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Hodges ED, Chrystal PW, Footz T, Doucette LP, Noel NCL, Li Z, Walter MA, Allison WT. Disrupting the Repeat Domain of Premelanosome Protein (PMEL) Produces Dysamyloidosis and Dystrophic Ocular Pigment Reflective of Pigmentary Glaucoma. Int J Mol Sci 2023; 24:14423. [PMID: 37833870 PMCID: PMC10572516 DOI: 10.3390/ijms241914423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 09/11/2023] [Accepted: 09/14/2023] [Indexed: 10/15/2023] Open
Abstract
Pigmentary glaucoma has recently been associated with missense mutations in PMEL that are dominantly inherited and enriched in the protein's fascinating repeat domain. PMEL pathobiology is intriguing because PMEL forms functional amyloid in healthy eyes, and this PMEL amyloid acts to scaffold melanin deposition. This is an informative contradistinction to prominent neurodegenerative diseases where amyloid formation is neurotoxic and mutations cause a toxic gain of function called "amyloidosis". Preclinical animal models have failed to model this PMEL "dysamyloidosis" pathomechanism and instead cause recessively inherited ocular pigment defects via PMEL loss of function; they have not addressed the consequences of disrupting PMEL's repetitive region. Here, we use CRISPR to engineer a small in-frame mutation in the zebrafish homolog of PMEL that is predicted to subtly disrupt the protein's repetitive region. Homozygous mutant larvae displayed pigmentation phenotypes and altered eye morphogenesis similar to presumptive null larvae. Heterozygous mutants had disrupted eye morphogenesis and disrupted pigment deposition in their retinal melanosomes. The deficits in the pigment deposition of these young adult fish were not accompanied by any detectable glaucomatous changes in intraocular pressure or retinal morphology. Overall, the data provide important in vivo validation that subtle PMEL mutations can cause a dominantly inherited pigment pathology that aligns with the inheritance of pigmentary glaucoma patient pedigrees. These in vivo observations help to resolve controversy regarding the necessity of PMEL's repeat domain in pigmentation. The data foster an ongoing interest in an antithetical dysamyloidosis mechanism that, akin to the amyloidosis of devastating dementias, manifests as a slow progressive neurodegenerative disease.
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Affiliation(s)
- Elizabeth D. Hodges
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; (E.D.H.); (P.W.C.)
- Faculty of Science, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Paul W. Chrystal
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; (E.D.H.); (P.W.C.)
- Department of Cell & Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Tim Footz
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2R3, Canada (M.A.W.)
| | - Lance P. Doucette
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; (E.D.H.); (P.W.C.)
| | - Nicole C. L. Noel
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; (E.D.H.); (P.W.C.)
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2R3, Canada (M.A.W.)
- Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Zixuan Li
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; (E.D.H.); (P.W.C.)
| | - Michael A. Walter
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2R3, Canada (M.A.W.)
| | - W. Ted Allison
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; (E.D.H.); (P.W.C.)
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2R3, Canada (M.A.W.)
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada
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2
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Onur P, Shaver M, Iqbal MA. Interstitial 20p13 microdeletion including PRNP and adjacent genes in a fetus with congenital abnormalities-First case report. Clin Case Rep 2021; 9:e04082. [PMID: 34084500 PMCID: PMC8142463 DOI: 10.1002/ccr3.4082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 01/31/2021] [Accepted: 02/22/2021] [Indexed: 11/11/2022] Open
Abstract
We present a prenatal case with congenital anomalies that revealed a 759 kb microdeletion at 20p13 possibly implicating PRNP and adjacent genes.
