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Borrelli E, Bandello F, Boon CJF, Carelli V, Lenaers G, Reibaldi M, Sadda SR, Sadun AA, Sarraf D, Yu-Wai-Man P, Barboni P. Mitochondrial retinopathies and optic neuropathies: The impact of retinal imaging on modern understanding of pathogenesis, diagnosis, and management. Prog Retin Eye Res 2024; 101:101264. [PMID: 38703886 DOI: 10.1016/j.preteyeres.2024.101264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 03/18/2024] [Accepted: 04/26/2024] [Indexed: 05/06/2024]
Abstract
Advancements in ocular imaging have significantly broadened our comprehension of mitochondrial retinopathies and optic neuropathies by examining the structural and pathological aspects of the retina and optic nerve in these conditions. This article aims to review the prominent imaging characteristics associated with mitochondrial retinopathies and optic neuropathies, aiming to deepen our insight into their pathogenesis and clinical features. Preceding this exploration, the article provides a detailed overview of the crucial genetic and clinical features, which is essential for the proper interpretation of in vivo imaging. More importantly, we will provide a critical analysis on how these imaging modalities could serve as biomarkers for characterization and monitoring, as well as in guiding treatment decisions. However, these imaging methods have limitations, which will be discussed along with potential strategies to mitigate them. Lastly, the article will emphasize the potential advantages and future integration of imaging techniques in evaluating patients with mitochondrial eye disorders, considering the prospects of emerging gene therapies.
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Affiliation(s)
- Enrico Borrelli
- Department of Surgical Sciences, University of Turin, Turin, Italy; Department of Ophthalmology, "City of Health and Science" Hospital, Turin, Italy.
| | - Francesco Bandello
- Vita-Salute San Raffaele University, Milan, Italy; IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Camiel J F Boon
- Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, the Netherlands; Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Valerio Carelli
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Programma di Neurogenetica, Bologna, Italy
| | - Guy Lenaers
- Equipe MitoLab, Unité MitoVasc, INSERM U1083, Université d'Angers, 49933, Angers, France; Service de Neurologie, CHU d'Angers, 49100, Angers, France
| | - Michele Reibaldi
- Department of Surgical Sciences, University of Turin, Turin, Italy; Department of Ophthalmology, "City of Health and Science" Hospital, Turin, Italy
| | - Srinivas R Sadda
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Doheny Eye Institute, Los Angeles, CA, USA
| | - Alfredo A Sadun
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Doheny Eye Institute, Los Angeles, CA, USA
| | - David Sarraf
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Retinal Disorders and Ophthalmic Genetics Division, Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Patrick Yu-Wai-Man
- John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK; Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Institute of Ophthalmology, University College London, London, UK
| | - Piero Barboni
- IRCCS San Raffaele Scientific Institute, Milan, Italy; Studio Oculistico d'Azeglio, Bologna, Italy.
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2
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Garcia-Pardo ME, Simpson JC, O’Sullivan NC. An Automated Imaging-Based Screen for Genetic Modulators of ER Organisation in Cultured Human Cells. Cells 2024; 13:577. [PMID: 38607016 PMCID: PMC11011067 DOI: 10.3390/cells13070577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/08/2024] [Accepted: 03/23/2024] [Indexed: 04/13/2024] Open
Abstract
Hereditary spastic paraplegias (HSPs) are a heterogeneous group of mono-genetic inherited neurological disorders, whose primary manifestation is the disruption of the pyramidal system, observed as a progressive impaired gait and leg spasticity in patients. Despite the large list of genes linked to this group, which exceeds 80 loci, the number of cellular functions which the gene products engage is relatively limited, among which endoplasmic reticulum (ER) morphogenesis appears central. Mutations in genes encoding ER-shaping proteins are the most common cause of HSP, highlighting the importance of correct ER organisation for long motor neuron survival. However, a major bottleneck in the study of ER morphology is the current lack of quantitative methods, with most studies to date reporting, instead, on qualitative changes. Here, we describe and apply a quantitative image-based screen to identify genetic modifiers of ER organisation using a mammalian cell culture system. An analysis reveals significant quantitative changes in tubular ER and dense sheet ER organisation caused by the siRNA-mediated knockdown of HSP-causing genes ATL1 and RTN2. This screen constitutes the first attempt to examine ER distribution in cells in an automated and high-content manner and to detect genes which impact ER organisation.
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Affiliation(s)
- M. Elena Garcia-Pardo
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, 4 Dublin, Ireland
| | - Jeremy C. Simpson
- Cell Screening Laboratory, UCD School of Biology and Environmental Science, University College Dublin, 4 Dublin, Ireland
| | - Niamh C. O’Sullivan
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, 4 Dublin, Ireland
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3
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Damiani D, Baggiani M, Della Vecchia S, Naef V, Santorelli FM. Pluripotent Stem Cells as a Preclinical Cellular Model for Studying Hereditary Spastic Paraplegias. Int J Mol Sci 2024; 25:2615. [PMID: 38473862 DOI: 10.3390/ijms25052615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 02/12/2024] [Accepted: 02/20/2024] [Indexed: 03/14/2024] Open
Abstract
Hereditary spastic paraplegias (HSPs) comprise a family of degenerative diseases mostly hitting descending axons of corticospinal neurons. Depending on the gene and mutation involved, the disease could present as a pure form with limb spasticity, or a complex form associated with cerebellar and/or cortical signs such as ataxia, dysarthria, epilepsy, and intellectual disability. The progressive nature of HSPs invariably leads patients to require walking canes or wheelchairs over time. Despite several attempts to ameliorate the life quality of patients that have been tested, current therapeutical approaches are just symptomatic, as no cure is available. Progress in research in the last two decades has identified a vast number of genes involved in HSP etiology, using cellular and animal models generated on purpose. Although unanimously considered invaluable tools for basic research, those systems are rarely predictive for the establishment of a therapeutic approach. The advent of induced pluripotent stem (iPS) cells allowed instead the direct study of morphological and molecular properties of the patient's affected neurons generated upon in vitro differentiation. In this review, we revisited all the present literature recently published regarding the use of iPS cells to differentiate HSP patient-specific neurons. Most studies have defined patient-derived neurons as a reliable model to faithfully mimic HSP in vitro, discovering original findings through immunological and -omics approaches, and providing a platform to screen novel or repurposed drugs. Thereby, one of the biggest hopes of current HSP research regards the use of patient-derived iPS cells to expand basic knowledge on the disease, while simultaneously establishing new therapeutic treatments for both generalized and personalized approaches in daily medical practice.
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Affiliation(s)
- Devid Damiani
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Fondazione Stella Maris, Via dei Giacinti 2, 56128 Pisa, Italy
| | - Matteo Baggiani
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Fondazione Stella Maris, Via dei Giacinti 2, 56128 Pisa, Italy
| | - Stefania Della Vecchia
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Fondazione Stella Maris, Via dei Giacinti 2, 56128 Pisa, Italy
- Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy
| | - Valentina Naef
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Fondazione Stella Maris, Via dei Giacinti 2, 56128 Pisa, Italy
| | - Filippo Maria Santorelli
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Fondazione Stella Maris, Via dei Giacinti 2, 56128 Pisa, Italy
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Lim JH, Kang HM, Kim DH, Jeong B, Lee DY, Lee JR, Baek JY, Cho HS, Son MY, Kim DS, Kim NS, Jung CR. ARL6IP1 gene delivery reduces neuroinflammation and neurodegenerative pathology in hereditary spastic paraplegia model. J Exp Med 2024; 221:e20230367. [PMID: 37934410 PMCID: PMC10630151 DOI: 10.1084/jem.20230367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 07/24/2023] [Accepted: 09/25/2023] [Indexed: 11/08/2023] Open
Abstract
ARL6IP1 is implicated in hereditary spastic paraplegia (HSP), but the specific pathogenic mechanism leading to neurodegeneration has not been elucidated. Here, we clarified the molecular mechanism of ARL6IP1 in HSP using in vitro and in vivo models. The Arl6ip1 knockout (KO) mouse model was generated to represent the clinically involved frameshift mutations and mimicked the HSP phenotypes. Notably, in vivo brain histopathological analysis revealed demyelination of the axon and neuroinflammation in the white matter, including the corticospinal tract. In in vitro experiments, ARL6IP1 silencing caused cell death during neuronal differentiation and mitochondrial dysfunction by dysregulated autophagy. ARL6IP1 localized on mitochondria-associated membranes (MAMs) to maintain endoplasmic reticulum and mitochondrial homeostasis via direct interaction with LC3B and BCl2L13. ARL6IP1 played a crucial role in connecting the endoplasmic reticulum and mitochondria as a member of MAMs. ARL6IP1 gene therapy reduced HSP phenotypes and restored pathophysiological changes in the Arl6ip1 KO model. Our results established that ARL6IP1 could be a potential target for HSP gene therapy.
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Affiliation(s)
- Jung Hwa Lim
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Hyun Mi Kang
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Dae Hun Kim
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Bohyeon Jeong
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Da Yong Lee
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Jae-Ran Lee
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Jeong Yeob Baek
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Hyun-Soo Cho
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Mi-Young Son
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Dae Soo Kim
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Nam-Soon Kim
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
| | - Cho-Rok Jung
- Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
- Department of Functional Genomics, Korea University of Science and Technology, Daejeon, Republic of Korea
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Haqqani AS, Mianoor Z, Star AT, Detcheverry FE, Delaney CE, Stanimirovic DB, Hamel E, Badhwar A. Proteome Profiling of Brain Vessels in a Mouse Model of Cerebrovascular Pathology. BIOLOGY 2023; 12:1500. [PMID: 38132326 PMCID: PMC10740654 DOI: 10.3390/biology12121500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 11/21/2023] [Accepted: 11/23/2023] [Indexed: 12/23/2023]
Abstract
Cerebrovascular pathology that involves altered protein levels (or signaling) of the transforming growth factor beta (TGFβ) family has been associated with various forms of age-related dementias, including Alzheimer disease (AD) and vascular cognitive impairment and dementia (VCID). Transgenic mice overexpressing TGFβ1 in the brain (TGF mice) recapitulate VCID-associated cerebrovascular pathology and develop cognitive deficits in old age or when submitted to comorbid cardiovascular risk factors for dementia. We characterized the cerebrovascular proteome of TGF mice using mass spectrometry (MS)-based quantitative proteomics. Cerebral arteries were surgically removed from 6-month-old-TGF and wild-type mice, and proteins were extracted and analyzed by gel-free nanoLC-MS/MS. We identified 3602 proteins in brain vessels, with 20 demonstrating significantly altered levels in TGF mice. For total and/or differentially expressed proteins (p ≤ 0.01, ≥ 2-fold change), using multiple databases, we (a) performed protein characterization, (b) demonstrated the presence of their RNA transcripts in both mouse and human cerebrovascular cells, and (c) demonstrated that several of these proteins were present in human extracellular vesicles (EVs) circulating in blood. Finally, using human plasma, we demonstrated the presence of several of these proteins in plasma and plasma EVs. Dysregulated proteins point to perturbed brain vessel vasomotricity, remodeling, and inflammation. Given that blood-isolated EVs are novel, attractive, and a minimally invasive biomarker discovery platform for age-related dementias, several proteins identified in this study can potentially serve as VCID markers in humans.
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Affiliation(s)
- Arsalan S. Haqqani
- Human Health Therapeutics Research Centre, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada; (A.S.H.); (A.T.S.); (C.E.D.); (D.B.S.)
| | - Zainab Mianoor
- Multiomics Investigation of Neurodegenerative Diseases (MIND) Laboratory, 4545 Chemin Queen Mary, Montreal, QC H3W 1W4, Canada; (Z.M.); (F.E.D.)
- Département de Pharmacologie et Physiologie, Institut de Génie Biomédical, Université de Montréal, 2900 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie (CRIUGM), 4545 Chemin Queen Mary, Montreal, QC H3W 1W4, Canada
| | - Alexandra T. Star
- Human Health Therapeutics Research Centre, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada; (A.S.H.); (A.T.S.); (C.E.D.); (D.B.S.)
| | - Flavie E. Detcheverry
- Multiomics Investigation of Neurodegenerative Diseases (MIND) Laboratory, 4545 Chemin Queen Mary, Montreal, QC H3W 1W4, Canada; (Z.M.); (F.E.D.)
- Département de Pharmacologie et Physiologie, Institut de Génie Biomédical, Université de Montréal, 2900 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie (CRIUGM), 4545 Chemin Queen Mary, Montreal, QC H3W 1W4, Canada
| | - Christie E. Delaney
- Human Health Therapeutics Research Centre, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada; (A.S.H.); (A.T.S.); (C.E.D.); (D.B.S.)
| | - Danica B. Stanimirovic
- Human Health Therapeutics Research Centre, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada; (A.S.H.); (A.T.S.); (C.E.D.); (D.B.S.)
| | - Edith Hamel
- Laboratory of Cerebrovascular Research, Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC H3A 2B4, Canada;
| | - AmanPreet Badhwar
- Human Health Therapeutics Research Centre, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada; (A.S.H.); (A.T.S.); (C.E.D.); (D.B.S.)
- Multiomics Investigation of Neurodegenerative Diseases (MIND) Laboratory, 4545 Chemin Queen Mary, Montreal, QC H3W 1W4, Canada; (Z.M.); (F.E.D.)
