1
|
Silva CJ, Cassmann ED, Greenlee JJ, Erickson-Beltran ML, Requena JR. A Mass Spectrometry-Based Method of Quantifying the Contribution of the Lysine Polymorphism at Position 171 in Sheep PrP. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:245-254. [PMID: 36622794 PMCID: PMC9897214 DOI: 10.1021/jasms.2c00277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 12/15/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
In sheep, the transmissibility and progression of scrapie, a sheep prion (PrPSc) disease, is strongly dependent upon specific amino acid polymorphisms in the natively expressed prion protein (PrPC). Sheep expressing PrPC with lysine (K) polymorphism at position 171 (K171) are partially resistant to oronasal dosing of classical sheep scrapie. In addition, scrapie infected sheep expressing the K171 polymorphism show a longer incubation period compared to sheep homozygous (glutamine (Q)) at position 171. Quantitating the amount of the K171 polymorphism in a sheep scrapie sample can provide important information on the composition of PrPSc. A tryptic peptide, 159R.YPNQVYYRPVDK.Y172, derived from the digestion of 171K recombinant PrP, was identified as an analyte peptide suitable for a multiple reaction monitoring-based analysis. This method, using 15N-labeled analogs and another internal peptide from the proteinase K-resistant core, permits the simultaneous quantitation of the total amount of PrP and the proportion of K171 polymorphism in the sample. Background molecules with similar retention times and transitions were present in samples from scrapie-infected sheep. Proteinase K digestion followed by ultracentrifugation-based isolation or phosphotungstic acid-based isolation were employed to minimize the contribution of those background molecules, making this approach suitable for quantitating the amount of the K171 polymorphism in heterozygous scrapie infected sheep.
Collapse
Affiliation(s)
- Christopher J. Silva
- Produce
Safety and Microbiology Research Unit, Western Regional Research Center,
United States Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California 94710, United States of America
| | - Eric D. Cassmann
- Virus
and Prion Research Unit, National Animal Disease Center, Agricultural
Research Service, United States Department
of Agriculture, Ames, Iowa 50010, United
States of America
| | - Justin J. Greenlee
- Virus
and Prion Research Unit, National Animal Disease Center, Agricultural
Research Service, United States Department
of Agriculture, Ames, Iowa 50010, United
States of America
| | - Melissa L. Erickson-Beltran
- Produce
Safety and Microbiology Research Unit, Western Regional Research Center,
United States Department of Agriculture, Agricultural Research Service, 800 Buchanan Street, Albany, California 94710, United States of America
| | - Jésus R. Requena
- CIMUS
Biomedical Research Institute & Department of Medical Sciences, University of Santiago de Compostela−IDIS, 15782 Santiago
de Compostela, Spain
| |
Collapse
|
2
|
Vidal E, Sánchez-Martín MA, Eraña H, Lázaro SP, Pérez-Castro MA, Otero A, Charco JM, Marín B, López-Moreno R, Díaz-Domínguez CM, Geijo M, Ordóñez M, Cantero G, di Bari M, Lorenzo NL, Pirisinu L, d’Agostino C, Torres JM, Béringue V, Telling G, Badiola JJ, Pumarola M, Bolea R, Nonno R, Requena JR, Castilla J. Bona fide atypical scrapie faithfully reproduced for the first time in a rodent model. Acta Neuropathol Commun 2022; 10:179. [PMID: 36514160 PMCID: PMC9749341 DOI: 10.1186/s40478-022-01477-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 11/10/2022] [Indexed: 12/15/2022] Open
Abstract
Atypical Scrapie, which is not linked to epidemics, is assumed to be an idiopathic spontaneous prion disease in small ruminants. Therefore, its occurrence is unlikely to be controlled through selective breeding or other strategies as it is done for classical scrapie outbreaks. Its spontaneous nature and its sporadic incidence worldwide is reminiscent of the incidence of idiopathic spontaneous prion diseases in humans, which account for more than 85% of the cases in humans. Hence, developing animal models that consistently reproduce this phenomenon of spontaneous PrP misfolding, is of importance to study the pathobiology of idiopathic spontaneous prion disorders. Transgenic mice overexpressing sheep PrPC with I112 polymorphism (TgShI112, 1-2 × PrP levels compared to sheep brain) manifest clinical signs of a spongiform encephalopathy spontaneously as early as 380 days of age. The brains of these animals show the neuropathological hallmarks of prion disease and biochemical analyses of the misfolded prion protein show a ladder-like PrPres pattern with a predominant 7-10 kDa band. Brain homogenates from spontaneously diseased transgenic mice were inoculated in several models to assess their transmissibility and characterize the prion strain generated: TgShI112 (ovine I112 ARQ PrPC), Tg338 (ovine VRQ PrPC), Tg501 (ovine ARQ PrPC), Tg340 (human M129 PrPC), Tg361 (human V129 PrPC), TgVole (bank vole I109 PrPC), bank vole (I109I PrPC), and sheep (AHQ/ARR and AHQ/AHQ churra-tensina breeds). Our analysis of the results of these bioassays concludes that the strain generated in this model is indistinguishable to that causing atypical scrapie (Nor98). Thus, we present the first faithful model for a bona fide, transmissible, ovine, atypical scrapie prion disease.
Collapse
Affiliation(s)
- Enric Vidal
- grid.424716.2Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain ,grid.424716.2IRTA Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain
| | - Manuel A. Sánchez-Martín
- grid.11762.330000 0001 2180 1817Transgenic Facility. Department of Medicine, University of Salamanca, 37007 Salamanca, Spain
| | - Hasier Eraña
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain ,ATLAS Molecular Pharma S. L., Derio, Bizkaia Spain ,grid.413448.e0000 0000 9314 1427Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Sonia Pérez Lázaro
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Miguel A. Pérez-Castro
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain
| | - Alicia Otero
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Jorge M. Charco
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain ,ATLAS Molecular Pharma S. L., Derio, Bizkaia Spain ,grid.413448.e0000 0000 9314 1427Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Belén Marín
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Rafael López-Moreno
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain
| | - Carlos M. Díaz-Domínguez
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain
| | - Mariví Geijo
- grid.509696.50000 0000 9853 6743Animal Health Department, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Montserrat Ordóñez
- grid.424716.2Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain ,grid.424716.2IRTA Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain
| | - Guillermo Cantero
- grid.424716.2Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain ,grid.424716.2IRTA Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain
| | - Michele di Bari
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Nuria L. Lorenzo
- grid.11794.3a0000000109410645CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago, Spain
| | - Laura Pirisinu
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Claudia d’Agostino
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Juan María Torres
- grid.419190.40000 0001 2300 669XCentro de Investigación en Sanidad Animal (CISA), Centro Superior de Investigaciones Científicas (CSIC) Valdeolmos, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), 28130 Madrid, Spain
| | - Vincent Béringue
- grid.417961.cMolecular Virology and Immunology, Institut National de La Recherche Agronomique (INRA), Université Paris-Saclay, Jouy-en-Josas, France
| | - Glenn Telling
- grid.47894.360000 0004 1936 8083Prion Research Center (PRC) and the Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO USA
| | - Juan J. Badiola
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Martí Pumarola
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Campus de UAB, Bellaterra, 08193 Barcelona, Catalonia Spain
| | - Rosa Bolea
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Romolo Nonno
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Jesús R. Requena
- grid.11794.3a0000000109410645CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago, Spain
| | - Joaquín Castilla
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain ,grid.413448.e0000 0000 9314 1427Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain ,grid.424810.b0000 0004 0467 2314IKERBASQUE, Basque Foundation for Science, Bilbao, Bizkaia Spain
| |
Collapse
|
3
|
Pineau H, Sim VL. From Cell Culture to Organoids-Model Systems for Investigating Prion Strain Characteristics. Biomolecules 2021; 11:biom11010106. [PMID: 33466947 PMCID: PMC7830147 DOI: 10.3390/biom11010106] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 02/06/2023] Open
Abstract
Prion diseases are the hallmark protein folding neurodegenerative disease. Their transmissible nature has allowed for the development of many different cellular models of disease where prion propagation and sometimes pathology can be induced. This review examines the range of simple cell cultures to more complex neurospheres, organoid, and organotypic slice cultures that have been used to study prion disease pathogenesis and to test therapeutics. We highlight the advantages and disadvantages of each system, giving special consideration to the importance of strains when choosing a model and when interpreting results, as not all systems propagate all strains, and in some cases, the technique used, or treatment applied, can alter the very strain properties being studied.
Collapse
Affiliation(s)
- Hailey Pineau
- Department of Medicine, University of Alberta, Edmonton, AB T6G 2B7, Canada;
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Valerie L. Sim
- Department of Medicine, University of Alberta, Edmonton, AB T6G 2B7, Canada;
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2R3, Canada
- Correspondence:
| |
Collapse
|
4
|
Yaman Y, Şenlik B, Özüiçli M, Keleş M, Aymaz R, Bay V, Hatipoğlu E, Koncagül S, Öner Y, Ün C. Detecting fecal egg count (FEC) for gastrointestinal nematodes of adult Turkish sheep with different scrapie related PRNP haplotypes. Anim Biotechnol 2020; 32:381-387. [PMID: 33356831 DOI: 10.1080/10495398.2020.1862136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Scrapie is a transmissible spongiform encephalopathy caused by prions and leads to neurodegeneration in the Central Nervous System (CNS) of sheep and goats. Genetic resistance/susceptibility to scrapie is well studied and it is known that the variations of 136th, 154th and 171st codons at the ovine PRNP gene have a major effect on the development of the disease. Many studies demonstrated that selection for PRNP genotypes has not influenced other performance traits, nevertheless, there is a knowledge gap about the possible link between the PRNP gene and the status of the other important diseases that affect the sheep population worldwide. In the present study, we tested whether there is an association between scrapie-related PRNP genotypes and fecal egg count (FEC) of gastrointestinal nematodes in seven adult Turkish sheep breeds. For this purpose, FEC scores of studied sheep (n = 253) were determined and the same animals were genotyped for the PRNP gene. Finally, an association analysis was performed for scrapie resistant (ARR), susceptible (VRQ), and wild-type (ARQ) haplotypes. Based on our statistical analysis, it is concluded that PRNP genotypes have no positive or negative effect on the FEC scores of adult sheep.