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Affiliation(s)
- Pelin Onur
- Pathology and Laboratory MedicineUniversity of Rochester Medical CenterRochesterNYUSA
| | - Mary Shaver
- Pathology and Laboratory MedicineUniversity of Rochester Medical CenterRochesterNYUSA
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3
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Kanyo R, Leighton PLA, Neil GJ, Locskai LF, Allison WT. Amyloid-β precursor protein mutant zebrafish exhibit seizure susceptibility that depends on prion protein. Exp Neurol 2020; 328:113283. [PMID: 32165257 DOI: 10.1016/j.expneurol.2020.113283] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 02/03/2020] [Accepted: 03/08/2020] [Indexed: 12/11/2022]
Abstract
It has been proposed that Amyloid β Precursor Protein (APP) might act as a rheostat controlling neuronal excitability, but mechanisms have remained untested. APP and its catabolite Aβ are known to impact upon synapse function and dysfunction via their interaction with the prion protein (PrPC), suggesting a candidate pathway. Here we test if PrPC is required for this APP function in vivo, perhaps via modulating mGluR5 ion channels. We engineered zebrafish to lack homologs of PrPC and APP, allowing us to assess their purported genetic and physiological interactions in CNS development. We generated four appa null alleles as well as prp1-/-;appa-/- double mutants (engineering of prp1 mutant alleles is described elsewhere). Unexpectedly, appa-/- and compound prp1-/-;appa-/- mutants are viable and lacked overt phenotypes (except being slightly smaller than wildtype fish at some developmental stages). Zebrafish prp1-/- mutants were substantially more sensitive to appa knockdown than wildtype fish, and both zebrafish prp1 and mammalian Prnp mRNA were significantly able to partially rescue this effect. Further, appa-/- mutants exhibited increased seizures upon exposure to low doses of convulsant. The mechanism of this seizure susceptibility requires prp1 insomuch that seizures were significantly dampened to wildtype levels in prp1-/-;appa-/- mutants. Inhibiting mGluR5 channels, which may be downstream of PrPC, increased seizure intensity only in prp1-/- mutants, and this seizure mechanism required intact appa. Taken together, these results support an intriguing genetic interaction between prp1 and appa with their shared roles impacting upon neuron hyperexcitability, thus complementing and extending past works detailing their biochemical interaction(s).
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Affiliation(s)
- Richard Kanyo
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Patricia L A Leighton
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Gavin J Neil
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Laszlo F Locskai
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - W Ted Allison
- Centre for Prions & Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada; Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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4
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Lahola-Chomiak AA, Footz T, Nguyen-Phuoc K, Neil GJ, Fan B, Allen KF, Greenfield DS, Parrish RK, Linkroum K, Pasquale LR, Leonhardt RM, Ritch R, Javadiyan S, Craig JE, Allison WT, Lehmann OJ, Walter MA, Wiggs JL. Non-Synonymous variants in premelanosome protein (PMEL) cause ocular pigment dispersion and pigmentary glaucoma. Hum Mol Genet 2019; 28:1298-1311. [PMID: 30561643 DOI: 10.1093/hmg/ddy429] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/04/2018] [Accepted: 12/12/2018] [Indexed: 01/25/2023] Open
Abstract
Pigmentary glaucoma (PG) is a common glaucoma subtype that results from release of pigment from the iris, called pigment dispersion syndrome (PDS), and its deposition throughout the anterior chamber of the eye. Although PG has a substantial heritable component, no causative genes have yet been identified. We used whole exome sequencing of two independent pedigrees to identify two premelanosome protein (PMEL) variants associated with heritable PDS/PG. PMEL encodes a key component of the melanosome, the organelle essential for melanin synthesis, storage and transport. Targeted screening of PMEL in three independent cohorts (n = 394) identified seven additional PDS/PG-associated non-synonymous variants. Five of the nine variants exhibited defective processing of the PMEL protein. In addition, analysis of PDS/PG-associated PMEL variants expressed in HeLa cells revealed structural changes to pseudomelanosomes indicating altered amyloid fibril formation in five of the nine variants. Introduction of 11-base pair deletions to the homologous pmela in zebrafish by the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 method caused profound pigmentation defects and enlarged anterior segments in the eye, further supporting PMEL's role in ocular pigmentation and function. Taken together, these data support a model in which missense PMEL variants represent dominant negative mutations that impair the ability of PMEL to form functional amyloid fibrils. While PMEL mutations have previously been shown to cause pigmentation and ocular defects in animals, this research is the first report of mutations in PMEL causing human disease.
