1
|
Ottina E, Panova V, Doglio L, Kazachenka A, Cornish G, Kirkpatrick J, Attig J, Young GR, Litchfield K, Lesluyes T, Van Loo P, Swanton C, MacRae J, Tüting T, Kassiotis G. E3 ubiquitin ligase HECTD2 mediates melanoma progression and immune evasion. Oncogene 2021; 40:5567-5578. [PMID: 34145398 PMCID: PMC8445817 DOI: 10.1038/s41388-021-01885-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 05/14/2021] [Accepted: 06/01/2021] [Indexed: 11/08/2022]
Abstract
The ubiquitin-proteasome system maintains protein homoeostasis, underpins the cell cycle, and is dysregulated in cancer. However, the role of individual E3 ubiquitin ligases, which mediate the final step in ubiquitin-mediated proteolysis, remains incompletely understood. Identified through screening for cancer-specific endogenous retroviral transcripts, we show that the little-studied E3 ubiquitin ligase HECTD2 exerts dominant control of tumour progression in melanoma. HECTD2 cell autonomously drives the proliferation of human and murine melanoma cells by accelerating the cell cycle. HECTD2 additionally regulates cancer cell production of immune mediators, initiating multiple immune suppressive pathways, which include the cyclooxygenase 2 (COX2) pathway. Accordingly, higher HECTD2 expression is associated with weaker anti-tumour immunity and unfavourable outcome of PD-1 blockade in human melanoma and counteracts immunity against a model tumour antigen in murine melanoma. This central, multifaceted role of HECTD2 in cancer cell-autonomous proliferation and in immune evasion may provide a single target for a multipronged therapy of melanoma.
Collapse
Affiliation(s)
- Eleonora Ottina
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
| | - Veera Panova
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
| | - Laura Doglio
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
| | | | - Georgina Cornish
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
| | | | - Jan Attig
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
| | - George R Young
- Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, London, UK
| | - Kevin Litchfield
- Cancer Evolution and Genome Instability Laboratory, The Francis Crick Institute, London, UK
| | - Tom Lesluyes
- Cancer Genomics Laboratory, The Francis Crick Institute, London, UK
| | - Peter Van Loo
- Cancer Genomics Laboratory, The Francis Crick Institute, London, UK
| | - Charles Swanton
- Cancer Evolution and Genome Instability Laboratory, The Francis Crick Institute, London, UK
| | - James MacRae
- Proteomics STP, The Francis Crick Institute, London, UK
| | - Thomas Tüting
- Laboratory of Experimental Dermatology, Department of Dermatology, University of Magdeburg, Magdeburg, Germany
| | - George Kassiotis
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK.
- Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, UK.
| |
Collapse
|
2
|
Singh S, Ng J, Sivaraman J. Exploring the "Other" subfamily of HECT E3-ligases for therapeutic intervention. Pharmacol Ther 2021; 224:107809. [PMID: 33607149 DOI: 10.1016/j.pharmthera.2021.107809] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 12/13/2020] [Accepted: 01/26/2021] [Indexed: 12/14/2022]
Abstract
The HECT E3 ligase family regulates key cellular signaling pathways, with its 28 members divided into three subfamilies: NEDD4 subfamily (9 members), HERC subfamily (6 members) and "Other" subfamily (13 members). Here, we focus on the less-explored "Other" subfamily and discuss the recent findings pertaining to their biological roles. The N-terminal regions preceding the conserved HECT domains are significantly diverse in length and sequence composition, and are mostly unstructured, except for short regions that incorporate known substrate-binding domains. In some of the better-characterized "Other" members (e.g., HUWE1, AREL1 and UBE3C), structure analysis shows that the extended region (~ aa 50) adjacent to the HECT domain affects the stability and activity of the protein. The enzymatic activity is also influenced by interactions with different adaptor proteins and inter/intramolecular interactions. Primarily, the "Other" subfamily members assemble atypical ubiquitin linkages, with some cooperating with E3 ligases from the other subfamilies to form branched ubiquitin chains on substrates. Viruses and pathogenic bacteria target and hijack the activities of "Other" subfamily members to evade host immune responses and cause diseases. As such, these HECT E3 ligases have emerged as potential candidates for therapeutic drug development.
Collapse
Affiliation(s)
- Sunil Singh
- Department of Biological Sciences, 14 Science Drive 4, National University of Singapore, 117543, Singapore
| | - Joel Ng
- Department of Biological Sciences, 14 Science Drive 4, National University of Singapore, 117543, Singapore
| | - J Sivaraman
- Department of Biological Sciences, 14 Science Drive 4, National University of Singapore, 117543, Singapore.
| |
Collapse
|
3
|
Bezsonov EE, Edskes HK, Wickner RB. Innate immunity to yeast prions: Btn2p and Cur1p curing of the [URE3] prion is prevented by 60S ribosomal protein deficiency or ubiquitin/proteasome system overactivity. Genetics 2021; 217:6127178. [PMID: 33857305 DOI: 10.1093/genetics/iyab013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/09/2021] [Indexed: 12/13/2022] Open
Abstract
[URE3] is an amyloid-based prion of Ure2p, a negative regulator of poor nitrogen source catabolism in Saccharomyces cerevisiae. Overproduced Btn2p or its paralog Cur1p, in processes requiring Hsp42, cure the [URE3] prion. Btn2p cures by collecting Ure2p amyloid filaments at one place in the cell. We find that rpl4aΔ, rpl21aΔ, rpl21bΔ, rpl11bΔ, and rpl16bΔ (large ribosomal subunit proteins) or ubr2Δ (ubiquitin ligase targeting Rpn4p, an activator of proteasome genes) reduce curing by overproduced Btn2p or Cur1p. Impaired curing in ubr2Δ or rpl21bΔ is restored by an rpn4Δ mutation. No effect of rps14aΔ or rps30bΔ on curing was observed, indicating that 60S subunit deficiency specifically impairs curing. Levels of Hsp42p, Sis1p, or Btn3p are unchanged in rpl4aΔ, rpl21bΔ, or ubr2Δ mutants. Overproduction of Cur1p or Btn2p was enhanced in rpn4Δ and hsp42Δ mutants, lower in ubr2Δ strains, and restored to above wild-type levels in rpn4Δ ubr2Δ strains. As in the wild-type, Ure2N-GFP colocalizes with Btn2-RFP in rpl4aΔ, rpl21bΔ, or ubr2Δ strains, but not in hsp42Δ. Btn2p/Cur1p overproduction cures [URE3] variants with low seed number, but seed number is not increased in rpl4aΔ, rpl21bΔ or ubr2Δ mutants. Knockouts of genes required for the protein sorting function of Btn2p did not affect curing of [URE3], nor did inactivation of the Hsp104 prion-curing activity. Overactivity of the ubiquitin/proteasome system, resulting from 60S subunit deficiency or ubr2Δ, may impair Cur1p and Btn2p curing of [URE3] by degrading Cur1p, Btn2p or another component of these curing systems.
Collapse
Affiliation(s)
- Evgeny E Bezsonov
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA
| | - Herman K Edskes
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA
| | - Reed B Wickner
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA
| |
Collapse
|
4
|
Wickner RB, Edskes HK, Son M, Wu S, Niznikiewicz M. How Do Yeast Cells Contend with Prions? Int J Mol Sci 2020; 21:ijms21134742. [PMID: 32635197 PMCID: PMC7369894 DOI: 10.3390/ijms21134742] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 06/26/2020] [Accepted: 06/30/2020] [Indexed: 12/11/2022] Open
Abstract
Infectious proteins (prions) include an array of human (mammalian) and yeast amyloid diseases in which a protein or peptide forms a linear β-sheet-rich filament, at least one functional amyloid prion, and two functional infectious proteins unrelated to amyloid. In Saccharomyces cerevisiae, at least eight anti-prion systems deal with pathogenic amyloid yeast prions by (1) blocking their generation (Ssb1,2, Ssz1, Zuo1), (2) curing most variants as they arise (Btn2, Cur1, Hsp104, Upf1,2,3, Siw14), and (3) limiting the pathogenicity of variants that do arise and propagate (Sis1, Lug1). Known mechanisms include facilitating proper folding of the prion protein (Ssb1,2, Ssz1, Zuo1), producing highly asymmetric segregation of prion filaments in mitosis (Btn2, Hsp104), competing with the amyloid filaments for prion protein monomers (Upf1,2,3), and regulation of levels of inositol polyphosphates (Siw14). It is hoped that the discovery of yeast anti-prion systems and elucidation of their mechanisms will facilitate finding analogous or homologous systems in humans, whose manipulation may be useful in treatment.
Collapse
|
5
|
Murugesan C, Manivannan P, Gangatharan M. Pros and cons in prion diseases abatement: Insights from nanomedicine and transmissibility patterns. Int J Biol Macromol 2020; 145:21-27. [PMID: 31866542 DOI: 10.1016/j.ijbiomac.2019.12.150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 09/27/2019] [Accepted: 12/17/2019] [Indexed: 12/29/2022]
Abstract
Ample research progress with nanotechnology applications in health and medicine implies precision and accuracy in the scenario of neurodegenerative disorders, for which impending research in ultimate and complete cure has been the vision worldwide. The complexity of prion disease has been unravelled by scientists and demarcated for efficient abatement protocols, but which are still under research and clinical trials. Drug delivery strategies combating prion diseases across the blood brain barrier, the efficacy of drugs and biocompatibility remain a serious question to be thoroughly studied for effective diagnosis and treatment. The present review compiles comprehensively the current treatment modalities against prion diseases and future prospects of nanotechnology addressing diagnosis and treatment of prion diseases with a special emphasis on transmissibility. Further, approaches for anti-prion technology, immunotherapy, and hindrances in vaccine development are discussed.
Collapse
Affiliation(s)
- Chandrasekaran Murugesan
- Department of Food Science and Biotechnology, 209 Neungdong-ro, Gwangjin-gu, Sejong University, Seoul 05006, Republic of Korea.
| | - Paramasivan Manivannan
- Department of Microbiology, Bharathidasan University, Tiruchirappalli 24, Tamilnadu, India
| | | |
Collapse
|
6
|
Attig J, Young GR, Hosie L, Perkins D, Encheva-Yokoya V, Stoye JP, Snijders AP, Ternette N, Kassiotis G. LTR retroelement expansion of the human cancer transcriptome and immunopeptidome revealed by de novo transcript assembly. Genome Res 2019; 29:1578-1590. [PMID: 31537638 PMCID: PMC6771403 DOI: 10.1101/gr.248922.119] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 08/21/2019] [Indexed: 12/30/2022]
Abstract
Dysregulated endogenous retroelements (EREs) are increasingly implicated in the initiation, progression, and immune surveillance of human cancer. However, incomplete knowledge of ERE activity limits mechanistic studies. By using pan-cancer de novo transcript assembly, we uncover the extent and complexity of ERE transcription. The current assembly doubled the number of previously annotated transcripts overlapping with long-terminal repeat (LTR) elements, several thousand of which were expressed specifically in one or a few related cancer types. Exemplified in melanoma, LTR-overlapping transcripts were highly predictable, disease prognostic, and closely linked with molecularly defined subtypes. They further showed the potential to affect disease-relevant genes, as well as produce novel cancer-specific antigenic peptides. This extended view of LTR elements provides the framework for functional validation of affected genes and targets for cancer immunotherapy.