Collapse
Affiliation(s)
- Yalçın Yaman
- Department of Biometry and Genetics, Sheep Breeding and Research Institute, Bandirma, Turkey
| | - Bayram Şenlik
- Veterinary Faculty, Department of Parasitology, Uludag University, Bursa, Turkey
| | - Mehmet Özüiçli
- Veterinary Faculty, Department of Parasitology, Uludag University, Bursa, Turkey
| | - Murat Keleş
- Department of Biometry and Genetics, Sheep Breeding and Research Institute, Bandirma, Turkey
| | - Ramazan Aymaz
- Department of Biometry and Genetics, Sheep Breeding and Research Institute, Bandirma, Turkey
| | - Veysel Bay
- Department of Biometry and Genetics, Sheep Breeding and Research Institute, Bandirma, Turkey
| | - Ecem Hatipoğlu
- Department of Biometry and Genetics, Sheep Breeding and Research Institute, Bandirma, Turkey
| | - Seyrani Koncagül
- Agricultural Faculty, Departments of Animal Science, Ankara University, Ankara, Turkey
| | - Yasemin Öner
- Agricultural Faculty, Department of Biometry and Genetics, Uludag University, Bursa, Turkey
| | - Cemal Ün
- Faculty of Science, Department of Biology, Ege University, İzmir, Turkey
| |
Collapse
|
5
|
Abstract
In sheep, scrapie is a fatal neurologic disease that is caused by a misfolded protein called a prion (designated PrPSc). The normal cellular prion protein (PrPC) is encoded by an endogenous gene, PRNP, that is present in high concentrations within the CNS. Although a broad range of functions has been described for PrPC, its entire range of functions has yet to be fully elucidated. Accumulation of PrPSc results in neurodegeneration. The PRNP gene has several naturally occurring polymorphisms, and there is a strong correlation between scrapie susceptibility and PRNP genotype. The cornerstone of scrapie eradication programs is the selection of scrapie-resistant genotypes to eliminate classical scrapie. Transmission of classical scrapie in sheep occurs during the prenatal and periparturient periods when lambs are highly susceptible. Initially, the scrapie agent is disseminated throughout the lymphoid system and into the CNS. Shedding of the scrapie agent occurs before the onset of clinical signs. In contrast to classical scrapie, atypical scrapie is believed to be a spontaneous disease that occurs in isolated instances in older animals within a flock. The agent that causes atypical scrapie is not considered to be naturally transmissible. Transmission of the scrapie agent to species other than sheep, including deer, has been experimentally demonstrated as has the transmission of nonscrapie prion agents to sheep. The purpose of this review is to outline the current methods for diagnosing scrapie in sheep and the techniques used for studying the pathogenesis and host range of the scrapie agent. Also discussed is the US scrapie eradication program including recent updates.
Collapse
|
6
|
Teferedegn EY, Yaman Y, Un C. Five novel PRNP gene polymorphisms and their potential effect on Scrapie susceptibility in three native Ethiopian sheep breeds. BMC Vet Res 2020; 16:122. [PMID: 32349749 PMCID: PMC7189463 DOI: 10.1186/s12917-020-02336-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 04/15/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Classical scrapie susceptibility in sheep has been linked to three polymorphisms at codon 136, 154, and 171 in the prion protein gene (PRNP) whereas atypical scrapie susceptibility is related to polymorphisms at codon 141. Many other variants over the length of the PRNP have been reported. Some of the variants may play crucial roles in fighting against the emergence of a new form of scrapie disease. Scrapie surveillance, scrapie associated genotyping and PRNP characterization studies have been conducted across the globe. However, such in-depth studies have never addressed the African continent's sheep breeds. Therefore, genotyping native Ethiopian sheep breed's PRNP gene has socioeconomic and scientific merits. This study aimed to identify PRNP variants in three native Ethiopian sheep breeds and their potential effect on scrapie susceptibility. RESULTS Five novel variants were identified in the PRNP gene of three native Ethiopian sheep breeds. Four non-synonymous heterozygous substitutions i.e. H99Q (CAC-- > CAA), H99L (CAC-- > CTA), A116E (GCA-- > GAA), A116T (GCA-- > ACA), and one synonymous N103 N (AAC-- > AAT) were detected. In addition to the novel variants, polymorphisms at codon 126,127,138,142,146,231, and 237 were also identified. The haplotype ARR was observed in Menz and Afar breeds at frequencies of 0.02 and 0.05 respectively. Neither ARR/ARR nor VRQ/VRQ genotypes were identified in the population under study. CONCLUSION Two of the novel variants at codon 99 and 103 that are placed closer to the proteinase K cleavage site and the variant at codon 116 in the palindrome region along with variants at codon 127 in glycine repeat domain may influence the conformational flexibility of prion protein. The rarity of ARR haplotype and the abundance of 141 L variant demonstrated that the present study population was less resistant to classical scrapie and less predisposed to genotype associated atypical scrapie. This study provides a valuable dataset that can be potentially integrated into selective breeding strategies during interbreeding, crossbreeding and help to take precautionary measures against scrapie.
Collapse
Affiliation(s)
| | - Yalcin Yaman
- Department of Biometry and Genetics, Bandirma Sheep Research Institute, Bandirma, Balikesir, Turkey
| | - Cemal Un
- Ege University, Department of Biology, Molecular Biology Division, Izmir, Turkey
| |
Collapse
|
7
|
Abstract
Scrapie is a naturally occurring transmissible spongiform encephalopathy (TSE) or prion disease of sheep and goats. Scrapie is a protein misfolding disease where the normal prion protein (PrPC) misfolds into a pathogenic form (PrPSc) that is highly resistant to enzymatic breakdown within the cell and accumulates, eventually leading to neurodegeneration. The amino acid sequence of the prion protein and tissue distribution of PrPSc within affected hosts have a major role in determining susceptibility to and potential environmental contamination with the scrapie agent. Many countries have genotype-based eradication programs that emphasize using rams that express arginine at codon 171 in the prion protein, which is associated with resistance to the classical scrapie agent. In classical scrapie, accumulation of PrPSc within lymphoid and other tissues facilitates environmental contamination and spread of the disease within flocks. A major distinction can be made between classical scrapie strains that are readily spread within populations of susceptible sheep and goats and atypical (Nor-98) scrapie that has unique molecular and phenotype characteristics and is thought to occur spontaneously in older sheep or goats. This review provides an overview of classical and atypical scrapie with consideration of potential transmission of classical scrapie to other mammalian hosts.
Collapse
Affiliation(s)
- Justin J Greenlee
- 1 Virus and Prion Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA, USA
| |
Collapse
|
8
|
Abstract
Scrapie was the first prion disease to be recognised and the study of this disease in sheep and goats has provided a wealth of information not only for scrapie but also for the other prion diseases. All prion diseases are under strong genetic control of the prion gene PRNP, independent of whether they are typical or atypical scrapie and which of the different prion strains is causing infection. Decades of studies using experimental disease challenges and field surveys have established disease association models, in which species-specific amino acid variations in the prion or PrP protein, encoded by the PRNP gene, can predict disease susceptibility or resistance. PRNP genetics represents an important and successful basis for implementing scrapie eradication strategies in sheep and goats. In general terms these studies have revealed that there appear to be many more amino acid changes in PrP leading to increased resistance than to higher susceptibility. Most changes are in the globular part of PrP protein and three regions appear to have major influence. This knowledge can be transferred into prion diseases of other species to facilitate genetic control strategies. However, an obstacle remains with the lack of fully understanding the underlying molecular mechanism, impeding our ability to deal with the difference in the genetic control between typical and atypical forms of scrapie or to predict association in newly infected species. This chapter will discuss the advances in both typical and atypical scrapie from a genetic perspective.
Collapse
Affiliation(s)
- Wilfred Goldmann
- Neurobiology Division, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, United Kingdom.
| |
Collapse
|
9
|
Zabavnik J, Cotman M, Juntes P, Ambrozic I. A decade of using small-to-medium throughput allele discrimination assay to determine prion protein gene ( Prnp) genotypes in sheep in Slovenia. J Vet Diagn Invest 2018; 30:144-149. [PMID: 28906181 PMCID: PMC6504162 DOI: 10.1177/1040638717723946] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Sheep with valine (V) at codon 136 and glutamine (Q) at codon 171 of the prion protein gene ( Prnp) are highly susceptible to classical scrapie, whereas phenylalanine (F) at codon 141 and histidine (H) at codon 154 play a major role in the susceptibility to atypical scrapie. A TaqMan real-time PCR assay was developed to determine Prnp alleles at codons 136, 141, 154, and 171 and used in classical scrapie eradication and breeding programs adopted in Slovenia. The frequency of the most resistant genotypes ARR/ARR and ARR/ARQ increased significantly in tested animals ( n = 35,138) from 6.7 and 27.1% of the tested sheep in 2006 to 12.1 and 32.4%, respectively, in 2015. Frequencies of more susceptible genotypes ARQ/ARQ and ARQ/VRQ decreased significantly from 36.4 and 3.5% in 2006 to 31.1 and 1.8%, respectively, in 2015. The most susceptible genotype VRQ/VRQ was detected in <0.5% of tested sheep. Frequencies of alleles AFRQ and AHQ affecting the susceptibility to atypical scrapie did not change significantly. The developed assay was suitable for genotyping on a small-to-medium throughput scale and was successfully used in classical scrapie eradication, as well as for the selection of classical scrapie-resistant sheep within breeding programs in Slovenia.
Collapse
Affiliation(s)
- Jelka Zabavnik
- Jelka Zabavnik, Institute of
Preclinical Sciences/National Veterinary Institute, Veterinary Faculty,
University of Ljubljana, Gerbiceva 60, 1000 Ljubljana, Slovenia.
| | | | | | | |
Collapse
|
10
|
Pei F, DiSalvo S, Sindi SS, Serio TR. A dominant-negative mutant inhibits multiple prion variants through a common mechanism. PLoS Genet 2017; 13:e1007085. [PMID: 29084237 PMCID: PMC5679637 DOI: 10.1371/journal.pgen.1007085] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 11/09/2017] [Accepted: 10/20/2017] [Indexed: 11/18/2022] Open
Abstract
Prions adopt alternative, self-replicating protein conformations and thereby determine novel phenotypes that are often irreversible. Nevertheless, dominant-negative prion mutants can revert phenotypes associated with some conformations. These observations suggest that, while intervention is possible, distinct inhibitors must be developed to overcome the conformational plasticity of prions. To understand the basis of this specificity, we determined the impact of the G58D mutant of the Sup35 prion on three of its conformational variants, which form amyloids in S. cerevisiae. G58D had been previously proposed to have unique effects on these variants, but our studies suggest a common mechanism. All variants, including those reported to be resistant, are inhibited by G58D but at distinct doses. G58D lowers the kinetic stability of the associated amyloid, enhancing its fragmentation by molecular chaperones, promoting Sup35 resolubilization, and leading to amyloid clearance particularly in daughter cells. Reducing the availability or activity of the chaperone Hsp104, even transiently, reverses curing. Thus, the specificity of inhibition is determined by the sensitivity of variants to the mutant dosage rather than mode of action, challenging the view that a unique inhibitor must be developed to combat each variant.
