1
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D'Souza Z, Pokrovskaya I, Lupashin VV. Syntaxin-5's flexibility in SNARE pairing supports Golgi functions. Traffic 2023; 24:355-379. [PMID: 37340984 PMCID: PMC10330844 DOI: 10.1111/tra.12903] [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: 03/07/2023] [Revised: 05/23/2023] [Accepted: 06/02/2023] [Indexed: 06/22/2023]
Abstract
Deficiency in the conserved oligomeric Golgi (COG) complex that orchestrates SNARE-mediated tethering/fusion of vesicles that recycle the Golgi's glycosylation machinery results in severe glycosylation defects. Although two major Golgi v-SNAREs, GS28/GOSR1, and GS15/BET1L, are depleted in COG-deficient cells, the complete knockout of GS28 and GS15 only modestly affects Golgi glycosylation, indicating the existence of an adaptation mechanism in Golgi SNARE. Indeed, quantitative mass-spectrometry analysis of STX5-interacting proteins revealed two novel Golgi SNARE complexes-STX5/SNAP29/VAMP7 and STX5/VTI1B/STX8/YKT6. These complexes are present in wild-type cells, but their usage is significantly increased in both GS28- and COG-deficient cells. Upon GS28 deletion, SNAP29 increased its Golgi residency in a STX5-dependent manner. While STX5 depletion and Retro2-induced diversion from the Golgi severely affect protein glycosylation, GS28/SNAP29 and GS28/VTI1B double knockouts alter glycosylation similarly to GS28 KO, indicating that a single STX5-based SNARE complex is sufficient to support Golgi glycosylation. Importantly, co-depletion of three Golgi SNARE complexes in GS28/SNAP29/VTI1B TKO cells resulted in severe glycosylation defects and a reduced capacity for glycosylation enzyme retention at the Golgi. This study demonstrates the remarkable plasticity in SXT5-mediated membrane trafficking, uncovering a novel adaptive response to the failure of canonical intra-Golgi vesicle tethering/fusion machinery.
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Affiliation(s)
- Zinia D'Souza
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Irina Pokrovskaya
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Vladimir V Lupashin
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
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2
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Hessvik NP, Sagini K, Romero S, Ramirez-Garrastacho M, Rodriguez M, Tutturen AEV, Kvalvaag A, Stang E, Brech A, Sandvig K, Llorente A. siRNA screening reveals that SNAP29 contributes to exosome release. Cell Mol Life Sci 2023; 80:177. [PMID: 37285022 DOI: 10.1007/s00018-023-04822-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 05/22/2023] [Accepted: 05/23/2023] [Indexed: 06/08/2023]
Abstract
Cells release extracellular vesicles (EVs) of different sizes. Small EVs (< 200 nm) can originate from the fusion of multivesicular bodies with the plasma membrane, i.e. exosomes, and from budding of the plasma membrane, i.e. small ectosomes. To investigate the molecular machinery required for the release of small EVs, we developed a sensitive assay based on incorporation of radioactive cholesterol in EV membranes and used it in a siRNA screening. The screening showed that depletion of several SNARE proteins affected the release of small EVs. We focused on SNAP29, VAMP8, syntaxin 2, syntaxin 3 and syntaxin 18, the depletion of which reduced the release of small EVs. Importantly, this result was verified using gold standard techniques. SNAP29 depletion resulted in the largest effect and was further investigated. Immunoblotting analysis of small EVs showed that the release of several proteins considered to be associated with exosomes like syntenin, CD63 and Tsg101 was reduced, while the level of several proteins that have been shown to be released in ectosomes (annexins) or by secretory autophagy (LC3B and p62) was not affected by SNAP29 depletion. Moreover, these proteins appeared in different fractions when the EV samples were further separated by a density gradient. These results suggest that SNAP29 depletion mainly affects the secretion of exosomes. To investigate how SNAP29 affects exosome release, we used microscopy to study the distribution of MBVs using CD63 labelling and CD63-pHluorin to detect fusion events of MVBs with the plasma membrane. SNAP29 depletion caused a redistribution of CD63-labelled compartments but did not change the number of fusion events. Further experiments are therefore needed to fully understand the function of SNAP29. To conclude, we have developed a novel screening assay that has allowed us to identify several SNAREs involved in the release of small EVs.
