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Yeo JC, Tay FP, Bennion R, Loss O, Maignel J, Pons L, Foster K, Beard M, Bard F. Botulinum toxin intoxication requires retrograde transport and membrane translocation at the ER in RenVM neurons. eLife 2024; 12:RP92806. [PMID: 39196607 DOI: 10.7554/elife.92806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2024] Open
Abstract
Botulinum neurotoxin A (BoNT/A) is a highly potent proteolytic toxin specific for neurons with numerous clinical and cosmetic uses. After uptake at the synapse, the protein is proposed to translocate from synaptic vesicles to the cytosol through a self-formed channel. Surprisingly, we found that after intoxication proteolysis of a fluorescent reporter occurs in the neuron soma first and then centrifugally in neurites. To investigate the molecular mechanisms at play, we use a genome-wide siRNA screen in genetically engineered neurons and identify over three hundred genes. An organelle-specific split-mNG complementation indicates BoNT/A traffic from the synapse to the soma-localized Golgi in a retromer-dependent fashion. The toxin then moves to the ER and appears to require the Sec61 complex for retro-translocation to the cytosol. Our study identifies genes and trafficking processes hijacked by the toxin, revealing a new pathway mediating BoNT/A cellular toxicity.
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Affiliation(s)
- Jeremy C Yeo
- Institute of Molecular and Cell Biology, Singapore, Singapore
| | - Felicia P Tay
- Institute of Molecular and Cell Biology, Singapore, Singapore
| | - Rebecca Bennion
- Centre de Recherche en Cancérologie de Marseille, Aix Marseille Université, Inserm, CNRS, Institut Paoli-Calmettes, Equipe Leader Fondation ARC 2021, Marseille, France
| | - Omar Loss
- Ipsen Bioinnovation, London, United Kingdom
| | | | | | | | | | - Frederic Bard
- Institute of Molecular and Cell Biology, Singapore, Singapore
- Centre de Recherche en Cancérologie de Marseille, Aix Marseille Université, Inserm, CNRS, Institut Paoli-Calmettes, Equipe Leader Fondation ARC 2021, Marseille, France
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2
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Abstract
Vesicles mediate the trafficking of membranes/proteins in the endocytic and secretory pathways. These pathways are regulated by small GTPases of the Rab family. Rab proteins belong to the Ras superfamily of GTPases, which are significantly involved in various intracellular trafficking and signaling processes in the nervous system. Rab11 is known to play a key role especially in recycling many proteins, including receptors important for signal transduction and preservation of functional activities of nerve cells. Rab11 activity is controlled by GEFs (guanine exchange factors) and GAPs (GTPase activating proteins), which regulate its function through modulating GTP/GDP exchange and the intrinsic GTPase activity, respectively. Rab11 is involved in the transport of several growth factor molecules important for the development and repair of neurons. Overexpression of Rab11 has been shown to significantly enhance vesicle trafficking. On the other hand, a reduced expression of Rab11 was observed in several neurodegenerative diseases. Current evidence appears to support the notion that Rab11 and its cognate proteins may be potential targets for therapeutic intervention. In this review, we briefly discuss the function of Rab11 and its related interaction partners in intracellular pathways that may be involved in neurodegenerative processes.
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Affiliation(s)
| | - Jiri Novotny
- Jiri Novotny, Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic.
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3
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Saribas AS, Datta PK, Safak M. A comprehensive proteomics analysis of JC virus Agnoprotein-interacting proteins: Agnoprotein primarily targets the host proteins with coiled-coil motifs. Virology 2019; 540:104-118. [PMID: 31765920 DOI: 10.1016/j.virol.2019.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/13/2019] [Accepted: 10/16/2019] [Indexed: 11/29/2022]
Abstract
JC virus (JCV) Agnoprotein (Agno) plays critical roles in successful completion of the viral replication cycle. Understanding its regulatory roles requires a complete map of JCV-host protein interactions. Here, we report the first Agno interactome with host cellular targets utilizing "Two-Strep-Tag" affinity purification system coupled with mass spectroscopy (AP/MS). Proteomics data revealed that Agno primarily targets 501 cellular proteins, most of which contain "coiled-coil" motifs. Agno-host interactions occur in several cellular networks including those involved in protein synthesis and degradation; and cellular transport; and in organelles, including mitochondria, nucleus and ER-Golgi network. Among the Agno interactions, Rab11B, Importin and Crm-1 were first validated biochemically and further characterization was done for Crm-1, using a HIV-1 Rev-M10-like Agno mutant (L33D + E34L), revealing the critical roles of L33 and E34 residues in Crm-1 interaction. This comprehensive proteomics data provides new foundations to unravel the critical regulatory roles of Agno during the JCV life cycle.