Collapse
Affiliation(s)
- Fen Pei
- The University of Arizona, Department of Molecular and Cellular Biology, Tucson, Arizona, United States of America
| | - Susanne DiSalvo
- Brown University, Department of Molecular and Cell Biology, Providence, Rhode Island, United States of America
| | - Suzanne S. Sindi
- University of California, Merced, Applied Mathematics, School of Natural Sciences, Merced, California, United States of America
- * E-mail: (SS); (TRS)
| | - Tricia R. Serio
- The University of Arizona, Department of Molecular and Cellular Biology, Tucson, Arizona, United States of America
- * E-mail: (SS); (TRS)
| |
Collapse
|
11
|
Mazza M, Guglielmetti C, Ingravalle F, Brusadore S, Langeveld JPM, Ekateriniadou LV, Andréoletti O, Casalone C, Acutis PL. Low fraction of the 222K PrP variant in the protease-resistant moiety of PrPres in heterozygous scrapie positive goats. J Gen Virol 2017; 98:1963-1967. [PMID: 28691895 PMCID: PMC5656779 DOI: 10.1099/jgv.0.000843] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The presence of lysine (K) at codon 222 has been associated with resistance to classical scrapie in goats, but few scrapie cases have been identified in 222Q/K animals. To investigate the contribution of the 222K variant to PrPres formation in natural and experimental Q/K scrapie cases, we applied an immunoblotting method based on the use of two different monoclonal antibodies, F99/97.6.1 and SAF84, chosen for their different affinities to 222K and 222Q PrP variants. Our finding that PrPres seems to be formed nearly totally by the 222Q variant provides evidence that the 222K PrP variant confers resistance to conversion to PrPres formation and reinforces the view that this mutation has a protective role against classical scrapie in goats.
Collapse
Affiliation(s)
- Maria Mazza
- Italian Reference Centre for TSEs, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Chiara Guglielmetti
- Italian Reference Centre for TSEs, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Francesco Ingravalle
- Biostatistic, Epidemiology and Risk Analysis Unit, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Sonia Brusadore
- Italian Reference Centre for TSEs, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | | | - Loukia V Ekateriniadou
- National Agricultural Research Foundation, Veterinary Research Institute, Thessaloniki, Greece
| | - Olivier Andréoletti
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Cristina Casalone
- Italian Reference Centre for TSEs, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Pier Luigi Acutis
- Italian Reference Centre for TSEs, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| |
Collapse
|
12
|
Silva CJ, Erickson-Beltran ML, Hui C, Badiola JJ, Nicholson EM, Requena JR, Bolea R. Quantitating PrP Polymorphisms Present in Prions from Heterozygous Scrapie-Infected Sheep. Anal Chem 2016; 89:854-861. [PMID: 27936597 DOI: 10.1021/acs.analchem.6b03822] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Scrapie is a prion (PrPSc) disease of sheep. The incubation period of sheep scrapie is strongly influenced by polymorphisms at positions 136, 154, and 171 of a sheep's normal cellular prion protein (PrPC). Chymotrypsin was used to digest sheep recombinant PrP to identify a set of characteristic peptides [M132LGSXMSRPL141 (X = A or V), Y153XENMY158 (X,= H or R), and Y166RPVDXY172 (X = H, K, Q, or R)] that could be used to detect and quantitate polymorphisms at positions 136, 154, and 171 of sheep PrPC or PrPSc. These peptides were used to develop a multiple reaction monitoring method (MRM) to detect the amounts of a particular polymorphism in a sample of PrPSc isolated from sheep heterozygous for their PrPC proteins. The limit of detection for these peptides was less than 50 attomole. Spinal cord tissue from heterozygous (ARQ/VRQ or ARH/ARQ) scrapie-infected Rasa Aragonesa sheep was analyzed using this MRM method. Both sets of heterozygotes show the presence of both polymorphisms in PrPSc. This was true for samples containing both proteinase K (PK)-sensitive and PK-resistant PrPSc and samples containing only the PK-resistant PrPSc. These results show that heterozygous animals contain PrPSc that is composed of significant amounts of both PrP polymorphisms.
Collapse
Affiliation(s)
- Christopher J Silva
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service , Albany, California 94710, United States
| | - Melissa L Erickson-Beltran
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service , Albany, California 94710, United States
| | - Colleen Hui
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service , Albany, California 94710, United States
| | - Juan José Badiola
- Veterinary Faculty, Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes (CIEETE), Universidad de Zaragoza , 50013, Zaragoza Spain
| | - Eric M Nicholson
- Virus and Prion Research Unit, National Animal Disease Center, United States Department of Agriculture, Agricultural Research Service , Ames, Iowa 50010, United States
| | - Jesús R Requena
- CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS , Santiago de Compostela, 15782 Spain
| | - Rosa Bolea
- Veterinary Faculty, Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes (CIEETE), Universidad de Zaragoza , 50013, Zaragoza Spain
| |
Collapse
|
13
|
Prion Type-Dependent Deposition of PRNP Allelic Products in Heterozygous Sheep. J Virol 2015; 90:805-12. [PMID: 26512080 PMCID: PMC4702698 DOI: 10.1128/jvi.02316-15] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Accepted: 10/08/2015] [Indexed: 01/09/2023] Open
Abstract
UNLABELLED Susceptibility or resistance to prion infection in humans and animals depends on single prion protein (PrP) amino acid substitutions in the host, but the agent's modulating role has not been well investigated. Compared to disease incubation times in wild-type homozygous ARQ/ARQ (where each triplet represents the amino acids at codons 136, 154, and 171, respectively) sheep, scrapie susceptibility is reduced to near resistance in ARR/ARR animals while it is strongly enhanced in VRQ/VRQ carriers. Heterozygous ARR/VRQ animals exhibit delayed incubation periods. In bovine spongiform encephalopathy (BSE) infection, the polymorphism effect is quite different although the ARR allotype remains the least susceptible. In this study, PrP allotype composition in protease-resistant prion protein (PrP(res)) from brain of heterozygous ARR/VRQ scrapie-infected sheep was compared with that of BSE-infected sheep with a similar genotype. A triplex Western blotting technique was used to estimate the two allotype PrP fractions in PrP(res) material from BSE-infected ARR/VRQ sheep. PrP(res) in BSE contained equimolar amounts of VRQ- and ARR-PrP, which contrasts with the excess (>95%) VRQ-PrP fraction found in PrP in scrapie. This is evidence that transmissible spongiform encephalopathy (TSE) agent properties alone, perhaps structural aspects of prions (such as PrP amino acid sequence variants and PrP conformational state), determine the polymorphic dependence of the PrP(res) accumulation process in prion formation as well as the disease-associated phenotypic expressions in the host. IMPORTANCE Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative and transmissible diseases caused by prions. Amino acid sequence variants of the prion protein (PrP) determine transmissibility in the hosts, as has been shown for classical scrapie in sheep. Each individual produces a separate PrP molecule from its two PrP gene copies. Heterozygous scrapie-infected sheep that produce two PrP variants associated with opposite scrapie susceptibilities (136V-PrP variant, high; 171R-PrP variant, very low) contain in their prion material over 95% of the 136V PrP variant. However, when these sheep are infected with prions from cattle (bovine spongiform encephalopathy [BSE]), both PrP variants occur in equal ratios. This shows that the infecting prion type determines the accumulating PrP variant ratio in the heterozygous host. While the host's PrP is considered a determining factor, these results emphasize that prion structure plays a role during host infection and that PrP variant involvement in prions of heterozygous carriers is a critical field for understanding prion formation.
Collapse
|
14
|
Comparative Susceptibility of Sheep of Different Origins, Breeds and PRNP Genotypes to Challenge with Bovine Spongiform Encephalopathy and Scrapie. PLoS One 2015; 10:e0143251. [PMID: 26587837 PMCID: PMC4654545 DOI: 10.1371/journal.pone.0143251] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 11/02/2015] [Indexed: 01/09/2023] Open
Abstract
Sheep are natural hosts of the prion disease, scrapie. They are also susceptible to experimental challenge with various scrapie strains and with bovine spongiform encephalopathy (BSE), which affects cattle and has been accidentally transmitted to a range of other species, including man. Incidence and incubation period of clinical disease in sheep following inoculation is controlled by the PRNP gene, which has different alleles defined on the basis of polymorphisms, particularly at codons 136, 154 and 171, although other codons are associated with survival time, and the exact responses of the sheep may be influenced by other breed-related differences. Here we report the results of a long term single study of experimental scrapie and BSE susceptibility of sheep of Cheviot, Poll Dorset and Suffolk breeds, originating from New Zealand and of a wide range of susceptible and resistant PRNP genotypes. Responses were compared with those of sheep from a closed Cheviot flock of UK origin (Roslin Cheviot flock). The unusually long observation period (6-8 years for most, but up to 12 years for others) allows us to draw robust conclusions about rates of survival of animals previously regarded as resistant to infection, particularly PRNP heterozygotes, and is the most comprehensive such study reported to date. BSE inoculation by an intracerebral route produced disease in all genotype groups with differing incubation periods, although M112T and L141F polymorphisms seemed to give some protection. Scrapie isolate SSBP/1, which has the shortest incubation period in sheep with at least one VRQ PRNP allele, also produced disease following sub-cutaneous inoculation in ARQ/ARQ animals of New Zealand origin, but ARQ/ARQ sheep from the Roslin flock survived the challenge. Our results demonstrate that the links between PRNP genotype and clinical prion disease in sheep are much less secure than previously thought, and may break down when, for example, a different breed of sheep is moved into a new flock.
Collapse
|
15
|
Jeffrey M, Martin S, Chianini F, Eaton S, Dagleish MP, González L. Incidence of infection in Prnp ARR/ARR sheep following experimental inoculation with or natural exposure to classical scrapie. PLoS One 2014; 9:e91026. [PMID: 24614120 PMCID: PMC3948952 DOI: 10.1371/journal.pone.0091026] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 02/06/2014] [Indexed: 12/02/2022] Open
Abstract
The prion protein gene (Prnp) is highly influential in determining risk and susceptibility of sheep exposed to classical scrapie. Sheep homozygous for alanine at codon 136 and arginine at codons 154 and 171 (ARR/ARR) of the Prnp gene are historically considered to be highly resistant to classical scrapie, although they form a significant fraction of cases of atypical scrapie. To date, experimental transmission of prions to ARR/ARR sheep has only been achieved with the BSE agent and mostly by the intracerebral route. We summarise here the results of six separate studies, in which 95 sheep of the ARR/ARR genotype were naturally exposed to (n = 18) or experimentally challenged with (n = 77) natural or experimental sources of classical scrapie by the oral, intra-intestinal, subcutaneous or intracerebral routes and allowed to survive for periods of up to 94 months post-infection. Only the intracerebral route resulted in disease and/or amplification of disease associated PrP (PrPd), and only in two of 19 sheep that survived for longer than 36 months. Discriminatory immunohistochemistry and Western blot confirmed the scrapie, non-BSE signature of PrPd in those two sheep. However, the neuropathological phenotype was different from any other scrapie (classical or atypical) or BSE source previously reported in sheep of any Prnp genotype. These studies confirm the widely held view that ARR/ARR sheep are highly resistant to classical scrapie infection, at least within their commercial lifespan. Moreover, within the constraints of the present studies (only two infected sheep), these results do not support the suggestion that atypical scrapie or BSE are generated by adaptation or mutation of classical scrapie in sheep of resistant ARR/ARR genotype.