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Affiliation(s)
- Nina Pettersen Hessvik
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Krizia Sagini
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Silvana Romero
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Manuel Ramirez-Garrastacho
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Marta Rodriguez
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Pathology Department, IIS-Fundación Jiménez Díaz-UAM, Center for the Biomedical Research Network in Oncology, CIBERONC, Madrid, Spain
| | | | - Audun Kvalvaag
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Espen Stang
- Department of Pathology, Oslo University Hospital, Oslo, Norway
| | - Andreas Brech
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Alicia Llorente
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway.
- Department for Mechanical, Electronics and Chemical Engineering, Oslo Metropolitan University, Oslo, Norway.
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3
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Dell'Amico C, Angulo Salavarria MM, Takeo Y, Saotome I, Dell'Anno MT, Galimberti M, Pellegrino E, Cattaneo E, Louvi A, Onorati M. Microcephaly-associated protein WDR62 shuttles from the Golgi apparatus to the spindle poles in human neural progenitors. eLife 2023; 12:e81716. [PMID: 37272619 PMCID: PMC10241521 DOI: 10.7554/elife.81716] [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: 07/08/2022] [Accepted: 04/17/2023] [Indexed: 06/06/2023] Open
Abstract
WDR62 is a spindle pole-associated scaffold protein with pleiotropic functions. Recessive mutations in WDR62 cause structural brain abnormalities and account for the second most common cause of autosomal recessive primary microcephaly (MCPH), indicating WDR62 as a critical hub for human brain development. Here, we investigated WDR62 function in corticogenesis through the analysis of a C-terminal truncating mutation (D955AfsX112). Using induced Pluripotent Stem Cells (iPSCs) obtained from a patient and his unaffected parent, as well as isogenic corrected lines, we generated 2D and 3D models of human neurodevelopment, including neuroepithelial stem cells, cerebro-cortical progenitors, terminally differentiated neurons, and cerebral organoids. We report that WDR62 localizes to the Golgi apparatus during interphase in cultured cells and human fetal brain tissue, and translocates to the mitotic spindle poles in a microtubule-dependent manner. Moreover, we demonstrate that WDR62 dysfunction impairs mitotic progression and results in alterations of the neurogenic trajectories of iPSC neuroderivatives. In summary, impairment of WDR62 localization and function results in severe neurodevelopmental abnormalities, thus delineating new mechanisms in the etiology of MCPH.
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Affiliation(s)
- Claudia Dell'Amico
- Department of Biology, Unit of Cell and Developmental Biology, University of PisaPisaItaly
| | | | - Yutaka Takeo
- Departments of Neurosurgery and Neuroscience, Yale School of MedicineNew HavenUnited States
| | - Ichiko Saotome
- Departments of Neurosurgery and Neuroscience, Yale School of MedicineNew HavenUnited States
| | | | - Maura Galimberti
- Dipartimento di Bioscienze, Università degli Studi di MilanoMilanItaly
- INGM, Istituto Nazionale Genetica MolecolareMilanItaly
| | - Enrica Pellegrino
- Department of Biology, Unit of Cell and Developmental Biology, University of PisaPisaItaly
- Host-Pathogen Interactions in Tuberculosis Laboratory, The Francis Crick InstituteLondonUnited Kingdom
| | - Elena Cattaneo
- Dipartimento di Bioscienze, Università degli Studi di MilanoMilanItaly
- INGM, Istituto Nazionale Genetica MolecolareMilanItaly
| | - Angeliki Louvi
