1
|
Schmied C, Ebner M, Samsó P, Van Der Veen R, Haucke V, Lehmann M. OrgaMapper: a robust and easy-to-use workflow for analyzing organelle positioning. BMC Biol 2024; 22:220. [PMID: 39343900 PMCID: PMC11440938 DOI: 10.1186/s12915-024-02015-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 09/18/2024] [Indexed: 10/01/2024] Open
Abstract
BACKGROUND Eukaryotic cells are highly compartmentalized by a variety of organelles that carry out specific cellular processes. The position of these organelles within the cell is elaborately regulated and vital for their function. For instance, the position of lysosomes relative to the nucleus controls their degradative capacity and is altered in pathophysiological conditions. The molecular components orchestrating the precise localization of organelles remain incompletely understood. A confounding factor in these studies is the fact that organelle positioning is surprisingly non-trivial to address e.g., perturbations that affect the localization of organelles often lead to secondary phenotypes such as changes in cell or organelle size. These phenotypes could potentially mask effects or lead to the identification of false positive hits. To uncover and test potential molecular components at scale, accurate and easy-to-use analysis tools are required that allow robust measurements of organelle positioning. RESULTS Here, we present an analysis workflow for the faithful, robust, and quantitative analysis of organelle positioning phenotypes. Our workflow consists of an easy-to-use Fiji plugin and an R Shiny App. These tools enable users without background in image or data analysis to (1) segment single cells and nuclei and to detect organelles, (2) to measure cell size and the distance between detected organelles and the nucleus, (3) to measure intensities in the organelle channel plus one additional channel, (4) to measure radial intensity profiles of organellar markers, and (5) to plot the results in informative graphs. Using simulated data and immunofluorescent images of cells in which the function of known factors for lysosome positioning has been perturbed, we show that the workflow is robust against common problems for the accurate assessment of organelle positioning such as changes of cell shape and size, organelle size and background. CONCLUSIONS OrgaMapper is a versatile, robust, and easy-to-use automated image analysis workflow that can be utilized in microscopy-based hypothesis testing and screens. It effectively allows for the mapping of the intracellular space and enables the discovery of novel regulators of organelle positioning.
Collapse
Affiliation(s)
- Christopher Schmied
- Leibniz-Forschungsinstitut Für Molekulare Pharmakologie (FMP), Robert-Roessle-Straße 10, Berlin, 13125, Germany.
- Present address: EU-OPENSCREEN ERIC, Robert-Roessle-Straße 10, Berlin, 13125, Germany.
| | - Michael Ebner
- Leibniz-Forschungsinstitut Für Molekulare Pharmakologie (FMP), Robert-Roessle-Straße 10, Berlin, 13125, Germany
| | - Paula Samsó
- Leibniz-Forschungsinstitut Für Molekulare Pharmakologie (FMP), Robert-Roessle-Straße 10, Berlin, 13125, Germany
| | - Rozemarijn Van Der Veen
- Leibniz-Forschungsinstitut Für Molekulare Pharmakologie (FMP), Robert-Roessle-Straße 10, Berlin, 13125, Germany
| | - Volker Haucke
- Leibniz-Forschungsinstitut Für Molekulare Pharmakologie (FMP), Robert-Roessle-Straße 10, Berlin, 13125, Germany
- Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, Berlin, 14195, Germany
| | - Martin Lehmann
- Leibniz-Forschungsinstitut Für Molekulare Pharmakologie (FMP), Robert-Roessle-Straße 10, Berlin, 13125, Germany
| |
Collapse
|
2
|
Hana TA, Mousa VG, Lin A, Haj-Hussein RN, Michael AH, Aziz MN, Kamaridinova SU, Basnet S, Ormerod KG. Developmental and physiological impacts of pathogenic human huntingtin protein in the nervous system. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.30.610525. [PMID: 39257834 PMCID: PMC11383668 DOI: 10.1101/2024.08.30.610525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2024]
Abstract
Huntington's Disease (HD) is a neurodegenerative disorder, part of the nine identified inherited polyglutamine (polyQ) diseases. Most commonly, HD pathophysiology manifests in middle-aged adults with symptoms including progressive loss of motor control, cognitive decline, and psychiatric disturbances. Associated with the pathophysiology of HD is the formation of insoluble fragments of the huntingtin protein (htt) that tend to aggregate in the nucleus and cytoplasm of neurons. To track both the intracellular progression of the aggregation phenotype as well as the physiological deficits associated with mutant htt, two constructs of human HTT were expressed with varying polyQ lengths, non-pathogenic-htt (Q15, NP-htt) and pathogenic-htt (Q138, P-htt), with an N-terminal RFP tag for in vivo visualization. P-htt aggregates accumulate in the ventral nerve cord cell bodies as early as 24 hours post hatching and significant aggregates form in the segmental nerve branches at 48 hours post hatching. Organelle trafficking up-and downstream of aggregates formed in motor neurons showed severe deficits in trafficking dynamics. To explore putative downstream deficits of htt aggregation, ultrastructural changes of presynaptic motor neurons and muscles were assessed, but no significant effects were observed. However, the force and kinetics of muscle contractions were severely affected in P-htt animals, reminiscent of human chorea. Reduced muscle force production translated to altered locomotory behavior. A novel HD aggregation model was established to track htt aggregation throughout adulthood in the wing, showing similar aggregation patterns with larvae. Expressing P-htt in the adult nervous system resulted in significantly reduced lifespan, which could be partially rescued by feeding flies the mTOR inhibitor rapamycin. These findings advance our understanding of htt aggregate progression as well the downstream physiological impacts on the nervous system and peripheral tissues.
Collapse
|
3
|
Mishra H, Schlack-Leigers C, Lim EL, Thieck O, Magg T, Raedler J, Wolf C, Klein C, Ewers H, Lee-Kirsch MA, Meierhofer D, Hauck F, Majer O. Disrupted degradative sorting of TLR7 is associated with human lupus. Sci Immunol 2024; 9:eadi9575. [PMID: 38207015 DOI: 10.1126/sciimmunol.adi9575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 12/22/2023] [Indexed: 01/13/2024]
Abstract
Hyperactive TLR7 signaling has long been appreciated as driver of autoimmune disease in mouse models. Recently, gain-of-function mutations in TLR7 were identified as a monogenic cause of human lupus. TLR7 is an intracellular transmembrane receptor, sensing RNA breakdown products within late endosomes. Here, we show that endosome dysfunction leads to unrestricted TLR7 signaling and is associated with human lupus. The late endosomal BORC complex together with the small GTPase Arl8b controls intracellular TLR7 levels by regulating receptor turnover. This requires a direct interaction between the TLR7-associated trafficking factor Unc93b1 and Arl8b. We identified an UNC93B1 mutation in a patient with childhood-onset lupus, which results in reduced BORC interaction and endosomal TLR7 accumulation. Therefore, a failure to control TLR7 turnover is sufficient to break immunological tolerance to nucleic acids. Our results highlight the importance of an intact endomembrane system in preventing pathological TLR7 signaling and autoimmune disease.
Collapse
Affiliation(s)
- Harshita Mishra
- Max Planck Institute for Infection Biology, Berlin 10117, Germany
| | - Claire Schlack-Leigers
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin 14195, Germany
| | - Ee Lyn Lim
- Max Planck Institute for Infection Biology, Berlin 10117, Germany
| | - Oliver Thieck
- Max Planck Institute for Infection Biology, Berlin 10117, Germany
| | - Thomas Magg
- Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, Ludwig-Maximilians-Universität München, Munich 80337, Germany
| | - Johannes Raedler
- Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, Ludwig-Maximilians-Universität München, Munich 80337, Germany
| | - Christine Wolf
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden 01307, Germany
| | - Christoph Klein
- Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, Ludwig-Maximilians-Universität München, Munich 80337, Germany
| | - Helge Ewers
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin 14195, Germany
| | - Min Ae Lee-Kirsch
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden 01307, Germany
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, Berlin 14195, Germany
| | - Fabian Hauck
- Department of Pediatrics, Dr. von Hauner Children's Hospital, University Hospital, Ludwig-Maximilians-Universität München, Munich 80337, Germany
| | - Olivia Majer
- Max Planck Institute for Infection Biology, Berlin 10117, Germany
| |
Collapse
|
4
|
Chen JH, Xu N, Qi L, Yan HH, Wan FY, Gao F, Fu C, Cang C, Lu B, Bi GQ, Tang AH. Reduced lysosomal density in neuronal dendrites mediates deficits in synaptic plasticity in Huntington's disease. Cell Rep 2023; 42:113573. [PMID: 38096054 DOI: 10.1016/j.celrep.2023.113573] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 10/15/2023] [Accepted: 11/27/2023] [Indexed: 12/30/2023] Open
Abstract
Huntington's disease (HD) usually causes cognitive disorders, including learning difficulties, that emerge before motor symptoms. Mutations related to lysosomal trafficking are linked to the pathogenesis of neurological diseases, whereas the cellular mechanisms remain elusive. Here, we discover a reduction in the dendritic density of lysosomes in the hippocampus that correlates with deficits in synaptic plasticity and spatial learning in early CAG-140 HD model mice. We directly manipulate intraneuronal lysosomal positioning with light-induced CRY2:CIB1 dimerization and demonstrate that lysosomal abundance in dendrites positively modulates long-term potentiation of glutamatergic synapses onto the neuron. This modulation depends on lysosomal Ca2+ release, which further promotes endoplasmic reticulum (ER) entry into spines. Importantly, optogenetically restoring lysosomal density in dendrites rescues the synaptic plasticity deficit in hippocampal slices of CAG-140 mice. Our data reveal dendritic lysosomal density as a modulator of synaptic plasticity and suggest a role of lysosomal mispositioning in cognitive decline in HD.