Collapse
Affiliation(s)
- Jan Attig
- Retroviral Immunology, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - George R. Young
- Retrovirus-Host Interactions, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Louise Hosie
- Retroviral Immunology, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - David Perkins
- Mass Spectrometry Proteomics, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Vesela Encheva-Yokoya
- Mass Spectrometry Proteomics, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Jonathan P. Stoye
- Retrovirus-Host Interactions, The Francis Crick Institute, London NW1 1AT, United Kingdom;,Department of Medicine, Faculty of Medicine, Imperial College, London W2 1PG, United Kingdom
| | - Ambrosius P. Snijders
- Mass Spectrometry Proteomics, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Nicola Ternette
- The Jenner Institute, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - George Kassiotis
- Retroviral Immunology, The Francis Crick Institute, London NW1 1AT, United Kingdom;,Department of Medicine, Faculty of Medicine, Imperial College, London W2 1PG, United Kingdom
| |
Collapse
|
7
|
Abstract
Mammalian prion diseases are a group of neurodegenerative conditions caused by infection of the central nervous system with proteinaceous agents called prions, including sporadic, variant, and iatrogenic Creutzfeldt-Jakob disease; kuru; inherited prion disease; sheep scrapie; bovine spongiform encephalopathy; and chronic wasting disease. Prions are composed of misfolded and multimeric forms of the normal cellular prion protein (PrP). Prion diseases require host expression of the prion protein gene (PRNP) and a range of other cellular functions to support their propagation and toxicity. Inherited forms of prion disease are caused by mutation of PRNP, whereas acquired and sporadically occurring mammalian prion diseases are controlled by powerful genetic risk and modifying factors. Whereas some PrP amino acid variants cause the disease, others confer protection, dramatically altered incubation times, or changes in the clinical phenotype. Multiple mechanisms, including interference with homotypic protein interactions and the selection of the permissible prion strains in a host, play a role. Several non-PRNP factors have now been uncovered that provide insights into pathways of disease susceptibility or neurotoxicity.
Collapse
Affiliation(s)
- Simon Mead
- Medical Research Council Prion Unit at UCL, Institute of Prion Diseases, University College London, London W1W 7FF, United Kingdom;
| | - Sarah Lloyd
- Medical Research Council Prion Unit at UCL, Institute of Prion Diseases, University College London, London W1W 7FF, United Kingdom;
| | - John Collinge
- Medical Research Council Prion Unit at UCL, Institute of Prion Diseases, University College London, London W1W 7FF, United Kingdom;
| |
Collapse
|
8
|
Proteasomal Inhibition Redirects the PrP-Like Shadoo Protein to the Nucleus. Mol Neurobiol 2019; 56:7888-7904. [PMID: 31129810 PMCID: PMC6815274 DOI: 10.1007/s12035-019-1623-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 04/24/2019] [Indexed: 01/08/2023]
Abstract
The Shadoo protein (Sho) exhibits homology to the hydrophobic region of the cellular isoform of prion protein (PrPC). As prion-infected brains gradually accumulate infectivity-associated isoforms of prion protein (PrPSc), levels of mature endogenous Sho become reduced. To study the regulatory effect of the proteostatic network on Sho expression, we investigated the action of lactacystin, MG132, NH4Cl, and 3-methyladenine (3-MA) in two cell culture models. In primary mixed neuronal and glial cell cultures (MNGCs) from transgenic mice expressing wild-type Sho from the PrP gene promoter (Tg.Sprn mice), lactacystin- and MG132-mediated inhibition of proteasomal activity shifted the repertoire of Sho species towards unglycosylated forms appearing in the nuclei; conversely, the autophagic modulators NH4Cl and 3-MA did not affect Sho or PrPC glycosylation patterns. Mouse N2a neuroblastoma cells expressing Sho under control of a housekeeping gene promoter treated with MG132 or lactacystin also showed increased nuclear localization of unglycosylated Sho. As two proteasomal inhibitors tested in two cell paradigms caused redirection of Sho to nuclei at the expense of processing through the secretory pathway, our findings define a balanced shift in subcellular localization that thereby differs from the decreases in net Sho species seen in prion-infected brains. Our data are indicative of a physiological pathway to access Sho functions in the nucleus under conditions of impaired proteasomal activity. We also infer that these conditions would comprise a context wherein Sho’s N-terminal nucleic acid–binding RGG repeat region is brought into play.
Collapse
|
9
|
Puig B, Altmeppen HC, Glatzel M. Misfolding leads the way to unraveling signaling pathways in the pathophysiology of prion diseases. Prion 2017; 10:434-443. [PMID: 27870599 DOI: 10.1080/19336896.2016.1244593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
A misfolded version of the prion protein represents an essential component in the pathophysiology of fatal neurodegenerative prion diseases, which affect humans and animals alike. They may be of sporadic origin, acquired through exogenous introduction of infectious misfolded prion protein, or caused by genetic alterations in the prion protein coding gene. We have recently described a novel pathway linking retention of mutant prion protein in the early secretory pathway to activation p38-MAPK and a neurodegenerative phenotype in transgenic mice. Here we review the consequences that mutations in prion protein have on intracellular transport and stress responses focusing on protein quality control. We also discuss the neurotoxic signaling elicited by the accumulation of mutant prion protein in the endoplasmic reticulum and the Golgi apparatus. Improved knowledge about these processes will help us to better understand complex pathogenesis of prion diseases, a prerequisite for therapeutic strategies.
Collapse
Affiliation(s)
- Berta Puig
- a Institute of Neuropathology, University Medical Center Hamburg-Eppendorf , Hamburg , Germany
| | - Hermann C Altmeppen
- a Institute of Neuropathology, University Medical Center Hamburg-Eppendorf , Hamburg , Germany
| | - Markus Glatzel
- a Institute of Neuropathology, University Medical Center Hamburg-Eppendorf , Hamburg , Germany
| |
Collapse
|
10
|
Dugger BN, Perl DP, Carlson GA. Neurodegenerative Disease Transmission and Transgenesis in Mice. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a023549. [PMID: 28193724 DOI: 10.1101/cshperspect.a023549] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Although the discovery of the prion protein (PrP) resulted from its co-purification with scrapie infectivity in Syrian hamsters, work with genetically defined and genetically modified mice proved crucial for understanding the fundamental processes involved not only in prion diseases caused by PrP misfolding, aggregation, and spread but also in other, much more common, neurodegenerative brain diseases. In this review, we focus on methodological and conceptual approaches used to study scrapie and related PrP misfolding diseases in mice and how these approaches have advanced our understanding of related disorders including Alzheimer's and Parkinson's disease.
Collapse
Affiliation(s)
- Brittany N Dugger
- Institute for Neurodegenerative Diseases, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California 94158
| | - Daniel P Perl
- F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814
| | - George A Carlson
- Institute for Neurodegenerative Diseases, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California 94158.,McLaughlin Research Institute of Biomedical Sciences, Great Falls, Montana 59405
| |
Collapse
|
11
|
Carlson GA. Prion Protein and Genetic Susceptibility to Diseases Caused by Its Misfolding. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:123-145. [PMID: 28838658 DOI: 10.1016/bs.pmbts.2017.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Early genetic studies on scrapie, an infectious neurodegenerative disease of sheep that was adapted to mice, provided evidence in support of the hypothesis that the agent was a slow virus with a nucleic acid genome independent of the host. Particularly compelling support for an independent genome came from the existence of strains of scrapie agent, some of which were true breeding, while others appeared to mutate under selective pressure. Kuru, a neurodegenerative disease in the remote highlands of Papua New Guinea, had pathological changes similar to those in scrapie and also proved to be transmissible. Genetic studies with the tools of molecular biology and transgenic mice forced a reevaluation of earlier work and supported the prion hypothesis of a novel pathogen devoid of nucleic acid. In this chapter, I discuss the contributions of classical and molecular genetics to understanding PrP prion diseases and to determining that heritable information is enciphered in protein conformation.
Collapse
|
12
|
What's next for genomics and prion diseases? Future Sci OA 2017; 3:FSO188. [PMID: 28883991 PMCID: PMC5583649 DOI: 10.4155/fsoa-2017-0021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 02/21/2017] [Indexed: 02/03/2023] Open
|
13
|
Abstract
Prion diseases are unique neurodegenerative pathologies that can occur with sporadic, genetic, and acquired etiologies. Human and animal prion diseases can be recapitulated in laboratory animals with good reproducibility providing highly controlled models for studying molecular mechanisms of neurodegeneration. In this chapter the overall area of omics research in prion diseases is described. The term omics includes all fields of studies that employ a comprehensive, unbiased, and high-throughput approach to areas of research such as functional genomics, transcriptomics, and proteomics. These kind of approaches can be extremely helpful in identifying disease susceptibility factors and pathways that are dysregulated upon the onset and the progression of the disease. Herein, the most important research about the various forms of prion pathologies in human and in models of prion diseases in animals is presented and discussed.
Collapse
|
14
|
Deubiquitinating enzyme VCIP135 dictates the duration of botulinum neurotoxin type A intoxication. Proc Natl Acad Sci U S A 2017; 114:E5158-E5166. [PMID: 28584101 DOI: 10.1073/pnas.1621076114] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Botulism is characterized by flaccid paralysis, which can be caused by intoxication with any of the seven known serotypes of botulinum neurotoxin (BoNT), all of which disrupt synaptic transmission by endoproteolytic cleavage of SNARE proteins. BoNT serotype A (BoNT/A) has the most prolonged or persistent effects, which can last several months, and exerts its effects by specifically cleaving and inactivating SNAP25. A major factor contributing to the persistence of intoxication is the long half-life of the catalytic light chain, which remains enzymatically active months after entry into cells. Here we report that BoNT/A catalytic light chain binds to, and is a substrate for, the ubiquitin ligase HECTD2. However, the light chain evades proteasomal degradation by the dominant effect of a deubiquitinating enzyme, VCIP135/VCPIP1. This deubiquitinating enzyme binds BoNT/A light chain directly, with the two associating in cells through the C-terminal 77 amino acids of the light chain protease. The development of specific DUB inhibitors, together with inhibitors of BoNT/A proteolytic activity, may be useful for reducing the morbidity and public health costs associated with BoNT/A intoxication and could have potential biodefense implications.