- Département de Pharmacologie et Physiologie, Institut de Génie Biomédical, Université de Montréal, 2900 Boulevard Édouard-Montpetit, Montreal, QC H3T 1J4, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie (CRIUGM), 4545 Chemin Queen Mary, Montreal, QC H3W 1W4, Canada
- Laboratory of Cerebrovascular Research, Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC H3A 2B4, Canada;
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6
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Pierga A, Matusiak R, Cauhapé M, Branchu J, Danglot L, Boutry M, Darios F. Spatacsin regulates directionality of lysosome trafficking by promoting the degradation of its partner AP5Z1. PLoS Biol 2023; 21:e3002337. [PMID: 37871017 PMCID: PMC10621996 DOI: 10.1371/journal.pbio.3002337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 11/02/2023] [Accepted: 09/15/2023] [Indexed: 10/25/2023] Open
Abstract
The endoplasmic reticulum (ER) forms contacts with the lysosomal compartment, regulating lysosome positioning and motility. The movements of lysosomes are controlled by the attachment of molecular motors to their surface. However, the molecular mechanisms by which ER controls lysosome dynamics are still elusive. Here, using mouse brain extracts and mouse embryonic fibroblasts, we demonstrate that spatacsin is an ER-resident protein regulating the formation of tubular lysosomes, which are highly dynamic. Screening for spatacsin partners required for tubular lysosome formation showed spatacsin to act by regulating protein degradation. We demonstrate that spatacsin promotes the degradation of its partner AP5Z1, which regulates the relative amount of spastizin and AP5Z1 at lysosomes. Spastizin and AP5Z1 contribute to regulate tubular lysosome formation, as well as their trafficking by interacting with anterograde and retrograde motor proteins, kinesin KIF13A and dynein/dynactin subunit p150Glued, respectively. Ultimately, investigations in polarized mouse cortical neurons in culture demonstrated that spatacsin-regulated degradation of AP5Z1 controls the directionality of lysosomes trafficking. Collectively, our results identify spatacsin as a protein regulating the directionality of lysosome trafficking.
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Affiliation(s)
- Alexandre Pierga
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Raphaël Matusiak
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Margaux Cauhapé
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Julien Branchu
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Lydia Danglot
- Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Membrane Traffic in Healthy and Diseased Brain, Université Paris Cité, Paris, France
- Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Scientific director of NeurImag facility, Université Paris Cité, Paris, France
| | - Maxime Boutry
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Frédéric Darios
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
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7
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Cohen-Barak E, Danial-Farran N, Chervinsky E, Alimi-Kasem O, Zagairy F, Livneh I, Mawassi B, Hreish M, Khayat M, Lossos A, Meiner V, Ehilevitch N, Weiss K, Shalev S. A homozygous variant in CHMP3 is associated with complex hereditary spastic paraplegia. J Med Genet 2023; 60:233-240. [PMID: 35710109 DOI: 10.1136/jmedgenet-2022-108508] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 06/07/2022] [Indexed: 11/04/2022]
Abstract
BACKGROUND Monogenic neurodegenerative diseases represent a heterogeneous group of disorders caused by mutations in genes involved in various cellular functions including autophagy, which mediates degradation of cytoplasmic contents by their transport into lysosomes. Abnormal autophagy is associated with hereditary ataxia and spastic paraplegia, amyotrophic lateral sclerosis and frontal dementia, characterised by intracellular accumulation of non-degraded proteins. We investigated the genetic basis of complex HSP in a consanguineous family of Arab-Muslim origin, consistent with autosomal recessive inheritance. METHODS Exome sequencing was followed by variant filtering and Sanger sequencing for validation and familial segregation. Studies for mRNA and protein expression used real-time PCR and immunoblots. Patients' primary fibroblasts were analysed using electron microscopy, immunofluorescence, western blot analysis and ectopic plasmid expression for its impact on autophagy. RESULTS We identified a homozygous missense variant in CHMP3 (Chr2:86507484 GRCh38 (NM_016079.4): c.518C>T, p.Thr173Ile), which encodes CHMP3 protein. Segregation analysis validated the presence of the homozygous variant in five affected individuals, while healthy family members were found either heterozygous or wild type for this variant. Primary patient's fibroblasts showed significantly reduced levels of CHMP3. Electron microscopy disclosed accumulation of endosomes, autophagosomes and autolysosomes in patient's fibroblasts, which correlated with higher levels of autophagy markers, p62 and LC3-II. Ectopic expression of wild-type CHMP3 in primary patient fibroblasts led to reduction of the p62 particles accumulation and number of endosomes and autophagosomes compared with control. CONCLUSIONS Reduced level of CHMP3 is associated with complex spastic paraplegia phenotype, through aberrant autophagy mechanisms.
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Affiliation(s)
- Eran Cohen-Barak
- Department of Dermatology, Emek Medical Center, Afula, Israel .,Technion Israel Institute of Technology, The Ruth and Bruce Rappaport Faculty of Medicine, Haifa, Israel
| | | | | | | | - Fadia Zagairy
- Department of Dermatology, Emek Medical Center, Afula, Israel
| | - Ido Livneh
- Technion Israel Institute of Technology, The Ruth and Bruce Rappaport Faculty of Medicine, Haifa, Israel
| | - Bannan Mawassi
- Department of Dermatology, Emek Medical Center, Afula, Israel
| | - Maysa Hreish
- Department of Dermatology, Emek Medical Center, Afula, Israel
| | - Morad Khayat
- Genetic Institute, Emek Medical Center, Afula, Israel
| | | | | | | | - Karin Weiss
- Technion Israel Institute of Technology, The Ruth and Bruce Rappaport Faculty of Medicine, Haifa, Israel.,Rambam Health Care Campus, Haifa, Israel
| | - Stavit Shalev
- Technion Israel Institute of Technology, The Ruth and Bruce Rappaport Faculty of Medicine, Haifa, Israel.,Emek Medical Center, Pediatric Department A and Genetic Institute, Afula, Israel
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8
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Peotter JL, Pustova I, Lettman MM, Shatadal S, Bradberry MM, Winter-Reed AD, Charan M, Sharkey EE, Alvin JR, Bren AM, Oie AK, Chapman ER, Salamat MS, Audhya A. TFG regulates secretory and endosomal sorting pathways in neurons to promote their activity and maintenance. Proc Natl Acad Sci U S A 2022; 119:e2210649119. [PMID: 36161950 PMCID: PMC9546632 DOI: 10.1073/pnas.2210649119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/18/2022] [Indexed: 02/01/2023] Open
Abstract
Molecular pathways that intrinsically regulate neuronal maintenance are poorly understood, but rare pathogenic mutations that underlie neurodegenerative disease can offer important insights into the mechanisms that facilitate lifelong neuronal function. Here, we leverage a rat model to demonstrate directly that the TFG p.R106C variant implicated previously in complicated forms of hereditary spastic paraplegia (HSP) underlies progressive spastic paraparesis with accompanying ventriculomegaly and thinning of the corpus callosum, consistent with disease phenotypes identified in adolescent patients. Analyses of primary cortical neurons obtained from CRISPR-Cas9-edited animals reveal a kinetic delay in biosynthetic secretory protein transport from the endoplasmic reticulum (ER), in agreement with prior induced pluripotent stem cell-based studies. Moreover, we identify an unexpected role for TFG in the trafficking of Rab4A-positive recycling endosomes specifically within axons and dendrites. Impaired TFG function compromises the transport of at least a subset of endosomal cargoes, which we show results in down-regulated inhibitory receptor signaling that may contribute to excitation-inhibition imbalances. In contrast, the morphology and trafficking of other organelles, including mitochondria and lysosomes, are unaffected by the TFG p.R106C mutation. Our findings demonstrate a multifaceted role for TFG in secretory and endosomal protein sorting that is unique to cells of the central nervous system and highlight the importance of these pathways to maintenance of corticospinal tract motor neurons.
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Affiliation(s)
- Jennifer L. Peotter
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Iryna Pustova
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Molly M. Lettman
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Shalini Shatadal
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Mazdak M. Bradberry
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Allison D. Winter-Reed
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Maya Charan
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Erin E. Sharkey
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - James R. Alvin
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Alyssa M. Bren
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Annika K. Oie
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Edwin R. Chapman
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
- HHMI, University of Wisconsin-Madison, Madison, WI 53705
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705
| | - M. Shahriar Salamat
- Department of Pathology and Laboratory Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
- Department of Neurological Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705
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9
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Cytosolic sequestration of spatacsin by Protein Kinase A and 14-3-3 proteins. Neurobiol Dis 2022; 174:105858. [PMID: 36096339 DOI: 10.1016/j.nbd.2022.105858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/06/2022] [Accepted: 09/08/2022] [Indexed: 11/23/2022] Open
Abstract
Mutations in SPG11, encoding spatacsin, constitute the major cause of autosomal recessive Hereditary Spastic Paraplegia (HSP) with thinning of the corpus callosum. Previous studies showed that spatacsin orchestrates cellular traffic events through the formation of a coat-like complex and its loss of function results in lysosomal and axonal transport impairments. However, the upstream mechanisms that regulate spatacsin trafficking are unknown. Here, using proteomics and CRISPR/Cas9-mediated tagging of endogenous spatacsin, we identified a subset of 14-3-3 proteins as physiological interactors of spatacsin. The interaction is modulated by Protein Kinase A (PKA)-dependent phosphorylation of spatacsin at Ser1955, which initiates spatacsin trafficking from the plasma membrane to the intracellular space. Our study provides novel insight in understanding spatacsin physio-pathological roles with mechanistic dissection of its associated pathways.
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10
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Vantaggiato C, Orso G, Guarato G, Brivio F, Napoli B, Panzeri E, Masotti S, Santorelli FM, Lamprou M, Gumeni S, Clementi E, Bassi MT. Rescue of lysosomal function as therapeutic strategy for SPG15 hereditary spastic paraplegia. Brain 2022; 146:1103-1120. [PMID: 36029068 PMCID: PMC9976989 DOI: 10.1093/brain/awac308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/22/2022] [Accepted: 08/11/2022] [Indexed: 11/14/2022] Open
Abstract
SPG15 is a hereditary spastic paraplegia subtype caused by mutations in Spastizin, a protein encoded by the ZFYVE26 gene. Spastizin is involved in autophagosome maturation and autophagic lysosome reformation and SPG15-related mutations lead to autophagic lysosome reformation defects with lysosome enlargement, free lysosome depletion and autophagosome accumulation. Symptomatic and rehabilitative treatments are the only therapy currently available for patients. Here, we targeted autophagy and lysosomes in SPG15 patient-derived cells by using a library of autophagy-modulating compounds. We identified a rose of compounds affecting intracellular calcium levels, the calcium-calpain pathway or lysosomal functions, which reduced autophagosome accumulation. The six most effective compounds were tested in vivo in a new SPG15 loss of function Drosophila model that mimicked the reported SPG15 phenotype, with autophagosome accumulation, enlarged lysosomes, reduced free lysosomes, autophagic lysosome reformation defects and locomotor deficit. These compounds, namely verapamil, Bay K8644, 2',5'-dideoxyadenosine, trehalose, Small-Molecule Enhancer of Rapamycin 28 and trifluoperazine, improved lysosome biogenesis and function in vivo, demonstrating that lysosomes are a key pharmacological target to rescue SPG15 phenotype. Among the others, the Small-Molecule Enhancer of Rapamycin 28 was the most effective, rescuing both autophagic lysosome reformation defects and locomotor deficit, and could be considered as a potential therapeutic compound for this hereditary spastic paraplegia subtype.
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Affiliation(s)
- Chiara Vantaggiato
- Correspondence to: Chiara Vantaggiato, PhD Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology, Via D. L. Monza 20 23842 Bosisio Parini, Lecco, Italy E-mail:
| | - Genny Orso
- Correspondence may also be addressed to: Genny Orso, PhD Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Largo E. Meneghetti 2, Padova, Italy E-mail:
| | - Giulia Guarato
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Largo E. Meneghetti 2, Padova, Italy
| | - Francesca Brivio
- Scientific Institute IRCCS E. Medea, Laboratory of Molecular Biology, 23842 Bosisio Parini, Lecco, Italy
| | - Barbara Napoli
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Largo E. Meneghetti 2, Padova, Italy
| | - Elena Panzeri
- Scientific Institute IRCCS E. Medea, Laboratory of Molecular Biology, 23842 Bosisio Parini, Lecco, Italy
| | - Simona Masotti
- Scientific Institute IRCCS E. Medea, Laboratory of Molecular Biology, 23842 Bosisio Parini, Lecco, Italy
| | | | - Maria Lamprou
- Department of Cell Biology and Biophysics, Faculty of Biology, National and Kapodistrian University of Athens, Athens 15784, Greece
| | - Sentiljana Gumeni
- Department of Cell Biology and Biophysics, Faculty of Biology, National and Kapodistrian University of Athens, Athens 15784, Greece
| | - Emilio Clementi
- Unit of Clinical Pharmacology, Department of Biomedical and Clinical Sciences L. Sacco, ‘Luigi Sacco’ University Hospital, Università di Milano, Milan, Italy
| | - Maria Teresa Bassi
- Scientific Institute IRCCS E. Medea, Laboratory of Molecular Biology, 23842 Bosisio Parini, Lecco, Italy
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11
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Marrone L, Marchi PM, Webster CP, Marroccella R, Coldicott I, Reynolds S, Alves-Cruzeiro J, Yang ZL, Higginbottom A, Khundadze M, Shaw PJ, Hübner CA, Livesey MR, Azzouz M. OUP accepted manuscript. Hum Mol Genet 2022; 31:2693-2710. [PMID: 35313342 PMCID: PMC9402239 DOI: 10.1093/hmg/ddac063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 02/26/2022] [Accepted: 03/10/2022] [Indexed: 11/26/2022] Open
Abstract
Hereditary spastic paraplegia type 15 (HSP15) is a neurodegenerative condition caused by the inability to produce SPG15 protein, which leads to lysosomal swelling. However, the link between lysosomal aberrations and neuronal death is poorly explored. To uncover the functional consequences of lysosomal aberrations in disease pathogenesis, we analyze human dermal fibroblasts from HSP15 patients as well as primary cortical neurons derived from an SPG15 knockout (KO) mouse model. We find that SPG15 protein loss induces defective anterograde transport, impaired neurite outgrowth, axonal swelling and reduced autophagic flux in association with the onset of lysosomal abnormalities. Additionally, we observe lipid accumulation within the lysosomal compartment, suggesting that distortions in cellular lipid homeostasis are intertwined with lysosomal alterations. We further demonstrate that SPG15 KO neurons exhibit synaptic dysfunction, accompanied by augmented vulnerability to glutamate-induced excitotoxicity. Overall, our study establishes an intimate link between lysosomal aberrations, lipid metabolism and electrophysiological impairments, suggesting that lysosomal defects are at the core of multiple neurodegenerative disease processes in HSP15.