Collapse
Affiliation(s)
- Jia-Hui Chen
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China; Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230088, China; CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China.
| | - Na Xu
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China; CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China
| | - Lei Qi
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230088, China
| | - Hao-Hao Yan
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China; CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China
| | - Fang-Yan Wan
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China; CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China
| | - Feng Gao
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
| | - Chuanhai Fu
- CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China
| | - Chunlei Cang
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China; CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China
| | - Boxun Lu
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Huashan Hospital, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Guo-Qiang Bi
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230088, China; CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China; Interdisciplinary Center for Brain Information, The Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Guangdong 518055, China
| | - Ai-Hui Tang
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China; Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei 230088, China; CAS Key Laboratory of Brain Function and Disease, MOE Key Laboratory for Membrane-less Organelles & Cellular Dynamics, Neurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei 230027, China.
| |
Collapse
|
5
|
Vitet H, Bruyère J, Xu H, Séris C, Brocard J, Abada YS, Delatour B, Scaramuzzino C, Venance L, Saudou F. Huntingtin recruits KIF1A to transport synaptic vesicle precursors along the mouse axon to support synaptic transmission and motor skill learning. eLife 2023; 12:e81011. [PMID: 37431882 PMCID: PMC10365837 DOI: 10.7554/elife.81011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 07/06/2023] [Indexed: 07/12/2023] Open
Abstract
Neurotransmitters are released at synapses by synaptic vesicles (SVs), which originate from SV precursors (SVPs) that have traveled along the axon. Because each synapse maintains a pool of SVs, only a small fraction of which are released, it has been thought that axonal transport of SVPs does not affect synaptic function. Here, studying the corticostriatal network both in microfluidic devices and in mice, we find that phosphorylation of the Huntingtin protein (HTT) increases axonal transport of SVPs and synaptic glutamate release by recruiting the kinesin motor KIF1A. In mice, constitutive HTT phosphorylation causes SV over-accumulation at synapses, increases the probability of SV release, and impairs motor skill learning on the rotating rod. Silencing KIF1A in these mice restored SV transport and motor skill learning to wild-type levels. Axonal SVP transport within the corticostriatal network thus influences synaptic plasticity and motor skill learning.
Collapse
Affiliation(s)
- Hélène Vitet
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut NeuroscienceGrenobleFrance
| | - Julie Bruyère
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut NeuroscienceGrenobleFrance
| | - Hao Xu
- Center for Interdisciplinary Research in Biology, College de France, CNRS, INSERM, Université PSLParisFrance
| | - Claire Séris
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut NeuroscienceGrenobleFrance
| | - Jacques Brocard
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut NeuroscienceGrenobleFrance
| | - Yah-Sé Abada
- Sorbonne Université, Institut du Cerveau, Paris Brain Institute, ICM, Inserm U1127, CNRS UMR7225ParisFrance
| | - Benoît Delatour
- Sorbonne Université, Institut du Cerveau, Paris Brain Institute, ICM, Inserm U1127, CNRS UMR7225ParisFrance
| | - Chiara Scaramuzzino
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut NeuroscienceGrenobleFrance
| | - Laurent Venance
- Center for Interdisciplinary Research in Biology, College de France, CNRS, INSERM, Université PSLParisFrance
| | - Frédéric Saudou
- Univ. Grenoble Alpes, Inserm, U1216, CHU Grenoble Alpes, Grenoble Institut NeuroscienceGrenobleFrance
| |
Collapse
|
6
|
Abstract
Neurons are markedly compartmentalized, which makes them reliant on axonal transport to maintain their health. Axonal transport is important for anterograde delivery of newly synthesized macromolecules and organelles from the cell body to the synapse and for the retrograde delivery of signaling endosomes and autophagosomes for degradation. Dysregulation of axonal transport occurs early in neurodegenerative diseases and plays a key role in axonal degeneration. Here, we provide an overview of mechanisms for regulation of axonal transport; discuss how these mechanisms are disrupted in neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, hereditary spastic paraplegia, amyotrophic lateral sclerosis, and Charcot-Marie-Tooth disease; and discuss therapeutic approaches targeting axonal transport.
Collapse
|
7
|
Prowse ENP, Chaudhary AR, Sharon D, Hendricks AG. Huntingtin S421 phosphorylation increases kinesin and dynein engagement on early endosomes and lysosomes. Biophys J 2023; 122:1168-1184. [PMID: 36772794 PMCID: PMC10111264 DOI: 10.1016/j.bpj.2023.02.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 12/20/2022] [Accepted: 02/07/2023] [Indexed: 02/11/2023] Open
Abstract
Huntingtin (HTT) is a scaffolding protein that recruits motor proteins to vesicular cargoes, enabling it to regulate kinesin-1, dynein, and myosin-VI-dependent transport. To maintain the native stoichiometry of HTT with its interacting partners, we used CRISPR/Cas9 to induce a phosphomimetic mutation of the endogenous HTT at S421 (HTT-S421D). Using single-particle tracking, optical tweezers, and immunofluorescence, we examined the effects of this mutation on the motility of early endosomes and lysosomes. In HTT-S421D cells, lysosomes exhibit longer displacements and higher processive fractions compared with wild-type (HTT-WT) cells. Kinesins and dyneins exert greater forces on early endosomes and lysosomes in cells expressing HTT-S421D. In addition, endosomes bind to microtubules faster and are more resistant to detachment under load. The recruitment of kinesins and dyneins to microtubules is enhanced in HTT-S421D cells. In contrast, overexpression of HTT had variable effects on the processivity, displacement, and directional bias of both early endosomes and lysosomes. These data indicate that phosphorylation of the endogenous HTT causes early endosomes and lysosomes to move longer distances and more processively by recruiting and activating both kinesin-1 and dynein.
Collapse
Affiliation(s)
- Emily N P Prowse
- Bioengineering Department, McGill University, Montreal, Quebec, Canada
| | | | - David Sharon
- Bioengineering Department, McGill University, Montreal, Quebec, Canada
| | - Adam G Hendricks
- Bioengineering Department, McGill University, Montreal, Quebec, Canada.
| |
Collapse
|
8
|
Ballesteros-Álvarez J, Nguyen W, Sivapatham R, Rane A, Andersen JK. Urolithin A reduces amyloid-beta load and improves cognitive deficits uncorrelated with plaque burden in a mouse model of Alzheimer's disease. GeroScience 2022; 45:1095-1113. [PMID: 36576642 PMCID: PMC9886708 DOI: 10.1007/s11357-022-00708-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 12/03/2022] [Indexed: 12/29/2022] Open
Abstract
In the present study, we investigated the effects of urolithin A (UA), a metabolite generated from ellagic acid via its metabolism by gut bacteria, as an autophagy activator with potential neuroprotective activity. WT and 3xTg-AD mice were administered long-term intermittent dietary supplementation with UA. UA was found to prevent deficits in spatial memory, cued fear response, and exploratory behavior in this model. It also decreased the Aβ plaque burden in areas of the hippocampus where these protein deposits are prominent in the model. Interestingly, correlation analyses demonstrate that Aβ plaque burden positively correlates with enhanced spatial memory in 3xTg-AD mice on a control diet but not in those supplemented with UA. In contrast, Aβ42 abundance in cortical and hippocampal homogenates negatively correlate with spatial memory in UA-fed mice. Our data suggest that plaque formation may be a protective mechanism against neurodegeneration and cognitive decline and that targeting the generation of proteotoxic Aβ species might be a more successful approach in halting disease progression. UA was also found to extend lifespan in normal aging mice. Mechanistically, we demonstrate that UA is able to induce autophagy and to increase Aβ clearance in neuronal cell lines. In summary, our studies reveal UA, likely via its actions as a autophagy inducer, is capable of removing Aβ from neurons and its dietary administration prevents the onset of cognitive deficits associated with pathological Aβ deposition in the 3xTg-AD mouse model as well as extending lifespan in normal aging mice.
Collapse
Affiliation(s)
| | - Wynnie Nguyen
- Buck Institute for Research on Aging, Novato, CA USA
| | | | - Anand Rane
- Buck Institute for Research on Aging, Novato, CA USA
| | | |
Collapse
|
9
|
Huntingtin and Other Neurodegeneration-Associated Proteins in the Development of Intracellular Pathologies: Potential Target Search for Therapeutic Intervention. Int J Mol Sci 2022; 23:ijms232415533. [PMID: 36555175 PMCID: PMC9779313 DOI: 10.3390/ijms232415533] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022] Open
Abstract
Neurodegenerative diseases are currently incurable. Numerous experimental data accumulated over the past fifty years have brought us closer to understanding the molecular and cell mechanisms responsible for their development. However, these data are not enough for a complete understanding of the genesis of these diseases, nor to suggest treatment methods. It turns out that many cellular pathologies developing during neurodegeneration coincide from disease to disease. These observations give hope to finding a common intracellular target(s) and to offering a universal method of treatment. In this review, we attempt to analyze data on similar cellular disorders among neurodegenerative diseases in general, and polyglutamine neurodegenerative diseases in particular, focusing on the interaction of various proteins involved in the development of neurodegenerative diseases with various cellular organelles. The main purposes of this review are: (1) to outline the spectrum of common intracellular pathologies and to answer the question of whether it is possible to find potential universal target(s) for therapeutic intervention; (2) to identify specific intracellular pathologies and to speculate about a possible general approach for their treatment.