Collapse
|
15
|
Sato M. Early Origin and Evolution of the Angelman Syndrome Ubiquitin Ligase Gene Ube3a. Front Cell Neurosci 2017; 11:62. [PMID: 28326016 PMCID: PMC5339648 DOI: 10.3389/fncel.2017.00062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 02/22/2017] [Indexed: 12/20/2022] Open
Abstract
The human Ube3a gene encodes an E3 ubiquitin ligase and exhibits brain-specific genomic imprinting. Genetic abnormalities that affect the maternal copy of this gene cause the neurodevelopmental disorder Angelman syndrome (AS), which is characterized by severe mental retardation, speech impairment, seizure, ataxia and some unique behavioral phenotypes. In this review article, I highlight the evolution of the Ube3a gene and its imprinting to provide evolutionary insights into AS. Recent comparative genomic studies have revealed that Ube3a is most phylogenetically similar to HECTD2 among the human HECT (homologous to the E6AP carboxyl terminus) family of E3 ubiquitin ligases, and its distant evolutionary origin can be traced to common ancestors of fungi and animals. Moreover, a gene more similar to Ube3a than HECTD2 is found in a range of eukaryotes from amoebozoans to basal metazoans, but is lost in later lineages. Unlike in mice and humans, Ube3a expression is biallelic in birds, monotremes, marsupials and insects. The imprinting domain that governs maternal expression of Ube3a was formed from non-imprinted elements following multiple chromosomal rearrangements after diversification of marsupials and placental mammals. Hence, the evolutionary origins of Ube3a date from long before the emergence of the nervous system, although its imprinted expression was acquired relatively recently. These observations suggest that exogenous expression and functional analyses of ancient Ube3a orthologs in mammalian neurons will facilitate the evolutionary understanding of AS.
Collapse
Affiliation(s)
- Masaaki Sato
- Graduate School of Science and Engineering and Brain and Body System Science Institute, Saitama UniversitySaitama, Japan
- RIKEN Brain Science InstituteWako, Japan
| |
Collapse
|
16
|
Mays CE, Soto C. The stress of prion disease. Brain Res 2016; 1648:553-560. [PMID: 27060771 DOI: 10.1016/j.brainres.2016.04.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 04/01/2016] [Accepted: 04/05/2016] [Indexed: 01/31/2023]
Abstract
Prion diseases are fatal neurodegenerative disorders that include scrapie of sheep, bovine spongiform encephalopathy of cattle, chronic wasting disease of cervids, and Creutzfeldt-Jakob disease (CJD) of humans. The etiology for prion diseases can be infectious, sporadic, or hereditary. However, the common denominator for all types is the formation of a transmissible agent composed of a β-sheet-rich, misfolded version of the host-encoded prion protein (PrPC), known as PrPSc. PrPSc self-replicates through a template-assisted process that converts the α-helical conformation of PrPC into the disease-associated isoform. In parallel with PrPSc accumulation, spongiform change is pathologically observed in the central nervous system, where "holes" appear because of massive neuronal death. Here, we review the cellular pathways triggered in response to PrPSc formation and accumulation. Available data suggest that neuronal dysfunction and death may be caused by what originates as a cellular pro-survival response to chronic PrPSc accumulation. We also discuss what is known about the complex cross-talk between the endoplasmic reticulum stress components and the quality control pathways. Better knowledge about these processes may lead to innovative therapeutic strategies based on manipulating the stress response and its consequences for neurodegeneration. This article is part of a Special Issue entitled SI:ER stress.
Collapse
Affiliation(s)
- Charles E Mays
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA
| | - Claudio Soto
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA.
| |
Collapse
|
17
|
Coon TA, McKelvey AC, Lear T, Rajbhandari S, Dunn SR, Connelly W, Zhao JY, Han S, Liu Y, Weathington NM, McVerry BJ, Zhang Y, Chen BB. The proinflammatory role of HECTD2 in innate immunity and experimental lung injury. Sci Transl Med 2016; 7:295ra109. [PMID: 26157031 DOI: 10.1126/scitranslmed.aab3881] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Invading pathogens may trigger overactivation of the innate immune system, which results in the release of large amounts of proinflammatory cytokines (cytokine storm) and leads to the development of pulmonary edema, multiorgan failure, and shock. PIAS1 is a multifunctional and potent anti-inflammatory protein that negatively regulates several key inflammatory pathways such as Janus kinase (JAK)-signal transducer and activator of transcription (STAT) and nuclear factor κB (NF-κB). We discovered a ubiquitin E3 ligase, HECTD2, which ubiquitinated and mediated the degradation of PIAS1, thus increasing inflammation in an experimental pneumonia model. We found that GSK3β phosphorylation of PIAS1 provided a phosphodegron for HECTD2 targeting. We also identified a mislocalized HECTD2 polymorphism, HECTD2(A19P), that was present in 8.5% of the population and functioned to reduce inflammation. This polymorphism prevented HECTD2/PIAS1 nuclear interaction, thus preventing PIAS1 degradation. The HECTD2(A19P) polymorphism was also protective toward acute respiratory distress syndrome (ARDS). We then developed a small-molecule inhibitor, BC-1382, that targeted HECTD2 and attenuated lipopolysaccharide (LPS)- and Pseudomonas aeruginosa-induced lung inflammation. These studies describe an unreported innate immune pathway and suggest that mutation or antagonism of the E3 ligase HECTD2 results in reduced severity of lung inflammation by selectively modulating the abundance of the anti-inflammatory protein PIAS1.
Collapse
Affiliation(s)
- Tiffany A Coon
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Alison C McKelvey
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Travis Lear
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Shristi Rajbhandari
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Sarah R Dunn
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - William Connelly
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Joe Y Zhao
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - SeungHye Han
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Yuan Liu
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Nathaniel M Weathington
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Bryan J McVerry
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Yingze Zhang
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Bill B Chen
- Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, PA 15213, USA. Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA.
| |
Collapse
|
18
|
Abstract
Transmissible spongiform encephalopathies (TSEs), or prion diseases, are fatal neurodegenerative disorders characterised by long incubation period, short clinical duration, and transmissibility to susceptible species. Neuronal loss, spongiform changes, gliosis and the accumulation in the brain of the misfolded version of a membrane-bound cellular prion protein (PrP(C)), termed PrP(TSE), are diagnostic markers of these diseases. Compelling evidence links protein misfolding and its accumulation with neurodegenerative changes. Accordingly, several mechanisms of prion-mediated neurotoxicity have been proposed. In this paper, we provide an overview of the recent knowledge on the mechanisms of neuropathogenesis, the neurotoxic PrP species and the possible therapeutic approaches to treat these devastating disorders.
Collapse
|
19
|
Hudson G, Uphill J, Hummerich H, Blevins J, Gambetti P, Zerr I, Collinge J, Mead S, Chinnery PF. Inherited mtDNA variations are not strong risk factors in human prion disease. Neurobiol Aging 2015; 36:2908.e1-3. [PMID: 26239179 DOI: 10.1016/j.neurobiolaging.2015.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 07/04/2015] [Indexed: 10/23/2022]
Abstract
Aside from variation in the prion protein gene, genetic risk factors for sporadic Creutzfeldt-Jakob disease remain elusive. Given emerging evidence implicating mitochondrial dysfunction in the pathogenesis of the disorders, we studied the role of inherited mitochondrial DNA variation in a 2255 sporadic prion disease cases and 3768 controls. Our analysis indicates that inherited mitochondrial DNA variation does not have a major role in the risk of developing the disorder.
Collapse
Affiliation(s)
- Gavin Hudson
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, UK
| | - James Uphill
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Holger Hummerich
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Janice Blevins
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Pierluigi Gambetti
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Inga Zerr
- Clinical Dementia Center, Department of Neurology, Georg-August University Göttingen, Göttingen, Germany; Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich Munich, Germany
| | - John Collinge
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Simon Mead
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.
| | - Patrick F Chinnery
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, UK
| |
Collapse
|
20
|
Buchner DA, Nadeau JH. Contrasting genetic architectures in different mouse reference populations used for studying complex traits. Genome Res 2015; 25:775-91. [PMID: 25953951 PMCID: PMC4448675 DOI: 10.1101/gr.187450.114] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 03/31/2015] [Indexed: 01/14/2023]
Abstract
Quantitative trait loci (QTLs) are being used to study genetic networks, protein functions, and systems properties that underlie phenotypic variation and disease risk in humans, model organisms, agricultural species, and natural populations. The challenges are many, beginning with the seemingly simple tasks of mapping QTLs and identifying their underlying genetic determinants. Various specialized resources have been developed to study complex traits in many model organisms. In the mouse, remarkably different pictures of genetic architectures are emerging. Chromosome Substitution Strains (CSSs) reveal many QTLs, large phenotypic effects, pervasive epistasis, and readily identified genetic variants. In contrast, other resources as well as genome-wide association studies (GWAS) in humans and other species reveal genetic architectures dominated with a relatively modest number of QTLs that have small individual and combined phenotypic effects. These contrasting architectures are the result of intrinsic differences in the study designs underlying different resources. The CSSs examine context-dependent phenotypic effects independently among individual genotypes, whereas with GWAS and other mouse resources, the average effect of each QTL is assessed among many individuals with heterogeneous genetic backgrounds. We argue that variation of genetic architectures among individuals is as important as population averages. Each of these important resources has particular merits and specific applications for these individual and population perspectives. Collectively, these resources together with high-throughput genotyping, sequencing and genetic engineering technologies, and information repositories highlight the power of the mouse for genetic, functional, and systems studies of complex traits and disease models.
Collapse
Affiliation(s)
- David A Buchner
- Department of Genetics and Genome Sciences, Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | - Joseph H Nadeau
- Pacific Northwest Diabetes Research Institute, Seattle, Washington 98122, USA
| |
Collapse
|
21
|
Lukic A, Uphill J, Brown CA, Beck J, Poulter M, Campbell T, Adamson G, Hummerich H, Whitfield J, Ponto C, Zerr I, Lloyd SE, Collinge J, Mead S. Rare structural genetic variation in human prion diseases. Neurobiol Aging 2015; 36:2004.e1-8. [PMID: 25726360 DOI: 10.1016/j.neurobiolaging.2015.01.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 12/22/2014] [Accepted: 01/13/2015] [Indexed: 10/24/2022]
Abstract
Prion diseases are a diverse group of neurodegenerative conditions, caused by the templated misfolding of prion protein. Aside from the strong genetic risk conferred by multiple variants of the prion protein gene (PRNP), several other variants have been suggested to confer risk in the most common type, sporadic Creutzfeldt-Jakob disease (sCJD) or in the acquired prion diseases. Large and rare copy number variants (CNVs) are known to confer risk in several related disorders including Alzheimer's disease (at APP), schizophrenia, epilepsy, mental retardation, and autism. Here, we report the first genome-wide analysis for CNV-associated risk using data derived from a recent international collaborative association study in sCJD (n = 1147 after quality control) and publicly available controls (n = 5427). We also investigated UK patients with variant Creutzfeldt-Jakob disease (n = 114) and elderly women from the Eastern Highlands of Papua New Guinea who proved highly resistant to the epidemic prion disease kuru, who were compared with healthy young Fore population controls (n = 395). There were no statistically significant alterations in the burden of CNVs >100, >500, or >1000 kb, duplications, or deletions in any disease group or geographic region. After correction for multiple testing, no statistically significant associations were found. A UK blood service control sample showed a duplication CNV that overlapped PRNP, but these were not found in prion disease. Heterozygous deletions of a 3' region of the PARK2 gene were found in 3 sCJD patients and no controls (p = 0.001, uncorrected). A cell-based prion infection assay did not provide supportive evidence for a role for PARK2 in prion disease susceptibility. These data are consistent with a modest impact of CNVs on risk of late-onset neurologic conditions and suggest that, unlike APP, PRNP duplication is not a causal high-risk mutation.