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Affiliation(s)
- Lara Marrone
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
- Department of Neuroscience, Janssen Pharmaceutica, Beerse, Belgium
| | - Paolo M Marchi
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Christopher P Webster
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Raffaele Marroccella
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Ian Coldicott
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Steven Reynolds
- Academic Unit of Radiology, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Royal Hallamshire Hospital, Sheffield, UK
| | - João Alves-Cruzeiro
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Zih-Liang Yang
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Adrian Higginbottom
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Mukhran Khundadze
- Institute of Human Genetics, Jena University Hospital, Friedrich-Schiller-University Jena, Jena, Germany
| | - Pamela J Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Christian A Hübner
- Institute of Human Genetics, Jena University Hospital, Friedrich-Schiller-University Jena, Jena, Germany
| | - Matthew R Livesey
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Mimoun Azzouz
- To whom correspondence should be addressed. Tel: +44 1142222238; Fax: +44 (0)114 2222290; Email
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12
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Walkley SU. Rethinking lysosomes and lysosomal disease. Neurosci Lett 2021; 762:136155. [PMID: 34358625 DOI: 10.1016/j.neulet.2021.136155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 07/14/2021] [Accepted: 07/27/2021] [Indexed: 12/15/2022]
Abstract
Lysosomal storage diseases were recognized and defined over a century ago as a class of disorders affecting mostly children and causing systemic disease often accompanied by major neurological consequences. Since their discovery, research focused on understanding their causes has been an important driver of our ever-expanding knowledge of cell biology and the central role that lysosomes play in cell function. Today we recognize over 50 so-called storage diseases, with most understood at the level of gene, protein and pathway involvement, but few fully clarified in terms of how the defective lysosomal function causes brain disease; even fewer have therapies that can effectively rescue brain function. Importantly, we also recognize that storage diseases are not simply a class of lysosomal disorders all by themselves, as increasingly a critical role for the greater lysosomal system with its endosomal, autophagosomal and salvage streams has also emerged in a host of neurodevelopmental and neurodegenerative diseases. Despite persistent challenges across all aspects of these complex disorders, and as reflected in this and other articles focused on lysosomal storage diseases in this special issue of Neuroscience Letters, the progress and promise to both understand and effectively treat these conditions has never been greater.
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Affiliation(s)
- Steven U Walkley
- Department of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, NY, USA.
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13
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McGrath MJ, Eramo MJ, Gurung R, Sriratana A, Gehrig SM, Lynch GS, Lourdes SR, Koentgen F, Feeney SJ, Lazarou M, McLean CA, Mitchell CA. Defective lysosome reformation during autophagy causes skeletal muscle disease. J Clin Invest 2021; 131:135124. [PMID: 33119550 PMCID: PMC7773396 DOI: 10.1172/jci135124] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 09/23/2020] [Indexed: 12/17/2022] Open
Abstract
The regulation of autophagy-dependent lysosome homeostasis in vivo is unclear. We showed that the inositol polyphosphate 5-phosphatase INPP5K regulates autophagic lysosome reformation (ALR), a lysosome recycling pathway, in muscle. INPP5K hydrolyzes phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2] to phosphatidylinositol 4-phosphate [PI(4)P], and INPP5K mutations cause muscular dystrophy by unknown mechanisms. We report that loss of INPP5K in muscle caused severe disease, autophagy inhibition, and lysosome depletion. Reduced PI(4,5)P2 turnover on autolysosomes in Inpp5k–/– muscle suppressed autophagy and lysosome repopulation via ALR inhibition. Defective ALR in Inpp5k–/– myoblasts was characterized by enlarged autolysosomes and the persistence of hyperextended reformation tubules, structures that participate in membrane recycling to form lysosomes. Reduced disengagement of the PI(4,5)P2 effector clathrin was observed on reformation tubules, which we propose interfered with ALR completion. Inhibition of PI(4,5)P2 synthesis or expression of WT INPP5K but not INPP5K disease mutants in INPP5K-depleted myoblasts restored lysosomal homeostasis. Therefore, bidirectional interconversion of PI(4)P/PI(4,5)P2 on autolysosomes was integral to lysosome replenishment and autophagy function in muscle. Activation of TFEB-dependent de novo lysosome biogenesis did not compensate for loss of ALR in Inpp5k–/– muscle, revealing a dependence on this lysosome recycling pathway. Therefore, in muscle, ALR is indispensable for lysosome homeostasis during autophagy and when defective is associated with muscular dystrophy.
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Affiliation(s)
- Meagan J McGrath
- Cancer Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Matthew J Eramo
- Cancer Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Rajendra Gurung
- Cancer Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Absorn Sriratana
- Cancer Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Stefan M Gehrig
- Centre for Muscle Research, Department of Physiology, School of Biomedical Sciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Gordon S Lynch
- Centre for Muscle Research, Department of Physiology, School of Biomedical Sciences, The University of Melbourne, Melbourne, Victoria, Australia
| | - Sonia Raveena Lourdes
- Cancer Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Frank Koentgen
- Ozgene Pty Ltd, Bentley, Perth, Western Australia, Australia
| | - Sandra J Feeney
- Cancer Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Michael Lazarou
- Neuroscience Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Catriona A McLean
- Department of Anatomical Pathology, Alfred Hospital, Prahran, Melbourne, Victoria, Australia
| | - Christina A Mitchell
- Cancer Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Melbourne, Victoria, Australia
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14
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Darios F, Coarelli G, Durr A. Genetics in hereditary spastic paraplegias: Essential but not enough. Curr Opin Neurobiol 2021; 72:8-14. [PMID: 34403957 DOI: 10.1016/j.conb.2021.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/04/2021] [Accepted: 07/14/2021] [Indexed: 12/01/2022]
Abstract
Hereditary spastic paraplegias consist of a group of rare neurodegenerative diseases characterized by lower limb spasticity. These inherited Mendelian disorders show high genetic variability associated with wide clinical diversity. Pathophysiological investigations have suggested that mutations in genes affecting the same cellular pathway generally lead to similar clinical symptoms, highlighting the importance of genetic mutation in these diseases. However, phenotype-genotype correlations have failed to explain the observed large inter-individual variability linked to mutations in a single gene, suggesting that genetics alone is not sufficient to explain symptom diversity. The identification of biomarkers, such as neurofilament light chain, could fill the gap and predict disease evolution.
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Affiliation(s)
- Frédéric Darios
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm U1127, CNRS UMR7225, Paris, 75013, France.
| | - Giulia Coarelli
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm U1127, CNRS UMR7225, Paris, 75013, France; AP-HP, Hôpital de la Pitié Salpêtrière, Paris, 75013, France
| | - Alexandra Durr
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm U1127, CNRS UMR7225, Paris, 75013, France; AP-HP, Hôpital de la Pitié Salpêtrière, Paris, 75013, France.
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15
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Güner F, Pozner T, Krach F, Prots I, Loskarn S, Schlötzer-Schrehardt U, Winkler J, Winner B, Regensburger M. Axon-Specific Mitochondrial Pathology in SPG11 Alpha Motor Neurons. Front Neurosci 2021; 15:680572. [PMID: 34326717 PMCID: PMC8314181 DOI: 10.3389/fnins.2021.680572] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 06/14/2021] [Indexed: 11/13/2022] Open
Abstract
Pathogenic variants in SPG11 are the most frequent cause of autosomal recessive complicated hereditary spastic paraplegia (HSP). In addition to spastic paraplegia caused by corticospinal degeneration, most patients are significantly affected by progressive weakness and muscle wasting due to alpha motor neuron (MN) degeneration. Mitochondria play a crucial role in neuronal health, and mitochondrial deficits were reported in other types of HSPs. To investigate whether mitochondrial pathology is present in SPG11, we differentiated MNs from induced pluripotent stem cells derived from SPG11 patients and controls. MN derived from human embryonic stem cells and an isogenic SPG11 knockout line were also included in the study. Morphological analysis of mitochondria in the MN soma versus neurites revealed specific alterations of mitochondrial morphology within SPG11 neurites, but not within the soma. In addition, impaired mitochondrial membrane potential was indicative of mitochondrial dysfunction. Moreover, we reveal neuritic aggregates further supporting neurite pathology in SPG11. Correspondingly, using a microfluidic-based MN culture system, we demonstrate that axonal mitochondrial transport was significantly impaired in SPG11. Overall, our data demonstrate that alterations in morphology, function, and transport of mitochondria are an important feature of axonal dysfunction in SPG11 MNs.
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Affiliation(s)
- Fabian Güner
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Tatyana Pozner
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Florian Krach
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Iryna Prots
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Sandra Loskarn
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | | | - Jürgen Winkler
- Department of Molecular Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Center for Rare Diseases Erlangen, University Hospital Erlangen, Erlangen, Germany
| | - Beate Winner
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Center for Rare Diseases Erlangen, University Hospital Erlangen, Erlangen, Germany
| | - Martin Regensburger
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Department of Molecular Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.,Center for Rare Diseases Erlangen, University Hospital Erlangen, Erlangen, Germany
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16
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Toupenet Marchesi L, Leblanc M, Stevanin G. Current Knowledge of Endolysosomal and Autophagy Defects in Hereditary Spastic Paraplegia. Cells 2021; 10:cells10071678. [PMID: 34359848 PMCID: PMC8307360 DOI: 10.3390/cells10071678] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/26/2021] [Accepted: 06/29/2021] [Indexed: 12/25/2022] Open
Abstract
Hereditary spastic paraplegia (HSP) refers to a group of neurological disorders involving the degeneration of motor neurons. Due to their clinical and genetic heterogeneity, finding common effective therapeutics is difficult. Therefore, a better understanding of the common pathological mechanisms is necessary. The role of several HSP genes/proteins is linked to the endolysosomal and autophagic pathways, suggesting a functional convergence. Furthermore, impairment of these pathways is particularly interesting since it has been linked to other neurodegenerative diseases, which would suggest that the nervous system is particularly sensitive to the disruption of the endolysosomal and autophagic systems. In this review, we will summarize the involvement of HSP proteins in the endolysosomal and autophagic pathways in order to clarify their functioning and decipher some of the pathological mechanisms leading to HSP.
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Affiliation(s)
- Liriopé Toupenet Marchesi
- Institut du Cerveau—Paris Brain Institute—ICM, INSERM, CNRS, APHP, Sorbonne Université, Pitié-Salpêtrière Hospital, 75013 Paris, France; (L.T.M.); (M.L.)
- Neurogenetics Team, EPHE, Paris Sciences Lettres Research University, 75000 Paris, France
| | - Marion Leblanc
- Institut du Cerveau—Paris Brain Institute—ICM, INSERM, CNRS, APHP, Sorbonne Université, Pitié-Salpêtrière Hospital, 75013 Paris, France; (L.T.M.); (M.L.)
- Neurogenetics Team, EPHE, Paris Sciences Lettres Research University, 75000 Paris, France
| | - Giovanni Stevanin
- Institut du Cerveau—Paris Brain Institute—ICM, INSERM, CNRS, APHP, Sorbonne Université, Pitié-Salpêtrière Hospital, 75013 Paris, France; (L.T.M.); (M.L.)
- Neurogenetics Team, EPHE, Paris Sciences Lettres Research University, 75000 Paris, France
- Correspondence:
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17
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Zapata-Muñoz J, Villarejo-Zori B, Largo-Barrientos P, Boya P. Towards a better understanding of the neuro-developmental role of autophagy in sickness and in health. Cell Stress 2021; 5:99-118. [PMID: 34308255 PMCID: PMC8283300 DOI: 10.15698/cst2021.07.253] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 01/18/2023] Open
Abstract
Autophagy is a critical cellular process by which biomolecules and cellular organelles are degraded in an orderly manner inside lysosomes. This process is particularly important in neurons: these post-mitotic cells cannot divide or be easily replaced and are therefore especially sensitive to the accumulation of toxic proteins and damaged organelles. Dysregulation of neuronal autophagy is well documented in a range of neurodegenerative diseases. However, growing evidence indicates that autophagy also critically contributes to neurodevelopmental cellular processes, including neurogenesis, maintenance of neural stem cell homeostasis, differentiation, metabolic reprogramming, and synaptic remodelling. These findings implicate autophagy in neurodevelopmental disorders. In this review we discuss the current understanding of the role of autophagy in neurodevelopment and neurodevelopmental disorders, as well as currently available tools and techniques that can be used to further investigate this association.
