1
|
Zoltowska KM, Das U, Lismont S, Enzlein T, Maesako M, Houser MCQ, Franco ML, Özcan B, Moreira DG, Karachentsev D, Becker A, Hopf C, Vilar M, Berezovska O, Mobley W, Chávez-Gutiérrez L. Alzheimer's disease linked Aβ42 exerts product feedback inhibition on γ-secretase impairing downstream cell signaling. bioRxiv 2024:2023.08.02.551596. [PMID: 37577527 PMCID: PMC10418207 DOI: 10.1101/2023.08.02.551596] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Amyloid β (Aβ) peptides accumulating in the brain are proposed to trigger Alzheimer's disease (AD). However, molecular cascades underlying their toxicity are poorly defined. Here, we explored a novel hypothesis for Aβ42 toxicity that arises from its proven affinity for γ-secretases. We hypothesized that the reported increases in Aβ42, particularly in the endolysosomal compartment, promote the establishment of a product feedback inhibitory mechanism on γ-secretases, and thereby impair downstream signaling events. We show that human Aβ42 peptides, but neither murine Aβ42 nor human Aβ17-42 (p3), inhibit γ-secretases and trigger accumulation of unprocessed substrates in neurons, including C-terminal fragments (CTFs) of APP, p75 and pan-cadherin. Moreover, Aβ42 treatment dysregulated cellular -homeostasis, as shown by the induction of p75-dependent neuronal death in two distinct cellular systems. Our findings raise the possibility that pathological elevations in Aβ42 contribute to cellular toxicity via the γ-secretase inhibition, and provide a novel conceptual framework to address Aβ toxicity in the context of γ-secretase-dependent homeostatic signaling.
Collapse
Affiliation(s)
| | - Utpal Das
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Sam Lismont
- VIB-KU Leuven Center for Brain & Disease Research, VIB, Leuven, Belgium
| | - Thomas Enzlein
- VIB-KU Leuven Center for Brain & Disease Research, VIB, Leuven, Belgium
- Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Mannheim, Germany
| | - Masato Maesako
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA, United States of America
| | - Mei CQ Houser
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA, United States of America
| | - María Luisa Franco
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València (IBV-CSIC), València, Spain
| | - Burcu Özcan
- VIB-KU Leuven Center for Brain & Disease Research, VIB, Leuven, Belgium
| | | | - Dmitry Karachentsev
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Ann Becker
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | - Carsten Hopf
- Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Mannheim, Germany
- Medical Faculty, Heidelberg University, Heidelberg, Germany
- Mannheim Center for Translational Neuroscience (MCTN), Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Marçal Vilar
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València (IBV-CSIC), València, Spain
| | - Oksana Berezovska
- Department of Neurology, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA, United States of America
| | - William Mobley
- Department of Neurosciences, University of California San Diego, La Jolla, CA, United States of America
| | | |
Collapse
|
2
|
Serneels L, Bammens L, Zwijsen A, Tolia A, Chávez-Gutiérrez L, De Strooper B. Functional and topological analysis of PSENEN, the fourth subunit of the γ-secretase complex. J Biol Chem 2024; 300:105533. [PMID: 38072061 PMCID: PMC10790097 DOI: 10.1016/j.jbc.2023.105533] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/20/2023] [Accepted: 11/26/2023] [Indexed: 01/01/2024] Open
Abstract
The γ-secretase complexes are intramembrane cleaving proteases involved in the generation of the Aβ peptides in Alzheimer's disease. The complex consists of four subunits, with Presenilin harboring the catalytic site. Here, we study the role of the smallest subunit, PSENEN or Presenilin enhancer 2, encoded by the gene Psenen, in vivo and in vitro. We find a profound Notch deficiency phenotype in Psenen-/- embryos confirming the essential role of PSENEN in the γ-secretase complex. We used Psenen-/- fibroblasts to explore the structure-function of PSENEN by the scanning cysteine accessibility method. Glycine 22 and proline 27, which border the membrane domains 1 and 2 of PSENEN, are involved in complex formation and stabilization of γ-secretase. The hairpin structured hydrophobic membrane domains 1 and 2 are exposed to a water-containing cavity in the complex, while transmembrane domain 3 is not water exposed. We finally demonstrate the essential role of PSENEN for the cleavage activity of the complex. PSENEN is more than a structural component of the γ-secretase complex and might contribute to the catalytic mechanism of the enzyme.
Collapse
Affiliation(s)
- Lutgarde Serneels
- Laboratory for the Research of Neurodegenerative Diseases, VIB Center for Brain & Disease Research, VIB, Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Leen Bammens
- Laboratory for the Research of Neurodegenerative Diseases, VIB Center for Brain & Disease Research, VIB, Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - An Zwijsen
- Laboratory of Developmental Signaling, Center for Human Genetics, KU Leuven, Leuven, Belgium
| | - Alexandra Tolia
- Laboratory for the Research of Neurodegenerative Diseases, VIB Center for Brain & Disease Research, VIB, Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Lucía Chávez-Gutiérrez
- Laboratory for the Research of Neurodegenerative Diseases, VIB Center for Brain & Disease Research, VIB, Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, Leuven, Belgium
| | - Bart De Strooper
- Laboratory for the Research of Neurodegenerative Diseases, VIB Center for Brain & Disease Research, VIB, Leuven, Belgium; Department of Neurosciences and Leuven Brain Institute, KU Leuven, Leuven, Belgium.
| |
Collapse
|
3
|
Chen SY, Koch M, Chávez-Gutiérrez L, Zacharias M. How Modulator Binding at the Amyloidβ-γ-Secretase Interface Enhances Substrate Binding and Attenuates Membrane Distortion. J Med Chem 2023; 66:16772-16782. [PMID: 38059872 DOI: 10.1021/acs.jmedchem.3c01480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Inhibition of γ-secretase, an intramembrane protease, to reduce secretion of Amyloid-β (Aβ) peptides has been considered for treating Alzheimer's disease. However, γ-secretase inhibitors suffer from severe side effects. As an alternative, γ-secretase modulators (GSM) reduce the generation of toxic peptides by enhancing the cleavage processivity without diminishing the enzyme activity. Starting from a known γ-secretase structure without substrate but in complex with an E2012 GSM, we generated a structural model that included a bound Aβ43 peptide and studied interactions among enzyme, substrate, GSM, and lipids. Our result suggests that E2012 binding at the enzyme-substrate-membrane interface attenuates the membrane distortion by shielding the substrate-membrane interaction. The model predicts that the E2012 modulation is charge-dependent and explains the preserved hydrogen acceptor and the aromatic ring observed in many imidazole-based GSM. Predicted effects of γ-secretase mutations on E2012 modulation were confirmed experimentally. We anticipate that the study will facilitate the future development of effective GSMs.
Collapse
Affiliation(s)
- Shu-Yu Chen
- Center for Functional Protein Assemblies, Garching 85748, Germany
| | - Matthias Koch
- VIB/KU Leuven, VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium
| | | | - Martin Zacharias
- Center for Functional Protein Assemblies, Garching 85748, Germany
| |
Collapse
|
4
|
Bammens L, Chávez-Gutiérrez L, Tolia A, Zwijsen A, De Strooper B. Withdrawal: Functional and topological analysis of Pen-2, the fourth subunit of the γ-secretase complex. J Biol Chem 2023; 299:104985. [PMID: 37413955 PMCID: PMC10404655 DOI: 10.1016/j.jbc.2023.104985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2023] Open
|
5
|
Chen SY, Feilen LP, Chávez-Gutiérrez L, Steiner H, Zacharias M. Enzyme-substrate hybrid β-sheet controls geometry and water access to the γ-secretase active site. Commun Biol 2023; 6:670. [PMID: 37355752 PMCID: PMC10290658 DOI: 10.1038/s42003-023-05039-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 06/12/2023] [Indexed: 06/26/2023] Open
Abstract
γ-Secretase is an aspartyl intramembrane protease that cleaves the amyloid precursor protein (APP) involved in Alzheimer's disease pathology and other transmembrane proteins. Substrate-bound structures reveal a stable hybrid β-sheet immediately following the substrate scissile bond consisting of β1 and β2 from the enzyme and β3 from the substrate. Molecular dynamics simulations and enhanced sampling simulations demonstrate that the hybrid β-sheet stability is strongly correlated with the formation of a stable cleavage-compatible active geometry and it also controls water access to the active site. The hybrid β-sheet is only stable for substrates with 3 or more C-terminal residues beyond the scissile bond. The simulation model allowed us to predict the effect of Pro and Phe mutations that weaken the formation of the hybrid β-sheet which were confirmed by experimental testing. Our study provides a direct explanation why γ-secretase preferentially cleaves APP in steps of 3 residues and how the hybrid β-sheet facilitates γ-secretase proteolysis.
Collapse
Affiliation(s)
- Shu-Yu Chen
- Center of Functional Protein Assemblies, Technical University of Munich, Garching, Germany
| | - Lukas P Feilen
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Harald Steiner
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
- Biomedical Center (BMC), Division of Metabolic Biochemistry, Faculty of Medicine, LMU Munich, Germany
| | - Martin Zacharias
- Center of Functional Protein Assemblies, Technical University of Munich, Garching, Germany.
