1
|
Celauro L, Zattoni M, Legname G. Prion receptors, prion internalization, intra- and inter-cellular transport. Prog Mol Biol Transl Sci 2023; 196:15-41. [PMID: 36813357 DOI: 10.1016/bs.pmbts.2022.06.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Luigi Celauro
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Marco Zattoni
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy.
| |
Collapse
|
2
|
Avar M, Heinzer D, Thackray AM, Liu Y, Hruska‐Plochan M, Sellitto S, Schaper E, Pease DP, Yin J, Lakkaraju AKK, Emmenegger M, Losa M, Chincisan A, Hornemann S, Polymenidou M, Bujdoso R, Aguzzi A. An arrayed genome-wide perturbation screen identifies the ribonucleoprotein Hnrnpk as rate-limiting for prion propagation. EMBO J 2022; 41:e112338. [PMID: 36254605 PMCID: PMC9713719 DOI: 10.15252/embj.2022112338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 09/17/2022] [Accepted: 09/22/2022] [Indexed: 01/15/2023] Open
Abstract
A defining characteristic of mammalian prions is their capacity for self-sustained propagation. Theoretical considerations and experimental evidence suggest that prion propagation is modulated by cell-autonomous and non-autonomous modifiers. Using a novel quantitative phospholipase protection assay (QUIPPER) for high-throughput prion measurements, we performed an arrayed genome-wide RNA interference (RNAi) screen aimed at detecting cellular host-factors that can modify prion propagation. We exposed prion-infected cells in high-density microplates to 35,364 ternary pools of 52,746 siRNAs targeting 17,582 genes representing the majority of the mouse protein-coding transcriptome. We identified 1,191 modulators of prion propagation. While 1,151 modified the expression of both the pathological prion protein, PrPSc , and its cellular counterpart, PrPC , 40 genes selectively affected PrPSc . Of the latter 40 genes, 20 augmented prion production when suppressed. A prominent limiter of prion propagation was the heterogeneous nuclear ribonucleoprotein Hnrnpk. Psammaplysene A (PSA), which binds Hnrnpk, reduced prion levels in cultured cells and protected them from cytotoxicity. PSA also reduced prion levels in infected cerebellar organotypic slices and alleviated locomotor deficits in prion-infected Drosophila melanogaster expressing ovine PrPC . Hence, genome-wide QUIPPER-based perturbations can discover actionable cellular pathways involved in prion propagation. Further, the unexpected identification of a prion-controlling ribonucleoprotein suggests a role for RNA in the generation of infectious prions.
Collapse
Affiliation(s)
- Merve Avar
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Daniel Heinzer
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Alana M Thackray
- Department of Veterinary MedicineUniversity of CambridgeCambridgeUK
| | - Yingjun Liu
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | | | - Stefano Sellitto
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Elke Schaper
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Daniel P Pease
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Jiang‐An Yin
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | | | - Marc Emmenegger
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Marco Losa
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Andra Chincisan
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | - Simone Hornemann
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| | | | - Raymond Bujdoso
- Department of Veterinary MedicineUniversity of CambridgeCambridgeUK
| | - Adriano Aguzzi
- Institute of NeuropathologyUniversity of ZurichZurichSwitzerland
| |
Collapse
|
3
|
Frontzek K, Bardelli M, Senatore A, Henzi A, Reimann RR, Bedir S, Marino M, Hussain R, Jurt S, Meisl G, Pedotti M, Mazzola F, Siligardi G, Zerbe O, Losa M, Knowles T, Lakkaraju A, Zhu C, Schwarz P, Hornemann S, Holt MG, Simonelli L, Varani L, Aguzzi A. A conformational switch controlling the toxicity of the prion protein. Nat Struct Mol Biol 2022; 29:831-40. [PMID: 35948768 DOI: 10.1038/s41594-022-00814-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 07/06/2022] [Indexed: 11/08/2022]
Abstract
Prion infections cause conformational changes of the cellular prion protein (PrPC) and lead to progressive neurological impairment. Here we show that toxic, prion-mimetic ligands induce an intramolecular R208-H140 hydrogen bond ('H-latch'), altering the flexibility of the α2-α3 and β2-α2 loops of PrPC. Expression of a PrP2Cys mutant mimicking the H-latch was constitutively toxic, whereas a PrPR207A mutant unable to form the H-latch conferred resistance to prion infection. High-affinity ligands that prevented H-latch induction repressed prion-related neurodegeneration in organotypic cerebellar cultures. We then selected phage-displayed ligands binding wild-type PrPC, but not PrP2Cys. These binders depopulated H-latched conformers and conferred protection against prion toxicity. Finally, brain-specific expression of an antibody rationally designed to prevent H-latch formation prolonged the life of prion-infected mice despite unhampered prion propagation, confirming that the H-latch is an important reporter of prion neurotoxicity.