Collapse
Affiliation(s)
- Martin Jeffrey
- Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade), Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, United Kingdom
- * E-mail:
| | - Stuart Martin
- Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade), Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, United Kingdom
| | - Francesca Chianini
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, United Kingdom
| | - Samantha Eaton
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, United Kingdom
| | - Mark P. Dagleish
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, United Kingdom
| | - Lorenzo González
- Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade), Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, United Kingdom
| |
Collapse
|
16
|
Expanding possibilities for intervention against small ruminant lentiviruses through genetic marker-assisted selective breeding. Viruses 2013; 5:1466-99. [PMID: 23771240 PMCID: PMC3717717 DOI: 10.3390/v5061466] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 06/01/2013] [Accepted: 06/07/2013] [Indexed: 12/25/2022] Open
Abstract
Small ruminant lentiviruses include members that infect sheep (ovine lentivirus [OvLV]; also known as ovine progressive pneumonia virus/maedi-visna virus) and goats (caprine arthritis encephalitis virus [CAEV]). Breed differences in seroprevalence and proviral concentration of OvLV had suggested a strong genetic component in susceptibility to infection by OvLV in sheep. A genetic marker test for susceptibility to OvLV has been developed recently based on the TMEM154 gene with validation data from over 2,800 sheep representing nine cohorts. While no single genotype has been shown to have complete resistance to OvLV, consistent association in thousands of sheep from multiple breeds and management conditions highlight a new strategy for intervention by selective breeding. This genetic marker-assisted selection (MAS) has the potential to be a useful addition to existing viral control measures. Further, the discovery of multiple additional genomic regions associated with susceptibility to or control of OvLV suggests that additional genetic marker tests may be developed to extend the reach of MAS in the future. This review will cover the strengths and limitations of existing data from host genetics as an intervention and outline additional questions for future genetic research in sheep, goats, small ruminant lentiviruses, and their host-pathogen interactions.
Collapse
|
17
|
Chianini F, Sisó S, Ricci E, Eaton SL, Finlayson J, Pang Y, Hamilton S, Steele P, Reid HW, Cantile C, Sales J, Jeffrey M, Dagleish MP, González L. Pathogenesis of scrapie in ARQ/ARQ sheep after subcutaneous infection: effect of lymphadenectomy and immune cell subset changes in relation to prion protein accumulation. Vet Immunol Immunopathol 2013; 152:348-58. [PMID: 23398720 DOI: 10.1016/j.vetimm.2013.01.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 01/07/2013] [Accepted: 01/10/2013] [Indexed: 12/19/2022]
Abstract
It is well established that the infectious agent of scrapie can replicate in the lymphoreticular system (LRS). However, the effects of removal of LRS target tissues on the pathogenesis of the infection and the accumulation of disease-associated prion protein (PrP(d)) in LRS tissues on specific immune cell subsets are poorly understood aspects. To address these questions 16 ARQ/ARQ sheep were subcutaneously inoculated in the drainage area of the prefemoral lymph node with brain homogenate derived from Suffolk sheep naturally infected with scrapie. Fourteen sheep were then subjected to either early (14-17 days post-inoculation [dpi]) or late (175-201 dpi) lymphadenectomy and culled at preclinical or clinical stages of infection. Neither late nor even early lymphadenectomy prevented infection or had any effect on the accumulation of PrP(d) in the LRS or CNS suggesting a rapid organic dissemination of the infectious agent after inoculation. Lymph nodes from eight scrapie inoculated sheep selected on the basis of the amount of PrP(d) in their LRS tissues (negative, low or high) were examined for six different immune cell markers. The PrP(d) negative lymph nodes from two sheep with no evidence of scrapie infection showed lower numbers of cluster of determination (CD) 21 positive cells than PrP(d) positive nodes, irrespective of their location (hind leg or head). However, quantitative differences in the expression of this marker were not detected when comparing lymph nodes with low and high levels of PrP(d) accumulation, suggesting that proliferation of CD21 positive cells is related to scrapie infection, but not directly linked to the magnitude of PrP(d) accumulation. An additional observation of the study was that sheep that were methionin-threonine at codon 112 of the prion protein gene showed lower attack rates than methionine homozygotes (67% and 100%, respectively) and also generally lower levels of PrP(d) accumulation in the LRS and brain and increased survival times, suggesting an influence of such polymorphism in the susceptibility to scrapie.
Collapse
Affiliation(s)
- F Chianini
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland, UK.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Hautaniemi M, Tapiovaara H, Korpenfelt SL, Sihvonen L. Genotyping and surveillance for scrapie in Finnish sheep. BMC Vet Res 2012; 8:122. [PMID: 22831168 PMCID: PMC3414783 DOI: 10.1186/1746-6148-8-122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 07/25/2012] [Indexed: 11/12/2022] Open
Abstract
Background The progression of scrapie is known to be influenced by the amino acid polymorphisms of the host prion protein (PrP) gene. There is no breeding programme for TSE resistance in sheep in Finland, but a scrapie control programme has been in place since 1995. In this study we have analysed PrP genotypes of total of 928 purebred and crossbred sheep together with the data of scrapie survey carried out in Finland during 2002–2008 in order to gain knowledge of the genotype distribution and scrapie prevalence in Finnish sheep. Results The ARQ/ARQ genotype was the most common genotype in all breeds studied. ARR allele frequency was less than 12% in purebred Finnish sheep and in most genotypes heterozygous for ARR, the second allele was ARQ. The VRQ allele was not detected in the Grey race sheep of Kainuu or in the Aland sheep, and it was present in less than 6% of the Finnish Landrace sheep. Leucine was the most prominent amino acid found in codon 141. In addition, one novel prion dimorphisms of Q220L was detected. During the scrapie survey of over 15 000 sheep in 2002–2008, no classical scrapie cases and only five atypical scrapie cases were detected. Conclusions The results indicate that the Finnish sheep populations have genetically little resistance to classical scrapie, but no classical scrapie was detected during an extensive survey in 2002–2008. However, five atypical scrapie cases emerged; thus, the disease is present in the Finnish sheep population at a low level.
Collapse
Affiliation(s)
- Maria Hautaniemi
- Research Department/Veterinary Virology, Finnish Food Safety Authority Evira, Mustialankatu 3, FI-00790, Helsinki, Finland.
| | | | | | | |
Collapse
|
19
|
González L, Jeffrey M, Dagleish MP, Goldmann W, Sisó S, Eaton SL, Martin S, Finlayson J, Stewart P, Steele P, Pang Y, Hamilton S, Reid HW, Chianini F. Susceptibility to scrapie and disease phenotype in sheep: cross-PRNP genotype experimental transmissions with natural sources. Vet Res 2012; 43:55. [PMID: 22748008 PMCID: PMC3460791 DOI: 10.1186/1297-9716-43-55] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 06/14/2012] [Indexed: 11/10/2022] Open
Abstract
It has long been established that the sheep Prnp genotype influences the susceptibility to scrapie, and some studies suggest that it can also determine several aspects of the disease phenotype. Other studies, however, indicate that the source of infection may also play a role in such phenotype. To address this question an experiment was set up in which either of two different natural scrapie sources, AAS from AA136 Suffolk and VVC from VV136 Cheviot sheep, were inoculated into AA136, VA136 and VV136 sheep recipients (n = 52). The immunohistochemical (IHC) profile of disease-associated PrP (PrPd) accumulation in the brain of recipient sheep was highly consistent upon codon 136 homologous and semi-homologous transmission, but could be either similar to or different from those of the inoculum donors. In contrast, the IHC profiles were highly variable upon heterologous transmission (VVC to AA136 and AAS to VV136). Furthermore, sheep of the same Prnp genotype could exhibit different survival times and PrPd profiles depending on the source of infection, and a correlation was observed between IHC and Western blot profiles. It was found that additional polymorphisms at codons 112 or 141 of AA136 recipients resulted in a delayed appearance of clinical disease or even in protection from infection. The results of this study strongly suggest that the scrapie phenotype in sheep results from a complex interaction between source, donor and recipient factors, and that the Prnp genotype of the recipient sheep does not explain the variability observed upon codon 136 heterologous transmissions, arguing for other genetic factors to be involved.
Collapse
Affiliation(s)
- Lorenzo González
- Animal Health and Veterinary Laboratories Agency, Pentlands Science Park, Bush Loan, Midlothian, EH26 0PZ, United Kingdom.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Sisó S, Chianini F, Eaton SL, Witz J, Hamilton S, Martin S, Finlayson J, Pang Y, Stewart P, Steele P, Dagleish MP, Goldmann W, Reid HW, Jeffrey M, Gonzalez L. Disease phenotype in sheep after infection with cloned murine scrapie strains. Prion 2012; 6:174-83. [PMID: 22421207 PMCID: PMC7082089 DOI: 10.4161/pri.18990] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Prion diseases exhibit different disease phenotypes in their natural hosts and when transmitted to rodents, and this variability is regarded as indicative of prion strain diversity. Phenotypic characterization of scrapie strains in sheep can be attempted by histological, immunohistochemical and biochemical approaches, but it is widely considered that strain confirmation and characterization requires rodent bioassay. Examples of scrapie strains obtained from original sheep isolates by serial passage in mice include ME7, 79A, 22A and 87V. In order to address aspects of prion strain stability across the species barrier, we transmitted the above murine strains to sheep of different breeds and susceptible Prnp genotypes. The experiment included 40 sheep dosed by the oral route alone and 36 sheep challenged by combined subcutaneous and intracerebral routes. Overall, the combined route produced higher attack rates (~100%) than the oral route (~50%) and 2-4 times shorter incubation periods. Uniquely, 87V given orally was unable to infect any sheep. Overall, scrapie strains adapted and cloned in mice produce distinct but variable disease phenotypes in sheep depending on breed or Prnp genotype. Further re-isolation experiments in mice are in progress in order to determine whether the original cloned murine disease phenotype will reemerge.
Collapse
Affiliation(s)
- Silvia Sisó
- Department of Pathology; Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade); Pentlands Science Park; Midlothian, UK,Current affiliation: Deptartments of Pathology, Microbiology and Immunology; University of California Davis; Davis, CA USA,Correspondence to: Silvia Sisó,
| | | | | | - Janey Witz
- Department of Pathology; Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade); Pentlands Science Park; Midlothian, UK
| | - Scott Hamilton
- Moredun Research Institute; Pentlands Science Park; Midlothian, UK
| | - Stuart Martin
- Department of Pathology; Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade); Pentlands Science Park; Midlothian, UK
| | - Jeanie Finlayson
- Moredun Research Institute; Pentlands Science Park; Midlothian, UK
| | - Yvonne Pang
- Moredun Research Institute; Pentlands Science Park; Midlothian, UK
| | | | - Philip Steele
- Moredun Research Institute; Pentlands Science Park; Midlothian, UK
| | - Mark P. Dagleish
- Moredun Research Institute; Pentlands Science Park; Midlothian, UK
| | | | - Hugh W. Reid
- Moredun Research Institute; Pentlands Science Park; Midlothian, UK
| | - Martin Jeffrey
- Department of Pathology; Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade); Pentlands Science Park; Midlothian, UK
| | - Lorenzo Gonzalez
- Department of Pathology; Animal Health and Veterinary Laboratories Agency (AHVLA-Lasswade); Pentlands Science Park; Midlothian, UK
| |
Collapse
|
21
|
Hedlin P, Taschuk R, Potter A, Griebel P, Napper S. Detection and control of prion diseases in food animals. ISRN VETERINARY SCIENCE 2012; 2012:254739. [PMID: 23738120 PMCID: PMC3658581 DOI: 10.5402/2012/254739] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 12/22/2011] [Indexed: 12/14/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs), or prion diseases, represent a unique form of infectious disease based on misfolding of a self-protein (PrPC) into a pathological, infectious conformation (PrPSc). Prion diseases of food animals gained notoriety during the bovine spongiform encephalopathy (BSE) outbreak of the 1980s. In particular, disease transmission to humans, to the generation of a fatal, untreatable disease, elevated the perspective on livestock prion diseases from food production to food safety. While the immediate threat posed by BSE has been successfully addressed through surveillance and improved management practices, another prion disease is rapidly spreading. Chronic wasting disease (CWD), a prion disease of cervids, has been confirmed in wild and captive populations with devastating impact on the farmed cervid industries. Furthermore, the unabated spread of this disease through wild populations threatens a natural resource that is a source of considerable economic benefit and national pride. In a worst-case scenario, CWD may represent a zoonotic threat either through direct transmission via consumption of infected cervids or through a secondary food animal, such as cattle. This has energized efforts to understand prion diseases as well as to develop tools for disease detection, prevention, and management. Progress in each of these areas is discussed.