Collapse
Affiliation(s)
- Ana Lukic
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - James Uphill
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Craig A Brown
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - John Beck
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Mark Poulter
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Tracy Campbell
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Gary Adamson
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Holger Hummerich
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Jerome Whitfield
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Claudia Ponto
- Department of Neurology, Georg-August University Göttingen, Göttingen, Germany; German Center for Neurodegenrative Diseases (DZNE), Gottingen, Germany
| | - Inga Zerr
- Department of Neurology, Georg-August University Göttingen, Göttingen, Germany; German Center for Neurodegenrative Diseases (DZNE), Gottingen, Germany
| | - Sarah E Lloyd
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - John Collinge
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK
| | - Simon Mead
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.
| |
Collapse
|
22
|
Brown CA, Schmidt C, Poulter M, Hummerich H, Klöhn PC, Jat P, Mead S, Collinge J, Lloyd SE. In vitro screen of prion disease susceptibility genes using the scrapie cell assay. Hum Mol Genet 2014; 23:5102-8. [PMID: 24833721 PMCID: PMC4159154 DOI: 10.1093/hmg/ddu233] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 05/10/2014] [Indexed: 11/29/2022] Open
Abstract
Prion diseases (transmissible spongiform encephalopathies) are fatal neurodegenerative diseases, including Creutzfeldt-Jakob disease in humans, scrapie in sheep and bovine spongiform encephalopathy in cattle. While genome-wide association studies in human and quantitative trait loci mapping in mice have provided evidence for multiple susceptibility genes, few of these have been confirmed functionally. Phenotyping mouse models is generally the method of choice. However, this is not a feasible option where many novel genes, without pre-existing models, would need to be tested. We have therefore developed and applied an in-vitro screen to triage and prioritize candidate modifier genes for more detailed future studies which is faster, far more cost effective and ethical relative to mouse bioassay models. An in vitro prion bioassay, the scrapie cell assay, uses a neuroblastoma-derived cell line (PK1) that is susceptible to RML prions and able to propagate prions at high levels. In this study, we have generated stable gene silencing and/or overexpressing PK1-derived cell lines to test whether perturbation of 14 candidate genes affects prion susceptibility. While no consistent differences were determined for seven genes, highly significant changes were detected for Zbtb38, Sorcs1, Stmn2, Hspa13, Fkbp9, Actr10 and Plg, suggesting that they play key roles in the fundamental processes of prion propagation or clearance. Many neurodegenerative diseases involve the accumulation of misfolded protein aggregates and 'prion-like' seeding and spread has been implicated in their pathogenesis. It is therefore expected that some of these prion-modifier genes may be of wider relevance in neurodegeneration.
Collapse
Affiliation(s)
- Craig A Brown
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Christian Schmidt
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Mark Poulter
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Holger Hummerich
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Peter-C Klöhn
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Parmjit Jat
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Simon Mead
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - John Collinge
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Sarah E Lloyd
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| |
Collapse
|
23
|
Kumar P. Role of Oxidative Stress, ER Stress and Ubiquitin Proteasome System in Neurodegeneration. ACTA ACUST UNITED AC 2014. [DOI: 10.15406/mojcsr.2014.01.00010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
24
|
Zhu T, Hayat Khan S, Zhao D, Yang L. Regulation of proteasomes in prion disease. Acta Biochim Biophys Sin (Shanghai) 2014; 46:531-9. [PMID: 24829398 DOI: 10.1093/abbs/gmu031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The hallmark of prion disease is the accumulation of misfolded protein PrP(Sc), which is toxic to neuronal cells. The proteasome system is responsible for the rapid, precise, and timely degradation of proteins and plays an important role in cellular protein quality control. Increasing evidence indicates impaired activity of proteasomes in prion diseases. Accumulated PrP(Sc) can directly or indirectly affect proteasome activity. Misfolded protein may influence the assembly and activity of 19S regulatory particle, or post-translational modification of 20S proteasome, which may adversely affect the protein degradation activity of proteasomes. In this review, we summarized the recent findings concerning the possible regulation of proteasomes in prion and other neurodegenerative diseases. The proteasome system may enhance its degradation activity by changing its structure, and this activity can also be increased by related chaperones when neuronal cells are subject to stress. When the proteasome system is inhibited, degradation of protein aggregates via autophagy may increase as a compensatory system. It is possible that a balance exists between the proteasome and autophagy in vivo; when one is impaired, the activity of the other may increase to maintain homeostasis. However, more studies are needed to elucidate the relationship between the proteasome system and autophagy.
Collapse
Affiliation(s)
- Ting Zhu
- State Key Laboratories for Agrobiotechnology, Key Lab of Animal Epidemiology and Zoonosis, Ministry of Agriculture, National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Sher Hayat Khan
- State Key Laboratories for Agrobiotechnology, Key Lab of Animal Epidemiology and Zoonosis, Ministry of Agriculture, National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Deming Zhao
- State Key Laboratories for Agrobiotechnology, Key Lab of Animal Epidemiology and Zoonosis, Ministry of Agriculture, National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Lifeng Yang
- State Key Laboratories for Agrobiotechnology, Key Lab of Animal Epidemiology and Zoonosis, Ministry of Agriculture, National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| |
Collapse
|
25
|
Lee J, Kim SY, Hwang KJ, Ju YR, Woo HJ. Prion diseases as transmissible zoonotic diseases. Osong Public Health Res Perspect 2014; 4:57-66. [PMID: 24159531 PMCID: PMC3747681 DOI: 10.1016/j.phrp.2012.12.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 12/20/2012] [Accepted: 12/21/2012] [Indexed: 11/18/2022] Open
Abstract
Prion diseases, also called transmissible spongiform encephalopathies (TSEs), lead to neurological dysfunction in animals and are fatal. Infectious prion proteins are causative agents of many mammalian TSEs, including scrapie (in sheep), chronic wasting disease (in deer and elk), bovine spongiform encephalopathy (BSE; in cattle), and Creutzfeldt-Jakob disease (CJD; in humans). BSE, better known as mad cow disease, is among the many recently discovered zoonotic diseases. BSE cases were first reported in the United Kingdom in 1986. Variant CJD (vCJD) is a disease that was first detected in 1996, which affects humans and is linked to the BSE epidemic in cattle. vCJD is presumed to be caused by consumption of contaminated meat and other food products derived from affected cattle. The BSE epidemic peaked in 1992 and decreased thereafter; this decline is continuing sharply owing to intensive surveillance and screening programs in the Western world. However, there are still new outbreaks and/or progression of prion diseases, including atypical BSE, and iatrogenic CJD and vCJD via organ transplantation and blood transfusion. This paper summarizes studies on prions, particularly on prion molecular mechanisms, BSE, vCJD, and diagnostic procedures. Risk perception and communication policies of the European Union for the prevention of prion diseases are also addressed to provide recommendations for appropriate government policies in Korea.
Collapse
Affiliation(s)
- Jeongmin Lee
- Laboratory of Immunology, College of Veterinary Medicine, Seoul National University, Seoul,
Korea
- Division of Zoonoses, Korea National Institute of Health, Osong,
Korea
| | - Su Yeon Kim
- Division of Zoonoses, Korea National Institute of Health, Osong,
Korea
| | - Kyu Jam Hwang
- Division of Zoonoses, Korea National Institute of Health, Osong,
Korea
| | - Young Ran Ju
- Division of Zoonoses, Korea National Institute of Health, Osong,
Korea
| | - Hee-Jong Woo
- Laboratory of Immunology, College of Veterinary Medicine, Seoul National University, Seoul,
Korea
- Corresponding author. E-mail:
| |
Collapse
|
26
|
Haïk S, Brandel JP. Infectious prion diseases in humans: cannibalism, iatrogenicity and zoonoses. INFECTION GENETICS AND EVOLUTION 2014; 26:303-12. [PMID: 24956437 DOI: 10.1016/j.meegid.2014.06.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 06/10/2014] [Accepted: 06/13/2014] [Indexed: 12/24/2022]
Abstract
In contrast with other neurodegenerative disorders associated to protein misfolding, human prion diseases include infectious forms (also called transmitted forms) such as kuru, iatrogenic Creutzfeldt-Jakob disease and variant Creutzfeldt-Jakob disease. The transmissible agent is thought to be solely composed of the abnormal isoform (PrP(Sc)) of the host-encoded prion protein that accumulated in the central nervous system of affected individuals. Compared to its normal counterpart, PrP(Sc) is β-sheet enriched and aggregated and its propagation is based on an autocatalytic conversion process. Increasing evidence supports the view that conformational variations of PrP(Sc) encoded the biological properties of the various prion strains that have been isolated by transmission studies in experimental models. Infectious forms of human prion diseases played a pivotal role in the emergence of the prion concept and in the characterization of the very unconventional properties of prions. They provide a unique model to understand how prion strains are selected and propagate in humans. Here, we review and discuss how genetic factors interplay with strain properties and route of transmission to influence disease susceptibility, incubation period and phenotypic expression in the light of the kuru epidemics due to ritual endocannibalism, the various series iatrogenic diseases secondary to extractive growth hormone treatment or dura mater graft and the epidemics of variant Creutzfeldt-Jakob disease linked to dietary exposure to the agent of bovine spongiform encephalopathy.
Collapse
Affiliation(s)
- Stéphane Haïk
- Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Inserm, U 1127, CNRS UMR 7225, ICM, F-75013 Paris, France; AP-HP, Groupe hospitalier Pitié-Salpêtrière, Cellule Nationale de Référence des Maladies de Creutzfeldt-Jakob, F-75013 Paris, France; Centre National de Référence des Agents Transmissibles Non Conventionnels, F-75013 Paris, France.
| | - Jean-Philippe Brandel
- Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Inserm, U 1127, CNRS UMR 7225, ICM, F-75013 Paris, France; AP-HP, Groupe hospitalier Pitié-Salpêtrière, Cellule Nationale de Référence des Maladies de Creutzfeldt-Jakob, F-75013 Paris, France; Centre National de Référence des Agents Transmissibles Non Conventionnels, F-75013 Paris, France
| |
Collapse
|
27
|
Marbiah MM, Harvey A, West BT, Louzolo A, Banerjee P, Alden J, Grigoriadis A, Hummerich H, Kan HM, Cai Y, Bloom GS, Jat P, Collinge J, Klöhn PC. Identification of a gene regulatory network associated with prion replication. EMBO J 2014; 33:1527-47. [PMID: 24843046 PMCID: PMC4198050 DOI: 10.15252/embj.201387150] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Prions consist of aggregates of abnormal conformers of the cellular prion protein (PrPC). They propagate by recruiting host-encoded PrPC although the critical interacting proteins and the reasons for the differences in susceptibility of distinct cell lines and populations are unknown. We derived a lineage of cell lines with markedly differing susceptibilities, unexplained by PrPC expression differences, to identify such factors. Transcriptome analysis of prion-resistant revertants, isolated from highly susceptible cells, revealed a gene expression signature associated with susceptibility and modulated by differentiation. Several of these genes encode proteins with a role in extracellular matrix (ECM) remodelling, a compartment in which disease-related PrP is deposited. Silencing nine of these genes significantly increased susceptibility. Silencing of Papss2 led to undersulphated heparan sulphate and increased PrPC deposition at the ECM, concomitantly with increased prion propagation. Moreover, inhibition of fibronectin 1 binding to integrin α8 by RGD peptide inhibited metalloproteinases (MMP)-2/9 whilst increasing prion propagation. In summary, we have identified a gene regulatory network associated with prion propagation at the ECM and governed by the cellular differentiation state.