- Departments of Neurosurgery and Neuroscience, Yale School of MedicineNew HavenUnited States
| | - Marco Onorati
- Department of Biology, Unit of Cell and Developmental Biology, University of PisaPisaItaly
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4
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Mironov AA, Beznoussenko GV. The Regulated Secretion and Models of Intracellular Transport: The Goblet Cell as an Example. Int J Mol Sci 2023; 24:ijms24119560. [PMID: 37298509 DOI: 10.3390/ijms24119560] [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: 03/28/2023] [Revised: 05/24/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023] Open
Abstract
Transport models are extremely important to map thousands of proteins and their interactions inside a cell. The transport pathways of luminal and at least initially soluble secretory proteins synthesized in the endoplasmic reticulum can be divided into two groups: the so-called constitutive secretory pathway and regulated secretion (RS) pathway, in which the RS proteins pass through the Golgi complex and are accumulated into storage/secretion granules (SGs). Their contents are released when stimuli trigger the fusion of SGs with the plasma membrane (PM). In specialized exocrine, endocrine, and nerve cells, the RS proteins pass through the baso-lateral plasmalemma. In polarized cells, the RS proteins secrete through the apical PM. This exocytosis of the RS proteins increases in response to external stimuli. Here, we analyze RS in goblet cells to try to understand the transport model that can be used for the explanation of the literature data related to the intracellular transport of their mucins.
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Affiliation(s)
- Alexander A Mironov
- Department of Cell Biology, IFOM ETS-The AIRC Institute of Molecular Oncology, Via Adamello, 16, 20139 Milan, Italy
| | - Galina V Beznoussenko
- Department of Cell Biology, IFOM ETS-The AIRC Institute of Molecular Oncology, Via Adamello, 16, 20139 Milan, Italy
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5
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De Vincentiis S, Baggiani M, Merighi F, Cappello V, Lopane J, Di Caprio M, Costa M, Mainardi M, Onorati M, Raffa V. Low Forces Push the Maturation of Neural Precursors into Neurons. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2205871. [PMID: 37058009 DOI: 10.1002/smll.202205871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 03/15/2023] [Indexed: 06/19/2023]
Abstract
Mechanical stimulation modulates neural development and neuronal activity. In a previous study, magnetic "nano-pulling" is proposed as a tool to generate active forces. By loading neural cells with magnetic nanoparticles (MNPs), a precise force vector is remotely generated through static magnetic fields. In the present study, human neural stem cells (NSCs) are subjected to a standard differentiation protocol, in the presence or absence of nano-pulling. Under mechanical stimulation, an increase in the length of the neural processes which showed an enrichment in microtubules, endoplasmic reticulum, and mitochondria is found. A stimulation lasting up to 82 days induces a strong remodeling at the level of synapse density and a re-organization of the neuronal network, halving the time required for the maturation of neural precursors into neurons. The MNP-loaded NSCs are then transplanted into mouse spinal cord organotypic slices, demonstrating that nano-pulling stimulates the elongation of the NSC processes and modulates their orientation even in an ex vivo model. Thus, it is shown that active mechanical stimuli can guide the outgrowth of NSCs transplanted into the spinal cord tissue. The findings suggest that mechanical forces play an important role in neuronal maturation which could be applied in regenerative medicine.
