01

234

Intraepithelial and Interstitial Deposition of Pathological Prion Protein in Kidneys of Scrapie-Affected Sheep  

Microsoft Academic Search

Prions have been documented in extra-neuronal and extra-lymphatic tissues of humans and various ruminants affected by Transmissible Spongiform Encephalopathy (TSE). The presence of prion infectivity detected in cervid and ovine blood tempted us to reason that kidney, the organ filtrating blood derived proteins, may accumulate disease associated PrPSc. We collected and screened kidneys of experimentally, naturally scrapie-affected and control sheep

Ciriaco Ligios; Giovanna Maria Cancedda; Ilan Margalith; Cinzia Santucciu; Laura Madau; Caterina Maestrale; Massimo Basagni; Mariangela Saba; Mathias Heikenwalder; Neil Mabbott

2007-01-01

235

Cloning and expression of prion protein encoding gene of flounder ( Paralichthys olivaceus)  

NASA Astrophysics Data System (ADS)

The prion protein (PrP) encoding gene of flounder ( Paralichthys olivaceus) was cloned. It was not interrupted by an intron. This gene has two promoters in its 5' upstream, indicating that its transcription may be intensive, and should have an important function. It was expressed in all 14 tissues tested, demonstrating that it is a house-keeping gene. Its expression in digestion and reproduction systems implies that the possible prions of fish may transfer horizontally.

Zhang, Zhiwen; Sun, Xiuqin; Zhang, Jinxing; Zan, Jindong

2008-02-01

236

Diagnosing prion diseases: needs, challenges and hopes  

Microsoft Academic Search

Prion diseases are among the most intriguing infectious diseases and are associated with unconventional proteinaceous infectious agents known as prions. Prions seem to lack nucleic acid and propagate by transmission of protein misfolding. The nature of prions and their unique mode of transmission present challenges for early diagnosis of prion diseases. In this article, state-of-the-art prion diagnostic techniques, together with

Claudio Soto

2004-01-01

237

Prion Diseases  

NSDL National Science Digital Library

Prion Diseases is one of a set of lecture notes for Virology 335 by Shaun Heaphy of Leicester University (UK). It contains detailed information on its topic, along with selected links. Although prion research has been going on for over 25 years, the scientific and medical communities have only recently acknowledged the existence of prions and there remains serious debate over their role in a variety of neurological diseases. The name "prion" is derived from "proteinaceous infectious particles," and was coined by Dr. Stanley Prusiner, who discovered the agents and who recently received the Nobel Prize for Medicine for his work. Prions are thought to be the first transmissible and heritable disease-causing agents that lack DNA and RNA. They are composed solely of protein and appear to be the cause of such diseases as kuru and Creutzfeldt-Jakob disease in humans, and bovine spongiform encephalopathies, mad cow disease, and scrapie in sheep and goats.

Heaphy, Shaun.

1997-01-01

238

N-terminal peptides from unprocessed prion proteins enter cells by macropinocytosis  

SciTech Connect

A peptide derived from the N-terminus of the unprocessed bovine prion protein (bPrPp), incorporating the hydrophobic signal sequence (residues 1-24) and a basic domain (KKRPKP, residues 25-30), internalizes into mammalian cells, even when coupled to a sizeable cargo, and therefore functions as a cell-penetrating peptide (CPP). Confocal microscopy and co-localization studies indicate that the internalization of bPrPp is mainly through macropinocytosis, a fluid-phase endocytosis process, initiated by binding to cell-surface proteoglycans. Electron microscopy studies show internalized bPrPp-DNA-gold complexes residing in endosomal vesicles. bPrPp induces expression of a complexed luciferase-encoding DNA plasmid, demonstrating the peptide's ability to transport the cargo across the endosomal membrane and into the cytosol and nucleus. The novel CPP activity of the unprocessed N-terminal domain of PrP could be important for the retrotranslocation of partly processed PrP and for PrP trafficking inside or between cells, with implications for the infectivity associated with prion diseases.

Magzoub, Mazin [Department of Biochemistry and Biophysics, Stockholm University (Sweden); Sandgren, Staffan [Department of Clinical Sciences, Section for Oncology, Lund University (Sweden); Lundberg, Pontus [Department of Neurochemistry, Stockholm University (Sweden); Oglecka, Kamila [Department of Biochemistry and Biophysics, Stockholm University (Sweden); Lilja, Johanna [Department of Clinical Sciences, Section for Oncology, Lund University (Sweden); Wittrup, Anders [Department of Clinical Sciences, Section for Oncology, Lund University (Sweden); Goeran Eriksson, L.E. [Department of Biochemistry and Biophysics, Stockholm University (Sweden); Langel, Ulo [Department of Neurochemistry, Stockholm University (Sweden); Belting, Mattias [Department of Clinical Sciences, Section for Oncology, Lund University (Sweden)]. E-mail: mattias.belting@med.lu.se; Graeslund, Astrid [Department of Biochemistry and Biophysics, Stockholm University (Sweden)]. E-mail: astrid@dbb.su.se

2006-09-22

239

Copper attachment to a non-octarepeat site in prion protein  

NASA Astrophysics Data System (ADS)

Prion protein, PrP, plays a causative role in several neurodegenerative diseases, including mad cow disease in cattle and Creutzfeldt-Jakob disease in humans. The PrP is known to efficiently bind copper ions and this ability has been linked to its function. PrP contains up to six binding sites, four of which are located in the so-called octarepeat region and are now well known. The binding sites outside this region are still largely undetermined, despite evidence of their relevance to prion diseases. Using a hybrid DFT/DFT, which combines Kohn-Sham DFT with orbital-free DFT to achieve accurate and efficient description of solvent effects in ab initio calculations, we have investigated copper attachment to the sequence GGGTH, which represents the copper binding site located at His96. We have considered both NNNN and NNNO types of copper coordination, as suggested by experiments. Our calculations have determined the geometry of copper attachment site and its energetics. Comparison to the already known binding sites provides insight into the process of copper uptake in PrP.

Hodak, Miroslav; Bernholc, Jerry

2010-03-01

240

Hsp70 targets Hsp100 chaperones to substrates for protein disaggregation and prion fragmentation.  

PubMed

Hsp100 and Hsp70 chaperones in bacteria, yeast, and plants cooperate to reactivate aggregated proteins. Disaggregation relies on Hsp70 function and on ATP-dependent threading of aggregated polypeptides through the pore of the Hsp100 AAA(+) hexamer. In yeast, both chaperones also promote propagation of prions by fibril fragmentation, but their functional interplay is controversial. Here, we demonstrate that Hsp70 chaperones were essential for species-specific targeting of their Hsp100 partner chaperones ClpB and Hsp104, respectively, to heat-induced protein aggregates in vivo. Hsp70 inactivation in yeast also abrogated Hsp104 targeting to almost all prions tested and reduced fibril mobility, which indicates that fibril fragmentation by Hsp104 requires Hsp70. The Sup35 prion was unique in allowing Hsp70-independent association of Hsp104 via its N-terminal domain, which, however, was nonproductive. Hsp104 overproduction even outcompeted Hsp70 for Sup35 prion binding, which explains why this condition prevented Sup35 fragmentation and caused prion curing. Our findings indicate a conserved mechanism of Hsp70-Hsp100 cooperation at the surface of protein aggregates and prion fibrils. PMID:22869599

Winkler, Juliane; Tyedmers, Jens; Bukau, Bernd; Mogk, Axel

2012-08-01

241

Origins and evolution of the HET-s prion-forming protein: searching for other amyloid-forming solenoids.  

PubMed

The HET-s prion-forming domain from the filamentous fungus Podospora anserina is gaining considerable interest since it yielded the first well-defined atomic structure of a functional amyloid fibril. This structure has been identified as a left-handed beta solenoid with a triangular hydrophobic core. To delineate the origins of the HET-s prion-forming protein and to discover other amyloid-forming proteins, we searched for all homologs of the HET-s protein in a database of protein domains and fungal genomes, using a combined application of HMM, psi-blast and pGenThreader techniques, and performed a comparative evolutionary analysis of the N-terminal alpha-helical domain and the C-terminal prion-forming domain of HET-s. By assessing the tandem evolution of both domains, we observed that the prion-forming domain is restricted to Sordariomycetes, with a marginal additional sequence homolog in Arthroderma otae as a likely case of horizontal transfer. This suggests innovation and rapid evolution of the solenoid fold in the Sordariomycetes clade. In contrast, the N-terminal domain evolves at a slower rate (in Sordariomycetes) and spans many diverse clades of fungi. We performed a full three-dimensional protein threading analysis on all identified HET-s homologs against the HET-s solenoid fold, and present detailed structural annotations for identified structural homologs to the prion-forming domain. An analysis of the physicochemical characteristics in our set of structural models indicates that the HET-s solenoid shape can be readily adopted in these homologs, but that they are all less optimized for fibril formation than the P. anserina HET-s sequence itself, due chiefly to the presence of fewer asparagine ladders and salt bridges. Our combined structural and evolutionary analysis suggests that the HET-s shape has "limited scope" for amyloidosis across the wider protein universe, compared to the 'generic' left-handed beta helix. We discuss the implications of our findings on future identification of amyloid-forming proteins sharing the solenoid fold. PMID:22096554

Gendoo, Deena M A; Harrison, Paul M

2011-11-11

242

Differential stability of the bovine prion protein upon urea unfolding  

PubMed Central

Prion diseases, or transmissible spongiform encephalopathies, are a group of infectious neurological diseases associated with the structural conversion of an endogenous protein (PrP) in the central nervous system. There are two major forms of this protein: the native and noninfectious cellular form, PrPC; and the misfolded, infectious, and proteinase K-resistant form, PrPSc. The C-terminal domain of PrPC is mainly ?-helical in structure, whereas PrPSc in known to aggregate into an assembly of ?-sheets, forming amyloid fibrils. To identify the regions of PrPC potentially involved in the initial steps of the conversion to the infectious conformation, we have used high-resolution NMR spectroscopy to characterize the stability and structure of bovine recombinant PrPC (residues 121 to 230) during unfolding with the denaturant urea. Analysis of the 800 MHz 1H NMR spectra reveals region-specific information about the structural changes occurring upon unfolding. Our data suggest that the dissociation of the native ?-sheet of PrPC is a primary step in the urea-induced unfolding process, while strong hydrophobic interactions between helices ?1 and ?3, and between ?2 and ?3, stabilize these regions even at very high concentrations of urea.

Julien, Olivier; Chatterjee, Subhrangsu; Thiessen, Angela; Graether, Steffen P; Sykes, Brian D

2009-01-01

243

Combined copper/zinc attachment to prion protein  

NASA Astrophysics Data System (ADS)

Misfolding of prion protein (PrP) is responsible for diseases such as ``mad-cow disease'' in cattle and Creutzfeldt-Jacob in humans. Extensive experimental investigation has established that this protein strongly interacts with copper ions, and this ability has been linked to its still unknown function. Attachment of other metal ions (zinc, iron, manganese) have been demonstrated as well, but none of them could outcompete copper. Recent finding, however, indicates that at intermediate concentrations both copper and zinc ions can attach to the PrP at the octarepeat region, which contains high affinity metal binding sites. Based on this evidence, we have performed density functional theory simulations to investigate the combined Cu/Zn attachment. We consider all previously reported binding modes of copper at the octarepeat region and examine a possibility simultaneous Cu/Zn attachment. We find that this can indeed occur for only one of the known binding sites, when copper changes its coordination mode to allow for attachment of zinc ion. The implications of the simultaneous attachment on neural function remain to be explored.

Hodak, Miroslav; Bernholc, Jerry

2013-03-01

244

Superoxide dismutase activity of Cu-bound prion protein  

NASA Astrophysics Data System (ADS)

Misfolding of the prion protein, PrP, has been linked to a group of neurodegenerative diseases, including the mad cow disease in cattle and the Creutzfeldt-Jakob disease in humans. The normal function of PrP is still unknown, but it was found that the PrP can efficiently bind Cu(II) ions. Early experiments suggested that Cu-PrP complex possesses significant superoxide dismutase (SOD) activity, but later experiments failed to confirm it and at present this issue remains unresolved. Using a recently developed hybrid DFT/DFT method, which combines Kohn-Sham DFT for the solute and its first solvation shells with orbital-free DFT for the remainder of the solvent, we have investigated SOD activity of PrP. The PrP is capable of incorporating Cu(II) ions in several binding modes and our calculations find that each mode has a different SOD activity. The highest activity found is comparable to those of well-known SOD proteins, suggesting that the conflicting experimental results may be due to different bindings of Cu(II) in those experiments.

Hodak, Miroslav; Lu, Wenchang; Bernholc, Jerry

2009-03-01

245

Alteration of NF-?B activity leads to mitochondrial apoptosis after infection with pathological prion protein  

PubMed Central

Nuclear factor kappa B (NF-?B) is a key regulator of the immune response, but in almost the same manner it is involved in induction of inflammation, proliferation and regulation of apoptosis. In the central nervous system activated NF-?B plays a neuroprotective role. While in some neurodegenerative disorders the role of NF-?B is well characterized, there is poor knowledge on the role of NF-?B in prion disease. We found binding but no transcriptional activity of the transcription factor in vitro. Characterizing the mechanism of cell death after infection with pathological prion protein increased caspase-9 and caspase-3 activity was detected and the lack of NF-?B activity resulted in the inability to activate target genes that usually play an important role in neuroprotection. Additionally, we investigated the role of NF-?B after prion infection of Nfkb1–/–, Nfkb2–/– and Bcl3–/– mice and central nervous system-specific p65-deleted mice revealing an accelerated prion disease in NF-?B2- and Bcl-3-deficient mice, which is in line with a reduced neuroprotective activity in prion infection. Based on our findings, we propose a model whereby the alteration of NF-?B activity at the early stages of infection with pathological prion protein leads to neuronal cell death mediated by mitochondrial apoptosis.

Bourteele, Soizic; Oesterle, Katja; Weinzierl, Andreas O; Paxian, Stephan; Riemann, Marc; Schmid, Roland M; Planz, Oliver

2007-01-01

246

Characterization of variant Creutzfeldt-Jakob disease prions in prion protein-humanized mice carrying distinct codon 129 genotypes.  

PubMed

To date, all clinical variant Creutzfeldt-Jakob disease (vCJD) patients are homozygous for methionine at polymorphic codon 129 (129M/M) of the prion protein (PrP) gene. However, the appearance of asymptomatic secondary vCJD infection in individuals with a PRNP codon 129 genotype other than M/M and transmission studies using animal models have raised the concern that all humans might be susceptible to vCJD prions, especially via secondary infection. To reevaluate this possibility and to analyze in detail the transmission properties of vCJD prions to transgenic animals carrying distinct codon 129 genotype, we performed intracerebral inoculation of vCJD prions to humanized knock-in mice carrying all possible codon 129 genotypes (129M/M, 129M/V, or 129V/V). All humanized knock-in mouse lines were susceptible to vCJD infection, although the attack rate gradually decreased from 129M/M to 129M/V and to 129V/V. The amount of PrP deposition including florid/amyloid plaques in the brain also gradually decreased from 129M/M to 129M/V and to 129V/V. The biochemical properties of protease-resistant abnormal PrP in the brain and transmissibility of these humanized mouse-passaged vCJD prions upon subpassage into knock-in mice expressing bovine PrP were not affected by the codon 129 genotype. These results indicate that individuals with the 129V/V genotype may be more susceptible to secondary vCJD infection than expected and may lack the neuropathological characteristics observed in vCJD patients with the 129M/M genotype. Besides the molecular typing of protease-resistant PrP in the brain, transmission studies using knock-in mice carrying bovine PrP may aid the differential diagnosis of secondary vCJD infection, especially in individuals with the 129V/V genotype. PMID:23792955

Takeuchi, Atsuko; Kobayashi, Atsushi; Ironside, James W; Mohri, Shirou; Kitamoto, Tetsuyuki

2013-06-21

247

Retrotranslocation of Prion Proteins from the Endoplasmic Reticulum by Preventing GPI Signal Transamidation  

PubMed Central

Neurodegeneration in diseases caused by altered metabolism of mammalian prion protein (PrP) can be averted by reducing PrP expression. To identify novel pathways for PrP down-regulation, we analyzed cells that had adapted to the negative selection pressure of stable overexpression of a disease-causing PrP mutant. A mutant cell line was isolated that selectively and quantitatively routes wild-type and various mutant PrPs for ER retrotranslocation and proteasomal degradation. Biochemical analyses of the mutant cells revealed that a defect in glycosylphosphatidylinositol (GPI) anchor synthesis leads to an unprocessed GPI-anchoring signal sequence that directs both ER retention and efficient retrotranslocation of PrP. An unprocessed GPI signal was sufficient to impart ER retention, but not retrotranslocation, to a heterologous protein, revealing an unexpected role for the mature domain in the metabolism of misprocessed GPI-anchored proteins. Our results provide new insights into the quality control pathways for unprocessed GPI-anchored proteins and identify transamidation of the GPI signal sequence as a step in PrP biosynthesis that is absolutely required for its surface expression. As each GPI signal sequence is unique, these results also identify signal recognition by the GPI-transamidase as a potential step for selective small molecule perturbation of PrP expression.

Ashok, Aarthi

2008-01-01

248

The Toxicity of the PrP106-126 Prion Peptide on Cultured Photoreceptors Correlates with the Prion Protein Distribution in the Mammalian and Human Retina  

PubMed Central

In patients affected by Creutzfeldt-Jakob disease and in animals affected by transmissible spongiform encephalopathies, retinal functions are altered, and major spongiform changes are observed in the outer plexiform layer where photoreceptors have their synaptic terminals. In the present study, the prion protein PrPc was found to form aggregates in rod photoreceptor terminals from both rat and human retina, whereas no labeling was observed in cone photoreceptors. Discrete staining was also detected in the inner plexiform layer where the prion protein was located at human amacrine cell synapses. In mixed porcine retinal cell cultures, the PrP106-126 prion peptide triggered a 61% rod photoreceptor cell loss by apoptosis as indicated by terminal deoxynucleotidyl transferase dUTP nick-end labeling, whereas cone photoreceptors were not affected. Amacrine cells were also reduced by 47% in contrast to ganglion cells. Although this cell loss was associated with a 5.5-fold increase in microglial cells, the strict correlation between the PrPc prion protein expression and the peptide toxicity suggested that this toxicity did not rely on the release of a toxic compound by glial cells. These results provide new insights into the retinal pathophysiology of prion diseases and illustrate advantages of adult retinal cell cultures to investigate prion pathogenic mechanisms.

Gong, Jie; Jellali, Abdeljelil; Forster, Valerie; Mutterer, Jerome; Dubus, Elisabeth; Altrock, Wilko D.; Sahel, Jose A.; Rendon, Alvaro; Picaud, Serge

2007-01-01

249

Molecular modelling indicates that the pathological conformations of prion proteins might be beta-helical.  

PubMed Central

Creutzfeldt-Jakob disease, kuru, scrapie and bovine spongiform encephalopathy are diseases of the mammalian central nervous system that involve the conversion of a cellular protein into an insoluble extracellular isoform. Spectroscopic studies have shown that the precursor protein contains mainly alpha-helical and random-coil conformations, whereas the prion isoform is largely in the beta conformation. The pathogenic prion is resistant to denaturation and protease digestion and can promote the conversion of the precursor protein to the pathogenic form. These properties have yet to be explained in terms of the structural conformations of the proteins. In the present study, molecular modelling showed that prion proteins could adopt the beta-helical conformation, which has been established for a number of fibrous proteins and has been suggested previously as the basis of amyloid fibrils. The beta-helical conformation provides explanations for the biophysical and biochemical stability of prions, their ability to form templates for the transmission of pathological conformation, and the existence of phenotypical strains of the prion diseases.

Downing, D T; Lazo, N D

1999-01-01

250

Distinct Type of Transmission Barrier Revealed by Study of Multiple Prion Determinants of Rnq1  

PubMed Central

Prions are self-propagating protein conformations. Transmission of the prion state between non-identical proteins, e.g. between homologous proteins from different species, is frequently inefficient. Transmission barriers are attributed to sequence differences in prion proteins, but their underlying mechanisms are not clear. Here we use a yeast Rnq1/[PIN+]-based experimental system to explore the nature of transmission barriers. [PIN+], the prion form of Rnq1, is common in wild and laboratory yeast strains, where it facilitates the appearance of other prions. Rnq1's prion domain carries four discrete QN-rich regions. We start by showing that Rnq1 encompasses multiple prion determinants that can independently drive amyloid formation in vitro and transmit the [PIN+] prion state in vivo. Subsequent analysis of [PIN+] transmission between Rnq1 fragments with different sets of prion determinants established that (i) one common QN-rich region is required and usually sufficient for the transmission; (ii) despite identical sequences of the common QNs, such transmissions are impeded by barriers of different strength. Existence of transmission barriers in the absence of amino acid mismatches in transmitting regions indicates that in complex prion domains multiple prion determinants act cooperatively to attain the final prion conformation, and reveals transmission barriers determined by this cooperative fold.

Kadnar, Michele L.; Articov, Gulnara; Derkatch, Irina L.

2010-01-01

251

Disruption of the X-loop turn of the prion protein linked to scrapie resistance  

PubMed Central

The prion diseases are a class of neurodegenerative diseases caused by the misfolding and aggregation of the prion protein (PrPC) into toxic and infectious oligomers (PrPSc). These oligomers are critical to understanding and combating these diseases. Differences in the sequence of PrP affect disease susceptibility, likely by shifting the tolerance of the protein for adaptation to PrPSc conformations and/or the recognition event between PrPSc and PrPC prior to conversion of the PrPC. We selected two sets of PrPSc-resistant mutant sequences for solvated atomistic molecular dynamics simulation to investigate the structural basis of resistance. The first group involved mutation in the X-loop (residues 164-171) resulting from selective breeding of sheep. The second group included eight mutants in mice identified by random mutagenesis targeting helix C followed by screening in cell cultures. Multiple simulations were performed of 14 different mutant and control constructs under different pH conditions for a total of 3.6 ?s of simulation time. The X-loop formed a stable turn at neutral pH in wild-type PrP from both species. PrPSc-resistant mutations disrupted this turn even though only one of the mutants is in the X-loop. The X-loop is compact and buried in our previously described spiral models of PrPSc-like oligomers. On the basis of the findings presented here and in the context of the spiral oligomer model, we propose that expansion of the X-loop disrupts protofibril packing, providing a structural basis for resistance.

Scouras, Alexander D.; Daggett, Valerie

2012-01-01

252

Conformational diversity in prion protein variants influences intermolecular ?-sheet formation  

PubMed Central

A conformational transition of normal cellular prion protein (PrPC) to its pathogenic form (PrPSc) is believed to be a central event in the transmission of the devastating neurological diseases known as spongiform encephalopathies. The common methionine/valine polymorphism at residue 129 in the PrP influences disease susceptibility and phenotype. We report here seven crystal structures of human PrP variants: three of wild-type (WT) PrP containing V129, and four of the familial variants D178N and F198S, containing either M129 or V129. Comparison of these structures with each other and with previously published WT PrP structures containing M129 revealed that only WT PrPs were found to crystallize as domain-swapped dimers or closed monomers; the four mutant PrPs crystallized as non-swapped dimers. Three of the four mutant PrPs aligned to form intermolecular ?-sheets. Several regions of structural variability were identified, and analysis of their conformations provides an explanation for the structural features, which can influence the formation and conformation of intermolecular ?-sheets involving the M/V129 polymorphic residue.

Lee, Seungjoo; Antony, Lizamma; Hartmann, Rune; Knaus, Karen J; Surewicz, Krystyna; Surewicz, Witold K; Yee, Vivien C

2010-01-01

253

Transport of the Pathogenic Prion Protein through Soils  

PubMed Central

Transmissible spongiform encephalopathies (TSEs) are progressive neurodegenerative diseases and include bovine spongiform encephalopathy of cattle, chronic wasting disease (CWD) of deer and elk, scrapie in sheep and goats, and Creutzfeldt-Jakob disease in humans. An abnormally folded form of the prion protein (designated PrPTSE) is typically associated with TSE infectivity and may constitute the major, if not sole, component of the infectious agent. Transmission of CWD and scrapie is mediated in part by an environmental reservoir of infectivity. Soil appears to be a plausible candidate for this reservoir. TSE agent transport through soil is expected to influence the accessibility of the pathogen to animals after deposition and must be understood to assess the risks associated with burial of infected carcasses. We report results of saturated column experiments designed to evaluate PrPTSE transport through five soils with relatively high sand or silt contents. Protease-treated TSE-infected brain homogenate was used as a model for PrPTSE present in decomposing infected tissue. Synthetic rainwater was used as the eluent. PrPTSE was retained by all five soils; no detectable PrPTSE was eluted over more than 40 pore volumes of flow. Lower bound apparent attachment coefficients were estimated for each soil. Our results suggest that TSE agent released from decomposing tissues would remain near the site of initial deposition. In the case of infected carcasses deposited on the land surface, this may result in local sources of infectivity to other animals.