Collapse
|
10
|
Chadet S, Allard J, Brisson L, Lopez-Charcas O, Lemoine R, Heraud A, Lerondel S, Guibon R, Fromont G, Le Pape A, Angoulvant D, Jiang LH, Murrell-Lagnado R, Roger S. P2x4 receptor promotes mammary cancer progression by sustaining autophagy and associated mesenchymal transition. Oncogene 2022; 41:2920-2931. [DOI: 10.1038/s41388-022-02297-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 03/18/2022] [Accepted: 03/24/2022] [Indexed: 12/22/2022]
|
11
|
Williamson CD, Guardia CM, De Pace R, Bonifacino JS, Saric A. Measurement of Lysosome Positioning by Shell Analysis and Line Scan. Methods Mol Biol 2022; 2473:285-306. [PMID: 35819772 PMCID: PMC11072972 DOI: 10.1007/978-1-0716-2209-4_19] [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] [Indexed: 06/15/2023]
Abstract
Lysosomes are membrane-bound organelles that degrade diverse biomolecules and regulate a multitude of other essential processes including cell growth and metabolism, signaling, plasma membrane repair and infection. Such diverse functions of lysosomes are highly coordinated in space and time and are therefore tightly coupled to the directional transport of the organelles within the cytoplasm. Thus, robust quantitative assessments of lysosome positioning within the cell provide a valuable tool for researchers interested in understanding these multifunctional organelles. Here, we present point-by-point methodology to measure lysosome positioning by two straight forward and widely used techniques: shell analysis and line scan.
Collapse
Affiliation(s)
- Chad D Williamson
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Carlos M Guardia
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Raffaella De Pace
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Amra Saric
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, ON, Canada.
| |
Collapse
|
12
|
Ballesteros‐Álvarez J, Andersen JK. mTORC2: The other mTOR in autophagy regulation. Aging Cell 2021; 20:e13431. [PMID: 34250734 PMCID: PMC8373318 DOI: 10.1111/acel.13431] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/15/2021] [Accepted: 06/24/2021] [Indexed: 12/13/2022] Open
Abstract
The mechanistic target of rapamycin (mTOR) has gathered significant attention as a ubiquitously expressed multimeric kinase with key implications for cell growth, proliferation, and survival. This kinase forms the central core of two distinct complexes, mTORC1 and mTORC2, which share the ability of integrating environmental, nutritional, and hormonal cues but which regulate separate molecular pathways that result in different cellular responses. Particularly, mTORC1 has been described as a major negative regulator of endosomal biogenesis and autophagy, a catabolic process that degrades intracellular components and organelles within the lysosomes and is thought to play a key role in human health and disease. In contrast, the role of mTORC2 in the regulation of autophagy has been considerably less studied despite mounting evidence this complex may regulate autophagy in a different and perhaps complementary manner to that of mTORC1. Genetic ablation of unique subunits is currently being utilized to study the differential effects of the two mTOR complexes. RICTOR is the best‐described subunit specific to mTORC2 and as such has become a useful tool for investigating the specific actions of this complex. The development of complex‐specific inhibitors for mTORC2 is also an area of intense interest. Studies to date have demonstrated that mTORC1/2 complexes each signal to a variety of exclusive downstream molecules with distinct biological roles. Pinpointing the particular effects of these downstream effectors is crucial toward the development of novel therapies aimed at accurately modulating autophagy in the context of human aging and disease.
Collapse
|
13
|
Ghosh A, Singh S. Regulation Of Microtubule: Current Concepts And Relevance To Neurodegenerative Diseases. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2021; 21:656-679. [PMID: 34323203 DOI: 10.2174/1871527320666210728144043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 01/05/2021] [Accepted: 02/23/2021] [Indexed: 11/22/2022]
Abstract
Neurodevelopmental disorders (NDDs) are abnormalities linked to neuronal structure and irregularities associated with the proliferation of cells, transportation, and differentiation. NDD also involves synaptic circuitry and neural network alterations known as synaptopathies. Microtubules (MTs) and MTs-associated proteins help to maintain neuronal health as well as their development. The microtubular dynamic structure plays a crucial role in the division of cells and forms mitotic spindles, thus take part in initiating stages of differentiation and polarization for various types of cells. The MTs also take part in the cellular death but MT-based cellular degenerations are not yet well excavated. In the last few years, studies have provided the protagonist activity of MTs in neuronal degeneration. In this review, we largely engrossed our discussion on the change of MT cytoskeleton structure, describing their organization, dynamics, transportation, and their failure causing NDDs. At end of this review, we are targeting the therapeutic neuroprotective strategies on clinical priority and also try to discuss the clues for the development of new MT-based therapy as a new pharmacological intervention. This will be a new potential site to block not only neurodegeneration but also promotes the regeneration of neurons.
Collapse
Affiliation(s)
- Anirban Ghosh
- Neuroscience Division, Department of Pharmacology, ISF College of Pharmacy, Moga-142001 Punjab, India
| | - Shamsher Singh
- Neuroscience Division, Department of Pharmacology, ISF College of Pharmacy, Moga-142001 Punjab, India
| |
Collapse
|
14
|
Inhibition of GSK-3 ameliorates the pathogenesis of Huntington's disease. Neurobiol Dis 2021; 154:105336. [PMID: 33753290 DOI: 10.1016/j.nbd.2021.105336] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/10/2021] [Accepted: 03/17/2021] [Indexed: 12/22/2022] Open
Abstract
In Huntington's disease (HD), the mutant huntingtin (mHtt) accumulates as toxic aggregates in the striatum tissue, with deleterious effects on motor-coordination and cognitive functions. Reducing the levels of mHtt is therefore a promising therapeutic strategy. We have previously reported that GSK-3 is a negative regulator of the autophagy/lysosome pathway, which is responsible for intracellular degradation, and is critically important for maintaining neuronal vitality. Thus, we hypothesized that inhibition of GSK-3 may trigger mHtt clearance thereby reducing mHtt cytotoxicity and improving HD symptoms. Here, we demonstrate that depletion or suppression of autophagy results in a massive accumulation of mHtt aggregates. Accordingly, mHtt aggregates were localized in lysosomes, but, mostly mislocalized from lysosomes in the absence of functional autophagy. Overexpression of GSK-3, particularly the α isozyme, increased the number of mHtt aggregates, while silencing GSK-3α/β, or treatment with a selective GSK-3 inhibitor, L807mts, previously described by us, reduced the amounts of mHtt aggregates. This effect was mediated by increased autophagic and lysosomal activity. Treating R6/2 mouse model of HD with L807mts, reduced striatal mHtt aggregates and elevated autophagic and lysosomal markers. The L807mts treatment also reduced hyperglycemia and improved motor-coordination functions in these mice. In addition, L807mts restored the expression levels of Sirt1, a critical neuroprotective factor in the HD striatum, along with its targets BDNF, DRPP-32, and active Akt, all provide neurotrophic/pro-survival support and typically decline in the HD brain. Our results provide strong evidence for a role for GSK-3 in the regulation of mHtt dynamics, and demonstrate the benefits of GSK-3 inhibition in reducing mHtt toxicity, providing neuroprotective support, and improving HD symptoms.
Collapse
|
15
|
Franco-Iborra S, Plaza-Zabala A, Montpeyo M, Sebastian D, Vila M, Martinez-Vicente M. Mutant HTT (huntingtin) impairs mitophagy in a cellular model of Huntington disease. Autophagy 2021; 17:672-689. [PMID: 32093570 PMCID: PMC8032238 DOI: 10.1080/15548627.2020.1728096] [Citation(s) in RCA: 87] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 01/27/2020] [Accepted: 02/04/2020] [Indexed: 12/13/2022] Open
Abstract
The precise degradation of dysfunctional mitochondria by mitophagy is essential for maintaining neuronal homeostasis. HTT (huntingtin) can interact with numerous other proteins and thereby perform multiple biological functions within the cell. In this study, we investigated the role of HTT during mitophagy and analyzed the impact of the expansion of its polyglutamine (polyQ) tract. HTT is involved in different mitophagy steps, promoting the physical proximity of different protein complexes during the initiation of mitophagy and recruiting mitophagy receptors essential for promoting the interaction between damaged mitochondria and the nascent autophagosome. The presence of the polyQ tract in mutant HTT affects the formation of these protein complexes and determines the negative consequences of mutant HTT on mitophagy, leading to the accumulation of damaged mitochondria and an increase in oxidative stress. These outcomes contribute to general mitochondrial dysfunction and neurodegeneration in Huntington disease.Abbreviations: AMPK: AMP-activated protein kinase; ATG13: autophagy related 13; BECN1: beclin 1, autophagy related; BNIP3: BCL2/adenovirus E1B interacting protein 3; BNIP3L/Nix: BCL2/adenovirus E1B interacting protein 3-like; CCCP: carbonyl cyanide 3-chlorophenyl hydrazone; DMEM: Dulbecco's modified eagle medium; EDTA: ethylene-diamine-tetra-acetic acid; EGFP: enhanced green fluorescent protein; EGTA: ethylene glycol bis(2-aminoethyl ether)tetraacetic acid; FUNDC1: FUN14 domain containing 1; HD: Huntington disease; HRP: horseradish peroxidase; HTT: huntingtin; LC3-II: lipidated form of MAP1LC3/LC3; mtDNA: mitochondrial deoxyribonucleic acid; MTDR: MitoTracker Deep Red; MTOR: mechanistic target of rapamycin kinase; MTORC1: mechanistic target of rapamycin kinase complex 1; NBR1: NBR1, autophagy cargo receptor; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; OCR: oxygen consumption rate; OPTN: optineurin; OXPHOS: oxidative phosphorylation; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; PIK3R4/VPS15: phosphoinositide-3-kinase regulatory subunit 4; PINK1: PTEN induced putative kinase 1; PLA: proximity ligation assay; PMSF: phenylmethylsulfonyl fluoride; polyQ: polyglutamine; PtdIns3K: phosphatidylinositol 3-kinase; ROS: reactive oxygen species; Rot: rotenone; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SEM: standard error of the mean; SQSTM1/p62: sequestosome 1; TMRM: tetramethylrhodamine methyl ester; UB: ubiquitin; ULK1: unc-51 like kinase 1.