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Affiliation(s)
- A Sami Saribas
- Department of Neuroscience, Laboratory of Molecular Neurovirology, Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA, 19140, USA
| | - Prasun K Datta
- Department of Neuroscience, Laboratory of Molecular Neurovirology, Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA, 19140, USA
| | - Mahmut Safak
- Department of Neuroscience, Laboratory of Molecular Neurovirology, Lewis Katz School of Medicine at Temple University, 3500 N. Broad Street, Philadelphia, PA, 19140, USA.
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Dimitriadi M, Derdowski A, Kalloo G, Maginnis MS, O'Hern P, Bliska B, Sorkaç A, Nguyen KCQ, Cook SJ, Poulogiannis G, Atwood WJ, Hall DH, Hart AC. Decreased function of survival motor neuron protein impairs endocytic pathways. Proc Natl Acad Sci U S A 2016; 113:E4377-86. [PMID: 27402754 PMCID: PMC4968725 DOI: 10.1073/pnas.1600015113] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Spinal muscular atrophy (SMA) is caused by depletion of the ubiquitously expressed survival motor neuron (SMN) protein, with 1 in 40 Caucasians being heterozygous for a disease allele. SMN is critical for the assembly of numerous ribonucleoprotein complexes, yet it is still unclear how reduced SMN levels affect motor neuron function. Here, we examined the impact of SMN depletion in Caenorhabditis elegans and found that decreased function of the SMN ortholog SMN-1 perturbed endocytic pathways at motor neuron synapses and in other tissues. Diminished SMN-1 levels caused defects in C. elegans neuromuscular function, and smn-1 genetic interactions were consistent with an endocytic defect. Changes were observed in synaptic endocytic proteins when SMN-1 levels decreased. At the ultrastructural level, defects were observed in endosomal compartments, including significantly fewer docked synaptic vesicles. Finally, endocytosis-dependent infection by JC polyomavirus (JCPyV) was reduced in human cells with decreased SMN levels. Collectively, these results demonstrate for the first time, to our knowledge, that SMN depletion causes defects in endosomal trafficking that impair synaptic function, even in the absence of motor neuron cell death.
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Affiliation(s)
- Maria Dimitriadi
- Department of Neuroscience, Brown University, Providence, RI 02912; Department of Biological and Environmental Sciences, University of Hertfordshire, Hatfield AL10 9AB, United Kingdom
| | - Aaron Derdowski
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912
| | - Geetika Kalloo
- Department of Neuroscience, Brown University, Providence, RI 02912
| | - Melissa S Maginnis
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912; Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME 04469
| | - Patrick O'Hern
- Department of Neuroscience, Brown University, Providence, RI 02912
| | - Bryn Bliska
- Department of Neuroscience, Brown University, Providence, RI 02912
| | - Altar Sorkaç
- Department of Neuroscience, Brown University, Providence, RI 02912
| | - Ken C Q Nguyen
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Steven J Cook
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - George Poulogiannis
- Chester Beatty Labs, The Institute of Cancer Research, London SW3 6JB, United Kingdom
| | - Walter J Atwood
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912
| | - David H Hall
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Anne C Hart
- Department of Neuroscience, Brown University, Providence, RI 02912;
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5
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Hu H, Bienefeld K, Wegener J, Zautke F, Hao Y, Feng M, Han B, Fang Y, Wubie AJ, Li J. Proteome Analysis of the Hemolymph, Mushroom Body, and Antenna Provides Novel Insight into Honeybee Resistance against Varroa Infestation. J Proteome Res 2016; 15:2841-54. [PMID: 27384112 DOI: 10.1021/acs.jproteome.6b00423] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Varroa destructor has been identified as a major culprit responsible for the losses of millions of honeybee colonies. Varroa sensitive hygiene (VSH) is a suite of behaviors from adult bees to suppress mite reproduction by uncapping and/or removing mite infested pupae from a sealed brood. Despite the efforts to elucidate the molecular underpinnings of VSH, they remain largely unknown. We investigated the proteome of mushroom bodies (MBs) and antennae of adult bees with and without VSH from a stock selected for VSH based on their response to artificially Varroa-infected brood cells by near-infrared camera observation. The pupal hemolymph proteome was also compared between the VSH-line and the line that was not selected for VSH. The identified 8609 proteins in the hemolymph, MBs, and antennae represent the most depth coverage of the honeybee proteome (>55%) to date. In the hemolymph, the VSH-line adapts a unique strategy to boost the social immunity and drive pupal organogenesis by enhancing energy metabolism and protein biosynthesis. In MBs, the up-regulated proteins implicated in neuronal sensitivity suggest their roles to promote the execution of VSH by activation of synaptic vesicles and calcium channel activities. In antennae, the highly expressed proteins associated with sensitivity of olfactory senses and signal transmissions signify their roles by inputting a strong signal to the MBs for initiating VSH. These observations illustrate that the enhanced social immunities and olfactory and neuronal sensitivity play key roles in the combat against Varroa infestation. The identified candidate markers may be useful for accelerating marker-associated selection for VSH to aid in resistance to a parasite responsible for decline in honeybee health.
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Affiliation(s)
- Han Hu
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science , Beijing 100093, China
| | - Kaspar Bienefeld
- Institute for Bee ResearchHohen Neuendorf , F.-Engels-Strasse 32, 16540 Hohen Neuendorf, Germany
| | - Jakob Wegener
- Institute for Bee ResearchHohen Neuendorf , F.-Engels-Strasse 32, 16540 Hohen Neuendorf, Germany
| | - Fred Zautke
- Institute for Bee ResearchHohen Neuendorf , F.-Engels-Strasse 32, 16540 Hohen Neuendorf, Germany
| | - Yue Hao
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science , Beijing 100093, China
| | - Mao Feng
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science , Beijing 100093, China
| | - Bin Han
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science , Beijing 100093, China
| | - Yu Fang
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science , Beijing 100093, China
| | - Abebe Jenberie Wubie
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science , Beijing 100093, China
| | - Jianke Li
- Institute of Apicultural Research/Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture, Chinese Academy of Agricultural Science , Beijing 100093, China
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6
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Fassio A, Fadda M, Benfenati F. Molecular Machines Determining the Fate of Endocytosed Synaptic Vesicles in Nerve Terminals. Front Synaptic Neurosci 2016; 8:10. [PMID: 27242505 PMCID: PMC4863888 DOI: 10.3389/fnsyn.2016.00010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/18/2016] [Indexed: 11/28/2022] Open
Abstract
The cycle of a synaptic vesicle (SV) within the nerve terminal is a step-by-step journey with the final goal of ensuring the proper synaptic strength under changing environmental conditions. The SV cycle is a precisely regulated membrane traffic event in cells and, because of this, a plethora of membrane-bound and cytosolic proteins are devoted to assist SVs in each step of the journey. The cycling fate of endocytosed SVs determines both the availability for subsequent rounds of release and the lifetime of SVs in the terminal and is therefore crucial for synaptic function and plasticity. Molecular players that determine the destiny of SVs in nerve terminals after a round of exo-endocytosis are largely unknown. Here we review the functional role in SV fate of phosphorylation/dephosphorylation of SV proteins and of small GTPases acting on membrane trafficking at the synapse, as they are emerging as key molecules in determining the recycling route of SVs within the nerve terminal. In particular, we focus on: (i) the cyclin-dependent kinase-5 (cdk5) and calcineurin (CN) control of the recycling pool of SVs; (ii) the role of small GTPases of the Rab and ADP-ribosylation factor (Arf) families in defining the route followed by SV in their nerve terminal cycle. These regulatory proteins together with their synaptic regulators and effectors, are molecular nanomachines mediating homeostatic responses in synaptic plasticity and potential targets of drugs modulating the efficiency of synaptic transmission.