Jacobson, Kurt H.; Lee, Seunghak; Somerville, Robert A.; McKenzie, Debbie; Benson, Craig H.; Pedersen, Joel A.

2011-01-01

254

Prion protein lacks robust cytoprotective activity in cultured cells  

PubMed Central

Background The physiological function of the cellular prion protein (PrPC) remains unknown. However, PrPC has been reported to possess a cytoprotective activity that prevents death of neurons and other cells after a toxic stimulus. To explore this effect further, we attempted to reproduce several of the assays in which a protective activity of PrP had been previously demonstrated in mammalian cells. Results In the first set of experiments, we found that PrP over-expression had a minimal effect on the death of MCF-7 breast carcinoma cells treated with TNF-? and Prn-p0/0 immortalized hippocampal neurons (HpL3-4 cells) subjected to serum deprivation. In the second set of assays, we observed only a small difference in viability between cerebellar granule neurons cultured from PrP-null and control mice in response to activation of endogenous or exogenous Bax. Conclusion Taken together, our results suggest either that cytoprotection is not a physiologically relevant activity of PrPC, or that PrPC-dependent protective pathways operative in vivo are not adequately modeled by these cell culture systems. We suggest that cell systems capable of mimicking the neurotoxic effects produced in transgenic mice by N-terminally deleted forms of PrP or Doppel may represent more useful tools for analyzing the cytoprotective function of PrPC.

Christensen, Heather M; Harris, David A

2008-01-01

255

Potential roles for prions and protein-only inheritance in cancer  

PubMed Central

Inherited mutations are known to cause familial cancers. However, the cause of sporadic cancers, which likely represent the majority of cancers, is yet to be elucidated. Sporadic cancers contain somatic mutations (including oncogenic mutations), however, the origin of these mutations is unclear. An intriguing possibility is that a stable alteration occurs in somatic cells prior to oncogenic mutations and promotes the subsequent accumulation of oncogenic mutations. This review explores the possible role of prions and protein-only inheritance in cancer. Genetic studies using lower eukaryotes, primarily yeast, have identified a large number of proteins as prions that confer dominant phenotypes with cytoplasmic (non-Mendelian) inheritance. Many of these have mammalian functional homologs. The human prion protein (PrP) is known to cause neurodegenerative diseases and has now been found to be up-regulated in multiple cancers. PrP expression in cancer cells contributes to cancer progression and resistance to various cancer therapies. Epigenetic changes in gene expression and hyper-activation of MAP kinase (MAPK) signalling, processes that in lower eukaryotes are affected by prions, play important roles in oncogenesis in humans. Prion phenomena in yeast appear to be influenced by stresses and there is considerable evidence for association of some amyloids with biologically positive functions. This suggests that if protein-only somatic inheritance exists in mammalian cells, it might contribute to cancer phenotypes. Here we highlight evidence in the literature for an involvement of prion or prion-like mechanisms in cancer and how they may in the future be viewed as diagnostic markers and potential therapeutic targets.

Antony, H; Wiegmans, AP; Wei, MQ; Chernoff, YO; Khanna, KK; Munn, AL

2011-01-01

256

Accumulation and dissemination of prion protein in experimental sheep scrapie in the natural host  

PubMed Central

Background In order to study the sites of uptake and mechanisms of dissemination of scrapie prions in the natural host under controlled conditions, lambs aged 14 days and homozygous for the VRQ allele of the PrP gene were infected by the oral route. Infection occurred in all lambs with a remarkably short and highly consistent incubation period of approximately 6 months. Challenge of lambs at approximately eight months of age resulted in disease in all animals, but with more variable incubation periods averaging significantly longer than those challenged at 14 days. This model provides an excellent system in which to study the disease in the natural host by virtue of the relatively short incubation period and close resemblance to natural infection. Results Multiple sites of prion uptake were identified, of which the most important was the Peyer's patch of the distal ileum. Neuroinvasion was detected initially in the enteric nervous system prior to infection of the central nervous system. At end stage disease prion accumulation was widespread throughout the entire neuraxis, but vacuolar pathology was absent in most animals that developed disease at 6–7 months of age. Conclusion Initial spread of detectable PrP was consistent with drainage in afferent lymph to dependent lymph nodes. Subsequent accumulation of prions in lymphoid tissue not associated with the gut is consistent with haematogenous spread. In addition to macrophages and follicular dendritic cells, prion containing cells consistent with afferent lymph dendritic cells were identified and are suggested as a likely vehicle for carriage of prions from initial site of uptake to the lymphoreticular system, and as potential carriers of prion protein in blood. It is apparent that spongiform change, the characteristic lesion of scrapie and other prion diseases, is not responsible for the clinical signs in sheep, but may develop in an age dependent manner.

Ryder, Stephen J; Dexter, Glenda E; Heasman, Lindsay; Warner, Richard; Moore, S Jo

2009-01-01

257

Fatal Familial Insomnia and Familial Creutzfeldt-Jakob Disease: Different Prion Proteins Determined by a DNA Polymorphism  

Microsoft Academic Search

Fatal familial insomnia and a subtype of Creutzfeldt-Jakob disease, two clinically and pathologically distinct diseases, are linked to the same mutation at codon 178 (Asp-178 --> Asn) but segregate with different genotypes determined by this mutation and the methionine-valine polymorphism at codon 129 of the prion protein gene. The abnormal isoforms of the prion protein in these two diseases were

Lucia Monari; Shu G. Chen; Paul Brown; Piero Parchi; Robert B. Petersen; Jacqueline Mikol; Franscoise Gray; Pietro Cortelli; Pasquale Montagna; Bernardino Ghetti; Lev G. Goldfarb; D. Carleton Gajdusek; Elio Lugaresi; Pierluigi Gambetti; Lucila Autilio-Gambetti

1994-01-01

258

Prion protein accumulation in the spinal cords of patients with sporadic and growth hormone associated Creutzfeldt-Jakob disease  

Microsoft Academic Search

An immunohistological study of the spinal cord in 20 cases of sporadic and 4 iatrogenic (growth hormone) cases of Creutzfeldt-Jakob (CJD) disease patients was performed to detect the presence of disease specific prion protein using a number of different antisera. Prion protein was present in all the growth hormone recipients and in 11 of the 20 sporadic CJD cases. Plaque-like

I. A. Goodbrand; J. W. Ironside; D. Nicolson; J. E. Bell

1995-01-01

259

Unique Structural Characteristics of the Rabbit Prion Protein*  

PubMed Central

Rabbits are one of the few mammalian species that appear to be resistant to transmissible spongiform encephalopathies due to the structural characteristics of the rabbit prion protein (RaPrPC) itself. Here, we determined the solution structures of the recombinant protein RaPrPC-(91–228) and its S173N variant and detected the backbone dynamics of their structured C-terminal domains-(121–228). In contrast to many other mammalian PrPCs, loop 165–172, which connects ?-sheet-2 and ?-helix-2, is well-defined in RaPrPC. For the first time, order parameters S2 are obtained for residues in this loop region, indicating that loop 165–172 of RaPrPC is highly ordered. Compared with the wild-type RaPrPC, less hydrogen bonds form in the S173N variant. The NMR dynamics analysis reveals a distinct increase in the structural flexibility of loop 165–172 and helix-3 after the S173N substitution, implying that the S173N substitution disturbs the long range interaction of loop 165–172 with helix-3, which further leads to a marked decrease in the global conformational stability. Significantly, RaPrPC possesses a unique charge distribution, carrying a continuous area of positive charges on the surface, which is distinguished from other PrPCs. The S173N substitution causes visible changes of the charge distribution around the recognition sites for the hypothetical protein X. Our results suggest that the ordered loop 165–172 and its interaction with helix-3, together with the unique distribution of surface electrostatic potential, significantly contribute to the unique structural characteristics of RaPrPC.

Wen, Yi; Li, Jun; Yao, Wenming; Xiong, Minqian; Hong, Jing; Peng, Yu; Xiao, Gengfu; Lin, Donghai

2010-01-01

260

Prion Dynamics and the Quest for the Genetic Determinant in Protein-Only Inheritance  

PubMed Central

According to the prion hypothesis, proteins may act in atypical roles as genetic elements of infectivity and inheritance by undergoing self-replicating changes in physical state. While the preponderance of evidence strongly supports this concept particularly in fungi, the detailed mechanisms by which distinct protein forms specify unique phenotypes are emerging concepts. A particularly active area of investigation is the molecular nature of the heritable species, which has been probed through genetic, biochemical, and cell biological experimentation as well as by mathematical modeling. Here, we suggest that these studies are converging to implicate small aggregates composed of prion-state conformers as the transmissible genetic determinants of protein-based phenotypes.

Sindi, Suzanne S.

2009-01-01

261

Neuroimmunoendocrine Regulation of the Prion Protein in Neutrophils*  

PubMed Central

The prion protein (PrPC) is a cell surface protein expressed mainly in the nervous system. In addition to the role of its abnormal conformer in transmissible spongiform encephalopathies, normal PrPC may be implicated in other degenerative conditions often associated with inflammation. PrPC is also present in cells of hematopoietic origin, including T cells, dendritic cells, and macrophages, and it has been shown to modulate their functions. Here, we investigated the impact of inflammation and stress on the expression and function of PrPC in neutrophils, a cell type critically involved in both acute and chronic inflammation. We found that systemic injection of LPS induced transcription and translation of PrPC in mouse neutrophils. Up-regulation of PrPC was dependent on the serum content of TGF-? and glucocorticoids (GC), which, in turn, are contingent on the activation of the hypothalamic-pituitary-adrenal axis in response to systemic inflammation. GC and TGF-?, either alone or in combination, directly up-regulated PrPC in neutrophils, and accordingly, the blockade of GC receptors in vivo curtailed the LPS-induced increase in the content of PrPC. Moreover, GC also mediated up-regulation of PrPC in neutrophils following noninflammatory restraint stress. Finally, neutrophils with up-regulated PrPC presented enhanced peroxide-dependent cytotoxicity to endothelial cells. The data demonstrate a novel interplay of the nervous, endocrine, and immune systems upon both the expression and function of PrPC in neutrophils, which may have a broad impact upon the physiology and pathology of various organs and systems.

Mariante, Rafael M.; Nobrega, Alberto; Martins, Rodrigo A. P.; Areal, Romulo B.; Bellio, Maria; Linden, Rafael

2012-01-01

262

Lack of TAR-DNA binding protein-43 (TDP-43) pathology in human prion diseases  

PubMed Central

Aims TAR-DNA binding protein-43 (TDP-43) is the major ubiquitinated protein in the aggregates in frontotemporal dementia with ubiquitin-positive, tau-negative inclusions and motor neurone disease. Abnormal TDP-43 immunoreactivity has also been described in Alzheimer's disease, Lewy body diseases and Guam parkinsonism–dementia complex. We therefore aimed to determine whether there is TDP-43 pathology in human prion diseases, which are characterised by variable deposition of prion protein (PrP) aggregates in the brain as amyloid plaques or more diffuse deposits. Material and methods TDP-43, ubiquitin and PrP were analysed by immunohistochemistry and double-labelling immunofluorescence, in sporadic, acquired and inherited forms of human prion disease. Results Most PrP plaques contained ubiquitin, while synaptic PrP deposits were not associated with ubiquitin. No abnormal TDP-43 inclusions were identified in any type of prion disease case, and TDP-43 did not co-localize with ubiquitin-positive PrP plaques or with diffuse PrP aggregates. Conclusions These data do not support a role for TDP-43 in prion disease pathogenesis and argue that TDP-43 inclusions define a distinct group of neurodegenerative disorders.

Isaacs, A M; Powell, C; Webb, T E; Linehan, J M; Collinge, J; Brandner, S

2008-01-01

263

Amyloid fibril formation and protein misassembly: a structural quest for insights into amyloid and prion diseases  

Microsoft Academic Search

The assembly and misassembly of normally soluble proteins into fibrilar structures is thought to be a causative agent in a variety of human amyloid and prion diseases. Structural and mechanistic studies of this process are beginning to elucidate the conformational changes required for the conversion of a normally soluble and functional protein into a defined quaternary structure.

Jeffery W Kelly

1997-01-01

264

Antibodies inhibit prion propagation and clear cell cultures of prion infectivity  

Microsoft Academic Search

Prions are the transmissible pathogenic agents responsible for diseases such as scrapie and bovine spongiform encephalopathy. In the favoured model of prion replication, direct interaction between the pathogenic prion protein (PrPSc) template and endogenous cellular prion protein (PrPC) is proposed to drive the formation of nascent infectious prions. Reagents specifically binding either prion-protein conformer may interrupt prion production by inhibiting

David Peretz; R. Anthony Williamson; Kiotoshi Kaneko; Julie Vergara; Estelle Leclerc; Gerold Schmitt-Ulms; Ingrid R. Mehlhorn; Giuseppe Legname; Mark R. Wormald; Pauline M. Rudd; Raymond A. Dwek; Dennis R. Burton

2001-01-01

265

The tip of the iceberg: RNA-binding proteins with prion-like domains in neurodegenerative disease  

PubMed Central

Prions are self-templating protein conformers that are naturally transmitted between individuals and promote phenotypic change. In yeast, prion-encoded phenotypes can be beneficial, neutral or deleterious depending upon genetic background and environmental conditions. A distinctive and portable ‘prion domain’ enriched in asparagine, glutamine, tyrosine and glycine residues unifies the majority of yeast prion proteins. Deletion of this domain precludes prionogenesis and appending this domain to reporter proteins can confer prionogenicity. An algorithm designed to detect prion domains has successfully identified 19 domains that can confer prion behavior. Scouring the human genome with this algorithm enriches a select group of RNA-binding proteins harboring a canonical RNA recognition motif (RRM) and a putative prion domain. Indeed, of 210 human RRM-bearing proteins, 29 have a putative prion domain, and 12 of these are in the top 60 prion candidates in the entire genome. Startlingly, these RNA-binding prion candidates are inexorably emerging, one by one, in the pathology and genetics of devastating neurodegenerative disorders, including: amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U), Alzheimer’s disease and Huntington’s disease. For example, FUS and TDP-43, which rank 1st and 10th among RRM-bearing prion candidates, form cytoplasmic inclusions in the degenerating motor neurons of ALS patients and mutations in TDP-43 and FUS cause familial ALS. Recently, perturbed RNA-binding proteostasis of TAF15, which is the 2nd ranked RRM-bearing prion candidate, has been connected with ALS and FTLD-U. We strongly suspect that we have now merely reached the tip of the iceberg. We predict that additional RNA-binding prion candidates identified by our algorithm will soon surface as genetic modifiers or causes of diverse neurodegenerative conditions. Indeed, simple prion-like transfer mechanisms involving the prion-like domains of RNA-binding proteins could underlie the classical non-cell-autonomous emanation of neurodegenerative pathology from originating epicenters to neighboring portions of the nervous system.

King, Oliver D.; Gitler, Aaron D.; Shorter, James

2012-01-01

266

A comparative molecular dynamics study on thermostability of human and chicken prion proteins  

SciTech Connect

To compare the thermostabilities of human and chicken normal cellular prion proteins (HuPrP{sup C} and CkPrP{sup C}), molecular dynamics (MD) simulations were performed for both proteins at an ensemble level (10 parallel simulations at 400 K and 5 parallel simulations at 300 K as a control). It is found that the thermostability of HuPrP{sup C} is comparable with that of CkPrP{sup C}, which implicates that the non-occurrence of prion diseases in non-mammals cannot be completely attributed to the thermodynamic properties of non-mammalian PrP{sup C}.

Ji, Hong-Fang [Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Center for Advanced Study, Shandong University of Technology, Zibo 255049 (China); Zhang, Hong-Yu [Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Center for Advanced Study, Shandong University of Technology, Zibo 255049 (China)]. E-mail: zhanghy@sdut.edu.cn

2007-08-03

267

Induction of antibodies against human prion proteins (PrP) by DNA-mediated immunization of PrP 0 0 mice  

Microsoft Academic Search

Prion diseases are neurodegenerative disorders, affecting humans and animals. The human diseases include kuru, Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), and fatal familial insomnia (FFI). To generate monospecific antisera against human prion proteins we have immunized mice with DNA coding for different human prion proteins. We constructed immunization vectors expressing individual genotypes of either the cellular prion gene (PRNP) or

Susanne Krasemann; Martin Groschup; Gerhard Hunsmann; Walter Bodemer

1996-01-01

268

Comparative analysis of essential collective dynamics and NMR-derived flexibility profiles in evolutionarily diverse prion proteins  

PubMed Central

Collective motions on ns-µs time scales are known to have a major impact on protein folding, stability, binding and enzymatic efficiency. It is also believed that these motions may have an important role in the early stages of prion protein misfolding and prion disease. In an effort to accurately characterize these motions and their potential influence on the misfolding and prion disease transmissibility we have conducted a combined analysis of molecular dynamic simulations and NMR-derived flexibility measurements over a diverse range of prion proteins. Using a recently developed numerical formalism, we have analyzed the essential collective dynamics (ECD) for prion proteins from eight different species including human, cow, elk, cat, hamster, chicken, turtle and frog. We also compared the numerical results with flexibility profiles generated by the random coil index (RCI) from NMR chemical shifts. Prion protein backbone flexibility derived from experimental NMR data and from theoretical computations show strong agreement with each other, demonstrating that it is possible to predict the observed RCI profiles employing the numerical ECD formalism. Interestingly, flexibility differences in the loop between second b strand (S2) and the second a helix (HB) appear to distinguish prion proteins from species that are susceptible to prion disease and those that are resistant. Our results show that the different levels of flexibility in the S2-HB loop in various species are predictable via the ECD method, indicating that ECD may be used to identify disease resistant variants of prion proteins, as well as the influence of prion proteins mutations on disease susceptibility or misfolding propensity.

Santo, Kolattukudy P; Berjanskii, Mark; Wishart, David S

2011-01-01

269

Prion disease genetics  

Microsoft Academic Search

Prion diseases have stimulated intense scientific scrutiny since it was proposed that the infectious agent was devoid of nucleic acid. Despite this finding, genetics has played a key role in understanding the pathobiology and clinical aspects of prion disease through the effects of a series of polymorphisms and mutations in the prion protein gene (PRNP). The advent of variant Creutzfeldt–Jakob

Simon Mead

2006-01-01

270

Influence of the N-terminal domain on the aggregation properties of the prion protein  

PubMed Central

Prion diseases appear to be caused by the aggregation of the cellular prion protein (PrPC) into an infectious form denoted PrPSc. The in vitro aggregation of the prion protein has been extensively investigated, yet many of these studies utilize truncated polypeptides. Because the C-terminal portion of PrPSc is protease-resistant and retains infectivity, it is assumed that studies on this fragment are most relevant. The full-length protein can be distinguished from the truncated protein because it contains a largely structured, ?-helical, C-terminal region in addition to an N terminus that is unstructured in the absence of metal ion binding. Herein, the in vitro aggregation of a truncated portion of the prion protein (PrP 90–231) and a full-length version (PrP 23–231) were compared. In each case, concentration-dependent aggregation was analyzed to discern whether it proceeds by a nucleation-dependent pathway. Both protein constructs appear to aggregate via a nucleated polymerization with a small nucleus size, yet the later steps differ. The full-length protein forms larger aggregates than the truncated protein, indicating that the N terminus may mediate higher-order aggregation processes. In addition, the N terminus has an influence on the assembly state of PrP before aggregation begins, causing the full-length protein to adopt several oligomeric forms in a neutral pH buffer. Our results emphasize the importance of studying the full-length protein in addition to the truncated forms for in vitro aggregation studies in order to make valid hypotheses about the mechanisms of prion aggregation and the distribution of aggregates in vivo.

Frankenfield, Kristen N.; Powers, Evan T.; Kelly, Jeffery W.

2005-01-01

271

Does the prion protein gene 129 codon polymorphism influence sleep? Evidence from a fatal familial insomnia kindred  

Microsoft Academic Search

Objective: Experimental and clinical evidence in prion diseases suggests that the prion protein gene (PRNP) plays a role in regulating sleep.Methods: Seventeen healthy individuals belonging to a single fatal familial insomnia pedigree, 8 carriers and 9 non-carriers of the PRNP codon 178 mutation, underwent polysomnography and spectral electroencephalographic (EEG) analysis. All were also characterized with regard to the codon 129

Giuseppe Plazzi; Pasquale Montagna; Manolo Beelke; Lino Nobili; Fabrizio De Carli; Pietro Cortelli; Stefano Vandi; Patrizia Avoni; Paolo Tinuper; Pierluigi Gambetti; Elio Lugaresi; Franco Ferrillo

2002-01-01

272

MANGANESE UPREGULATES CELLULAR PRION PROTEINS AND INHIBITS THE RATE OF PROTEINASE-K DEPENDENT LIMITED PROTEOLYSIS IN NEURONAL CELLS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The key event in the pathogenesis of prion diseases is the conversion of normal cellular prion proteins (PrP**c) to the proteinase K (PK) resistant, abnormal form (PrP**sc); however, the cellular mechanisms underlying the conversion remain enigmatic. Binding of divalent cations such as copper to th...

273

Clinical features in prion protein-deficient and wild-type cattle inoculated with transmissible mink encephalopathy (TME)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background: Transmissible spongiform encephalopathies (TSEs) or prion diseases are caused by the propagation of a misfolded form (PrP**d) of the normal cellular prion protein, PrP**c. Recently, we have reported the generation and characterization of PrP**C-deficient cattle (PrP-/-) produced by a seq...

274

Dual conformation of H2H3 domain of prion protein in mammalian cells.  

PubMed

The concept of prion is applied to protein modules that share the ability to switch between at least two conformational states and transmit one of these through intermolecular interaction and change of conformation. Although much progress has been achieved through the understanding of prions from organisms such as Saccharomyces cerevisiae, Podospora anserina, or Aplysia californica, the criteria that qualify a protein module as a prion are still unclear. In addition, the functionality of known prion domains fails to provide clues to understand the first identified prion, the mammalian infectious prion protein, PrP. To address these issues, we generated mammalian cellular models of expression of the C-terminal two helices of PrP, H2 and H3, which have been hypothesized, among other models, to hold the replication and conversion properties of the infectious PrP. We found that the H2H3 domain is an independent folding unit that undergoes glycosylations and glycosylphosphatidylinositol anchoring similar to full-length PrP. Surprisingly, in some conditions the normally folded H2H3 was able to systematically go through a conversion process and generate insoluble proteinase K-resistant aggregates. This structural switch involves the assembly of amyloid structures that bind thioflavin S and oligomers that are reactive to A11 antibody, which specifically detects protein oligomers from neurological disorders. Overall, we show that H2H3 is a conformational switch in a cellular context and is thus suggested to be a candidate for the conversion domain of PrP. PMID:21911495

Xu, Zhou; Prigent, Stéphanie; Deslys, Jean-Philippe; Rezaei, Human

2011-09-12

275

[Prion disease].  