| |
Collapse
|
6
|
Ringman JM, Dorrani N, Fernández SG, Signer R, Martinez-Agosto J, Lee H, Douine ED, Qiao Y, Shi Y, D’Orazio L, Pawar S, Robbie L, Kashani AH, Singer M, Byers JT, Magaki S, Guzman S, Sagare A, Zlokovic B, Cederbaum S, Nelson S, Sheikh-Bahaei N, Chui HC, Chávez-Gutiérrez L, Vinters HV. Characterization of spastic paraplegia in a family with a novel PSEN1 mutation. Brain Commun 2023; 5:fcad030. [PMID: 36895955 PMCID: PMC9991506 DOI: 10.1093/braincomms/fcad030] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 09/09/2022] [Accepted: 02/13/2023] [Indexed: 02/17/2023] Open
Abstract
Spastic paraparesis has been described to occur in 13.7% of PSEN1 mutations and can be the presenting feature in 7.5%. In this paper, we describe a family with a particularly young onset of spastic paraparesis due to a novel mutation in PSEN1 (F388S). Three affected brothers underwent comprehensive imaging protocols, two underwent ophthalmological evaluations and one underwent neuropathological examination after his death at age 29. Age of onset was consistently at age 23 with spastic paraparesis, dysarthria and bradyphrenia. Pseudobulbar affect followed with progressive gait problems leading to loss of ambulation in the late 20s. Cerebrospinal fluid levels of amyloid-β, tau and phosphorylated tau and florbetaben PET were consistent with Alzheimer's disease. Flortaucipir PET showed an uptake pattern atypical for Alzheimer's disease, with disproportionate signal in posterior brain areas. Diffusion tensor imaging showed decreased mean diffusivity in widespread areas of white matter but particularly in areas underlying the peri-Rolandic cortex and in the corticospinal tracts. These changes were more severe than those found in carriers of another PSEN1 mutation, which can cause spastic paraparesis at a later age (A431E), which were in turn more severe than among persons carrying autosomal dominant Alzheimer's disease mutations not causing spastic paraparesis. Neuropathological examination confirmed the presence of cotton wool plaques previously described in association with spastic parapresis and pallor and microgliosis in the corticospinal tract with severe amyloid-β pathology in motor cortex but without unequivocal disproportionate neuronal loss or tau pathology. In vitro modelling of the effects of the mutation demonstrated increased production of longer length amyloid-β peptides relative to shorter that predicted the young age of onset. In this paper, we provide imaging and neuropathological characterization of an extreme form of spastic paraparesis occurring in association with autosomal dominant Alzheimer's disease, demonstrating robust diffusion and pathological abnormalities in white matter. That the amyloid-β profiles produced predicted the young age of onset suggests an amyloid-driven aetiology though the link between this and the white matter pathology remains undefined.
Collapse
Affiliation(s)
- John M Ringman
- Department of Neurology, Keck School of Medicine at University of Southern California, Los Angeles, CA 90033, USA
| | | | - Sara Gutiérrez Fernández
- Department of Neurosciences, VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Leuven 3000, Belgium
| | - Rebecca Signer
- Department of Human Genetics, UCLA, Los Angeles, CA 90095, USA
| | | | - Hane Lee
- Department of Human Genetics, UCLA, Los Angeles, CA 90095, USA
- Department of Pathology and Laboratory Medicine, UCLA, Los Angeles, CA 90095, USA
| | - Emilie D Douine
- Department of Human Genetics, UCLA, Los Angeles, CA 90095, USA
| | - Yuchuan Qiao
- Department of Neurology, USC Stevens Neuroimaging and Informatics Institute, Los Angeles, CA 90033, USA
| | - Yonggang Shi
- Department of Neurology, USC Stevens Neuroimaging and Informatics Institute, Los Angeles, CA 90033, USA
| | - Lina D’Orazio
- Department of Neurology, Keck School of Medicine at University of Southern California, Los Angeles, CA 90033, USA
| | - Sanjay Pawar
- Department of Neurology, Keck School of Medicine at University of Southern California, Los Angeles, CA 90033, USA
| | - Leah Robbie
- Department of Neurology, Keck School of Medicine at University of Southern California, Los Angeles, CA 90033, USA
| | - Amir H Kashani
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD 21287, USA
| | - Maxwell Singer
- Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Joshua T Byers
- Section of Neuropathology, Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Shino Magaki
- Section of Neuropathology, Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Sam Guzman
- Department of Pathology, Keck School of Medicine at USC, Los Angeles, CA 90033, USA
| | - Abhay Sagare
- Zilkha Neurogenetics Institute, University of Southern California, Los Angeles, CA 90033, USA
| | - Berislav Zlokovic
- Zilkha Neurogenetics Institute, University of Southern California, Los Angeles, CA 90033, USA
| | - Stephen Cederbaum
- Department of Pediatrics, UCLA, Los Angeles, CA 90095, USA
- Department of Human Genetics, UCLA, Los Angeles, CA 90095, USA
| | - Stanley Nelson
- Department of Pediatrics, UCLA, Los Angeles, CA 90095, USA
- Department of Human Genetics, UCLA, Los Angeles, CA 90095, USA
- Department of Pathology and Laboratory Medicine, UCLA, Los Angeles, CA 90095, USA
| | - Nasim Sheikh-Bahaei
- Department of Radiology, University of Southern California, Los Angeles, CA 90033, USA
| | - Helena C Chui
- Department of Neurology, Keck School of Medicine at University of Southern California, Los Angeles, CA 90033, USA
| | - Lucía Chávez-Gutiérrez
- Department of Neurosciences, VIB-KU Leuven Center for Brain & Disease Research, Leuven 3000, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Leuven 3000, Belgium
| | - Harry V Vinters
- Section of Neuropathology, Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| |
Collapse
|
7
|
Petit D, Hitzenberger M, Koch M, Lismont S, Zoltowska KM, Enzlein T, Hopf C, Zacharias M, Chávez-Gutiérrez L. Enzyme-substrate interface targeting by imidazole-based γ-secretase modulators activates γ-secretase and stabilizes its interaction with APP. EMBO J 2022; 41:e111084. [PMID: 36121025 DOI: 10.15252/embj.2022111084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 03/04/2022] [Revised: 08/11/2022] [Accepted: 08/22/2022] [Indexed: 11/09/2022] Open
Abstract
Alzheimer's disease (AD) pathogenesis has been linked to the accumulation of longer, aggregation-prone amyloid β (Aβ) peptides in the brain. Γ-secretases generate Aβ peptides from the amyloid precursor protein (APP). Γ-secretase modulators (GSMs) promote the generation of shorter, less-amyloidogenic Aβs and have therapeutic potential. However, poorly defined drug-target interactions and mechanisms of action have hampered their therapeutic development. Here, we investigate the interactions between the imidazole-based GSM and its target γ-secretase-APP using experimental and in silico approaches. We map the GSM binding site to the enzyme-substrate interface, define a drug-binding mode that is consistent with functional and structural data, and provide molecular insights into the underlying mechanisms of action. In this respect, our analyses show that occupancy of a γ-secretase (sub)pocket, mediating binding of the modulator's imidazole moiety, is sufficient to trigger allosteric rearrangements in γ-secretase as well as stabilize enzyme-substrate interactions. Together, these findings may facilitate the rational design of new modulators of γ-secretase with improved pharmacological properties.
Collapse
Affiliation(s)
- Dieter Petit
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Manuel Hitzenberger
- Center for Functional Protein Assemblies, Theoretical Biophysics (T38), Technical University of Munich, Garching, Germany
| | - Matthias Koch
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Sam Lismont
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Katarzyna Marta Zoltowska
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Thomas Enzlein
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium.,Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Mannheim, Germany
| | - Carsten Hopf
- Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Mannheim, Germany.,Medical Faculty, Heidelberg University, Heidelberg, Germany
| | - Martin Zacharias
- Center for Functional Protein Assemblies, Theoretical Biophysics (T38), Technical University of Munich, Garching, Germany
| | - Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| |
Collapse
|
8
|
Petit D, Fernández SG, Zoltowska KM, Enzlein T, Ryan NS, O'Connor A, Szaruga M, Hill E, Vandenberghe R, Fox NC, Chávez-Gutiérrez L. Aβ profiles generated by Alzheimer's disease causing PSEN1 variants determine the pathogenicity of the mutation and predict age at disease onset. Mol Psychiatry 2022; 27:2821-2832. [PMID: 35365805 PMCID: PMC9156411 DOI: 10.1038/s41380-022-01518-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 02/23/2022] [Accepted: 03/03/2022] [Indexed: 02/05/2023]
Abstract
Familial Alzheimer's disease (FAD), caused by mutations in Presenilin (PSEN1/2) and Amyloid Precursor Protein (APP) genes, is associated with an early age at onset (AAO) of symptoms. AAO is relatively consistent within families and between carriers of the same mutations, but differs markedly between individuals carrying different mutations. Gaining a mechanistic understanding of why certain mutations manifest several decades earlier than others is extremely important in elucidating the foundations of pathogenesis and AAO. Pathogenic mutations affect the protease (PSEN/γ-secretase) and the substrate (APP) that generate amyloid β (Aβ) peptides. Altered Aβ metabolism has long been associated with AD pathogenesis, with absolute or relative increases in Aβ42 levels most commonly implicated in the disease development. However, analyses addressing the relationships between these Aβ42 increments and AAO are inconsistent. Here, we investigated this central aspect of AD pathophysiology via comprehensive analysis of 25 FAD-linked Aβ profiles. Hypothesis- and data-driven approaches demonstrate linear correlations between mutation-driven alterations in Aβ profiles and AAO. In addition, our studies show that the Aβ (37 + 38 + 40) / (42 + 43) ratio offers predictive value in the assessment of 'unclear' PSEN1 variants. Of note, the analysis of PSEN1 variants presenting additionally with spastic paraparesis, indicates that a different mechanism underlies the aetiology of this distinct clinical phenotype. This study thus delivers valuable assays for fundamental, clinical and genetic research as well as supports therapeutic interventions aimed at shifting Aβ profiles towards shorter Aβ peptides.
Collapse
Affiliation(s)
- Dieter Petit
- VIB-KU Leuven Center for Brain & Disease Research, Herestraat 49 box 602, 3000, Leuven, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Herestraat 49 box 602, 3000, Leuven, Belgium
| | - Sara Gutiérrez Fernández
- VIB-KU Leuven Center for Brain & Disease Research, Herestraat 49 box 602, 3000, Leuven, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Herestraat 49 box 602, 3000, Leuven, Belgium
| | - Katarzyna Marta Zoltowska
- VIB-KU Leuven Center for Brain & Disease Research, Herestraat 49 box 602, 3000, Leuven, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Herestraat 49 box 602, 3000, Leuven, Belgium
| | - Thomas Enzlein
- VIB-KU Leuven Center for Brain & Disease Research, Herestraat 49 box 602, 3000, Leuven, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Herestraat 49 box 602, 3000, Leuven, Belgium
- Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Paul-Wittsack Str. 10, 68163, Mannheim, Germany
| | - Natalie S Ryan
- UK Dementia Research Institute at UCL, Queen Square, WC1N 3BG, London, UK
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, WC1N 3BG, London, UK
| | - Antoinette O'Connor
- UK Dementia Research Institute at UCL, Queen Square, WC1N 3BG, London, UK
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, WC1N 3BG, London, UK
| | - Maria Szaruga
- VIB-KU Leuven Center for Brain & Disease Research, Herestraat 49 box 602, 3000, Leuven, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Herestraat 49 box 602, 3000, Leuven, Belgium
| | - Elizabeth Hill
- VIB-KU Leuven Center for Brain & Disease Research, Herestraat 49 box 602, 3000, Leuven, Belgium
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Herestraat 49 box 602, 3000, Leuven, Belgium
| | - Rik Vandenberghe
- Laboratory for Cognitive Neurology, Department of Neurosciences, KU Leuven, Herestraat 49 box 1027, 3000, Leuven, Belgium
- Neurology Department, University Hospitals Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Nick C Fox
- UK Dementia Research Institute at UCL, Queen Square, WC1N 3BG, London, UK
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, WC1N 3BG, London, UK
| | - Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, Herestraat 49 box 602, 3000, Leuven, Belgium.