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Affiliation(s)
| | - Tim Footz
- Department of Medical Genetics, University of Alberta, Edmonton AB, Canada
| | - Kim Nguyen-Phuoc
- Department of Medical Genetics, University of Alberta, Edmonton AB, Canada
| | - Gavin J Neil
- Department of Biological Sciences, University of Alberta, Edmonton AB, Canada
| | - Baojian Fan
- Ocular Genomics Institute and Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Keri F Allen
- Ocular Genomics Institute and Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - David S Greenfield
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Palm Beach Gardens, FL, USA
| | - Richard K Parrish
- Anne Bates Leach Eye Hospital, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Kevin Linkroum
- Ocular Genomics Institute and Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Louis R Pasquale
- Ocular Genomics Institute and Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Ralf M Leonhardt
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Robert Ritch
- Einhorn Clinical Research Center, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA
| | - Shari Javadiyan
- Department of Ophthalmology, Flinders Medical Centre, Adelaide, South Australia, Australia
| | - Jamie E Craig
- Department of Ophthalmology, Flinders Medical Centre, Adelaide, South Australia, Australia
| | - W T Allison
- Department of Medical Genetics, University of Alberta, Edmonton AB, Canada.,Department of Biological Sciences, University of Alberta, Edmonton AB, Canada
| | - Ordan J Lehmann
- Department of Medical Genetics, University of Alberta, Edmonton AB, Canada.,Department of Ophthalmology, University of Alberta, Edmonton AB, Canada
| | - Michael A Walter
- Department of Medical Genetics, University of Alberta, Edmonton AB, Canada
| | - Janey L Wiggs
- Ocular Genomics Institute and Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
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Wells C, Brennan SE, Keon M, Saksena NK. Prionoid Proteins in the Pathogenesis of Neurodegenerative Diseases. Front Mol Neurosci 2019; 12:271. [PMID: 31780895 PMCID: PMC6861308 DOI: 10.3389/fnmol.2019.00271] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 10/23/2019] [Indexed: 12/13/2022] Open
Abstract
There is a growing body of evidence that prionoid protein behaviors are a core element of neurodegenerative diseases (NDs) that afflict humans. Common elements in pathogenesis, pathological effects and protein-level behaviors exist between Alzheimer's Disease (AD), Parkinson's Disease (PD), Huntington's Disease (HD) and Amyotrophic Lateral Sclerosis (ALS). These extend beyond the affected neurons to glial cells and processes. This results in a complicated system of disease progression, which often takes advantage of protective processes to promote the propagation of pathological protein aggregates. This review article provides a current snapshot of knowledge on these proteins and their intrinsic role in the pathogenesis and disease progression seen across NDs.
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Tryptophan 32 mediates SOD1 toxicity in a in vivo motor neuron model of ALS and is a promising target for small molecule therapeutics. Neurobiol Dis 2018; 124:297-310. [PMID: 30528257 DOI: 10.1016/j.nbd.2018.11.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 11/11/2018] [Accepted: 11/28/2018] [Indexed: 12/21/2022] Open
Abstract
SOD1 misfolding, toxic gain of function, and spread are proposed as a pathological basis of amyotrophic lateral sclerosis (ALS), but the nature of SOD1 toxicity has been difficult to elucidate. Uniquely in SOD1 proteins from humans and other primates, and rarely in other species, a tryptophan residue at position 32 (W32) is predicted to be solvent exposed and to participate in SOD1 misfolding. We hypothesized that W32 is influential in SOD1 acquiring toxicity, as it is known to be important in template-directed misfolding. We tested if W32 contributes to SOD1 cytotoxicity and if it is an appropriate drug target to ameliorate ALS-like neuromuscular deficits in a zebrafish model of motor neuron axon morphology and function (swimming). Embryos injected with human SOD1 variant with W32 substituted for a serine (SOD1W32S) had reduced motor neuron axonopathy and motor deficits compared to those injected with wildtype or disease-associated SOD1. A library of FDA-approved small molecules was ranked with virtual screening based on predicted binding to W32, and subsequently filtered for analogues using a pharmacophore model based on molecular features of the uracil moiety of a small molecule previously predicted to interact with W32 (5'-fluorouridine or 5'-FUrd). Along with testing 5'-FUrd and uridine, a lead candidate from this list was selected based on its lower toxicity and improved blood brain barrier penetrance; telbivudine significantly rescued SOD1 toxicity in a dose-dependent manner. The mechanisms whereby the small molecules ameliorated motor neuron phenotypes were specifically mediated through human SOD1 and its residue W32, because these therapeutics had no measurable impact on the effects of UBQLN4D90A, EtOH, or tryptophan-deficient human SOD1W32S. By substituting W32 for a more evolutionarily conserved residue (serine), we confirmed the significant influence of W32 on human SOD1 toxicity to motor neuron morphology and function; further, we performed pharmaceutical targeting of the W32 residue for rescuing SOD1 toxicity. This unique residue offers future novel insights into SOD1 stability and toxic gain of function, and therefore poses an potential target for drug therapy.