PubMed

Human prion diseases are classified into 3 categories according to etiologies: idiopathic of unknown cause, acquired of infectious origin, and genetic by PRNP mutation. The surveillance committee have analyzed 2,494 cases and identified 1,402 as prion diseases. Most of them are idiopathic, namely sporadic CJD (77%) with less genetic and acquired prion diseases (17% and 5%, respectively). The number of patients identified by the surveillance committee in these years is about 120 which are less than the number of annual death of prion disease. The difference might be due to partly the fact our surveillance need the consent from patients' family and is not complete. The mean age at onset of prion disease is late 60s while the range is fairly wide. Brain MRIs and increase of CSF 14-3-3 and tau protein levels are very characteristic. Classical sporadic CJD could show completely normal T1WI with patchy high signals in the cerebral cortex and basal ganglia on DWI. In Japan, classical sporadic CJD (MM1) is most popular but there are some rare atypical subtypes. Among them, MM2-thalamic CJD is hardest to diagnose because it shows no high intensity signals on DWI, in addition to frequent absence of CSF and EEG characteristics. In this case, CBF decrease in the thalamus on SPECT is very helpful. Genetic prion diseases in Japan are quite distinct from those in Europe. V180I and M232R mutations are unique to Japan and show sporadic CJD phenotype. Dura graft-associated CJD (dCJD) are composed of 67% of classical sporadic CJD phenotype and 33% of atypical phenotype showing slower progression with amyloid plaques. Trace-back experiments suggested the PrP(sc) of the atypical dCJD was likely to be modified from infection of abnormal VV2 protein. Although there are some atypical forms of prion diseases as mentioned above, almost all prion cases could be diagnosed with EEG, MRI, genetic test, CSF test and SPECT. We also have some incidents in which brain surgery was done before the diagnosis of prion disease and many other patients were operated using the same operating instruments before their sterilization against prion disease had been done. The explanation of possibility of prion disease infection to the patients and their follow-up was started by the incident committee. It is very important for all the nations to cooperate with each other in order to overcome this intractable disease. PMID:21921445

Mizusawa, Hidehiro

2010-11-01

276

Motor behavioral and neuropathological deficits in mice deficient for normal prion protein expression  

PubMed Central

Summary It has been difficult to reconcile the absence of pathology and apparently normal behavior of mice lacking prion protein (PrP), referred to as Prnp0/0 mice, with a mechanism of prion pathogenesis involving progressive loss of PrPC-mediated neuroprotection. However, here we report that Prnp0/0 mice exhibit significant age-related defects in motor coordination and balance compared with mice expressing wild type Prnp on a syngeneic background, and that the brains of behaviorally-impaired Prnp0/0 mice display the cardinal neuropathological hallmarks of spongiform pathology and reactive astrocytic gliosis that normally accompany prion disease. Consistent with the appearance of cerebellar ataxia as an early symptom in an patients with Gerstmann-Sträussler-Scheinker syndrome (GSS), an inherited form of human prion disease, motor coordination and balance defects manifested in a transgenic (Tg) mouse model of GSS considerably earlier than the onset of end-stage neurodegenerative disease. Our results are consistent with a mechanism in which loss of normal PrPC function is an important pathological component of prion diseases.

Nazor, Karah E.; Seward, Tanya; Telling, Glenn C.

2010-01-01

277

Prion Domain of Yeast Ure2 Protein Adopts a Completely Disordered Structure: A Solid-Support EPR Study  

PubMed Central

Amyloid fibril formation is associated with a range of neurodegenerative diseases in humans, including Alzheimer’s, Parkinson’s, and prion diseases. In yeast, amyloid underlies several non-Mendelian phenotypes referred to as yeast prions. Mechanism of amyloid formation is critical for a complete understanding of the yeast prion phenomenon and human amyloid-related diseases. Ure2 protein is the basis of yeast prion [URE3]. The Ure2p prion domain is largely disordered. Residual structures, if any, in the disordered region may play an important role in the aggregation process. Studies of Ure2p prion domain are complicated by its high aggregation propensity, which results in a mixture of monomer and aggregates in solution. Previously we have developed a solid-support electron paramagnetic resonance (EPR) approach to address this problem and have identified a structured state for the Alzheimer’s amyloid-? monomer. Here we use solid-support EPR to study the structure of Ure2p prion domain. EPR spectra of Ure2p prion domain with spin labels at every fifth residue from position 10 to position 75 show similar residue mobility profile for denaturing and native buffers after accounting for the effect of solution viscosity. These results suggest that Ure2p prion domain adopts a completely disordered structure in the native buffer. A completely disordered Ure2p prion domain implies that the amyloid formation of Ure2p, and likely other Q/N-rich yeast prion proteins, is primarily driven by inter-molecular interactions.

Ngo, Sam; Chiang, Vicky; Ho, Elaine; Le, Linh; Guo, Zhefeng

2012-01-01

278

Doped diamond-like carbon coatings for surgical instruments reduce protein and prion-amyloid biofouling and improve subsequent cleaning  

Microsoft Academic Search

Doped diamond-like carbon (DLC) coatings offer potential antifouling surfaces against microbial and protein attachment. In particular, stainless steel surgical instruments are subject to tissue protein and resilient prion protein attachment, making decontamination methods used in sterile service departments ineffective, potentially increasing the risk of iatrogenic Creutzfeldt-Jakob disease during surgical procedures. This study examined the adsorption of proteins and prion-associated amyloid

T. J. Secker; R. Hervé; Q. Zhao; K. B. Borisenko; E. W. Abel; C. W. Keevil

2012-01-01

279

Roles of endoproteolytic ?-cleavage and shedding of the prion protein in neurodegeneration.  

PubMed

The cellular prion protein (PrP(C)) plays important roles in neurodegenerative diseases. First, it is the well-established substrate for the conformational conversion into its pathogenic isoform (PrP(Sc)) giving rise to progressive and fatal prion diseases. Moreover, several recent reports highlight important roles of PrP(C) in other neurodegenerative conditions such as Alzheimer's disease. Since PrP(C) is subject to proteolytic processing, here we discuss the two main cleavage events under physiological conditions, ?-cleavage and shedding. We focus on how these cleavages and the resulting fragments may impact prion diseases as well as other neurodegenerative proteinopathies. Finally, we discuss the recently identified sheddase of PrP(C), namely the metalloprotease ADAM10, with regard to therapeutic potential against neurodegenerative diseases. PMID:23413979

Altmeppen, Hermann C; Prox, Johannes; Puig, Berta; Dohler, Frank; Falker, Clemens; Krasemann, Susanne; Glatzel, Markus

2013-03-13

280

Inactivation of prion proteins via covalent grafting with methoxypoly(ethylene glycol).  

PubMed

Transmissible spongiform encephalopathies (TSE) such as bovine spongiform encephalitis (BSE), Creutzfeld-Jakob disease (CJD) as well as other proteinaceous infectious particles (prions) mediated diseases have emerged as a significant concern in transfusion medicine. This concern is derived from both the disease causing potential of prion contaminated blood products but also due to tremendous impact of the active deferral of current and potential blood donors due to their extended stays in BSE prevalent countries (e.g., the United Kingdom). To date, there are no effective means by which infectious prion proteins can be inactivated in cellular and acellular blood products. Based on current work on the covalent grafting of methoxypoly(ethylene glycol) [mPEG] to proteins, viruses, and anuclear, and nucleated cells, it is hypothesized that the conversion of the normal PrP protein to its mutant conformation can be prevented by the covalent grafting of mPEG to the mutant protein. Inactivation of infective protein particles (prions) in both cellular blood products as well as cell free solutions (e.g., clotting factors) could be of medical/commercial value. It is hypothesized that consequent to the covalent modification of donor-derived prions with mPEG the requisite nucleation of the normal and mutant PrP proteins is inhibited due to the increased solubility of the modified mutant PrP and that the conformational conversion arising from the mutant PrP is prevented due to obscuration of protein charge by the heavily hydrated and neutral mPEG polymers, as well as by direct steric hindrance of the interaction due to the highly mobile polymer graft. PMID:16242248

Scott, Mark D

2005-10-19

281

Surface charge of polyoxometalates modulates polymerization of the scrapie prion protein.  

PubMed

Prions are composed solely of an alternatively folded isoform of the prion protein (PrP), designated PrP(Sc). N-terminally truncated PrP(Sc), denoted PrP 27-30, retains infectivity and polymerizes into rods with the ultrastructural and tinctorial properties of amyloid. We report here that some polyoxometalates (POMs) favor polymerization of PrP 27-30 into prion rods, whereas other POMs promote assembly of the protein into 2D crystals. Antibodies reacting with epitopes in denatured PrP 27-30 also bound to 2D crystals treated with 3 M urea. These same antibodies did not bind to either native PrP(Sc) or untreated 2D crystals. By using small, spherical POMs with Keggin-type structures, the central heteroatom was found to determine whether prion rods or 2D crystals were preferentially formed. An example of a Keggin-type POM with a phosphorous heteroatom is the phosphotungstate anion (PTA). Both PTA and a Keggin-type POM with a silicon heteratom have low-charge densities and favor formation of prion rods. In contrast, POMs with boron or hydrogen heteroatoms exhibiting higher negative charges encouraged 2D crystal formation. The 2D crystals of PrP 27-30 produced by selective precipitation with POMs were larger and more well ordered than those obtained by sucrose gradient centrifugation. Our findings argue that the negative charge of Keggin-type POMs determines the quaternary structure adopted by PrP 27-30. The mechanism by which POMs function in competing prion polymerization pathways--one favoring 2D crystals and the other, amyloid fibrils--remains to be established. PMID:19223590

Wille, Holger; Shanmugam, Maheswaran; Murugesu, Muralee; Ollesch, Julian; Stubbs, Gerald; Long, Jeffrey R; Safar, Jiri G; Prusiner, Stanley B

2009-02-17

282

Surface charge of polyoxometalates modulates polymerization of the scrapie prion protein  

PubMed Central

Prions are composed solely of an alternatively folded isoform of the prion protein (PrP), designated PrPSc. N-terminally truncated PrPSc, denoted PrP 27–30, retains infectivity and polymerizes into rods with the ultrastructural and tinctorial properties of amyloid. We report here that some polyoxometalates (POMs) favor polymerization of PrP 27-30 into prion rods, whereas other POMs promote assembly of the protein into 2D crystals. Antibodies reacting with epitopes in denatured PrP 27-30 also bound to 2D crystals treated with 3 M urea. These same antibodies did not bind to either native PrPSc or untreated 2D crystals. By using small, spherical POMs with Keggin-type structures, the central heteroatom was found to determine whether prion rods or 2D crystals were preferentially formed. An example of a Keggin-type POM with a phosphorous heteroatom is the phosphotungstate anion (PTA). Both PTA and a Keggin-type POM with a silicon heteratom have low-charge densities and favor formation of prion rods. In contrast, POMs with boron or hydrogen heteroatoms exhibiting higher negative charges encouraged 2D crystal formation. The 2D crystals of PrP 27-30 produced by selective precipitation with POMs were larger and more well ordered than those obtained by sucrose gradient centrifugation. Our findings argue that the negative charge of Keggin-type POMs determines the quaternary structure adopted by PrP 27-30. The mechanism by which POMs function in competing prion polymerization pathways—one favoring 2D crystals and the other, amyloid fibrils—remains to be established.

Wille, Holger; Shanmugam, Maheswaran; Murugesu, Muralee; Ollesch, Julian; Stubbs, Gerald; Long, Jeffrey R.; Safar, Jiri G.; Prusiner, Stanley B.

2009-01-01

283

Detection of Prion Protein Particles in Blood Plasma of Scrapie Infected Sheep  

PubMed Central

Prion diseases are transmissible neurodegenerative diseases affecting humans and animals. The agent of the disease is the prion consisting mainly, if not solely, of a misfolded and aggregated isoform of the host-encoded prion protein (PrP). Transmission of prions can occur naturally but also accidentally, e.g. by blood transfusion, which has raised serious concerns about blood product safety and emphasized the need for a reliable diagnostic test. In this report we present a method based on surface-FIDA (fluorescence intensity distribution analysis), that exploits the high state of molecular aggregation of PrP as an unequivocal diagnostic marker of the disease, and show that it can detect infection in blood. To prepare PrP aggregates from blood plasma we introduced a detergent and lipase treatment to separate PrP from blood lipophilic components. Prion protein aggregates were subsequently precipitated by phosphotungstic acid, immobilized on a glass surface by covalently bound capture antibodies, and finally labeled with fluorescent antibody probes. Individual PrP aggregates were visualized by laser scanning microscopy where signal intensity was proportional to aggregate size. After signal processing to remove the background from low fluorescence particles, fluorescence intensities of all remaining PrP particles were summed. We detected PrP aggregates in plasma samples from six out of ten scrapie-positive sheep with no false positives from uninfected sheep. Applying simultaneous intensity and size discrimination, ten out of ten samples from scrapie sheep could be differentiated from uninfected sheep. The implications for ante mortem diagnosis of prion diseases are discussed.

Reinartz, Elke; Jaeger, Karl-Erich; Langeveld, Jan P. M.; Rohwer, Robert G.; Gregori, Luisa; Terry, Linda A.; Willbold, Dieter; Riesner, Detlev

2012-01-01

284

IMMUNOHISTOCHEMICAL DETECTION AND DISTRIBUTION OF PRION PROTEIN IN A GOAT WITH NATURAL SCRAPIE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Formalin-fixed, paraffin-embedded tissue sections from a 3-year-old female Angora goat suffering from clinical scrapie were immunostained using a monoclonal antibody (mAb, F99/97.6.1; IgG1) specific for a conserved epitope on the prion protein. Widespread and prominent deposition of the scrapie iso...

285

Ultra-Sensitive Detection of Prion Protein in Blood Using Isothermal Amplification Technology.  

National Technical Information Service (NTIS)

The detection of the pathologic prion protein that is Implicated in transmissible spongiform encephalopathies (TSEs) is necessary to diagnose the disease. Presently, the Western Blot or ELISA are used to test the brain stem in cattle for the presence of p...

N. T. Constantine

2004-01-01

286

Prion Protein M129V Polymorphism Affects Retrieval-Related Brain Activity  

ERIC Educational Resources Information Center

|The prion protein Met129Val polymorphism has recently been related to human long-term memory with carriers of either the 129[superscript MM] or the 129[superscript MV] genotype recalling 17% more words than 129[superscript VV] carriers at 24 h following learning. Here, we sampled genotype differences in retrieval-related brain activity at 30 min…

Buchmann, Andreas; Mondadori, Christian R. A.; Hanggi, Jurgen; Aerni, Amanda; Vrticka, Pascal; Luechinger, Roger; Boesiger, Peter; Hock, Christoph; Nitsch, Roger M.; de Quervain, Dominique J.-F.; Papassotiropoulos, Andreas; Henke, Katharina

2008-01-01

287

Prion propagation in mice expressing human and chimeric PrP transgenes implicates the interaction of cellular PrP with another protein  

Microsoft Academic Search

Transgenic (Tg) mice expressing human (Hu) and chimeric prion protein (PrP) genes were inoculated with brain extracts from humans with inherited or sporadic prion disease to investigate the mechanism by which PrPc is transformed into PrPSc. Although Tg(HuPrP) mice expressed high levels of HuPrPc, they were resistant to human prions. They became susceptible to human prions upon ablation of the

Glenn C. Telling; Michael Scott; James Mastrianni; Ruth Gabizon; Marilyn Torchia; Fred E. Cohen; Stephen J. DeArmond

1995-01-01

288

A bipolar functionality of Q/N-rich proteins: Lsm4 amyloid causes clearance of yeast prions.  

PubMed

Prions are epigenetic modifiers that cause partially loss-of-function phenotypes of the proteins in Saccharomyces cerevisiae. The molecular chaperone network that supports prion propagation in the cell has seen a great progress in the last decade. However, the cellular machinery to activate or deactivate the prion states remains an enigma, largely due to insufficient knowledge of prion-regulating factors. Here, we report that overexpression of a [PSI(+) ]-inducible Q/N-rich protein, Lsm4, eliminates the three major prions [PSI(+) ], [URE3], and [RNQ(+) ]. Subcloning analysis revealed that the Q/N-rich region of Lsm4 is responsible for the prion loss. Lsm4 formed an amyloid in vivo, which seemed to play a crucial role in the prion elimination. Fluorescence correlation spectroscopy analysis revealed that in the course of the Lsm4-driven [PSI(+) ] elimination, the [PSI(+) ] aggregates undergo a size increase, which ultimately results in the formation of conspicuous foci in otherwise [psi(-) ]-like mother cells. We also found that the antiprion activity is a general property of [PSI(+) ]-inducible factors. These data provoked a novel "unified" model that explains both prion induction and elimination by a single scheme. PMID:23512891

Oishi, Keita; Kurahashi, Hiroshi; Pack, Chan-Gi; Sako, Yasushi; Nakamura, Yoshikazu

2013-03-20

289

Antigenic characterization of an abnormal isoform of prion protein using a new diverse panel of monoclonal antibodies  

Microsoft Academic Search

We established a panel of monoclonal antibodies (mAbs) against prion protein (PrP) by immunizing PrP gene-ablated mice with the pathogenic isoform of prion protein (PrPSc) or recombinant prion protein (rPrP). The mAbs could be divided into at least 10 groups by fine epitope analyses using mutant rPrPs and pepspot analysis. Seven linear epitopes, lying within residues 56–90, 119–127, 137–143, 143–149,

Chan-Lan Kim; Atsushi Umetani; Toshio Matsui; Naotaka Ishiguro; Morikazu Shinagawa; Motohiro Horiuchi

2004-01-01

290

Oral treatment targeting the unfolded protein response prevents neurodegeneration and clinical disease in prion-infected mice.  

PubMed

During prion disease, an increase in misfolded prion protein (PrP) generated by prion replication leads to sustained overactivation of the branch of the unfolded protein response (UPR) that controls the initiation of protein synthesis. This results in persistent repression of translation, resulting in the loss of critical proteins that leads to synaptic failure and neuronal death. We have previously reported that localized genetic manipulation of this pathway rescues shutdown of translation and prevents neurodegeneration in a mouse model of prion disease, suggesting that pharmacological inhibition of this pathway might be of therapeutic benefit. We show that oral treatment with a specific inhibitor of the kinase PERK (protein kinase RNA-like endoplasmic reticulum kinase), a key mediator of this UPR pathway, prevented UPR-mediated translational repression and abrogated development of clinical prion disease in mice, with neuroprotection observed throughout the mouse brain. This was the case for animals treated both at the preclinical stage and also later in disease when behavioral signs had emerged. Critically, the compound acts downstream and independently of the primary pathogenic process of prion replication and is effective despite continuing accumulation of misfolded PrP. These data suggest that PERK, and other members of this pathway, may be new therapeutic targets for developing drugs against prion disease or other neurodegenerative diseases where the UPR has been implicated. PMID:24107777

Moreno, Julie A; Halliday, Mark; Molloy, Colin; Radford, Helois; Verity, Nicholas; Axten, Jeffrey M; Ortori, Catharine A; Willis, Anne E; Fischer, Peter M; Barrett, David A; Mallucci, Giovanna R

2013-10-01

291

Effect of the E200K Mutation on Prion Protein Metabolism  

PubMed Central

The hallmark of prion diseases is the cerebral accumulation of a conformationally altered isoform (PrPSc) of a normal cellular protein, the prion protein (PrPC). In the inherited form, mutations in the prion protein gene are thought to cause the disease by altering the metabolism of the mutant PrP (PrPM) engendering its conversion into PrPSc. We used a cell model to study biosynthesis and processing of PrPM carrying the glutamic acid to lysine substitution at residue 200 (E200K), which is linked to the most common inherited human prion disease. PrPM contained an aberrant glycan at residue 197 and generated an increased quantity of truncated fragments. In addition, PrPM showed impaired transport of the unglycosylated isoform to the cell surface. Similar changes were found in the PrP isolated from brains of patients affected by the E200K variant of Creutzfeldt-Jakob disease. Although the cellular PrPM displayed some characteristics of PrPSc, the PrPSc found in the E200K brains was quantitatively and qualitatively different. We propose that the E200K mutation cause the same metabolic changes of PrPM in the cell model and in the brain. However, in the brain, PrPM undergoes additional modifications, by an age-dependent mechanism that leads to the formation of PrPSc and the development of the disease.

Capellari, Sabina; Parchi, Piero; Russo, Claudio M.; Sanford, Jeremy; Sy, Man-Sun; Gambetti, Pierluigi; Petersen, Robert B.

2000-01-01

292

Development of techniques in magnetic resonance and structural studies of the prion protein  

SciTech Connect

Magnetic resonance is the most powerful analytical tool used by chemists today. Its applications range from determining structures of large biomolecules to imaging of human brains. Nevertheless, magnetic resonance remains a relatively young field, in which many techniques are currently being developed that have broad applications. In this dissertation, two new techniques are presented, one that enables the determination of torsion angles in solid-state peptides and proteins, and another that involves imaging of heterogenous materials at ultra-low magnetic fields. In addition, structural studies of the prion protein via solid-state NMR are described. More specifically, work is presented in which the dependence of chemical shifts on local molecular structure is used to predict chemical shift tensors in solid-state peptides with theoretical ab initio surfaces. These predictions are then used to determine the backbone dihedral angles in peptides. This method utilizes the theoretical chemicalshift tensors and experimentally determined chemical-shift anisotropies (CSAs) to predict the backbone and side chain torsion angles in alanine, leucine, and valine residues. Additionally, structural studies of prion protein fragments are described in which conformationally-dependent chemical-shift measurements were made to gain insight into the structural differences between the various conformational states of the prion protein. These studies are of biological and pathological interest since conformational changes in the prion protein are believed to cause prion diseases. Finally, an ultra-low field magnetic resonance imaging technique is described that enables imaging and characterization of heterogeneous and porous media. The notion of imaging gases at ultra-low fields would appear to be very difficult due to the prohibitively low polarization and spin densities as well as the low sensitivities of conventional Faraday coil detectors. However, Chapter 5 describes how gas imaging at ultra-low fields is realized by incorporating the high sensitivities of a dc superconducting quantum interference device (SQUID) with the high polarizations attainable through optica11y pumping {sup 129}Xe gas.

Bitter, Hans-Marcus L.

2000-07-01

293

Murine recombinant prion protein induces ordered aggregation of linear nucleic acids to condensed globular structures  

Microsoft Academic Search

Summary.  ?Interaction between nucleic acid and recombinant murine prion protein, MoPrPC resulted in a time-dependent change in the nucleic acid morphology revealed by electron microscopy. After the addition of\\u000a the protein to DNA, association of small number of nucleic acid molecules (nucleo-protein complex) was followed by aggregation\\u000a of large number of them still retaining their initial linear morphology. With increase in

P. K. Nandi; P.-Y. Sizaret

2001-01-01

294

Identification of cDNAs from Japanese pufferfish ( Fugu rubripes) and Atlantic salmon ( Salmo salar) coding for homologues to tetrapod prion proteins  

Microsoft Academic Search

We identified cDNAs coding for homologues to tetrapod prion proteins (PrPs) in Atlantic salmon (Salmo salar) and Japanese pufferfish (Fugu rubripes), which were termed ‘similar to PrPs’ (stPrPs). Besides significant sequence homologies the fish stPrPs display characteristic structural features in common with tetrapod PrPs. In addition, two stPrPs were shown to be highly expressed in brain tissue. None of the

Birgit Oidtmann; Dietrich Simon; Nikola Holtkamp; Rudolf Hoffmann; Michael Baier

2003-01-01

295

Examination of the human prion protein-like gene Doppel for genetic susceptibility to sporadic and variant Creutzfeldt–Jakob disease  

Microsoft Academic Search

A novel human gene named Doppel (DPL) that has homology to the prion protein gene (PRNP) has recently been identified on chromosome 20p. By automated sequencing we have found a common (M174T, 48%) and an uncommon coding polymorphism. The polymorphic frequency of the M174T allele was examined in cases of variant and sporadic Creutzfeldt–Jakob Disease and compared with the frequency

Simon Mead; Jonathan Beck; Andrew Dickinson; Elizabeth M. C Fisher; John Collinge

2000-01-01

296

Identification of Misfolded Proteins in Body Fluids for the Diagnosis of Prion Diseases  

PubMed Central

Transmissible spongiform encephalopathy (TSE) or prion diseases are fatal rare neurodegenerative disorders affecting man and animals and caused by a transmissible infectious agent. TSE diseases are characterized by spongiform brain lesions with neuronal loss and the abnormal deposition in the CNS, and to less extent in other tissues, of an insoluble and protease resistant form of the cellular prion protein (PrPC), named PrPTSE. In man, TSE diseases affect usually people over 60 years of age with no evident disease-associated risk factors. In some cases, however, TSE diseases are unequivocally linked to infectious episodes related to the use of prion-contaminated medicines, medical devices, or meat products as in the variant Creutzfeldt-Jakob disease (CJD). Clinical signs occur months or years after infection, and during this silent period PrPTSE, the only reliable marker of infection, is not easily measurable in blood or other accessible tissues or body fluids causing public health concerns. To overcome the limit of PrPTSE detection, several highly sensitive assays have been developed, but attempts to apply these techniques to blood of infected hosts have been unsuccessful or not yet validated. An update on the latest advances for the detection of misfolded prion protein in body fluids is provided.

Pocchiari, Maurizio

2013-01-01

297

Polar substitutions in helix 3 of the prion protein produce transmembrane isoforms that disturb vesicle trafficking.  