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Affiliation(s)
- Juan Zapata-Muñoz
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| | | | | | - Patricia Boya
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
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18
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Khundadze M, Ribaudo F, Hussain A, Stahlberg H, Brocke-Ahmadinejad N, Franzka P, Varga RE, Zarkovic M, Pungsrinont T, Kokal M, Ganley IG, Beetz C, Sylvester M, Hübner CA. Mouse models for hereditary spastic paraplegia uncover a role of PI4K2A in autophagic lysosome reformation. Autophagy 2021; 17:3690-3706. [PMID: 33618608 PMCID: PMC8632344 DOI: 10.1080/15548627.2021.1891848] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Hereditary spastic paraplegia (HSP) denotes genetically heterogeneous disorders characterized by leg spasticity due to degeneration of corticospinal axons. SPG11 and SPG15 have a similar clinical course and together are the most prevalent autosomal recessive HSP entity. The respective proteins play a role for macroautophagy/autophagy and autophagic lysosome reformation (ALR). Here, we report that spg11 and zfyve26 KO mice developed motor impairments within the same course of time. This correlated with enhanced accumulation of autofluorescent material in neurons and progressive neuron loss. In agreement with defective ALR, tubulation events were diminished in starved KO mouse embryonic fibroblasts (MEFs) and lysosomes decreased in neurons of KO brain sections. Confirming that both proteins act in the same molecular pathway, the pathologies were not aggravated upon simultaneous disruption of both. We further show that PI4K2A (phosphatidylinositol 4-kinase type 2 alpha), which phosphorylates phosphatidylinositol to phosphatidylinositol-4-phosphate (PtdIns4P), accumulated in autofluorescent deposits isolated from KO but not WT brains. Elevated PI4K2A abundance was already found at autolysosomes of neurons of presymptomatic KO mice. Immunolabelings further suggested higher levels of PtdIns4P at LAMP1-positive structures in starved KO MEFs. An increased association with LAMP1-positive structures was also observed for clathrin and DNM2/dynamin 2, which are important effectors of ALR recruited by phospholipids. Because PI4K2A overexpression impaired ALR, while its knockdown increased tubulation, we conclude that PI4K2A modulates phosphoinositide levels at autolysosomes and thus the recruitment of downstream effectors of ALR. Therefore, PI4K2A may play an important role in the pathogenesis of SPG11 and SPG15. Abbreviations: ALR: autophagic lysosome reformation; AP-5: adaptor protein complex 5; BFP: blue fluorescent protein; dKO: double knockout; EBSS: Earle’s balanced salt solution; FBA: foot base angle; GFP: green fluorescent protein; HSP: hereditary spastic paraplegia; KO: knockout; LAMP1: lysosomal-associated membrane protein 1; MAP1LC3B/LC3: microtubule-associated protein 1 light chain 3 beta; MEF: mouse embryonic fibroblast; SQSTM1/p62: sequestosome 1; PI4K2A: phosphatidylinositol 4-kinase type 2 alpha; PtdIns3P: phosphatidylinositol-3-phosphate; PtdIns4P: phosphatidylinositol-4-phosphate; RFP: red fluorescent protein; SPG: spastic paraplegia gene; TGN: trans-Golgi network; WT: wild type
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Affiliation(s)
- Mukhran Khundadze
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Federico Ribaudo
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Adeela Hussain
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Henry Stahlberg
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Nahal Brocke-Ahmadinejad
- Core Facility Mass Spectrometry, Institute of Biochemistry and Molecular Biology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Patricia Franzka
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Rita-Eva Varga
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Milena Zarkovic
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Thanakorn Pungsrinont
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Miriam Kokal
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
| | - Ian G Ganley
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee, Scotland
| | - Christian Beetz
- Institute of Clinical Chemistry, University Hospital Jena, Friedrich-Schiller-University Jena, Germany; Current Affiliation: Centogene GmbH, Rostock, Germany
| | - Marc Sylvester
- Core Facility Mass Spectrometry, Institute of Biochemistry and Molecular Biology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Christian A Hübner
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena, Germany
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19
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Ddhd1 knockout mouse as a model of locomotive and physiological abnormality in familial spastic paraplegia. Biosci Rep 2021; 41:227847. [PMID: 33600578 PMCID: PMC7921290 DOI: 10.1042/bsr20204171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/04/2021] [Accepted: 02/11/2021] [Indexed: 11/17/2022] Open
Abstract
We have previously reported a novel homozygous 4-bp deletion in DDHD1 as the responsible variant for spastic paraplegia type 28 (SPG28; OMIM#609340). The variant causes a frameshift, resulting in a functionally null allele in the patient. DDHD1 encodes phospholipase A1 (PLA1) catalyzing phosphatidylinositol to lysophosphatidylinositol (LPI). To clarify the pathogenic mechanism of SPG28, we established Ddhd1 knockout mice (Ddhd1[-/-]) carrying a 5-bp deletion in Ddhd1, resulting in a premature termination of translation at a position similar to that of the patient. We observed a significant decrease in foot-base angle (FBA) in aged Ddhd1(-/-) (24 months of age) and a significant decrease in LPI 20:4 (sn-2) in Ddhd1(-/-) cerebra (26 months of age). These changes in FBA were not observed in 14 months of age. We also observed significant changes of expression levels of 22 genes in the Ddhd1(-/-) cerebra (26 months of age). Gene Ontology (GO) terms relating to the nervous system and cell-cell communications were significantly enriched. We conclude that the reduced signaling of LPI 20:4 (sn-2) by PLA1 dysfunction is responsible for the locomotive abnormality in SPG28, further suggesting that the reduction of downstream signaling such as GPR55 which is agonized by LPI is involved in the pathogenesis of SPG28.
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20
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Hsu SL, Lu YJ, Tsai YS, Chao HC, Fuh JL, Liao YC, Lee YC. Investigating ZFYVE26 mutations in a Taiwanese cohort with hereditary spastic paraplegia. J Formos Med Assoc 2021; 121:126-133. [PMID: 33637369 DOI: 10.1016/j.jfma.2021.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/28/2020] [Accepted: 02/02/2021] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND/PURPOSE Hereditary spastic paraplegia (HSP) is a heterogeneous group of inherited neurodegenerative disorders characterized by slowly progressive lower limbs spasticity and weakness. HSP type 15 (SPG15) is an autosomal recessive subtype caused by ZFYVE26 mutations. The aim of this study was to investigate the frequency and clinical and genetic features of ZFYVE26 mutations in a Taiwanese HSP cohort. METHODS Mutational analysis of the coding regions of ZFYVE26 was performed by targeted resequencing in the 195 unrelated Taiwanese patients with HSP. All of the patients were of Han Chinese ethnicity. Clinical, neuropsychological, electrophysiological evaluations and imaging studies were collected. RESULTS Among the 195 patients, only one SPG15 patient was identified. The patient had a novel recessive ZFYVE26 frameshift truncating mutation, p.R1806Gfs∗36 (c.5415delC), and presented with insidious onset spastic weakness of lower-extremities and cognitive impairment. Neuropsychological assessment revealed deficits in executive function, visual naming, category verbal fluency, and manual dexterity. Brain MRI showed thin corpus callosum and the "ears of lynx" sign. CONCLUSION SPG15 accounts for approximately 0.5% (1/195) of the Taiwanese HSP cohort. This study identified the first Taiwanese SPG15 case and delineated the clinical, genetic, neuropsychological, and neuroimaging features. These findings expand the mutational spectrum of ZFYVE26 and also broaden the knowledge of clinical and neuropsychological characteristics of SPG15.
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Affiliation(s)
- Shao-Lun Hsu
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Yi-Jiun Lu
- Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Yu-Shuen Tsai
- Center for Systems and Synthetic Biology, National Yang-Ming University, Taipei, Taiwan
| | - Hua-Chuan Chao
- Division of Neurology, Department of Medicine, Taipei Veterans General Hospital, Taoyuan Branch, Taoyuan, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Jong-Ling Fuh
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan; Brain Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Yi-Chu Liao
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan; Brain Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Yi-Chung Lee
- Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan; Brain Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan.
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21
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Edmison D, Wang L, Gowrishankar S. Lysosome Function and Dysfunction in Hereditary Spastic Paraplegias. Brain Sci 2021; 11:152. [PMID: 33498913 PMCID: PMC7911997 DOI: 10.3390/brainsci11020152] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/15/2021] [Accepted: 01/21/2021] [Indexed: 12/13/2022] Open
Abstract
Hereditary Spastic Paraplegias (HSPs) are a genetically diverse group of inherited neurological diseases with over 80 associated gene loci. Over the last decade, research into mechanisms underlying HSPs has led to an emerging interest in lysosome dysfunction. In this review, we highlight the different classes of HSPs that have been linked to lysosome defects: (1) a subset of complex HSPs where mutations in lysosomal genes are causally linked to the diseases, (2) other complex HSPs where mutation in genes encoding membrane trafficking adaptors lead to lysosomal defects, and (3) a subset of HSPs where mutations affect genes encoding proteins whose function is primarily linked to a different cellular component or organelle such as microtubule severing and Endoplasmic Reticulum-shaping, while also altering to lysosomes. Interestingly, aberrant axonal lysosomes, associated with the latter two subsets of HSPs, are a key feature observed in other neurodegenerative diseases such as Alzheimer's disease. We discuss how altered lysosome function and trafficking may be a critical contributor to HSP pathology and highlight the need for examining these features in the cortico-spinal motor neurons of HSP mutant models.
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Affiliation(s)
| | | | - Swetha Gowrishankar
- Department of Anatomy and Cell Biology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA; (D.E.); (L.W.)
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22
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Hirst J, Hesketh GG, Gingras AC, Robinson MS. Rag GTPases and phosphatidylinositol 3-phosphate mediate recruitment of the AP-5/SPG11/SPG15 complex. J Cell Biol 2021; 220:211690. [PMID: 33464297 PMCID: PMC7814351 DOI: 10.1083/jcb.202002075] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/21/2020] [Accepted: 12/02/2020] [Indexed: 12/31/2022] Open
Abstract
Adaptor protein complex 5 (AP-5) and its partners, SPG11 and SPG15, are recruited onto late endosomes and lysosomes. Here we show that recruitment of AP-5/SPG11/SPG15 is enhanced in starved cells and occurs by coincidence detection, requiring both phosphatidylinositol 3-phosphate (PI3P) and Rag GTPases. PI3P binding is via the SPG15 FYVE domain, which, on its own, localizes to early endosomes. GDP-locked RagC promotes recruitment of AP-5/SPG11/SPG15, while GTP-locked RagA prevents its recruitment. Our results uncover an interplay between AP-5/SPG11/SPG15 and the mTORC1 pathway and help to explain the phenotype of AP-5/SPG11/SPG15 deficiency in patients, including the defect in autophagic lysosome reformation.
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Affiliation(s)
- Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK,Jennifer Hirst:
| | - Geoffrey G. Hesketh
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Margaret S. Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK,Correspondence to Margaret S. Robinson:
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23
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Wolff H, Jakoby M, Stephan L, Koebke E, Hülskamp M. Heat Stress-Dependent Association of Membrane Trafficking Proteins With mRNPs Is Selective. FRONTIERS IN PLANT SCIENCE 2021; 12:670499. [PMID: 34249042 PMCID: PMC8264791 DOI: 10.3389/fpls.2021.670499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 05/27/2021] [Indexed: 05/03/2023]
Abstract
The Arabidopsis AAA ATPase SKD1 is essential for ESCRT-dependent endosomal sorting by mediating the disassembly of the ESCRTIII complex in an ATP-dependent manner. In this study, we show that SKD1 localizes to messenger ribonucleoprotein complexes upon heat stress. Consistent with this, the interactome of SKD1 revealed differential interactions under normal and stress conditions and included membrane transport proteins as well as proteins associated with RNA metabolism. Localization studies with selected interactome proteins revealed that not only RNA associated proteins but also several ESCRTIII and membrane trafficking proteins were recruited to messenger ribonucleoprotein granules after heat stress.
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Affiliation(s)
- Heike Wolff
- Cluster of Excellence on Plant Sciences (CEPLAS), Botanical Institute, Cologne University, Cologne, Germany
| | - Marc Jakoby
- Botanical Institute, Biocenter, Cologne University, Cologne, Germany
| | - Lisa Stephan
- Botanical Institute, Biocenter, Cologne University, Cologne, Germany
| | - Eva Koebke
- Botanical Institute, Biocenter, Cologne University, Cologne, Germany
| | - Martin Hülskamp
- Botanical Institute, Biocenter, Cologne University, Cologne, Germany
- *Correspondence: Martin Hülskamp
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24
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Pozner T, Regensburger M, Engelhorn T, Winkler J, Winner B. Janus-faced spatacsin (SPG11): involvement in neurodevelopment and multisystem neurodegeneration. Brain 2020; 143:2369-2379. [PMID: 32355960 PMCID: PMC7447516 DOI: 10.1093/brain/awaa099] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/12/2020] [Accepted: 02/05/2020] [Indexed: 12/11/2022] Open
Abstract
Hereditary spastic paraplegia (HSP) is a heterogeneous group of rare motor neuron disorders characterized by progressive weakness and spasticity of the lower limbs. HSP type 11 (SPG11-HSP) is linked to pathogenic variants in the SPG11 gene and it represents the most frequent form of complex autosomal recessive HSP. The majority of SPG11-HSP patients exhibit additional neurological symptoms such as cognitive decline, thin corpus callosum, and peripheral neuropathy. Yet, the mechanisms of SPG11-linked spectrum diseases are largely unknown. Recent findings indicate that spatacsin, the 280 kDa protein encoded by SPG11, may impact the autophagy-lysosomal machinery. In this update, we summarize the current knowledge of SPG11-HSP. In addition to clinical symptoms and differential diagnosis, our work aims to link the different clinical manifestations with the respective structural abnormalities and cellular in vitro phenotypes. Moreover, we describe the impact of localization and function of spatacsin in different neuronal systems. Ultimately, we propose a model in which spatacsin bridges between neurodevelopmental and neurodegenerative phenotypes of SPG11-linked disorders.
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Affiliation(s)
- Tatyana Pozner
- Department of Stem Cell Biology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Martin Regensburger
- Department of Stem Cell Biology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany.,Department of Neurology, FAU Erlangen-Nürnberg, Erlangen, Germany.,Department of Molecular Neurology, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Tobias Engelhorn
- Department of Neuroradiology, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Jürgen Winkler
- Department of Molecular Neurology, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Beate Winner
- Department of Stem Cell Biology, Friedrich-Alexander University (FAU) Erlangen-Nürnberg, Erlangen, Germany.,Center of Rare Diseases Erlangen (ZSEER), FAU Erlangen-Nürnberg, Erlangen, Germany
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25
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Laulajainen‐Hongisto A, Lyly A, Hanif T, Dhaygude K, Kankainen M, Renkonen R, Donner K, Mattila P, Jartti T, Bousquet J, Kauppi P, Toppila‐Salmi S. Genomics of asthma, allergy and chronic rhinosinusitis: novel concepts and relevance in airway mucosa. Clin Transl Allergy 2020; 10:45. [PMID: 33133517 PMCID: PMC7592594 DOI: 10.1186/s13601-020-00347-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 09/25/2020] [Indexed: 12/14/2022] Open
Abstract
Genome wide association studies (GWASs) have revealed several airway disease-associated risk loci. Their role in the onset of asthma, allergic rhinitis (AR) or chronic rhinosinusitis (CRS), however, is not yet fully understood. The aim of this review is to evaluate the airway relevance of loci and genes identified in GWAS studies. GWASs were searched from databases, and a list of loci associating significantly (p < 10-8) with asthma, AR and CRS was created. This yielded a total of 267 significantly asthma/AR-associated loci from 31 GWASs. No significant CRS -associated loci were found in this search. A total of 170 protein coding genes were connected to these loci. Of these, 76/170 (44%) showed bronchial epithelial protein expression in stained microscopic figures of Human Protein Atlas (HPA), and 61/170 (36%) had a literature report of having airway epithelial function. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analyses were performed, and 19 functional protein categories were found as significantly (p < 0.05) enriched among these genes. These were related to cytokine production, cell activation and adaptive immune response, and all were strongly connected in network analysis. We also identified 15 protein pathways that were significantly (p < 0.05) enriched in these genes, related to T-helper cell differentiation, virus infection, JAK-STAT signaling pathway, and asthma. A third of GWAS-level risk loci genes of asthma or AR seemed to have airway epithelial functions according to our database and literature searches. In addition, many of the risk loci genes were immunity related. Some risk loci genes also related to metabolism, neuro-musculoskeletal or other functions. Functions overlapped and formed a strong network in our pathway analyses and are worth future studies of biomarker and therapeutics.