- Department of Neurosciences, Leuven Brain Institute, KU Leuven, Herestraat 49 box 602, 3000, Leuven, Belgium.
| |
Collapse
|
9
|
O'Connor A, Pannee J, Poole T, Arber C, Portelius E, Swift IJ, Heslegrave AJ, Abel E, Willumsen N, Rice H, Weston PSJ, Ryan NS, Polke JM, Nicholas JM, Mead S, Wray S, Chávez-Gutiérrez L, Frost C, Blennow K, Zetterberg H, Fox NC. Plasma amyloid-β ratios in autosomal dominant Alzheimer's disease: the influence of genotype. Brain 2021; 144:2964-2970. [PMID: 33892504 PMCID: PMC8634092 DOI: 10.1093/brain/awab166] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 10/21/2020] [Revised: 03/22/2021] [Accepted: 04/02/2021] [Indexed: 11/14/2022] Open
Abstract
In-vitro studies of autosomal dominant Alzheimer's disease implicate longer amyloid-beta peptides in disease pathogenesis, however less is known about the behaviour of these mutations in-vivo. In this cross-sectional cohort study, we used liquid chromatography-tandem mass spectrometry to analyse 66 plasma samples from individuals who were at-risk of inheriting a mutation or were symptomatic. We tested for differences in amyloid-beta42:38, 42:40 and 38:40 ratios between presenilin1 and amyloid precursor protein carriers. We examined the relationship between plasma and in-vitro models of amyloid-beta processing and tested for associations with parental age at onset. 39 participants were mutation carriers (28 presenilin1 and 11 amyloid precursor protein). Age- and sex-adjusted models showed marked differences in plasma amyloid-beta between genotypes: higher amyloid-beta42:38 in presenilin1 versus amyloid precursor protein (p < 0.001) and non-carriers (p < 0.001); higher amyloid-beta38:40 in amyloid precursor protein versus presenilin1 (p < 0.001) and non-carriers (p < 0.001); while amyloid-beta42:40 was higher in both mutation groups compared to non-carriers (both p < 0.001). Amyloid-beta profiles were reasonably consistent in plasma and cell lines. Within presenilin1, models demonstrated associations between amyloid-beta42:38, 42:40 and 38:40 ratios and parental age at onset. In-vivo differences in amyloid-beta processing between presenilin1 and amyloid precursor protein carriers provide insights into disease pathophysiology, which can inform therapy development.
Collapse
Affiliation(s)
- Antoinette O'Connor
- Dementia Research Centre, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.,UK Dementia Research Institute at UCL, London, WC1E 6AU, UK
| | - Josef Pannee
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80 Mölndal, Sweden
| | - Teresa Poole
- Dementia Research Centre, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.,Department of Medical Statistics, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Charles Arber
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Erik Portelius
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80 Mölndal, Sweden
| | - Imogen J Swift
- UK Dementia Research Institute at UCL, London, WC1E 6AU, UK
| | | | - Emily Abel
- UK Dementia Research Institute at UCL, London, WC1E 6AU, UK
| | - Nanet Willumsen
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Helen Rice
- Dementia Research Centre, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.,UK Dementia Research Institute at UCL, London, WC1E 6AU, UK
| | - Philip S J Weston
- Dementia Research Centre, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Natalie S Ryan
- Dementia Research Centre, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.,UK Dementia Research Institute at UCL, London, WC1E 6AU, UK
| | - James M Polke
- Neurogenetics Laboratory, National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London WC1N 3BG, UK
| | - Jennifer M Nicholas
- Dementia Research Centre, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.,Department of Medical Statistics, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Simon Mead
- National Prion Clinic, National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London WC1N 3BG, UK.,MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London W1W 7FF, UK
| | - Selina Wray
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, 3000 Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, 3000 Leuven, Belgium
| | - Chris Frost
- Department of Medical Statistics, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80 Mölndal, Sweden
| | - Henrik Zetterberg
- UK Dementia Research Institute at UCL, London, WC1E 6AU, UK.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80 Mölndal, Sweden
| | - Nick C Fox
- Dementia Research Centre, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK.,UK Dementia Research Institute at UCL, London, WC1E 6AU, UK
| |
Collapse
|
10
|
Szaruga M, Munteanu B, Lismont S, Veugelen S, Horré K, Mercken M, Saido TC, Ryan NS, De Vos T, Savvides SN, Gallardo R, Schymkowitz J, Rousseau F, Fox NC, Hopf C, De Strooper B, Chávez-Gutiérrez L. Alzheimer's-causing mutations shift Aβ length by destabilizing γ-secretase-Aβn interactions. Cell 2021; 184:2257-2258. [PMID: 33861967 DOI: 10.1016/j.cell.2021.03.058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
11
|
Zoltowska KM, Chávez-Gutiérrez L. Exploring the origins of nucleation. eLife 2021; 10:67269. [PMID: 33688830 PMCID: PMC7946419 DOI: 10.7554/elife.67269] [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: 03/05/2021] [Accepted: 03/05/2021] [Indexed: 11/24/2022] Open
Abstract
An approach called deep mutational scanning is improving our understanding of amyloid beta aggregation.
Collapse
Affiliation(s)
| | - Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), Leuven, Belgium
| |
Collapse
|
12
|
Franco ML, García-Carpio I, Comaposada-Baró R, Escribano-Saiz JJ, Chávez-Gutiérrez L, Vilar M. TrkA-mediated endocytosis of p75-CTF prevents cholinergic neuron death upon γ-secretase inhibition. Life Sci Alliance 2021; 4:4/4/e202000844. [PMID: 33536237 PMCID: PMC7898468 DOI: 10.26508/lsa.202000844] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [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: 07/08/2020] [Revised: 01/11/2021] [Accepted: 01/11/2021] [Indexed: 12/13/2022] Open
Abstract
The findings shed light into the adverse effects of GSIs observed in the Alzheimer’s field and explain, at least in part, the unexpected worsening in cognition observed in the semagacestat Phase 3 trial. γ-secretase inhibitors (GSI) were developed to reduce the generation of Aβ peptide to find new Alzheimer’s disease treatments. Clinical trials on Alzheimer’s disease patients, however, showed several side effects that worsened the cognitive symptoms of the treated patients. The observed side effects were partially attributed to Notch signaling. However, the effect on other γ-secretase substrates, such as the p75 neurotrophin receptor (p75NTR) has not been studied in detail. p75NTR is highly expressed in the basal forebrain cholinergic neurons (BFCNs) during all life. Here, we show that GSI treatment induces the oligomerization of p75CTF leading to the cell death of BFCNs, and that this event is dependent on TrkA activity. The oligomerization of p75CTF requires an intact cholesterol recognition sequence (CRAC) and the constitutive binding of TRAF6, which activates the JNK and p38 pathways. Remarkably, TrkA rescues from cell death by a mechanism involving the endocytosis of p75CTF. These results suggest that the inhibition of γ-secretase activity in aged patients, where the expression of TrkA in the BFCNs is already reduced, could accelerate cholinergic dysfunction and promote neurodegeneration.
Collapse
Affiliation(s)
- María Luisa Franco
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València (IBV-CSIC), València, Spain
| | - Irmina García-Carpio
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València (IBV-CSIC), València, Spain
| | - Raquel Comaposada-Baró
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València (IBV-CSIC), València, Spain
| | - Juan J Escribano-Saiz
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València (IBV-CSIC), València, Spain
| | - Lucía Chávez-Gutiérrez
- Vlaams Instituut voor Biotechnologie Katholieke Universiteit (VIB-KU) Leuven Center for Brain and Disease, Leuven, Belgium
| | - Marçal Vilar
- Molecular Basis of Neurodegeneration Unit, Institute of Biomedicine of València (IBV-CSIC), València, Spain
| |
Collapse
|
13
|
Enzlein T, Cordes J, Munteanu B, Michno W, Serneels L, De Strooper B, Hanrieder J, Wolf I, Chávez-Gutiérrez L, Hopf C. Computational Analysis of Alzheimer Amyloid Plaque Composition in 2D- and Elastically Reconstructed 3D-MALDI MS Images. Anal Chem 2020; 92:14484-14493. [PMID: 33138378 DOI: 10.1021/acs.analchem.0c02585] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
MALDI mass spectrometry imaging (MSI) enables label-free, spatially resolved analysis of a wide range of analytes in tissue sections. Quantitative analysis of MSI datasets is typically performed on single pixels or manually assigned regions of interest (ROIs). However, many sparse, small objects such as Alzheimer's disease (AD) brain deposits of amyloid peptides called plaques are neither single pixels nor ROIs. Here, we propose a new approach to facilitate the comparative computational evaluation of amyloid plaque-like objects by MSI: a fast PLAQUE PICKER tool that enables a statistical evaluation of heterogeneous amyloid peptide composition. Comparing two AD mouse models, APP NL-G-F and APP PS1, we identified distinct heterogeneous plaque populations in the NL-G-F model but only one class of plaques in the PS1 model. We propose quantitative metrics for the comparison of technical and biological MSI replicates. Furthermore, we reconstructed a high-accuracy 3D-model of amyloid plaques in a fully automated fashion, employing rigid and elastic MSI image registration using structured and plaque-unrelated reference ion images. Statistical single-plaque analysis in reconstructed 3D-MSI objects revealed the Aβ1-42Arc peptide to be located either in the core of larger plaques or in small plaques without colocalization of other Aβ isoforms. In 3D, a substantially larger number of small plaques were observed than that indicated by the 2D-MSI data, suggesting that quantitative analysis of molecularly diverse sparsely-distributed features may benefit from 3D-reconstruction. Data are available via ProteomeXchange with identifier PXD020824.