Collapse
Affiliation(s)
- Masue M Marbiah
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| | - Anna Harvey
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| | - Billy T West
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| | - Anais Louzolo
- Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - Priya Banerjee
- Biomedical Communications, Terrence Donnelly Health Sciences Complex University of Toronto, Toronto, ON, Canada
| | - Jack Alden
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| | - Anita Grigoriadis
- Breakthrough Breast Cancer Research Unit, Research Oncology, Guy's Hospital, London, UK
| | - Holger Hummerich
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| | - Ho-Man Kan
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Ying Cai
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - George S Bloom
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Parmjit Jat
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| | - John Collinge
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| | - Peter-Christian Klöhn
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK
| |
Collapse
|
28
|
Abstract
Human prion diseases are fatal neurodegenerative disorders that are characterized by spongiform changes, astrogliosis, and the accumulation of an abnormal prion protein (PrP(Sc)). Approximately 10%-15% of human prion diseases are familial variants that are caused by pathogenic mutations in the prion protein gene (PRNP). Point mutations or the insertions of one or more copies of a 24 bp repeat are associated with familial human prion diseases including familial Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome, and fatal familial insomnia. These mutations vary significantly in frequency between countries. Here, we compare the frequency of PRNP mutations between European countries and East Asians. Associations between single nucleotide polymorphisms (SNPs) of several candidate genes including PRNP and CJD have been reported. The SNP of PRNP at codon 129 has been shown to be associated with sporadic, iatrogenic, and variant CJD. The SNPs of several genes other than PRNP have been showed contradictory results. Case-control studies and genome-wide association studies have also been performed to identify candidate genes correlated with variant and/or sporadic CJD. This review provides a general overview of the genetic mutations and polymorphisms that have been analyzed in association with human prion diseases to date.
Collapse
Affiliation(s)
- Byung-Hoon Jeong
- Korea Zoonosis Research Institute, Chonbuk National University, Jeonju, Korea
| | - Yong-Sun Kim
- Ilsong Institute of Life Science, Hallym University, Anyang, Korea
| |
Collapse
|
29
|
Jackson GS, Burk-Rafel J, Edgeworth JA, Sicilia A, Abdilahi S, Korteweg J, Mackey J, Thomas C, Wang G, Schott JM, Mummery C, Chinnery PF, Mead S, Collinge J. Population screening for variant Creutzfeldt-Jakob disease using a novel blood test: diagnostic accuracy and feasibility study. JAMA Neurol 2014; 71:421-8. [PMID: 24590363 PMCID: PMC4158718 DOI: 10.1001/jamaneurol.2013.6001] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
IMPORTANCE Our study indicates a prototype blood-based variant Creutzfeldt-Jakob disease (vCJD) assay has sufficient sensitivity and specificity to justify a large study comparing vCJD prevalence in the United Kingdom with a bovine spongiform encephalopathy-unexposed population. In a clinical diagnostic capacity, the assay's likelihood ratios dramatically change an individual's pretest disease odds to posttest probabilities and can confirm vCJD infection. OBJECTIVES To determine the diagnostic accuracy of a prototype blood test for vCJD and hence its suitability for clinical use and for screening prion-exposed populations. DESIGN, SETTING, AND PARTICIPANTS Retrospective, cross-sectional diagnostic study of blood samples from national blood collection and prion disease centers in the United States and United Kingdom. Anonymized samples were representative of the US blood donor population (n = 5000), healthy UK donors (n = 200), patients with nonprion neurodegenerative diseases (n = 352), patients in whom a prion disease diagnosis was likely (n = 105), and patients with confirmed vCJD (n = 10). MAIN OUTCOME AND MEASURE Presence of vCJD infection determined by a prototype test (now in clinical diagnostic use) that captures, enriches, and detects disease-associated prion protein from whole blood using stainless steel powder. RESULTS The assay's specificity among the presumed negative American donor samples was 100% (95% CI, 99.93%-100%) and was confirmed in a healthy UK cohort (100% specificity; 95% CI, 98.2%-100%). Of potentially cross-reactive blood samples from patients with nonprion neurodegenerative diseases, no samples tested positive (100% specificity; 95% CI, 98.9%-100%). Among National Prion Clinic referrals in whom a prion disease diagnosis was likely, 2 patients with sporadic CJD tested positive (98.1% specificity; 95% CI, 93.3%-99.8%). Finally, we reconfirmed but could not refine our previous sensitivity estimate in a small blind panel of samples from unaffected individuals and patients with vCJD (70% sensitivity; 95% CI, 34.8%-93.3%). CONCLUSIONS AND RELEVANCE In conjunction with the assay's established high sensitivity (71.4%; 95% CI, 47.8%-88.7%), the extremely high specificity supports using the assay to screen for vCJD infection in prion-exposed populations. Additionally, the lack of cross-reactivity and false positives in a range of nonprion neurodegenerative diseases supports the use of the assay in patient diagnosis.
Collapse
Affiliation(s)
- Graham S Jackson
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Jesse Burk-Rafel
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England2currently with University of Michigan Medical School, Ann Arbor
| | - Julie Ann Edgeworth
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Anita Sicilia
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Sabah Abdilahi
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Justine Korteweg
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Jonathan Mackey
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Claire Thomas
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Guosu Wang
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Jonathan M Schott
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Catherine Mummery
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England
| | - Patrick F Chinnery
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, England
| | - Simon Mead
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England5National Prion Clinic, National Hospital for Neurology and Neurosurgery, Queen Square, London, England
| | - John Collinge
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, England5National Prion Clinic, National Hospital for Neurology and Neurosurgery, Queen Square, London, England
| |
Collapse
|
30
|
Jeong BH, Kim HJ, Lee KH, Carp RI, Kim YS. RARB and STMN2 polymorphisms are not associated with sporadic Creutzfeldt-Jakob disease (CJD) in the Korean population. Mol Biol Rep 2014; 41:2389-95. [PMID: 24414001 DOI: 10.1007/s11033-014-3093-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 01/04/2014] [Indexed: 11/26/2022]
Abstract
Polymorphisms in the prion protein gene (PRNP) can affect the susceptibility of humans to prion diseases. Recently, aside from PRNP, single nucleotide polymorphisms (SNPs) of two candidate genes for susceptibility to human prion diseases have been identified by human genome-wide association studies (GWAS) in the British population. One SNP of retinoic acid receptor beta (RARB), which is correlated with prion disease incubation time in mice, was associated with human prion diseases such as variant and iatrogenic CJD in the British population. The other SNP of the gene that encodes SCG10 (STMN2), which is related to clinical onset of sporadic CJD, was also associated with variant CJD and kuru. In order to investigate whether two polymorphisms located in upstream of RARB and STMN2 are associated with sporadic CJD in the Korean population, we compared genotype and allele frequencies of these polymorphisms in 217 sporadic CJD patients and 216 healthy Koreans. The genotype distribution and allele frequencies in upstream of the RARB and STMN2 polymorphisms were not significantly different between healthy controls and Korean sporadic CJD patients. This finding indicates that the two SNPs are not correlated with genetic susceptibility to sporadic CJD in the Korean population. This is the first genetic association study of RARB and STMN2 with sporadic CJD in an Asian population.
Collapse
Affiliation(s)
- Byung-Hoon Jeong
- Ilsong Institute of Life Science, Hallym University, 1605-4 Gwanyang-dong Dongan-gu, Anyang, Gyeonggi-do, 431-060, Republic of Korea
| | | | | | | | | |
Collapse
|
31
|
Lin Z, Zhao D, Yang L. Interaction between misfolded PrP and the ubiquitin-proteasome system in prion-mediated neurodegeneration. Acta Biochim Biophys Sin (Shanghai) 2013; 45:477-84. [PMID: 23449072 DOI: 10.1093/abbs/gmt020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Prion diseases are associated with the conformational conversion of cellular prion protein (PrP(C)) to pathological β-sheet isoforms (PrP(Sc)), which is the infectious agent beyond comprehension. Increasing evidence indicated that an unknown toxic gain of function of PrP(sc) underlies neuronal death. Conversely, strong evidence indicated that cellular prion protein might be directly cytotoxic by mediating neurotoxic signaling of β-sheet-rich conformers independent of prion replication. Furthermore, the common properties of β-sheet-rich isoform such as PrP(Sc) and β amyloid protein become the lynchpin that interprets the general pathological mechanism of protein misfolding diseases. Dysfunction of the ubiquitin-proteasome system (UPS) has been implicated in various protein misfolding diseases. However, the mechanisms of this impairment remain unknown in many cases. In prion disease, prion-infected mouse brains have increased levels of ubiquitin conjugates, which correlate with decreased proteasome function. Both PrP(C) and PrP(Sc) accumulate in cells after proteasome inhibition, which leads to increased cell death. A direct interaction between 20S core particle and PrP isoforms was demonstrated. Here we review the ability of misfolded PrP and UPS to affect each other, which might contribute to the pathological features of prion-mediated neurodegeneration.
Collapse
Affiliation(s)
- Zhu Lin
- State Key Laboratories for Agrobiotechnology, National Animal Transmissible Spongiform Encephalopathy Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | | | | |
Collapse
|
32
|
Lloyd SE, Mead S, Collinge J. Genetics of prion diseases. Curr Opin Genet Dev 2013; 23:345-51. [PMID: 23518043 PMCID: PMC3705206 DOI: 10.1016/j.gde.2013.02.012] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 02/18/2013] [Accepted: 02/18/2013] [Indexed: 01/08/2023]
Abstract
Prion diseases are transmissible, fatal neurodegenerative diseases that include scrapie and bovine spongiform encephalopathy (BSE) in animals and Creutzfeldt-Jakob disease (CJD) in human. The prion protein gene (PRNP) is the major genetic determinant of susceptibility, however, several studies now suggest that other genes are also important. Two recent genome wide association studies in human have identified four new loci of interest: ZBTB38-RASA2 in UK CJD cases and MTMR7 and NPAS2 in variant CJD. Complementary studies in mouse have used complex crosses to identify new modifiers such as Cpne8 and provided supporting evidence for previously implicated genes (Rarb and Stmn2). Expression profiling has identified new candidates, including Hspa13, which reduces incubation time in a transgenic model.