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Affiliation(s)
| | - Matteo Baggiani
- Department of Biology, Università di Pisa, Pisa, 56127, Italy
| | | | - Valentina Cappello
- Center for Materials Interfaces, Istituto Italiano di Tecnologia, Pontedera, 56025, Italy
| | - Jakub Lopane
- Department of Biology, Università di Pisa, Pisa, 56127, Italy
| | - Mariachiara Di Caprio
- Laboratory of Biology "Bio@SNS", Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa, 56126, Italy
| | - Mario Costa
- Neuroscience Institute, National Research Council, via Giuseppe Moruzzi 1, Pisa, 56124, Italy
| | - Marco Mainardi
- Neuroscience Institute, National Research Council, via Giuseppe Moruzzi 1, Pisa, 56124, Italy
| | - Marco Onorati
- Department of Biology, Università di Pisa, Pisa, 56127, Italy
| | - Vittoria Raffa
- Department of Biology, Università di Pisa, Pisa, 56127, Italy
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6
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Smeele PH, Vaccari T. Snapshots from within the cell: Novel trafficking and non trafficking functions of Snap29 during tissue morphogenesis. Semin Cell Dev Biol 2023; 133:42-52. [PMID: 35256275 DOI: 10.1016/j.semcdb.2022.02.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/17/2022] [Accepted: 02/24/2022] [Indexed: 01/27/2023]
Abstract
Membrane trafficking is a core cellular process that supports diversification of cell shapes and behaviors relevant to morphogenesis during development and in adult organisms. However, how precisely trafficking components regulate specific differentiation programs is incompletely understood. Snap29 is a multifaceted Soluble N-ethylmaleimide-sensitive factor Attachment protein Receptor, involved in a wide range of trafficking and non-trafficking processes in most cells. A body of knowledge, accrued over more than two decades since its discovery, reveals that Snap29 is essential for establishing and maintaining the operation of a number of cellular events that support cell polarity and signaling. In this review, we first summarize established functions of Snap29 and then we focus on novel ones in the context of autophagy, Golgi trafficking and vesicle fusion at the plasma membrane, as well as on non-trafficking activities of Snap29. We further describe emerging evidence regarding the compartmentalisation and regulation of Snap29. Finally, we explore how the loss of distinct functions of human Snap29 may lead to the clinical manifestations of congenital disorders such as CEDNIK syndrome and how altered SNAP29 activity may contribute to the pathogenesis of cancer, viral infection and neurodegenerative diseases.
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Affiliation(s)
- Paulien H Smeele
- Department of Biosciences, Università Degli Studi Di Milano, Milan, Italy
| | - Thomas Vaccari
- Department of Biosciences, Università Degli Studi Di Milano, Milan, Italy.
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7
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Lin X, Li Z, Bu D, Liu W, Li Z, Wei R, Yu M. Multiple organelle-targeted near-infrared fluorescent probes toward pH and viscosity. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 283:121665. [PMID: 35961205 DOI: 10.1016/j.saa.2022.121665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/11/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
Organelles, including mitochondria (mito), lysosomes (lyso), endoplasmic reticulum (ER), Golgi apparatus (Golgi), and ribosome et al., play a vital role in maintaining the regular work of the cell. Viscosity is an essential parameter in the cellular microenvironment. Herein, four viscosity-sensitive near-infrared fluorescent probes DMPC, DEPC, DHDM and DHDV that can simultaneously target multiple organelles were synthesized. As the viscosity increased, the fluorescence intensity of the probes gradually increased due to the hindrance of the rotation of the carbon-carbon single bond. The fluorescence intensity of DHDV increased by about 453 times, and the fluorescence quantum yield also increased from 0.051 to 0.681. Cell experiments indicated the probes could simultaneously target four kinds of organelles, and the four probes could also track mitochondria with no dependence on membrane potential. Further experiments showed that the probes could detect viscosity changes in lyso and mito. In addition, the probes also demonstrated the advantages of low cytotoxicity, good anti-interference and stability, providing a simple and effective tool for studying the activity of organelles with changing viscosity signals.