Collapse
Affiliation(s)
- Thomas Enzlein
- Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Paul-Wittsack Str. 10, Mannheim 68163, Germany.,KU Leuven-VIB Center for Brain & Disease Research, VIB, Leuven 3000, Belgium.,Department of Neurosciences, Leuven Institute for Neuroscience and Disease, KU Leuven, Leuven 3000, Belgium
| | - Jonas Cordes
- Faculty of Computer Science, University of Applied Sciences Mannheim, Paul-Wittsack-Straße 10, Mannheim 68163, Germany
| | - Bogdan Munteanu
- Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Paul-Wittsack Str. 10, Mannheim 68163, Germany
| | - Wojciech Michno
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, Mölndal Hospital, House V3, Mölndal 43180, Sweden.,Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Lutgarde Serneels
- KU Leuven-VIB Center for Brain & Disease Research, VIB, Leuven 3000, Belgium.,Department of Neurosciences, Leuven Institute for Neuroscience and Disease, KU Leuven, Leuven 3000, Belgium
| | - Bart De Strooper
- KU Leuven-VIB Center for Brain & Disease Research, VIB, Leuven 3000, Belgium.,Department of Neurosciences, Leuven Institute for Neuroscience and Disease, KU Leuven, Leuven 3000, Belgium.,UK Dementia Research Institute at UCL, University College London, London WC1E 6BT U.K
| | - Jörg Hanrieder
- Department of Psychiatry and Neurochemistry, Sahlgrenska Academy at the University of Gothenburg, Mölndal Hospital, House V3, Mölndal 43180, Sweden.,Department of Neurodegenerative Diseases, University College London Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, United Kingdom
| | - Ivo Wolf
- Faculty of Computer Science, University of Applied Sciences Mannheim, Paul-Wittsack-Straße 10, Mannheim 68163, Germany
| | - Lucía Chávez-Gutiérrez
- KU Leuven-VIB Center for Brain & Disease Research, VIB, Leuven 3000, Belgium.,Department of Neurosciences, Leuven Institute for Neuroscience and Disease, KU Leuven, Leuven 3000, Belgium
| | - Carsten Hopf
- Center for Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Paul-Wittsack Str. 10, Mannheim 68163, Germany
| |
Collapse
|
14
|
Chávez-Gutiérrez L, Szaruga M. Mechanisms of neurodegeneration - Insights from familial Alzheimer's disease. Semin Cell Dev Biol 2020; 105:75-85. [PMID: 32418657 DOI: 10.1016/j.semcdb.2020.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [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: 10/17/2019] [Revised: 03/13/2020] [Accepted: 03/16/2020] [Indexed: 12/18/2022]
Abstract
The rising prevalence of Alzheimer's disease (AD), together with the lack of effective treatments, portray it as one of the major health challenges of our times. Untangling AD implies advancing the knowledge of the biology that gets disrupted during the disease while deciphering the molecular and cellular mechanisms leading to AD-related neurodegeneration. In fact, a solid mechanistic understanding of the disease processes stands as an essential prerequisite for the development of safe and effective treatments. Genetics has provided invaluable clues to the genesis of the disease by revealing deterministic genes - Presenilins (PSENs) and the Amyloid Precursor Protein (APP) - that, when affected, lead in an autosomal dominant manner to early-onset, familial AD (FAD). PSEN is the catalytic subunit of the membrane-embedded γ-secretase complexes, which act as proteolytic switches regulating key cell signalling cascades. Importantly, these intramembrane proteases are responsible for the production of Amyloid β (Aβ) peptides from APP. The convergence of pathogenic mutations on one functional pathway, the amyloidogenic cleavage of APP, strongly supports the significance of this process in AD pathogenesis. Here, we review and discuss the state-of-the-art knowledge of the molecular mechanisms underlying FAD, their implications for the sporadic form of the disease and for the development of safe AD therapeutics.
Collapse
Affiliation(s)
- Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium; Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium.
| | - Maria Szaruga
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium; Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| |
Collapse
|
15
|
Santos-Mandujano RA, Ryan NS, Chávez-Gutiérrez L, Sánchez-Torres C, Meraz-Ríos MA. Clinical Association of White Matter Hyperintensities Localization in a Mexican Family with Spastic Paraparesis Carrying the PSEN1 A431E Mutation. J Alzheimers Dis 2020; 73:1075-1083. [DOI: 10.3233/jad-190978] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | - Natalie S. Ryan
- Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Institute of Neurology, London, UK
| | - Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Carmen Sánchez-Torres
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV), CDMX, México
| | - Marco Antonio Meraz-Ríos
- Department of Molecular Biomedicine, Center for Research and Advanced Studies (CINVESTAV), CDMX, México
| |
Collapse
|
16
|
Petit D, Hitzenberger M, Lismont S, Zoltowska KM, Ryan NS, Mercken M, Bischoff F, Zacharias M, Chávez-Gutiérrez L. Extracellular interface between APP and Nicastrin regulates Aβ length and response to γ-secretase modulators. EMBO J 2019; 38:embj.2019101494. [PMID: 31109937 PMCID: PMC6576158 DOI: 10.15252/embj.2019101494] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [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: 01/06/2019] [Revised: 04/02/2019] [Accepted: 04/11/2019] [Indexed: 12/20/2022] Open
Abstract
γ-Secretase complexes (GSECs) are multimeric membrane proteases involved in a variety of physiological processes and linked to Alzheimer's disease (AD). Presenilin (PSEN, catalytic subunit), Nicastrin (NCT), Presenilin Enhancer 2 (PEN-2), and Anterior Pharynx Defective 1 (APH1) are the essential subunits of GSECs. Mutations in PSEN and the Amyloid Precursor Protein (APP) cause early-onset AD GSECs successively cut APP to generate amyloid-β (Aβ) peptides of various lengths. AD-causing mutations destabilize GSEC-APP/Aβn interactions and thus enhance the production of longer Aβs, which elicit neurotoxic events underlying pathogenesis. Here, we investigated the molecular strategies that anchor GSEC and APP/Aβn during the sequential proteolysis. Our studies reveal that a direct interaction between NCT ectodomain and APPC99 influences the stability of GSEC-Aβn assemblies and thereby modulates Aβ length. The data suggest a potential link between single-nucleotide variants in NCSTN and AD risk. Furthermore, our work indicates that an extracellular interface between the protease (NCT, PSEN) and the substrate (APP) represents the target for compounds (GSMs) modulating Aβ length. Our findings may guide future rationale-based drug discovery efforts.
Collapse
Affiliation(s)
- Dieter Petit
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Manuel Hitzenberger
- Physics Department, Theoretical Biophysics (T38), Technical University of Munich, München, Germany
| | - Sam Lismont
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Katarzyna Marta Zoltowska
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| | - Natalie S Ryan
- Dementia Research Centre, Department of Neurodegenerative Disease UCL Queen Square Institute of Neurology, London, UK
| | - Marc Mercken
- Janssen Research & Development, Division of Janssen Pharmaceutica NV, Beerse, Belgium.,Janssen Research & Development, Neuroscience biology Turnhoutseweg, Beerse, Belgium
| | - François Bischoff
- Janssen Research & Development, Division of Janssen Pharmaceutica NV, Beerse, Belgium
| | - Martin Zacharias
- Physics Department, Theoretical Biophysics (T38), Technical University of Munich, München, Germany
| | - Lucía Chávez-Gutiérrez
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium .,Department of Neurosciences, Leuven Research Institute for Neuroscience and Disease (LIND), KU Leuven, Leuven, Belgium
| |
Collapse
|
17
|
Acx H, Serneels L, Radaelli E, Muyldermans S, Vincke C, Pepermans E, Müller U, Chávez-Gutiérrez L, De Strooper B. Inactivation of γ-secretases leads to accumulation of substrates and non-Alzheimer neurodegeneration. EMBO Mol Med 2018; 9:1088-1099. [PMID: 28588032 PMCID: PMC5538297 DOI: 10.15252/emmm.201707561] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [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] [Indexed: 11/09/2022] Open
Abstract
γ-Secretases are a family of intramembrane cleaving aspartyl proteases and important drug targets in Alzheimer's disease. Here, we generated mice deficient for all γ-secretases in the pyramidal neurons of the postnatal forebrain by deleting the three anterior pharynx defective 1 (Aph1) subunits (Aph1abc cKO Cre+). The mice show progressive cortical atrophy, neuronal loss, and gliosis. Interestingly, this is associated with more than 10-fold accumulation of membrane-bound fragments of App, Aplp1, Nrg1, and Dcc, while other known substrates of γ-secretase such as Aplp2, Lrp1, and Sdc3 accumulate to lesser extents. Despite numerous reports linking neurodegeneration to accumulation of membrane-bound App fragments, deletion of App expression in the combined Aph1 knockout does not rescue this phenotype. Importantly, knockout of only Aph1a- or Aph1bc-secretases causes limited and differential accumulation of substrates. This was not associated with neurodegeneration. Further development of selective Aph1-γ-secretase inhibitors should be considered for treatment of Alzheimer's disease.