PubMed

Prion diseases encompass a diverse group of neurodegenerative conditions characterized by the accumulation of misfolded prion protein (PrP) isoforms. Other conformational variants of PrP have also been proposed to contribute to neurotoxicity in prion diseases, including misfolded intermediates as well as cytosolic and transmembrane isoforms. To better understand PrP neurotoxicity, we analyzed the role of two highly conserved methionines in helix 3 on PrP biogenesis, folding and pathogenesis. Expression of the PrP-M205S and -M205,212S mutants in Drosophila led to hyperglycosylation, intracellular accumulation and widespread conformational changes due to failure of oxidative folding. Surprisingly, PrP-M205S and -M205,212S acquired a transmembrane topology (Ctm) previously linked to mutations in the signal peptide (SP) and the transmembrane domain (TMD). PrP-M205,212S also disrupted the accumulation of key neurodevelopmental proteins in lipid rafts, resulting in shortened axonal projections. These results uncover a new role for the hydrophobic domain in promoting oxidative folding and preventing the formation of neurotoxic Ctm PrP, mechanisms that may be relevant in the pathogenesis of both inherited and sporadic prion diseases. PMID:23771030

Sanchez-Garcia, Jonatan; Arbelaez, Daniela; Jensen, Kurt; Rincon-Limas, Diego E; Fernandez-Funez, Pedro

2013-06-13

298

Lentivector-mediated RNAi efficiently suppresses prion protein and prolongs survival of scrapie-infected mice  

PubMed Central

Prion diseases are fatal neurodegenerative diseases characterized by the accumulation of PrPSc, the infectious and protease-resistant form of the cellular prion protein (PrPC). We generated lentivectors expressing PrPC-specific short hairpin RNAs (shRNAs) that efficiently silenced expression of the prion protein gene (Prnp) in primary neuronal cells. Treatment of scrapie-infected neuronal cells with these lentivectors resulted in an efficient and stable suppression of PrPSc accumulation. After intracranial injection, lentiviral shRNA reduced PrPC expression in transgenic mice carrying multiple copies of Prnp. To test the therapeutic potential of lentiviral shRNA, we used what we believe to be a novel approach in which the clinical situation was mimicked. We generated chimeric mice derived from lentivector-transduced embryonic stem cells. Depending on the degree of chimerism, these animals carried the lentiviral shRNAs in a certain percentage of brain cells and expressed reduced levels of PrPC. Importantly, in highly chimeric mice, survival after scrapie infection was significantly extended. Taken together, these data suggest that lentivector-mediated RNA interference could be an approach for the treatment of prion disease.

Pfeifer, Alexander; Eigenbrod, Sabina; Al-Khadra, Saba; Hofmann, Andreas; Mitteregger, Gerda; Moser, Markus; Bertsch, Uwe; Kretzschmar, Hans

2006-01-01

299

Two amyloid states of the prion protein display significantly different folding patterns  

PubMed Central

Summary It has been well established that a single amino acid sequence can give rise to several conformationally distinct amyloid states. The extent to which amyloid structures formed within the same sequence are different, however, remains unclear. To address this question we studied two amyloid states (referred to as R- and S-fibrils) produced in vitro from highly purified full-length recombinant prion protein (PrP). Several biophysical techniques including X-ray diffraction, CD, FTIR, hydrogen-deuterium exchange, proteinase K-digestion, and binding of a conformation-sensitive fluorescence dye revealed that R- and S-fibrils have substantially different secondary, tertiary and quaternary structures. While both states displayed a 4.8 Å meridional X-ray diffraction typical for amyloid cross-? spines, they showed markedly different equatorial profiles suggesting different folding pattern of ?-strands. The experiments on hydrogen-deuterium exchange monitored by FTIR revealed that only small fractions of amide protons were protected in R- or S-fibrils, an argument for the dynamic nature of their cross-? structure. Despite this fact, both amyloid states were found to be very stable conformationally as judged from temperature-induced denaturation monitored by FTIR and the conformation-sensitive dye. Upon heating to 80 °C, only local unfolding was revealed, while individual state-specific cross-? features were preserved. The current studies demonstrated that the two amyloid states formed by the same amino acid sequence exhibited significantly different folding patterns that presumably reflect two different architectures of cross-? structure. Both S- and R-fibrils, however, shared high conformational stability arguing that the energy landscape for protein folding and aggregation can contain several deep free energy minima.

Ostapchenko, Valeriy G.; Sawaya, Michael R.; Makarava, Natallia; Savtchenko, Regina; Nilsson, K. Peter R.; Eisenberg, David; Baskakov, Ilia V.

2010-01-01

300

IDENTIFICATION AND REMOVAL OF PROTEINS THAT CO-PURIFY WITH INFECTIOUS PRION PROTEIN IMPROVES THE ANALYSIS OF ITS SECONDARY STRUCTURE  

PubMed Central

Prion diseases are neurodegenerative disorders associated with the accumulation of an abnormal isoform of the mammalian prion protein (PrP). Fourier transform infrared spectroscopy (FTIR) has previously been used to show that the conformation of aggregated, infectious PrP (PrPSc) varies between prion strains and these unique conformations may determine strain-specific disease phenotypes. However, the relative amounts of ?-helix, ?-sheet and other secondary structures have not always been consistent between studies suggesting that other proteins might be confounding the analysis of PrPSc secondary structure. We have used FTIR and tandem mass spectrometry to analyze enriched PrPSc from mouse and hamster prion strains both before and after the removal of protein contaminants that commonly co-purify with PrPSc. Our data show that non-PrP proteins do contribute to absorbances that have been associated with ?-helical, loop, turn, and ?-sheet structures attributed to PrPSc. The major contaminant, the ?-helical protein ferritin, absorbs strongly at 1652cm?1 in the FTIR spectrum associated with PrPSc. However, even the removal of greater than 99% of the ferritin from PrPSc did not completely abolish absorbance at 1652cm?1. Our results show that contaminating proteins alter the FTIR spectrum attributed to PrPSc and suggest that the ?-helical, loop/turn, and ?-sheet secondary structure that remains following their removal are derived from PrPSc itself.

Moore, Roger A.; Timmes, Andrew; Wilmarth, Phillip A.; Safronetz, David; Priola, Suzette A.

2013-01-01

301

Molecular interaction between prion protein and GFAP both in native and recombinant forms in vitro  

Microsoft Academic Search

Gliosis of glial fibrillary acidic protein (GFAP) associated astrocytes is considered to be one of the hallmarks of transmissible\\u000a spongiform encephalopathies (TSEs). In the present study, remarkable GFAP–PrPSc or GFAP–PrPC complexes were separately detected in the brain homogenates of 263 K (Scrapie)-infected or normal hamsters by co-immunoprecipitation\\u000a assay. To get more exact molecular evidences for interaction between prion protein (PrP) and

Chen-Fang Dong; Xiao-Fan Wang; Xin Wang; Song Shi; Gui-Rong Wang; Bing Shan; Run An; Xiao-Li Li; Bao-Yun Zhang; Jun Han; Xiao-Ping Dong

2008-01-01

302

Synthesis and structural characterization of a mimetic membrane-anchored prion protein  

Microsoft Academic Search

During pathogenesis of transmissible spongiform encephalopathies (TSEs) an abnormal form (PrPSc) of the host encoded prion protein (PrPC) accu- mulates in insoluble fibrils and plaques. The two forms of PrP appear to have identical covalent structures, but differ in secondary and tertiary structure. Both PrPC and PrPSc have glycosylphospatidylinositol (GPI) anchors through which the protein is tethered to cell membranes.

Matthew R. Hicks; Andrew C. Gill; Imanpreet K. Bath; Atvinder K. Rullay; Ian D. Sylvester; David H. Crout; Teresa J. T. Pinheiro

2006-01-01

303

Flexibility of the murine prion protein and its Asp178Asn mutant investigated by molecular dynamics simulations  

Microsoft Academic Search

Inherited forms of transmissible spongiform encephalopathy, e.g. familial Creutzfeldt–Jakob disease, Gerstmann–Sträussler–Scheinker syndrome and fatal familial insomnia, segregate with specific point mutations of the prion protein. It has been proposed that the pathologically relevant Asp178Asn (D178N) mutation might destabilize the structure of the prion protein because of the loss of the Arg164–Asp178 salt bridge. Molecular dynamics simulations of the structured C-terminal

Jörg Gsponer; Philippe Ferrara; Amedeo Caflisch

2001-01-01

304

Increased expression of prion protein is associated with changes in dopamine metabolism and MAO activity in PC12 cells  

Microsoft Academic Search

Prion diseases of humans and animals occur following infection with infectious agents containing PrPSc or in situations in which there is a mutation of the prior protein (PrP) gene. The cellular prion protein (PrPC) is a sialoglycoprotein that is expressed predominantly in neurons. PrPC is converted into a pathogenic form of PrP (PrPSc), which is distinguishable from PrPC by its

Hyoung-Gon Lee; Seok-Joo Park; Eun-Kyoung Choi; Richard I. Carp; Yong-Sun Kim

1999-01-01

305

Different Patterns of Truncated Prion Protein Fragments Correlate with Distinct Phenotypes in P102L Gerstmann--Straussler--Scheinker Disease  

Microsoft Academic Search

The clinicopathological phenotype of the Gerstmann--Straussler--Scheinker disease (GSS) variant linked to the codon 102 mutation in the prion protein (PrP) gene (GSS P102L) shows a high heterogeneity. This variability also is observed in subjects with the same prion protein gene PRNP haplotype and is independent from the duration of the disease. Immunoblot analysis of brain homogenates from GSS P102L patients

Piero Parchi; Shu G. Chen; Paul Brown; Wenquan Zou; Sabina Capellari; Herbert Budka; Johannes Hainfellner; Patricio F. Reyes; Gregory T. Golden; Jean J. Hauw; D. Carleton Gajdusek; Pierluigi Gambetti

1998-01-01

306

Spongiform Pathology in Mouse CNS Lacking 'Neuropathy Target Esterase' and Cellular Prion Protein  

PubMed Central

Conditional inactivation of the ‘neuropathy target esterase’ (NTE) gene in mouse nerve cells was previously shown to result in CNS pathology comparable to the spongiform encephalopathy characteristic of prion diseases. To determine whether cellular prion protein (PrPc) is essential for development of this pathology we examined hippocampi of mice lacking NTE alone, PrPc alone or both NTE and PrPc. Light microscopic survey showed clear-cut spongiform changes in a majority of NTE-/- and NTE/PrP-/- double knockout mice but in only one PrP-/- mouse. EM analysis of spongiform lesions from NTE-/- and NTE/PrP-/- mice, and from the one affected PrP-/- mouse, revealed patches of branching tubular inclusions, comparable to the ‘tubulovesicular inclusions’ described previously in prion diseases. We conclude that spongiform pathology in conditional NTE knockout mice is not mediated by PrPc, and that tubulovesicular inclusions can be seen in spongiform encephalopathy of other etiologies and are not pathognomonic of prion disease.

Rosenbluth, Jack; Schiff, Rolf; Lam, Pokman; Nuriel, Tal; Chao, Moses V.

2009-01-01

307

Melatonin-induced autophagy protects against human prion protein-mediated neurotoxicity.  

PubMed

  Melatonin has neuroprotective effects in the models of neurodegenerative disease including Alzheimer's and Parkinson's disease. Several studies have shown that melatonin prevents neurodegeneration by regulation of mitochondrial function. However, the protective action of melatonin has not been reported in prion disease. We investigated the influence of melatonin on prion-mediated neurotoxicity. Melatonin rescued neuronal cells from PrP(106-126)-induced neurotoxicity by prevention of mitochondrial dysfunction. Moreover, the protective effect of melatonin against mitochondrial dysfunction was related with autophagy activation. Melatonin-treated cells were dose-dependently increased in LC3-II, an autophagy marker. Melatonin-induced autophagy prevented a PrP(106-126)-induced reduction in mitochondrial potential and translocation of Bax to the mitochondria and cytochrome c release. On the other hand, downregulation of autophagy protein 5 with Atg5 siRNA or the autophagy blocker 3-methyladenine prevented the melatonin-mediated neuroprotective effects. This is the first report demonstrating that treatment with melatonin appears to protect against prion-mediated neurotoxicity and that the neuroprotection is induced by melatonin-mediated autophagy signals. The results of this study suggest that regulation of melatonin is a therapeutic strategy for prion peptide-induced apoptosis. PMID:22335252

Jeong, Jae-Kyo; Moon, Myung-Hee; Lee, You-Jin; Seol, Jae-Won; Park, Sang-Youel

2012-02-16

308

Reduced Translocation of Nascent Prion Protein During ER Stress Contributes to Neurodegeneration  

PubMed Central

Summary During acute stress in the endoplasmic reticulum (ER), mammalian prion protein (PrP) is temporarily prevented from translocation into the ER and instead routed directly for cytosolic degradation. This ‘pre-emptive’ quality control (pQC) system benefits cells by minimizing PrP aggregation in the secretory pathway during ER stress. However, the potential toxicity of cytosolic PrP raised the possibility that persistent pQC of PrP contributes to neurodegeneration in prion diseases. Here, we find evidence of ER stress and decreased translocation of nascent PrP during prion infection. Transgenic mice expressing a PrP variant with reduced translocation at levels expected during ER stress was sufficient to cause several mild age-dependent clinical and histological manifestations of PrP-mediated neurodegeneration. Thus, an ordinarily adaptive quality control pathway can be contextually detrimental over long time periods. We propose that one mechanism of prion-mediated neurodegeneration involves an indirect ER stress-dependent effect on nascent PrP biosynthesis and metabolism.

Rane, Neena S.; Kang, Sang-Wook; Chakrabarti, Oishee; Feigenbaum, Lionel; Hegde, Ramanujan S.

2008-01-01

309

Unique structural properties associated with mouse prion ?105-125 protein  

PubMed Central

Murine prion protein deleted for residues 105–125 is intrinsically neurotoxic and mediates a TSE-like phenotype in transgenic mice. Equivalent and overlapping deletions were expressed in E.coli, purified and analyzed. Among mutants spanning the region 95–135, a construct lacking solely residues 105–125 had distinct properties when compared with the full-length prion protein 23–231 or other deletions. This distinction was also apparent followed expression in eukaryotic cells. Unlike the full-length protein, all deletion mutants failed to bind to synthetic membranes in vitro. These data suggest a novel structure for the 105–125 deleted variant that may relate to its biological properties.

Patel, Avnish; Vasiljevic, Snezana; Jones, Ian M.

2013-01-01

310

Genetic variability of the coding region for the prion protein gene (PRNP) in gayal (Bos frontalis).  

PubMed

The gayal (Bos frontalis) is a rare semi-wild bovid species in which bovine spongiform encephalopathy (BSE) has not been reported. Polymorphisms of the prion protein gene (PRNP) have been correlated significantly with resistance to BSE. In this study, the coding region of PRNP was cloned and characterized in samples from 125 gayal. A total of ten single nucleotide polymorphisms (SNPs), including six silent mutations (C60T, G75A, A108T, G126A, C357T and C678T) and four mis-sense mutations (C8A, G145A, G461A and C756G), corresponding to amino acids T3K, G49S9, N154S and I252M were identified, revealing high genetic diversity. Three novel SNPs including C60T, G145A and C756G, which have not been reported previously in bovid species, were retrieved. There also was one insertion-deletion (187Del24) at the N-terminal octapeptide repeat region. Alignment of nucleotide and amino acid sequences showed a high degree of similarity with other bovid species. Using phylogenetic analyses it was revealed that gayal has a close genetic relationship with Zebu cattle. In short, preliminary information is provided about genotypes of the PRNP in gayal. This could assist with the study of the pathogenesis of transmissible spongiform encephalopathies and cross species transmission as well as a molecular breeding project for gayal in China. PMID:21633886

Xi, Dongmei; Liu, Qing; Guo, Jianhong; Yu, Hongman; Yang, Yuai; He, Yiduo; Mao, Huaming; Gou, Xiao; Deng, Weidong

2011-06-03

311

The prion protein gene in humans revisited: Lessons from a worldwide resequencing study  

PubMed Central

Ample evidence has accumulated showing that different coding variants of the PRNP gene confer differential susceptibility for prion diseases. Here we evaluate the patterns of nucleotide variation in PRNP exon 2, which includes all the protein-coding sequence, by resequencing a worldwide sample of 174 humans for 2378 bp. In line with previous studies, we found two main haplotypes differentiated by nonsynonymous substitution in codon 129. Our analyses reveal the worldwide pattern of variation at the PRNP gene to be inconsistent with neutral expectations, indicating instead an excess of low-frequency variants, a footprint of the action of either positive or purifying selection. A comparison of neutrality test statistics for PRNP with other human genes indicates that the signal of positive selection on PRNP is stronger than expected from a possible confounding genome-wide background signal of population expansion. Two main conclusions arise from our analysis. First, the existence of an ancient, stable, balanced polymorphism that has been claimed in a previous study and related to cannibalism can be rejected and is shown to be due to ascertainment bias. Second, our results are consistent with a complex history of selection including mainly positive selection, even if short local periods of balancing selection (Kuru-like episodes), or even a weak purifying selection model, are consistent with our data.

Soldevila, Marta; Andres, Aida M.; Ramirez-Soriano, Anna; Marques-Bonet, Tomas; Calafell, Francesc; Navarro, Arcadi; Bertranpetit, Jaume

2006-01-01

312

Prion Protein Expression and Processing in Human Mononuclear Cells: The Impact of the Codon 129 Prion Gene Polymorphism  

Microsoft Academic Search

BackgroundSo far, all clinical cases of new variant Creutzfeldt-Jakob disease (vCJD), thought to result from the Bovine Spongiform Encephalopathy (BSE) prion agent, have shown Methionine–Methionine (M\\/M) homozygosity at the M129V polymorphism of the PRNP gene. Although established, this relationship is still not understood. In both vCJD and experimental BSE models prion agents do reach the bloodstream, raising concerns regarding disease

Christiane Segarra; Sylvain Lehmann; Joliette Coste; Adam J. Ratner

2009-01-01

313

Attempts to convert the cellular prion protein into the scrapie isoform in cell-free systems.  

PubMed Central

The scrapie prion protein (PrPSc) is derived from a cellular isoform (PrPC) that acquires protease resistance posttranslationally. We have used several different experimental approaches in attempts to reconstitute in vitro the processes leading to protease-resistant PrPSc molecules. In the first study, we performed mixing experiments by adding mouse PrP 27-30 (MoPrP27-30), the protease-resistant core of PrPSc, to PrPC and then incubating the mixture to investigate the possibility of heterodimer formation as a first step in prion replication. We used epitopically tagged PrP molecules, synthesized in murine neuroblastoma (N2a) cells transfected with the chimeric mouse/Syrian hamster MHM2 PrP construct, which are recognized by the Syrian hamster-specific monoclonal antibody 3F4. After as long as 24 h of incubation, the reaction mixture was assayed for heterodimeric intermediates of MHM2 PrPC and MoPrPSc and for protease-resistant 3F4-reactive PrP. We were unable to identify any aggregates of MHM2 PrPC and MoPrPSc on immunoblots; furthermore, we did not observe de novo formation of protease-resistant MHM2 PrP. In a second study, MoPrPC was metabolically radiolabeled in scrapie prion-infected N2a cultured cells, and then the cell extract was homogenized and incubated under various conditions to allow for the formation of protease-resistant MoPrPSc. We observed no radiolabeled MoPrPSc by immunoprecipitation after as long as 24 h of in vitro incubation. In a third approach, Syrian hamster PrP (SHaPrP) was synthesized in a cell-free translation system supplemented with microsomal membranes derived from either normal or scrapie prion-infected cultured cells. We found that all SHaPrP species translocated across microsomal membranes from scrapie prion-infected cells were protease sensitive in the presence of detergents and displayed the same topology as those generated by microsomes from normal cells or from dog pancreas. We also studied PrP molecules that encode the codon 102 mutation that causes the rare human prion disease Gerstmann-Sträussler-Scheinker (GSS) syndrome. On the basis of our data, GSSPrP appears to yield topological forms similar to those of the wild-type PrP when processed by either normal or scrapie prion-derived microsomes. Images

Raeber, A J; Borchelt, D R; Scott, M; Prusiner, S B

1992-01-01

314

Modulation of Proteinase K-resistant Prion Protein in Cells and Infectious Brain Homogenate by Redox Iron: Implications for Prion Replication and Disease Pathogenesis  

PubMed Central

The principal infectious and pathogenic agent in all prion disorders is a ?-sheet–rich isoform of the cellular prion protein (PrPC) termed PrP-scrapie (PrPSc). Once initiated, PrPSc is self-replicating and toxic to neuronal cells, but the underlying mechanisms remain unclear. In this report, we demonstrate that PrPC binds iron and transforms to a PrPSc-like form (*PrPSc) when human neuroblastoma cells are exposed to an inorganic source of redox iron. The *PrPSc thus generated is itself redox active, and it induces the transformation of additional PrPC, simulating *PrPSc propagation in the absence of brain-derived PrPSc. Moreover, limited depletion of iron from prion disease-affected human and mouse brain homogenates and scrapie-infected mouse neuroblastoma cells results in 4- to 10-fold reduction in proteinase K (PK)-resistant PrPSc, implicating redox iron in the generation, propagation, and stability of PK-resistant PrPSc. Furthermore, we demonstrate increased redox-active ferrous iron levels in prion disease-affected brains, suggesting that accumulation of PrPSc is modulated by the combined effect of imbalance in brain iron homeostasis and the redox-active nature of PrPSc. These data provide information on the mechanism of replication and toxicity by PrPSc, and they evoke predictable and therapeutically amenable ways of modulating PrPSc load.

Basu, Subhabrata; Mohan, Maradumane L.; Luo, Xiu; Kundu, Bishwajit; Kong, Qingzhong

2007-01-01

315

The POM Monoclonals: A Comprehensive Set of Antibodies to Non-Overlapping Prion Protein Epitopes  

PubMed Central

PrPSc, a misfolded and aggregated form of the cellular prion protein PrPC, is the only defined constituent of the transmissible agent causing prion diseases. Expression of PrPC in the host organism is necessary for prion replication and for prion neurotoxicity. Understanding prion diseases necessitates detailed structural insights into PrPC and PrPSc. Towards this goal, we have developed a comprehensive collection of monoclonal antibodies denoted POM1 to POM19 and directed against many different epitopes of mouse PrPC. Three epitopes are located within the N-terminal octarepeat region, one is situated within the central unstructured region, and four epitopes are discontinuous within the globular C-proximal domain of PrPC. Some of these antibodies recognize epitopes that are resilient to protease digestion in PrPSc. Other antibodies immunoprecipitate PrPC, but not PrPSc. A third group was found to immunoprecipitate both PrP isoforms. Some of the latter antibodies could be blocked with epitope-mimicking peptides, and incubation with an excess of these peptides allowed for immunochromatography of PrPC and PrPSc. Amino-proximal antibodies were found to react with repetitive PrPC epitopes, thereby vastly increasing their avidity. We have also created functional single-chain miniantibodies from selected POMs, which retained the binding characteristics despite their low molecular mass. The POM collection, thus, represents a unique set of reagents allowing for studies with a variety of techniques, including western blotting, ELISA, immunoprecipitation, conformation-dependent immunoassays, and plasmon surface plasmon resonance-based assays.

Polymenidou, Magdalini; Moos, Rita; Scott, Mike; Sigurdson, Christina; Shi, Yong-zhong; Yajima, Bill; Hafner-Bratkovic, Iva; Jerala, Roman; Hornemann, Simone; Wuthrich, Kurt; Bellon, Anne; Vey, Martin; Garen, Graciela; James, Michael N. G.; Kav, Nat; Aguzzi, Adriano

2008-01-01

316

Absolute quantification of prion protein (90-231) using stable isotope-labeled chymotryptic peptide standards in a LC-MRM AQUA workflow  

PubMed Central

Substantial evidence indicates that the disease-associated conformer of the prion protein (PrPTSE) constitutes the etiological agent in prion diseases. These diseases affect multiple mammalian species. PrPTSE has the ability to convert the conformation of the normal prion protein (PrPC) into a ?-sheet rich form resistant to proteinase K digestion. Common immunological techniques lack the sensitivity to detect PrPTSE at sub-femtomole levels while animal bioassays, cell culture, and in vitro conversion assays offer ultrasensitivity but lack the high-throughput the immunological assays offer. Mass spectrometry is an attractive alternative to the above assays as it offers high-throughput, direct measurement of a protein’s signature peptide, often with sub-femtomole sensitivities. Although a liquid chromatography-multiple reaction monitoring (LC-MRM) method has been reported for PrPTSE, the chemical composition and lack of amino acid sequence conservation of the signature peptide may compromise its accuracy and make it difficult to apply to multiple species. Here, we demonstrate that an alternative protease (chymotrypsin) can produce signature peptides suitable for a LC-MRM absolute quantification (AQUA) experiment. The new method offers several advantages, including: (1) a chymotryptic signature peptide lacking chemically active residues (Cys, Met) that can confound assay accuracy; (2) low attomole limits of detection and quantitation (LOD and LOQ); and (3) a signature peptide retaining the same amino acid sequence across most mammals naturally susceptible to prion infection as well as important laboratory models. To the authors’ knowledge, this is the first report of the use of a non-tryptic peptide in a LC-MRM AQUA workflow.

