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Bhatia P, Bickle M, Agrawal AA, Truss B, Nikolaidi A, Brockmann K, Reinhardt L, Vogel S, Szegoe EM, Pal A, Hermann A, Mikicic I, Yun M, Falkenburger B, Sterneckert J. Axonal Lysosomal Assays for Characterizing the Effects of LRRK2 G2019S. Biology (Basel) 2024; 13:58. [PMID: 38275734 PMCID: PMC10813644 DOI: 10.3390/biology13010058] [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] [Received: 11/10/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024]
Abstract
The degeneration of axon terminals before the soma, referred to as "dying back", is a feature of Parkinson's disease (PD). Axonal assays are needed to model early PD pathogenesis as well as identify protective therapeutics. We hypothesized that defects in axon lysosomal trafficking as well as injury repair might be important contributing factors to "dying back" pathology in PD. Since primary human PD neurons are inaccessible, we developed assays to quantify axonal trafficking and injury repair using induced pluripotent stem cell (iPSC)-derived neurons with LRRK2 G2019S, which is one of the most common known PD mutations, and isogenic controls. We observed a subtle axonal trafficking phenotype that was partially rescued by a LRRK2 inhibitor. Mutant LRRK2 neurons showed increased phosphorylated Rab10-positive lysosomes, and lysosomal membrane damage increased LRRK2-dependent Rab10 phosphorylation. Neurons with mutant LRRK2 showed a transient increase in lysosomes at axotomy injury sites. This was a pilot study that used two patient-derived lines to develop its methodology; we observed subtle phenotypes that might correlate with heterogeneity in LRRK2-PD patients. Further analysis using additional iPSC lines is needed. Therefore, our axonal lysosomal assays can potentially be used to characterize early PD pathogenesis and test possible therapeutics.
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Affiliation(s)
- Priyanka Bhatia
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
| | - Marc Bickle
- Roche Institute of Human Biology, 4070 Basel, Switzerland
| | - Amay A. Agrawal
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
| | - Buster Truss
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
| | - Aikaterina Nikolaidi
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
| | - Kathrin Brockmann
- German Center for Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany
- Department of Neurodegenerative Diseases, Center of Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany
| | - Lydia Reinhardt
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
| | - Stefanie Vogel
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
| | - Eva M. Szegoe
- Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Arun Pal
- Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Andreas Hermann
- Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany
- Translational Neurodegeneration Section “Albrecht Kossel”, Department of Neurology, University Medical Center Rostock, University of Rostock, 18147 Rostock, Germany
- Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, University of Rostock, 18147 Rostock, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) Rostock/Greifswald, 18147 Rostock, Germany
| | - Ivan Mikicic
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
| | - Maximina Yun
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
- Max Planck Institute of Molecular Cellular Biology and Genetics, 01307 Dresden, Germany
- Physics of Life Excellence Cluster, 01307 Dresden, Germany
| | - Björn Falkenburger
- Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Jared Sterneckert
- Center for Regenerative Therapies TU Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; (P.B.)
- Medical Faculty Carl Gustav Carus of TU Dresden, 01307 Dresden, Germany
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Mulligan RJ, Winckler B. Regulation of Endosomal Trafficking by Rab7 and Its Effectors in Neurons: Clues from Charcot-Marie-Tooth 2B Disease. Biomolecules 2023; 13:1399. [PMID: 37759799 PMCID: PMC10527268 DOI: 10.3390/biom13091399] [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: 08/27/2023] [Revised: 09/09/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Intracellular endosomal trafficking controls the balance between protein degradation and synthesis, i.e., proteostasis, but also many of the cellular signaling pathways that emanate from activated growth factor receptors after endocytosis. Endosomal trafficking, sorting, and motility are coordinated by the activity of small GTPases, including Rab proteins, whose function as molecular switches direct activity at endosomal membranes through effector proteins. Rab7 is particularly important in the coordination of the degradative functions of the pathway. Rab7 effectors control endosomal maturation and the properties of late endosomal and lysosomal compartments, such as coordination of recycling, motility, and fusion with downstream compartments. The spatiotemporal regulation of endosomal receptor trafficking is particularly challenging in neurons because of their enormous size, their distinct intracellular domains with unique requirements (dendrites vs. axons), and their long lifespans as postmitotic, differentiated cells. In Charcot-Marie-Tooth 2B disease (CMT2B), familial missense mutations in Rab7 cause alterations in GTPase cycling and trafficking, leading to an ulcero-mutilating peripheral neuropathy. The prevailing hypothesis to account for CMT2B pathologies is that CMT2B-associated Rab7 alleles alter endocytic trafficking of the neurotrophin NGF and its receptor TrkA and, thereby, disrupt normal trophic signaling in the peripheral nervous system, but other Rab7-dependent pathways are also impacted. Here, using TrkA as a prototypical endocytic cargo, we review physiologic Rab7 effector interactions and control in neurons. Since neurons are among the largest cells in the body, we place particular emphasis on the temporal and spatial regulation of endosomal sorting and trafficking in neuronal processes. We further discuss the current findings in CMT2B mutant Rab7 models, the impact of mutations on effector interactions or balance, and how this dysregulation may confer disease.