Collapse
Affiliation(s)
- Peter Hedlin
- Department of Biochemistry, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3 ; Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3
| | | | | | | | | |
Collapse
|
22
|
Rubenstein R, Bulgin MS, Chang B, Sorensen-Melson S, Petersen RB, LaFauci G. PrP(Sc) detection and infectivity in semen from scrapie-infected sheep. J Gen Virol 2012; 93:1375-1383. [PMID: 22323531 DOI: 10.1099/vir.0.038802-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A scrapie-positive ewe was found in a flock that had been scrapie-free for 13 years, but housed adjacent to scrapie-positive animals, separated by a wire fence. Live animal testing of the entire flock of 24 animals revealed seven more subclinical scrapie-positive ewes. We hypothesized that they may have contracted the disease from scrapie-positive rams used for breeding 4 months prior, possibly through the semen. The genotypes of the ewe flock were highly scrapie-susceptible and the rams were infected with the 'Caine' scrapie strain having a short incubation time of 4.3-14.6 months in sheep with 136/171 VQ/VQ and AQ/VQ genotypes. PrP(Sc) accumulates in a variety of tissues in addition to the central nervous system. Although transmission of prion diseases, or transmissible spongiform encephalopathies, has been achieved via peripheral organ or tissue homogenates as well as by blood transfusion, neither infectivity nor PrP(Sc) have been found in semen from scrapie-infected animals. Using serial protein misfolding cyclic amplification followed by a surround optical fibre immunoassay, we demonstrate that semen from rams infected with a short-incubation-time scrapie strain contains prion disease-associated-seeding activity that generated PrP(Sc) in sPMCA (serial protein misfolding cyclic amplification). Injection of the ovinized transgenic mouse line TgSShpPrP with semen from scrapie-infected sheep resulted in PrP(Sc)-seeding activity in clinical and, probably as a result of the low titre, non-clinical mouse brain. These results suggest that the transmissible agent, or at least the seeding activity, for sheep scrapie is present in semen. This may be a strain-specific phenomenon.
Collapse
Affiliation(s)
- Richard Rubenstein
- Departments of Neurology and Physiology/Pharmacology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
| | - Marie S Bulgin
- University of Idaho, Caine Veterinary Teaching and Research Center, 1020 E. Homedale Road, Caldwell, ID 83607, USA
| | - Binggong Chang
- Departments of Neurology and Physiology/Pharmacology, SUNY Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
| | - Sharon Sorensen-Melson
- University of Idaho, Caine Veterinary Teaching and Research Center, 1020 E. Homedale Road, Caldwell, ID 83607, USA
| | - Robert B Petersen
- Departments of Pathology Neuroscience, and Neurology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44120, USA
| | - Giuseppe LaFauci
- New York State Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA
| |
Collapse
|
23
|
Frootan F, Nikbakht G, Özgentürk NÖ, Ün C. Prion Protein Coding Gene (PRNP) Variability in Sheep from Turkey and Iran. Biochem Genet 2011; 50:277-84. [DOI: 10.1007/s10528-011-9470-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Accepted: 08/29/2011] [Indexed: 11/30/2022]
|
24
|
Proteinase K-resistant material in ARR/VRQ sheep brain affected with classical scrapie is composed mainly of VRQ prion protein. J Virol 2011; 85:12537-46. [PMID: 21917981 DOI: 10.1128/jvi.00448-11] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Classical scrapie is a prion disease in sheep and goats. In sheep, susceptibility to disease is genetically influenced by single amino acid substitutions. Genetic breeding programs aimed at enrichment of arginine-171 (171R) prion protein (PrP), the so-called ARR allele, in the sheep population have been demonstrated to be effective in reducing the occurrence of classical scrapie in the field. Understanding the molecular basis for this reduced prevalence would serve the assessment of ARR adaptation. The prion formation mechanism and conversion of PrP from the normal form (PrP(C)) to the scrapie-associated form (PrP(Sc)) could play a key role in this process. Therefore, we investigated whether the ARR allele substantially contributes to scrapie prion formation in naturally infected heterozygous 171Q/R animals. Two methods were applied to brain tissue of 171Q/R heterozygous sheep with natural scrapie to determine the relative amount of the 171R PrP fraction in PrP(res), the proteinase K-resistant PrP(Sc) core. An antibody test differentiating between 171Q and 171R PrP fragments showed that PrP(res) was mostly composed of the 171Q allelotype. Furthermore, using a novel tool for prion research, endoproteinase Lys-C-digested PrP(res) yielded substantial amounts of a nonglycosylated and a monoglycosylated PrP fragment comprising codons 114 to 188. Following two-dimensional gel electrophoresis, only marginal amounts (<9%) of 171R PrP(res) were detected. Enhanced 171R(res) proteolytic susceptibility could be excluded. Thus, these data support a nearly zero contribution of 171R PrP in PrP(res) of 171R/Q field scrapie-infected animals. This is suggestive of a poor adaptation of classical scrapie to this resistance allele under these natural conditions.
Collapse
|
25
|
González L, Dagleish MP, Martin S, Finlayson J, Sisó S, Eaton SL, Goldmann W, Witz J, Hamilton S, Stewart P, Pang Y, Steele P, Reid HW, Chianini F, Jeffrey M. Factors influencing temporal variation of scrapie incidence within a closed Suffolk sheep flock. J Gen Virol 2011; 93:203-211. [PMID: 21918004 DOI: 10.1099/vir.0.034652-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Several studies have shown that transmission of natural scrapie can occur vertically and horizontally, and that variations in scrapie incidence between and within infected flocks are mostly due to differences in the proportion of sheep with susceptible and resistant PRNP genotypes. This report presents the results of a 12-year period of scrapie monitoring in a closed flock of Suffolk sheep, in which only animals of the ARQ/ARQ genotype developed disease. Among a total of 120 of these, scrapie attack rates varied between birth cohorts from 62.5 % (5/8) to 100 % (9/9), and the incidence of clinical disease among infected sheep from 88.9 % (8/9) to 100 % (in five birth cohorts). Susceptible sheep born to scrapie-infected ewes showed a slightly higher risk of becoming infected (97.2 %), produced earlier biopsy-positive results (mean 354 days) and developed disease at a younger age (median 736 days) than those born to non-infected dams (80.3 %, 451 and 782 days, respectively). Taken together, this was interpreted as evidence of maternal transmission. However, it was also observed that, for the birth cohorts with the highest incidence of scrapie (90-100 %), sheep born to infected and non-infected dams had a similar risk of developing scrapie (97.1 and 95.3 %, respectively). Compared with moderate-attack-rate cohorts (62.5-66.7 %), high-incidence cohorts had greater numbers of susceptible lambs born to infected ewes, suggesting that increased rates of horizontal transmission in these cohorts could have been due to high levels of environmental contamination caused by infected placentas.
Collapse
Affiliation(s)
- Lorenzo González
- Animal Health and Veterinary Laboratories Agency (AHVLA), Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Mark P Dagleish
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Stuart Martin
- Animal Health and Veterinary Laboratories Agency (AHVLA), Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Jeanie Finlayson
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Sílvia Sisó
- Animal Health and Veterinary Laboratories Agency (AHVLA), Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Samantha L Eaton
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Wilfred Goldmann
- The Roslin Institute and R(D)SVS University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Janey Witz
- Animal Health and Veterinary Laboratories Agency (AHVLA), Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Scott Hamilton
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Paula Stewart
- The Roslin Institute and R(D)SVS University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Yvonne Pang
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Philip Steele
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Hugh W Reid
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Francesca Chianini
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| | - Martin Jeffrey
- Animal Health and Veterinary Laboratories Agency (AHVLA), Pentlands Science Park, Bush Loan, Midlothian EH26 0PZ, UK
| |
Collapse
|
26
|
Assessment of the genetic susceptibility of sheep to scrapie by protein misfolding cyclic amplification and comparison with experimental scrapie transmission studies. J Virol 2011; 85:8386-92. [PMID: 21680531 DOI: 10.1128/jvi.00241-11] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The susceptibility of sheep to scrapie is influenced mainly by the prion protein polymorphisms A136V, R154H, and Q171R/H. Here we analyzed the ability of protein misfolding cyclic amplification (PMCA) to model the genetic susceptibility of sheep to scrapie. For this purpose, we studied the efficiency of brain homogenates from sheep with different PrP genotypes to support PrP(Sc) amplification by PMCA using an ARQ/ARQ scrapie inoculum. The results were then compared with those obtained in vivo using the same sheep breed, genotypes, and scrapie inoculum. Genotypes associated with susceptibility (ARQ/ARQ, ARQ/AHQ, and AHQ/ARH) were able to sustain PrP(Sc) amplification in PMCA reactions, while genotypes associated with resistance to scrapie (ARQ/ARR and ARR/ARR) were unable to support the in vitro conversion. The incubation times of the experimental infection were then compared with the in vitro amplification factors. Linear regression analysis showed that the efficiency of in vitro PrP(Sc) amplification of the different genotypes was indeed inversely proportional to their incubation times. Finally, the rare ARQK₁₇₆/ARQK₁₇₆ genotype, for which no in vivo data are available, was studied by PMCA. No amplification was obtained, suggesting ARQK₁₇₆/ARQK₁₇₆ as an additional genotype associated with resistance, at least to the isolate tested. Our results indicate a direct correlation between the ability of different PrP genotypes to undergo PrP(C)-to-PrP(Sc) conversion by PMCA and their in vivo susceptibility and point to PMCA as an alternative to transmission studies and a potential tool to test the susceptibility of numerous sheep PrP genotypes to a variety of prion sources.