Sturm, Robert; Kreitinger, Gloria; Booth, Clarissa; Smith, Lloyd; Pedersen, Joel; Li, Lingjun

2012-01-01

317

Immunization with Recombinant Prion Protein Leads to Partial Protection in a Murine Model of TSEs through a Novel Mechanism  

PubMed Central

Transmissible spongiform encephalopathies are neurodegenerative diseases, which despite fervent research remain incurable. Immunization approaches have shown great potential at providing protection, however tolerance effects hamper active immunization protocols. In this study we evaluated the antigenic potential of various forms of recombinant murine prion protein and estimated their protective efficacy in a mouse model of prion diseases. One of the forms tested provided a significant elongation of survival interval. The elongation was mediated via an acute depletion of mature follicular dendritic cells, which are associated with propagation of the prion infectious agent in the periphery and in part to the development of humoral immunity against prion protein. This unprecedented result could offer new strategies for protection against transmissible encephalopathies as well as other diseases associated with follicular dendritic cells.

Xanthopoulos, Konstantinos; Lagoudaki, Rosa; Kontana, Anastasia; Kyratsous, Christos; Panagiotidis, Christos; Grigoriadis, Nikolaos; Yiangou, Minas; Sklaviadis, Theodoros

2013-01-01

318

Mixed Monte Carlo/Molecular Dynamics simulations of the prion protein.  

PubMed

In this paper we present the results of mixed Monte Carlo/Molecular Dynamics (MC/MD) simulations of the D178N mutant of the human prion protein. We have used the MC moves for polypeptide sampling known as Concerted Rotations with Angles (CRA) to selectively sample the region of the prion protein comprising the ?-sheet and one of the ?-helices. The results indicate that the MC/MD simulations sample the phase space substantially faster than regular Molecular Dynamics simulations starting with the same initial conditions. This work further indicates the MC/MD technique as a potentially powerful simulation tool, allowing the selective sampling of a region of a physical system that is deemed important. PMID:23501158

Ribeiro, Andre A S T; de Alencastro, Ricardo B

2013-02-26

319

Prion formation by a yeast GLFG nucleoporin  

PubMed Central

The self-assembly of proteins into higher order structures is both central to normal biology and a dominant force in disease. Certain glutamine/asparagine (Q/N)-rich proteins in the budding yeast Saccharomyces cerevisiae assemble into self-replicating amyloid-like protein polymers, or prions, that act as genetic elements in an entirely protein-based system of inheritance. The nuclear pore complex (NPC) contains multiple Q/N-rich proteins whose self-assembly has also been proposed to underlie structural and functional properties of the NPC. Here we show that an essential sequence feature of these proteins—repeating GLFG motifs—strongly promotes their self-assembly into amyloids with characteristics of prions. Furthermore, we demonstrate that Nup100 can form bona fide prions, thus establishing a previously undiscovered ability of yeast GLFG nucleoporins to adopt this conformational state in vivo.

Halfmann, Randal; Wright, Jessica R.; Alberti, Simon; Lindquist, Susan; Rexach, Michael

2012-01-01

320

FTY720 protects neuronal cells from damage induced by human prion protein by inactivating the JNK pathway.  

PubMed

Prion diseases affect the central nervous system (CNS) in humans and animals, and are associated with the conversion of the cellular prion protein (PrPC) to the misfolded isoform (PrPSc). FTY720, an immune modulator and synthetic analogue of sphingosine-1-phosphate (S1P), activates S1P receptors and has been shown to be effective in experimental models of transplantation and autoimmunity, including multiple sclerosis. Whereas the immune modulatory functions of FTY720 have been extensively investigated, the other functions of FTY720 are not yet well understood. In this study, we investigated the effects of FTY720 phosphate (FTY720-p) on prion protein-mediated neuronal cell death, as well as its effects on intracellular apoptotic pathways. Treatment with FTY720-p protected neuronal cells from synthetic human prion protein peptide [PrP (106?126)]-mediated damage and prevented mitochondrial dysfunction by inhibiting the activation of c-jun N-terminal kinase. Moreover, FTY720-p prevented the PrP (106?126)-induced reduction in mitochondrial potential, the translocation of Bax to the mitochondria and the release of cytochrome c. To the best of our knowledge, this study is the first to demonstrate the effects of FTY720 on prion protein-mediated neurotoxicity and to suggest that FTY720 has therapeutic potential in prion diseases. PMID:24142108

Moon, Myung-Hee; Jeong, Jae-Kyo; Lee, You-Jin; Park, Sang-Youel

2013-10-16

321

Spongiform encephalopathy in siblings with no evidence of protease-resistant prion protein or a mutation in the prion protein gene.  

PubMed

We discuss relevant aspects in two siblings with a neurodegenerative process of unclear aetiology who developed progressive dementia with global aphasia and hyperoral behaviour at the ages of 39 and 46 years and who died 6 and 5 years after disease onset. The cases were reported to the National Reference Center for TSE Surveillance in Göttingen, Germany. Detailed clinical examinations, CSF, blood samples, and copies of the important diagnostic tests (magnetic resonance imaging, electroencephalogram, laboratory tests) were obtained. Further neuropathological and genetic analyses were performed. Cerebral magnetic resonance imaging of both siblings showed prominent changes in signal intensity, especially in the left medial temporal cortex, but also the hippocampal formation. Neuropathological examination revealed spongiform changes, neuronal loss, and astrocytic gliosis, which are typical in Creutzfeldt-Jakob disease. However, no prion protein deposits were detectable by immunohistochemical analysis, Western blot, or PET blot, though abundant tau protein deposits were observed. A mutation in the coding region of the prion protein genes of both siblings was excluded. A detailed search of the literature revealed no other cases with a similar clinical and neuropathological appearance. While the disease aetiology remains unclear, the findings point to a neurodegenerative process and most likely a genetic disease. PMID:23546304

Varges, Daniela; Schulz-Schaeffer, Walter J; Wemheuer, Wiebke M; Damman, Insa; Schmitz, Matthias; Cramm, Maria; Kallenberg, Kai; Shirneshan, Katayoon; Elkenani, Manar; Markwort, Susanne; Faist, Michael; Kohlhase, Jürgen; Windl, Otto; Zerr, Inga

2013-04-02

322

Contributions of neuronal prion protein on sleep recovery and stress response following sleep deprivation  

Microsoft Academic Search

In order to gain insights on the function of the cellular prion protein (PrPC) sleep and the levels of the stress hormones corticosterone (CORT) and the adrenocorticotropic hormone (ACTH) before and after sleep deprivation (SD) were compared in two wild type (WT) mice strains and the following three PrPC transgenic lines: mice null for PrPC (mPrP0\\/0) and mice with specific

Manuel Sánchez-Alavez; Bruno Conti; Gianluca Moroncini; José R. Criado

2007-01-01

323

Cotranslational Partitioning of Nascent Prion Protein into Multiple Populations at the Translocation Channel  

Microsoft Academic Search

The decisive events that direct a single polypeptide such as the prion protein (PrP) to be synthesized at the endoplasmic reticulum in both fully translocated and transmembrane forms are poorly understood. In this study, we demonstrate that the topological heterogeneity of PrP is determined cotranslationally, while at the translocation channel. By evaluating sequential inter- mediates during PrP topogenesis, we find

Soo Jung Kim; Ramanujan S. Hegde

2002-01-01

324

Is There a Role for Cellular Prion Protein in Intrathymic T Cell Differentiation and Migration?  

Microsoft Academic Search

The cellular prion protein (PrPC) is expressed in the nervous and immune systems. Functionally, PrPC has been suggested to participate in neuron survival, neuritogenesis and T lymphocyte activation. Moreover, PrPC interaction with laminin influences neuronal adhesion and neurite extension. Nevertheless, so far the physiological role of PrPC has not been completely elucidated, particularly in the immune system. The aim of

Eugênia Terra-Granado; Luiz Ricardo Berbert; Juliana de Meis; Regina Nomizo; Vilma Regina Martins; Wilson Savino; Suse Dayse Silva-Barbosa

2007-01-01

325

Degradation of the Disease-Associated Prion Protein by a Serine Protease from Lichens  

Microsoft Academic Search

The disease-associated prion protein (PrPTSE), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrPTSE inactivation by lichens and

Christopher J. Johnson; James P. Bennett; Steven M. Biro; Juan Camilo Duque-Velasquez; Cynthia M. Rodriguez; Richard A. Bessen; Tonie E. Rocke; Jason C. Bartz

2011-01-01

326

Dissociation of prion protein amyloid seeding from transmission of a spongiform encephalopathy.  

PubMed

Misfolding and aggregation of proteins are common pathogenic mechanisms of a group of diseases called proteinopathies. The formation and spread of proteinaceous lesions within and between individuals were first described in prion diseases and proposed as the basis of their infectious nature. Recently, a similar "prion-like" mechanism of transmission has been proposed in other neurodegenerative diseases such as Alzheimer's disease. We investigated if misfolding and aggregation of corrupted prion protein (PrP(TSE)) are always associated with horizontal transmission of disease. Knock-in transgenic mice (101LL) expressing mutant PrP (PrP-101L) that are susceptible to disease but do not develop any spontaneous neurological phenotype were inoculated with (i) brain extracts containing PrP(TSE) from healthy 101LL mice with PrP plaques in the corpus callosum or (ii) brain extracts from mice overexpressing PrP-101L with neurological disease, severe spongiform encephalopathy, and formation of proteinase K-resistant PrP(TSE). In all instances, 101LL mice developed PrP plaques in the area of inoculation and vicinity in the absence of clinical disease or spongiform degeneration of the brain. Importantly, 101LL mice did not transmit disease on serial passage, ruling out the presence of subclinical infection. Thus, in both experimental models the formation of PrP(TSE) is not infectious. These results have implications for the interpretation of tests based on the detection of protein aggregates and suggest that de novo formation of PrP(TSE) in the host does not always result in a transmissible prion disease. In addition, these results question the validity of assuming that all diseases due to protein misfolding can be transmitted between individuals. PMID:24027305

Piccardo, Pedro; King, Declan; Telling, Glenn; Manson, Jean C; Barron, Rona M

2013-09-11

327

Solution Structure and Dynamics of the I214V Mutant of the Rabbit Prion Protein  

Microsoft Academic Search

BackgroundThe conformational conversion of the host-derived cellular prion protein (PrPC) into the disease-associated scrapie isoform (PrPSc) is responsible for the pathogenesis of transmissible spongiform encephalopathies (TSEs). Various single-point mutations in PrPCs could cause structural changes and thereby distinctly influence the conformational conversion. Elucidation of the differences between the wild-type rabbit PrPC (RaPrPC) and various mutants would be of great help

Yi Wen; Jun Li; Minqian Xiong; Yu Peng; Wenming Yao; Jing Hong; Donghai Lin

2010-01-01

328

Disease associated prion protein may deposit in the peripheral nervous system in human transmissible spongiform encephalopathies  

Microsoft Academic Search

There is increasing evidence indicating involvement of the peripheral nervous system (PNS) in the pathogenesis of transmissible\\u000a spongiform encephalopathies (TSEs). Immunocytochemically detectable deposits of TSE-specific abnormal prion protein (PrPsc) are considered as a surrogate marker for infectivity. We used anti-PrP immunocytochemistry to trace PrPsc deposition in spinal and enteric ganglia, and peripheral nerve in Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker\\u000a disease (GSS),

Johannes A. Hainfellner; Herbert Budka

1999-01-01

329

Genetic variability of the coding region for the prion protein gene ( PRNP ) in gayal ( Bos frontalis )  

Microsoft Academic Search

The gayal (Bos frontalis) is a rare semi-wild bovid species in which bovine spongiform encephalopathy (BSE) has not been reported. Polymorphisms of\\u000a the prion protein gene (PRNP) have been correlated significantly with resistance to BSE. In this study, the coding region of PRNP was cloned and characterized in samples from 125 gayal. A total of ten single nucleotide polymorphisms (SNPs),

Dongmei XiQing; Qing Liu; Jianhong Guo; Hongman Yu; Yuai Yang; Yiduo He; Huaming Mao; Xiao Gou; Weidong Deng

330

Scrapie-associated Prion Protein in the Gastro-intestinal Tract of Sheep with Natural Scrapie  

Microsoft Academic Search

The scrapie-associated prion protein (PrPSc), which is closely associated with scrapie infectivity, accumulates in the brain and lymphoid tissues of sheep with natural scrapie. The most probable portal of entry of the scrapie agent in sheep is the alimentary tract; little attention, however, has been paid to the gastro-intestinal tract in scrapie research. In this study, we examined the presence

L. J. M. van Keulen; B. E. C. Schreuder; M. E. W. Vromans; J. P. M. Langeveld; M. A. Smits

1999-01-01

331

Ultrasensitive detection of prion protein fibrils by flow cytometry in blood from cattle affected with bovine spongiform encephalopathy  

Microsoft Academic Search

BACKGROUND: The definite diagnosis of prion diseases such as Creutzfeldt-Jakob disease (CJD) in humans or bovine spongiform encephalopathy (BSE) in cattle currently relies on the post mortem detection of the pathological form of the prion protein (PrPSc) in brain tissue. Infectivity studies indicate that PrPSc may also be present in body fluids, even at presymptomatic stages of the disease, albeit

Lothar Trieschmann; Alexander Navarrete Santos; Katja Kaschig; Sandra Torkler; Elke Maas; Hermann Schätzl; Gerald Böhm

2005-01-01

332

Seeking for binding determinants of the prion protein to human plasminogen  

NASA Astrophysics Data System (ADS)

Plasminogen (Pg), a pro-protease implicated in neuronal excitotoxicity, has recently been identified as binding to prion protein (PrP) from several species. Although the precise effect of the binding of PrP to plasminogen in the course of prion-caused diseases has not yet been demonstrated, the implications of this important finding for diagnostic applications are straightforward. In this paper we have investigated the possible modes of interaction of PrP with plasminogen, by means of molecular modelling and computational simulation techniques. To this goal, we first exploited the information available for the mK2Pg/VEK-30 complex in order to identify the PrP residues which satisfy the specific electronic and geometric requirements needed to interact with the kringle lysine binding site, we compared the relevant mK2Pg/VEK-30 and mK2Pg/PrP interactions obtained from the simulated protein-protein complexes and we assessed the docking hypothesis utilized for the mK2Pg/PrP complex by simulating the interaction of PrP with the multi-kringle angiostatin, a more realistic model of the physiological target. The results obtained will be instrumental for planning experiments tailored to clarify the role of the plasminogen activator system in prion-related diseases and, eventually, for mimicking dominant binding determinants through structure-based drug design.

Menziani, M. C.; de Benedetti, P. G.; Langella, E.; Barone, V.

333

Insights into alternative prion protein topologies induced under high hydrostatic pressure  

NASA Astrophysics Data System (ADS)

The critical step in the pathogenesis of transmissible spongiform encephalopathies (TSEs) appears to be a conformational transition of a normal prion protein (PrPC) into a misfolded isoform (PrPSc). To gain insight into the structural conversion of the prion protein we have exploited the use of high hydrostatic pressure combined with various spectroscopic techniques. In vitro transitions of the recombinant PrP to a scrapie-like form have never resulted in an infectious structure. It is our hypothesis that the acquisition of the disease-causing conformation depends on folding pathways which are difficult to attain. We attempt to favour, via specific reaction conditions at high pressure, alternative routes of misfolding leading to a stable infectious amyloidogenic conformer. Our results have demonstrated the potential of high pressure to reveal various prion structural changes, which are inaccessible by conventional methods. Especially, we have characterized a pressure-induced conformer in which the normal agr-helical structure is changed into a highly aggregated bgr-sheet conformation showing markedly increased resistance to proteolysis (key markers of potential infectious agents). Our work may have important implications, not only for ultimately proving the protein-only hypothesis and for understanding the basic mechanism of the disease, but also for developing preventative and therapeutic measures.

Torrent, Joan; Alvarez-Martinez, Maria Teresa; Heitz, Frédéric; Liautard, Jean-Pierre; Balny, Claude; Lange, Reinhard

2004-04-01

334

The role of the cellular prion protein in the immune system  

PubMed Central

Prion protein (PrP) plays a key role in the pathogenesis of prion diseases. However, the normal function of the protein remains unclear. The cellular isoform (PrPC) is expressed widely in the immune system, in haematopoietic stem cells and mature lymphoid and myeloid compartments in addition to cells of the central nervous system. It is up-regulated in T cell activation and may be expressed at higher levels by specialized classes of lymphocyte. Furthermore, antibody cross-linking of surface PrP modulates T cell activation and leads to rearrangements of lipid raft constituents and increased phosphorylation of signalling proteins. These findings appear to indicate an important but, as yet, ill-defined role in T cell function. Although PrP–/– mice have been reported to have only minor alterations in immune function, recent work has suggested that PrP is required for self-renewal of haematopoietic stem cells. Here, we consider the evidence for a distinctive role for PrPC in the immune system and what the effects of anti-prion therapeutics may be on immune function.

Isaacs, J D; Jackson, G S; Altmann, D M

2006-01-01

335

Integrity of helix 2-helix 3 domain of the PrP protein is not mandatory for prion replication.  

PubMed

The process of prion conversion is not yet well understood at the molecular level. The regions critical for the conformational change of PrP remain mostly debated and the extent of sequence change acceptable for prion conversion is poorly documented. To achieve progress on these issues, we applied a reverse genetic approach using the Rov cell system. This allowed us to test the susceptibility of a number of insertion mutants to conversion into prion in the absence of wild-type PrP molecules. We were able to propagate several prions with 8 to 16 extra amino acids, including a polyglycine stretch and His or FLAG tags, inserted in the middle of the protease-resistant fragment. These results demonstrate the possibility to increase the length of the loop between helices H2 and H3 up to 4-fold, without preventing prion replication. They also indicate that this loop probably remains unstructured in PrP(Sc). We also showed that bona fide prions can be produced following insertion of octapeptides in the two C-terminal turns of H2. These insertions do not interfere with the overall fold of the H2-H3 domain indicating that the highly conserved sequence of the terminal part of H2 is not critical for the conversion. Altogether these data showed that the amplitude of modifications acceptable for prion conversion in the core of the globular domain of PrP is much greater than one might have assumed. These observations should help to refine structural models of PrP(Sc) and elucidate the conformational changes underlying prions generation. PMID:22511770

Salamat, Khalid; Moudjou, Mohammed; Chapuis, Jérôme; Herzog, Laetitia; Jaumain, Emilie; Béringue, Vincent; Rezaei, Human; Pastore, Annalisa; Laude, Hubert; Dron, Michel

2012-04-16

336

A novel three extra-repeat insertion in the prion protein gene (PRNP) in a patient with Creutzfeldt-Jakob disease  

Microsoft Academic Search

Sirs, Inherited prion diseases segregate with mutations in the coding region of the human prion protein gene (PRNP). Whilst particular point mutations in the central and C-terminal moiety of the prion protein (PrP) cause the majority of familial Creutzfeldt-Jakob disease (CJD), Gerstmann-Strussler-Scheinker syndrome, and fatal fa- milial insomnia, base pair insertions consisting of addi- tional copies of an octapeptide repeat,

E. Grasbon-Frodl; R. Schmalzbauer; P. Weber; B. Krebs; O. Windl; I. Zerr; H. A. Kretzschmar

2004-01-01

337

Intracellular accumulation of a 46 kDa species of mouse prion protein as a result of loss of glycosylation in cultured mammalian cells  

Microsoft Academic Search

Prion diseases are fatal neurodegenerative disorders characterized by the accumulation of an abnormal isoform (PrPSc) of the normal cellular prion protein (PrPC) in the brain. Reportedly, abnormal N-linked glycosylation patterns in PrPC are associated with disease susceptibility; thus, we compared the glycosylation status of normal and several mutant forms of the murine prion protein (MuPrP) in cultured mammalian cells. Substitution

Subhabrata Biswas; Jan P. M. Langeveld; Donald Tipper; Shan Lu

2006-01-01

338

Use of capillary electrophoresis and fluorescent labeled peptides to detect the abnormal prion protein in the blood of animals that are infected with a transmissible spongiform encephalopathy  

Microsoft Academic Search

Transmissible spongiform encephalopathies in humans and in animals are fatal neuro-degenerative diseases with long incubation times. The putative cause of these diseases is a normal host protein, the prion protein, that becomes altered. This abnormal prion protein is found mostly in the brains of infected individuals in later stages of the disease, but also can be found in lymphoid and

Mary Jo Schmerr; Allen L Jenny; Marie S Bulgin; Janice M Miller; Amirali N Hamir; Randall C Cutlip; Kathryn R Goodwin

1999-01-01

339

Mutant prion protein D202N associated with familial prion disease is retained in the endoplasmic reticulum and forms ‘curly’ intracellular aggregates  

Microsoft Academic Search

Transmissible Spongiform Encephalopathies are fatal neurodegenerative disorders of humans and animals that are familial, sporadic,\\u000a and infectious in nature. Familial disorders of humans include Gerstmann-Straussler-Scheinker disease (GSS), familial Creutzfeldt-Jakob\\u000a disease (CJD), and fatal familial insomnia, and result from point mutations in the prion protein gene. Although neurotoxicity\\u000a in familial cases is believed to result from a spontaneous change in conformation

Yaping Gu; Susamma Verghese; Sharmila Bose; Maradumane Mohan; Neena Singh

2007-01-01

340

Crystallization and preliminary X-ray diffraction analysis of prion protein bound to the Fab fragment of the POM1 antibody  

PubMed Central

Prion diseases are neurodegenerative diseases that are characterized by the con­version of the cellular prion protein PrPc to the pathogenic isoform PrPsc. Several antibodies are known to interact with the cellular prion protein and to inhibit this transition. An antibody Fab fragment, Fab POM1, was produced that recognizes a structural motif of the C-terminal domain of mouse prion protein. To study the mechanism by which Fab POM1 recognizes and binds the prion molecule, the complex between Fab POM1 and the C-terminal domain of mouse prion (residues 120–232) was prepared and crystallized. Crystals of this binary complex belonged to the monoclinic space group C2, with unit-cell parameters a = 83.68, b = 106.9, c = 76.25?Å, ? = 95.6°.

Baral, Pravas Kumar; Wieland, Barbara; Swayampakula, Mridula; Polymenidou, Magdalini; Aguzzi, Adriano; Kav, Nat N. V.; James, Michael N. G.

2011-01-01

341

Disinfectants and Prions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Prions are novel pathogens that are believed to be composed solely of protein. They are capable of converting a normal cellular protein into the infectious isoform and thereby propagating an infection. Prion infections are characterized by a long asymptomatic incubation period followed by a relative...

342

Failure of Prion Protein Oxidative Folding Guides the Formation of Toxic Transmembrane Forms*  

PubMed Central

The mechanism by which pathogenic mutations in the globular domain of the cellular prion protein (PrPC) increase the likelihood of misfolding and predispose to diseases is not yet known. Differences in the evidences provided by structural and metabolic studies of these mutants suggest that in vivo folding could be playing an essential role in their pathogenesis. To address this role, here we use the single or combined M206S and M213S artificial mutants causing labile folds and express them in cells. We find that these mutants are highly toxic, fold as transmembrane PrP, and lack the intramolecular disulfide bond. When the mutations are placed in a chain with impeded transmembrane PrP formation, toxicity is rescued. These results suggest that oxidative folding impairment, as on aging, can be fundamental for the genesis of intracellular neurotoxic intermediates key in prion neurodegenerations.