Collapse
|
4
|
Mehrabian M, Wang X, Eid S, Yan BQ, Grinberg M, Siegner M, Sackmann C, Sulman M, Zhao W, Williams D, Schmitt-Ulms G. Cardiac glycoside-mediated turnover of Na, K-ATPases as a rational approach to reducing cell surface levels of the cellular prion protein. PLoS One 2022; 17:e0270915. [PMID: 35776750 PMCID: PMC9249225 DOI: 10.1371/journal.pone.0270915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 06/17/2022] [Indexed: 01/16/2023] Open
Abstract
It is widely anticipated that a reduction of brain levels of the cellular prion protein (PrPC) can prolong survival in a group of neurodegenerative diseases known as prion diseases. To date, efforts to decrease steady-state PrPC levels by targeting this protein directly with small molecule drug-like compounds have largely been unsuccessful. Recently, we reported Na,K-ATPases to reside in immediate proximity to PrPC in the brain, unlocking an opportunity for an indirect PrPC targeting approach that capitalizes on the availability of potent cardiac glycosides (CGs). Here, we report that exposure of human co-cultures of neurons and astrocytes to non-toxic nanomolar levels of CGs causes profound reductions in PrPC levels. The mechanism of action underpinning this outcome relies primarily on a subset of CGs engaging the ATP1A1 isoform, one of three α subunits of Na,K-ATPases expressed in brain cells. Upon CG docking to ATP1A1, the ligand receptor complex, and PrPC along with it, is internalized by the cell. Subsequently, PrPC is channeled to the lysosomal compartment where it is digested in a manner that can be rescued by silencing the cysteine protease cathepsin B. These data signify that the repurposing of CGs may be beneficial for the treatment of prion disorders.
Collapse
Affiliation(s)
- Mohadeseh Mehrabian
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Xinzhu Wang
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Shehab Eid
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Bei Qi Yan
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Mark Grinberg
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Murdock Siegner
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Christopher Sackmann
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Muhammad Sulman
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Wenda Zhao
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Declan Williams
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Gerold Schmitt-Ulms
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
| |
Collapse
|
5
|
Heinzer D, Avar M, Pease DP, Dhingra A, Yin JA, Schaper E, Doğançay B, Emmenegger M, Spinelli A, Maggi K, Chincisan A, Mead S, Hornemann S, Heutink P, Aguzzi A. Novel regulators of PrPC biosynthesis revealed by genome-wide RNA interference. PLoS Pathog 2021; 17:e1010013. [PMID: 34705895 DOI: 10.1371/journal.ppat.1010013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/08/2021] [Accepted: 10/07/2021] [Indexed: 11/29/2022] Open
Abstract
The cellular prion protein PrPC is necessary for prion replication, and its reduction greatly increases life expectancy in animal models of prion infection. Hence the factors controlling the levels of PrPC may represent therapeutic targets against human prion diseases. Here we performed an arrayed whole-transcriptome RNA interference screen to identify modulators of PrPC expression. We cultured human U251-MG glioblastoma cells in the presence of 64’752 unique siRNAs targeting 21’584 annotated human genes, and measured PrPC using a one-pot fluorescence-resonance energy transfer immunoassay in 51’128 individual microplate wells. This screen yielded 743 candidate regulators of PrPC. When downregulated, 563 of these candidates reduced and 180 enhanced PrPC expression. Recursive candidate attrition through multiple secondary screens yielded 54 novel regulators of PrPC, 9 of which were confirmed by CRISPR interference as robust regulators of PrPC biosynthesis and degradation. The phenotypes of 6 of the 9 candidates were inverted in response to transcriptional activation using CRISPRa. The RNA-binding post-transcriptional repressor Pumilio-1 was identified as a potent limiter of PrPC expression