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Affiliation(s)
- Anna Fassio
- Department of Experimental Medicine, University of GenoaGenoa, Italy; Center of Synaptic Neuroscience and Technology, Istituto Italiano di TecnologiaGenova, Italy
| | - Manuela Fadda
- Department of Experimental Medicine, University of Genoa Genoa, Italy
| | - Fabio Benfenati
- Department of Experimental Medicine, University of GenoaGenoa, Italy; Center of Synaptic Neuroscience and Technology, Istituto Italiano di TecnologiaGenova, Italy
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7
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Binotti B, Jahn R, Chua JJE. Functions of Rab Proteins at Presynaptic Sites. Cells 2016; 5:E7. [PMID: 26861397 PMCID: PMC4810092 DOI: 10.3390/cells5010007] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 02/03/2016] [Indexed: 01/24/2023] Open
Abstract
Presynaptic neurotransmitter release is dominated by the synaptic vesicle (SV) cycle and entails the biogenesis, fusion, recycling, reformation or turnover of synaptic vesicles-a process involving bulk movement of membrane and proteins. As key mediators of membrane trafficking, small GTPases from the Rab family of proteins play critical roles in this process by acting as molecular switches that dynamically interact with and regulate the functions of different sets of macromolecular complexes involved in each stage of the cycle. Importantly, mutations affecting Rabs, and their regulators or effectors have now been identified that are implicated in severe neurological and neurodevelopmental disorders. Here, we summarize the roles and functions of presynaptic Rabs and discuss their involvement in the regulation of presynaptic function.
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Affiliation(s)
- Beyenech Binotti
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Göttingen 37077, Germany
| | - Reinhard Jahn
- Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Göttingen 37077, Germany
| | - John Jia En Chua
- Interactomics and Intracellular Trafficking laboratory, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117456, Singapore.
- Neurobiology/Ageing Programme, National University of Singapore, Singapore 117456, Singapore.
- Research Group Protein trafficking in synaptic development and function, Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Göttingen 37077, Germany.
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8
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Affiliation(s)
- Carlo Breda
- Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Flaviano Giorgini
- Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Joern R. Steinert
- MRC Toxicology Unit, University of Leicester, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, UK
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9
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Breda C, Nugent ML, Estranero JG, Kyriacou CP, Outeiro TF, Steinert JR, Giorgini F. Rab11 modulates α-synuclein-mediated defects in synaptic transmission and behaviour. Hum Mol Genet 2015; 24:1077-91. [PMID: 25305083 PMCID: PMC4986550 DOI: 10.1093/hmg/ddu521] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 09/17/2014] [Accepted: 10/07/2014] [Indexed: 01/03/2023] Open
Abstract
A central pathological hallmark of Parkinson's disease (PD) is the presence of proteinaceous depositions known as Lewy bodies, which consist largely of the protein α-synuclein (aSyn). Mutations, multiplications and polymorphisms in the gene encoding aSyn are associated with familial forms of PD and susceptibility to idiopathic PD. Alterations in aSyn impair neuronal vesicle formation/transport, and likely contribute to PD pathogenesis by neuronal dysfunction and degeneration. aSyn is functionally associated with several Rab family GTPases, which perform various roles in vesicle trafficking. Here, we explore the role of the endosomal recycling factor Rab11 in the pathogenesis of PD using Drosophila models of aSyn toxicity. We find that aSyn induces synaptic potentiation at the larval neuromuscular junction by increasing synaptic vesicle (SV) size, and that these alterations are reversed by Rab11 overexpression. Furthermore, Rab11 decreases aSyn aggregation and ameliorates several aSyn-dependent phenotypes in both larvae and adult fruit flies, including locomotor activity, degeneration of dopaminergic neurons and shortened lifespan. This work emphasizes the importance of Rab11 in the modulation of SV size and consequent enhancement of synaptic function. Our results suggest that targeting Rab11 activity could have a therapeutic value in PD.