Collapse
Affiliation(s)
- Sarah E Lloyd
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, London, WC1N 3BG, UK
| | | | | |
Collapse
|
33
|
Basu U, Guan LL, Moore SS. Functional genomics approach for identification of molecular processes underlying neurodegenerative disorders in prion diseases. Curr Genomics 2013; 13:369-78. [PMID: 23372423 PMCID: PMC3401894 DOI: 10.2174/138920212801619223] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/30/2012] [Accepted: 05/30/2012] [Indexed: 12/11/2022] Open
Abstract
Prion diseases or transmissible spongiform encephalopathies (TSEs) are infectious neurodegenerative disorders leading to death. These include Cresutzfeldt-Jakob disease (CJD), familial, sporadic and variant CJD and kuru in humans; and animal TSEs include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, chronic wasting disease (CWD) of mule deer and elk, and transmissible mink encephalopathy. All these TSEs share common pathological features such as accumulation of mis-folded prion proteins in the central nervous system leading to cellular dysfunction and cell death. It is important to characterize the molecular pathways and events leading to prion induced neurodegeneration. Here we discuss the impact of the functional genomics approaches including microarrays, subtractive hybridization and microRNA profiling in elucidating transcriptional cascades at different stages of disease. Many of these transcriptional changes have been observed in multiple neurodegenerative diseases which may aid in identification of biomarkers for disease. A comprehensive characterization of expression profiles implicated in neurodegenerative disorders will undoubtedly advance our understanding on neuropathology and dysfunction during prion disease and other neurodegenerative disorders. We also present an outlook on the future work which may focus on analysis of structural genetic variation, genome and transcriptome sequencing using next generation sequencing with an integrated approach on animal and human TSE related studies.
Collapse
Affiliation(s)
- Urmila Basu
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada T6G 2P5
| | | | | |
Collapse
|
34
|
Sod1 deficiency reduces incubation time in mouse models of prion disease. PLoS One 2013; 8:e54454. [PMID: 23349894 PMCID: PMC3551847 DOI: 10.1371/journal.pone.0054454] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 12/11/2012] [Indexed: 11/19/2022] Open
Abstract
Prion infections, causing neurodegenerative conditions such as Creutzfeldt-Jakob disease and kuru in humans, scrapie in sheep and BSE in cattle are characterised by prolonged and variable incubation periods that are faithfully reproduced in mouse models. Incubation time is partly determined by genetic factors including polymorphisms in the prion protein gene. Quantitative trait loci studies in mice and human genome-wide association studies have confirmed that multiple genes are involved. Candidate gene approaches have also been used and identified App, Il1-r1 and Sod1 as affecting incubation times. In this study we looked for an association between App, Il1-r1 and Sod1 representative SNPs and prion disease incubation time in the Northport heterogeneous stock of mice inoculated with the Chandler/RML prion strain. No association was seen with App, however, significant associations were seen with Il1-r1 (P = 0.02) and Sod1 (P<0.0001) suggesting that polymorphisms at these loci contribute to the natural variation observed in incubation time. Furthermore, following challenge with Chandler/RML, ME7 and MRC2 prion strains, Sod1 deficient mice showed highly significant reductions in incubation time of 20, 13 and 24%, respectively. No differences were detected in Sod1 expression or activity. Our data confirm the protective role of endogenous Sod1 in prion disease.
Collapse
|
35
|
Saba R, Booth S. The Genetics of Susceptibility to Variant Creutzfeldt-Jakob Disease. Public Health Genomics 2013; 16:17-24. [DOI: 10.1159/000345203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
36
|
Grau-Bové X, Sebé-Pedrós A, Ruiz-Trillo I. A genomic survey of HECT ubiquitin ligases in eukaryotes reveals independent expansions of the HECT system in several lineages. Genome Biol Evol 2013; 5:833-47. [PMID: 23563970 PMCID: PMC3673628 DOI: 10.1093/gbe/evt052] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2013] [Indexed: 12/19/2022] Open
Abstract
The posttranslational modification of proteins by the ubiquitination pathway is an important regulatory mechanism in eukaryotes. To date, however, studies on the evolutionary history of the proteins involved in this pathway have been restricted to E1 and E2 enzymes, whereas E3 studies have been focused mainly in metazoans and plants. To have a wider perspective, here we perform a genomic survey of the HECT family of E3 ubiquitin-protein ligases, an important part of this posttranslational pathway, in genomes from representatives of all major eukaryotic lineages. We classify eukaryotic HECTs and reconstruct, by phylogenetic analysis, the putative repertoire of these proteins in the last eukaryotic common ancestor (LECA). Furthermore, we analyze the diversity and complexity of protein domain architectures of HECTs along the different extant eukaryotic lineages. Our data show that LECA had six different HECTs and that protein expansion and N-terminal domain diversification shaped HECT evolution. Our data reveal that the genomes of animals and unicellular holozoans considerably increased the molecular and functional diversity of their HECT system compared with other eukaryotes. Other eukaryotes, such as the Apusozoa Thecanomas trahens or the Heterokonta Phytophthora infestans, independently expanded their HECT repertoire. In contrast, plant, excavate, rhodophyte, chlorophyte, and fungal genomes have a more limited enzymatic repertoire. Our genomic survey and phylogenetic analysis clarifies the origin and evolution of different HECT families among eukaryotes and provides a useful phylogenetic framework for future evolutionary studies of this regulatory pathway.
Collapse
Affiliation(s)
- Xavier Grau-Bové
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Catalonia, Spain
| | - Arnau Sebé-Pedrós
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Catalonia, Spain
| | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Barcelona, Catalonia, Spain
- Departament de Genètica, Universitat de Barcelona, Catalonia, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Catalonia, Spain
| |
Collapse
|
37
|
Grizenkova J, Akhtar S, Hummerich H, Tomlinson A, Asante EA, Wenborn A, Fizet J, Poulter M, Wiseman FK, Fisher EMC, Tybulewicz VLJ, Brandner S, Collinge J, Lloyd SE. Overexpression of the Hspa13 (Stch) gene reduces prion disease incubation time in mice. Proc Natl Acad Sci U S A 2012; 109:13722-7. [PMID: 22869728 PMCID: PMC3427081 DOI: 10.1073/pnas.1208917109] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Prion diseases are fatal neurodegenerative disorders that include bovine spongiform encephalopathy (BSE) and scrapie in animals and Creutzfeldt-Jakob disease (CJD) in humans. They are characterized by long incubation periods, variation in which is determined by many factors including genetic background. In some cases it is possible that incubation time may be directly correlated to the level of gene expression. To test this hypothesis, we combined incubation time data from five different inbred lines of mice with quantitative gene expression profiling in normal brains and identified five genes with expression levels that correlate with incubation time. One of these genes, Hspa13 (Stch), is a member of the Hsp70 family of ATPase heat shock proteins, which have been previously implicated in prion propagation. To test whether Hspa13 plays a causal role in determining the incubation period, we tested two overexpressing mouse models. The Tc1 human chromosome 21 (Hsa21) transchromosomic mouse model of Down syndrome is trisomic for many Hsa21 genes including Hspa13 and following Chandler/Rocky Mountain Laboratory (RML) prion inoculation, shows a 4% reduction in incubation time. Furthermore, a transgenic model with eightfold overexpression of mouse Hspa13 exhibited highly significant reductions in incubation time of 16, 15, and 7% following infection with Chandler/RML, ME7, and MRC2 prion strains, respectively. These data further implicate Hsp70-like molecular chaperones in protein misfolding disorders such as prion disease.
Collapse
Affiliation(s)
- Julia Grizenkova
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Shaheen Akhtar
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Holger Hummerich
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Andrew Tomlinson
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Emmanuel A. Asante
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Adam Wenborn
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Jérémie Fizet
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Mark Poulter
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Frances K. Wiseman
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Elizabeth M. C. Fisher
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Victor L. J. Tybulewicz
- Division of Immune Cell Biology, MRC National Institute for Medical Research, London NW7 1AA, United Kingdom
| | - Sebastian Brandner
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - John Collinge
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| | - Sarah E. Lloyd
- Medical Research Council (MRC) Prion Unit and
- Department of Neurodegenerative Disease, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom; and
| |
Collapse
|
38
|
Mead S, Uphill J, Beck J, Poulter M, Campbell T, Lowe J, Adamson G, Hummerich H, Klopp N, Rückert IM, Wichmann HE, Azazi D, Plagnol V, Pako WH, Whitfield J, Alpers MP, Whittaker J, Balding DJ, Zerr I, Kretzschmar H, Collinge J. Genome-wide association study in multiple human prion diseases suggests genetic risk factors additional to PRNP. Hum Mol Genet 2012; 21:1897-906. [PMID: 22210626 PMCID: PMC3313791 DOI: 10.1093/hmg/ddr607] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 12/04/2011] [Accepted: 12/16/2011] [Indexed: 11/14/2022] Open
Abstract
Prion diseases are fatal neurodegenerative diseases of humans and animals caused by the misfolding and aggregation of prion protein (PrP). Mammalian prion diseases are under strong genetic control but few risk factors are known aside from the PrP gene locus (PRNP). No genome-wide association study (GWAS) has been done aside from a small sample of variant Creutzfeldt-Jakob disease (CJD). We conducted GWAS of sporadic CJD (sCJD), variant CJD (vCJD), iatrogenic CJD, inherited prion disease, kuru and resistance to kuru despite attendance at mortuary feasts. After quality control, we analysed 2000 samples and 6015 control individuals (provided by the Wellcome Trust Case Control Consortium and KORA-gen) for 491032-511862 SNPs in the European study. Association studies were done in each geographical and aetiological group followed by several combined analyses. The PRNP locus was highly associated with risk in all geographical and aetiological groups. This association was driven by the known coding variation at rs1799990 (PRNP codon 129). No non-PRNP loci achieved genome-wide significance in the meta-analysis of all human prion disease. SNPs at the ZBTB38-RASA2 locus were associated with CJD in the UK (rs295301, P = 3.13 × 10(-8); OR, 0.70) but these SNPs showed no replication evidence of association in German sCJD or in Papua New Guinea-based tests. A SNP in the CHN2 gene was associated with vCJD [P = 1.5 × 10(-7); odds ratio (OR), 2.36], but not in UK sCJD (P = 0.049; OR, 1.24), in German sCJD or in PNG groups. In the overall meta-analysis of CJD, 14 SNPs were associated (P < 10(-5); two at PRNP, three at ZBTB38-RASA2, nine at nine other independent non-PRNP loci), more than would be expected by chance. None of the loci recently identified as genome-wide significant in studies of other neurodegenerative diseases showed any clear evidence of association in prion diseases. Concerning common genetic variation, it is likely that the PRNP locus contains the only strong risk factors that act universally across human prion diseases. Our data are most consistent with several other risk loci of modest overall effects which will require further genetic association studies to provide definitive evidence.