Collapse
Affiliation(s)
- Sandra Franco-Iborra
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED)-Autonomous University of Barcelona, Barcelona, Spain
| | - Ainhoa Plaza-Zabala
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED)-Autonomous University of Barcelona, Barcelona, Spain
| | - Marta Montpeyo
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED)-Autonomous University of Barcelona, Barcelona, Spain
| | - David Sebastian
- Institute for Research in Biomedicine (IRB) - Diabetes and Associated Metabolic Diseases Networking Biomedical Research (CIBERDEM), Barcelona, Spain
| | - Miquel Vila
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED)-Autonomous University of Barcelona, Barcelona, Spain
- Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | - Marta Martinez-Vicente
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED)-Autonomous University of Barcelona, Barcelona, Spain
| |
Collapse
|
16
|
Gensbittel V, Kräter M, Harlepp S, Busnelli I, Guck J, Goetz JG. Mechanical Adaptability of Tumor Cells in Metastasis. Dev Cell 2020; 56:164-179. [PMID: 33238151 DOI: 10.1016/j.devcel.2020.10.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/18/2020] [Accepted: 10/16/2020] [Indexed: 12/12/2022]
Abstract
The most dangerous aspect of cancer lies in metastatic progression. Tumor cells will successfully form life-threatening metastases when they undergo sequential steps along a journey from the primary tumor to distant organs. From a biomechanics standpoint, growth, invasion, intravasation, circulation, arrest/adhesion, and extravasation of tumor cells demand particular cell-mechanical properties in order to survive and complete the metastatic cascade. With metastatic cells usually being softer than their non-malignant counterparts, high deformability for both the cell and its nucleus is thought to offer a significant advantage for metastatic potential. However, it is still unclear whether there is a finely tuned but fixed mechanical state that accommodates all mechanical features required for survival throughout the cascade or whether tumor cells need to dynamically refine their properties and intracellular components at each new step encountered. Here, we review the various mechanical requirements successful cancer cells might need to fulfill along their journey and speculate on the possibility that they dynamically adapt their properties accordingly. The mechanical signature of a successful cancer cell might actually be its ability to adapt to the successive microenvironmental constraints along the different steps of the journey.
Collapse
Affiliation(s)
- Valentin Gensbittel
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Martin Kräter
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Sébastien Harlepp
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Ignacio Busnelli
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
| | - Jochen Guck
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany.
| | - Jacky G Goetz
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France.
| |
Collapse
|
17
|
The Role of Vesicle Trafficking Defects in the Pathogenesis of Prion and Prion-Like Disorders. Int J Mol Sci 2020; 21:ijms21197016. [PMID: 32977678 PMCID: PMC7582986 DOI: 10.3390/ijms21197016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/15/2020] [Accepted: 09/21/2020] [Indexed: 11/26/2022] Open
Abstract
Prion diseases are fatal and transmissible neurodegenerative diseases in which the cellular form of the prion protein ‘PrPc’, misfolds into an infectious and aggregation prone isoform termed PrPSc, which is the primary component of prions. Many neurodegenerative diseases, like Alzheimer’s disease, Parkinson’s disease, and polyglutamine diseases, such as Huntington’s disease, are considered prion-like disorders because of the common characteristics in the propagation and spreading of misfolded proteins that they share with the prion diseases. Unlike prion diseases, these are non-infectious outside experimental settings. Many vesicular trafficking impairments, which are observed in prion and prion-like disorders, favor the accumulation of the pathogenic amyloid aggregates. In addition, many of the vesicular trafficking impairments that arise in these diseases, turn out to be further aggravating factors. This review offers an insight into the currently known vesicular trafficking defects in these neurodegenerative diseases and their implications on disease progression. These findings suggest that these impaired trafficking pathways may represent similar therapeutic targets in these classes of neurodegenerative disorders.
Collapse
|
18
|
Benito-Martínez S, Zhu Y, Jani RA, Harper DC, Marks MS, Delevoye C. Research Techniques Made Simple: Cell Biology Methods for the Analysis of Pigmentation. J Invest Dermatol 2020; 140:257-268.e8. [PMID: 31980058 DOI: 10.1016/j.jid.2019.12.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/27/2019] [Accepted: 12/05/2019] [Indexed: 12/11/2022]
Abstract
Pigmentation of the skin and hair represents the result of melanin biosynthesis within melanosomes of epidermal melanocytes, followed by the transfer of mature melanin granules to adjacent keratinocytes within the basal layer of the epidermis. Natural variation in these processes produces the diversity of skin and hair color among human populations, and defects in these processes lead to diseases such as oculocutaneous albinism. While genetic regulators of pigmentation have been well studied in human and animal models, we are still learning much about the cell biological features that regulate melanogenesis, melanosome maturation, and melanosome motility in melanocytes, and have barely scratched the surface in our understanding of melanin transfer from melanocytes to keratinocytes. Herein, we describe cultured cell model systems and common assays that have been used by investigators to dissect these features and that will hopefully lead to additional advances in the future.
Collapse
Affiliation(s)
- Silvia Benito-Martínez
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, Paris, France
| | - Yueyao Zhu
- Department of Biology Graduate Program, University of Pennsylvania, Philadelphia, Pennsylvania, USA; Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania, USA; Department of Pathology and Laboratory Medicine and Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Riddhi Atul Jani
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, Paris, France
| | - Dawn C Harper
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania, USA
| | - Michael S Marks
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, Pennsylvania, USA; Department of Pathology and Laboratory Medicine and Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
| | - Cédric Delevoye
- Structure and Membrane Compartments, Institut Curie, Paris Sciences & Lettres Research University, Centre National de la Recherche Scientifique, Paris, France.
| |
Collapse
|
19
|
Covarrubias-Pinto A, Parra AV, Mayorga-Weber G, Papic E, Vicencio I, Ehrenfeld P, Rivera FJ, Castro MA. Impaired intracellular trafficking of sodium-dependent vitamin C transporter 2 contributes to the redox imbalance in Huntington's disease. J Neurosci Res 2020; 99:223-235. [PMID: 32754987 DOI: 10.1002/jnr.24693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 06/10/2020] [Accepted: 06/27/2020] [Indexed: 12/18/2022]
Abstract
Huntington's disease (HD) is a neurodegenerative disorder caused by a glutamine expansion at the first exon of the huntingtin gene. Huntingtin protein (Htt) is ubiquitously expressed and it is localized in several organelles, including endosomes. HD is associated with a failure in energy metabolism and oxidative damage. Ascorbic acid is a powerful antioxidant highly concentrated in the brain where it acts as a messenger, modulating neuronal metabolism. It is transported into neurons via the sodium-dependent vitamin C transporter 2 (SVCT2). During synaptic activity, ascorbic acid is released from glial reservoirs to the extracellular space, inducing an increase in SVCT2 localization at the plasma membrane. Here, we studied SVCT2 trafficking and localization in HD. SVCT2 is decreased at synaptic terminals in YAC128 male mice. Using cellular models for HD (STHdhQ7 and STHdhQ111 cells), we determined that SVCT2 trafficking through secretory and endosomal pathways is altered in resting conditions. We observed Golgi fragmentation and SVCT2/Htt-associated protein-1 mis-colocalization. Additionally, we observed altered ascorbic acid-induced calcium signaling that explains the reduced SVCT2 translocation to the plasma membrane in the presence of extracellular ascorbic acid (active conditions) described in our previous results. Therefore, SVCT2 trafficking to the plasma membrane is altered in resting and active conditions in HD, explaining the redox imbalance observed during early stages of the disease.
Collapse
Affiliation(s)
- Adriana Covarrubias-Pinto
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Alejandra V Parra
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Gonzalo Mayorga-Weber
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Eduardo Papic
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Isidora Vicencio
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Pamela Ehrenfeld
- Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.,Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Francisco J Rivera
- Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.,Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Salzburg, Austria
| | - Maite A Castro
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.,Janelia Research Campus, HHMI, Ashburn, VA, USA
| |
Collapse
|
20
|
Traffic signaling: new functions of huntingtin and axonal transport in neurological disease. Curr Opin Neurobiol 2020; 63:122-130. [DOI: 10.1016/j.conb.2020.04.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/06/2020] [Accepted: 04/10/2020] [Indexed: 12/12/2022]
|
21
|
Wong CO. Endosomal-Lysosomal Processing of Neurodegeneration-Associated Proteins in Astrocytes. Int J Mol Sci 2020; 21:ijms21145149. [PMID: 32708198 PMCID: PMC7404029 DOI: 10.3390/ijms21145149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/17/2020] [Accepted: 07/18/2020] [Indexed: 12/15/2022] Open
Abstract
Most common neurodegenerative diseases (NDs) are characterized by deposition of protein aggregates that are resulted from misfolding, dysregulated trafficking, and compromised proteolytic degradation. These proteins exert cellular toxicity to a broad range of brain cells and are found in both neurons and glia. Extracellular monomeric and oligomeric ND-associated proteins are taken up by astrocytes, the most abundant glial cell in the brain. Internalization, intracellular trafficking, processing, and disposal of these proteins are executed by the endosomal-lysosomal system of astrocytes. Endosomal-lysosomal organelles thus mediate the cellular impact and metabolic fate of these toxic protein species. Given the indispensable role of astrocytes in brain metabolic homeostasis, the endosomal-lysosomal processing of these proteins plays a fundamental role in altering the trajectory of neurodegeneration. This review aims at summarizing the mounting evidence that has established the essential role of astrocytic endosomal-lysosomal organelles in the processing of amyloid precursor proteins, Apolipoprotein E (ApoE), tau, alpha synuclein, and huntingtin, which are associated with NDs such as Alzheimer’s, Parkinson’s, and Huntington diseases.