Lisa, Silvia; Domingo, Beatriz; Martinez, Javier; Gilch, Sabine; Llopis, Juan F.; Schatzl, Hermann M.; Gasset, Maria

2012-01-01

343

Essential role of coiled-coils for aggregation and activity of Q/N-rich prions and polyQ proteins  

PubMed Central

SUMMARY The functional switch of glutamine/asparagine (Q/N)-rich prions and the neurotoxicity of polyQ-expanded proteins involve complex aggregation-prone structural transitions, commonly presumed to be forming ?-sheets. By analyzing sequences of interaction partners of these proteins, we discovered a recurrent presence of coiled-coil domains both in the partners and in segments that flank or overlap Q/N-rich and polyQ domains. Since coiled-coils can mediate protein interactions and multimerization, we studied their possible involvement in Q/N-rich and polyQ aggregations. Using circular dichroism and chemical cross-linking, we found that Q/N-rich and polyQ peptides form ?-helical coiled-coils in vitro and assemble into multimers. Using structure-guided mutagenesis, we found that coiled-coil domains modulate in vivo properties of two Q/N-rich prions and polyQ-expanded huntingtin. Mutations that disrupt coiled-coils impair aggregation and activity, whereas mutations that enhance coiled-coil propensity promote aggregation. These findings support a coiled-coil model for the functional switch of Q/N-rich prions and for the pathogenesis of polyQ-expansion diseases.

Fiumara, Ferdinando; Fioriti, Luana

2012-01-01

344

Mapping the Prion Protein Distribution in Marsupials: Insights from Comparing Opossum with Mouse CNS  

PubMed Central

The cellular form of the prion protein (PrPC) is a sialoglycoprotein widely expressed in the central nervous system (CNS) of mammalian species during neurodevelopment and in adulthood. The location of the protein in the CNS may play a role in the susceptibility of a species to fatal prion diseases, which are also known as the transmissible spongiform encephalopathies (TSEs). To date, little is known about PrPC distribution in marsupial mammals, for which no naturally occurring prion diseases have been reported. To extend our understanding of varying PrPC expression profiles in different mammals we carried out a detailed expression analysis of PrPC distribution along the neurodevelopment of the metatherian South American short-tailed opossum (Monodelphis domestica). We detected lower levels of PrPC in white matter fiber bundles of opossum CNS compared to mouse CNS. This result is consistent with a possible role for PrPC in the distinct neurodevelopment and neurocircuitry found in marsupials compared to other mammalian species.

Poggiolini, Ilaria; Legname, Giuseppe

2012-01-01

345

Palladium complexes affect the aggregation of human prion protein PrP106-126.  

PubMed

Many neurodegenerative disorders are induced by protein conformational change. Prion diseases are characterized by protein conformational conversion from a normal cellular form (PrP(C)) to an abnormal scrapie isoform (PrP(Sc)). PrP106-126 is an accepted model for studying the characteristics of PrP(Sc) because they share many biological and physiochemical properties. To understand how metal complexes affect the property of the prion peptide, the present work investigated interactions between Pd complexes and PrP106-126 based on our previous research using Pt and Au complexes to target the peptide. The selected compounds (Pd(phen)Cl(2), Pd(bipy)Cl(2), and Pd(en)Cl(2)) showed strong binding affinity to PrP106-126 and affected the conformation and aggregation of this active peptide in a different binding mode. Our results indicate that it may be the metal ligand-induced spatial effect rather the binding affinity that contributes to better inhibition on peptide aggregation. This finding would prove valuable in helping design and develop novel metallodrugs against prion diseases. PMID:21504185

Wang, Yanli; Feng, Li; Zhang, Bingbing; Wang, Xuesong; Huang, Cheng; Li, Yiming; Du, Weihong

2011-04-19

346

AGGREGATED, WILD-TYPE PRION PROTEIN CAUSES NEUROLOGICAL DYSFUNCTION AND SYNAPTIC ABNORMALITIES  

PubMed Central

The neurotoxic forms of the prion protein (PrP) that cause neurodegeneration in prion diseases remain to be conclusively identified. Considerable evidence points to the importance of non-infectious oligomers of PrP in the pathogenic process. In this study, we describe lines of Tg(WT) transgenic mice that over-express wild-type PrP by either ?5-fold or ?10-fold (depending on whether the transgene array is, respectively, hemizygous or homozygous). Homozygous but not hemizygous Tg(WT) mice develop a spontaneous neurodegenerative illness characterized clinically by tremor and paresis. Both kinds of mice accumulate large numbers of punctate PrP deposits in the molecular layer of the cerebellum as well as in several other brain regions, and they display abnormally enlarged synaptic terminals accompanied by a dramatic proliferation of membranous structures. The over-expressed PrP in Tg(WT) mice assembles into an insoluble form that is mildly protease-resistant and is recognizable by aggregation-specific antibodies, but that is not infectious in transmission experiments. Taken together, our results demonstrate that non-infectious aggregates of wild-type PrP are neurotoxic, particularly to synapses, and they suggest common pathogenic mechanisms shared by prion diseases and non-transmissible neurodegenerative disorders associated with protein misfolding.

Chiesa, Roberto; Piccardo, Pedro; Biasini, Emiliano; Ghetti, Bernardino; Harris, David A.

2008-01-01

347

Aggregation of cellular prion protein is initiated by proximity-induced dimerization  

PubMed Central

Prion diseases or transmissible spongiform encephalopathies (TSEs) are infectious and fatal neurodegenerative disorders in humans and animals. Pathological features of TSEs include the conversion of cellular prion protein (PrPC) into an altered disease-associated conformation generally designated PrPSc, abnormal deposition of PrPSc aggregates, and spongiform degeneration of the brain. The molecular steps leading to PrPC aggregation are unknown. Here, we have utilized an inducible oligomerization strategy to test if, in the absence of any infectious prion particles, the encounter between PrPC molecules may trigger its aggregation in neuronal cells. A chimeric PrPC composed of one (Fv1) or two (Fv2) modified FK506-binding protein (Fv) fused with PrPC were created, and transfected in N2a cells. Similar to PrPC, Fv1-PrP and Fv2-PrP were glycosylated, displayed normal localization, and anti-apoptotic function. When cells were treated with the dimeric Fv ligand AP20187, to induce dimerization (Fv1) or oligomerization (Fv2) of PrPC, both dimerization and oligomerization of PrPC resulted in the de novo production, release and deposition of extracellular PrP aggregates. Aggregates were insoluble in non-ionic detergents and partially resistant to proteinase K. These findings demonstrate that homologous interactions between PrPC molecules may constitute a minimal and sufficient molecular event leading to PrPC aggregation and extracellular deposition.

Goggin, Kevin; Bissonnette, Cyntia; Grenier, Catherine; Volkov, Leonid; Roucou, Xavier

2010-01-01

348

Detection of Type 1 Prion Protein in Variant Creutzfeldt-Jakob Disease  

PubMed Central

Molecular typing of the abnormal form of the prion protein (PrPSc) has come to be regarded as a powerful tool in the investigation of the prion diseases. All evidence thus far presented indicates a single PrPSc molecular type in variant Creutzfeldt-Jakob disease (termed type 2B), presumably resulting from infection with a single strain of the agent (bovine spongiform encephalopathy). Here we show for the first time that the PrPSc that accumulates in the brain in variant Creutzfeldt-Jakob disease also contains a minority type 1 component. This minority type 1 PrPSc was found in all 21 cases of variant Creutzfeldt-Jakob disease tested, irrespective of brain region examined, and was also present in the variant Creutzfeldt-Jakob disease tonsil. The quantitative balance between PrPSc types was maintained when variant Creutzfeldt-Jakob disease was transmitted to wild-type mice and was also found in bovine spongiform encephalopathy cattle brain, indicating that the agent rather than the host specifies their relative representation. These results indicate that PrPSc molecular typing is based on quantitative rather than qualitative phenomena and point to a complex relationship between prion protein biochemistry, disease phenotype and agent strain.

Yull, Helen M.; Ritchie, Diane L.; Langeveld, Jan P.M.; van Zijderveld, Fred G.; Bruce, Moira E.; Ironside, James W.; Head, Mark W.

2006-01-01

349

Limited transcriptional response of ovine microglia to prion accumulation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sheep scrapie (Sc) is the classical transmissible spongiform encephalopathy (prion disease). The conversion of normal cellular prion protein (PrPC) to disease-associated prion protein (PrPSc) is the fundamental pathogenesis of prion diseases. Many of the molecular mechanisms contributing to prion ...

350

Silencing of PrP C (prion protein) expression does not affect Brucella melitensis infection in human derived microglia cells.  

PubMed

Cellular prion proteins (PrP(C)) are mainly expressed in the central nervous system where they have antioxidant effects and a role in the endocytosis of bacteria within cells. These proteins also have some crucial biological functions including roles in neurotransmission, signal transduction and programmed cell death. However, the role of prion proteins in neuronal Brucella infection, specifically in the interaction of the pathogen and the host cell is controversial. In the present study, the silencing of PrP(C) mRNA by small interfering RNA (siRNA) transfection was investigated in human microglia cells infected with Brucella melitensis. More than 70% of prion proteins were down-regulated in microglia by siRNA transfection and this caused a slight decrease in the cellular viability of the control cells. Silencing of PrP(C) suppressed the antioxidant systems, though it led to an up-regulation of pro-inflammatory cytokines such as IL-12 and TNF-? as demonstrated by qRT-PCR analysis. B. melitensis infection of prion protein-silenced cells led to increase host viability, but had no effect on bacterial phagocytosis. According to the present study, there is no significant effect of prion proteins on phagocytosis and intracellular killing of B. melitensis in microglia cells. PMID:23820446

Erdogan, Suat; Duzguner, Vesile; Kucukgul, Altug; Aslantas, Ozkan

2013-06-29

351

Rational targeting for prion therapeutics.  

PubMed

Prions--pathogens that are lethal to humans and other animals--are thought to be conformational isomers of the cellular prion protein. Their unique biology, and the potential for a wider pathobiological significance of prion-like mechanisms, has motivated much research into understanding prion neurodegeneration. Moreover, concerns that extensive dietary exposure to bovine spongiform encephalopathy (BSE) prions might have infected many individuals--who might eventually develop its human counterpart, variant Creutzfeldt-Jakob disease (vCJD)--has focused much interest on therapeutics. The challenge of interrupting this aggressive, diffuse and uniformly fatal neurodegenerative process is daunting. However, the recent finding that the onset of clinical disease in established neuroinvasive prion infection in a mouse model can be halted and early pathology reversed is a source for considerable optimism. A therapeutic focus on the cellular prion protein, rather than prions themselves, which might not be directly neurotoxic, is suggested. PMID:15611724

Mallucci, Giovanna; Collinge, John

2005-01-01

352

Prions, From Structure to Epigenetics and Neuronal Functions  

NASA Astrophysics Data System (ADS)

Prions are a unique type of protein that can misfold and convert other proteins to the same shape. The well-characterized yeast prion [PSI+] is formed from an inactive amyloid fiber conformation of the translation-termination factor, Sup35. This altered conformation is passed from mother cells to daughters, acting as a template to perpetuate the prion state and providing a mechanism of protein-based inheritance. We employed a variety of methods to determine the structure of Sup35 amyloid fibrils. First, using fluorescent tags and cross-linking we identified specific segments of the protein monomer that form intermolecular contacts in a ``Head-to-Head,'' ``Tail-to-Tail'' fashion while a central region forms intramolecular contacts. Then, using peptide arrays we mapped the region responsible for the prion transmission barrier between two different yeast species. We have also used optical tweezers to reveal that the non-covalent intermolecular contacts between monomers are unusually strong, and maintain fibril integrity even under forces that partially unfold individual monomers and extend fibril length. Based on the handful of known yeast prion proteins we predicted sequences that could be responsible for prion-like amyloid folding. Our screen identified 19 new candidate prions, whose protein-folding properties and diverse cellular functions we have characterized using a combination of genetic and biochemical techniques. Prion-driven phenotypic diversity increases under stress, and can be amplified by the dynamic maturation of prion-initiating states. These qualities allow prions to act as ``bet-hedging'' devices that facilitate the adaptation of yeast to stressful environments, and might speed the evolution of new traits. Together with Kandel and Si, we have also found that a regulatory protein that plays an important role in synaptic plasticity behaves as a prion in yeast. Cytoplasmic polyAdenylation element binding protein, CPEB, maintains synapses by promoting the local translation of mRNAs. We postulate that the self-perpetuating folding of the prion domain acts as a molecular memory. Thus yeast prions have provided evidence for the surprising possibility that amyloid protein folds can serve as the basis for memory and inheritance.

Lindquist, Susan

2012-02-01

353

Prion infection of differentiated neurospheres  

Microsoft Academic Search

Until now only a few cell lines have been proved able to propagate prions and only limited prion strains have been replicated in cell models. Neurosphere lines isolated from the brains of mice at embryonic day 14 grow as aggregates and contain CNS stem cells. Others authors have previously reported that cultured neurospheres expressing cellular prion protein (PrPC) can be

Maria Eugenia Herva; Aroa Relaño-Ginés; Ana Villa; Juan María Torres

2010-01-01

354

The toxicity of antiprion antibodies is mediated by the flexible tail of the prion protein.  

PubMed

Prion infections cause lethal neurodegeneration. This process requires the cellular prion protein (PrP(C); ref. 1), which contains a globular domain hinged to a long amino-proximal flexible tail. Here we describe rapid neurotoxicity in mice and cerebellar organotypic cultured slices exposed to ligands targeting the ?1 and ?3 helices of the PrP(C) globular domain. Ligands included seven distinct monoclonal antibodies, monovalent Fab1 fragments and recombinant single-chain variable fragment miniantibodies. Similar to prion infections, the toxicity of globular domain ligands required neuronal PrP(C), was exacerbated by PrP(C) overexpression, was associated with calpain activation and was antagonized by calpain inhibitors. Neurodegeneration was accompanied by a burst of reactive oxygen species, and was suppressed by antioxidants. Furthermore, genetic ablation of the superoxide-producing enzyme NOX2 (also known as CYBB) protected mice from globular domain ligand toxicity. We also found that neurotoxicity was prevented by deletions of the octapeptide repeats within the flexible tail. These deletions did not appreciably compromise globular domain antibody binding, suggesting that the flexible tail is required to transmit toxic signals that originate from the globular domain and trigger oxidative stress and calpain activation. Supporting this view, various octapeptide ligands were not only innocuous to both cerebellar organotypic cultured slices and mice, but also prevented the toxicity of globular domain ligands while not interfering with their binding. We conclude that PrP(C) consists of two functionally distinct modules, with the globular domain and the flexible tail exerting regulatory and executive functions, respectively. Octapeptide ligands also prolonged the life of mice expressing the toxic PrP(C) mutant, PrP(?94-134), indicating that the flexible tail mediates toxicity in two distinct PrP(C)-related conditions. Flexible tail-mediated toxicity may conceivably play a role in further prion pathologies, such as familial Creutzfeldt-Jakob disease in humans bearing supernumerary octapeptides. PMID:23903654

Sonati, Tiziana; Reimann, Regina R; Falsig, Jeppe; Baral, Pravas Kumar; O'Connor, Tracy; Hornemann, Simone; Yaganoglu, Sine; Li, Bei; Herrmann, Uli S; Wieland, Barbara; Swayampakula, Mridula; Rahman, Muhammad Hafizur; Das, Dipankar; Kav, Nat; Riek, Roland; Liberski, Pawel P; James, Michael N G; Aguzzi, Adriano

2013-07-31

355

Accumulation of Pathological Prion Protein PrPSc in the Skin of Animals with Experimental and Natural Scrapie  

PubMed Central

Prion infectivity and its molecular marker, the pathological prion protein PrPSc, accumulate in the central nervous system and often also in lymphoid tissue of animals or humans affected by transmissible spongiform encephalopathies. Recently, PrPSc was found in tissues previously considered not to be invaded by prions (e.g., skeletal muscles). Here, we address the question of whether prions target the skin and show widespread PrPSc deposition in this organ in hamsters perorally or parenterally challenged with scrapie. In hamsters fed with scrapie, PrPSc was detected before the onset of symptoms, but the bulk of skin-associated PrPSc accumulated in the clinical phase. PrPSc was localized in nerve fibres within the skin but not in keratinocytes, and the deposition of PrPSc in skin showed no dependence from the route of infection and lymphotropic dissemination. The data indicated a neurally mediated centrifugal spread of prions to the skin. Furthermore, in a follow-up study, we examined sheep naturally infected with scrapie and detected PrPSc by Western blotting in skin samples from two out of five animals. Our findings point to the skin as a potential reservoir of prions, which should be further investigated in relation to disease transmission.

Wrede, Arne; Wemheuer, Wilhelm; Brenig, Bertram; Kratzel, Christine; Lemmer, Karin; Beekes, Michael

2007-01-01

356

Kinetics of amyloid aggregation: a study of the GNNQQNY prion sequence.  

PubMed

The small amyloid-forming GNNQQNY fragment of the prion sequence has been the subject of extensive experimental and numerical studies over the last few years. Using unbiased molecular dynamics with the OPEP coarse-grained potential, we focus here on the onset of aggregation in a 20-mer system. With a total of 16.9 ?s of simulations at 280 K and 300 K, we show that the GNNQQNY aggregation follows the classical nucleation theory (CNT) in that the number of monomers in the aggregate is a very reliable descriptor of aggregation. We find that the critical nucleus size in this finite-size system is between 4 and 5 monomers at 280 K and 5 and 6 at 300 K, in overall agreement with experiment. The kinetics of growth cannot be fully accounted for by the CNT, however. For example, we observe considerable rearrangements after the nucleus is formed, as the system attempts to optimize its organization. We also clearly identify two large families of structures that are selected at the onset of aggregation demonstrating the presence of well-defined polymorphism, a signature of amyloid growth, already in the 20-mer aggregate. PMID:23209391

Nasica-Labouze, Jessica; Mousseau, Normand

2012-11-29

357

Kinetics of Amyloid Aggregation: A Study of the GNNQQNY Prion Sequence  

PubMed Central

The small amyloid-forming GNNQQNY fragment of the prion sequence has been the subject of extensive experimental and numerical studies over the last few years. Using unbiased molecular dynamics with the OPEP coarse-grained potential, we focus here on the onset of aggregation in a 20-mer system. With a total of 16.9 of simulations at 280 K and 300 K, we show that the GNNQQNY aggregation follows the classical nucleation theory (CNT) in that the number of monomers in the aggregate is a very reliable descriptor of aggregation. We find that the critical nucleus size in this finite-size system is between 4 and 5 monomers at 280 K and 5 and 6 at 300 K, in overall agreement with experiment. The kinetics of growth cannot be fully accounted for by the CNT, however. For example, we observe considerable rearrangements after the nucleus is formed, as the system attempts to optimize its organization. We also clearly identify two large families of structures that are selected at the onset of aggregation demonstrating the presence of well-defined polymorphism, a signature of amyloid growth, already in the 20-mer aggregate.

Nasica-Labouze, Jessica; Mousseau, Normand

2012-01-01

358

Ablation of the metal ion-induced endocytosis of the prion protein by disease-associated mutation of the octarepeat region  

Microsoft Academic Search

The neurodegenerative spongiform encephalopathies, or prion diseases, are characterized by the conversion of the normal cellular form of the prion protein PrPC to a pathogenic form, PrPSc[1]. There are four copies of an octarepeat PHGG(G\\/S)WGQ that specifically bind Cu2+ ions within the N-terminal half of PrPC[2–4]. This has led to proposals that prion diseases may, in part, be due to

W. Sumudhu S. Perera; Nigel M. Hooper

2001-01-01

359

A simple quantitative model of macromolecular crowding effects on protein folding: Application to the murine prion protein(121-231)  

NASA Astrophysics Data System (ADS)

A model of protein folding kinetics is applied to study the effects of macromolecular crowding on protein folding rate and stability. Macromolecular crowding is found to promote a decrease of the entropic cost of folding of proteins that produces an increase of both the stability and the folding rate. The acceleration of the folding rate due to macromolecular crowding is shown to be a topology-dependent effect. The model is applied to the folding dynamics of the murine prion protein (121-231). The differential effect of macromolecular crowding as a function of protein topology suffices to make non-native configurations relatively more accessible.

Bergasa-Caceres, Fernando; Rabitz, Herschel A.

2013-06-01

360

Hsp104 drives "protein-only" positive selection of Sup35 prion strains encoding strong [PSI(+)].  

PubMed

Structurally distinct, self-templating prion "strains" can encode distinct phenotypes and amplify at different rates depending upon the environment. Indeed, prion strain ensembles can evolve in response to environmental challenges, which makes them highly challenging drug targets. It is not understood how the proteostasis network amplifies one prion strain at the expense of another. Here, we demonstrate that Hsp104 remodels the distinct intermolecular contacts of different synthetic Sup35 prion strains in a way that selectively amplifies prions encoding strong [PSI(+)] and simultaneously eliminates prions encoding weak [PSI(+)]. Hsp104 has reduced ability to fragment prions encoding weak [PSI(+)], but readily converts them to nontemplating forms. By contrast, Hsp104 readily fragments prions encoding strong [PSI(+)], but has reduced ability to eliminate their infectivity. Thus, we illuminate direct mechanisms underpinning how the proteostasis network can drive prion strain selection. PMID:23177195

DeSantis, Morgan E; Shorter, James

2012-11-21

361

Nanoimaging for prion related diseases  

PubMed Central

Misfolding and aggregation of prion proteins is linked to a number of neurodegenerative disorders such as Creutzfeldt-Jacob disease (CJD) and its variants: Kuru, Gerstmann-Straussler-Scheinker syndrome and fatal familial insomnia. In prion diseases, infectious particles are proteins that propagate by transmitting a misfolded state of a protein, leading to the formation of aggregates and ultimately to neurodegeneration. Prion phenomenon is not restricted to humans. There are a number of prion-related diseases in a variety of mammals, including bovine spongiform encephalopathy (BSE, also known as “mad cow disease”) in cattle. All known prion diseases, collectively called transmissible spongiform encephalopathies (TSEs), are untreatable and fatal. Prion proteins were also found in some fungi where they are responsible for heritable traits. Prion proteins in fungi are easily accessible and provide a powerful model for understanding the general principles of prion phenomenon and molecular mechanisms of mammalian prion diseases. Presently, several fundamental questions related to prions remain unanswered. For example, it is not clear how prions cause the disease. Other unknowns include the nature and structure of infectious agent and how prions replicate. Generally, the phenomenon of misfolding of the prion protein into infectious conformations that have the ability to propagate their properties via aggregation is of significant interest. Despite the crucial importance of misfolding and aggregation, very little is currently known about the molecular mechanisms of these processes. While there is an apparent critical need to study molecular mechanisms underlying misfolding and aggregation, the detailed characterization of these single molecule processes is hindered by the limitation of conventional methods. Although some issues remain unresolved, much progress has been recently made primarily due to the application of nanoimaging tools. The use of nanoimaging methods shows great promise for understanding the molecular mechanisms of prion phenomenon, possibly leading toward early diagnosis and effective treatment of these devastating diseases. This review article summarizes recent reports which advanced our understanding of the prion phenomenon through the use of nanoimaging methods.

Portillo, Alexander M; Deckert-Gaudig, Tanja; Deckert, Volker

2010-01-01

362

Nanoimaging for prion related diseases.  