Collapse
Affiliation(s)
- Simon Mead
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - James Uphill
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - John Beck
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - Mark Poulter
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - Tracy Campbell
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - Jessica Lowe
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - Gary Adamson
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - Holger Hummerich
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| | - Norman Klopp
- KORA-gen, Helmholtz-Zentrum München, Institute for Epidemiology, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - Ina-Maria Rückert
- KORA-gen, Helmholtz-Zentrum München, Institute for Epidemiology, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - H-Erich Wichmann
- KORA-gen, Helmholtz-Zentrum München, Institute for Epidemiology, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - Dhoyazan Azazi
- Department of Statistics, Institute of Genetics, University College London, Darwin Building Gower Street, London WC1E 6BT, UK
| | - Vincent Plagnol
- Department of Statistics, Institute of Genetics, University College London, Darwin Building Gower Street, London WC1E 6BT, UK
| | - Wandagi H. Pako
- Papua New Guinea (PNG) Institute of Medical Research, Goroka, EHP, Papua New Guinea
| | - Jerome Whitfield
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
- Centre for International Health, Curtin University, Perth, Australia
| | - Michael P. Alpers
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
- Papua New Guinea (PNG) Institute of Medical Research, Goroka, EHP, Papua New Guinea
- Centre for International Health, Curtin University, Perth, Australia
| | - John Whittaker
- London School of Hygiene and Tropical Medicine, LondonWC1E 7HT, UK
| | - David J. Balding
- Department of Statistics, Institute of Genetics, University College London, Darwin Building Gower Street, London WC1E 6BT, UK
| | - Inga Zerr
- Department of Neurology, Georg-August University Göttingen, Göttingen, Germany and
| | - Hans Kretzschmar
- Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Feodor-Lynen-Str. 23, D-81377 Munich, Germany
| | - John Collinge
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, LondonWC1N 3BG, UK
| |
Collapse
|
39
|
Akhtar S, Wenborn A, Brandner S, Collinge J, Lloyd SE. Sex effects in mouse prion disease incubation time. PLoS One 2011; 6:e28741. [PMID: 22174884 PMCID: PMC3236759 DOI: 10.1371/journal.pone.0028741] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 11/14/2011] [Indexed: 11/18/2022] Open
Abstract
Prion disease incubation time in mice is determined by many factors including PrP expression level, Prnp alleles, genetic background, prion strain and route of inoculation. Sex differences have been described in age of onset for vCJD and in disease duration for both vCJD and sporadic CJD and have also been shown in experimental models. The sex effects reported for mouse incubation times are often contradictory and detail only one strain of mice or prions, resulting in broad generalisations and a confusing picture. To clarify the effect of sex on prion disease incubation time in mice we have compared male and female transmission data from twelve different inbred lines of mice inoculated with at least two prion strains, representing both mouse-adapted scrapie and BSE. Our data show that sex can have a highly significant difference on incubation time. However, this is limited to particular mouse and prion strain combinations. No sex differences were seen in endogenous PrPC levels nor in the neuropathological markers of prion disease: PrPSc distribution, spongiosis, neuronal loss and gliosis. These data suggest that when comparing incubation times between experimental groups, such as testing the effects of modifier genes or therapeutics, single sex groups should be used.
Collapse
Affiliation(s)
- Shaheen Akhtar
- Medical Research Council Prion Unit and Department of Neurodegenerative Disease, University College London Institute of Neurology, London, United Kingdom
| | - Adam Wenborn
- Medical Research Council Prion Unit and Department of Neurodegenerative Disease, University College London Institute of Neurology, London, United Kingdom
| | - Sebastian Brandner
- Medical Research Council Prion Unit and Department of Neurodegenerative Disease, University College London Institute of Neurology, London, United Kingdom
| | - John Collinge
- Medical Research Council Prion Unit and Department of Neurodegenerative Disease, University College London Institute of Neurology, London, United Kingdom
| | - Sarah E. Lloyd
- Medical Research Council Prion Unit and Department of Neurodegenerative Disease, University College London Institute of Neurology, London, United Kingdom
- * E-mail:
| |
Collapse
|
40
|
Misfolded PrP impairs the UPS by interaction with the 20S proteasome and inhibition of substrate entry. EMBO J 2011; 30:3065-77. [PMID: 21743439 DOI: 10.1038/emboj.2011.224] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Accepted: 06/16/2011] [Indexed: 01/07/2023] Open
Abstract
Prion diseases are associated with the conversion of cellular prion protein (PrP(C)) to toxic β-sheet isoforms (PrP(Sc)), which are reported to inhibit the ubiquitin-proteasome system (UPS). Accordingly, UPS substrates accumulate in prion-infected mouse brains, suggesting impairment of the 26S proteasome. A direct interaction between its 20S core particle and PrP isoforms was demonstrated by immunoprecipitation. β-PrP aggregates associated with the 20S particle, but did not impede binding of the PA26 complex, suggesting that the aggregates do not bind to its ends. Aggregated β-PrP reduced the 20S proteasome's basal peptidase activity, and the enhanced activity induced by C-terminal peptides from the 19S ATPases or by the 19S regulator itself, including when stimulated by polyubiquitin conjugates. However, the 20S proteasome was not inhibited when the gate in the α-ring was open due to a truncation mutation or by association with PA26/PA28. These PrP aggregates inhibit by stabilising the closed conformation of the substrate entry channel. A similar inhibition of substrate entry into the proteasome may occur in other neurodegenerative diseases where misfolded β-sheet-rich proteins accumulate.
Collapse
|
41
|
A polymorphism in the YWHAH gene encoding 14-3-3 eta that is not associated with sporadic Creutzfeldt-Jakob disease (CJD). Mol Biol Rep 2011; 39:3619-25. [PMID: 21739144 DOI: 10.1007/s11033-011-1136-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 06/24/2011] [Indexed: 02/06/2023]
Abstract
14-3-3 proteins are abundantly expressed in the brain, particularly neuronal tissue and are thought to serve multiple biological functions involved in neuronal development and cell growth and death. Recent studies have shown associations of 14-3-3 genes with neurodegenerative disorders based on their chromosomal linkage to these diseases and to regulatory functions for the nervous system. Although the role of 14-3-3 proteins in the pathogenesis of prion diseases remains unknown, the detection of altered levels of isoforms of the 14-3-3 protein in the cerebrospinal fluid is considered a biomarker for diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD). To identify other susceptibility genes for prion disease, we examined nucleotide variations in YWHAH, a gene encoding 14-3-3 eta. This case-control study included 182 sCJD patients and 206 healthy Koreans. Polymerase chain reaction was used to amplify open reading frame and some 3'-untranslated region (UTR) in exon 2, and direct sequencing was carried out. One polymorphism, 753 G/A, was detected in the 3'-UTR of exon 2 on the YWHAH. The genotype distribution and allele frequencies of the YWHAH 753 G/A polymorphism were not significantly different between controls and sCJD patients. This finding indicates that YWHAH 753 G/A polymorphism is unlikely to be linked to genetic susceptibility or have a modifying effect in sCJD. On analysis stratified by the prion protein gene 129 or 219 genotype, no significant relation was found in genotype and allele frequencies of the YWHAH 753G/A. This is the first genetic association study of YWHAH with sCJD populations.
Collapse
|
42
|
Abstract
Over the last decade remarkable advances in genotyping and sequencing technology have resulted in hundreds of novel gene associations with disease. These have typically involved high frequency alleles in common diseases and with the advent of next generation sequencing, disease causing recessive mutations in rare inherited syndromes. Here we discuss the impact of these advances and other gene discovery methods in the prion diseases. Several quantitative trait loci in mouse have been mapped and their human counterparts analysed (HECTD2, CPNE8); other candidate genes regions have been chosen for functional reasons (SPRN, CTSD). Human genome wide association has been done in variant Creutzfeldt-Jakob disease (CJD) and are ongoing in larger collections of sporadic CJD with findings around, but not clearly beyond, the levels of statistical significance required in these studies (THRB-RARB, STMN2). Future work will include closer integration of animal and human genetic studies, larger and combined genome wide association, analysis of structural genetic variantion and next generation sequencing studies involving the entire coding exome or genome.
Collapse
Affiliation(s)
- Ana Lukic
- National Prion Clinic, UCLH NHS Trust, London, UK
| | | |
Collapse
|
43
|
Wadsworth JDF, Asante EA, Collinge J. Review: contribution of transgenic models to understanding human prion disease. Neuropathol Appl Neurobiol 2011; 36:576-97. [PMID: 20880036 PMCID: PMC3017745 DOI: 10.1111/j.1365-2990.2010.01129.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Transgenic mice expressing human prion protein in the absence of endogenous mouse prion protein faithfully replicate human prions. These models reproduce all of the key features of human disease, including long clinically silent incubation periods prior to fatal neurodegeneration with neuropathological phenotypes that mirror human prion strain diversity. Critical contributions to our understanding of human prion disease pathogenesis and aetiology have only been possible through the use of transgenic mice. These models have provided the basis for the conformational selection model of prion transmission barriers and have causally linked bovine spongiform encephalopathy with variant Creutzfeldt-Jakob disease. In the future these models will be essential for evaluating newly identified potentially zoonotic prion strains, for validating effective methods of prion decontamination and for developing effective therapeutic treatments for human prion disease.
Collapse
Affiliation(s)
- J D F Wadsworth
- MRC Prion Unit and Department of Neurodegenerative Disease, Institute of Neurology, University College London, National Hospital for Neurology and Neurosurgery, London, UK.
| | | | | |
Collapse
|
44
|
Wadsworth JDF, Collinge J. Molecular pathology of human prion disease. Acta Neuropathol 2011; 121:69-77. [PMID: 20694796 PMCID: PMC3015177 DOI: 10.1007/s00401-010-0735-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 07/29/2010] [Accepted: 07/30/2010] [Indexed: 11/28/2022]
Abstract
Human prion diseases are associated with a range of clinical presentations and are classified by both clinicopathological syndrome and aetiology with sub-classification according to molecular criteria. Considerable experimental evidence suggests that phenotypic diversity in human prion disease relates in significant part to the existence of distinct human prion strains encoded by abnormal PrP isoforms with differing physicochemical properties. To date, however, the conformational repertoire of pathological isoforms of wild-type human PrP and the various forms of mutant human PrP has not been fully defined. Efforts to produce a unified international classification of human prion disease are still ongoing. The ability of genetic background to influence prion strain selection together with knowledge of numerous other factors that may influence clinical and neuropathological presentation strongly emphasises the requirement to identify distinct human prion strains in appropriate transgenic models, where host genetic variability and other modifiers of phenotype are removed. Defining how many human prion strains exist allied with transgenic modelling of potentially zoonotic prion strains will inform on how many human infections may have an animal origin. Understanding these relationships will have direct translation to protecting public health.