Collapse
Affiliation(s)
- Hermien Acx
- VIB Center for Brain and Disease Research, Leuven, Belgium.,KU Leuven Department for Neurosciences, Leuven Institute for Neurodegenerative Disorders (LIND) and Universitaire Ziekenhuizen Leuven, University of Leuven, Leuven, Belgium
| | - Lutgarde Serneels
- VIB Center for Brain and Disease Research, Leuven, Belgium.,KU Leuven Department for Neurosciences, Leuven Institute for Neurodegenerative Disorders (LIND) and Universitaire Ziekenhuizen Leuven, University of Leuven, Leuven, Belgium
| | - Enrico Radaelli
- VIB Center for Brain and Disease Research, Leuven, Belgium.,KU Leuven Department for Neurosciences, Leuven Institute for Neurodegenerative Disorders (LIND) and Universitaire Ziekenhuizen Leuven, University of Leuven, Leuven, Belgium
| | - Serge Muyldermans
- Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Cécile Vincke
- Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Elise Pepermans
- VIB Center for Brain and Disease Research, Leuven, Belgium.,KU Leuven Department for Neurosciences, Leuven Institute for Neurodegenerative Disorders (LIND) and Universitaire Ziekenhuizen Leuven, University of Leuven, Leuven, Belgium
| | - Ulrike Müller
- Institute for Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, Heidelberg, Germany
| | - Lucía Chávez-Gutiérrez
- VIB Center for Brain and Disease Research, Leuven, Belgium .,KU Leuven Department for Neurosciences, Leuven Institute for Neurodegenerative Disorders (LIND) and Universitaire Ziekenhuizen Leuven, University of Leuven, Leuven, Belgium
| | - Bart De Strooper
- VIB Center for Brain and Disease Research, Leuven, Belgium .,KU Leuven Department for Neurosciences, Leuven Institute for Neurodegenerative Disorders (LIND) and Universitaire Ziekenhuizen Leuven, University of Leuven, Leuven, Belgium.,UCL Dementia Research Institute (DRI-UK), London, UK
| |
Collapse
|
18
|
Voytyuk I, De Strooper B, Chávez-Gutiérrez L. Modulation of γ- and β-Secretases as Early Prevention Against Alzheimer's Disease. Biol Psychiatry 2018; 83:320-327. [PMID: 28918941 DOI: 10.1016/j.biopsych.2017.08.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 08/01/2017] [Accepted: 08/03/2017] [Indexed: 01/18/2023]
Abstract
The genetic evidence implicating amyloid-β in the initial stage of Alzheimer's disease is unequivocal. However, the long biochemical and cellular prodromal phases of the disease suggest that dementia is the result of a series of molecular and cellular cascades whose nature and connections remain unknown. Therefore, it is unlikely that treatments directed at amyloid-β will have major clinical effects in the later stages of the disease. We discuss the two major candidate therapeutic targets to lower amyloid-β in a preventive mode, i.e., γ- and β-secretase; the rationale behind these two targets; and the current state of the field.
Collapse
Affiliation(s)
- Iryna Voytyuk
- KU Leuven Department for Neurosciences, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Bart De Strooper
- KU Leuven Department for Neurosciences, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; UK Dementia Research Institute, University College, London, United Kingdom.
| | - Lucía Chávez-Gutiérrez
- KU Leuven Department for Neurosciences, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| |
Collapse
|
19
|
Veugelen S, Saito T, Saido TC, Chávez-Gutiérrez L, De Strooper B. Familial Alzheimer's Disease Mutations in Presenilin Generate Amyloidogenic Aβ Peptide Seeds. Neuron 2017; 90:410-6. [PMID: 27100199 DOI: 10.1016/j.neuron.2016.03.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 12/24/2015] [Accepted: 03/10/2016] [Indexed: 01/15/2023]
Abstract
Recently it was proposed that the familial Alzheimer's disease (FAD) causing presenilin (PSEN) mutations PSEN1-L435F and PSEN1-C410Y do not support the generation of Aβ-peptides from the amyloid precursor protein (APP). This challenges the amyloid hypothesis and disagrees with previous work showing that PSEN1 FAD causing mutations generate invariably long Aβ and seed amyloid. We contrast here the proteolytic activities of these mutant PSEN alleles with the complete loss-of-function PSEN1-D257A allele. We find residual carboxy- and endo-peptidase γ-secretase activities, similar to the formerly characterized PSEN1-R278I. We conclude that the PSEN1-L435F and -C410Y mutations are extreme examples of the previously proposed "dysfunction" of γ-secretase that characterizes FAD-associated PSEN. This Matters Arising paper is in response to Xia et al. (2015), published in Neuron. See also the response by Xia et al. (2016), published in this issue.
Collapse
Affiliation(s)
- Sarah Veugelen
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium; Center for Human Genetics, and Leuven Institute for Neurodegenerative Diseases (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Lucía Chávez-Gutiérrez
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium; Center for Human Genetics, and Leuven Institute for Neurodegenerative Diseases (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium.
| | - Bart De Strooper
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium; Center for Human Genetics, and Leuven Institute for Neurodegenerative Diseases (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium; Institute of Neurology, University College London, London, WC1N 3BG, UK.
| |
Collapse
|
20
|
Schoonaert L, Rué L, Roucourt B, Timmers M, Little S, Chávez-Gutiérrez L, Dewilde M, Joyce P, Curnock A, Weber P, Haustraete J, Hassanzadeh-Ghassabeh G, De Strooper B, Van Den Bosch L, Van Damme P, Lemmens R, Robberecht W. Identification and characterization of Nanobodies targeting the EphA4 receptor. J Biol Chem 2017; 292:11452-11465. [PMID: 28526745 PMCID: PMC5500810 DOI: 10.1074/jbc.m116.774141] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [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: 01/03/2017] [Revised: 05/16/2017] [Indexed: 12/14/2022] Open
Abstract
The ephrin receptor A4 (EphA4) is one of the receptors in the ephrin system that plays a pivotal role in a variety of cell-cell interactions, mostly studied during development. In addition, EphA4 has been found to play a role in cancer biology as well as in the pathogenesis of several neurological disorders such as stroke, spinal cord injury, multiple sclerosis, amyotrophic lateral sclerosis (ALS), and Alzheimer's disease. Pharmacological blocking of EphA4 has been suggested to be a therapeutic strategy for these disorders. Therefore, the aim of our study was to generate potent and selective Nanobodies against the ligand-binding domain of the human EphA4 receptor. We identified two Nanobodies, Nb 39 and Nb 53, that bind EphA4 with affinities in the nanomolar range. These Nanobodies were most selective for EphA4, with residual binding to EphA7 only. Using Alphascreen technology, we found that both Nanobodies displaced all known EphA4-binding ephrins from the receptor. Furthermore, Nb 39 and Nb 53 inhibited ephrin-induced phosphorylation of the EphA4 protein in a cell-based assay. Finally, in a cortical neuron primary culture, both Nanobodies were able to inhibit endogenous EphA4-mediated growth-cone collapse induced by ephrin-B3. Our results demonstrate the potential of Nanobodies to target the ligand-binding domain of EphA4. These Nanobodies may deserve further evaluation as potential therapeutics in disorders in which EphA4-mediated signaling plays a role.
Collapse
Affiliation(s)
- Lies Schoonaert
- From the KU Leuven-University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium.,VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium
| | - Laura Rué
- From the KU Leuven-University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium.,VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium
| | - Bart Roucourt
- KU Leuven-University of Leuven, Laboratory for Signal Integration in Cell Fate Decision, 3000 Leuven, Belgium
| | - Mieke Timmers
- From the KU Leuven-University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium.,VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium
| | - Susan Little
- Vertex Pharmaceuticals (Europe) Ltd., Biology Department, OX14 4RW Abingdon, United Kingdom
| | - Lucía Chávez-Gutiérrez
- VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium.,KU Leuven, Department of Neurosciences and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
| | - Maarten Dewilde
- VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium.,KU Leuven, Department of Neurosciences and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
| | - Peter Joyce
- Vertex Pharmaceuticals (Europe) Ltd., Biology Department, OX14 4RW Abingdon, United Kingdom
| | - Adam Curnock
- Vertex Pharmaceuticals (Europe) Ltd., Biology Department, OX14 4RW Abingdon, United Kingdom
| | - Peter Weber
- Vertex Pharmaceuticals (Europe) Ltd., Biology Department, OX14 4RW Abingdon, United Kingdom
| | - Jurgen Haustraete
- Protein Service Facility, Inflammation Research Center, VIB, Ghent University, 9052 Ghent, Belgium
| | | | - Bart De Strooper
- VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium.,KU Leuven, Department of Neurosciences and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium.,Institute of Neurology, University College London, WC1E 6BT London, United Kingdom, and
| | - Ludo Van Den Bosch
- From the KU Leuven-University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium.,VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium
| | - Philip Van Damme
- From the KU Leuven-University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium.,VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium.,University Hospitals Leuven, Department of Neurology, 3000 Leuven, Belgium
| | - Robin Lemmens
- From the KU Leuven-University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium.,VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, 3000 Leuven, Belgium.,University Hospitals Leuven, Department of Neurology, 3000 Leuven, Belgium
| | - Wim Robberecht
- From the KU Leuven-University of Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium, .,University Hospitals Leuven, Department of Neurology, 3000 Leuven, Belgium
| |
Collapse
|
21
|
Le Guennec K, Veugelen S, Quenez O, Szaruga M, Rousseau S, Nicolas G, Wallon D, Fluchere F, Frébourg T, De Strooper B, Campion D, Chávez-Gutiérrez L, Rovelet-Lecrux A. Deletion of exons 9 and 10 of the Presenilin 1 gene in a patient with Early-onset Alzheimer Disease generates longer amyloid seeds. Neurobiol Dis 2017; 104:97-103. [PMID: 28461250 DOI: 10.1016/j.nbd.2017.04.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 03/27/2017] [Accepted: 04/27/2017] [Indexed: 11/18/2022] Open
Abstract
Presenilin 1 (PSEN1) mutations are the main cause of autosomal dominant Early-onset Alzheimer Disease (EOAD). Among them, deletions of exon 9 have been reported to be associated with a phenotype of spastic paraparesis. Using exome data from a large sample of 522 EOAD cases and 584 controls to search for genomic copy-number variations (CNVs), we report here a novel partial, in-frame deletion of PSEN1, removing both exons 9 and 10. The patient presented with memory impairment associated with spastic paraparesis, both starting from the age of 56years. He presented a positive family history of EOAD. We performed functional analysis to elucidate the impact of this novel deletion on PSEN1 activity as part of the γ-secretase complex. The deletion does not affect the assembly of a mature protease complex but has an extreme impact on its global endopeptidase activity. The mutant carboxypeptidase-like activity is also strongly impaired and the deleterious mutant effect leads to an incomplete digestion of long Aβ peptides and enhances the production of Aβ43, which has been shown to be potently amyloidogenic and neurotoxic in vivo.