Collapse
Affiliation(s)
- Ching-On Wong
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
| |
Collapse
|
22
|
Taran AS, Shuvalova LD, Lagarkova MA, Alieva IB. Huntington's Disease-An Outlook on the Interplay of the HTT Protein, Microtubules and Actin Cytoskeletal Components. Cells 2020; 9:E1514. [PMID: 32580314 PMCID: PMC7348758 DOI: 10.3390/cells9061514] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 06/17/2020] [Accepted: 06/17/2020] [Indexed: 12/13/2022] Open
Abstract
Huntington's disease is a severe and currently incurable neurodegenerative disease. An autosomal dominant mutation in the Huntingtin gene (HTT) causes an increase in the polyglutamine fragment length at the protein N-terminus. The consequence of the mutation is the death of neurons, mostly striatal neurons, leading to the occurrence of a complex of motor, cognitive and emotional-volitional personality sphere disorders in carriers. Despite intensive studies, the functions of both mutant and wild-type huntingtin remain poorly understood. Surprisingly, there is the selective effect of the mutant form of HTT even on nervous tissue, whereas the protein is expressed ubiquitously. Huntingtin plays a role in cell physiology and affects cell transport, endocytosis, protein degradation and other cellular and molecular processes. Our experimental data mining let us conclude that a significant part of the Huntingtin-involved cellular processes is mediated by microtubules and other cytoskeletal cell structures. The review attempts to look at unresolved issues in the study of the huntingtin and its mutant form, including their functions affecting microtubules and other components of the cell cytoskeleton.
Collapse
Affiliation(s)
- Aleksandra S. Taran
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 1–73, Leninsky Gory, 119992 Moscow, Russia; (A.S.T.); (L.D.S.)
| | - Lilia D. Shuvalova
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 1–73, Leninsky Gory, 119992 Moscow, Russia; (A.S.T.); (L.D.S.)
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 1a Malaya Pirogovskaya St., 119435 Moscow, Russia
| | - Maria A. Lagarkova
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 1a Malaya Pirogovskaya St., 119435 Moscow, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 1a Malaya Pirogovskaya St., 119435 Moscow, Russia
| | - Irina B. Alieva
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 1a Malaya Pirogovskaya St., 119435 Moscow, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 1–40, Leninsky Gory, 119992 Moscow, Russia
| |
Collapse
|
23
|
Ba Q, Raghavan G, Kiselyov K, Yang G. Whole-Cell Scale Dynamic Organization of Lysosomes Revealed by Spatial Statistical Analysis. Cell Rep 2019; 23:3591-3606. [PMID: 29925001 DOI: 10.1016/j.celrep.2018.05.079] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 04/14/2018] [Accepted: 05/23/2018] [Indexed: 01/22/2023] Open
Abstract
In eukaryotic cells, lysosomes are distributed in the cytoplasm as individual membrane-bound compartments to degrade macromolecules and to control cellular metabolism. A fundamental yet unanswered question is whether and, if so, how individual lysosomes are organized spatially to coordinate and integrate their functions. To address this question, we analyzed their collective behavior in cultured cells using spatial statistical techniques. We found that in single cells, lysosomes maintain non-random, stable, yet distinct spatial distributions mediated by the cytoskeleton, the endoplasmic reticulum (ER), and lysosomal biogenesis. Throughout the intracellular space, lysosomes form dynamic clusters that significantly increase their interactions with endosomes. Cluster formation is associated with local increases in ER spatial density but does not depend on fusion with endosomes or spatial exclusion by mitochondria. Taken together, our findings reveal whole-cell scale spatial organization of lysosomes and provide insights into how organelle interactions are mediated and regulated across the entire intracellular space.
Collapse
Affiliation(s)
- Qinle Ba
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Guruprasad Raghavan
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Kirill Kiselyov
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Ge Yang
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| |
Collapse
|
24
|
van Bommel B, Konietzny A, Kobler O, Bär J, Mikhaylova M. F-actin patches associated with glutamatergic synapses control positioning of dendritic lysosomes. EMBO J 2019; 38:e101183. [PMID: 31267565 PMCID: PMC6669925 DOI: 10.15252/embj.2018101183] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 05/27/2019] [Accepted: 05/29/2019] [Indexed: 12/31/2022] Open
Abstract
Organelle positioning within neurites is required for proper neuronal function. In dendrites, with their complex cytoskeletal organization, transport of organelles is guided by local specializations of the microtubule and actin cytoskeleton, and by coordinated activity of different motor proteins. Here, we focus on the actin cytoskeleton in the dendritic shaft and describe dense structures consisting of longitudinal and branched actin filaments. These actin patches are devoid of microtubules and are frequently located at the base of spines, or form an actin mesh around excitatory shaft synapses. Using lysosomes as an example, we demonstrate that the presence of actin patches has a strong impact on dendritic organelle transport, as lysosomes frequently stall at these locations. We provide mechanistic insights on this pausing behavior, demonstrating that actin patches form a physical barrier for kinesin-driven cargo. In addition, we identify myosin Va as an active tether which mediates long-term stalling. This correlation between the presence of actin meshes and halting of organelles could be a generalized principle by which synapses control organelle trafficking.
Collapse
Affiliation(s)
- Bas van Bommel
- DFG Emmy Noether Group "Neuronal Protein Transport", Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anja Konietzny
- DFG Emmy Noether Group "Neuronal Protein Transport", Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Oliver Kobler
- Combinatorial Neuroimaging Core Facility (CNI), Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Julia Bär
- DFG Emmy Noether Group "Neuronal Protein Transport", Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marina Mikhaylova
- DFG Emmy Noether Group "Neuronal Protein Transport", Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
25
|
Chen C, Peng Y, Yen Y, Bhan P, Muthaiyan Shanmugam M, Klopfenstein DR, Wagner OI. Insights on UNC‐104‐dynein/dynactin interactions and their implications on axonal transport in
Caenorhabditis elegans. J Neurosci Res 2018; 97:185-201. [DOI: 10.1002/jnr.24339] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 09/18/2018] [Accepted: 09/18/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Chih‐Wei Chen
- Department of Life Science, Institute of Molecular and Cellular Biology National Tsing Hua University Hsinchu Taiwan
| | - Yu‐Fei Peng
- Department of Life Science, Institute of Molecular and Cellular Biology National Tsing Hua University Hsinchu Taiwan
| | - Ying‐Cheng Yen
- Department of Life Science, Institute of Molecular and Cellular Biology National Tsing Hua University Hsinchu Taiwan
| | - Prerana Bhan
- Department of Life Science, Institute of Molecular and Cellular Biology National Tsing Hua University Hsinchu Taiwan
| | - Muniesh Muthaiyan Shanmugam
- Department of Life Science, Institute of Molecular and Cellular Biology National Tsing Hua University Hsinchu Taiwan
| | | | - Oliver I. Wagner
- Department of Life Science, Institute of Molecular and Cellular Biology National Tsing Hua University Hsinchu Taiwan
| |
Collapse
|
26
|
Danson CM, Pearson N, Heesom KJ, Cullen PJ. Sorting nexin-21 is a scaffold for the endosomal recruitment of huntingtin. J Cell Sci 2018; 131:jcs.211672. [PMID: 30072438 PMCID: PMC6140323 DOI: 10.1242/jcs.211672] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 07/23/2018] [Indexed: 12/17/2022] Open
Abstract
The endo-lysosomal network serves an essential role in determining the fate of endocytosed transmembrane proteins and their associated proteins and lipids. Sorting nexins (SNXs) play a central role in the functional organisation of this network. Comprising over 30 proteins in humans, SNXs are classified into sub-groups based on the presence of additional functional domains. Sorting nexin-20 (SNX20) and sorting nexin-21 (SNX21) comprise the SNX-PXB proteins. The presence of a predicted protein-protein interaction domain, termed the PX-associated B (PXB) domain, has led to the proposal that they function as endosome-associated scaffolds. Here, we used unbiased quantitative proteomics to define the SNX21 interactome. We reveal that the N-terminal extension of SNX21 interacts with huntingtin (Htt) whereas the PXB domain appears to associate with septins, a family of cytoskeletal- and membrane-associated proteins. In establishing that these interactions are sufficient for SNX21 to recruit Htt and septins on to an endosomal population, we reveal a scaffolding function for this sorting nexin. Our work paves the way for a more-detailed mechanistic analysis of the role(s) of the SNX-PXB proteins in endosomal biology. Summary: A potential scaffolding function for SNX21 paves the way for a more-detailed mechanistic analysis of the role(s) of this protein in endosomal biology.
Collapse
Affiliation(s)
- Chris M Danson
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Neil Pearson
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Kate J Heesom
- Proteomics Facility, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Peter J Cullen
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| |
Collapse
|
27
|
Yu Y, Xiong Y, Montani JP, Yang Z, Ming XF. Arginase-II activates mTORC1 through myosin-1b in vascular cell senescence and apoptosis. Cell Death Dis 2018; 9:313. [PMID: 29472548 PMCID: PMC5833809 DOI: 10.1038/s41419-018-0356-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/24/2018] [Accepted: 01/26/2018] [Indexed: 11/21/2022]
Abstract
Type-II L-arginine:ureahydrolase, arginase-II (Arg-II), is shown to activate mechanistic target of rapamycin complex 1 (mTORC1) pathway and contributes to cell senescence and apoptosis. In an attempt to elucidate the underlying mechanism, we identified myosin-1b (Myo1b) as a mediator. Overexpression of Arg-II induces re-distribution of lysosome and mTOR but not of tuberous sclerosis complex (TSC) from perinuclear area to cell periphery, dissociation of TSC from lysosome and activation of mTORC1-ribosomal protein S6 kinase 1 (S6K1) pathway. Silencing Myo1b prevents all these alterations induced by Arg-II. By overexpressing Myo1b or its mutant with point mutation in its pleckstrin homology (PH) domain we further demonstrate that this effect of Myo1b is dependent on its PH domain that is required for Myo1b-lysosome association. Notably, Arg-II promotes association of Myo1b with lysosomes. In addition, we show that in senescent vascular smooth muscle cells with elevated endogenous Arg-II, silencing Myo1b prevents Arg-II-mediated lysosomal positioning, dissociation of TSC from lysosome, mTORC1 activation and cell apoptosis. Taken together, our study demonstrates that Myo1b mediates the effect of Arg-II in activating mTORC1-S6K1 through promoting peripheral lysosomal positioning, that results in spatial separation and thus dissociation of TSC from lysosome, leading to hyperactive mTORC1-S6K1 signaling linking to cellular senescence/apoptosis.