through the degradation of PRNP mRNA. Because of its hypothesis-free design, this comprehensive genetic-perturbation screen delivers an unbiased landscape of the genes regulating PrPC levels in cells, most of which were unanticipated, and some of which may be amenable to pharmacological targeting in the context of antiprion therapies. The cellular prion protein (PrPC) acts as both, the substrate for prion formation and mediator of prion toxicity during the progression of all prion diseases. Suppressing the levels of PrPC is a viable therapeutic strategy as PRNP null animals are resistant to prion disease and the knockout of PRNP is not associated with any severe phenotypes. Motivated by the scarcity of knowledge regarding the molecular regulators of PrPC biosynthesis and degradation, which might serve as valuable targets to control its expression, here, we present a cell-based genome wide RNAi screen in arrayed format. The screening effort led to the identification of 54 regulators, nine of which were confirmed by an independent CRISPR-based method. Among the final nine targets, we identified PUM1 as a regulator of PRNP mRNA by acting on the 3’UTR promoting its degradation. The newly identified factors involved in the life cycle of PrPC provided by our study may also represent themselves as therapeutic targets for the intervention of prion diseases.
Collapse
|
6
|
Meisl G, Kurt T, Condado-Morales I, Bett C, Sorce S, Nuvolone M, Michaels TCT, Heinzer D, Avar M, Cohen SIA, Hornemann S, Aguzzi A, Dobson CM, Sigurdson CJ, Knowles TPJ. Scaling analysis reveals the mechanism and rates of prion replication in vivo. Nat Struct Mol Biol 2021; 28:365-372. [PMID: 33767451 PMCID: PMC8922999 DOI: 10.1038/s41594-021-00565-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 01/26/2021] [Indexed: 01/03/2023]
Abstract
Prions consist of pathological aggregates of cellular prion protein and have the ability to replicate, causing neurodegenerative diseases, a phenomenon mirrored in many other diseases connected to protein aggregation, including Alzheimer's and Parkinson's diseases. However, despite their key importance in disease, the individual processes governing this formation of pathogenic aggregates, as well as their rates, have remained challenging to elucidate in vivo. Here we bring together a mathematical framework with kinetics of the accumulation of prions in mice and microfluidic measurements of aggregate size to dissect the overall aggregation reaction into its constituent processes and quantify the reaction rates in mice. Taken together, the data show that multiplication of prions in vivo is slower than in in vitro experiments, but efficient when compared with other amyloid systems, and displays scaling behavior characteristic of aggregate fragmentation. These results provide a framework for the determination of the mechanisms of disease-associated aggregation processes within living organisms.
Collapse
Affiliation(s)
- Georg Meisl
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Timothy Kurt
- Department of Pathology, UC San Diego, San Diego, CA, USA
| | - Itzel Condado-Morales
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Cyrus Bett
- Department of Pathology, UC San Diego, San Diego, CA, USA
| | - Silvia Sorce
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Mario Nuvolone
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
- Amyloidosis Research and Treatment Center, Foundation IRCCS Policlinico San Matteo, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Thomas C T Michaels
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
- Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Daniel Heinzer
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Merve Avar
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Samuel I A Cohen
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
- Wren Therapeutics, Cambridge, UK
| | - Simone Hornemann
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Adriano Aguzzi
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Christopher M Dobson
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | | | - Tuomas P J Knowles
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK.