Collapse
Affiliation(s)
- Kilan Le Guennec
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Genetics and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France
| | - Sarah Veugelen
- VIB - Center for Brain and Disease Research, University of Leuven, 3000 Leuven, Belgium; Center for Human Genetics, Leuven Research Institute for Neuroscience & Disease (LIND), University of Leuven, 3000 Leuven, Belgium
| | - Olivier Quenez
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Genetics and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France
| | - Maria Szaruga
- VIB - Center for Brain and Disease Research, University of Leuven, 3000 Leuven, Belgium; Center for Human Genetics, Leuven Research Institute for Neuroscience & Disease (LIND), University of Leuven, 3000 Leuven, Belgium
| | - Stéphane Rousseau
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Genetics and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France
| | - Gaël Nicolas
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Genetics and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France
| | - David Wallon
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Neurology and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France
| | - Frédérique Fluchere
- Department of Neurology and Movement Disorders, APHM, La Timone, Pôle de Neurosciences cliniques, Aix-Marseille Univ, Marseille, France
| | - Thierry Frébourg
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Genetics, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France
| | - Bart De Strooper
- VIB - Center for Brain and Disease Research, University of Leuven, 3000 Leuven, Belgium; Center for Human Genetics, Leuven Research Institute for Neuroscience & Disease (LIND), University of Leuven, 3000 Leuven, Belgium; Institute of Neurology, University College London, Queen Square, WC1N 3BG London, UK
| | - Dominique Campion
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Genetics and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France; Department of Research, Rouvray Psychiatric Hospital, Sotteville-lès-Rouen, France
| | - Lucía Chávez-Gutiérrez
- VIB - Center for Brain and Disease Research, University of Leuven, 3000 Leuven, Belgium; Center for Human Genetics, Leuven Research Institute for Neuroscience & Disease (LIND), University of Leuven, 3000 Leuven, Belgium
| | - Anne Rovelet-Lecrux
- Normandie Univ, UNIROUEN, Inserm U1245, Rouen University Hospital, Department of Genetics and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, F 76000 Rouen, France.
| |
Collapse
|
22
|
Veugelen S, Dewilde M, De Strooper B, Chávez-Gutiérrez L. Screening and Characterization Strategies for Nanobodies Targeting Membrane Proteins. Methods Enzymol 2016; 584:59-97. [PMID: 28065273 DOI: 10.1016/bs.mie.2016.10.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
The study of membrane protein function and structure requires their successful detection, expression, solubilization, and/or reconstitution, which poses a challenging task and relies on the availability of suitable tools. Several research groups have successfully applied Nanobodies in the purification, as well as the functional and structural characterization of membrane proteins. Nanobodies are small, single-chain antibody fragments originating from camelids presenting on average a longer CDR3 which enables them to bind in cavities and clefts (such as active and allosteric sites). Notably, Nanobodies generally bind conformational epitopes making them very interesting tools to stabilize, dissect, and characterize specific protein conformations. In the clinic, several Nanobodies are under evaluation either as potential drug candidates or as diagnostic tools. In recent years, we have successfully generated high-affinity, conformation-sensitive anti-γ-secretase Nanobodies. γ-Secretase is a multimeric membrane protease involved in processing of the amyloid precursor protein with high clinical relevance as mutations in its catalytic subunit (Presenilin) cause early-onset Alzheimer's disease. Advancing our knowledge on the mechanisms governing γ-secretase intramembrane proteolysis through various strategies may lead to novel therapeutic avenues for Alzheimer's disease. In this chapter, we present the strategies we have developed and applied for the screening and characterization of anti-γ-secretase Nanobodies. These protocols could be of help in the generation of Nanobodies targeting other membrane proteins.
Collapse
Affiliation(s)
- S Veugelen
- University of Leuven, Leuven, Belgium; VIB Center for Brain and Disease, Leuven, Belgium
| | - M Dewilde
- University of Leuven, Leuven, Belgium; VIB Center for Brain and Disease, Leuven, Belgium
| | - B De Strooper
- University of Leuven, Leuven, Belgium; VIB Center for Brain and Disease, Leuven, Belgium; UCL Institute of Neurology, London, United Kingdom
| | - L Chávez-Gutiérrez
- University of Leuven, Leuven, Belgium; VIB Center for Brain and Disease, Leuven, Belgium.
| |
Collapse
|
23
|
Affiliation(s)
- Lucía Chávez-Gutiérrez
- VIB Center for the Biology of Disease, VIB-Leuven, Leuven, Belgium Center for Human Genetics, Universitaire Ziekenhuizen and LIND, KU Leuven, Leuven, Belgium
| | - Bart De Strooper
- VIB Center for the Biology of Disease, VIB-Leuven, Leuven, Belgium Center for Human Genetics, Universitaire Ziekenhuizen and LIND, KU Leuven, Leuven, Belgium Institute of Neurology, University College London, London, UK
| |
Collapse
|
24
|
Elad N, De Strooper B, Lismont S, Hagen W, Veugelen S, Arimon M, Horré K, Berezovska O, Sachse C, Chávez-Gutiérrez L. The dynamic conformational landscape of gamma-secretase. J Cell Sci 2016; 128:589-98. [PMID: 25501811 PMCID: PMC4311135 DOI: 10.1242/jcs.164384] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The structure and function of the gamma-secretase proteases are of great interest because of their crucial roles in cellular and disease processes. We established a novel purification protocol for the gamma-secretase complex that involves a conformation- and complex-specific nanobody, yielding highly pure and active enzyme. Using single particle electron microscopy, we analyzed the gamma-secretase structure and its conformational variability. Under steady-state conditions, the complex adopts three major conformations, which differ in overall compactness and relative position of the nicastrin ectodomain. Occupancy of the active or substrate-binding sites by inhibitors differentially stabilizes subpopulations of particles with compact conformations, whereas a mutation linked to familial Alzheimer disease results in enrichment of extended-conformation complexes with increased flexibility. Our study presents the csecretase complex as a dynamic population of interconverting conformations, involving rearrangements at the nanometer scale and a high level of structural interdependence between subunits. The fact that protease inhibition or clinical mutations, which affect amyloid beta (Abeta) generation, enrich for particular subpopulations of conformers indicates the functional relevance of the observed dynamic changes, which are likely to be instrumental for highly allosteric behavior of the enzyme.
Collapse
Affiliation(s)
- Nadav Elad
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium
- Center of Human Genetics, University Hospitals Leuven & Department of Human Genetics, KU Leuven, and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
| | - Bart De Strooper
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium
- Center of Human Genetics, University Hospitals Leuven & Department of Human Genetics, KU Leuven, and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
- UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
- Authors for correspondence (; ; )
| | - Sam Lismont
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium
- Center of Human Genetics, University Hospitals Leuven & Department of Human Genetics, KU Leuven, and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
| | - Wim Hagen
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstrasse1, 69117 Heidelberg, Germany
| | - Sarah Veugelen
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium
- Center of Human Genetics, University Hospitals Leuven & Department of Human Genetics, KU Leuven, and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
| | - Muriel Arimon
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Katrien Horré
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium
- Center of Human Genetics, University Hospitals Leuven & Department of Human Genetics, KU Leuven, and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
| | - Oksana Berezovska
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstrasse1, 69117 Heidelberg, Germany
| | - Carsten Sachse
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstrasse1, 69117 Heidelberg, Germany
- Authors for correspondence (; ; )
| | - Lucía Chávez-Gutiérrez
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium
- Center of Human Genetics, University Hospitals Leuven & Department of Human Genetics, KU Leuven, and Leuven Research Institute for Neuroscience and Disease (LIND), 3000 Leuven, Belgium
- Authors for correspondence (; ; )
| |
Collapse
|
25
|
Szaruga M, Veugelen S, Benurwar M, Lismont S, Sepulveda-Falla D, Lleo A, Ryan NS, Lashley T, Fox NC, Murayama S, Gijsen H, De Strooper B, Chávez-Gutiérrez L. Qualitative changes in human γ-secretase underlie familial Alzheimer's disease. J Exp Med 2015; 212:2003-13. [PMID: 26481686 PMCID: PMC4647268 DOI: 10.1084/jem.20150892] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [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: 05/28/2015] [Accepted: 09/11/2015] [Indexed: 12/02/2022] Open
Abstract
Mutations in the catalytic subunit of the γ-secretase complex, Presenilin, cause familial Alzheimer’s disease. Analysis of patients’ brains shows that these mutations do not result in loss of enzymatic function but in qualitative changes in Aβ product profiles. Presenilin (PSEN) pathogenic mutations cause familial Alzheimer’s disease (AD [FAD]) in an autosomal-dominant manner. The extent to which the healthy and diseased alleles influence each other to cause neurodegeneration remains unclear. In this study, we assessed γ-secretase activity in brain samples from 15 nondemented subjects, 22 FAD patients harboring nine different mutations in PSEN1, and 11 sporadic AD (SAD) patients. FAD and control brain samples had similar overall γ-secretase activity levels, and therefore, loss of overall (endopeptidase) γ-secretase function cannot be an essential part of the pathogenic mechanism. In contrast, impaired carboxypeptidase-like activity (γ-secretase dysfunction) is a constant feature in all FAD brains. Significantly, we demonstrate that pharmacological activation of the carboxypeptidase-like γ-secretase activity with γ-secretase modulators alleviates the mutant PSEN pathogenic effects. Most SAD cases display normal endo- and carboxypeptidase-like γ-secretase activities. However and interestingly, a few SAD patient samples display γ-secretase dysfunction, suggesting that γ-secretase may play a role in some SAD cases. In conclusion, our study highlights qualitative shifts in amyloid-β (Aβ) profiles as the common denominator in FAD and supports a model in which the healthy allele contributes with normal Aβ products and the diseased allele generates longer aggregation-prone peptides that act as seeds inducing toxic amyloid conformations.