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Affiliation(s)
- Anu Laulajainen‐Hongisto
- Department of Otorhinolaryngology–Head and Neck SurgeryUniversity of Helsinki and Helsinki University HospitalP.O.Box 263Kasarmikatu 11‐1300029 HUSHelsinkiFinland
- Laboratory of Cellular and Molecular ImmunologyInstitute of Microbiology of the Czech Academy of SciencesPragueCzech Republic
| | - Annina Lyly
- Department of Otorhinolaryngology–Head and Neck SurgeryUniversity of Helsinki and Helsinki University HospitalP.O.Box 263Kasarmikatu 11‐1300029 HUSHelsinkiFinland
- Skin and Allergy HospitalUniversity of Helsinki and Helsinki University HospitalHelsinkiFinland
| | | | | | - Matti Kankainen
- HUS Diagnostic CenterHelsinki University HospitalHelsinkiFinland
- Hematology Research Unit HelsinkiDepartment of HematologyHelsinki University Hospital Comprehensive Cancer CenterHelsinkiFinland
- Translational Immunology Research Program and Department of Clinical ChemistryUniversity of HelsinkiHelsinkiFinland
| | - Risto Renkonen
- Haartman InstituteUniversity of HelsinkiHelsinkiFinland
- HUS Diagnostic CenterHelsinki University HospitalHelsinkiFinland
| | - Kati Donner
- Hematology Research Unit HelsinkiDepartment of HematologyHelsinki University Hospital Comprehensive Cancer CenterHelsinkiFinland
| | - Pirkko Mattila
- Haartman InstituteUniversity of HelsinkiHelsinkiFinland
- Hematology Research Unit HelsinkiDepartment of HematologyHelsinki University Hospital Comprehensive Cancer CenterHelsinkiFinland
| | - Tuomas Jartti
- Department of Pediatrics and Adolescent MedicineTurku University Hospital and University of TurkuTurkuFinland
| | - Jean Bousquet
- Université MontpellierMontpellierFrance
- MACVIA‐FranceMontpellierFrance
- Corporate Member of Freie Universität BerlinHumboldt‐Universität Zu BerlinBerlin Institute of HealthComprehensive Allergy CenterDepartment of Dermatology and AllergyCharité–Universitätsmedizin BerlinBerlinGermany
| | - Paula Kauppi
- Skin and Allergy HospitalUniversity of Helsinki and Helsinki University HospitalHelsinkiFinland
| | - Sanna Toppila‐Salmi
- Skin and Allergy HospitalUniversity of Helsinki and Helsinki University HospitalHelsinkiFinland
- Haartman InstituteUniversity of HelsinkiHelsinkiFinland
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26
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Ebbinghaus M, Tuchscherr L, Segond von Banchet G, Liebmann L, Adams V, Gajda M, Hübner CA, Kurth I, Schaible HG. Gain-of-function mutation in SCN11A causes itch and affects neurogenic inflammation and muscle function in Scn11a+/L799P mice. PLoS One 2020; 15:e0237101. [PMID: 32817686 PMCID: PMC7440628 DOI: 10.1371/journal.pone.0237101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/20/2020] [Indexed: 12/22/2022] Open
Abstract
Mutations in the genes encoding for voltage-gated sodium channels cause profound sensory disturbances and other symptoms dependent on the distribution of a particular channel subtype in different organs. Humans with the gain-of-function mutation p.Leu811Pro in SCN11A (encoding for the voltage-gated Nav1.9 channel) exhibit congenital insensitivity to pain, pruritus, self-inflicted injuries, slow healing wounds, muscle weakness, Charcot-like arthropathies, and intestinal dysmotility. As already shown, knock-in mice (Scn11a+/L799P) carrying the orthologous mutation p.Leu799Pro replicate reduced pain sensitivity and show frequent tissue lesions. In the present study we explored whether Scn11a+/L799P mice develop also pruritus, muscle weakness, and changes in gastrointestinal transit time. Furthermore, we analyzed morphological and functional differences in nerves, skeletal muscle, joints and small intestine from Scn11a+/L799P and Scn11a+/+ wild type mice. Compared to Scn11a+/+ mice, Scn11a+/L799P mice showed enhanced scratching bouts before skin lesions developed, indicating pruritus. Scn11a+/L799P mice exhibited reduced grip strength, but no disturbances in motor coordination. Skeletal muscle fiber types and joint architecture were unaltered in Scn11a+/L799P mice. Their gastrointestinal transit time was unaltered. The small intestine from Scn11a+/L799P showed a small shift towards less frequent peristaltic movements. Similar proportions of lumbar dorsal root ganglion neurons from Scn11a+/L799P and Scn11a+/+ mice were calcitonin gene-related peptide (CGRP-) positive, but isolated sciatic nerves from Scn11a+/L799P mice exhibited a significant reduction of the capsaicin-evoked release of CGRP indicating reduced neurogenic inflammation. These data indicate important Nav1.9 channel functions in several organs in both humans and mice. They support the pathophysiological relevance of increased basal activity of Nav1.9 channels for sensory abnormalities (pain and itch) and suggest resulting malfunctions of the motor system and of the gastrointestinal tract. Scn11a+/L799P mice are suitable to investigate the role of Nav1.9, and to explore the pathophysiological changes and mechanisms which develop as a consequence of Nav1.9 hyperactivity.
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Affiliation(s)
- Matthias Ebbinghaus
- Institute of Physiology 1/Neurophysiology, University Hospital - Friedrich Schiller University Jena, Jena, Germany
| | - Lorena Tuchscherr
- Institute of Medical Microbiology, University Hospital - Friedrich Schiller University Jena, Jena, Germany
| | - Gisela Segond von Banchet
- Institute of Physiology 1/Neurophysiology, University Hospital - Friedrich Schiller University Jena, Jena, Germany
| | - Lutz Liebmann
- Institute of Human Genetics, University Hospital - Friedrich Schiller University Jena, Jena, Germany
| | - Volker Adams
- Laboratory of Molecular and Experimental Cardiology, Heart Center Dresden, Technische Universität Dresden, Dresden, Germany
| | - Mieczyslaw Gajda
- Institute of Pathology, University Hospital - Friedrich Schiller University Jena, Jena, Germany
| | - Christian A. Hübner
- Institute of Human Genetics, University Hospital - Friedrich Schiller University Jena, Jena, Germany
| | - Ingo Kurth
- Institute of Human Genetics, Medical Faculty - RWTH Aachen University, Aachen, Germany
| | - Hans-Georg Schaible
- Institute of Physiology 1/Neurophysiology, University Hospital - Friedrich Schiller University Jena, Jena, Germany
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27
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Autophagy in Neuronal Development and Plasticity. Trends Neurosci 2020; 43:767-779. [PMID: 32800535 DOI: 10.1016/j.tins.2020.07.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 06/03/2020] [Accepted: 07/09/2020] [Indexed: 01/05/2023]
Abstract
Autophagy is a highly conserved intracellular clearance pathway in which cytoplasmic contents are trafficked to the lysosome for degradation. Within neurons, it helps to remove damaged organelles and misfolded or aggregated proteins and has therefore been the subject of intense research in relation to neurodegenerative disease. However, far less is understood about the role of autophagy in other aspects of neuronal physiology. Here we review the literature on the role of autophagy in maintaining neuronal stem cells and in neuronal plasticity in adult life and we discuss how these contribute to structural and functional deficits observed in a range of human disorders.
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28
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Stamatakou E, Wróbel L, Hill SM, Puri C, Son SM, Fujimaki M, Zhu Y, Siddiqi F, Fernandez-Estevez M, Manni MM, Park SJ, Villeneuve J, Rubinsztein DC. Mendelian neurodegenerative disease genes involved in autophagy. Cell Discov 2020; 6:24. [PMID: 32377374 PMCID: PMC7198619 DOI: 10.1038/s41421-020-0158-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 03/11/2020] [Indexed: 12/13/2022] Open
Abstract
The lysosomal degradation pathway of macroautophagy (herein referred to as autophagy) plays a crucial role in cellular physiology by regulating the removal of unwanted cargoes such as protein aggregates and damaged organelles. Over the last five decades, significant progress has been made in understanding the molecular mechanisms that regulate autophagy and its roles in human physiology and diseases. These advances, together with discoveries in human genetics linking autophagy-related gene mutations to specific diseases, provide a better understanding of the mechanisms by which autophagy-dependent pathways can be potentially targeted for treating human diseases. Here, we review mutations that have been identified in genes involved in autophagy and their associations with neurodegenerative diseases.
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Affiliation(s)
- Eleanna Stamatakou
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Lidia Wróbel
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Sandra Malmgren Hill
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Claudia Puri
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Sung Min Son
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Motoki Fujimaki
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Ye Zhu
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Farah Siddiqi
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Marian Fernandez-Estevez
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Marco M. Manni
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - So Jung Park
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - Julien Villeneuve
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
| | - David Chaim Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, CB2 0XY UK
- UK Dementia Research Institute, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY UK
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29
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Breiden B, Sandhoff K. Mechanism of Secondary Ganglioside and Lipid Accumulation in Lysosomal Disease. Int J Mol Sci 2020; 21:ijms21072566. [PMID: 32272755 PMCID: PMC7178057 DOI: 10.3390/ijms21072566] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 03/26/2020] [Accepted: 04/04/2020] [Indexed: 02/06/2023] Open
Abstract
Gangliosidoses are caused by monogenic defects of a specific hydrolase or an ancillary sphingolipid activator protein essential for a specific step in the catabolism of gangliosides. Such defects in lysosomal function cause a primary accumulation of multiple undegradable gangliosides and glycosphingolipids. In reality, however, predominantly small gangliosides also accumulate in many lysosomal diseases as secondary storage material without any known defect in their catabolic pathway. In recent reconstitution experiments, we identified primary storage materials like sphingomyelin, cholesterol, lysosphingolipids, and chondroitin sulfate as strong inhibitors of sphingolipid activator proteins (like GM2 activator protein, saposin A and B), essential for the catabolism of many gangliosides and glycosphingolipids, as well as inhibitors of specific catabolic steps in lysosomal ganglioside catabolism and cholesterol turnover. In particular, they trigger a secondary accumulation of ganglioside GM2, glucosylceramide and cholesterol in Niemann–Pick disease type A and B, and of GM2 and glucosylceramide in Niemann–Pick disease type C. Chondroitin sulfate effectively inhibits GM2 catabolism in mucopolysaccharidoses like Hurler, Hunter, Sanfilippo, and Sly syndrome and causes a secondary neuronal ganglioside GM2 accumulation, triggering neurodegeneration. Secondary ganglioside and lipid accumulation is furthermore known in many more lysosomal storage diseases, so far without known molecular basis.
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30
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Darios F, Stevanin G. Impairment of Lysosome Function and Autophagy in Rare Neurodegenerative Diseases. J Mol Biol 2020; 432:2714-2734. [PMID: 32145221 PMCID: PMC7232018 DOI: 10.1016/j.jmb.2020.02.033] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/28/2020] [Accepted: 02/28/2020] [Indexed: 02/07/2023]
Abstract
Rare genetic diseases affect a limited number of patients, but their etiology is often known, facilitating the development of reliable animal models and giving the opportunity to investigate physiopathology. Lysosomal storage disorders are a group of rare diseases due to primary alteration of lysosome function. These diseases are often associated with neurological symptoms, which highlighted the importance of lysosome in neurodegeneration. Likewise, other groups of rare neurodegenerative diseases also present lysosomal alteration. Lysosomes fuse with autophagosomes and endosomes to allow the degradation of their content thanks to hydrolytic enzymes. It has emerged that alteration of the autophagy–lysosome pathway could play a critical role in neuronal death in many neurodegenerative diseases. Using a repertoire of selected rare neurodegenerative diseases, we highlight that a variety of alterations of the autophagy–lysosome pathway are associated with neuronal death. Yet, in most cases, it is still unclear why alteration of this pathway can lead to neurodegeneration. Lysosome function is impaired in many rare neurodegenerative diseases, making it a convergent point for these diseases. Impaired lysosome function is associated with alteration of the autophagy pathway. Autophagy–lysosome pathway can be impaired at various steps in different rare neurodegenerative diseases. The mechanisms linking impaired autophagy–lysosome pathway to neurodegeneration are still not fully elucidated.