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
| |
Collapse
|
7
|
Alves RN, Iglesia RP, Prado MB, Melo Escobar MI, Boccacino JM, Fernandes CFL, Coelho BP, Fortes AC, Lopes MH. A New Take on Prion Protein Dynamics in Cellular Trafficking. Int J Mol Sci 2020; 21:E7763. [PMID: 33092231 DOI: 10.3390/ijms21207763] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 12/12/2022] Open
Abstract
The mobility of cellular prion protein (PrPC) in specific cell membrane domains and among distinct cell compartments dictates its molecular interactions and directs its cell function. PrPC works in concert with several partners to organize signaling platforms implicated in various cellular processes. The scaffold property of PrPC is able to gather a molecular repertoire to create heterogeneous membrane domains that favor endocytic events. Dynamic trafficking of PrPC through multiple pathways, in a well-orchestrated mechanism of intra and extracellular vesicular transport, defines its functional plasticity, and also assists the conversion and spreading of its infectious isoform associated with neurodegenerative diseases. In this review, we highlight how PrPC traffics across intra- and extracellular compartments and the consequences of this dynamic transport in governing cell functions and contributing to prion disease pathogenesis.
Collapse
|
8
|
Senatore A, Frontzek K, Emmenegger M, Chincisan A, Losa M, Reimann R, Horny G, Guo J, Fels S, Sorce S, Zhu C, George N, Ewert S, Pietzonka T, Hornemann S, Aguzzi A. Protective anti-prion antibodies in human immunoglobulin repertoires. EMBO Mol Med 2020; 12:e12739. [PMID: 32776637 PMCID: PMC7506995 DOI: 10.15252/emmm.202012739] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/10/2020] [Accepted: 07/10/2020] [Indexed: 01/09/2023] Open
Abstract
Prion immunotherapy may hold great potential, but antibodies against certain PrP epitopes can be neurotoxic. Here, we identified > 6,000 PrP-binding antibodies in a synthetic human Fab phage display library, 49 of which we characterized in detail. Antibodies directed against the flexible tail of PrP conferred neuroprotection against infectious prions. We then mined published repertoires of circulating B cells from healthy humans and found antibodies similar to the protective phage-derived antibodies. When expressed recombinantly, these antibodies exhibited anti-PrP reactivity. Furthermore, we surveyed 48,718 samples from 37,894 hospital patients for the presence of anti-PrP IgGs and found 21 high-titer individuals. The clinical files of these individuals did not reveal any enrichment of specific pathologies, suggesting that anti-PrP autoimmunity is innocuous. The existence of anti-prion antibodies in unbiased human immunological repertoires suggests that they might clear nascent prions early in life. Combined with the reported lack of such antibodies in carriers of disease-associated PRNP mutations, this suggests a link to the low incidence of spontaneous prion diseases in human populations.