Collapse
Affiliation(s)
- Yi Yu
- Cardiovascular and Aging Research, Department of Medicine, Division of Physiology, University of Fribourg, Chemin du Musée 5, 1700, Fribourg, Switzerland
| | - Yuyan Xiong
- Cardiovascular and Aging Research, Department of Medicine, Division of Physiology, University of Fribourg, Chemin du Musée 5, 1700, Fribourg, Switzerland
| | - Jean-Pierre Montani
- Cardiovascular and Aging Research, Department of Medicine, Division of Physiology, University of Fribourg, Chemin du Musée 5, 1700, Fribourg, Switzerland.,National Center of Competence in Research "Kidney.CH", Zurich, Switzerland
| | - Zhihong Yang
- Cardiovascular and Aging Research, Department of Medicine, Division of Physiology, University of Fribourg, Chemin du Musée 5, 1700, Fribourg, Switzerland. .,National Center of Competence in Research "Kidney.CH", Zurich, Switzerland.
| | - Xiu-Fen Ming
- Cardiovascular and Aging Research, Department of Medicine, Division of Physiology, University of Fribourg, Chemin du Musée 5, 1700, Fribourg, Switzerland. .,National Center of Competence in Research "Kidney.CH", Zurich, Switzerland.
| |
Collapse
|
28
|
Chen XQ, Sawa M, Mobley WC. Dysregulation of neurotrophin signaling in the pathogenesis of Alzheimer disease and of Alzheimer disease in Down syndrome. Free Radic Biol Med 2018; 114:52-61. [PMID: 29031834 PMCID: PMC5748266 DOI: 10.1016/j.freeradbiomed.2017.10.341] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/05/2017] [Accepted: 10/10/2017] [Indexed: 12/15/2022]
Abstract
Neurotrophic factors, including the members of the neurotrophin family, play important roles in the development and maintenance of the nervous system. Trophic factor signals must be transmitted over long distances from axons and dendrites to the cell bodies of neurons. A mode of signaling well suited to the challenge of robust long distance signaling is the signaling endosome. We review the biology of signaling endosomes and the "signaling endosome hypothesis". Evidence for disruption of signaling endosome function in disorders of the nervous system is also reviewed. Changes in endosome structure in Alzheimer disease (AD) and Down syndrome (DS) are present early in these disorders. Data for the APP products responsible are reviewed and the consequent changes in signaling from endosomes discussed. We conclude by pointing to the need for additional studies to explore the biology of signaling endosomes in normal neurons and to elucidate their role in the pathogenesis of neurodegeneration.
Collapse
Affiliation(s)
- Xu-Qiao Chen
- University of California, San Diego, La Jolla, CA 92093, United States.
| | - Mariko Sawa
- University of California, San Diego, La Jolla, CA 92093, United States
| | - William C Mobley
- University of California, San Diego, La Jolla, CA 92093, United States.
| |
Collapse
|
29
|
Terenzio M, Schiavo G, Fainzilber M. Compartmentalized Signaling in Neurons: From Cell Biology to Neuroscience. Neuron 2017; 96:667-679. [PMID: 29096079 DOI: 10.1016/j.neuron.2017.10.015] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 09/27/2017] [Accepted: 10/09/2017] [Indexed: 12/18/2022]
Abstract
Neurons are the largest known cells, with complex and highly polarized morphologies. As such, neuronal signaling is highly compartmentalized, requiring sophisticated transfer mechanisms to convey and integrate information within and between sub-neuronal compartments. Here, we survey different modes of compartmentalized signaling in neurons, highlighting examples wherein the fundamental cell biological processes of protein synthesis and degradation, membrane trafficking, and organelle transport are employed to enable the encoding and integration of information, locally and globally within a neuron. Comparisons to other cell types indicate that neurons accentuate widely shared mechanisms, providing invaluable models for the compartmentalization and transfer mechanisms required and used by most eukaryotic cells.
Collapse
Affiliation(s)
- Marco Terenzio
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Giampietro Schiavo
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, London WC1N 3BG, UK; Discoveries Centre for Regenerative and Precision Medicine at UCL, London WC1N 3BG, UK; UK Dementia Research Institute at UCL, London WC1E 6BT, UK
| | - Mike Fainzilber
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
| |
Collapse
|
30
|
Duclos C, Lavoie C, Denault JB. Caspases rule the intracellular trafficking cartel. FEBS J 2017; 284:1394-1420. [PMID: 28371378 DOI: 10.1111/febs.14071] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 03/17/2017] [Accepted: 03/27/2017] [Indexed: 12/15/2022]
Abstract
During apoptosis, caspases feast on several hundreds of cellular proteins to orchestrate rapid cellular demise. Indeed, caspases are known to get a taste of every cellular process in one way or another, activating some, but most often shutting them down. Thus, it is not surprising that caspases proteolyze proteins involved in intracellular trafficking with particularly devastating consequences for this important process. This review article focuses on how caspases target the machinery responsible for smuggling goods within and outside the cell.
Collapse
Affiliation(s)
- Catherine Duclos
- Institut de Pharmacologie de Sherbrooke, Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, QC, Canada
| | - Christine Lavoie
- Institut de Pharmacologie de Sherbrooke, Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, QC, Canada
| | - Jean-Bernard Denault
- Institut de Pharmacologie de Sherbrooke, Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, QC, Canada
| |
Collapse
|
31
|
Liu JJ. Regulation of dynein-dynactin-driven vesicular transport. Traffic 2017; 18:336-347. [PMID: 28248450 DOI: 10.1111/tra.12475] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 02/22/2017] [Accepted: 02/22/2017] [Indexed: 01/01/2023]
Abstract
Most of the long-range intracellular movements of vesicles, organelles and other cargoes are driven by microtubule (MT)-based molecular motors. Cytoplasmic dynein, a multisubunit protein complex, with the aid of dynactin, drives transport of a wide variety of cargoes towards the minus end of MTs. In this article, I review our current understanding of the mechanisms underlying spatiotemporal regulation of dynein-dynactin-driven vesicular transport with a special emphasis on the many steps of directional movement along MT tracks. These include the recruitment of dynein to MT plus ends, the activation and processivity of dynein, and cargo recognition and release by the motor complex at the target membrane. Furthermore, I summarize the most recent findings about the fine control mechanisms for intracellular transport via the interaction between the dynein-dynactin motor complex and its vesicular cargoes.
Collapse
Affiliation(s)
- Jia-Jia Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
32
|
Neefjes J, Jongsma MML, Berlin I. Stop or Go? Endosome Positioning in the Establishment of Compartment Architecture, Dynamics, and Function. Trends Cell Biol 2017; 27:580-594. [PMID: 28363667 DOI: 10.1016/j.tcb.2017.03.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/03/2017] [Accepted: 03/06/2017] [Indexed: 02/03/2023]
Abstract
The endosomal system constitutes a key negotiator between the environment of a cell and its internal affairs. Comprised of a complex membranous network, wherein each vesicle can in principle move autonomously throughout the cell, the endosomal system operates as a coherent unit to optimally face external challenges and maintain homeostasis. Our appreciation of how individual endosomes are controlled in time and space to best serve their collective purpose has evolved dramatically in recent years. In light of these efforts, the endoplasmic reticulum (ER) - with its expanse of membranes permeating the cytoplasmic space - has emerged as a potent spatiotemporal organizer of endosome biology. We review the latest advances in our understanding of the mechanisms underpinning endosomal transport and positioning, with emphasis on the contributions from the ER, and offer a perspective on how the interplay between these aspects shapes the architecture and dynamics of the endosomal system and drives its myriad cellular functions.
Collapse
Affiliation(s)
- Jacques Neefjes
- Department of Chemical Immunology, Leiden University Medical Center (LUMC), Einthovenweg 20, 2333 ZC Leiden, The Netherlands
| | - Marlieke M L Jongsma
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center (AMC)/Universiteit van Amsterdam (UvA), Plesmanlaan 125, 1066 CX Amsterdam, The Netherlands
| | - Ilana Berlin
- Department of Chemical Immunology, Leiden University Medical Center (LUMC), Einthovenweg 20, 2333 ZC Leiden, The Netherlands.
| |
Collapse
|
33
|
Martinez-Vicente M. Neuronal Mitophagy in Neurodegenerative Diseases. Front Mol Neurosci 2017; 10:64. [PMID: 28337125 PMCID: PMC5340781 DOI: 10.3389/fnmol.2017.00064] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 02/24/2017] [Indexed: 01/01/2023] Open
Abstract
Neuronal homeostasis depends on the proper functioning of different quality control systems. All intracellular components are subjected to continuous turnover through the coordinated synthesis, degradation and recycling of their constituent elements. Autophagy is the catabolic mechanism by which intracellular cytosolic components, including proteins, organelles, aggregates and any other intracellular materials, are delivered to lysosomes for degradation. Among the different types of selective autophagy described to date, the process of mitophagy involves the selective autophagic degradation of mitochondria. In this way, mitophagy is responsible for basal mitochondrial turnover, but can also be induced under certain physiological or pathogenic conditions to eliminate unwanted or damaged mitochondria. Dysfunctional cellular proteolytic systems have been linked extensively to neurodegenerative diseases (ND) like Alzheimer’s disease (AD), Parkinson’s disease (PD), or Huntington’s disease (HD), with autophagic failure being one of the main factors contributing to neuronal cell death in these diseases. Neurons are particularly vulnerable to autophagic impairment as well as to mitochondrial dysfunction, due mostly to their particular high energy dependence and to their post-mitotic nature. The accurate and proper degradation of dysfunctional mitochondria by mitophagy is essential for maintaining control over mitochondrial quality and quantity in neurons. In this report, I will review the role of mitophagy in neuronal homeostasis and the consequences of its dysfunction in ND.