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Affiliation(s)
- Frédéric Darios
- Sorbonne Université, F-75013, Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France.
| | - Giovanni Stevanin
- Sorbonne Université, F-75013, Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle Epinière, ICM, F-75013 Paris, France; PSL Research University, Ecole Pratique des Hautes Etudes, Laboratoire de Neurogénétique, F-75013 Paris, France
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31
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Ivankovic D, Drew J, Lesept F, White IJ, López Doménech G, Tooze SA, Kittler JT. Axonal autophagosome maturation defect through failure of ATG9A sorting underpins pathology in AP-4 deficiency syndrome. Autophagy 2020; 16:391-407. [PMID: 31142229 PMCID: PMC6999640 DOI: 10.1080/15548627.2019.1615302] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 04/02/2019] [Accepted: 04/29/2019] [Indexed: 12/26/2022] Open
Abstract
Adaptor protein (AP) complexes mediate key sorting decisions in the cell through selective incorporation of transmembrane proteins into vesicles. Little is known of the roles of AP-4, despite its loss of function leading to a severe early onset neurological disorder, AP-4 deficiency syndrome. Here we demonstrate an AP-4 epsilon subunit knockout mouse model that recapitulates characteristic neuroanatomical phenotypes of AP-4 deficiency patients. We show that ATG9A, critical for autophagosome biogenesis, is an AP-4 cargo, which is retained within the trans-Golgi network (TGN) in vivo and in culture when AP-4 function is lost. TGN retention results in depletion of axonal ATG9A, leading to defective autophagosome generation and aberrant expansions of the distal axon. The reduction in the capacity to generate axonal autophagosomes leads to defective axonal extension and de novo generation of distal axonal swellings containing accumulated ER, underlying the impaired axonal integrity in AP-4 deficiency syndrome.Abbreviations: AP: adaptor protein; AP4B1: adaptor-related protein complex AP-4, beta 1; AP4E1: adaptor-related protein complex AP-4, epsilon 1; ATG: autophagy-related; EBSS: Earle's balanced salt solution; ER: endoplasmic reticulum; GFAP: glial fibrillary acidic protein; GOLGA1/Golgin-97/GOLG97: golgi autoantigen, golgin subfamily a, 1; GOLGA2/GM130: golgi autoantigen, golgin subfamily a, 2; HSP: hereditary spastic paraplegia; LC3/MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; MAP2: microtubule-associated protein 2; MAPK8IP1/JIP1: mitogen-acitvated protein kinase 8 interacting protein 1; NEFH/NF200: neurofilament, heavy polypeptide; RBFOX3/NeuN (RNA binding protein, fox-1 homolog [C. elegans] 3); SQSTM1/p62: sequestosome 1; TGN: trans-Golgi network; WIPI2: WD repeat domain, phosphoinositide interacting protein 2.
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Affiliation(s)
| | - James Drew
- Neuroscience, Physiology and Pharmacology, UCL, London, UK
| | - Flavie Lesept
- Neuroscience, Physiology and Pharmacology, UCL, London, UK
| | - Ian J. White
- MRC Laboratory for Molecular Cell Biology, UCL, London, UK
| | | | - Sharon A. Tooze
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, London, UK
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32
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Darios F, Mochel F, Stevanin G. Lipids in the Physiopathology of Hereditary Spastic Paraplegias. Front Neurosci 2020; 14:74. [PMID: 32180696 PMCID: PMC7059351 DOI: 10.3389/fnins.2020.00074] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/20/2020] [Indexed: 12/12/2022] Open
Abstract
Hereditary spastic paraplegias (HSP) are a group of neurodegenerative diseases sharing spasticity in lower limbs as common symptom. There is a large clinical variability in the presentation of patients, partly underlined by the large genetic heterogeneity, with more than 60 genes responsible for HSP. Despite this large heterogeneity, the proteins with known function are supposed to be involved in a limited number of cellular compartments such as shaping of the endoplasmic reticulum or endolysosomal function. Yet, it is difficult to understand why alteration of such different cellular compartments can lead to degeneration of the axons of cortical motor neurons. A common feature that has emerged over the last decade is the alteration of lipid metabolism in this group of pathologies. This was first revealed by the identification of mutations in genes encoding proteins that have or are supposed to have enzymatic activities on lipid substrates. However, it also appears that mutations in genes affecting endoplasmic reticulum, mitochondria, or endolysosome function can lead to changes in lipid distribution or metabolism. The aim of this review is to discuss the role of lipid metabolism alterations in the physiopathology of HSP, to evaluate how such alterations contribute to neurodegenerative phenotypes, and to understand how this knowledge can help develop therapeutic strategy for HSP.
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Affiliation(s)
- Frédéric Darios
- Sorbonne Université, Paris, France.,Inserm, U1127, Paris, France.,CNRS, UMR 7225, Paris, France.,Institut du Cerveau et de la Moelle Epinière, Paris, France
| | - Fanny Mochel
- Sorbonne Université, Paris, France.,Inserm, U1127, Paris, France.,CNRS, UMR 7225, Paris, France.,Institut du Cerveau et de la Moelle Epinière, Paris, France.,National Reference Center for Neurometabolic Diseases, Pitié-Salpêtrière University Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Giovanni Stevanin
- Sorbonne Université, Paris, France.,Inserm, U1127, Paris, France.,CNRS, UMR 7225, Paris, France.,Institut du Cerveau et de la Moelle Epinière, Paris, France.,Equipe de Neurogénétique, Ecole Pratique des Hautes Etudes, PSL Research University, Paris, France
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33
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Teinert J, Behne R, Wimmer M, Ebrahimi-Fakhari D. Novel insights into the clinical and molecular spectrum of congenital disorders of autophagy. J Inherit Metab Dis 2020; 43:51-62. [PMID: 30854657 DOI: 10.1002/jimd.12084] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 03/07/2019] [Indexed: 12/24/2022]
Abstract
Autophagy is a fundamental and conserved catabolic pathway that mediates the degradation of macromolecules and organelles in lysosomes. Autophagy is particularly important to postmitotic and metabolically active cells such as neurons. The complex architecture of neurons and their long axons pose additional challenges for efficient recycling of cargo. Not surprisingly autophagy is required for normal central nervous system development and function. Several single-gene disorders of the autophagy pathway have been discovered in recent years giving rise to a novel group of inborn errors of metabolism referred to as congenital disorders of autophagy. While these disorders are heterogeneous, they share several clinical and molecular characteristics including a prominent and progressive involvement of the central nervous system leading to brain malformations, developmental delay, intellectual disability, epilepsy, movement disorders, and cognitive decline. On brain magnetic resonance imaging a predominant involvement of the corpus callosum, the corticospinal tracts and the cerebellum are noted. A storage disease phenotype is present in some diseases, underscoring both clinical and molecular overlaps to lysosomal storage diseases. This review provides an update on the clinical, imaging, and genetic spectrum of congenital disorders of autophagy and highlights the importance of this pathway for neurometabolism and childhood-onset neurological diseases.
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Affiliation(s)
- Julian Teinert
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Robert Behne
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Miriam Wimmer
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Darius Ebrahimi-Fakhari
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
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Volpatti JR, Al-Maawali A, Smith L, Al-Hashim A, Brill JA, Dowling JJ. The expanding spectrum of neurological disorders of phosphoinositide metabolism. Dis Model Mech 2019; 12:12/8/dmm038174. [PMID: 31413155 PMCID: PMC6737944 DOI: 10.1242/dmm.038174] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Phosphoinositides (PIPs) are a ubiquitous group of seven low-abundance phospholipids that play a crucial role in defining localized membrane properties and that regulate myriad cellular processes, including cytoskeletal remodeling, cell signaling cascades, ion channel activity and membrane traffic. PIP homeostasis is tightly regulated by numerous inositol kinases and phosphatases, which phosphorylate and dephosphorylate distinct PIP species. The importance of these phospholipids, and of the enzymes that regulate them, is increasingly being recognized, with the identification of human neurological disorders that are caused by mutations in PIP-modulating enzymes. Genetic disorders of PIP metabolism include forms of epilepsy, neurodegenerative disease, brain malformation syndromes, peripheral neuropathy and congenital myopathy. In this Review, we provide an overview of PIP function and regulation, delineate the disorders associated with mutations in genes that modulate or utilize PIPs, and discuss what is understood about gene function and disease pathogenesis as established through animal models of these diseases. Summary: This Review highlights the intersection between phosphoinositides and the enzymes that regulate their metabolism, which together are crucial regulators of myriad cellular processes and neurological disorders.
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Affiliation(s)
- Jonathan R Volpatti
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Almundher Al-Maawali
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat 123, Oman
| | - Lindsay Smith
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Aqeela Al-Hashim
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada.,Department of Neuroscience, King Fahad Medical City, Riyadh 11525, Saudi Arabia
| | - Julie A Brill
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Program in Cell Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - James J Dowling
- Division of Neurology and Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada .,Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
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35
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Abstract
Protein coats are supramolecular complexes that assemble on the cytosolic face of membranes to promote cargo sorting and transport carrier formation in the endomembrane system of eukaryotic cells. Several types of protein coats have been described, including COPI, COPII, AP-1, AP-2, AP-3, AP-4, AP-5, and retromer, which operate at different stages of the endomembrane system. Defects in these coats impair specific transport pathways, compromising the function and viability of the cells. In humans, mutations in subunits of these coats cause various congenital diseases that are collectively referred to as coatopathies. In this article, we review the fundamental properties of protein coats and the diseases that result from mutation of their constituent subunits.
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Affiliation(s)
- Esteban C Dell'Angelica
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
| | - Juan S Bonifacino
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, Maryland 20892, USA;
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36
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Complexity of Generating Mouse Models to Study the Upper Motor Neurons: Let Us Shift Focus from Mice to Neurons. Int J Mol Sci 2019; 20:ijms20163848. [PMID: 31394733 PMCID: PMC6720674 DOI: 10.3390/ijms20163848] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 07/26/2019] [Accepted: 08/05/2019] [Indexed: 12/11/2022] Open
Abstract
Motor neuron circuitry is one of the most elaborate circuitries in our body, which ensures voluntary and skilled movement that requires cognitive input. Therefore, both the cortex and the spinal cord are involved. The cortex has special importance for motor neuron diseases, in which initiation and modulation of voluntary movement is affected. Amyotrophic lateral sclerosis (ALS) is defined by the progressive degeneration of both the upper and lower motor neurons, whereas hereditary spastic paraplegia (HSP) and primary lateral sclerosis (PLS) are characterized mainly by the loss of upper motor neurons. In an effort to reveal the cellular and molecular basis of neuronal degeneration, numerous model systems are generated, and mouse models are no exception. However, there are many different levels of complexities that need to be considered when developing mouse models. Here, we focus our attention to the upper motor neurons, which are one of the most challenging neuron populations to study. Since mice and human differ greatly at a species level, but the cells/neurons in mice and human share many common aspects of cell biology, we offer a solution by focusing our attention to the affected neurons to reveal the complexities of diseases at a cellular level and to improve translational efforts.
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Newton T, Allison R, Edgar JR, Lumb JH, Rodger CE, Manna PT, Rizo T, Kohl Z, Nygren AOH, Arning L, Schüle R, Depienne C, Goldberg L, Frahm C, Stevanin G, Durr A, Schöls L, Winner B, Beetz C, Reid E. Mechanistic basis of an epistatic interaction reducing age at onset in hereditary spastic paraplegia. Brain 2019; 141:1286-1299. [PMID: 29481671 PMCID: PMC5917785 DOI: 10.1093/brain/awy034] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 01/04/2018] [Indexed: 12/20/2022] Open
Abstract
Many genetic neurological disorders exhibit variable expression within affected families, often exemplified by variations in disease age at onset. Epistatic effects (i.e. effects of modifier genes on the disease gene) may underlie this variation, but the mechanistic basis for such epistatic interactions is rarely understood. Here we report a novel epistatic interaction between SPAST and the contiguous gene DPY30, which modifies age at onset in hereditary spastic paraplegia, a genetic axonopathy. We found that patients with hereditary spastic paraplegia caused by genomic deletions of SPAST that extended into DPY30 had a significantly younger age at onset. We show that, like spastin, the protein encoded by SPAST, the DPY30 protein controls endosomal tubule fission, traffic of mannose 6-phosphate receptors from endosomes to the Golgi, and lysosomal ultrastructural morphology. We propose that additive effects on this pathway explain the reduced age at onset of hereditary spastic paraplegia in patients who are haploinsufficient for both genes.
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Affiliation(s)
- Timothy Newton
- Department of Medical Genetics and Cambridge Institute for Medical Research, University of Cambridge, UK
| | - Rachel Allison
- Department of Medical Genetics and Cambridge Institute for Medical Research, University of Cambridge, UK
| | - James R Edgar
- Department of Clinical Biochemistry and Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Jennifer H Lumb
- Department of Medical Genetics and Cambridge Institute for Medical Research, University of Cambridge, UK
| | - Catherine E Rodger
- Department of Medical Genetics and Cambridge Institute for Medical Research, University of Cambridge, UK
| | - Paul T Manna
- Department of Clinical Biochemistry and Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Tania Rizo
- Department of Stem Cell Biology, Friedrich-Alexander University Erlangen-Nuernberg (FAU), Erlangen, Germany
| | - Zacharias Kohl
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nuernberg (FAU), Erlangen, Germany
| | | | - Larissa Arning
- Department of Human Genetics, Ruhr-University, Bochum, Germany
| | - Rebecca Schüle
- Center for Neurology and Hertie Institute for Clinical Brain Research, Eberhard-Karls-University, 72076 Tübingen, Germany.,German Center of Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany
| | - Christel Depienne
- ICM Brain and Spine Institute, INSERM U1127, CNRS UMR7225, Sorbonne Universites, UPMC Univ Paris VI UMR_S1127, Paris, France.,APHP, Genetic Department, Pitie-Salpêtrière University Hospital, Paris, France
| | - Lisa Goldberg
- Department of Clinical Chemistry and Laboratory Diagnostics, Jena University Hospital, Jena, Germany
| | - Christiane Frahm
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Giovanni Stevanin
- ICM Brain and Spine Institute, INSERM U1127, CNRS UMR7225, Sorbonne Universites, UPMC Univ Paris VI UMR_S1127, Paris, France.,APHP, Genetic Department, Pitie-Salpêtrière University Hospital, Paris, France.,Ecole Pratique des Hautes Etudes, PSL Research University, Paris, France
| | - Alexandra Durr
- ICM Brain and Spine Institute, INSERM U1127, CNRS UMR7225, Sorbonne Universites, UPMC Univ Paris VI UMR_S1127, Paris, France.,APHP, Genetic Department, Pitie-Salpêtrière University Hospital, Paris, France
| | - Ludger Schöls
- Center for Neurology and Hertie Institute for Clinical Brain Research, Eberhard-Karls-University, 72076 Tübingen, Germany.,German Center of Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany
| | - Beate Winner
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nuernberg (FAU), Erlangen, Germany
| | - Christian Beetz
- Department of Clinical Chemistry and Laboratory Diagnostics, Jena University Hospital, Jena, Germany
| | - Evan Reid
- Department of Medical Genetics and Cambridge Institute for Medical Research, University of Cambridge, UK
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38
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Saffi GT, Botelho RJ. Lysosome Fission: Planning for an Exit. Trends Cell Biol 2019; 29:635-646. [PMID: 31171420 DOI: 10.1016/j.tcb.2019.05.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/01/2019] [Accepted: 05/03/2019] [Indexed: 01/26/2023]
Abstract
Lysosomes are acidic and degradative organelles that receive and digest a plethora of molecular and particulate cargo delivered by endocytosis, autophagy, and phagocytosis. The mechanisms responsible for sorting, transporting, and ultimately delivering membranes and cargo to lysosomes through fusion have been intensely investigated. Much less is understood about lysosome fission, which is necessary to balance the incessant flow of cargo into lysosomes and maintain steady-state number, size, and function of lysosomes. Here, we review the emerging picture of how lipid signals, coat and adaptor proteins, and motor-cytoskeletal assemblies drive budding, tubulation, splitting, and 'kiss-and-run' events that enable fission and exit from lysosomes and related organelles.