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Affiliation(s)
- Ryan J. Mulligan
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22903, USA
- Medical Scientist Training Program, University of Virginia, Charlottesville, VA 22903, USA
| | - Bettina Winckler
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22903, USA
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Higerd-Rusli GP, Alsaloum M, Tyagi S, Sarveswaran N, Estacion M, Akin EJ, Dib-Hajj FB, Liu S, Sosniak D, Zhao P, Dib-Hajj SD, Waxman SG. Depolarizing Na V and Hyperpolarizing K V Channels Are Co-Trafficked in Sensory Neurons. J Neurosci 2022; 42:4794-4811. [PMID: 35589395 PMCID: PMC9188389 DOI: 10.1523/jneurosci.0058-22.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [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: 01/09/2022] [Revised: 05/04/2022] [Accepted: 05/05/2022] [Indexed: 11/21/2022] Open
Abstract
Neuronal excitability relies on coordinated action of functionally distinction channels. Voltage-gated sodium (NaV) and potassium (KV) channels have distinct but complementary roles in firing action potentials: NaV channels provide depolarizing current while KV channels provide hyperpolarizing current. Mutations and dysfunction of multiple NaV and KV channels underlie disorders of excitability, including pain and epilepsy. Modulating ion channel trafficking may offer a potential therapeutic strategy for these diseases. A fundamental question, however, is whether these channels with distinct functional roles are transported independently or packaged together in the same vesicles in sensory axons. We have used Optical Pulse-Chase Axonal Long-distance imaging to investigate trafficking of NaV and KV channels and other axonal proteins from distinct functional classes in live rodent sensory neurons (from male and female rats). We show that, similar to NaV1.7 channels, NaV1.8 and KV7.2 channels are transported in Rab6a-positive vesicles, and that each of the NaV channel isoforms expressed in healthy, mature sensory neurons (NaV1.6, NaV1.7, NaV1.8, and NaV1.9) is cotransported in the same vesicles. Further, we show that multiple axonal membrane proteins with different physiological functions (NaV1.7, KV7.2, and TNFR1) are cotransported in the same vesicles. However, vesicular packaging of axonal membrane proteins is not indiscriminate, since another axonal membrane protein (NCX2) is transported in separate vesicles. These results shed new light on the development and organization of sensory neuron membranes, revealing complex sorting of axonal proteins with diverse physiological functions into specific transport vesicles.SIGNIFICANCE STATEMENT Normal neuronal excitability is dependent on precise regulation of membrane proteins, including NaV and KV channels, and imbalance in the level of these channels at the plasma membrane could lead to excitability disorders. Ion channel trafficking could potentially be targeted therapeutically, which would require better understanding of the mechanisms underlying trafficking of functionally diverse channels. Optical Pulse-chase Axonal Long-distance imaging in live neurons permitted examination of the specificity of ion channel trafficking, revealing co-packaging of axonal proteins with opposing physiological functions into the same transport vesicles. This suggests that additional trafficking mechanisms are necessary to regulate levels of surface channels, and reveals an important consideration for therapeutic strategies that target ion channel trafficking for the treatment of excitability disorders.