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Leighton PLA, Kanyo R, Neil GJ, Pollock NM, Allison WT. Prion gene paralogs are dispensable for early zebrafish development and have nonadditive roles in seizure susceptibility. J Biol Chem 2018; 293:12576-12592. [PMID: 29903907 DOI: 10.1074/jbc.ra117.001171] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 06/07/2018] [Indexed: 11/06/2022] Open
Abstract
Normally folded prion protein (PrPC) and its functions in healthy brains remain underappreciated compared with the intense study of its misfolded forms ("prions," PrPSc) during the pathobiology of prion diseases. This impedes the development of therapeutic strategies in Alzheimer's and prion diseases. Disrupting the zebrafish homologs of PrPC has provided novel insights; however, mutagenesis of the zebrafish paralog prp2 did not recapitulate previous dramatic developmental phenotypes, suggesting redundancy with the prp1 paralog. Here, we generated zebrafish prp1 loss-of-function mutant alleles and dual prp1-/-;prp2-/- mutants. Zebrafish prp1-/- and dual prp1-/-;prp2-/- mutants resemble mammalian Prnp knockouts insofar as they lack overt phenotypes, which surprisingly contrasts with reports of severe developmental phenotypes when either prp1 or prp2 is knocked down acutely. Previous studies suggest that PrPC participates in neural cell development/adhesion, including in zebrafish where loss of prp2 affects adhesion and deposition patterns of lateral line neuromasts. In contrast with the expectation that prp1's functions would be redundant to prp2, they appear to have opposing functions in lateral line neurodevelopment. Similarly, loss of prp1 blunted the seizure susceptibility phenotypes observed in prp2 mutants, contrasting the expected exacerbation of phenotypes if these prion gene paralogs were serving redundant roles. In summary, prion mutant fish lack the overt phenotypes previously predicted, and instead they have subtle phenotypes similar to mammals. No evidence was found for functional redundancy in the zebrafish prion gene paralogs, and the phenotypes observed when each gene is disrupted individually are consistent with ancient functions of prion proteins in neurodevelopment and modulation of neural activity.
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Affiliation(s)
- Patricia L A Leighton
- From the Department of Biological Sciences and the Centre for Prion and Protein Folding Diseases, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Richard Kanyo
- From the Department of Biological Sciences and the Centre for Prion and Protein Folding Diseases, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Gavin J Neil
- From the Department of Biological Sciences and the Centre for Prion and Protein Folding Diseases, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Niall M Pollock
- From the Department of Biological Sciences and the Centre for Prion and Protein Folding Diseases, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - W Ted Allison
- From the Department of Biological Sciences and the Centre for Prion and Protein Folding Diseases, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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8
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Allison WT. The intrigue is infectious: Impacts of prion protein during neural development. Dev Biol 2018; 441:1-3. [PMID: 29803646 DOI: 10.1016/j.ydbio.2018.05.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 05/20/2018] [Accepted: 05/23/2018] [Indexed: 10/16/2022]
Abstract
Normally folded prion protein is abundant in the CNS and remarkably conserved, suggesting that it has important functions, yet these functions have remained elusive. Now the work of Parrie et al. has codified a requirement for prion protein in adult neurogenesis. Their insightful use of prion protein knockout and over-expressing mice, combined with the well-characterized olfactory system site of neurogenesis, demonstrated that prion protein promotes proliferation and survival of adult neurons. The work provides a unique independent confirmation of prion protein playing a role in neuroprotection, especially extending the conclusion beyond models using acute injury. Parrie et al. (2018) further show that prion protein is required for CNS axon guidance. A growing list of phenotypes associated with prion protein loss are coincident with symptoms of neurodegenerative disease and dementia, though it remains contentious whether any such disruption of prion protein function contributes to disease aetiology. Perhaps most intriguingly, identifying the developmental functions for prion protein opens new avenues to understand the evolution of prion protein: what history led to a CNS protein that is conserved and abundant paradoxically being both dispensable for life and the template for devastating disease?