PubMed

Misfolding and aggregation of prion proteins is linked to a number of neurodegenerative disorders such as Creutzfeldt-Jacob disease (CJD) and its variants: Kuru, Gerstmann-Straussler-Scheinker syndrome and fatal familial insomnia. In prion diseases, infectious particles are proteins that propagate by transmitting a misfolded state of a protein, leading to the formation of aggregates and ultimately to neurodegeneration. Prion phenomenon is not restricted to humans. There are a number of prion-related diseases in a variety of mammals, including bovine spongiform encephalopathy (BSE, also known as "mad cow disease") in cattle. All known prion diseases, collectively called transmissible spongiform encephalopathies (TSEs), are untreatable and fatal. Prion proteins were also found in some fungi where they are responsible for heritable traits. Prion proteins in fungi are easily accessible and provide a powerful model for understanding the general principles of prion phenomenon and molecular mechanisms of mammalian prion diseases. Presently, several fundamental questions related to prions remain unanswered. For example, it is not clear how prions cause the disease. Other unknowns include the nature and structure of infectious agent and how prions replicate. Generally, the phenomenon of misfolding of the prion protein into infectious conformations that have the ability to propagate their properties via aggregation is of significant interest. Despite the crucial importance of misfolding and aggregation, very little is currently known about the molecular mechanisms of these processes. While there is an apparent critical need to study molecular mechanisms underlying misfolding and aggregation, the detailed characterization of these single molecule processes is hindered by the limitation of conventional methods. Although some issues remain unresolved, much progress has been recently made primarily due to the application of nanoimaging tools. The use of nanoimaging methods shows great promise for understanding the molecular mechanisms of prion phenomenon, possibly leading toward early diagnosis and effective treatment of these devastating diseases. This review article summarizes recent reports which advanced our understanding of the prion phenomenon through the use of nanoimaging methods. PMID:20724837

Krasnoslobodtsev, Alexey V; Portillo, Alexander M; Deckert-Gaudig, Tanja; Deckert, Volker; Lyubchenko, Yuri L

2010-10-23

363

Prion Protein and Shadoo Are Involved in Overlapping Embryonic Pathways and Trophoblastic Development  

PubMed Central

The potential requirement of either the Prion or Shadoo protein for early mouse embryogenesis was recently suggested. However, the current data did not allow to precise the developmental process that was affected in the absence of both proteins and that led to the observed early lethal phenotype. In the present study, using various Prnp transgenic mouse lines and lentiviral vectors expressing shRNAs that target the Shadoo-encoding mRNA, we further demonstrate the specific requirement of at least one of these two PrP-related proteins at early developmental stages. Histological analysis reveals developmental defect of the ectoplacental cone and important hemorrhage surrounding the Prnp-knockout-Sprn-knockdown E7.5 embryos. By restricting the RNA interference to the trophoblastic cell lineages, the observed lethal phenotype could be attributed to the sole role of these proteins in this trophectoderm-derived compartment. RNAseq analysis performed on early embryos of various Prnp and Sprn genotypes indicated that the simultaneous down-regulation of these two proteins affects cell-adhesion and inflammatory pathways as well as the expression of ectoplacental-specific genes. Overall, our data provide biological clues in favor of a crucial and complementary embryonic role of the prion protein family in Eutherians and emphasizes the need to further evaluate its implication in normal and pathological human placenta biology.

Makhzami, Samira; Vilotte, Marthe; Jaffrezic, Florence; Halliez, Sophie; Bouet, Stephan; Marthey, Sylvain; Khalife, Manal; Kanellopoulos-Langevin, Colette; Beringue, Vincent; Le Provost, Fabienne; Laude, Hubert; Vilotte, Jean-Luc

2012-01-01

364

Prion protein expression alters APP cleavage without interaction with BACE-1.  

PubMed

The prion protein (PrP) and the beta-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE-1) are both copper binding proteins, but are associated with two separate neurodegenerative diseases. The role of BACE-1 in the formation of beta-amyloid has made it a major target in attempts to reduce the formation of beta-amyloid in Alzheimer's diseases. However, the suggestion that PrP, normally associated with prion diseases, binds to BACE-1 and reduces its activity has led to the suggestion that the study of this interaction could be of considerable importance to Alzheimer's disease. We therefore undertook to investigate the possible interaction of these two proteins physically and at the level of transcription, translation and APP cleavage. Our findings suggest that mature PrP and BACE-1 do not physically interact, but that altered PrP expression results in altered BACE-1 protein expression and promoter activity. Additionally, overexpression of PrP results in increased cleavage of APP in contrast to previous datas suggesting a reduction. Our findings suggest that any relation between PrP and BACE-1 is indirect. Altered expression of PrP causes changes in the expression of many other proteins which may be as a result of altered copper metabolism. PMID:22796214

McHugh, Patrick C; Wright, Josephine A; Williams, Robert J; Brown, David R

2012-07-10

365

Prion formation correlates with activation of translation-regulating protein 4E-BP and neuronal transcription factor Elk1.  

PubMed

Cellular mechanisms play a role in conversion of the normal prion protein PrP(C) to the disease-associated protein PrP(Sc). The cells provide not only PrP(C), but also still largely undefined factors required for efficient prion replication. Previously, we have observed that interference with ERK and p38-JNK MAP kinase pathways has opposing effects on the formation of prions indicating that the process is regulated by a balance in intracellualar signaling pathways. In order to obtain a "flow-chart" of such pathways, we here studied the activation of MEK/ERK and mTORC1 downstream targets in relation to PrP(Sc) accumulation in GT1-1 cells infected with the RML or 22L prion strains. We show that inhibition of mTORC1 with rapamycin causes a reduction of PrP(Sc) accumulation at similar low levels as seen when the interaction between the translation initiation factors eIF4E and eIF4G downstream mTORC1 is inhibited using 4EGI-1. No effect is seen following the inhibition of molecules (S6K1 and Mnk1) that links MEK/ERK signaling to mTORC1-mediated control of translation. Instead, stimulation (high [KCl] or [serum]) or inhibition (MEK-inhibitor) of prion formation is associated with increased or decreased phosphorylation of the neuronal transcription factor Elk1, respectively. This study shows that prion formation can be modulated by translational initiating factors, and suggests that MEK/ERK signaling plays a role in the conversion of PrP(C) to PrP(Sc) via an Elk1-mediated transcriptional control. Altogether, our studies indicate that prion protein conversion is under the control of intracellular signals, which hypothetically, under certain conditions may elicit irreversible responses leading to progressive neurodegenerative diseases. PMID:23742760

Allard, Elin K; Grujic, Mirjana; Fisone, Gilberto; Kristensson, Krister

2013-06-03

366

The Landscape of the Prion Protein's Structural Response to Mutation Revealed by Principal Component Analysis of Multiple NMR Ensembles  

PubMed Central

Prion Proteins (PrP) are among a small number of proteins for which large numbers of NMR ensembles have been resolved for sequence mutants and diverse species. Here, we perform a comprehensive principle components analysis (PCA) on the tertiary structures of PrP globular proteins to discern PrP subdomains that exhibit conformational change in response to point mutations and clade-specific evolutionary sequence mutation trends. This is to our knowledge the first such large-scale analysis of multiple NMR ensembles of protein structures, and the first study of its kind for PrPs. We conducted PCA on human (n?=?11), mouse (n?=?14), and wildtype (n?=?21) sets of PrP globular structures, from which we identified five conformationally variable subdomains within PrP. PCA shows that different non-local patterns and rankings of variable subdomains arise for different pathogenic mutants. These subdomains may thus be key areas for initiating PrP conversion during disease. Furthermore, we have observed the conformational clustering of divergent TSE-non-susceptible species pairs; these non-phylogenetic clusterings indicate structural solutions towards TSE resistance that do not necessarily coincide with evolutionary divergence. We discuss the novelty of our approach and the importance of PrP subdomains in structural conversion during disease.

Gendoo, Deena M. A.; Harrison, Paul M.

2012-01-01

367

Role of ADAMs in the Ectodomain Shedding and Conformational Conversion of the Prion Protein*  

PubMed Central

The cellular prion protein (PrPC) is essential for the pathogenesis and transmission of prion diseases. PrPC is bound to the plasma membrane via a glycosylphosphatidylinositol anchor, although a secreted, soluble form has also been identified. Previously we reported that PrPC is subject to ectodomain shedding from the membrane by zinc metalloproteinases with a similar inhibition profile to those involved in shedding the amyloid precursor protein. Here we have used gain-of-function (overexpression) and loss-of-function (small interfering RNA knockdown) experiments in cells to identify the ADAMs (a disintegrin and metalloproteinases) involved in the ectodomain shedding of PrPC. These experiments revealed that ADAM9 and ADAM10, but not ADAM17, are involved in the shedding of PrPC and that ADAM9 exerts its effect on PrPC shedding via ADAM10. Using dominant negative, catalytically inactive mutants, we show that the catalytic activity of ADAM9 is required for its effect on ADAM10. Mass spectrometric analysis revealed that ADAM10, but not ADAM9, cleaved PrP between Gly228 and Arg229, three residues away from the site of glycosylphosphatidylinositol anchor attachment. The shedding of another membrane protein, the amyloid precursor protein ?-secretase BACE1, by ADAM9 is also mediated via ADAM10. Furthermore, we show that pharmacological inhibition of PrPC shedding or activation of both PrPC and PrPSc shedding by ADAM10 overexpression in scrapie-infected neuroblastoma N2a cells does not alter the formation of proteinase K-resistant PrPSc. Collectively, these data indicate that although PrPC can be shed through the action of ADAM family members, modulation of PrPC or PrPSc ectodomain shedding does not regulate prion conversion.

Taylor, David R.; Parkin, Edward T.; Cocklin, Sarah L.; Ault, James R.; Ashcroft, Alison E.; Turner, Anthony J.; Hooper, Nigel M.

2009-01-01

368

Conservation of a portion of the S. cerevisiae Ure2p prion domain that interacts with the full-length protein  

PubMed Central

The [URE3] prion of Saccharomyces cerevisiae is a self-propagating inactive amyloid form of the Ure2 protein. Ure2p residues 1–65 constitute the prion domain, and the remaining C-terminal portion regulates nitrogen catabolism. We have examined the URE2 genes of wild-type isolates of S. cerevisiae and those of several pathogenic yeasts and a filamentous fungus. We find that the normal function of the S. cerevisiae Ure2p in nitrogen regulation is fully complemented by the Ure2p of Candida albicans, Candida glabrata, Candida kefyr, Candida maltosa, Saccharomyces bayanus, and Saccharomyces paradoxus, all of which have high homology in the C-terminal nitrogen regulation domain. However, there is considerable divergence of their N-terminal domains from that of Ure2p of S. cerevisiae. [URE3Sc] showed efficient transmission into S. cerevisiae ure2? cells if expressing a Ure2p of species within Saccharomyces. However, [URE3Sc] did not seed self-propagating inactivation of the Ure2p's from the other yeasts. When overexpressed as a fusion with green fluorescent protein, residues 5–47 of the S. cerevisiae prion domain are necessary for curing the [URE3] prion. Residues 11–39 are necessary for an inactivating interaction with the full-length Ure2p. A nearly identical region is highly conserved among many of the yeasts examined in this study, despite the wide divergence of sequences found in other parts of the N-terminal domains.

Edskes, Herman K.; Wickner, Reed B.

2002-01-01

369

Interaction between a recombinant prion protein and organo-mineral complexes as evidenced by CPMAS 13C-NMR  

NASA Astrophysics Data System (ADS)

Prion proteins (PrP) are the main responsible for Transmissible Spongiform Encephalopathies (TSE). The TSE etiological agent is a misfolded form of the normal cellular prion protein. The amyloidal aggregates accumulated in the brain of infected animals and mainly composed of PrPSc exhibit resistance to protease attack and many conventional inactivating procedures. The prion protein diseases cause an environmental issue because the environment and in particular the soil compartment can be contaminated and then become a potential reservoir and diffuser of TSEs infectivity as a consequence of (i) accidental dispersion from storage plants of meat and bone meal, (ii) incorporation of contaminated material in fertilizers, (iii) possible natural contamination of pasture soils by grazing herds, and (v) burial of carcasses. The environmental problem can be even more relevant because very low amounts of PrPSc are able to propagate the disease. Several studies evidenced that infectious prion protein remains active in soils for years. Contaminated soils result, thus, a possible critical route of TSE transmission in wild animals. Soil can also protect prion protein toward degradation processes due to the presence of humic substances and inorganic components such as clays. Mineral and organic colloids and the more common association between clay minerals and humic substances can contribute to the adsorption/entrapment of molecules and macromolecules. The polymerization of organic monomeric humic precursors occurring in soil in the presence of oxidative enzymes or manganese and iron oxides, is considered one of the most important processes contributing to the formation of humic substances. The process is very fast and produces a population of polymeric products of different molecular structures, sizes, shapes and complexity. Other molecules and possibly biomacromolecules such as proteins may be involved. The aim of the present work was to study by CPMAS 13C-NMR the interactions between a non pathogenic ovine recombinant prion protein and a model soil system represented by a manganese oxide in the form of birnessite (?-MnO2), coated with a polymerized catechol. To better understand the effect of the polymerization process, PrP was added to the birnessite-cathecol system either before or after the polymerization processes. The NMR spectra of the prion protein interacting directly with birnessite revealed disappearance of the signals due to the paramagnetic nature of manganese oxide or abiotic degradation. Conversely, the signal pattern of the protein re-appeared as it is mixed to the soil-like system either during or after the catechol polymerization process. Results suggested that the possible interactions of the prion protein on soil systems can be mediated by natural organic matter. However, deeper studies on more complex real soil systems are needed to definitely confirm such hypothesis.

Russo, F.; Scotti, R.; Gianfreda, L.; Conte, P.; Rao, M. A.

2009-04-01

370

Cyclosporin-A-induced prion protein aggresomes are dynamic quality-control cellular compartments.  

PubMed

Despite the activity of cellular quality-control mechanisms, subsets of mature and newly synthesized polypeptides fail to fold properly and form insoluble aggregates. In some cases, protein aggregation leads to the development of human neurodegenerative maladies, including Alzheimer's and prion diseases. Aggregates of misfolded prion protein (PrP), which appear in cells after exposure to the drug cyclosporin A (CsA), and disease-linked PrP mutants have been found to accumulate in juxtanuclear deposition sites termed 'aggresomes'. Recently, it was shown that cells can contain at least two types of deposition sites for misfolded proteins: a dynamic quality-control compartment, which was termed 'JUNQ', and a site for terminally aggregated proteins called 'IPOD'. Here, we show that CsA-induced PrP aggresomes are dynamic structures that form despite intact proteasome activity, recruit chaperones and dynamically exchange PrP molecules with the cytosol. These findings define the CsA-PrP aggresome as a JUNQ-like dynamic quality-control compartment that mediates the refolding or degradation of misfolded proteins. Together, our data suggest that the formation of PrP aggresomes protects cells from proteotoxic stress. PMID:21558416

Ben-Gedalya, Tziona; Lyakhovetsky, Roman; Yedidia, Yifat; Bejerano-Sagie, Michal; Kogan, Natalya M; Karpuj, Marcela Viviana; Kaganovich, Daniel; Cohen, Ehud

2011-05-10

371

The Comprehensive Native Interactome of a Fully Functional Tagged Prion Protein  

PubMed Central

The enumeration of the interaction partners of the cellular prion protein, PrPC, may help clarifying its elusive molecular function. Here we added a carboxy proximal myc epitope tag to PrPC. When expressed in transgenic mice, PrPmyc carried a GPI anchor, was targeted to lipid rafts, and was glycosylated similarly to PrPC. PrPmyc antagonized the toxicity of truncated PrP, restored prion infectibility of PrPC-deficient mice, and was physically incorporated into PrPSc aggregates, indicating that it possessed all functional characteristics of genuine PrPC. We then immunopurified myc epitope-containing protein complexes from PrPmyc transgenic mouse brains. Gentle differential elution with epitope-mimetic decapeptides, or a scrambled version thereof, yielded 96 specifically released proteins. Quantitative mass spectrometry with isotope-coded tags identified seven proteins which co-eluted equimolarly with PrPC and may represent component of a multiprotein complex. Selected PrPC interactors were validated using independent methods. Several of these proteins appear to exert functions in axomyelinic maintenance.

Moos, Rita; Brunner, Erich; Rulicke, Thomas; Calella, Anna Maria; Aguzzi, Adriano

2009-01-01

372

Degradation of the Disease-Associated Prion Protein by a Serine Protease from Lichens  

PubMed Central

The disease-associated prion protein (PrPTSE), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrPTSE inactivation by lichens and found acetone extracts of three lichen species (Parmelia sulcata, Cladonia rangiferina and Lobaria pulmonaria) have the ability to degrade prion protein (PrP) from TSE-infected hamsters, mice and deer. Immunoblots measuring PrP levels and protein misfolding cyclic amplification indicated at least two logs of reductions in PrPTSE. Degradative activity was not found in closely related lichen species or in algae or a cyanobacterium that inhabit lichens. Degradation was blocked by Pefabloc SC, a serine protease inhibitor, but not inhibitors of other proteases or enzymes. Additionally, we found that PrP levels in PrPTSE-enriched preps or infected brain homogenates are also reduced following exposure to freshly-collected P. sulcata or an aqueous extract of the lichen. Our findings indicate that these lichen extracts efficiently degrade PrPTSE and suggest that some lichens could have potential to inactivate TSE infectivity on the landscape or be a source for agents to degrade prions. Further work to clone and characterize the protease, assess its effect on TSE infectivity and determine which organism or organisms present in lichens produce or influence the protease activity is warranted.

Johnson, Christopher J.; Bennett, James P.; Biro, Steven M.; Duque-Velasquez, Juan Camilo; Rodriguez, Cynthia M.; Bessen, Richard A.; Rocke, Tonie E.

2011-01-01

373

Degradation of the disease-associated prion protein by a serine protease from lichens.  

PubMed

The disease-associated prion protein (PrP(TSE)), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrP(TSE) inactivation by lichens and found acetone extracts of three lichen species (Parmelia sulcata, Cladonia rangiferina and Lobaria pulmonaria) have the ability to degrade prion protein (PrP) from TSE-infected hamsters, mice and deer. Immunoblots measuring PrP levels and protein misfolding cyclic amplification indicated at least two logs of reductions in PrP(TSE). Degradative activity was not found in closely related lichen species or in algae or a cyanobacterium that inhabit lichens. Degradation was blocked by Pefabloc SC, a serine protease inhibitor, but not inhibitors of other proteases or enzymes. Additionally, we found that PrP levels in PrP(TSE)-enriched preps or infected brain homogenates are also reduced following exposure to freshly-collected P. sulcata or an aqueous extract of the lichen. Our findings indicate that these lichen extracts efficiently degrade PrP(TSE) and suggest that some lichens could have potential to inactivate TSE infectivity on the landscape or be a source for agents to degrade prions. Further work to clone and characterize the protease, assess its effect on TSE infectivity and determine which organism or organisms present in lichens produce or influence the protease activity is warranted. PMID:21589935

Johnson, Christopher J; Bennett, James P; Biro, Steven M; Duque-Velasquez, Juan Camilo; Rodriguez, Cynthia M; Bessen, Richard A; Rocke, Tonie E

2011-05-11

374

Degradation of the disease-associated prion protein by a serine protease from lichens  

USGS Publications Warehouse

The disease-associated prion protein (PrPTSE), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrPTSE inactivation by lichens and found acetone extracts of three lichen species (Parmelia sulcata, Cladonia rangiferina and Lobaria pulmonaria) have the ability to degrade prion protein (PrP) from TSE-infected hamsters, mice and deer. Immunoblots measuring PrP levels and protein misfolding cyclic amplification indicated at least two logs of reductions in PrPTSE. Degradative activity was not found in closely related lichen species or in algae or a cyanobacterium that inhabit lichens. Degradation was blocked by Pefabloc SC, a serine protease inhibitor, but not inhibitors of other proteases or enzymes. Additionally, we found that PrP levels in PrPTSE-enriched preps or infected brain homogenates are also reduced following exposure to freshly-collected P. sulcata or an aqueous extract of the lichen. Our findings indicate that these lichen extracts efficiently degrade PrPTSE and suggest that some lichens could have potential to inactivate TSE infectivity on the landscape or be a source for agents to degrade prions. Further work to clone and characterize the protease, assess its effect on TSE infectivity and determine which organism or organisms present in lichens produce or influence the protease activity is warranted.

Johnson, C. J.; Bennett, J. P.; Biro, S. M.; Duque-Velasquez, J. C.; Rodriguez, C. M.; Bessen, R. A.; Rocke, T. E.

2011-01-01

375

Degradation of the disease-associated prion protein by a serine protease from lichens  

USGS Publications Warehouse

The disease-associated prion protein (PrP(TSE)), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrP(TSE) inactivation by lichens and found acetone extracts of three lichen species (Parmelia sulcata, Cladonia rangiferina and Lobaria pulmonaria) have the ability to degrade prion protein (PrP) from TSE-infected hamsters, mice and deer. Immunoblots measuring PrP levels and protein misfolding cyclic amplification indicated at least two logs of reductions in PrP(TSE). Degradative activity was not found in closely related lichen species or in algae or a cyanobacterium that inhabit lichens. Degradation was blocked by Pefabloc SC, a serine protease inhibitor, but not inhibitors of other proteases or enzymes. Additionally, we found that PrP levels in PrP(TSE)-enriched preps or infected brain homogenates are also reduced following exposure to freshly-collected P. sulcata or an aqueous extract of the lichen. Our findings indicate that these lichen extracts efficiently degrade PrP(TSE) and suggest that some lichens could have potential to inactivate TSE infectivity on the landscape or be a source for agents to degrade prions. Further work to clone and characterize the protease, assess its effect on TSE infectivity and determine which organism or organisms present in lichens produce or influence the protease activity is warranted.

Johnson, C.J.; Bennett, J.P.; Biro, S.M.; Duque-Velasquez, J.C.; Rodriguez, C.M.; Bessen, R.A.; Rocke, T.E.

2011-01-01

376

Degradation of the disease-associated prion protein by a serine protease from lichens.  

USGS Publications Warehouse

The disease-associated prion protein (PrPTSE), the probable etiological agent of the transmissible spongiform encephalopathies (TSEs), is resistant to degradation and can persist in the environment. Lichens, mutualistic symbioses containing fungi, algae, bacteria and occasionally cyanobacteria, are ubiquitous in the environment and have evolved unique biological activities allowing their survival in challenging ecological niches. We investigated PrPTSE inactivation by lichens and found acetone extracts of three lichen species (Parmelia sulcata, Cladonia rangiferina and Lobaria pulmonaria) have the ability to degrade prion protein (PrP) from TSE-infected hamsters, mice and deer. Immunoblots measuring PrP levels and protein misfolding cyclic amplification indicated at least two logs of reductions in PrPTSE. Degradative activity was not found in closely related lichen species or in algae or a cyanobacterium that inhabit lichens. Degradation was blocked by Pefabloc SC, a serine protease inhibitor, but not inhibitors of other proteases or enzymes. Additionally, we found that PrP levels in PrPTSE-enriched preps or infected brain homogenates are also reduced following exposure to freshly-collected P. sulcata or an aqueous extract of the lichen. Our findings indicate that these lichen extracts efficiently degrade PrPTSE and suggest that some lichens could have potential to inactivate TSE infectivity on the landscape or be a source for agents to degrade prions. Further work to clone and characterize the protease, assess its effect on TSE infectivity and determine which organism or organisms present in lichens produce or influence the protease activity is warranted.

Johnson, C. J.; Bennett, J. P.; Biro, S. M.; Duque-Velasquez, J. C.; Rodriguez, C. M.; Bessen, R. A.; Rocke, T. E.

2011-01-01

377

Latent Periodicity of Protein Sequences  

Microsoft Academic Search

This article is in the area of protein sequence investigation. It studies protein sequence periodicity. The notion of latent periodicity is introduced. A mathematical method for searching for latent periodicity in protein sequences is developed. Implementation of the method developed for known cases of perfect and imperfect periodicity is demonstrated. Latent periodicity of many protein sequences from the SWISS-PROT data

Maria A. Korotkova; Eugene V. Korotkov; Valentina M. Rudenko

1999-01-01

378

Energy Landscape of the Prion Protein Helix 1 Probed by Metadynamics and NMR  

PubMed Central

The characterization of the structural dynamics of proteins, including those that present a substantial degree of disorder, is currently a major scientific challenge. These dynamics are biologically relevant and govern the majority of functional and pathological processes. We exploited a combination of enhanced molecular simulations of metadynamics and NMR measurements to study heterogeneous states of proteins and peptides. In this way, we determined the structural ensemble and free-energy landscape of the highly dynamic helix 1 of the prion protein (PrP-H1), whose misfolding and aggregation are intimately connected to a group of neurodegenerative disorders known as transmissible spongiform encephalopathies. Our combined approach allowed us to dissect the factors that govern the conformational states of PrP-H1 in solution, and the implications of these factors for prion protein misfolding and aggregation. The results underline the importance of adopting novel integrated approaches that take advantage of experiments and theory to achieve a comprehensive characterization of the structure and dynamics of biological macromolecules.