Collapse
Affiliation(s)
- Assunta Senatore
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Karl Frontzek
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Marc Emmenegger
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Andra Chincisan
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Marco Losa
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Regina Reimann
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Geraldine Horny
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Jingjing Guo
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Sylvie Fels
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Silvia Sorce
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Caihong Zhu
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Nathalie George
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Stefan Ewert
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | | | - Simone Hornemann
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Adriano Aguzzi
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| |
Collapse
|
9
|
Jones E, Mead S. Genetic risk factors for Creutzfeldt-Jakob disease. Neurobiol Dis 2020; 142:104973. [PMID: 32565065 DOI: 10.1016/j.nbd.2020.104973] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/18/2020] [Accepted: 06/13/2020] [Indexed: 10/24/2022] Open
Abstract
Prion diseases are a group of fatal neurodegenerative disorders of mammals that share a central role for prion protein (PrP, gene PRNP) in their pathogenesis. Prions are infectious agents that account for the observed transmission of prion diseases between humans and animals in certain circumstances. The prion mechanism invokes a misfolded and multimeric assembly of PrP (a prion) that grows by templating of the normal protein and propagates by fission. Aside from the medical and public health notoriety of acquired prion diseases, the conditions have attracted interest as it has been realized that common neurodegenerative disorders share so-called prion-like mechanisms. In this article we will expand on recent evidence for new genetic loci that alter the risk of human prion disease. The most common human prion disease, sporadic Creutzfeldt-Jakob disease (sCJD), is characterized by the seemingly spontaneous appearance of prions in the brain. Genetic variation within PRNP is associated with all types of prion diseases, in particular, heterozygous genotypes at codons 129 and 219 have long been known to be strong protective factors against sCJD. A large number of rare mutations have been described in PRNP that cause autosomal dominant inherited prion diseases. Two loci recently identified by genome-wide association study increase sCJD risk, including variants in or near to STX6 and GAL3ST1. STX6 encodes syntaxin-6, a component of SNARE complexes with cellular roles that include the fusion of intracellular vesicles with target membranes. GAL3ST1 encodes cerebroside sulfotransferase, the only enzyme that sulfates sphingolipids to make sulfatides, a major lipid component of myelin. We discuss how these roles may modify the pathogenesis of prion diseases and their relevance for other neurodegenerative disorders.
Collapse
Affiliation(s)
- Emma Jones
- MRC Prion Unit at University College London (UCL), UCL Institute of Prion Diseases, 33 Cleveland Street, W1W 7FF, United Kingdom
| | - Simon Mead
- MRC Prion Unit at University College London (UCL), UCL Institute of Prion Diseases, 33 Cleveland Street, W1W 7FF, United Kingdom.
| |
Collapse
|
10
|
Pease D, Scheckel C, Schaper E, Eckhardt V, Emmenegger M, Xenarios I, Aguzzi A. Genome-wide identification of microRNAs regulating the human prion protein. Brain Pathol 2018; 29:232-244. [PMID: 30451334 DOI: 10.1111/bpa.12679] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 11/11/2018] [Indexed: 12/23/2022] Open
Abstract
The cellular prion protein (PrPC ) is best known for its misfolded disease-causing conformer, PrPSc . Because the availability of PrPC is often limiting for prion propagation, understanding its regulation may point to possible therapeutic targets. We sought to determine to what extent the human microRNAome is involved in modulating PrPC levels through direct or indirect pathways. We probed PrPC protein levels in cells subjected to a genome-wide library encompassing 2019 miRNA mimics using a robust time-resolved fluorescence-resonance screening assay. Screening was performed in three human neuroectodermal cell lines: U-251 MG, CHP-212 and SH-SY5Y. The three screens yielded 17 overlapping high-confidence miRNA mimic hits, 13 of which were found to regulate PrPC biosynthesis directly via binding to the PRNP 3'UTR, thereby inducing transcript degradation. The four remaining hits (miR-124-3p, 192-3p, 299-5p and 376b-3p) did not bind either the 3'UTR or CDS of PRNP, and were therefore deemed indirect regulators of PrPC . Our results show that multiple miRNAs regulate PrPC levels both directly and indirectly. These findings may have profound implications for prion disease pathogenesis and potentially also for their therapy. Furthermore, the possible role of PrPC as a mediator of Aβ toxicity suggests that its regulation by miRNAs may also impinge on Alzheimer's disease.