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Affiliation(s)
- Xuemei Lin
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Zhe Li
- Department of Cerebrovascular Diseases, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Dandan Bu
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Wenjing Liu
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China
| | - Zhanxian Li
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
| | - Ruixue Wei
- Department of Cerebrovascular Diseases, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
| | - Mingming Yu
- Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
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8
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Syntaxin 18 regulates the DNA damage response and epithelial-to-mesenchymal transition to promote radiation resistance of lung cancer. Cell Death Dis 2022; 13:529. [PMID: 35668077 PMCID: PMC9170725 DOI: 10.1038/s41419-022-04978-4] [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: 10/05/2021] [Revised: 05/18/2022] [Accepted: 05/26/2022] [Indexed: 01/21/2023]
Abstract
Radiotherapy is an important modality in lung cancer treatment. Despite advances in treatment planning and dose delivery, patient benefit is still limited by in-field relapse and metastatic recurrence. Simultaneous application of cisplatinum-based chemotherapy leads to moderately improved outcomes, thus providing proof-of-concept for radiosensitization strategies in lung cancer. In an unbiased functional genetic screen for radiosensitization targets in lung cancer, we identified syntaxin 18, a protein involved in retrograde vesicular transport between the Golgi apparatus and endoplasmic reticulum, as mediator of radioresistance. Downregulation of endogenous syntaxin 18 specifically reduced clonogenic survival of radioresistant and radiosensitive lung cancer cells following X-radiation. Gene expression programs regulating DNA repair, mitotic checkpoints and mitosis were altered in isogenic cells with reduced syntaxin 18 expression. Functionally, this translated into impaired DNA damage-induced cell cycle checkpoints leading to cell death by mitotic catastrophe. Interestingly, downregulation of syntaxin 18 in lung cancer cells also impaired expression of markers of epithelial-mesenchymal-transition, and reduced migration and invasion capacity. These findings suggest that syntaxin 18 is a key player regulating genes responsible for controlling the growth of the primary tumor as well as metastases upon radiotherapy of lung cancer. They provide a promising lead for biologically rational radiosensitization strategies impacting on radiation-induced cell death as well as metastasis.
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9
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Comparison of the Cisterna Maturation-Progression Model with the Kiss-and-Run Model of Intra-Golgi Transport: Role of Cisternal Pores and Cargo Domains. Int J Mol Sci 2022; 23:ijms23073590. [PMID: 35408951 PMCID: PMC8999060 DOI: 10.3390/ijms23073590] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/11/2022] [Accepted: 03/16/2022] [Indexed: 12/22/2022] Open
Abstract
The Golgi complex is the central station of the secretory pathway. Knowledge about the mechanisms of intra-Golgi transport is inconsistent. Here, we compared the explanatory power of the cisterna maturation-progression model and the kiss-and-run model. During intra-Golgi transport, conventional cargoes undergo concentration and form cisternal distensions or distinct membrane domains that contain only one membrane cargo. These domains and distension are separated from the rest of the Golgi cisternae by rows of pores. After the arrival of any membrane cargo or a large cargo aggregate at the Golgi complex, the cis-Golgi SNAREs become enriched within the membrane of cargo-containing domains and then replaced by the trans-Golgi SNAREs. During the passage of these domains, the number of cisternal pores decreases. Restoration of the cisternal pores is COPI-dependent. Our observations are more in line with the kiss-and-run model.
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10
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Cali E, Rocca C, Salpietro V, Houlden H. Epileptic Phenotypes Associated With SNAREs and Related Synaptic Vesicle Exocytosis Machinery. Front Neurol 2022; 12:806506. [PMID: 35095745 PMCID: PMC8792400 DOI: 10.3389/fneur.2021.806506] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 11/16/2021] [Indexed: 01/29/2023] Open
Abstract
SNAREs (soluble N-ethylmaleimide sensitive factor attachment protein receptor) are an heterogeneous family of proteins that, together with their key regulators, are implicated in synaptic vesicle exocytosis and synaptic transmission. SNAREs represent the core component of this protein complex. Although the specific mechanisms of the SNARE machinery is still not completely uncovered, studies in recent years have provided a clearer understanding of the interactions regulating the essential fusion machinery for neurotransmitter release. Mutations in genes encoding SNARE proteins or SNARE complex associated proteins have been associated with a variable spectrum of neurological conditions that have been recently defined as “SNAREopathies.” These include neurodevelopmental disorder, autism spectrum disorder (ASD), movement disorders, seizures and epileptiform abnormalities. The SNARE phenotypic spectrum associated with seizures ranges from simple febrile seizures and infantile spasms, to severe early-onset epileptic encephalopathies. Our study aims to review and delineate the epileptic phenotypes associated with dysregulation of synaptic vesicle exocytosis and transmission, focusing on the main proteins of the SNARE core complex (STX1B, VAMP2, SNAP25), tethering complex (STXBP1), and related downstream regulators.