Collapse
Affiliation(s)
- Maria Szaruga
- VIB Center for the Biology of Disease, University of Leuven (KU Leuven), 3000 Leuven, Belgium Center for Human Genetics (CME) and Leuven Research Institute for Neuroscience and Disease (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium
| | - Sarah Veugelen
- VIB Center for the Biology of Disease, University of Leuven (KU Leuven), 3000 Leuven, Belgium Center for Human Genetics (CME) and Leuven Research Institute for Neuroscience and Disease (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium
| | - Manasi Benurwar
- VIB Center for the Biology of Disease, University of Leuven (KU Leuven), 3000 Leuven, Belgium Center for Human Genetics (CME) and Leuven Research Institute for Neuroscience and Disease (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium
| | - Sam Lismont
- VIB Center for the Biology of Disease, University of Leuven (KU Leuven), 3000 Leuven, Belgium Center for Human Genetics (CME) and Leuven Research Institute for Neuroscience and Disease (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium
| | - Diego Sepulveda-Falla
- Institut für Neuropathologie, Universitätsklinikum Hamburg-Eppendorf, 20246 Hamburg, Germany Neuroscience Group of Antioquia, Faculty of Medicine, University of Antioquia, Medellín 1226, Colombia
| | - Alberto Lleo
- Unidad de Memoria, Departamento de Neurología, Institut d'Investigacions Biomèdiques Sant Pau, Hospital de Sant Pau, 08025 Barcelona, Spain Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas (CIBERNED), 28049 Madrid, Spain
| | - Natalie S Ryan
- Dementia Research Centre, Institute of Neurology, University College London, London WC1N 3AR, England, UK
| | - Tammaryn Lashley
- Queen Square Brain Bank for Neurological Disorders, Department of Molecular Neuroscience, Institute of Neurology, University College London, London WC1N 3AR, England, UK
| | - Nick C Fox
- Dementia Research Centre, Institute of Neurology, University College London, London WC1N 3AR, England, UK
| | - Shigeo Murayama
- Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo 173-0015, Japan
| | - Harrie Gijsen
- Janssen Research and Development Division, Janssen Pharmaceutica NV, 2340 Beerse, Belgium
| | - Bart De Strooper
- VIB Center for the Biology of Disease, University of Leuven (KU Leuven), 3000 Leuven, Belgium Center for Human Genetics (CME) and Leuven Research Institute for Neuroscience and Disease (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium Department of Molecular Neuroscience, Institute of Neurology, University College London, London WC1N 3AR, England, UK
| | - Lucía Chávez-Gutiérrez
- VIB Center for the Biology of Disease, University of Leuven (KU Leuven), 3000 Leuven, Belgium Center for Human Genetics (CME) and Leuven Research Institute for Neuroscience and Disease (LIND), University of Leuven (KU Leuven), 3000 Leuven, Belgium
| |
Collapse
|
26
|
Acx H, Chávez-Gutiérrez L, Serneels L, Lismont S, Benurwar M, Elad N, De Strooper B. Signature amyloid β profiles are produced by different γ-secretase complexes. J Biol Chem 2013; 289:4346-55. [PMID: 24338474 DOI: 10.1074/jbc.m113.530907] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
γ-Secretase complexes are involved in the generation of amyloid-β (Aβ) in the brain. Therefore, γ-secretase has been proposed as a potential therapeutic target in Alzheimer disease (AD). Targeting γ-secretase activity in AD requires the pharmacological dissociation of the processing of physiological relevant substrates and the generation of "toxic" Aβ. Previous reports suggest the differential targeting of γ-secretase complexes, based on their subunit composition, as a valid strategy. However, little is known about the biochemical properties of the different complexes, and key questions regarding their Aβ product profiles should be first addressed. Here, we expressed, purified, and analyzed, under the same conditions, the endopeptidase and carboxypeptidase-like activities of the four γ-secretase complexes present in humans. We find that the nature of the catalytic subunit in the complex affects both activities. Interestingly, PSEN2 complexes discriminate between the Aβ40 and Aβ38 production lines, indicating that Aβ generation in one or the other pathway can be dissociated. In contrast, the APH1 subunit mainly affects the carboxypeptidase-like activity, with APH1B complexes favoring the generation of longer Aβ peptides. In addition, we determined that expression of a single human γ-secretase complex in cell lines retains the intrinsic attributes of the protease while present in the membrane, providing validation for the in vitro studies. In conclusion, our data show that each γ-secretase complex produces a characteristic Aβ signature. The qualitative and quantitative differences between different γ-secretase complexes could be used to advance drug development in AD and other disorders.
Collapse
Affiliation(s)
- Hermien Acx
- From the Center for the Biology of Disease, Flemish Institute for Biology (VIB), 3000 Leuven, Belgium
| | | | | | | | | | | | | |
Collapse
|
27
|
Affiliation(s)
- Lucía Chávez-Gutiérrez
- VIB Center for the Biology of Disease; VIB; KULeuven; Center for Human Genetics; Leuven Belgium
| |
Collapse
|
28
|
Matta S, Van Kolen K, da Cunha R, van den Bogaart G, Mandemakers W, Miskiewicz K, De Bock PJ, Morais VA, Vilain S, Haddad D, Delbroek L, Swerts J, Chávez-Gutiérrez L, Esposito G, Daneels G, Karran E, Holt M, Gevaert K, Moechars DW, De Strooper B, Verstreken P. LRRK2 controls an EndoA phosphorylation cycle in synaptic endocytosis. Neuron 2012; 75:1008-21. [PMID: 22998870 DOI: 10.1016/j.neuron.2012.08.022] [Citation(s) in RCA: 270] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/20/2012] [Indexed: 11/25/2022]
Abstract
LRRK2 is a kinase mutated in Parkinson's disease, but how the protein affects synaptic function remains enigmatic. We identified LRRK2 as a critical regulator of EndophilinA. Using genetic and biochemical studies involving Lrrk loss-of-function mutants and Parkinson-related LRRK2(G2019S) gain-of-kinase function, we show that LRRK2 affects synaptic endocytosis by phosphorylating EndoA at S75, a residue in the BAR domain. We show that LRRK2-mediated EndoA phosphorylation has profound effects on EndoA-dependent membrane tubulation and membrane association in vitro and in vivo and on synaptic vesicle endocytosis at Drosophila neuromuscular junctions in vivo. Our work uncovers a regulatory mechanism that indicates that reduced LRRK2 kinase activity facilitates EndoA membrane association, while increased kinase activity inhibits membrane association. Consequently, both too much and too little LRRK2-dependent EndoA phosphorylation impedes synaptic endocytosis, and we propose a model in which LRRK2 kinase activity is part of an EndoA phosphorylation cycle that facilitates efficient vesicle formation at synapses.
Collapse
Affiliation(s)
- Samer Matta
- VIB Center for the Biology of Disease, 3000 Leuven, Belgium
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Guix FX, Wahle T, Vennekens K, Snellinx A, Chávez-Gutiérrez L, Ill-Raga G, Ramos-Fernandez E, Guardia-Laguarta C, Lleó A, Arimon M, Berezovska O, Muñoz FJ, Dotti CG, De Strooper B. Modification of γ-secretase by nitrosative stress links neuronal ageing to sporadic Alzheimer's disease. EMBO Mol Med 2012; 4:660-73. [PMID: 22488900 PMCID: PMC3402223 DOI: 10.1002/emmm.201200243] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [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: 12/06/2011] [Revised: 03/30/2012] [Accepted: 03/30/2012] [Indexed: 11/26/2022] Open
Abstract
Inherited familial Alzheimer's disease (AD) is characterized by small increases in the ratio of Aβ42 versus Aβ40 peptide which is thought to drive the amyloid plaque formation in the brain of these patients. Little is known however whether ageing, the major risk factor for sporadic AD, affects amyloid beta-peptide (Aβ) generation as well. Here we demonstrate that the secretion of Aβ is enhanced in an in vitro model of neuronal ageing, correlating with an increase in γ-secretase complex formation. Moreover we found that peroxynitrite (ONOO−), produced by the reaction of superoxide anion with nitric oxide, promoted the nitrotyrosination of presenilin 1 (PS1), the catalytic subunit of γ-secretase. This was associated with an increased association of the two PS1 fragments, PS1-CTF and PS1-NTF, which constitute the active catalytic centre. Furthermore, we found that peroxynitrite shifted the production of Aβ towards Aβ42 and increased the Aβ42/Aβ40 ratio. Our work identifies nitrosative stress as a potential mechanistic link between ageing and AD.
Collapse
|
30
|
Chávez-Gutiérrez L, Bammens L, Benilova I, Vandersteen A, Benurwar M, Borgers M, Lismont S, Zhou L, Van Cleynenbreugel S, Esselmann H, Wiltfang J, Serneels L, Karran E, Gijsen H, Schymkowitz J, Rousseau F, Broersen K, De Strooper B. The mechanism of γ-Secretase dysfunction in familial Alzheimer disease. EMBO J 2012; 31:2261-74. [PMID: 22505025 PMCID: PMC3364747 DOI: 10.1038/emboj.2012.79] [Citation(s) in RCA: 384] [Impact Index Per Article: 32.0] [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: 12/27/2011] [Accepted: 02/28/2012] [Indexed: 12/11/2022] Open
Abstract
Mutations in presenilin (PSEN) and amyloid precursor protein (APP) cause dominant early-onset Alzheimer's disease (AD), but the mechanism involved is debated. Here, such mutations are shown to alter γ-secretase activity, leading to changes in Aβ peptide cleavage patterns. The mechanisms by which mutations in the presenilins (PSEN) or the amyloid precursor protein (APP) genes cause familial Alzheimer disease (FAD) are controversial. FAD mutations increase the release of amyloid β (Aβ)42 relative to Aβ40 by an unknown, possibly gain-of-toxic-function, mechanism. However, many PSEN mutations paradoxically impair γ-secretase and ‘loss-of-function' mechanisms have also been postulated. Here, we use kinetic studies to demonstrate that FAD mutations affect Aβ generation via three different mechanisms, resulting in qualitative changes in the Aβ profiles, which are not limited to Aβ42. Loss of ɛ-cleavage function is not generally observed among FAD mutants. On the other hand, γ-secretase inhibitors used in the clinic appear to block the initial ɛ-cleavage step, but unexpectedly affect more selectively Notch than APP processing, while modulators act as activators of the carboxypeptidase-like (γ) activity. Overall, we provide a coherent explanation for the effect of different FAD mutations, demonstrating the importance of qualitative rather than quantitative changes in the Aβ products, and suggest fundamental improvements for current drug development efforts.