Collapse
Affiliation(s)
- Daniel Pease
- Institute of Neuropathology, University of Zürich, Zürich, Switzerland
| | - Claudia Scheckel
- Institute of Neuropathology, University of Zürich, Zürich, Switzerland
| | - Elke Schaper
- Institute of Neuropathology, University of Zürich, Zürich, Switzerland.,Center of Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Valeria Eckhardt
- Institute of Neuropathology, University of Zürich, Zürich, Switzerland
| | - Marc Emmenegger
- Institute of Neuropathology, University of Zürich, Zürich, Switzerland
| | - Ioannis Xenarios
- Center of Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Adriano Aguzzi
- Institute of Neuropathology, University of Zürich, Zürich, Switzerland
| |
Collapse
|
11
|
Bartoletti-Stella A, Corrado P, Mometto N, Baiardi S, Durrenberger PF, Arzberger T, Reynolds R, Kretzschmar H, Capellari S, Parchi P. Analysis of RNA Expression Profiles Identifies Dysregulated Vesicle Trafficking Pathways in Creutzfeldt-Jakob Disease. Mol Neurobiol 2018; 56:5009-5024. [PMID: 30446946 DOI: 10.1007/s12035-018-1421-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/01/2018] [Indexed: 12/21/2022]
Abstract
Functional genomics applied to the study of RNA expression profiles identified several abnormal molecular processes in experimental prion disease. However, only a few similar studies have been carried out to date in a naturally occurring human prion disease. To better characterize the transcriptional cascades associated with sporadic Creutzfeldt-Jakob disease (sCJD), the most common human prion disease, we investigated the global gene expression profile in samples from the frontal cortex of 10 patients with sCJD and 10 non-neurological controls by microarray analysis. The comparison identified 333 highly differentially expressed genes (hDEGs) in sCJD. Functional enrichment Gene Ontology analysis revealed that hDEGs were mainly associated with synaptic transmission, including GABA (q value = 0.049) and glutamate (q value = 0.005) signaling, and the immune/inflammatory response. Furthermore, the analysis of cellular components performed on hDEGs showed a compromised regulation of vesicle-mediated transport with mainly up-regulated genes related to the endosome (q value = 0.01), lysosome (q value = 0.04), and extracellular exosome (q value < 0.01). A targeted analysis of the retromer core component VPS35 (vacuolar protein sorting-associated protein 35) showed a down-regulation of gene expression (p value= 0.006) and reduced brain protein levels (p value= 0.002). Taken together, these results confirm and expand previous microarray expression profile data in sCJD. Most significantly, they also demonstrate the involvement of the endosomal-lysosomal system. Since the latter is a common pathogenic pathway linking together diseases, such as Alzheimer's and Parkinson's, it might be the focus of future studies aimed to identify new therapeutic targets in neurodegenerative diseases.
Collapse
Affiliation(s)
- Anna Bartoletti-Stella
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, 40139, Bologna, Italy
| | - Patrizia Corrado
- Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy
| | - Nicola Mometto
- Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy
| | - Simone Baiardi
- Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy
| | - Pascal F Durrenberger
- Centre for Inflammation and Tissue Repair, UCL Respiratory, University College London, Rayne Building, London, UK
| | - Thomas Arzberger
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University Munich, Munich, Germany.,Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich, Germany
| | | | - Hans Kretzschmar
- Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Sabina Capellari
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, 40139, Bologna, Italy. .,Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy.
| | - Piero Parchi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, 40139, Bologna, Italy. .,Department of Experimental, Diagnostic and Specialty Medicine, DIMES, University of Bologna, 40138, Bologna, Italy.
| |
Collapse
|
12
|
Keller A, Nuvolone M, Abakumova I, Chincisan A, Reimann R, Avar M, Heinzer D, Hornemann S, Wagner J, Kirschenbaum D, Voigt FF, Zhu C, Regli L, Helmchen F, Aguzzi A. Prion pathogenesis is unaltered in a mouse strain with a permeable blood-brain barrier. PLoS Pathog 2018; 14:e1007424. [PMID: 30496289 PMCID: PMC6264140 DOI: 10.1371/journal.ppat.1007424] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 10/19/2018] [Indexed: 01/01/2023] Open
Abstract
Transmissible spongiform encephalopathies (TSEs) are caused by the prion, which consists essentially of PrPSc, an aggregated, conformationally modified form of the cellular prion protein (PrPC). Although TSEs can be experimentally transmitted by intracerebral inoculation, most instances of infection in the field occur through extracerebral routes. The epidemics of kuru and variant Creutzfeldt-Jakob disease were caused by dietary exposure to prions, and parenteral administration of prion-contaminated hormones has caused hundreds of iatrogenic TSEs. In all these instances, the development of postexposure prophylaxis relies on understanding of how prions propagate from the site of entry to the brain. While much evidence points to lymphoreticular invasion followed by retrograde transfer through peripheral nerves, prions are present in the blood and may conceivably cross the blood-brain barrier directly. Here we have addressed the role of the blood-brain barrier (BBB) in prion disease propagation using Pdgfbret/ret mice which possess a highly permeable BBB. We found that Pdgfbret/ret mice have a similar prion disease incubation time as their littermate controls regardless of the route of prion transmission. These surprising results indicate that BBB permeability is irrelevant to the initiation of prion disease, even when prions are administered parenterally.