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Affiliation(s)
- Golam T Saffi
- Department of Chemistry and Biology and the Molecular Science Graduate Program, Ryerson University, Toronto, ONT, M5B2K3, Canada
| | - Roberto J Botelho
- Department of Chemistry and Biology and the Molecular Science Graduate Program, Ryerson University, Toronto, ONT, M5B2K3, Canada.
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Khundadze M, Ribaudo F, Hussain A, Rosentreter J, Nietzsche S, Thelen M, Winter D, Hoffmann B, Afzal MA, Hermann T, de Heus C, Piskor EM, Kosan C, Franzka P, von Kleist L, Stauber T, Klumperman J, Damme M, Proikas-Cezanne T, Hübner CA. A mouse model for SPG48 reveals a block of autophagic flux upon disruption of adaptor protein complex five. Neurobiol Dis 2019; 127:419-431. [PMID: 30930081 DOI: 10.1016/j.nbd.2019.03.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 02/25/2019] [Accepted: 03/24/2019] [Indexed: 12/25/2022] Open
Abstract
Hereditary spastic paraplegia is a spastic gait disorder that arises from degeneration of corticospinal axons. The subtype SPG48 is associated with mutations in the zeta subunit of the adaptor protein complex five (AP5). AP5 function and the pathophysiology of SPG48 are only poorly understood. Here, we report an AP5 zeta knockout mouse, which shows an age-dependent degeneration of corticospinal axons. Our analysis of knockout fibroblasts supports a trafficking defect from late endosomes to the transGolgi network and reveals a structural defect of the Golgi. We further show that both autophagic flux and the recycling of lysosomes from autolysosomes were impaired in knockout cells. In vivo, we observe an increase of autophagosomes and autolysosomes and, at later stages, the accumulation of intracellular waste in neurons. Taken together, we propose that loss of AP5 function blocks autophagy and thus leads to the aberrant accumulation of autophagic cargo, which finally results in axon degeneration.
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Affiliation(s)
- Mukhran Khundadze
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany.
| | - Federico Ribaudo
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany
| | - Adeela Hussain
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany
| | - Jan Rosentreter
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany
| | - Sandor Nietzsche
- Electron Microscopy Center, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07743, Germany
| | - Melanie Thelen
- Institute for Biochemistry and Molecular Biology, University of Bonn, Bonn 53115, Germany
| | - Dominic Winter
- Institute for Biochemistry and Molecular Biology, University of Bonn, Bonn 53115, Germany
| | - Birgit Hoffmann
- Biomolecular Photonics Group, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07743, Germany
| | - Muhammad Awais Afzal
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany
| | - Tanja Hermann
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany
| | - Cecilia de Heus
- Department of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht 3584, Netherlands
| | - Eva-Maria Piskor
- Institute of Biochemistry and Biophysics, Friedrich-Schiller-University Jena, Jena 07743, Germany
| | - Christian Kosan
- Institute of Biochemistry and Biophysics, Friedrich-Schiller-University Jena, Jena 07743, Germany
| | - Patricia Franzka
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany
| | - Lisa von Kleist
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin 14195, Germany
| | - Tobias Stauber
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin 14195, Germany
| | - Judith Klumperman
- Department of Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht 3584, Netherlands
| | - Markus Damme
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel 24118, Germany
| | - Tassula Proikas-Cezanne
- Department of Molecular Biology, Eberhard Karls University Tübingen, Tübingen 72076, Germany
| | - Christian A Hübner
- Institute of Human Genetics, University Hospital Jena, Friedrich-Schiller-University Jena, Jena 07747, Germany.
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40
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Denton K, Mou Y, Xu CC, Shah D, Chang J, Blackstone C, Li XJ. Impaired mitochondrial dynamics underlie axonal defects in hereditary spastic paraplegias. Hum Mol Genet 2019; 27:2517-2530. [PMID: 29726929 DOI: 10.1093/hmg/ddy156] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 04/25/2018] [Indexed: 01/01/2023] Open
Abstract
Mechanisms by which long corticospinal axons degenerate in hereditary spastic paraplegia (HSP) are largely unknown. Here, we have generated induced pluripotent stem cells (iPSCs) from patients with two autosomal recessive forms of HSP, SPG15 and SPG48, which are caused by mutations in the ZFYVE26 and AP5Z1 genes encoding proteins in the same complex, the spastizin and AP5Z1 proteins, respectively. In patient iPSC-derived telencephalic glutamatergic and midbrain dopaminergic neurons, neurite number, length and branching are significantly reduced, recapitulating disease-specific phenotypes. We analyzed mitochondrial morphology and noted a significant reduction in both mitochondrial length and their densities within axons of these HSP neurons. Mitochondrial membrane potential was also decreased, confirming functional mitochondrial defects. Notably, mdivi-1, an inhibitor of the mitochondrial fission GTPase DRP1, rescues mitochondrial morphology defects and suppresses the impairment in neurite outgrowth and late-onset apoptosis in HSP neurons. Furthermore, knockdown of these HSP genes causes similar axonal defects, also mitigated by treatment with mdivi-1. Finally, neurite outgrowth defects in SPG15 and SPG48 cortical neurons can be rescued by knocking down DRP1 directly. Thus, abnormal mitochondrial morphology caused by an imbalance of mitochondrial fission and fusion underlies specific axonal defects and serves as a potential therapeutic target for SPG15 and SPG48.
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Affiliation(s)
- Kyle Denton
- Department of Neuroscience, University of Connecticut Health Center, Farmington, CT, USA
| | - Yongchao Mou
- Department of Biomedical Sciences, University of Illinois College of Medicine at Rockford, Rockford, IL, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Chong-Chong Xu
- Department of Biomedical Sciences, University of Illinois College of Medicine at Rockford, Rockford, IL, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Dhruvi Shah
- Department of Biomedical Sciences, University of Illinois College of Medicine at Rockford, Rockford, IL, USA
| | - Jaerak Chang
- Cell Biology Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.,Departments of Biomedical Science, Brain Science, and Neuroscience Graduate Program, Ajou University School of Medicine, Suwon, Korea
| | - Craig Blackstone
- Cell Biology Section, Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Xue-Jun Li
- Department of Biomedical Sciences, University of Illinois College of Medicine at Rockford, Rockford, IL, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
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41
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Boutry M, Morais S, Stevanin G. Update on the Genetics of Spastic Paraplegias. Curr Neurol Neurosci Rep 2019; 19:18. [DOI: 10.1007/s11910-019-0930-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Trummer B, Haubenberger D, Blackstone C. Clinical Trial Designs and Measures in Hereditary Spastic Paraplegias. Front Neurol 2018; 9:1017. [PMID: 30627115 PMCID: PMC6309810 DOI: 10.3389/fneur.2018.01017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 11/12/2018] [Indexed: 01/19/2023] Open
Abstract
Hereditary spastic paraplegias (HSPs) are a large group of genetically-diverse neurologic disorders characterized clinically by a common feature of lower extremity spasticity and gait difficulties. Current therapies are predominantly symptomatic, and even then usually provide inadequate relief of symptoms. Going forward, HSP therapeutics development requires a systematic analysis of quantifiable measures and tools to assess treatment response. This review summarizes promising therapeutic targets, assessment measures, and previous clinical trials for the HSPs. Oxidative stress, signaling pathways, microtubule dynamics, and gene rescue/replacement have been proposed as potential treatment targets or modalities. Quantitative evaluation of pre-clinical rodent HSP models emphasize rotarod performance, foot base angle, grip strength, stride length, beam walking, critical speed, and body weight. Clinical measures of HSP in humans include 10-m gait velocity, the Spastic Paraplegia Rating Scale (SPRS), Ashworth Spasticity Scale, Fugl-Meyer Scale, timed up-and-go, and the Gillette Functional Assessment Questionnaire. We conducted a broad search for past clinical trials in HSPs and identified trials that investigated pharmacological agents including atorvastatin, gabapentin, L-threonine, botulinum toxin, dalfampridine, methylphenidate, and baclofen. We provide recommendations for future HSP treatment directions based on these prior research experiences as well as regulatory insight.
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Affiliation(s)
- Brian Trummer
- Neurogenetics Branch, Clinical Research Program, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
- Clinical Trials Unit, Clinical Research Program, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Dietrich Haubenberger
- Clinical Trials Unit, Clinical Research Program, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Craig Blackstone
- Neurogenetics Branch, Clinical Research Program, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
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Vinci M, Fchera M, Antonino Musumeci S, Cali F, Aurelio Vitello G. Novel c.C2254T (p.Q752*) mutation in ZFYVE26 (SPG15) gene in a patient with hereditary spastic paraparesis. J Genet 2018; 97:1469-1472. [PMID: 30555096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Hereditary spastic paraplegias are clinically and genetically heterogeneous degenerative disorders, and pathological variants in the autosomal recessive ZFYVE26 gene are considered as very rare causes. We describe a novel mutation in ZFYVE26 gene found in a patient with autosomal recessive spastic paraplegias. The use of a 'target-gene' approach allowed us to expand the clinical spectrum associated with hereditary spastic paraplegias.
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Vinci M, Fichera M, Musumeci SA, Cali F, Vitello GA. Novel c.C2254T (p.Q752*) mutation in ZFYVE26 (SPG15) gene in a patient with hereditary spastic paraparesis. J Genet 2018. [DOI: 10.1007/s12041-018-1038-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Vantaggiato C, Panzeri E, Castelli M, Citterio A, Arnoldi A, Santorelli FM, Liguori R, Scarlato M, Musumeci O, Toscano A, Clementi E, Bassi MT. ZFYVE26/SPASTIZIN and SPG11/SPATACSIN mutations in hereditary spastic paraplegia types AR-SPG15 and AR-SPG11 have different effects on autophagy and endocytosis. Autophagy 2018; 15:34-57. [PMID: 30081747 DOI: 10.1080/15548627.2018.1507438] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
ZFYVE26/Spastizin and SPG11/Spatacsin encode 2 large proteins that are mutated in hereditary autosomal-recessive spastic paraplegia/paraparesis (HSP) type 15 (AR-SPG15) and type 11 (AR-SPG11), respectively. We previously have reported that AR-SPG15-related ZFYVE26 mutations lead to autophagy defects with accumulation of immature autophagosomes. ZFYVE26 and SPG11 were found to be part of a complex including the AP5 (adaptor related protein complex 5) and to have a critical role in autophagic lysosomal reformation with identification of autophagic and lysosomal defects in cells with both AR-SPG15- and AR-SPG11-related mutations. In spite of these similarities between the 2 proteins, here we report that ZFYVE26 and SPG11 are differently involved in autophagy and endocytosis. We found that both ZFYVE26 and SPG11 interact with RAB5A and RAB11, 2 proteins regulating endosome trafficking and maturation, but only ZFYVE26 mutations affected RAB protein interactions and activation. ZFYVE26 mutations lead to defects in the fusion between autophagosomes and endosomes, while SPG11 mutations do not affect this step and lead to a milder autophagy defect. We thus demonstrate that ZFYVE26 and SPG11 affect the same cellular physiological processes, albeit at different levels: both proteins have a role in autophagic lysosome reformation, but only ZFYVE26 acts at the intersection between endocytosis and autophagy, thus representing a key player in these 2 processes. Indeed expression of the constitutively active form of RAB5A in cells with AR-SPG15-related mutations partially rescues the autophagy defect. Finally the model we propose demonstrates that autophagy and the endolysosomal pathway are central processes in the pathogenesis of these complicated forms of hereditary spastic paraparesis. Abbreviations: ALR, autophagic lysosome reformation; AP5, adaptor related protein complex 5; AR, autosomal-recessive; HSP, hereditary spastic paraplegia/paraparesis; ATG14, autophagy related 14; BafA, bafilomycin A1; BECN1, beclin 1; EBSS, Earle balanced salt solution; EEA1, early endosome antigen 1; EGF, epidermal growth factor; EGFR, epidermal growth factor receptor; GDP, guanosine diphosphate; GFP, green fluorescent protein; GTP, guanosine triphosphate; HSP, hereditary spastic paraplegias; LBPA, lysobisphosphatidic acid; MAP1LC3B/LC3B, microtubule associated protein 1 light chain 3 beta; MVBs, multivesicular bodies; PIK3C3, phosphatidylinositol 3-kinase, catalytic subunit type 3; PIK3R4, phosphoinositide-3-kinase regulatory subunit 4; PtdIns3P, phosphatidylinositol-3-phosphate; RFP, red fluorescent protein; RUBCN, RUN and cysteine rich domain containing beclin 1 interacting protein; shRNA, short hairpin RNA; SQSTM1/p62, sequestosome 1; TCC: thin corpus callosum; TF, transferrin; UVRAG, UV radiation resistance associated.