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Affiliation(s)
- Grant P Higerd-Rusli
- MD/PhD Program
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Matthew Alsaloum
- MD/PhD Program
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Sidharth Tyagi
- MD/PhD Program
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Nivedita Sarveswaran
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Mark Estacion
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Elizabeth J Akin
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Fadia B Dib-Hajj
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Shujun Liu
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Daniel Sosniak
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Peng Zhao
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Sulayman D Dib-Hajj
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Stephen G Waxman
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
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Abstract
It is increasingly recognized that local protein synthesis (LPS) contributes to fundamental aspects of axon biology, in both developing and mature neurons. Mutations in RNA-binding proteins (RBPs), as central players in LPS, and other proteins affecting RNA localization and translation are associated with a range of neurological disorders, suggesting disruption of LPS may be of pathological significance. In this review, we substantiate this hypothesis by examining the link between LPS and key axonal processes, and the implicated pathophysiological consequences of dysregulated LPS. First, we describe how the length and autonomy of axons result in an exceptional reliance on LPS. We next discuss the roles of LPS in maintaining axonal structural and functional polarity and axonal trafficking. We then consider how LPS facilitates the establishment of neuronal connectivity through regulation of axonal branching and pruning, how it mediates axonal survival into adulthood and its involvement in neuronal stress responses.
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Affiliation(s)
- Julie Qiaojin Lin
- UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Island Research Building, Cambridge Biomedical Campus, Cambridge, UK
| | | | - Christine E Holt
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
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Thetiot M, Freeman SA, Roux T, Dubessy AL, Aigrot MS, Rappeneau Q, Lejeune FX, Tailleur J, Sol-Foulon N, Lubetzki C, Desmazieres A. An alternative mechanism of early nodal clustering and myelination onset in GABAergic neurons of the central nervous system. Glia 2020; 68:1891-1909. [PMID: 32119167 DOI: 10.1002/glia.23812] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 02/12/2020] [Accepted: 02/19/2020] [Indexed: 01/06/2023]
Abstract
In vertebrates, fast saltatory conduction along myelinated axons relies on the node of Ranvier. How nodes assemble on CNS neurons is not yet fully understood. We previously described that node-like clusters can form prior to myelin deposition in hippocampal GABAergic neurons and are associated with increased conduction velocity. Here, we used a live imaging approach to characterize the intrinsic mechanisms underlying the assembly of these clusters prior to myelination. We first demonstrated that their components can partially preassemble prior to membrane targeting and determined the molecular motors involved in their trafficking. We then demonstrated the key role of the protein β2Nav for node-like clustering initiation. We further assessed the fate of these clusters when myelination proceeds. Our results shed light on the intrinsic mechanisms involved in node-like clustering prior to myelination and unravel a potential role of these clusters in node of Ranvier formation and in guiding myelination onset.