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Affiliation(s)
- W Ted Allison
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada T6G 2M8; Department of Biological Sciences, University of Alberta, Edmonton, Canada T6G 2E9; Department of Medical Genetics, University of Alberta, Edmonton, Canada T6G 2H7.
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Leighton PLA, Nadolski NJ, Morrill A, Hamilton TJ, Allison WT. An ancient conserved role for prion protein in learning and memory. Biol Open 2018; 7:bio.025734. [PMID: 29358166 PMCID: PMC5829491 DOI: 10.1242/bio.025734] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The misfolding of cellular prion protein (PrPC) to form PrP Scrapie (PrPSc) is an exemplar of toxic gain-of-function mechanisms inducing propagated protein misfolding and progressive devastating neurodegeneration. Despite this, PrPC function in the brain is also reduced and subverted during prion disease progression; thus understanding the normal function of PrPC in healthy brains is key. Disrupting PrPC in mice has led to a myriad of controversial functions that sometimes map onto disease symptoms, including a proposed role in memory or learning. Intriguingly, PrPC interaction with amyloid beta (Aβ) oligomers at synapses has also linked its function to Alzheimer's disease and dementia in recent years. We set out to test the involvement of PrPC in memory using a disparate animal model, the zebrafish. Here we document an age-dependent memory decline in prp2−/− zebrafish, pointing to a conserved and ancient role of PrPC in memory. Specifically, we found that aged (3-year-old) prp2−/− fish performed poorly in an object recognition task relative to age-matched prp2+/+ fish or 1-year-old prp2−/− fish. Further, using a novel object approach (NOA) test, we found that aged (3-year-old) prp2−/− fish approached the novel object more than either age-matched prp2+/+ fish or 1-year-old prp2−/− fish, but did not have decreased anxiety when we tested them in a novel tank diving test. Taken together, the results of the NOA and novel tank diving tests suggest an altered cognitive appraisal of the novel object in the 3-year-old prp2−/− fish. The learning paradigm established here enables a path forward to study PrPC interactions of relevance to Alzheimer's disease and prion diseases, and to screen for candidate therapeutics for these diseases. The findings underpin a need to consider the relative contributions of loss- versus gain-of-function of PrPC during Alzheimer's and prion diseases, and have implications upon the prospects of several promising therapeutic strategies. Summary: Prion protein dysfunction at the synapse impacts learning in Alzheimer disease. Here, we demonstrate similar roles for prion protein in zebrafish, revealing ancient constructive roles for this infamously toxic protein.
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Affiliation(s)
- Patricia L A Leighton
- Centre for Prions and Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada.,Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Nathan J Nadolski
- Department of Psychology, MacEwan University, Edmonton, AB T5J 4S2, Canada
| | - Adam Morrill
- Department of Psychology, MacEwan University, Edmonton, AB T5J 4S2, Canada
| | - Trevor J Hamilton
- Department of Psychology, MacEwan University, Edmonton, AB T5J 4S2, Canada .,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1
| | - W Ted Allison
- Centre for Prions and Protein Folding Disease, University of Alberta, Edmonton, AB T6G 2M8, Canada .,Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1.,Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 2H7, Canada
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