Collapse
|
27
|
Guan F, Pan L, Li J, Tang H, Zhu C, Shi G. Polymorphisms of the prion protein gene and their effects on litter size and risk evaluation for scrapie in Chinese Hu sheep. Virus Genes 2011; 43:147-52. [PMID: 21556743 PMCID: PMC3124648 DOI: 10.1007/s11262-011-0609-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Accepted: 04/04/2011] [Indexed: 11/26/2022]
Abstract
It is well known that scrapie is a fatal, neurodegenerative disease in sheep and goat, which belongs to the group of transmissible spongiform encephalopathies (TSEs) or prion diseases. It has been confirmed that the polymorphisms of prion protein gene (PRNP) at codons 136, 154, and 171 have strong relationship with scrapie in sheep. In the present study, nine polymorphisms of PRNP at codons 136, 154, and 171 and other six loci (at codons 101, 112, 127, 137, 138, and 152) were detected in 180 Chinese Hu sheep. All the alleles at codons 136, 154, and 171 have been identified and resulted in three new genotypes. The frequencies of predominant alleles were 85% (A136), 99.40% (R154), and 37.78% (Q171), respectively. The predominant haplotype ARQ has a relatively high frequency of 57.77%. The frequencies of dominant genotypes of ARR/ARQ and ARQ/ARQ were 30 and 26.67%, respectively. Three new found genotypes named ARQ/TRK, ARQ/TRR, and TRR/TRQ had the same lower frequencies (0.56%). The relationship of PRNP genotype with scrapie risk and litter size showed that the predominant genotypes are corresponded to the risk score of R1 (1.67%), R2 (32.22%), and R3 (42.22%). Just at the first parity, the individuals with ARH/ARH genotype had significantly larger litter size than the mean value and those with ARQ/ARQ and ARR/ARQ genotypes. In short, this study provided preliminary information about alleles and genotypes of PRNP in Chinese Hu sheep. It could be concluded that Hu sheep has a low susceptibility to natural scrapie, and the predominant PRNP genotype at least has no significant effect on litter size.
Collapse
Affiliation(s)
- Feng Guan
- College of Life Sciences, China Jiliang University, Hangzhou, 310018 People’s Republic of China
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, China Jiliang University, Hangzhou, 310018 China
| | - Lei Pan
- College of Life Sciences, China Jiliang University, Hangzhou, 310018 People’s Republic of China
| | - Jie Li
- College of Life Sciences, China Jiliang University, Hangzhou, 310018 People’s Republic of China
| | - Hong Tang
- The Key Sheep Breeding and Reproduction Biotechnology Laboratory of Xinjiang Production and Construction Group, Shihezi, 832000 People’s Republic of China
| | - Cheng Zhu
- College of Life Sciences, China Jiliang University, Hangzhou, 310018 People’s Republic of China
| | - Guoqing Shi
- The Key Sheep Breeding and Reproduction Biotechnology Laboratory of Xinjiang Production and Construction Group, Shihezi, 832000 People’s Republic of China
| |
Collapse
|
28
|
Dominant prion mutants induce curing through pathways that promote chaperone-mediated disaggregation. Nat Struct Mol Biol 2011; 18:486-92. [PMID: 21423195 PMCID: PMC3082495 DOI: 10.1038/nsmb.2031] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Accepted: 12/16/2010] [Indexed: 12/15/2022]
Abstract
Protein misfolding underlies many neurodegenerative diseases, including the transmissible spongiform encephalopathies (prion diseases). Although cells typically recognize and process misfolded proteins, prion proteins evade protective measures by forming stable, self-replicating aggregates. However, coexpression of dominant-negative prion mutants can overcome aggregate accumulation and disease progression through currently unknown pathways. Here we determine the mechanisms by which two mutants of the Saccharomyces cerevisiae Sup35 protein cure the [PSI(+)] prion. We show that both mutants incorporate into wild-type aggregates and alter their physical properties in different ways, diminishing either their assembly rate or their thermodynamic stability. Whereas wild-type aggregates are recalcitrant to cellular intervention, mixed aggregates are disassembled by the molecular chaperone Hsp104. Thus, rather than simply blocking misfolding, dominant-negative prion mutants target multiple events in aggregate biogenesis to enhance their susceptibility to endogenous quality-control pathways.
Collapse
|
29
|
Geoghegan JC, Miller MB, Kwak AH, Harris BT, Supattapone S. Trans-dominant inhibition of prion propagation in vitro is not mediated by an accessory cofactor. PLoS Pathog 2009; 5:e1000535. [PMID: 19649330 PMCID: PMC2713408 DOI: 10.1371/journal.ppat.1000535] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Accepted: 07/08/2009] [Indexed: 11/21/2022] Open
Abstract
Previous studies identified prion protein (PrP) mutants which act as dominant negative inhibitors of prion formation through a mechanism hypothesized to require an unidentified species-specific cofactor termed protein X. To study the mechanism of dominant negative inhibition in vitro, we used recombinant PrPC molecules expressed in Chinese hamster ovary cells as substrates in serial protein misfolding cyclic amplification (sPMCA) reactions. Bioassays confirmed that the products of these reactions are infectious. Using this system, we find that: (1) trans-dominant inhibition can be dissociated from conversion activity, (2) dominant-negative inhibition of prion formation can be reconstituted in vitro using only purified substrates, even when wild type (WT) PrPC is pre-incubated with poly(A) RNA and PrPSc template, and (3) Q172R is the only hamster PrP mutant tested that fails to convert into PrPSc and that can dominantly inhibit conversion of WT PrP at sub-stoichiometric levels. These results refute the hypothesis that protein X is required to mediate dominant inhibition of prion propagation, and suggest that PrP molecules compete for binding to a nascent seeding site on newly formed PrPSc molecules, most likely through an epitope containing residue 172. Over the past two decades, various investigators have observed that heterozygous animals possessing two different forms of the gene encoding the prion protein (PrP) are more difficult to infect with some strains of infectious prions than homozygous animals possessing only the most commonly occurring form of the gene encoding PrP for that species. In 1995, it was hypothesized that the inhibition of prion infection in heterozygous animals might be caused by competition between the two different types of PrP molecules for binding to a common cofactor required for prion propagation, provisionally named “protein X,” through a specific portion of the PrP molecule. Here, we report that mixing different purified PrP molecules together in test tube reactions lacking accessory proteins can also interfere with prion propagation. We also found that some mutations of the putative protein X binding site do not inhibit the formation of hamster prions in chemical reactions. Our work suggests that different PrP molecules most likely compete for binding to newly formed prions rather than an accessory protein cofactor, and argues against the existence of protein X.
Collapse
Affiliation(s)
- James C. Geoghegan
- Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire, United States of America
| | - Michael B. Miller
- Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire, United States of America
| | - Aimee H. Kwak
- Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire, United States of America
| | - Brent T. Harris
- Department of Pathology, Dartmouth Medical School, Hanover, New Hampshire, United States of America
| | - Surachai Supattapone
- Department of Biochemistry, Dartmouth Medical School, Hanover, New Hampshire, United States of America
- Department of Medicine, Dartmouth Medical School, Hanover, New Hampshire, United States of America
- * E-mail:
| |
Collapse
|
30
|
Saunders GC, Lantier I, Cawthraw S, Berthon P, Moore SJ, Arnold ME, Windl O, Simmons MM, Andréoletti O, Bellworthy S, Lantier F. Protective effect of the T112 PrP variant in sheep challenged with bovine spongiform encephalopathy. J Gen Virol 2009; 90:2569-2574. [PMID: 19587133 DOI: 10.1099/vir.0.012724-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Sheep with an ARQ/ARQ PRNP genotype at codon positions 136/154/171 are highly susceptible to experimental infection with bovine spongiform encephalopathy (BSE). However, a number of sheep challenged orally or intracerebrally with BSE were clinically asymptomatic and found to survive or were diagnosed as BSE-negative when culled. Sequencing of the full PRNP gene open reading frame of BSE-susceptible and -resistant sheep indicated that, in the majority of Suffolk sheep, resistance was associated with an M112T PRNP variant (TARQ allele). A high proportion (47 of 49; 96%) of BSE-challenged wild-type (MARQ/MARQ) Suffolk sheep were BSE-infected, whereas none of the 20 sheep with at least one TARQ allele succumbed to BSE. Thirteen TARQ-carrying sheep challenged with BSE are still alive and some have survival periods equivalent to, or greater than, reported incubation periods of BSE in ARR/ARR and VRQ/VRQ sheep.
Collapse
Affiliation(s)
- G C Saunders
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency (VLA Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK
| | - I Lantier
- INRA, UR1282, Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France
| | - S Cawthraw
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency (VLA Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK
| | - P Berthon
- INRA, UR1282, Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France
| | - S J Moore
- Pathology Department, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - M E Arnold
- CERA, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - O Windl
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency (VLA Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK
| | - M M Simmons
- Pathology Department, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - O Andréoletti
- UMR INRA-ENVT, Interactions Hôtes-Agents Pathogènes, Ecole Vétérinaire de Toulouse, F-310761 Toulouse, France
| | - S Bellworthy
- Pathology Department, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - F Lantier
- INRA, UR1282, Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France
| |
Collapse
|
31
|
Laude H, Béringue V. [Newly discovered forms of prion diseases in ruminants]. PATHOLOGIE-BIOLOGIE 2009; 57:117-126. [PMID: 18848406 DOI: 10.1016/j.patbio.2008.07.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Accepted: 07/03/2008] [Indexed: 05/26/2023]
Abstract
Transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative diseases caused by unconventional agents, the prions. They are characterised by the accumulation in infected tissues of an abnormally folded form of the host-encoded prion protein (PrP). This pathological form is partially resistant to protease digestion, leading to the production of so-called PrP(res) fragments. Different isolates from the same host species may show different eletrophoretic profiles, reflecting the existence of different prion strains. The active surveillance of ruminant TSEs implemented in European countries, based on a large-scale biochemical testing of brain tissue samples from carcasses, has revealed PrP(res) profiles unnoticed so far. Experimental transmission of these atypical cases to various transgenic mouse lines has led to the recognition of a novel scrapie strain in sheep and goats, called Nor98, and of two variant strains of spongiform encephalopathy in cattle. This review is aimed at summarising the current knowledge on these newly recognised forms of ruminants TSEs, and at discussing their possible origin and potential implications in terms of animal and human health.