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Affiliation(s)
- Elisa Cali
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Clarissa Rocca
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Vincenzo Salpietro
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Henry Houlden
- MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
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11
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Tang Q, Gao P, Arzberger T, Höllerhage M, Herms J, Höglinger G, Koeglsperger T. Alpha-Synuclein defects autophagy by impairing SNAP29-mediated autophagosome-lysosome fusion. Cell Death Dis 2021; 12:854. [PMID: 34535638 PMCID: PMC8448865 DOI: 10.1038/s41419-021-04138-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 08/07/2021] [Accepted: 08/26/2021] [Indexed: 02/08/2023]
Abstract
Dopaminergic (DA) cell death in Parkinson's disease (PD) is associated with the gradual appearance of neuronal protein aggregates termed Lewy bodies (LBs) that are comprised of vesicular membrane structures and dysmorphic organelles in conjunction with the protein alpha-Synuclein (α-Syn). Although the exact mechanism of neuronal aggregate formation and death remains elusive, recent research suggests α-Syn-mediated alterations in the lysosomal degradation of aggregated proteins and organelles - a process termed autophagy. Here, we used a combination of molecular biology and immunochemistry to investigate the effect of α-Syn on autophagy turnover in cultured human DA neurons and in human post-mortem brain tissue. We found α-Syn overexpression to reduce autophagy turnover by compromising the fusion of autophagosomes with lysosomes, thus leading to a decrease in the formation of autolysosomes. In accord with a compensatory increase in the plasma membrane fusion of autophagosomes, α-Syn enhanced the number of extracellular vesicles (EV) and the abundance of autophagy-associated proteins in these EVs. Mechanistically, α-Syn decreased the abundance of the v-SNARE protein SNAP29, a member of the SNARE complex mediating autophagolysosome fusion. In line, SNAP29 knockdown mimicked the effect of α-Syn on autophagy whereas SNAP29 co-expression reversed the α-Syn-induced changes on autophagy turnover and EV release and ameliorated DA neuronal cell death. In accord with our results from cultured neurons, we found a stage-dependent reduction of SNAP29 in SNc DA neurons from human post-mortem brain tissue of Lewy body pathology (LBP) cases. In summary, our results thus demonstrate a previously unknown effect of α-Syn on intracellular autophagy-associated SNARE proteins and, as a consequence, a reduced autolysosome fusion. As such, our findings will therefore support the investigation of autophagy-associated pathological changes in PD.
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Affiliation(s)
- Qilin Tang
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.5252.00000 0004 1936 973XDepartment of Neurology, Ludwig Maximilian University, Munich, Germany
| | - Pan Gao
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.6936.a0000000123222966Technical University of Munich, Munich, Germany
| | - Thomas Arzberger
- grid.5252.00000 0004 1936 973XCentre of Neuropathology and Prion Research, Ludwig, Maximilian University, Munich, Germany ,grid.5252.00000 0004 1936 973XDepartment of Psychiatry and Psychotherapy, Ludwig Maximilian University, Munich, Germany
| | - Matthias Höllerhage
- grid.10423.340000 0000 9529 9877Department of Neurology, Hannover Medical School (MHH), Hannover, Germany
| | - Jochen Herms
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.5252.00000 0004 1936 973XCentre of Neuropathology and Prion Research, Ludwig, Maximilian University, Munich, Germany ,grid.452617.3Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Günter Höglinger
- grid.10423.340000 0000 9529 9877Department of Neurology, Hannover Medical School (MHH), Hannover, Germany ,grid.424247.30000 0004 0438 0426Department of Translational Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Thomas Koeglsperger
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.5252.00000 0004 1936 973XDepartment of Neurology, Ludwig Maximilian University, Munich, Germany
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