1
|
Chang JL, Hinrich AJ, Roman B, Norrbom M, Rigo F, Marr RA, Norstrom EM, Hastings ML. Targeting Amyloid-β Precursor Protein, APP, Splicing with Antisense Oligonucleotides Reduces Toxic Amyloid-β Production. Mol Ther 2018; 26:1539-1551. [PMID: 29628304 DOI: 10.1016/j.ymthe.2018.02.029] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 02/21/2018] [Accepted: 02/27/2018] [Indexed: 12/22/2022] Open
Abstract
Alterations in amyloid beta precursor protein (APP) have been implicated in cognitive decline in Alzheimer's disease (AD), which is accelerated in Down syndrome/Trisomy 21 (DS/TS21), likely due to the extra copy of the APP gene, located on chromosome 21. Proteolytic cleavage of APP generates amyloid-β (Aβ) peptide, the primary component of senile plaques associated with AD. Reducing Aβ production is predicted to lower plaque burden and mitigate AD symptoms. Here, we designed a splice-switching antisense oligonucleotide (SSO) that causes skipping of the APP exon that encodes proteolytic cleavage sites required for Aβ peptide production. The SSO induced exon skipping in Down syndrome cell lines, resulting in a reduction of Aβ. Treatment of mice with the SSO resulted in widespread distribution in the brain accompanied by APP exon skipping and a reduction of Aβ. Overall, we show that an alternatively spliced isoform of APP encodes a cleavage-incompetent protein that does not produce Aβ peptide and that promoting the production of this isoform with an SSO can reduce Aβ in vivo. These findings demonstrate the utility of using SSOs to induce a spliced isoform of APP to reduce Aβ as a potential approach for treating AD.
Collapse
Affiliation(s)
- Jennifer L Chang
- Department of Cell Biology and Anatomy, Center for Genetic Diseases, Chicago Medical School and School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
| | - Anthony J Hinrich
- Department of Cell Biology and Anatomy, Center for Genetic Diseases, Chicago Medical School and School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
| | - Brandon Roman
- Department of Biological Sciences, DePaul University, Chicago, IL 60614, USA
| | | | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA 92010, USA
| | - Robert A Marr
- Department of Neuroscience, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
| | - Eric M Norstrom
- Department of Biological Sciences, DePaul University, Chicago, IL 60614, USA
| | - Michelle L Hastings
- Department of Cell Biology and Anatomy, Center for Genetic Diseases, Chicago Medical School and School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA.
| |
Collapse
|
2
|
Miller AJ, Roman B, Norstrom EM. Protein electrophoretic migration data from custom and commercial gradient gels. Data Brief 2016; 9:1-3. [PMID: 27622203 PMCID: PMC5007585 DOI: 10.1016/j.dib.2016.08.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [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: 07/06/2016] [Revised: 08/04/2016] [Accepted: 08/09/2016] [Indexed: 11/16/2022] Open
Abstract
This paper presents data related to the article “A method for easily customizable gradient gel electrophoresis” (A.J. Miller, B. Roman, E.M. Norstrom, 2016) [1]. Data is presented on the rate of electrophoretic migration of proteins in both hand-poured and commercially acquired acrylamide gradient gels. For each gel, migration of 9 polypeptides of various masses was measured upon completion of gel electrophoresis. Data are presented on the migration of proteins within separate lanes of the same gel as well as migration rates from multiple gels.