Camilloni, Carlo; Schaal, Daniel; Schweimer, Kristian; Schwarzinger, Stephan; De Simone, Alfonso

2012-01-01

379

Huntingtin toxicity in yeast model depends on polyglutamine aggregation mediated by a prion-like protein Rnq1  

PubMed Central

The cause of Huntington's disease is expansion of polyglutamine (polyQ) domain in huntingtin, which makes this protein both neurotoxic and aggregation prone. Here we developed the first yeast model, which establishes a direct link between aggregation of expanded polyQ domain and its cytotoxicity. Our data indicated that deficiencies in molecular chaperones Sis1 and Hsp104 inhibited seeding of polyQ aggregates, whereas ssa1, ssa2, and ydj1–151 mutations inhibited expansion of aggregates. The latter three mutants strongly suppressed the polyQ toxicity. Spontaneous mutants with suppressed aggregation appeared with high frequency, and in all of them the toxicity was relieved. Aggregation defects in these mutants and in sis1–85 were not complemented in the cross to the hsp104 mutant, demonstrating an unusual type of inheritance. Since Hsp104 is required for prion maintenance in yeast, this suggested a role for prions in polyQ aggregation and toxicity. We screened a set of deletions of nonessential genes coding for known prions and related proteins and found that deletion of the RNQ1 gene specifically suppressed aggregation and toxicity of polyQ. Curing of the prion form of Rnq1 from wild-type cells dramatically suppressed both aggregation and toxicity of polyQ. We concluded that aggregation of polyQ is critical for its toxicity and that Rnq1 in its prion conformation plays an essential role in polyQ aggregation leading to the toxicity.

Meriin, Anatoli B.; Zhang, Xiaoqian; He, Xiangwei; Newnam, Gary P.; Chernoff, Yury O.; Sherman, Michael Y.

2002-01-01

380

Methionine oxidation of Sup35 protein induces formation of the [PSI+] prion in a yeast peroxiredoxin mutant.  

PubMed

The frequency with which the yeast [PSI(+)] prion form of Sup35 arises de novo is controlled by a number of genetic and environmental factors. We have previously shown that in cells lacking the antioxidant peroxiredoxin proteins Tsa1 and Tsa2, the frequency of de novo formation of [PSI(+)] is greatly elevated. We show here that Tsa1/Tsa2 also function to suppress the formation of the [PIN(+)] prion form of Rnq1. However, although oxidative stress increases the de novo formation of both [PIN(+)] and [PSI(+)], it does not overcome the requirement of cells being [PIN(+)] to form the [PSI(+)] prion. We use an anti-methionine sulfoxide antibody to show that methionine oxidation is elevated in Sup35 during oxidative stress conditions. Abrogating Sup35 methionine oxidation by overexpressing methionine sulfoxide reductase (MSRA) prevents [PSI(+)] formation, indicating that Sup35 oxidation may underlie the switch from a soluble to an aggregated form of Sup35. In contrast, we were unable to detect methionine oxidation of Rnq1, and MSRA overexpression did not affect [PIN(+)] formation in a tsa1 tsa2 mutant. The molecular basis of how yeast and mammalian prions form infectious amyloid-like structures de novo is poorly understood. Our data suggest a causal link between Sup35 protein oxidation and de novo [PSI(+)] prion formation. PMID:21832086

Sideri, Theodora C; Koloteva-Levine, Nadejda; Tuite, Mick F; Grant, Chris M

2011-08-09

381

[Prion diseases].  

PubMed

Prion diseases are a family of progressive neurodegenerative disorders caused by prions. There are four human prion diseases: Creutzfeldt-Jakob disease, Gerstmann-Straussler-Scheinker syndrome, fatal insomnia and Kuru. They can arise in three different ways: acquired, familial or sporadic. We review clinical presentations, pathophysiology, morphological picture, diagnostic procedures and available treatment options of prion diseases. PMID:23235426

Sto?da, N I; Zavalishin, I A

2012-01-01

382

Identification and structural analysis of C-terminally truncated collapsin response mediator protein-2 in a murine model of prion diseases  

PubMed Central

Background Prion diseases are fatal neurodegenerative disorders that accompany an accumulation of the disease-associated form(s) of prion protein (PrPSc) in the central nervous system. The neuropathological changes in the brain begin with focal deposits of PrPSc, followed by pathomorphological abnormalities of axon terminal degeneration, synaptic loss, atrophy of dendritic trees, and eventual neuronal cell death in the lesions. However, the underlying molecular basis for these neuropathogenic abnormalities is not fully understood. Results In a proteomic analysis of soluble proteins in the brains of mice challenged intracerebrally with scrapie prion (Obihiro I strain), we found that the amount of the full-length form of collapsin response mediator protein-2 (CRMP-2; 61 kDa) decreased in the late stages of the disease, while the amount of its truncated form (56 kDa) increased to comparable levels observed for the full-length form. Detailed analysis by liquid chromatography-electrospray ionization-tandem mass spectrometry showed that the 56-kDa form (named CRMP-2-?C) lacked the sequence from serine518 to the C-terminus, including the C-terminal phosphorylation sites important for the regulation of axonal growth and axon-dendrite specification in developing neurons. The invariable size of the mRNA transcript in Northern blot analysis suggested that the truncation was due to post-translational proteolysis. By overexpression of CRMP-2-?C in primary cultured neurons, we observed the augmentation of the development of neurite branch tips to the same levels as for CRMP-2T514A/T555A, a non-phosphorylated mimic of the full-length protein. This suggests that the increased level of CRMP-2-?C in the brain modulates the integrity of neurons, and may be involved in the pathogenesis of the neuronal abnormalities observed in the late stages of the disease. Conclusions We identified the presence of CRMP-2-?C in the brain of a murine model of prion disease. Of note, C-terminal truncations of CRMP-2 have been recently observed in models for neurodegenerative disorders such as ischemia, traumatic brain injury, and Wallerian degeneration. While the structural identity of CRMP-2-?C in those models remains unknown, the present study should provide clues to the molecular pathology of degenerating neurons in prion diseases in connection with other neurodegenerative disorders.

2010-01-01

383

Non-infectious aggregates of the prion protein react with several PrPSc-directed antibodies.  

PubMed

The key event in the pathogenesis of prion diseases is the conformational conversion of the normal prion protein (PrP) (PrP(C)) into an infectious, aggregated isoform (PrP(Sc)) that has a high content of beta-sheet. Historically, a great deal of effort has been devoted to developing antibodies that specifically recognize PrP(Sc) but not PrP(C), as such antibodies would have enormous diagnostic and experimental value. A mouse monoclonal IgM antibody (designated 15B3) and three PrP motif-grafted monoclonal antibodies (referred to as IgG 19-33, 89-112, and 136-158) have been previously reported to react specifically with infectious PrP(Sc) but not PrP(C). In this study, we extend the characterization of these four antibodies by testing their ability to immunoprecipitate and immunostain infectious and non-infectious aggregates of wild-type, mutant, and recombinant PrP. We find that 15B3 as well as the motif-grafted antibodies recognize multiple types of aggregated PrP, both infectious and non-infectious, including forms found in brain, in transfected cells, and induced in vitro from purified recombinant protein. These antibodies are exquisitely selective for aggregated PrP, and do not react with soluble PrP even when present in vast excess. Our results suggest that 15B3 and the motif-grafted antibodies recognize structural features common to both infectious and non-infectious aggregates of PrP. Our study extends the utility of these antibodies for diagnostic and experimental purposes, and it provides new insight into the structural changes that accompany PrP oligomerization and prion propagation. PMID:18298665

Biasini, Emiliano; Seegulam, M Esa; Patti, Brianna N; Solforosi, Laura; Medrano, Andrea Z; Christensen, Heather M; Senatore, Assunta; Chiesa, Roberto; Williamson, R Anthony; Harris, David A

2008-06-01

384

Selective amplification of classical and atypical prions using modified protein misfolding cyclic amplification.  

PubMed

With the development of protein misfolding cyclic amplification (PMCA), the topic of faithful propagation of prion strain-specific structures has been constantly debated. Here we show that by subjecting brain material of a synthetic strain consisting of a mixture of self-replicating states to PMCAb, selective amplification of PrP(Sc) could be achieved, and that PMCAb mimicked the evolutionary trend observed during serial transmission in animals. On the other hand, using modified PMCAb conditions that employ partially deglycosylated PrP(C) (dgPMCAb), an alternative transmissible state referred to as atypical protease-resistant form of the prion protein (atypical PrPres) was selectively amplified from a mixture. Surprisingly, when hamster-adapted strains (263K and Hyper) were subjected to dgPMCAb, their proteinase K digestion profile underwent a dramatic transformation, suggesting that a mixture of atypical PrPres and PrP(Sc) might be present in brain-derived materials. However, detailed analysis revealed that the proteinase K-resistant profile of PrP(Sc) changed in response to dgPMCAb. Despite these changes, the 263K strain-specific disease phenotype was preserved after passage through dgPMCAb. This study revealed that the change in PrP(Sc) biochemical phenotype does not always represent an irreversible transformation of a strain, but rather demonstrated the existence of a wide range of variation for strain-specific physical features in response to a change in prion replication environment. The current work introduced a new PMCA technique for amplification of atypical PrPres and raised a number of questions about the need for a clever distinction between actual strain mutation and variation of strain-specific features in response to a change in the replication environment. PMID:23168413

Makarava, Natallia; Savtchenko, Regina; Baskakov, Ilia V

2012-11-20

385

Comparison of the local structural stabilities of mammalian prion protein (PrP) by fragment molecular orbital calculations  

PubMed Central

Bovine spongiform encephalopathy (BSE), a member of the prion diseases, is a fatal neurodegenerative disorder suspected to be caused by a malfunction of prion protein (PrP). Although BSE prions have been reported to be transmitted to a wide range of animal species, dogs and hamsters are known to be BSE-resistant animals. Analysis of canine and hamster PrP could elucidate the molecular mechanisms supporting the species barriers to BSE prion transmission. The structural stability of 6 mammalian PrPs, including human, cattle, mouse, hamster, dog and cat, was analyzed. We then evaluated intramolecular interactions in PrP by fragment molecular orbital (FMO) calculations. Despite similar backbone structures, the PrP side-chain orientations differed among the animal species examined. The pair interaction energies between secondary structural elements in the PrPs varied considerably, indicating that the local structural stabilities of PrP varied among the different animal species. Principal component analysis (PCA) demonstrated that different local structural stability exists in bovine PrP compared with the PrP of other animal species examined. The results of the present study suggest that differences in local structural stabilities between canine and bovine PrP link diversity in susceptibility to BSE prion infection.

Hasegawa, Koji; Mohri, Shirou; Yokoyama, Takashi

2013-01-01

386

Prion neurodegeneration  

PubMed Central

Synaptic dysfunction is a key process in the evolution of many neurodegenerative diseases, with synaptic loss preceding that of neuronal cell bodies. In Alzheimer, Huntington, and prion diseases early synaptic changes correlate with cognitive and motor decline, and altered synaptic function may also underlie deficits in a number of psychiatric and neurodevelopmental conditions. The formation, remodelling and elimination of spines and synapses are continual physiological processes, moulding cortical architecture, underpinning the abilities to learn and remember. In disease, however, particularly in protein misfolding neurodegenerative disorders, lost synapses are not replaced and this loss is followed by neuronal death. These two processes are separately regulated, with mechanistic, spatial and temporal segregation of the death ‘routines’ of synapses and cell bodies. Recent insights into the reversibility of synaptic dysfunction in a mouse model of prion disease at neurophysiological, behavioral and morphological levels call for a deeper analysis of the mechanisms underlying neurotoxicity at the synapse, and have important implications for therapy of prion and other neurodegenerative disorders.

2009-01-01

387

Prion Protein Misfolding Affects Calcium Homeostasis and Sensitizes Cells to Endoplasmic Reticulum Stress  

PubMed Central

Prion-related disorders (PrDs) are fatal neurodegenerative disorders characterized by progressive neuronal impairment as well as the accumulation of an abnormally folded and protease resistant form of the cellular prion protein, termed PrPRES. Altered endoplasmic reticulum (ER) homeostasis is associated with the occurrence of neurodegeneration in sporadic, infectious and familial forms of PrDs. The ER operates as a major intracellular calcium store, playing a crucial role in pathological events related to neuronal dysfunction and death. Here we investigated the possible impact of PrP misfolding on ER calcium homeostasis in infectious and familial models of PrDs. Neuro2A cells chronically infected with scrapie prions showed decreased ER-calcium content that correlated with a stronger upregulation of UPR-inducible chaperones, and a higher sensitivity to ER stress-induced cell death. Overexpression of the calcium pump SERCA stimulated calcium release and increased the neurotoxicity observed after exposure of cells to brain-derived infectious PrPRES. Furthermore, expression of PrP mutants that cause hereditary Creutzfeldt-Jakob disease or fatal familial insomnia led to accumulation of PrPRES and their partial retention at the ER, associated with a drastic decrease of ER calcium content and higher susceptibility to ER stress. Finally, similar results were observed when a transmembrane form of PrP was expressed, which is proposed as a neurotoxic intermediate. Our results suggest that alterations in calcium homeostasis and increased susceptibility to ER stress are common pathological features of both infectious and familial PrD models.

Torres, Mauricio; Castillo, Karen; Armisen, Ricardo; Stutzin, Andres; Soto, Claudio; Hetz, Claudio

2010-01-01

388

Prion protein misfolding affects calcium homeostasis and sensitizes cells to endoplasmic reticulum stress.  

PubMed

Prion-related disorders (PrDs) are fatal neurodegenerative disorders characterized by progressive neuronal impairment as well as the accumulation of an abnormally folded and protease resistant form of the cellular prion protein, termed PrP(RES). Altered endoplasmic reticulum (ER) homeostasis is associated with the occurrence of neurodegeneration in sporadic, infectious and familial forms of PrDs. The ER operates as a major intracellular calcium store, playing a crucial role in pathological events related to neuronal dysfunction and death. Here we investigated the possible impact of PrP misfolding on ER calcium homeostasis in infectious and familial models of PrDs. Neuro2A cells chronically infected with scrapie prions showed decreased ER-calcium content that correlated with a stronger upregulation of UPR-inducible chaperones, and a higher sensitivity to ER stress-induced cell death. Overexpression of the calcium pump SERCA stimulated calcium release and increased the neurotoxicity observed after exposure of cells to brain-derived infectious PrP(RES). Furthermore, expression of PrP mutants that cause hereditary Creutzfeldt-Jakob disease or fatal familial insomnia led to accumulation of PrP(RES) and their partial retention at the ER, associated with a drastic decrease of ER calcium content and higher susceptibility to ER stress. Finally, similar results were observed when a transmembrane form of PrP was expressed, which is proposed as a neurotoxic intermediate. Our results suggest that alterations in calcium homeostasis and increased susceptibility to ER stress are common pathological features of both infectious and familial PrD models. PMID:21209925

Torres, Mauricio; Castillo, Karen; Armisén, Ricardo; Stutzin, Andrés; Soto, Claudio; Hetz, Claudio

2010-12-29

389

Degradation of scrapie associated prion protein (PrPSc) by the gastrointestinal microbiota of cattle.  

PubMed

A food-borne origin of the transmission of bovine spongiform encephalopathy (BSE) to cattle is commonly assumed. However, the fate of infectious prion protein during polygastric digestion remains unclear. It is unknown at present, whether infectious prion proteins, considered to be very stable, are degraded or inactivated by microbial processes in the gastrointestinal tract of cattle. In this study, rumen and colon contents from healthy cattle, taken immediately after slaughter, were used to assess the ability of these microbial consortia to degrade PrP(Sc). Therefore, the consortia were incubated with brain homogenates of scrapie (strain 263K) infected hamsters under physiological anaerobic conditions at 37 degrees C. Within 20 h, PrP(Sc) was digested both with ruminal and colonic microbiota up to immunochemically undetectable levels. Especially polymyxin resistant (mainly gram-positive) bacteria expressed PrP(Sc) degrading activity. These data demonstrate the ability of bovine gastrointestinal microbiota to degrade PrP(Sc) during digestion. PMID:16820134

Scherbel, Christina; Pichner, Rohtraud; Groschup, Martin H; Mueller-Hellwig, Simone; Scherer, Siegfried; Dietrich, Richard; Maertlbauer, Erwin; Gareis, Manfred

2006-07-06

390

High incidence of single nucleotide polymorphisms in the prion protein gene of native Brazilian Caracu cattle.  

PubMed

Different alleles of the human and ovine prion protein gene correlate with a varying susceptibility to transmissible spongiform encephalopathies. However, the pathogenic implications of specific polymorphisms in the bovine prion protein gene (PRNP) are only poorly understood. Previous studies on the bovine PRNP gene investigated common European and North American cattle breeds. As a consequence of decades of intensive breeding for specific traits, these modern breeds represent only a small fraction of the bovine gene pool. In this study, we analysed PRNP polymorphisms in the native Brazilian Caracu breed, which developed in geographical isolation since the 16th century. A total of 10 single nucleotide polymorphisms (SNPs) were discovered in the coding region of the Caracu PRNP gene. Eight of the SNPs occurred at high frequencies in Caracu cattle (variant allele frequencies = 0.10-0.76), but were absent or only rarely observed in European and North American breeds. One of the Caracu SNPs was associated with an amino acid exchange from serine to asparagine (f = 0.17). This SNP was not detected in Holstein-Friesian, Simmental and German Gelbvieh and was only rarely detected in beef cattle (f = 0.01). We found 17 haplotypes for PRNP in the Caracu breed. PMID:16965405

Kues, W A; Ollhoff, R D; Carnwath, J W; de Souza, F P; Madeira, H M F; Niemann, H

2006-10-01

391

Methionine oxidation perturbs the structural core of the prion protein and suggests a generic misfolding pathway.  

PubMed

Oxidative stress and misfolding of the prion protein (PrP(C)) are fundamental to prion diseases. We have therefore probed the effect of oxidation on the structure and stability of PrP(C). Urea unfolding studies indicate that H(2)O(2) oxidation reduces the thermodynamic stability of PrP(C) by as much as 9 kJ/mol. (1)H-(15)N NMR studies indicate methionine oxidation perturbs key hydrophobic residues on one face of helix-C as follows: Met-205, Val-209, and Met-212 together with residues Val-160 and Tyr-156. These hydrophobic residues pack together and form the structured core of the protein, stabilizing its ternary structure. Copper-catalyzed oxidation of PrP(C) causes a more significant alteration of the structure, generating a monomeric molten globule species that retains its native helical content. Further copper-catalyzed oxidation promotes extended ?-strand structures that lack a cooperative fold. This transition from the helical molten globule to ?-conformation has striking similarities to a misfolding intermediate generated at low pH. PrP may therefore share a generic misfolding pathway to amyloid fibers, irrespective of the conditions promoting misfolding. Our observations support the hypothesis that oxidation of PrP destabilizes the native fold of PrP(C), facilitating the transition to PrP(Sc). This study gives a structural and thermodynamic explanation for the high levels of oxidized methionine in scrapie isolates. PMID:22654104

Younan, Nadine D; Nadal, Rebecca C; Davies, Paul; Brown, David R; Viles, John H

2012-05-31

392

Conformational detection of prion protein with biarsenical labeling and FlAsH fluorescence  

SciTech Connect

Prion diseases are associated with the misfolding of the host-encoded cellular prion protein (PrP{sup C}) into a disease associated form (PrP{sup Sc}). Recombinant PrP can be refolded into either an {alpha}-helical rich conformation ({alpha}-PrP) resembling PrP{sup C} or a {beta}-sheet rich, protease resistant form similar to PrP{sup Sc}. Here, we generated tetracysteine tagged recombinant PrP, folded this into {alpha}- or {beta}-PrP and determined the levels of FlAsH fluorescence. Insertion of the tetracysteine tag at three different sites within the 91-111 epitope readily distinguished {beta}-PrP from {alpha}-PrP upon FlAsH labeling. Labelling of tetracysteine tagged PrP in the {alpha}-helical form showed minimal fluorescence, whereas labeling of tagged PrP in the {beta}-sheet form showed high fluorescence indicating that this region is exposed upon conversion. This highlights a region of PrP that can be implicated in the development of diagnostics and is a novel, protease free mechanism for distinguishing PrP{sup Sc} from PrP{sup C}. This technique may also be applied to any protein that undergoes conformational change and/or misfolding such as those involved in other neurodegenerative disorders including Alzheimer's, Huntington's and Parkinson's diseases.

Coleman, Bradley M. [Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010 (Australia); Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Nisbet, Rebecca M.; Han, Sen [Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010 (Australia); Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Department of Pathology and Mental Health Research Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Cappai, Roberto [Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Department of Pathology and Mental Health Research Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Hatters, Danny M. [Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010 (Australia); Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Department of Pathology and Mental Health Research Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Hill, Andrew F. [Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010 (Australia); Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010 (Australia); Department of Pathology and Mental Health Research Institute, University of Melbourne, Parkville, Victoria 3010 (Australia)], E-mail: a.hill@unimelb.edu.au

2009-03-13

393

The cellular prion protein traps Alzheimer's A? in an oligomeric form and disassembles amyloid fibers  

PubMed Central

There is now strong evidence to show that the presence of the cellular prion protein (PrPC) mediates amyloid-? (A?) neurotoxicity in Alzheimer's disease (AD). Here, we probe the molecular details of the interaction between PrPC and A? and discover that substoichiometric amounts of PrPC, as little as 1/20, relative to A? will strongly inhibit amyloid fibril formation. This effect is specific to the unstructured N-terminal domain of PrPC. Electron microscopy indicates PrPC is able to trap A? in an oligomeric form. Unlike fibers, this oligomeric A? contains antiparallel ? sheet and binds to a oligomer specific conformational antibody. Our NMR studies show that a specific region of PrPC, notably residues 95–113, binds to A? oligomers, but only once A? misfolds. The ability of PrPC to trap and concentrate A? in an oligomeric form and disassemble mature fibers suggests a mechanism by which PrPC might confer A? toxicity in AD, as oligomers are thought to be the toxic form of A?. Identification of a specific recognition site on PrPC that traps A? in an oligomeric form is potentially a therapeutic target for the treatment of Alzheimer's disease.—Younan, N. D., Sarell, C. J., Davies, P., Brown, D. R., Viles, J. H. The cellular prion protein traps Alzheimer's A? in an oligomeric form and disassembles amyloid fibers.

Younan, Nadine D.; Sarell, Claire J.; Davies, Paul; Brown, David R.; Viles, John H.

2013-01-01

394

Therapy for prion diseases  

PubMed Central

Insights into the molecular basis and the temporal evolution of neurotoxicity in prion disease are increasing, and recent work in mice leads to new avenues for targeting treatment of these disorders. Using lentivirally mediated RNA interference (RNAi) against native prion protein (PrP), White et al. report the first therapeutic intervention that results in neuronal rescue, prevents symptoms and increases survival in mice with established prion disease.1 Both the target and the timing of treatment here are crucial to the effectiveness of this strategy: the formation of the neurotoxic prion agent is prevented at a point when diseased neurons can still be saved from death. But the data also give new insights into the timing of treatment in the context of the pattern of spread of prion infection throughout the brain, with implications for developing the most effective treatments.

White, Melanie D

2009-01-01

395

The Rich Electrochemistry and Redox Reactions of the Copper Sites in the Cellular Prion Protein  

PubMed Central

This paper reviews recent electrochemical studies of the copper complexes of prion protein (PrP) and its related peptides, and correlates their redox behavior to chemical and biologically relevant reactions. Particular emphasis is placed on the difference in redox properties between copper in the octarepeat (OR) and the non-OR domains of PrP, as well as differences between the high and low copper occupancy states in the OR domain. Several discrepancies in literature concerning these differences are discussed and reconciled. The PrP copper complexes, in comparison to copper complexes of other amyloidogenic proteins/peptides, display a more diverse and richer redox chemistry. The specific protocols and caveats that need to be considered in studying the electrochemistry and redox reactions of copper complexes of PrP, PrP-derived peptides, and other related amyloidogenic proteins are summarized.

Zhou, Feimeng; Millhauser, Glenn L.

2012-01-01

396

Different Behavior toward Bovine Spongiform Encephalopathy Infection of Bovine Prion Protein Transgenic Mice with One Extra Repeat Octapeptide Insert Mutation  

Microsoft Academic Search

In humans, insert mutations within the repetitive octapeptide region of the prion protein gene (Prnp) are often associated with familial spongiform encephalopathies. In this study, transgenic mice expressing bovine PrP (boTg mice) bearing an additional octapeptide insertion to the wild type (seven octapeptide repeats instead of six) showed an altered course of bovine spongiform encephalopathy (BSE) infection, reflected as reduced

J. Castilla; A. Gutierrez-Adan; A. Brun; B. Pintado; B. Parra; M. A. Ramirez; F. J. Salguero; F. Diaz San Segundo; A. Rabano; M. J. Cano; J. M. Torres

2004-01-01