Collapse
Affiliation(s)
- H Laude
- INRA, U892, virologie immunologie moléculaires, domaine de Vilvert, 78350 Jouy-en-Josas, France.
| | | |
Collapse
|
32
|
Vaccari G, Scavia G, Sala M, Cosseddu G, Chiappini B, Conte M, Esposito E, Lorenzetti R, Perfetti G, Marconi P, Scholl F, Barbaro K, Bella A, Nonno R, Agrimi U. Protective effect of the AT137RQ and ARQK176 PrP allele against classical scrapie in Sarda breed sheep. Vet Res 2009; 40:19. [PMID: 19171116 PMCID: PMC2695041 DOI: 10.1051/vetres/2009002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Accepted: 01/22/2009] [Indexed: 12/03/2022] Open
Abstract
The susceptibility of sheep to scrapie is under the control of the host’s prion protein (PrP) gene and is also influenced by the strain of the agent. PrP polymorphisms at codons 136 (A/V), 154 (R/H) and 171 (Q/R/H) are the main determinants of susceptibility/resistance of sheep to classical scrapie. They are combined in four main variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programmes have been undertaken on this basis in the European Union and the USA to increase the frequency of the resistant ARR allele in sheep populations. Herein, we report the results of a multi-flock study showing the protective effect of polymorphisms other than those at codons 136, 154 and 171 in Sarda breed sheep. All ARQ/ARQ affected sheep (n = 154) and 378 negative ARQ/ARQ controls from four scrapie outbreaks were submitted to sequencing of the PrP gene. The distribution of variations other than those at the standard three codons, between scrapie cases and negative controls, was statistically different in all flocks. In particular, the AT137RQ and ARQK176 alleles showed a clear protective effect. This is the first study demonstrating a protective influence of alleles other than ARR under field conditions. If further investigations in other sheep breeds and with other scrapie sources confirm these findings, the availability of various protective alleles in breeding programmes of sheep for scrapie resistance could be useful in breeds with a low frequency of the ARR allele and would allow maintaining a wider variability of the PrP gene.
Collapse
|
33
|
Hickford JGH, Zhou H, Fang Q, Byun SO, Gong H. Frequency of PRNP genotypes in common New Zealand sheep breeds. Vet Rec 2008; 163:453-4. [PMID: 18849578 DOI: 10.1136/vr.163.15.453] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- J G H Hickford
- Gene-Marker Laboratory, Agriculture and Life Sciences Division, po Box 84, Lincoln University, Lincoln 7647, Canterbury, New Zealand
| | | | | | | | | |
Collapse
|
34
|
Genotyping of the prion protein (PrP) gene in Red Maasai and Black Head Persian sheep in Tanzania. Small Rumin Res 2008. [DOI: 10.1016/j.smallrumres.2008.07.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
35
|
Genetic variability at seven codons of the prion protein gene in nine Pakistani sheep breeds. J Genet 2008; 87:187-90. [DOI: 10.1007/s12041-008-0029-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
36
|
Abstract
Variation in the ovine prion protein amino acid sequence influences scrapie progression, with sheep homozygous for A(136)R(154)Q(171) considered susceptible. This study examined the association of survival time of scrapie-exposed ARQ sheep with variation elsewhere in the ovine prion gene. Four single nucleotide polymorphism alleles were associated with prolonged survival. One nonsynonymous allele (T112) was associated with an additional 687 days of survival for scrapie-exposed sheep compared to M112 sheep (odds ratio, 42.5; P = 0.00014). The only two sheep homozygous for T112 (TARQ) did not develop scrapie, suggesting that the allelic effect may be additive. These results provide evidence that TARQ sheep are genetically resistant to development of classical scrapie.
Collapse
|
37
|
Frequencies of PrP genotypes and their implication for breeding against scrapie susceptibility in nine Pakistani sheep breeds. Mol Biol Rep 2008; 36:561-5. [DOI: 10.1007/s11033-008-9214-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Accepted: 02/04/2008] [Indexed: 10/22/2022]
|
38
|
van Keulen LJM, Bossers A, van Zijderveld F. TSE pathogenesis in cattle and sheep. Vet Res 2008; 39:24. [PMID: 18258167 DOI: 10.1051/vetres:2007061] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 11/09/2007] [Indexed: 12/18/2022] Open
Abstract
Many studies have been undertaken in rodents to study the pathogenesis of transmissible spongiform encephalopathies (TSE). Only a few studies have focused on the pathogenesis of bovine spongiform encephalopathy (BSE) and scrapie in their natural hosts. In this review, we summarize the most recent insights into the pathogenesis of BSE and scrapie starting from the initial uptake of TSE agents and crossing of the gut epithelium. Following replication in the gut-associated lymphoid tissues (GALT), TSE agents spread to the enteric nervous system (ENS) of the gut. Infection is then carried through the efferent fibers of the post-ganglionic neurons of the parasympathetic and sympathetic nervous system to the pre-ganglionic neurons in the medulla oblongata of the brain and the thoracic segments of the spinal cord. The differences between the pathogenesis of BSE in cattle and scrapie in sheep are discussed as well as the possible existence of additional pathogenetic routes.
Collapse
Affiliation(s)
- Lucien J M van Keulen
- Department of Bacteriology and TSE's, Central Institute for animal Disease Control , Wageningen University and Research Centre, 8203 AA Lelystad, the Netherlands.
| | | | | |
Collapse
|
39
|
Lipsky S, Brandt H, Lühken G, Erhardt G. Analysis of prion protein genotypes in relation to reproduction traits in local and cosmopolitan German sheep breeds. Anim Reprod Sci 2008; 103:69-77. [PMID: 17204379 DOI: 10.1016/j.anireprosci.2006.12.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 11/29/2006] [Accepted: 12/04/2006] [Indexed: 11/27/2022]
Abstract
Due to the genetic determination of susceptibility to scrapie and other forms of transmissible spongiform encephalopathy (TSE) in sheep breeding to the less susceptible prion protein (PrP) genotype ARR/ARR was advanced within EU. In 4961 ewes of nine German sheep breeds (Coburg Fox sheep, Gray Horned Heath sheep, Merinoland sheep, Rhoen sheep, German Blackheaded Mutton sheep, Shropshire, Suffolk, Texel and White East Friesian Milk sheep) representing local and cosmopolitan breeds the reproductive traits number of lambs born, dead (including abortion at the end of pregnancy, stillbirth and death during the first 56 days post natum), weaned and rearing rate at each lambing were recorded and in 1641 of these ewes the PrP genotype was determined. A linear model was used to evaluate associations between PrP genotype and reproduction traits including the effects of PrP genotype (four classes: ewes with two, one and no copy of the ARR allele and with unknown PrP genotype), breed, interaction of PrP genotype and breed, number of lambing, lambing season and stock. Significant associations were only observed between the PrP genotype and the number of dead lambs at each lambing in Shropshire and Merinoland sheep and the rearing rate at each lambing in Shropshire. These significant associations were mainly caused by differences between animals with unknown PrP genotype and animals of the other PrP classes. In conclusion, breeding for TSE resistant sheep will not lead to a reduction in economically important reproduction traits.
Collapse
Affiliation(s)
- S Lipsky
- Department of Animal Breeding and Genetics, Justus-Liebig-University Giessen, Ludwigstrasse 21 b, 35390 Giessen, Germany
| | | | | | | |
Collapse
|
40
|
Groschup MH, Lacroux C, Buschmann A, Lühken G, Mathey J, Eiden M, Lugan S, Hoffmann C, Espinosa JC, Baron T, Torres JM, Erhardt G, Andreoletti O. Classic scrapie in sheep with the ARR/ARR prion genotype in Germany and France. Emerg Infect Dis 2007; 13:1201-7. [PMID: 17953092 PMCID: PMC2828083 DOI: 10.3201/eid1308.070077] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We report 2 natural scrapie cases in sheep carrying the ARR/ARR prion genotype, which is believed to confer resistance against classic scrapie and bovine spongiform encephalopathy. In the past, natural scrapie and bovine spongiform encephalopathy (BSE) infections have essentially not been diagnosed in sheep homozygous for the A136R154R171 haplotype of the prion protein. This genotype was therefore assumed to confer resistance to BSE and classic scrapie under natural exposure conditions. Hence, to exclude prions from the human food chain, massive breeding efforts have been undertaken in the European Union to amplify this gene. We report the identification of 2 natural scrapie cases in ARR/ARR sheep that have biochemical and transmission characteristics similar to cases of classic scrapie, although the abnormally folded prion protein (PrPSc) was associated with a lower proteinase-K resistance. PrPSc was clearly distinct from BSE prions passaged in sheep and from atypical scrapie prions. These findings strongly support the idea that scrapie prions are a mosaic of agents, which harbor different biologic properties, rather than a unique entity.
Collapse
Affiliation(s)
- Martin H Groschup
- Institute for Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Insel Riems, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Ekateriniadou L, Kanata E, Panagiotidis C, Nikolaou A, Koutsoukou E, Lymberopoulos A, Sklaviadis T. PrP genotypes in scrapie-affected sheep in Greece—The contribution of the AHQ 1 polymorphism. Small Rumin Res 2007. [DOI: 10.1016/j.smallrumres.2006.12.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
42
|
Benkel BF, Valle E, Bissonnette N, Hossain Farid A. Simultaneous detection of eight single nucleotide polymorphisms in the ovine prion protein gene. Mol Cell Probes 2007; 21:363-7. [PMID: 17590312 DOI: 10.1016/j.mcp.2007.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 04/23/2007] [Accepted: 05/01/2007] [Indexed: 10/23/2022]
Abstract
Amino acid polymorphisms in the prion protein gene (PrP) affect the susceptibility of sheep to scrapie, a transmissible spongiform encephalopathy (TSE). In particular, amino acid substitutions at codons 136, 154 and 171 of the ovine PrP gene are associated with different degrees of susceptibility to the classical form of scrapie, caused by 'typical' scrapie strains. Existing genotyping tests for scrapie susceptibility normally interrogate only the single nucleotide polymorphisms (SNPs) most relevant to 'typical' strains. Recently, however, a number of novel variants of the scrapie agent have been discovered. The ability of these new, 'atypical' scrapie variants to infect sheep that are resistant to 'typical' variants has raised concerns about the reduction in genetic variability that may result from intense selection for resistance to classical scrapie. Furthermore, a growing interest in a potential role for specific PrP genotypes in modulating performance traits is also driving a move toward more extensive characterization of haplotypes at the PrP locus. Here, we describe a single-tube method for the interrogation of eight SNPs within seven codons (112, 136, 141, 154, 171, 231 and 241) of the ovine PrP gene. This method is as accurate as sequencing, yet more affordable, and can easily be automated for high-throughput sample screening. Moreover, it can be modified to accommodate genetic variations that are found in local and heritage breeds.
Collapse
Affiliation(s)
- Bernhard F Benkel
- Department of Plant and Animal Sciences, Nova Scotia Agricultural College, Truro, NS, Canada B2N 5E3.
| | | | | | | |
Collapse
|
43
|
Lee CI, Yang Q, Perrier V, Baskakov IV. The dominant-negative effect of the Q218K variant of the prion protein does not require protein X. Protein Sci 2007; 16:2166-73. [PMID: 17766375 PMCID: PMC2204135 DOI: 10.1110/ps.072954607] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Previous studies identified several single-point mutants of the prion protein that displayed dominant-negative effects on prion replication. The dominant-negative effect was assumed to be mediated by protein X, an as-yet-unknown cellular cofactor that is believed to be essential for prion replication. To gain insight into the mechanism that underlies the dominant-negative phenomena, we evaluated the effect of the Q218K variant of full-length recombinant prion protein (Q218K rPrP), one of the dominant-negative mutants, on cell-free polymerization of wild-type rPrP into amyloid fibrils. We found that both Q218K and wild-type (WT) rPrPs were incorporated into fibrils when incubated as a mixture; however, the yield of polymerization was substantially decreased in the presence of Q218K rPrP. Furthermore, in contrast to fibrils produced from WT rPrP, the fibrils generated in the mixture of WT and Q218K rPrPs did not acquire the proteinase K-resistant core of 16 kDa that was shown previously to encompass residues 97-230 and was similar to that of PrP(Sc). Our studies demonstrate that the Q218K variant exhibits the dominant-negative effect in cell-free conversion in the absence of protein X, and that this effect is, presumably, mediated by physical interaction between Q218K and WT rPrP during the polymerization process.