Collapse
Affiliation(s)
- Jonathan D. F. Wadsworth
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG UK
| | - John Collinge
- MRC Prion Unit, Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG UK
| |
Collapse
|
45
|
Westaway D, Daude N, Wohlgemuth S, Harrison P. The PrP-Like Proteins Shadoo and Doppel. Top Curr Chem (Cham) 2011; 305:225-56. [DOI: 10.1007/128_2011_190] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
|
46
|
Abstract
Prion diseases or transmissible spongiform encephalopathies (TSEs) are neurodegenerative disorders of humans and animals for which there are no effective treatments or cure. They include Creutzfeldt-Jakob disease (CJD) in humans and sheep scrapie, bovine spongiform encephalopathy (BSE) and chronic wasting disease (CWD) in cervids. The prion protein (PrP) is central to the disease process. An abnormal form of PrP is generally considered to be the sole or principal component of the infectious agent and a multimeric isomer (PrP(Sc)) is deposited in affected brains. Inherited prion diseases are caused by over 30 mutations in the prion protein gene (PRNP) and common polymorphisms can have a considerable affect on susceptibility and phenotype. Susceptibility and incubation time are also partly determined by other (non-PRNP) genetic modifiers. Understanding how these other genes modify prion diseases may lead to insights into biological mechanisms. Several approaches including human genome wide association studies (GWAS), mouse mapping and differential expression studies are now revealing some of these genes which include RARB (retinoic acid receptor beta), the E3 ubiquitin ligase HECTD2 and SPRN (Shadoo, shadow of prion protein gene).
Collapse
Affiliation(s)
- Sarah Lloyd
- MRC Prion Unit and Department of Neurodegenerative Diseases, UCL Institute of Neurology, London, WC1N 3BG, UK
| | | | | |
Collapse
|
47
|
Wadsworth JDF, Dalmau-Mena I, Joiner S, Linehan JM, O'Malley C, Powell C, Brandner S, Asante EA, Ironside JW, Hilton DA, Collinge J. Effect of fixation on brain and lymphoreticular vCJD prions and bioassay of key positive specimens from a retrospective vCJD prevalence study. J Pathol 2010; 223:511-8. [PMID: 21294124 DOI: 10.1002/path.2821] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 10/21/2010] [Accepted: 11/06/2010] [Indexed: 11/11/2022]
Abstract
Anonymous screening of lymphoreticular tissues removed during routine surgery has been applied to estimate the UK population prevalence of asymptomatic vCJD prion infection. The retrospective study of Hilton et al (J Pathol 2004; 203: 733-739) found accumulation of abnormal prion protein in three formalin-fixed appendix specimens. This led to an estimated UK prevalence of vCJD infection of ∼1 in 4000, which remains the key evidence supporting current risk reduction measures to reduce iatrogenic transmission of vCJD prions in the UK. Confirmatory testing of these positives has been hampered by the inability to perform immunoblotting of formalin-fixed tissue. Animal transmission studies offer the potential for 'gold standard' confirmatory testing but are limited by both transmission barrier effects and known effects of fixation on scrapie prion titre in experimental models. Here we report the effects of fixation on brain and lymphoreticular human vCJD prions and comparative bioassay of two of the three prevalence study formalin-fixed, paraffin-embedded (FFPE) appendix specimens using transgenic mice expressing human prion protein (PrP). While transgenic mice expressing human PrP 129M readily reported vCJD prion infection after inoculation with frozen vCJD brain or appendix, and also FFPE vCJD brain, no infectivity was detected in FFPE vCJD spleen. No prion transmission was observed from either of the FFPE appendix specimens. The absence of detectable infectivity in fixed, known positive vCJD lymphoreticular tissue precludes interpreting negative transmissions from vCJD prevalence study appendix specimens. In this context, the Hilton et al study should continue to inform risk assessment pending the outcome of larger-scale studies on discarded surgical tissues and autopsy samples.
Collapse
Affiliation(s)
- Jonathan D F Wadsworth
- MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Grizenkova J, Akhtar S, Collinge J, Lloyd SE. The retinoic acid receptor beta (Rarb) region of Mmu14 is associated with prion disease incubation time in mouse. PLoS One 2010; 5:e15019. [PMID: 21151910 PMCID: PMC2997791 DOI: 10.1371/journal.pone.0015019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 10/10/2010] [Indexed: 11/18/2022] Open
Abstract
In neurodegenerative conditions such as Alzheimer's and prion disease it has been shown that host genetic background can have a significant effect on susceptibility. Indeed, human genome-wide association studies (GWAS) have implicated several candidate genes. Understanding such genetic susceptibility is relevant to risks of developing variant CJD (vCJD) in populations exposed to bovine spongiform encephalopathy (BSE) and understanding mechanisms of neurodegeneration. In mice, aspects of prion disease susceptibility can be modelled by examining the incubation period following experimental inoculation. Quantitative trait linkage studies have already identified multiple candidate genes; however, it is also possible to take an individual candidate gene approach. Rarb and Stmn2 were selected as candidates based on the known association with vCJD. Because of the increasing overlap described between prion and Alzheimer's diseases we also chose Clu, Picalm and Cr1, which were identified as part of Alzheimer's disease GWAS. Clusterin (Clu) was considered to be of particular interest as it has already been implicated in prion disease. Approximately 1,000 heterogeneous stock (HS) mice were inoculated intra-cerebrally with Chandler/RML prions and incubation times were recorded. Candidate genes were evaluated by sequencing the whole transcript including exon-intron boundaries and potential promoters in the parental lines of the HS mice. Representative SNPs were genotyped in the HS mice. No SNPs were identified in Cr1 and no statistical association with incubation time was seen for Clu (P = 0.96) and Picalm (P = 0.91). Significant associations were seen for both Stmn2 (P = 0.04) and Rarb (P = 0.0005), however, this was only highly significant for Rarb. This data provides significant further support for a role for the Rarb region of Mmu14 and Stmn2 in prion disease.
Collapse
Affiliation(s)
- Julia Grizenkova
- MRC Prion Unit and Department of Neurodegenerative Diseases, UCL Institute of Neurology, University College, London, United Kingdom
| | - Shaheen Akhtar
- MRC Prion Unit and Department of Neurodegenerative Diseases, UCL Institute of Neurology, University College, London, United Kingdom
| | - John Collinge
- MRC Prion Unit and Department of Neurodegenerative Diseases, UCL Institute of Neurology, University College, London, United Kingdom
| | - Sarah E. Lloyd
- MRC Prion Unit and Department of Neurodegenerative Diseases, UCL Institute of Neurology, University College, London, United Kingdom
- * E-mail:
| |
Collapse
|
49
|
Tang Y, Xiang W, Terry L, Kretzschmar HA, Windl O. Transcriptional analysis implicates endoplasmic reticulum stress in bovine spongiform encephalopathy. PLoS One 2010; 5:e14207. [PMID: 21151970 PMCID: PMC2997050 DOI: 10.1371/journal.pone.0014207] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 11/01/2010] [Indexed: 11/18/2022] Open
Abstract
Bovine spongiform encephalopathy (BSE) is a fatal, transmissible, neurodegenerative disease of cattle. To date, the disease process is still poorly understood. In this study, brain tissue samples from animals naturally infected with BSE were analysed to identify differentially regulated genes using Affymetrix GeneChip Bovine Genome Arrays. A total of 230 genes were shown to be differentially regulated and many of these genes encode proteins involved in immune response, apoptosis, cell adhesion, stress response and transcription. Seventeen genes are associated with the endoplasmic reticulum (ER) and 10 of these 17 genes are involved in stress related responses including ER chaperones, Grp94 and Grp170. Western blotting analysis showed that another ER chaperone, Grp78, was up-regulated in BSE. Up-regulation of these three chaperones strongly suggests the presence of ER stress and the activation of the unfolded protein response (UPR) in BSE. The occurrence of ER stress was also supported by changes in gene expression for cytosolic proteins, such as the chaperone pair of Hsp70 and DnaJ. Many genes associated with the ubiquitin-proteasome pathway and the autophagy-lysosome system were differentially regulated, indicating that both pathways might be activated in response to ER stress. A model is presented to explain the mechanisms of prion neurotoxicity using these ER stress related responses. Clustering analysis showed that the differently regulated genes found from the naturally infected BSE cases could be used to predict the infectious status of the samples experimentally infected with BSE from the previous study and vice versa. Proof-of-principle gene expression biomarkers were found to represent BSE using 10 genes with 94% sensitivity and 87% specificity.
Collapse
Affiliation(s)
- Yue Tang
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, Surrey, United Kingdom
- * E-mail: (YT); (OW)
| | - Wei Xiang
- Institute of Biochemistry, Emil-Fischer-Center, University Erlangen-Nuernberg, Erlangen, Germany
| | - Linda Terry
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, Surrey, United Kingdom
| | - Hans A. Kretzschmar
- Institute of Neuropathology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Otto Windl
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, Surrey, United Kingdom
- * E-mail: (YT); (OW)
| |
Collapse
|
50
|
Iyegbe CO, Abiola OO, Towlson C, Powell JF, Whatley SA. Evidence for varied aetiologies regulating the transmission of prion disease: implications for understanding the heritable basis of prion incubation times. PLoS One 2010; 5:e14186. [PMID: 21152031 PMCID: PMC2996284 DOI: 10.1371/journal.pone.0014186] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 08/12/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Transmissible Spongiform Encephalopathies (TSEs) are a group of progressive fatal neurodegenerative disorders, triggered by abnormal folding of the endogenous prion protein molecule. The encoding gene is a major biological factor influencing the length of the asymptomatic period after infection. It remains unclear the extent to which the variation between quantitative trait loci (QTLs) reported in mouse models is due to methodological differences between approaches or genuine differences between traits. With this in mind, our approach to identifying genetic factors has sought to extend the linkage mapping approach traditionally applied, to a series of additional traits, while minimising methodological variability between them. Our approach allows estimations of heritability to be derived, as well as predictions to be made about possible existence of genetic overlap between the various traits. METHODOLOGY/PRINCIPAL FINDINGS Our data indicate a surprising degree of heritability (up to 60%). Correlations between traits are also identified. A series of QTLs on chromosomes 1, 2, 3, 4, 6, 11 and 18 accompany our heritability estimates. However, only a locus on chromosome 11 has a general effect across all 4 models explored. CONCLUSIONS/SIGNIFICANCE We have achieved some success in detecting novel and pre-existing QTLs associated with incubation time. However, aside from the general effects described, the model-specific nature of the broader host genetic architecture has also been brought into clearer focus. This suggests that genetic overlap can only partially account for the general heritability of incubation time when factors, such as the nature of the TSE agent and the route of administration are considered. This point is highly relevant to vCJD (a potential threat to public health) where the route of primary importance is oral, while the QTLs being sought derive exclusively from studies of the ic route. Our results highlight the limitations of a single-model approach to QTL-mapping of TSEs.
Collapse
Affiliation(s)
- Conrad O Iyegbe
- Psychosis Centre, Institute of Psychiatry, King's College London, London, United Kingdom.
| | | | | | | | | |
Collapse
|