Collapse
Affiliation(s)
- Marta Martinez-Vicente
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research InstituteBarcelona, Spain; Autonomous University of Barcelona (UAB)Barcelona, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED)Barcelona, Spain
| |
Collapse
|
34
|
Bulgari D, Deitcher DL, Levitan ES. Loss of Huntingtin stimulates capture of retrograde dense-core vesicles to increase synaptic neuropeptide stores. Eur J Cell Biol 2017; 96:402-406. [PMID: 28129919 DOI: 10.1016/j.ejcb.2017.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 12/23/2016] [Accepted: 01/04/2017] [Indexed: 02/03/2023] Open
Abstract
The Huntington's disease protein Huntingtin (Htt) regulates axonal transport of dense-core vesicles (DCVs) containing neurotrophins and neuropeptides. DCVs travel down axons to reach nerve terminals where they are either captured in synaptic boutons to support later release or reverse direction to reenter the axon as part of vesicle circulation. Currently, the impact of Htt on DCV dynamics in the terminal is unknown. Here we report that knockout of Drosophila Htt selectively reduces retrograde DCV flux at proximal boutons of motoneuron terminals. However, initiation of retrograde transport at the most distal bouton and transport velocity are unaffected suggesting that synaptic capture rate of these retrograde DCVs could be altered. In fact, tracking DCVs shows that retrograde synaptic capture efficiency is significantly elevated by Htt knockout or knockdown. Furthermore, synaptic boutons contain more neuropeptide in Htt knockout larvae even though bouton size, single DCV fluorescence intensity, neuropeptide release in response to electrical stimulation and subsequent activity-dependent capture are unaffected. Thus, loss of Htt increases synaptic capture as DCVs travel by retrograde transport through boutons resulting in reduced transport toward the axon and increased neuropeptide in the terminal. These results therefore identify native Htt as a regulator of synaptic capture and neuropeptide storage.
Collapse
Affiliation(s)
- Dinara Bulgari
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - David L Deitcher
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA
| | - Edwin S Levitan
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA.
| |
Collapse
|
35
|
|
36
|
Pu J, Guardia CM, Keren-Kaplan T, Bonifacino JS. Mechanisms and functions of lysosome positioning. J Cell Sci 2016; 129:4329-4339. [PMID: 27799357 DOI: 10.1242/jcs.196287] [Citation(s) in RCA: 276] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Lysosomes have been classically considered terminal degradative organelles, but in recent years they have been found to participate in many other cellular processes, including killing of intracellular pathogens, antigen presentation, plasma membrane repair, cell adhesion and migration, tumor invasion and metastasis, apoptotic cell death, metabolic signaling and gene regulation. In addition, lysosome dysfunction has been shown to underlie not only rare lysosome storage disorders but also more common diseases, such as cancer and neurodegeneration. The involvement of lysosomes in most of these processes is now known to depend on the ability of lysosomes to move throughout the cytoplasm. Here, we review recent findings on the mechanisms that mediate the motility and positioning of lysosomes, and the importance of lysosome dynamics for cell physiology and pathology.
Collapse
Affiliation(s)
- Jing Pu
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Carlos M Guardia
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tal Keren-Kaplan
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Juan S Bonifacino
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| |
Collapse
|
37
|
Fujiwara T, Ye S, Castro-Gomes T, Winchell CG, Andrews NW, Voth DE, Varughese KI, Mackintosh SG, Feng Y, Pavlos N, Nakamura T, Manolagas SC, Zhao H. PLEKHM1/DEF8/RAB7 complex regulates lysosome positioning and bone homeostasis. JCI Insight 2016; 1:e86330. [PMID: 27777970 DOI: 10.1172/jci.insight.86330] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Mutations of the Plekhm1 gene in humans and rats cause osteopetrosis, an inherited bone disease characterized by diminished bone resorption by osteoclasts. PLEKHM1 binds to RAB7 and is critical for lysosome trafficking. However, the molecular mechanisms by which PLEKHM1 regulates lysosomal pathways remain unknown. Here, we generated germline and conditional Plekhm1-deficient mice. These mice displayed no overt abnormalities in major organs, except for an increase in trabecular bone mass. Furthermore, loss of PLEKHM1 abrogated the peripheral distribution of lysosomes and bone resorption in osteoclasts. Mechanistically, we indicated that DEF8 interacts with PLEKHM1 and promotes its binding to RAB7, whereas the binding of FAM98A and NDEL1 with PLEKHM1 connects lysosomes to microtubules. Importantly, suppression of these proteins results in lysosome positioning and bone resorption defects similar to those of Plekhm1-null osteoclasts. Thus, PLHKEM1, DEF8, FAM98A, and NDEL1 constitute a molecular complex that regulates lysosome positioning and secretion through RAB7.
Collapse
Affiliation(s)
- Toshifumi Fujiwara
- Center for Osteoporosis and Metabolic Bone Diseases, Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Shiqiao Ye
- Center for Osteoporosis and Metabolic Bone Diseases, Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Thiago Castro-Gomes
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
| | | | - Norma W Andrews
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
| | | | | | - Samuel G Mackintosh
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Yunfeng Feng
- Department of Pathology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, USA
| | - Nathan Pavlos
- Center for Orthopedic Research, Dentistry and Health Sciences, The University of Western Australia, Nedlands, Western Australia, Australia
| | - Takashi Nakamura
- Department of Biochemistry & Integrative Medical Biology, School of Medicine, Keio University, Tokyo, Japan
| | - Stavros C Manolagas
- Center for Osteoporosis and Metabolic Bone Diseases, Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Haibo Zhao
- Center for Osteoporosis and Metabolic Bone Diseases, Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.,Department of Physiology and Biophysics, and
| |
Collapse
|
38
|
East DA, Campanella M. Mitophagy and the therapeutic clearance of damaged mitochondria for neuroprotection. Int J Biochem Cell Biol 2016; 79:382-387. [DOI: 10.1016/j.biocel.2016.08.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 08/20/2016] [Indexed: 12/23/2022]
|
39
|
TRiC subunits enhance BDNF axonal transport and rescue striatal atrophy in Huntington's disease. Proc Natl Acad Sci U S A 2016; 113:E5655-64. [PMID: 27601642 DOI: 10.1073/pnas.1603020113] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Corticostriatal atrophy is a cardinal manifestation of Huntington's disease (HD). However, the mechanism(s) by which mutant huntingtin (mHTT) protein contributes to the degeneration of the corticostriatal circuit is not well understood. We recreated the corticostriatal circuit in microfluidic chambers, pairing cortical and striatal neurons from the BACHD model of HD and its WT control. There were reduced synaptic connectivity and atrophy of striatal neurons in cultures in which BACHD cortical and striatal neurons were paired. However, these changes were prevented if WT cortical neurons were paired with BACHD striatal neurons; synthesis and release of brain-derived neurotrophic factor (BDNF) from WT cortical axons were responsible. Consistent with these findings, there was a marked reduction in anterograde transport of BDNF in BACHD cortical neurons. Subunits of the cytosolic chaperonin T-complex 1 (TCP-1) ring complex (TRiC or CCT for chaperonin containing TCP-1) have been shown to reduce mHTT levels. Both CCT3 and the apical domain of CCT1 (ApiCCT1) decreased the level of mHTT in BACHD cortical neurons. In cortical axons, they normalized anterograde BDNF transport, restored retrograde BDNF transport, and normalized lysosomal transport. Importantly, treating BACHD cortical neurons with ApiCCT1 prevented BACHD striatal neuronal atrophy by enhancing release of BDNF that subsequently acts through tyrosine receptor kinase B (TrkB) receptor on striatal neurons. Our findings are evidence that TRiC reagent-mediated reductions in mHTT enhanced BDNF delivery to restore the trophic status of BACHD striatal neurons.
Collapse
|
40
|
Load-induced enhancement of Dynein force production by LIS1-NudE in vivo and in vitro. Nat Commun 2016; 7:12259. [PMID: 27489054 PMCID: PMC4976208 DOI: 10.1038/ncomms12259] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 06/15/2016] [Indexed: 01/01/2023] Open
Abstract
Most sub-cellular cargos are transported along microtubules by kinesin and dynein molecular motors, but how transport is regulated is not well understood. It is unknown whether local control is possible, for example, by changes in specific cargo-associated motor behaviour to react to impediments. Here we discover that microtubule-associated lipid droplets (LDs) in COS1 cells respond to an optical trap with a remarkable enhancement in sustained force production. This effect is observed only for microtubule minus-end-moving LDs. It is specifically blocked by RNAi for the cytoplasmic dynein regulators LIS1 and NudE/L (Nde1/Ndel1), but not for the dynactin p150Glued subunit. It can be completely replicated using cell-free preparations of purified LDs, where duration of LD force production is more than doubled. These results identify a novel, intrinsic, cargo-associated mechanism for dynein-mediated force adaptation, which should markedly improve the ability of motor-driven cargoes to overcome subcellular obstacles. Transport of large cargo through the cytoplasm can encounter physical impediments which should be overcome. Here the authors show that lipid droplets constrained by an optical trap respond with an increase in dynein-mediated force that is dependent on dynein regulators LIS1 and NudE/L, but not on p150glued.