Collapse
Affiliation(s)
- Annika Keller
- Department of Neurosurgery, Clinical Neuroscience Centre, University Hospital Zürich, Zürich University, Zürich, Switzerland
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Mario Nuvolone
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
- Amyloidosis Research and Treatment Center, Foundation IRCCS Policlinico San Matteo, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Irina Abakumova
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Andra Chincisan
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Regina Reimann
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Merve Avar
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Daniel Heinzer
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Simone Hornemann
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Josephin Wagner
- Department of Neurosurgery, Clinical Neuroscience Centre, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Daniel Kirschenbaum
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Fabian F. Voigt
- Brain Research Institute, Zürich University, Zürich, Switzerland
- Neuroscience Center Zürich (ZNZ), University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Caihong Zhu
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Luca Regli
- Department of Neurosurgery, Clinical Neuroscience Centre, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Fritjof Helmchen
- Brain Research Institute, Zürich University, Zürich, Switzerland
- Neuroscience Center Zürich (ZNZ), University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| |
Collapse
|
13
|
Fehlinger A, Wolf H, Hossinger A, Duernberger Y, Pleschka C, Riemschoss K, Liu S, Bester R, Paulsen L, Priola SA, Groschup MH, Schätzl HM, Vorberg IM. Prion strains depend on different endocytic routes for productive infection. Sci Rep 2017; 7:6923. [PMID: 28761068 PMCID: PMC5537368 DOI: 10.1038/s41598-017-07260-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 06/27/2017] [Indexed: 01/08/2023] Open
Abstract
Prions are unconventional agents composed of misfolded prion protein that cause fatal neurodegenerative diseases in mammals. Prion strains induce specific neuropathological changes in selected brain areas. The mechanism of strain-specific cell tropism is unknown. We hypothesised that prion strains rely on different endocytic routes to invade and replicate within their target cells. Using prion permissive cells, we determined how impairment of endocytosis affects productive infection by prion strains 22L and RML. We demonstrate that early and late stages of prion infection are differentially sensitive to perturbation of clathrin- and caveolin-mediated endocytosis. Manipulation of canonical endocytic pathways only slightly influenced prion uptake. However, blocking the same routes had drastic strain-specific consequences on the establishment of infection. Our data argue that prion strains use different endocytic pathways for infection and suggest that cell type-dependent differences in prion uptake could contribute to host cell tropism.
Collapse
Affiliation(s)
- Andrea Fehlinger
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - Hanna Wolf
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - André Hossinger
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - Yvonne Duernberger
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - Catharina Pleschka
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - Katrin Riemschoss
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - Shu Liu
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - Romina Bester
- Institut für Virologie, Technische Universität München, Trogerstr. 30, 81675, München, Germany
| | - Lydia Paulsen
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany
| | - Suzette A Priola
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South 4th Street, Hamilton, MT, 59840, USA
| | - Martin H Groschup
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, 17493, Greifswald-Insel Riems, Germany
| | - Hermann M Schätzl
- Dept. of Comparative Biology & Experimental Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada
| | - Ina M Vorberg
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V., Sigmund-Freud-Strasse 27, 53127, Bonn, Germany. .,Department of Neurology, Rheinische Friedrich-Wilhelms-Universität, 53127, Bonn, Germany.
| |
Collapse
|