Collapse
Affiliation(s)
- Andrew J Miller
- Department of Biological Sciences, DePaul University, 2325 N. Clifton Ave, Chicago, IL 60614, USA
| | - Brandon Roman
- Department of Biological Sciences, DePaul University, 2325 N. Clifton Ave, Chicago, IL 60614, USA
| | - Eric M Norstrom
- Department of Biological Sciences, DePaul University, 2325 N. Clifton Ave, Chicago, IL 60614, USA
| |
Collapse
|
3
|
Philibert KD, Marr RA, Norstrom EM, Glucksman MJ. Identification and characterization of Aβ peptide interactors in Alzheimer's disease by structural approaches. Front Aging Neurosci 2014; 6:265. [PMID: 25346686 PMCID: PMC4191344 DOI: 10.3389/fnagi.2014.00265] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [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: 07/11/2014] [Accepted: 09/12/2014] [Indexed: 01/11/2023] Open
Abstract
Currently, there are very limited pharmaceutical interventions for Alzheimer's disease (AD) to alleviate the amyloid burden implicated in the pathophysiology of the disease. Alzheimer's disease is characterized immunohistologically by the accumulation of senile plaques in the brain with afflicted patients progressively losing short-term memory and, ultimately, cognition. Although significant improvements in clinical diagnosis and care for AD patients have been made, effective treatments for this devastating disease remain elusive. A key component of the amyloid burden of AD comes from accumulation of the amyloid-beta (Aβ) peptide which comes from processing of the amyloid precursor protein (APP) by enzymes termed secretases, leading to production of these toxic Aβ peptides of 40-42 amino acids. New therapeutic approaches for reducing Aβ are warranted after the most logical avenues of inhibiting secretase activity appear less than optimal in ameliorating the progression of AD.Novel therapeutics may be gleaned from proteomics biomarker initiatives to yield detailed molecular interactions of enzymes and their potential substrates. Explicating the APPome by deciphering protein complexes forming in cells is a complementary approach to unveil novel molecular interactions with the amyloidogenic peptide precursor to both understand the biology and develop potential upstream drug targets. Utilizing these strategies we have identified EC 3.4.24.15 (EP24.15), a zinc metalloprotease related to neprilysin (NEP), with the ability to catabolize Aβ 1-42 by examining first potential in silico docking and then verification by mass spectrometry. In addition, a hormone carrier protein, transthyreitin (TTR), was identified and with its abundance in cerebrospinal fluid (CSF), found to clear Aβ by inhibiting formation of oligomeric forms of Aβ peptide. The confluence of complementary strategies may allow new therapeutic avenues as well as biomarkers for AD that will aid in diagnosis, prognosis and treatment.
Collapse
Affiliation(s)
- Keith D Philibert
- Department of Biochemistry and Molecular Biology, Chicago Medical School, Rosalind Franklin University of Medicine and Science North Chicago, IL, USA
| | - Robert A Marr
- Department of Neuroscience, Chicago Medical School, Rosalind Franklin University of Medicine and Science North Chicago, IL, USA
| | - Eric M Norstrom
- Department of Biological Sciences, DePaul University Chicago, IL, USA
| | - Marc J Glucksman
- Department of Biochemistry and Molecular Biology, Chicago Medical School, Rosalind Franklin University of Medicine and Science North Chicago, IL, USA
| |
Collapse
|
4
|
Mallik S, Yang W, Norstrom EM, Mastrianni JA. Live cell fluorescence resonance energy transfer predicts an altered molecular association of heterologous PrPSc with PrPC. J Biol Chem 2010; 285:8967-75. [PMID: 20086009 DOI: 10.1074/jbc.m109.058107] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Prion diseases result from the accumulation of a misfolded isoform (PrP(Sc)) of the normal host prion protein (PrP(C)). PrP(Sc) propagates by templating its conformation onto resident PrP(C) to generate new PrP(Sc). Although the nature of the PrP(Sc)-PrP(C) complex is unresolved, certain segments or specific residues are thought to feature critically in its formation. The polymorphic residue 129 is one such site under considerable study. We combined transmission studies with a novel live cell yeast-based fluorescence resonance energy transfer (FRET) system that models the molecular association of PrP in a PrP(Sc)-like state, as a way to explore the role of residue 129 in this process. We show that a reduction in efficiency of prion transmission between donor PrP(Sc) and recipient PrP(C) that are mismatched at residue 129 correlates with a reduction in FRET between PrP-129M and PrP-129V in our yeast model. We further show that this effect depends on the different secondary structure propensities of Met and Val, rather than the specific amino acids. Finally, introduction of the disease-associated P101L mutation (mouse- equivalent) abolished FRET with wild-type mouse PrP, whereas mutant PrP-P101L displayed high FRET with homologous PrP-P101L, as long as residue 129 matched. These studies provide the first evidence for a physical alteration in the molecular association of PrP molecules differing in one or more residues, and they further predict that the different secondary structure propensities of Met and Val define the impaired association observed between PrP(Sc) and PrP(C) mismatched at residue 129.
Collapse
Affiliation(s)
- Suparna Mallik
- Department of Neurology, The University of Chicago, Chicago, Illinois 60637, USA
| | | | | | | |
Collapse
|
5
|
Meier M, Kennedy-Darling J, Choi SH, Norstrom EM, Sisodia SS, Ismagilov RF. Plug-based microfluidics with defined surface chemistry to miniaturize and control aggregation of amyloidogenic peptides. Angew Chem Int Ed Engl 2009; 48:1487-9. [PMID: 19152390 DOI: 10.1002/anie.200805225] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Small with control: For miniaturization of protein aggregation experiments the interfacial chemistry must be controlled to avoid protein aggregation caused by interfacial adsorption. Plug-based microfluidics with defined surface chemistry (see schematic picture) can then be used to perform hundreds of aggregation experiments with volume-limited samples, such as cerebrospinal fluid from mice.