Collapse
Affiliation(s)
- Cheng I Lee
- Medical Biotechnology Center, University of Maryland Biotechnology Institute, Baltimore, Maryland 21201, USA
| | | | | | | |
Collapse
|
44
|
Zhou H, Hickford JGH, Fang Q. Technical note: determination of alleles of the ovine PRNP gene using PCR-single-strand conformational polymorphism analysis. J Anim Sci 2007; 83:745-9. [PMID: 15753327 DOI: 10.2527/2005.834745x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Susceptibility to scrapie in sheep is linked to variation at codons 136, 154, and 171 in the host prion protein gene (PRNP). A number of techniques are available for detecting these polymorphisms, but none allow for a rapid and accurate determination of genotype. Here we describe PCR coupled with single-strand conformational polymorphism (SSCP) analysis, which allows for the accurate identification of ovine PRNP alleles. A gene region including codons 136 to 171 was amplified by PCR, and the amplimers were then denatured and subjected to electrophoresis in a nondenaturing polyacrylamide gel. Nine unique SSCP patterns, representing nine different alleles of the ovine PRNP gene, could be resolved. A new polymorphism (I/T) at codon 142 also was detected. The profiles produced by SSCP allowed for the accurate differentiation of PRNP alleles and could be employed to genotype PRNP in sheep.
Collapse
Affiliation(s)
- H Zhou
- Cell Biology Group, Agriculture and Life Sciences Division, Lincoln University, Canterbury, New Zealand
| | | | | |
Collapse
|
45
|
|
46
|
Takemura K, Kahdre M, Joseph D, Yousef A, Sreevatsan S. An overview of transmissible spongiform encephalopathies. Anim Health Res Rev 2007; 5:103-24. [PMID: 15984319 DOI: 10.1079/ahr200494] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
AbstractTransmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative disorders of humans and animals associated with an accumulation of abnormal isoforms of prion protein (PrP) in nerve cells. The pathogenesis of TSEs involves conformational conversions of normal cellular PrP (PrPc) to abnormal isoforms of PrP (PrPSc). While the protein-only hypothesis has been widely accepted as a causal mechanism of prion diseases, evidence from more recent research suggests a possible involvement of other cellular component(s) or as yet undefined infectious agent(s) in PrP pathogenesis. Although the underlying mechanisms of PrP strain variation and the determinants of interspecies transmissibility have not been fully elucidated, biochemical and molecular findings indicate that bovine spongiform encephalopathy in cattle and new-variant Creutzfeldt–Jakob disease in humans are caused by indistinguishable etiological agent(s). Cumulative evidence suggests that there may be risks of humans acquiring TSEs via a variety of exposures to infected material. The development of highly precise ligands is warranted to detect and differentiate strains, allelic variants and infectious isoforms of these PrPs. This article describes the general features of TSEs and PrP, the current understanding of their pathogenesis, recent advances in prion disease diagnostics, and PrP inactivation.
Collapse
Affiliation(s)
- K Takemura
- Food Animal Health Research Program, Department of Veterinary Preventive Medicine, Ohio Agricultural Research and Development Center, Ohio State University, Wooster, OH 44691, USA
| | | | | | | | | |
Collapse
|
47
|
Thackray A, Hopkins L, Bujdoso R. Proteinase K-sensitive disease-associated ovine prion protein revealed by conformation-dependent immunoassay. Biochem J 2007; 401:475-83. [PMID: 17018021 PMCID: PMC1820801 DOI: 10.1042/bj20061264] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PrPSc [abnormal disease-specific conformation of PrP (prion-related protein)] accumulates in prion-affected individuals in the form of amorphous aggregates. Limited proteolysis of PrPSc results in a protease-resistant core of PrPSc of molecular mass of 27-30 kDa (PrP27-30). Aggregated forms of PrP co-purify with prion infectivity, although infectivity does not always correlate with the presence of PrP27-30. This suggests that discrimination between PrPC (normal cellular PrP) and PrPSc by proteolysis may underestimate the repertoire and quantity of PrPSc subtypes. We have developed a CDI (conformation-dependent immunoassay) utilizing time-resolved fluorescence to study the conformers of disease-associated PrP in natural cases of sheep scrapie, without using PK (proteinase K) treatment to discriminate between PrPC and PrPSc. The capture-detector CDI utilizes N-terminal- and C-terminal-specific anti-PrP monoclonal antibodies that recognize regions of the prion protein differentially buried or exposed depending on the extent of denaturation of the molecule. PrPSc was precipitated from scrapie-infected brain stem and cerebellum tissue following sarkosyl extraction, with or without the use of sodium phosphotungstic acid, and native and denatured PrPSc detected by CDI. PrPSc was detectable in brain tissue from homozygous VRQ (V136 R154 Q171) and ARQ (A136 R154 Q171) scrapie-infected sheep brains. The highest levels of PrPSc were found in homozygous VRQ scrapie-infected brains. The quantity of PrPSc was significantly reduced, up to 90% in some cases, when samples were treated with PK prior to the CDI. Collectively, our results show that the level of PrPSc in brain samples from cases of natural scrapie display genotypic differences and that a significant amount of this material is PK-sensitive.
Collapse
Affiliation(s)
- Alana M. Thackray
- Centre for Veterinary Science, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES, U.K
| | - Lee Hopkins
- Centre for Veterinary Science, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES, U.K
| | - Raymond Bujdoso
- Centre for Veterinary Science, Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES, U.K
- To whom correspondence should be addressed (email )
| |
Collapse
|
48
|
OHARA J, TOGARI T, KUROKAWA A, MAEDA J, ISHIGURO N, FURUOKA H, HORIUCHI M. Frequencies of PrP Genotypes in Meat Breeds of Japanese Sheep and Trail of Selective Breeding in Experimental Sheep Flock. J Vet Med Sci 2007; 69:1325-9. [DOI: 10.1292/jvms.69.1325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Jiro OHARA
- Laboratory of Prion Diseases, Graduate School of Veterinary Medicine, Hokkaido University
| | - Tetsuro TOGARI
- Poultry and Sheep Research Unit, Hokkaido Animal Research Center
| | - Aya KUROKAWA
- Laboratory of Prion Diseases, Graduate School of Veterinary Medicine, Hokkaido University
| | - Junko MAEDA
- Laboratory of Prion Diseases, Graduate School of Veterinary Medicine, Hokkaido University
| | - Naotaka ISHIGURO
- Laboratory of Food and Environmental Hygiene, Faculty of Applied Biological Science, Gifu University
| | - Hidefumi FURUOKA
- Department of Pathological Science, Obihiro University of Agriculture and Veterinary Medicine
| | - Motohiro HORIUCHI
- Laboratory of Prion Diseases, Graduate School of Veterinary Medicine, Hokkaido University
| |
Collapse
|
49
|
Lühken G, Buschmann A, Brandt H, Eiden M, Groschup MH, Erhardt G. Epidemiological and genetical differences between classical and atypical scrapie cases. Vet Res 2006; 38:65-80. [PMID: 17156738 DOI: 10.1051/vetres:2006046] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Accepted: 09/13/2006] [Indexed: 11/15/2022] Open
Abstract
The aim of this study was to analyze the epidemiology and prion protein (PrP) genetics in scrapie-affected sheep flocks in Germany. For this purpose, 224 German scrapie cases in sheep diagnosed between January 2002 and February 2006 were classified as classical or atypical scrapie and the amino acids at codons 136, 141, 154 and 171 were determined. Likewise, representative numbers of flock mates were genotyped. Significant epidemiological differences were observed between classical and atypical scrapie cases in regard to the numbers of scrapie-affected sheep within a flock, the sizes of flocks with only a single scrapie-positive sheep or more than one scrapie-positive sheep and the age distribution of the scrapie-positive sheep. Sheep with the ARQ/ARQ genotype had by far the highest risk for acquiring classical scrapie, but the risk for atypical scrapie was the highest for sheep carrying phenylalanine (F) at position 141 (AF(141)RQ) and/or the AHQ haplotype. However, atypical scrapie also occurred with a notable frequency in sheep with the PrP haplotypes ARR and/or ARQ in combination with Leucine at position 141 (AL(141)RQ). Furthermore, six atypical scrapie-positive sheep carried the PrP genotype ARR/ARR. The high proportion of sheep flocks affected by atypical scrapie underscores the importance of this scrapie type.
Collapse
Affiliation(s)
- Gesine Lühken
- Department of Animal Breeding and Genetics, Justus-Liebig University of Giessen, 35390 Giessen, Germany.
| | | | | | | | | | | |
Collapse
|
50
|
Saunders GC, Cawthraw S, Mountjoy SJ, Hope J, Windl O. PrP genotypes of atypical scrapie cases in Great Britain. J Gen Virol 2006; 87:3141-3149. [PMID: 17030846 DOI: 10.1099/vir.0.81779-0] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Great Britain and elsewhere have detected atypical scrapie infection in sheep with PrP genotypes thought to be genetically resistant to the classical form of scrapie. DNA sequencing of the PrP gene of British atypical scrapie cases (n=69), classical scrapie cases (n=59) and scrapie-free controls (n=138) was undertaken to identify whether PrP variants, other than the three well-characterized polymorphic codons, influenced susceptibility to atypical scrapie infection. Four non-synonymous changes, M112T, M137T, L141F and P241S, were detected that are most probably associated with the A(136)R(154)Q(171) haplotype. Only the PrP variant containing a phenylalanine residue at amino acid position 141 was found to be associated more commonly with the atypical scrapie cases. In addition to the single nucleotide polymorphisms associated with the ARQ allele, two out of nine atypical scrapie cases with the ARR/ARR genotype were found to contain a 24 bp insertion, leading to an additional octapeptide repeat. In terms of PrP genetics, one classification of the GB scrapie cases examined in this study would place animals carrying any homozygous or heterozygous combination of ARR, AHQ or AF(141)RQ alleles, or any one of these alleles when paired with ARQ, as being susceptible to atypical scrapie infection, and animals heterozygous or homozygous for VRQ or homozygous for ARQ as being susceptible to classical scrapie disease. The AHQ PrP allele was associated with the highest incidence of atypical scrapie (263 per 100 000 alleles), whilst VRQ was associated with the lowest incidence (10 per 100 000 alleles).
Collapse
Affiliation(s)
- G C Saunders
- Department of TSE Molecular Biology, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - S Cawthraw
- Department of TSE Molecular Biology, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - S J Mountjoy
- Department of TSE Molecular Biology, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - J Hope
- Department of TSE Molecular Biology, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - O Windl
- Department of TSE Molecular Biology, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| |
Collapse
|