Collapse
|
31
|
Bammens L, Chávez-Gutiérrez L, Tolia A, Zwijsen A, De Strooper B. Functional and topological analysis of Pen-2, the fourth subunit of the gamma-secretase complex. J Biol Chem 2011; 286:12271-82. [PMID: 21296884 PMCID: PMC3069430 DOI: 10.1074/jbc.m110.216978] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 01/31/2011] [Indexed: 12/16/2022] Open
Abstract
The γ-secretase complex is a member of the family of intramembrane cleaving proteases, involved in the generation of the Aβ peptides in Alzheimer disease. One of the four subunits of the complex, presenilin, harbors the catalytic site, although the role of the other three subunits is less well understood. Here, we studied the role of the smallest subunit, Pen-2, in vivo and in vitro. We found a profound Notch-deficiency phenotype in Pen-2-/- embryos confirming the essential role of Pen-2 in the γ-secretase complex. We used Pen-2-/- fibroblasts to investigate the structure-function relation of Pen-2 by the scanning cysteine accessibility method. We showed that glycine 22 and proline 27 in hydrophobic domain 1 of Pen-2 are essential for complex formation and stability of γ-secretase. We also demonstrated that hydrophobic domain 1 and the loop domain of Pen-2 are located in a water-containing cavity and are in short proximity to the presenilin C-terminal fragment. We finally demonstrated the essential role of Pen-2 for the proteolytic activity of the complex. Our study supports the hypothesis that Pen-2 is more than a structural component of the γ-secretase complex and may contribute to the catalytic mechanism of the enzyme.
Collapse
Affiliation(s)
- Leen Bammens
- From the Laboratory for the Research of Neurodegenerative Diseases, Center for Human Genetics, KULeuven
- the Department of Molecular and Developmental Genetics, VIB, Herestraat 49, and
| | - Lucía Chávez-Gutiérrez
- From the Laboratory for the Research of Neurodegenerative Diseases, Center for Human Genetics, KULeuven
- the Department of Molecular and Developmental Genetics, VIB, Herestraat 49, and
| | - Alexandra Tolia
- From the Laboratory for the Research of Neurodegenerative Diseases, Center for Human Genetics, KULeuven
- the Department of Molecular and Developmental Genetics, VIB, Herestraat 49, and
| | - An Zwijsen
- the Department of Molecular and Developmental Genetics, VIB, Herestraat 49, and
- the Laboratory of Developmental Signaling, Center for Human Genetics, KULeuven, 3000 Leuven, Belgium
| | - Bart De Strooper
- From the Laboratory for the Research of Neurodegenerative Diseases, Center for Human Genetics, KULeuven
- the Department of Molecular and Developmental Genetics, VIB, Herestraat 49, and
| |
Collapse
|
32
|
Chávez-Gutiérrez L, Tolia A, Maes E, Li T, Wong PC, de Strooper B. Glu(332) in the Nicastrin ectodomain is essential for gamma-secretase complex maturation but not for its activity. J Biol Chem 2008; 283:20096-105. [PMID: 18502756 DOI: 10.1074/jbc.m803040200] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [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
The gamma-secretase complex is responsible for the proteolysis of integral membrane proteins. Nicastrin has been proposed to operate as the substrate receptor of the complex with the glutamate 332 (Glu(333) in human) serving as the anionic binding site for the alpha-amino-terminal group of substrates. The putative binding site is located within the aminopeptidase-like domain of Nicastrin. The Glu(332) is proposed to function as the counterpart of the exopeptidase Glu located in the active site of these peptidases. Although Glu(332) could bind the alpha-amino-terminal group of substrates, we hypothesized, in analogy with M28-aminopeptidases, that other residues in the putative binding site of Nicastrin should participate in the interaction as well. Surprisingly, mutagenesis of these residues affected the in vivo processing of APP and Notch substrates only weakly. In addition, the E332Q mutation, which completely abolishes the anionic alpha-amino-terminal binding function, remained fully active. When we introduced the previously characterized E332A mutation, we found strongly decreased gamma-secretase complex levels, but the remaining complex appeared as active as the wild-type complex. We confirmed in two independent in vitro assays that the specific enzymatic activity of the E332A mutant was comparable with that of the wild-type complex. Thus, Glu(332) crucially affects complex maturation rather than substrate recognition. Moreover other Nicastrin mutants, designed to either impede or alter substantially the putative binding pocket, affected only marginally gamma-secretase activity. Consequently, these studies indicate that the main role of the Glu(332) is in the maturation and assembly of gamma-secretase rather than in the recognition of the substrates.
Collapse
Affiliation(s)
- Lucía Chávez-Gutiérrez
- Center for Human Genetics, KULeuven, and Department for Molecular and Developmental Genetics, VIB4, Herestraat 49, Leuven, Belgium
| | | | | | | | | | | |
Collapse
|
33
|
de Gortari P, Vargas MA, Martínez A, García-Vázquez AI, Uribe RM, Chávez-Gutiérrez L, Magdaleno V, Boileau G, Charlí JL, Joseph-Bravo P. Stage-specific modulation of neprilysin and aminopeptidase N in the limbic system during kindling progression. J Mol Neurosci 2007; 33:252-61. [PMID: 17952634 DOI: 10.1007/s12031-007-0020-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Accepted: 10/10/2006] [Indexed: 11/30/2022]
Abstract
Aminopeptidase N (APN) and neprilysin (NEP) inactivate neuropeptides released into the brain extracellular fluid. We previously showed that the expression of pyroglutamyl peptidase II (PPII), the TRH degrading ecto-enzyme, is regulated in rat brain by amygdaline kindling, a paradigm that activates neuronal pathways in the limbic system increasing the expression of several neuropeptides including TRH and opioids. To understand the specificity of this phenomenon, we studied APN and NEP expression in brains of partially or fully kindled rats (stage II and V), sacrificed 6 h after last stimulus, compared with sham-operated animals. In situ hybridization analysis of NEP mRNA levels showed decreased expression at stage II in CA1, CA2, olfactory tubercle and medial mammillary nucleus, and increased at stage V in CA1 and CA2 cells. These changes were specific for the ipsilateral side. APN mRNA levels, semi-quantified by RT-PCR, were decreased at stage II and increased at stage V, in frontal cortex-olfactory tubercle, and hippocampus. NEP and APN enzymatic activities, determined by fluorometric assays, followed similar variations to their respective mRNA levels. The coordinated changes (in some regions) of NEP and APN expression were opposite to those previously observed for PPII mRNA and activity levels in limbic regions. These results demonstrate that expression of ectopeptidases can be regulated when peptide neurons are activated and, that regulation is enzyme-, region-, and stage-specific.
Collapse
Affiliation(s)
- Patricia de Gortari
- Div. Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz, México D.F., México
| | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Tolia A, Chávez-Gutiérrez L, De Strooper B. Contribution of presenilin transmembrane domains 6 and 7 to a water-containing cavity in the gamma-secretase complex. J Biol Chem 2006; 281:27633-42. [PMID: 16844686 DOI: 10.1074/jbc.m604997200] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Gamma-secretase is a multiprotein complex responsible for the intramembranous cleavage of the amyloid precursor protein and other type I transmembrane proteins. Mutations in Presenilin, the catalytic core of this complex, cause Alzheimer disease. Little is known about the structure of the protein and even less about the catalytic mechanism, which involves proteolytic cleavage in the hydrophobic environment of the cell membrane. It is basically unclear how water, needed to perform hydrolysis, is provided to this reaction. Presenilin transmembrane domains 6 and 7 seem critical in this regard, as each bears a critical aspartate contributing to catalytic activity. Current models imply that both aspartyl groups should closely oppose each other and have access to water. This is, however, still to be experimentally verified. Here, we have performed cysteine-scanning mutagenesis of both domains and have demonstrated that several of the introduced residues are exposed to water, providing experimental evidence for the existence of a water-filled cavity in the catalytic core of Presenilin. In addition, we have demonstrated that the two aspartates reside within this cavity and are opposed to each other in the native complex. We have also identified the conserved tyrosine 389 as a critical partner in the catalytic mechanism. Several additional amino acid substitutions affect differentially the processing of gamma-secretase substrates, implying that they contribute to enzyme specificity. Our data suggest the possibility that more selective gamma-secretase inhibitors could be designed.
Collapse
Affiliation(s)
- Alexandra Tolia
- Neuronal Cell Biology and Gene Transfer Laboratory, Center for Human Genetics, VIB4 and K. U. Leuven, Herestraat 49, 3000 Leuven, Belgium
| | | | | |
Collapse
|
35
|
Chávez-Gutiérrez L, Matta-Camacho E, Osuna J, Horjales E, Joseph-Bravo P, Maigret B, Charli JL. Homology modeling and site-directed mutagenesis of pyroglutamyl peptidase II. Insights into omega-versus aminopeptidase specificity in the M1 family. J Biol Chem 2006; 281:18581-90. [PMID: 16611635 DOI: 10.1074/jbc.m601392200] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pyroglutamyl peptidase II (PPII), a highly specific membrane-bound omegapeptidase, removes N-terminal pyroglutamyl from thyrotropin-releasing hormone (<Glu-His-Pro-NH(2)), inactivating the peptide in the extracellular space. PPII and enzymes with distinct specificities such as neutral aminopeptidase (APN), belong to the M1 metallopeptidase family. M1 aminopeptidases recognize the N-terminal amino group of substrates or inhibitors through hydrogen-bonding to two conserved residues (Gln-213 and exopeptidase motif Glu-355 in human APN), whereas interactions involved in recognition of pyroglutamyl residue by PPII are unknown. In rat PPII, the conserved exopeptidase residue is Glu-408, whereas the other one is Ser-269. Given that variations in M1 peptidase specificity are likely due to changes in the catalytic region, we constructed three-dimensional models for the catalytic domains of PPII and APN. The models showed a salt bridge interaction between PPII-Glu-408 and PPII-Lys-463, whereas the equivalent APN-Glu-355 did not participate in a salt bridge. Docking of thyrotropin-releasing hormone in PPII model suggested that the pyroglutamyl residue interacted with PPII-Ser-269. According to our models, PPII-S269Q and -K463N mutations should leave Glu-408 in a physicochemical context similar to that found in M1 aminopeptidases; alternatively, PPII-S269E replacement might be sufficient to transform PPII into an aminopeptidase. These hypotheses were supported by site-directed mutagenesis; the mutants lost omegapeptidase but displayed alanyl-aminopeptidase activity. In conclusion, recognition of a substrate without an N-terminal charge requires neutralization of the aminopeptidase anionic binding site; furthermore, shortening of side chain at PPII-269 position is required for adjustment to the pyroglutamyl residue.
Collapse
Affiliation(s)
- Lucía Chávez-Gutiérrez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Universidad Nacional Autónoma de México, 62271 Cuernavaca, Morelos, México
| | | | | | | | | | | | | |
Collapse
|