Collapse
Affiliation(s)
- Matthias Meier
- Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, IL 60637, USA
| | | | | | | | | | | |
Collapse
|
6
|
Mirnics K, Norstrom EM, Garbett K, Choi SH, Zhang X, Ebert P, Sisodia SS. Molecular signatures of neurodegeneration in the cortex of PS1/PS2 double knockout mice. Mol Neurodegener 2008; 3:14. [PMID: 18834536 PMCID: PMC2569036 DOI: 10.1186/1750-1326-3-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [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: 06/25/2008] [Accepted: 10/03/2008] [Indexed: 11/10/2022] Open
Abstract
Background Familial Alzheimer's disease-linked variants of presenilin (PSEN1 and PSEN2) contribute to the pathophysiology of disease by both gain-of-function and loss-of-function mechanisms. Deletions of PSEN1 and PSEN2 in the mouse forebrain result in a strong and progressive neurodegenerative phenotype which is characterized by both anatomical and behavioral changes. Results To better understand the molecular changes associated with these morphological and behavioral phenotypes, we performed a DNA microarray transcriptome profiling of the hippocampus and the frontal cortex of the PSEN1/PSEN2 double knock-out mice and littermate controls at five different ages ranging from 2–8 months. Our data suggest that combined deficiencies of PSEN1 and PSEN2 results in a progressive, age-dependent transcriptome signature related to neurodegeneration and neuroinflammation. While these events may progress differently in the hippocampus and frontal cortex, the most critical expression signatures are common across the two brain regions, and involve a strong upregulation of cathepsin and complement system transcripts. Conclusion The observed neuroinflammatory expression changes are likely to be causally linked to the neurodegenerative phenotype observed in mice with compound deletions of PSEN1 and PSEN2. Furthermore, our results suggest that the evaluation of inhibitors of PS/γ-secretase activity for treatment of Alzheimer's Disease must include close monitoring for signs of calpain-cathepsin system activation.
Collapse
Affiliation(s)
- Károly Mirnics
- Department of Psychiatry, Vanderbilt University, Nashville, TN37232, USA.
| | | | | | | | | | | | | |
Collapse
|
7
|
Norstrom EM, Ciaccio MF, Rassbach B, Wollmann R, Mastrianni JA. Cytosolic prion protein toxicity is independent of cellular prion protein expression and prion propagation. J Virol 2006; 81:2831-7. [PMID: 17182694 PMCID: PMC1866012 DOI: 10.1128/jvi.02157-06] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [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] [Indexed: 11/20/2022] Open
Abstract
Prion diseases are transmissible neurodegenerative diseases caused by a conformational isoform of the prion protein (PrP), a host-encoded cell surface sialoglycoprotein. Recent evidence suggests a cytosolic fraction of PrP (cyPrP) functions either as an initiating factor or toxic element of prion disease. When expressed in cultured cells, cyPrP acquires properties of the infectious conformation of PrP (PrP(Sc)), including insolubility, protease resistance, aggregation, and toxicity. Transgenic mice (2D1 and 1D4 lines) that coexpress cyPrP and PrP(C) exhibit focal cerebellar atrophy, scratching behavior, and gait abnormalities suggestive of prion disease, although they lack protease-resistant PrP. To determine if the coexpression of PrP(C) is necessary or inhibitory to the phenotype of these mice, we crossed Tg1D4(Prnp(+/+)) mice with PrP-ablated mice (TgPrnp(o/o)) to generate Tg1D4(Prnp(o/o)) mice and followed the development of disease and pathological phenotype. We found no difference in the onset of symptoms or the clinical or pathological phenotype of disease between Tg1D4(Prnp(+/+)) and Tg1D4(Prnp(o/o)) mice, suggesting that cyPrP and PrP(C) function independently in the disease state. Additionally, Tg1D4(Prnp(o/o)) mice were resistant to challenge with mouse-adapted scrapie (RML), suggesting cyPrP is inaccessible to PrP(Sc). We conclude that disease phenotype and cellular toxicity associated with the expression of cyPrP are independent of PrP(C) and the generation of typical prion disease.