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Affiliation(s)
- Chiara Vantaggiato
- a Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology , Bosisio Parini , Lecco , Italy
| | - Elena Panzeri
- a Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology , Bosisio Parini , Lecco , Italy
| | - Marianna Castelli
- a Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology , Bosisio Parini , Lecco , Italy
| | - Andrea Citterio
- a Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology , Bosisio Parini , Lecco , Italy
| | - Alessia Arnoldi
- a Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology , Bosisio Parini , Lecco , Italy
| | | | - Rocco Liguori
- c Department of Biomedical and Neuromotor Sciences , University of Bologna; IRCCS Institute of Neurological Sciences , Bologna , Italy
| | - Marina Scarlato
- d Dept. of Neurosciences and Institute of Experimental Neurology (INSpe) , San Raffaele Scientific Institute , Milan , Italy
| | - Olimpia Musumeci
- e Department of Clinical and Experimental Medicine , University of Messina , Messina , Italy
| | - Antonio Toscano
- e Department of Clinical and Experimental Medicine , University of Messina , Messina , Italy
| | - Emilio Clementi
- a Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology , Bosisio Parini , Lecco , Italy.,f Unit of Clinical Pharmacology, CNR Institute of Neuroscience, Department of Biomedical and Clinical Sciences , University Hospital "Luigi Sacco", Università di Milano , Milan , Italy
| | - Maria Teresa Bassi
- a Scientific Institute, IRCCS E. Medea, Laboratory of Molecular Biology , Bosisio Parini , Lecco , Italy
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Beetz C, Khundadze M, Goldberg LV, Hübner CA. Erbliche spastische Spinalparalysen: aktuelle Erkenntnisse und Entwicklungen. MED GENET-BERLIN 2018. [DOI: 10.1007/s11825-018-0196-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Zusammenfassung
Die erblichen spastischen Spinalparalysen („hereditary spastic paraplegias“, HSPs) sind Bewegungsstörungen, die aus der Degeneration der Axone oberer Motoneuronen resultieren. Sie sind klinisch und genetisch sehr heterogen. Der vorliegende Übersichtsartikel fasst aktuelle Strategien zur genetischen Diagnostik der HSPs zusammen, erörtert mögliche Mutationsmechanismen, diskutiert Erklärungen für die klinische Variabilität innerhalb ausgewählter Formen und verweist auf noch ungeklärte und zum Teil wenig beachtete Phänomene. Außerdem wird die Notwendigkeit eines tieferen Verständnisses der zellulären und molekularen Mechanismen für die Entwicklung neuer Therapien dargestellt.
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Affiliation(s)
- Christian Beetz
- Aff1 0000 0000 8517 6224 grid.275559.9 Institut für Klinische Chemie und Laboratoriumsdiagnostik Universitätsklinikum Jena Jena Deutschland
| | - Mukhran Khundadze
- Aff2 0000 0000 8517 6224 grid.275559.9 Institut für Humangenetik Universitätsklinikum Jena Am Klinikum 1 07747 Jena Deutschland
| | - Lisa V. Goldberg
- Aff1 0000 0000 8517 6224 grid.275559.9 Institut für Klinische Chemie und Laboratoriumsdiagnostik Universitätsklinikum Jena Jena Deutschland
| | - Christian A. Hübner
- Aff2 0000 0000 8517 6224 grid.275559.9 Institut für Humangenetik Universitätsklinikum Jena Am Klinikum 1 07747 Jena Deutschland
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Abstract
Lysosomes support diverse cellular functions by acting as sites of macromolecule degradation and nutrient recycling. The degradative abilities of lysosomes are conferred by a lumen that is characterized by an acidic pH and which contains numerous hydrolases that support the breakdown of major cellular macromolecules to yield cellular building blocks (amino acids, nucleic acids, sugars, lipids and metals) that are transported into the cytoplasm for their re-use. In addition to these important hydrolytic and recycling functions, lysosomes also serve as a signaling platform that integrates nutrient and metabolic cues to control signaling via the mTORC1 pathway. Due to their extreme longevity, polarity, demands of neurotransmission and metabolic activity, neurons are particularly sensitive to perturbations in lysosome function. The dependence of neurons on optimal lysosome function is highlighted by insights from human genetics that link lysosome dysfunction to a wide range of both rare and common neurological diseases. How then is lysosome function adapted to the unique demands of neurons? This review will focus on the roles played by lysosomes in distinct neuronal sub-compartments, the regulation of neuronal lysosome sub-cellular localization and the implications of such neuronal lysosome regulation for both physiology and disease.
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Affiliation(s)
- Shawn M Ferguson
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, 06510, United States; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, 06510, United States.
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48
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Role of the AP-5 adaptor protein complex in late endosome-to-Golgi retrieval. PLoS Biol 2018; 16:e2004411. [PMID: 29381698 PMCID: PMC5806898 DOI: 10.1371/journal.pbio.2004411] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 02/09/2018] [Accepted: 01/12/2018] [Indexed: 01/17/2023] Open
Abstract
The AP-5 adaptor protein complex is presumed to function in membrane traffic, but so far nothing is known about its pathway or its cargo. We have used CRISPR-Cas9 to knock out the AP-5 ζ subunit gene, AP5Z1, in HeLa cells, and then analysed the phenotype by subcellular fractionation profiling and quantitative mass spectrometry. The retromer complex had an altered steady-state distribution in the knockout cells, and several Golgi proteins, including GOLIM4 and GOLM1, were depleted from vesicle-enriched fractions. Immunolocalisation showed that loss of AP-5 led to impaired retrieval of the cation-independent mannose 6-phosphate receptor (CIMPR), GOLIM4, and GOLM1 from endosomes back to the Golgi region. Knocking down the retromer complex exacerbated this phenotype. Both the CIMPR and sortilin interacted with the AP-5–associated protein SPG15 in pull-down assays, and we propose that sortilin may act as a link between Golgi proteins and the AP-5/SPG11/SPG15 complex. Together, our findings suggest that AP-5 functions in a novel sorting step out of late endosomes, acting as a backup pathway for retromer. This provides a mechanistic explanation for why mutations in AP-5/SPG11/SPG15 cause cells to accumulate aberrant endolysosomes, and highlights the role of endosome/lysosome dysfunction in the pathology of hereditary spastic paraplegia and other neurodegenerative disorders. Eukaryotic cells contain multiple membrane-bound compartments, each with a distinct function and molecular composition. Proteins are transported from one compartment to another by vesicular carriers. Formation of these carriers requires coat proteins, which both shape the membrane into a vesicle and select the proteins that are to be included as cargo. In many cases, cargo selection is facilitated by an adaptor protein (AP) complex, of which 5 have been identified. The most recently identified complex, AP-5, localises to a late endosomal/lysosomal compartment, and patients with mutations in AP-5 have a form of hereditary spastic paraplegia characterised by aberrant lysosomes. However, the precise function of AP-5, including its cargo and its pathway, has until now been unclear. In the present study, we have used unbiased subcellular proteomics to look for changes in the localisation of thousands of different proteins in cells from which AP-5 has been deleted by gene editing. We found that there are defects in the retrieval of several proteins from late endosomes back to the Golgi apparatus. Thus, we propose that AP-5 facilitates a novel late-acting retrieval pathway, which contributes to normal lysosomal homeostasis.
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49
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Allison R, Edgar JR, Pearson G, Rizo T, Newton T, Günther S, Berner F, Hague J, Connell JW, Winkler J, Lippincott-Schwartz J, Beetz C, Winner B, Reid E. Defects in ER-endosome contacts impact lysosome function in hereditary spastic paraplegia. J Cell Biol 2017; 216:1337-1355. [PMID: 28389476 PMCID: PMC5412567 DOI: 10.1083/jcb.201609033] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 01/20/2017] [Accepted: 02/21/2017] [Indexed: 01/29/2023] Open
Abstract
Hereditary spastic paraplegia (HSP) is a genetically heterogeneous disease caused by mutations in many genes, including those encoding spastin, strumpellin, or REEP1. Allison et al. show that similar lysosomal phenotypes are associated with mutations in different classes of HSP proteins and suggest that defective ER–endosome contacts and endosome tubule fission may be a common cause of axon degeneration in the disease. Contacts between endosomes and the endoplasmic reticulum (ER) promote endosomal tubule fission, but the mechanisms involved and consequences of tubule fission failure are incompletely understood. We found that interaction between the microtubule-severing enzyme spastin and the ESCRT protein IST1 at ER–endosome contacts drives endosomal tubule fission. Failure of fission caused defective sorting of mannose 6-phosphate receptor, with consequently disrupted lysosomal enzyme trafficking and abnormal lysosomal morphology, including in mouse primary neurons and human stem cell–derived neurons. Consistent with a role for ER-mediated endosomal tubule fission in lysosome function, similar lysosomal abnormalities were seen in cellular models lacking the WASH complex component strumpellin or the ER morphogen REEP1. Mutations in spastin, strumpellin, or REEP1 cause hereditary spastic paraplegia (HSP), a disease characterized by axonal degeneration. Our results implicate failure of the ER–endosome contact process in axonopathy and suggest that coupling of ER-mediated endosomal tubule fission to lysosome function links different classes of HSP proteins, previously considered functionally distinct, into a unifying pathway for axonal degeneration.
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Affiliation(s)
- Rachel Allison
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK.,Department of Medical Genetics, University of Cambridge, Cambridge CB2 0XY, England, UK
| | - James R Edgar
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK.,Department of Clinical Biochemistry, University of Cambridge, Cambridge CB2 0XY, England, UK
| | - Guy Pearson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK.,Department of Medical Genetics, University of Cambridge, Cambridge CB2 0XY, England, UK
| | - Tania Rizo
- Interdisciplinary Center for Clinical Research (IZKF) Junior Research Group III and Federal Ministry of Education and Research (BMBF) Research Group Neuroscience, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
| | - Timothy Newton
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK.,Department of Medical Genetics, University of Cambridge, Cambridge CB2 0XY, England, UK
| | - Sven Günther
- Department of Clinical Chemistry and Laboratory Diagnostics, Jena University Hospital, 07743 Jena, Germany
| | - Fiamma Berner
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK
| | - Jennifer Hague
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK.,Department of Medical Genetics, University of Cambridge, Cambridge CB2 0XY, England, UK
| | - James W Connell
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK.,Department of Medical Genetics, University of Cambridge, Cambridge CB2 0XY, England, UK
| | - Jürgen Winkler
- Department of Molecular Neurology, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
| | | | - Christian Beetz
- Department of Clinical Chemistry and Laboratory Diagnostics, Jena University Hospital, 07743 Jena, Germany
| | - Beate Winner
- Interdisciplinary Center for Clinical Research (IZKF) Junior Research Group III and Federal Ministry of Education and Research (BMBF) Research Group Neuroscience, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany.,Institute of Human Genetics, Friedrich-Alexander-University Erlangen-Nuernberg, 91054 Erlangen, Germany
| | - Evan Reid
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, England, UK .,Department of Medical Genetics, University of Cambridge, Cambridge CB2 0XY, England, UK
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50
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Branchu J, Boutry M, Sourd L, Depp M, Leone C, Corriger A, Vallucci M, Esteves T, Matusiak R, Dumont M, Muriel MP, Santorelli FM, Brice A, El Hachimi KH, Stevanin G, Darios F. Loss of spatacsin function alters lysosomal lipid clearance leading to upper and lower motor neuron degeneration. Neurobiol Dis 2017; 102:21-37. [PMID: 28237315 PMCID: PMC5391847 DOI: 10.1016/j.nbd.2017.02.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/10/2017] [Accepted: 02/20/2017] [Indexed: 12/12/2022] Open
Abstract
Mutations in SPG11 account for the most common form of autosomal recessive hereditary spastic paraplegia (HSP), characterized by a gait disorder associated with various brain alterations. Mutations in the same gene are also responsible for rare forms of Charcot-Marie-Tooth (CMT) disease and progressive juvenile-onset amyotrophic lateral sclerosis (ALS). To elucidate the physiopathological mechanisms underlying these human pathologies, we disrupted the Spg11 gene in mice by inserting stop codons in exon 32, mimicking the most frequent mutations found in patients. The Spg11 knockout mouse developed early-onset motor impairment and cognitive deficits. These behavioral deficits were associated with progressive brain atrophy with the loss of neurons in the primary motor cortex, cerebellum and hippocampus, as well as with accumulation of dystrophic axons in the corticospinal tract. Spinal motor neurons also degenerated and this was accompanied by fragmentation of neuromuscular junctions and muscle atrophy. This new Spg11 knockout mouse therefore recapitulates the full range of symptoms associated with SPG11 mutations observed in HSP, ALS and CMT patients. Examination of the cellular alterations observed in this model suggests that the loss of spatacsin leads to the accumulation of lipids in lysosomes by perturbing their clearance from these organelles. Altogether, our results link lysosomal dysfunction and lipid metabolism to neurodegeneration and pinpoint a critical role of spatacsin in lipid turnover. Spg11 knockout mouse recapitulates the motor and cognitive symptoms observed in patients. Spg11 knockout mouse presents neurodegeneration in cortex, cerebellum, hippocampus and spinal cord. Loss of spatacsin, the product of Spg11, leads to early lysosomal dysfunction. Loss of spatacsin promotes lipid accumulation in lysosomes.
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Affiliation(s)
- Julien Branchu
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Maxime Boutry
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Laura Sourd
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Marine Depp
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Céline Leone
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Alexandrine Corriger
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Maeva Vallucci
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Typhaine Esteves
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Raphaël Matusiak
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Magali Dumont
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Marie-Paule Muriel
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Filippo M Santorelli
- Molecular Medicine, IRCCS Stella Maris Foundation, Calambronne, I-56100 Pisa, Italy
| | - Alexis Brice
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Khalid Hamid El Hachimi
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France
| | - Giovanni Stevanin
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Ecole Pratique des Hautes Etudes, PSL Research University, Laboratoire de Neurogénétique, F-75013 Paris, France.
| | - Frédéric Darios
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Inserm, U1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France.
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