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Affiliation(s)
- Carlo Breda
- Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Marie L Nugent
- Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK, MRC Toxicology Unit, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - Jasper G Estranero
- Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK
| | | | - Tiago F Outeiro
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Goettingen, Göttingen, Germany and Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal
| | - Joern R Steinert
- MRC Toxicology Unit, University of Leicester, Lancaster Road, Leicester LE1 9HN, UK
| | - Flaviano Giorgini
- Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK,
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10
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Bhuin T, Roy JK. Rab11 in disease progression. INTERNATIONAL JOURNAL OF MOLECULAR AND CELLULAR MEDICINE 2015; 4:1-8. [PMID: 25815277 PMCID: PMC4359700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 11/24/2014] [Accepted: 12/16/2014] [Indexed: 10/26/2022]
Abstract
Membrane/protein trafficking in the secretory/biosynthetic and endocytic pathways is mediated by vesicles. Vesicle trafficking in eukaryotes is regulated by a class of small monomeric GTPases: the Rab protein family. Rab proteins represent the largest branch of the Ras superfamily GTPases, and have been concerned in a variety of intracellular vesicle trafficking and different intracellular signalling pathways. Rab11 (a subfamily of the Ypt/Rab gene family), an evolutionarily conserved ubiquitously expressed subfamily of Rab GTPases, has been implicated in regulating vesicular trafficking through the recycling of endosomes. Rabs have been grouped into different subfamilies based on the distinct unambiguous sequence motifs. Three members: Rab11a, Rab11b and Rab25 make up the Rab11 GTPase subfamily. In this review article, we describe an overview over Rab11 subfamily with a brief structural aspect and its roles in implicating different disease progression.
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Affiliation(s)
- Tanmay Bhuin
- Cell and Developmental Biology Unit, Department of Zoology, The University of Burdwan, Golapbag-713104, India.
| | - Jagat Kumar Roy
- Cytogenetics Laboratory, Department of Zoology, Banaras Hindu University, Varanasi-221 005, India.,Corresponding author: Cytogenetics Laboratory, Department of Zoology, Banaras Hindu University, Varanasi-221 005, India.
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11
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Robinson SW, Nugent ML, Dinsdale D, Steinert JR. Prion protein facilitates synaptic vesicle release by enhancing release probability. Hum Mol Genet 2014; 23:4581-96. [PMID: 24722203 PMCID: PMC4119408 DOI: 10.1093/hmg/ddu171] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The cellular prion protein (PrP(C)) has been implicated in several neurodegenerative diseases as a result of protein misfolding. In humans, prion disease occurs typically with a sporadic origin where uncharacterized mechanisms induce spontaneous PrP(C) misfolding leading to neurotoxic PrP-scrapie formation (PrP(SC)). The consequences of misfolded PrP(C) signalling are well characterized but little is known about the physiological roles of PrP(C) and its involvement in disease. Here we investigated wild-type PrP(C) signalling in synaptic function as well as the effects of a disease-relevant mutation within PrP(C) (proline-to-leucine mutation at codon 101). Expression of wild-type PrP(C) at the Drosophila neuromuscular junction leads to enhanced synaptic responses as detected in larger miniature synaptic currents which are caused by enlarged presynaptic vesicles. The expression of the mutated PrP(C) leads to reduction of both parameters compared with wild-type PrP(C). Wild-type PrP(C) enhances synaptic release probability and quantal content but reduces the size of the ready-releasable vesicle pool. Partially, these changes are not detectable following expression of the mutant PrP(C). A behavioural test revealed that expression of either protein caused an increase in locomotor activities consistent with enhanced synaptic release and stronger muscle contractions. Both proteins were sensitive to proteinase digestion. These data uncover new functions of wild-type PrP(C) at the synapse with a disease-relevant mutation in PrP(C) leading to diminished functional phenotypes. Thus, our data present essential new information possibly related to prion pathogenesis in which a functional synaptic role of PrP(C) is compromised due to its advanced conversion into PrP(SC) thereby creating a lack-of-function scenario.
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Affiliation(s)
- Susan W Robinson
- MRC Toxicology Unit, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Marie L Nugent
- MRC Toxicology Unit, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, UK Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - David Dinsdale
- MRC Toxicology Unit, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Joern R Steinert
- MRC Toxicology Unit, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, UK
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