Collapse
Affiliation(s)
- Eric M Norstrom
- Department of Neurology, University of Chicago, MC2030, 5841 South Maryland Avenue, Chicago, IL 60637, USA
| | | | | | | | | |
Collapse
|
8
|
Abstract
The prion diseases are transmissible neurodegenerative disorders linked to a pathogenic conformer (PrP(Sc)) of the normal prion protein (PrP(C)). Accumulation of PrP(Sc) occurs via a poorly defined process in which PrP(Sc) complexes with and converts endogenous PrP(C) to nascent PrP(Sc). Recent experiments have focused on the highly charged first alpha helix (H1) of PrP. It has been proposed that two putative asparagine-to-arginine intrahelical salt bridges stabilize H1 in PrP(C) yet form intermolecular ionic bonds with adjacent PrP molecules during conversion of PrP(C) to PrP(Sc) (M. P. Morrissey and E. I. Shakhnovich, Proc. Natl. Acad. Sci. USA 96:11293-11298, 1999). Subsequent work (J. O. Speare et al., J. Biol. Chem. 278:12522-12529, 2003 using a cell-free assay of PrP(Sc) conversion suggested that rather than promoting conversion, the salt bridges stabilize PrP(C) against it. However, the role of individual H1 charges in PrP(Sc) generation has not yet been investigated. To approach this question, we systematically reversed or neutralized each charged residue in H1 and tested the effect on conversion to PrP(Sc) in scrapie-infected murine neuroblastoma (ScN2a) cells. We find that replacements of charged H1 residues with like charges permit conversion, while charge reversals hinder it. Neutralization of charges in the N-terminal (amino acids 143 to 146) but not the C-terminal (amino acids 147 to 151) half of H1 permits conversion, while complete reversal of charge orientation of the putative salt bridges produces a nonconvertible PrP. Circular dichroism spectroscopy studies and confocal microscopy immunofluorescence localization studies indicated that charge substitutions did not alter the secondary structure or cell surface expression of PrP(C). These data support the necessity of specific charge orientations in H1 for a productive PrP(Sc)-PrP(C) complex.
Collapse
Affiliation(s)
- Eric M Norstrom
- The Committee on Neurobiology, The University of Chicago, Illinois 60637, USA
| | | |
Collapse
|
9
|
Norstrom EM, Mastrianni JA. The AGAAAAGA palindrome in PrP is required to generate a productive PrPSc-PrPC complex that leads to prion propagation. J Biol Chem 2005; 280:27236-43. [PMID: 15917252 DOI: 10.1074/jbc.m413441200] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [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] [Indexed: 11/06/2022] Open
Abstract
The molecular hallmark of prion disease is the conversion of normal prion protein (PrPC) to an insoluble, proteinase K-resistant, pathogenic isoform (PrPSc). Once generated, PrPSc propagates by complexing with, and transferring its pathogenic conformation onto, PrPC. Defining the specific nature of this PrPSc-PrPC interaction is critical to understanding prion genesis. To begin to approach this question, we employed a prion-infected neuroblastoma cell line (ScN2a) combined with a heterologous yeast expression system to independently model PrPSc generation and propagation. We additionally applied fluorescence resonance energy transfer analysis to the latter to specifically study PrP-PrP interactions. In this report we focus on an N-terminal hydrophobic palindrome of PrP (112-AGAAAAGA-119) thought to feature intimately in prion generation via an unclear mechanism. We found that, in contrast to wild type (wt) PrP, PrP lacking the palindrome (PrPDelta112-119) neither converted to PrPSc when expressed in ScN2a cells nor generated proteinase K-resistant PrP when expressed in yeast. Furthermore, PrPDelta112-119 was a dominant-negative inhibitor of wtPrP in ScN2a cells. Both wtPrP and PrPDelta112-119 were highly insoluble when expressed in yeast and produced distinct cytosolic aggregates when expressed as fluorescent fusion proteins (PrP::YFP). Although self-aggregation was evident, fluorescence resonance energy transfer studies in live yeast co-expressing PrPSc-like protein and PrPDelta112-119 indicated altered interaction properties. These results suggest that the palindrome is required, not only for the attainment of the PrPSc conformation but also to facilitate the proper association of PrPSc with PrPC to effect prion propagation.
Collapse
Affiliation(s)
- Eric M Norstrom
- Committee on Neurobiology and Department of Neurology, The University of Chicago, Chicago, Illinois 60637, USA
| | | |
Collapse
|