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Affiliation(s)
- Melina Thetiot
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France
| | - Sean A Freeman
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France.,Assistance Publique-Hôpitaux de Paris, GH Pitié-Salpêtrière, Paris, France
| | - Thomas Roux
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France.,Assistance Publique-Hôpitaux de Paris, GH Pitié-Salpêtrière, Paris, France
| | - Anne-Laure Dubessy
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France.,Assistance Publique-Hôpitaux de Paris, GH Pitié-Salpêtrière, Paris, France
| | - Marie-Stéphane Aigrot
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France
| | - Quentin Rappeneau
- Sorbonne Université, UPMC Paris 06, Inserm, CNRS, Institut de la Vision, Paris, France
| | - François-Xavier Lejeune
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France
| | - Julien Tailleur
- Université Paris Diderot, Sorbonne Paris Cité, MSC, UMR 7057 CNRS, Paris, France
| | - Nathalie Sol-Foulon
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France
| | - Catherine Lubetzki
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France.,Assistance Publique-Hôpitaux de Paris, GH Pitié-Salpêtrière, Paris, France
| | - Anne Desmazieres
- Sorbonne Université, Inserm, CNRS, Institut du Cerveau et de la Moelle épinière, ICM-GH Pitié-Salpêtrière, Paris, France
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6
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Abo-Rady M, Kalmbach N, Pal A, Schludi C, Janosch A, Richter T, Freitag P, Bickle M, Kahlert AK, Petri S, Stefanov S, Glass H, Staege S, Just W, Bhatnagar R, Edbauer D, Hermann A, Wegner F, Sterneckert JL. Knocking out C9ORF72 Exacerbates Axonal Trafficking Defects Associated with Hexanucleotide Repeat Expansion and Reduces Levels of Heat Shock Proteins. Stem Cell Reports 2020; 14:390-405. [PMID: 32084385 PMCID: PMC7066330 DOI: 10.1016/j.stemcr.2020.01.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 01/18/2020] [Accepted: 01/21/2020] [Indexed: 12/13/2022] Open
Abstract
In amyotrophic lateral sclerosis (ALS) motor neurons (MNs) undergo dying-back, where the distal axon degenerates before the soma. The hexanucleotide repeat expansion (HRE) in C9ORF72 is the most common genetic cause of ALS, but the mechanism of pathogenesis is largely unknown with both gain- and loss-of-function mechanisms being proposed. To better understand C9ORF72-ALS pathogenesis, we generated isogenic induced pluripotent stem cells. MNs with HRE in C9ORF72 showed decreased axonal trafficking compared with gene corrected MNs. However, knocking out C9ORF72 did not recapitulate these changes in MNs from healthy controls, suggesting a gain-of-function mechanism. In contrast, knocking out C9ORF72 in MNs with HRE exacerbated axonal trafficking defects and increased apoptosis as well as decreased levels of HSP70 and HSP40, and inhibition of HSPs exacerbated ALS phenotypes in MNs with HRE. Therefore, we propose that the HRE in C9ORF72 induces ALS pathogenesis via a combination of gain- and loss-of-function mechanisms.
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Affiliation(s)
- Masin Abo-Rady
- Technische Universität Dresden, Center for Regenerative Therapies TU Dresden (CRTD), 01307 Dresden, Germany
| | - Norman Kalmbach
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Arun Pal
- Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Carina Schludi
- German Center for Neurodegenerative Diseases (DZNE) and Munich Cluster for System Neurology (SyNergy), 81377 Munich, Germany
| | - Antje Janosch
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Tanja Richter
- Institute of Human Genetics, University of Ulm, 89081 Ulm, Germany
| | - Petra Freitag
- Institut für Klinische Genetik, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
| | - Marc Bickle
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Anne-Karin Kahlert
- Institut für Klinische Genetik, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
| | - Susanne Petri
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Stefan Stefanov
- Technische Universität Dresden, Center for Regenerative Therapies TU Dresden (CRTD), 01307 Dresden, Germany
| | - Hannes Glass
- Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany; Translational Neurodegeneration Section "Albrecht-Kossel", Department of Neurology and Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, University of Rostock, 18147 Rostock, Germany
| | - Selma Staege
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany
| | - Walter Just
- Institute of Human Genetics, University of Ulm, 89081 Ulm, Germany
| | | | - Dieter Edbauer
- German Center for Neurodegenerative Diseases (DZNE) and Munich Cluster for System Neurology (SyNergy), 81377 Munich, Germany
| | - Andreas Hermann
- Technische Universität Dresden, Center for Regenerative Therapies TU Dresden (CRTD), 01307 Dresden, Germany; Department of Neurology, Technische Universität Dresden, 01307 Dresden, Germany; Translational Neurodegeneration Section "Albrecht-Kossel", Department of Neurology and Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, University of Rostock, 18147 Rostock, Germany; German Center for Neurodegenerative Diseases (DZNE) Rostock/Greifswald, 18147 Rostock, Germany
| | - Florian Wegner
- Department of Neurology, Hannover Medical School, 30625 Hannover, Germany.
| | - Jared L Sterneckert
- Technische Universität Dresden, Center for Regenerative Therapies TU Dresden (CRTD), 01307 Dresden, Germany.
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