Collapse
|
41
|
Abstract
Polyglutamine (polyQ) expansion within Huntingtin (Htt) causes the fatal neurodegenerative disorder Huntington’s Disease (HD). Although Htt is ubiquitously expressed and conserved from Drosophila to humans, its normal biological function is still being elucidated. Here we characterize a role for the Drosophila Htt homolog (dHtt) in fast axonal transport (FAT). Generation and expression of transgenic dHtt-mRFP and human Htt-mRFP fusion proteins in Drosophila revealed co-localization with mitochondria and synaptic vesicles undergoing FAT. However, Htt was not ubiquitously associated with the transport machinery, as it was excluded from dense-core vesicles and APLIP1 containing vesicles. Quantification of cargo movement in dHtt deficient axons revealed that mitochondria and synaptic vesicles show a decrease in the distance and duration of transport, and an increase in the number of pauses. In addition, the ratio of retrograde to anterograde flux was increased in mutant animals. Densecore vesicles did not display similar defects in processivity, but did show altered retrograde to anterograde flux along axons. Given the co-localization with mitochondria and synaptic vesicles, but not dense-core vesicles, the data suggest dHtt likely acts locally at cargo interaction sites to regulate processivity. An increase in dynein heavy chain expression was also observed in dHtt mutants, suggesting that the altered flux observed for all cargo may represent secondary transport changes occurring independent of dHtt’s primary function. Expression of dHtt in a milton (HAP1) mutant background revealed that the protein does not require mitochondria or HAP1 to localize along axons, suggesting Htt has an independent mechanism for coupling with motors to regulate their processivity during axonal transport.
Collapse
Affiliation(s)
- Kurt R Weiss
- a Department of Biology , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA.,b Department of Brain and Cognitive Sciences , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA
| | - J Troy Littleton
- a Department of Biology , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA.,b Department of Brain and Cognitive Sciences , The Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge , MA , USA
| |
Collapse
|
42
|
Ito K, Enomoto H. Retrograde transport of neurotrophic factor signaling: implications in neuronal development and pathogenesis. J Biochem 2016; 160:77-85. [DOI: 10.1093/jb/mvw037] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 05/21/2016] [Indexed: 12/25/2022] Open
|
43
|
Vilmont V, Cadot B, Vezin E, Le Grand F, Gomes ER. Dynein disruption perturbs post-synaptic components and contributes to impaired MuSK clustering at the NMJ: implication in ALS. Sci Rep 2016; 6:27804. [PMID: 27283349 PMCID: PMC4901269 DOI: 10.1038/srep27804] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 05/20/2016] [Indexed: 12/13/2022] Open
Abstract
The neuromuscular junction (NMJ) allows the transformation of a neuronal message into a mechanical force by muscle contraction and is the target of several neuromuscular disorders. While the neuronal side is under extensive research, the muscle appeared recently to have a growing role in the formation and integrity of the neuromuscular junction. We used an in vitro model of mature myofibers to study the role of dynein on major postsynaptic proteins. We found that dynein affects the expression and the clustering of acetylcholine receptors (AChRs), muscle specific tyrosine kinase (MuSK) and Rapsyn. We also show that myofibers with dynein impairment or from an amyotrophic lateral sclerosis (ALS) model (SOD1G93A) show similar defects in myofiber formation and agrin-induced AChR clustering suggesting a role for dynein impairment in ALS progression. Finally, we found that dynein can affect MuSK traffic through the endosomal pathway. Collectively, our studies show that defects in dynein can lead to impairment of muscle NMJ components’ expression and clustering. We propose that NMJ defects could happen via defective MuSK traffic and that this could be one of the pathological features involved in neurodegeneration such as ALS.
Collapse
Affiliation(s)
- Valérie Vilmont
- Myology Research Center, UM76-INSERM U974-CNRS FRE 3617 Sorbonne Universités, UPMC Université Paris 06, Paris, France
| | - Bruno Cadot
- Myology Research Center, UM76-INSERM U974-CNRS FRE 3617 Sorbonne Universités, UPMC Université Paris 06, Paris, France
| | - Elsa Vezin
- Myology Research Center, UM76-INSERM U974-CNRS FRE 3617 Sorbonne Universités, UPMC Université Paris 06, Paris, France
| | - Fabien Le Grand
- Myology Research Center, UM76-INSERM U974-CNRS FRE 3617 Sorbonne Universités, UPMC Université Paris 06, Paris, France
| | - Edgar R Gomes
- Myology Research Center, UM76-INSERM U974-CNRS FRE 3617 Sorbonne Universités, UPMC Université Paris 06, Paris, France.,Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| |
Collapse
|
44
|
Wijdeven RH, Janssen H, Nahidiazar L, Janssen L, Jalink K, Berlin I, Neefjes J. Cholesterol and ORP1L-mediated ER contact sites control autophagosome transport and fusion with the endocytic pathway. Nat Commun 2016; 7:11808. [PMID: 27283760 PMCID: PMC4906411 DOI: 10.1038/ncomms11808] [Citation(s) in RCA: 158] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/03/2016] [Indexed: 02/06/2023] Open
Abstract
Autophagy is the main homeostatic pathway guiding cytosolic materials for degradation by the lysosome. Maturation of autophagosomes requires their transport towards the perinuclear region of the cell, with key factors underlying both processes still poorly understood. Here we show that transport and positioning of late autophagosomes depends on cholesterol by way of the cholesterol-sensing Rab7 effector ORP1L. ORP1L localizes to late autophagosomes and—under low-cholesterol conditions—contacts the ER protein VAP-A, forming ER-autophagosome contact sites, which prevent minus-end transport by the Rab7–RILP–dynein complex. ORP1L-mediated contact sites also inhibit localization of PLEKHM1 to Rab7. PLEKHM1, together with RILP, then recruits the homotypic fusion and vacuole protein-sorting (HOPS) complex for fusion of autophagosomes with late endosomes and lysosomes. Thus, ORP1L, via its liganding by lipids and the formation of contacts between autophagic vacuoles and the ER, governs the last steps in autophagy that lead to the lysosomal degradation of cytosolic material. Autophagy requires transport of autophagosomes to the perinuclear region. Here, the authors show that ORP1L localizes to autophagosomes and mediates formation of ER contact sites that prevent autophagosome transport and fusion with endocytic vesicles when cholesterol levels are low.
Collapse
Affiliation(s)
- Ruud H Wijdeven
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Hans Janssen
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Leila Nahidiazar
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Lennert Janssen
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.,Department of Chemical Immunology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| | - Kees Jalink
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Ilana Berlin
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.,Department of Chemical Immunology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| | - Jacques Neefjes
- Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.,Department of Chemical Immunology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| |
Collapse
|
45
|
N-terminal Huntingtin Knock-In Mice: Implications of Removing the N-terminal Region of Huntingtin for Therapy. PLoS Genet 2016; 12:e1006083. [PMID: 27203582 PMCID: PMC4874551 DOI: 10.1371/journal.pgen.1006083] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/04/2016] [Indexed: 02/07/2023] Open
Abstract
The Huntington’s disease (HD) protein, huntingtin (HTT), is a large protein consisting of 3144 amino acids and has conserved N-terminal sequences that are followed by a polyglutamine (polyQ) repeat. Loss of Htt is known to cause embryonic lethality in mice, whereas polyQ expansion leads to adult neuronal degeneration. Whether N-terminal HTT is essential for neuronal development or contributes only to late-onset neurodegeneration remains unknown. We established HTT knock-in mice (N160Q-KI) expressing the first 208 amino acids of HTT with 160Q, and they show age-dependent HTT aggregates in the brain and neurological phenotypes. Importantly, the N-terminal mutant HTT also preferentially accumulates in the striatum, the brain region most affected in HD, indicating the importance of N-terminal HTT in selective neuropathology. That said, homozygous N160Q-KI mice are also embryonic lethal, suggesting that N-terminal HTT alone is unable to support embryonic development. Using Htt knockout neurons, we found that loss of Htt selectively affects the survival of developing neuronal cells, but not astrocytes, in culture. This neuronal degeneration could be rescued by a truncated HTT lacking the first 237 amino acids, but not by N-terminal HTT (1–208 amino acids). Also, the rescue effect depends on the region in HTT known to be involved in intracellular trafficking. Thus, the N-terminal HTT region may not be essential for the survival of developing neurons, but when carrying a large polyQ repeat, can cause selective neuropathology. These findings imply a possible therapeutic benefit of removing the N-terminal region of HTT containing the polyQ repeat to treat the neurodegeneration in HD. The 17 amino acids in the N-terminal region of huntingtin (HTT) are conserved in a wide range of species and are followed by a polyglutamine repeat whose expansion causes selective neurodegeneration in Huntington’s disease (HD). Loss of Htt can affect developing neurons and early embryonic development in mice. Whether N-terminal HTT is important for the survival of developing neurons or contributes mainly to a gain of toxic function in HD remains unknown. In the current study, we generated N-terminal mutant HTT knock-in mice and found that N-terminal HTT with an expanded polyQ repeat is unable to support the early development of mice, but can cause age-dependent neurological phenotypes. Further, we show that a truncated HTT without the N-terminal region can rescue the Htt loss-mediated degeneration of developing neurons. Our studies suggest that removal of the N-terminal region of mutant HTT could be a strategy to abolish the neuronal toxicity of mutant HTT.
Collapse
|
46
|
Starling GP, Yip YY, Sanger A, Morton PE, Eden ER, Dodding MP. Folliculin directs the formation of a Rab34-RILP complex to control the nutrient-dependent dynamic distribution of lysosomes. EMBO Rep 2016; 17:823-41. [PMID: 27113757 PMCID: PMC4893818 DOI: 10.15252/embr.201541382] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 03/14/2016] [Indexed: 11/09/2022] Open
Abstract
The spatial distribution of lysosomes is important for their function and is, in part, controlled by cellular nutrient status. Here, we show that the lysosome associated Birt-Hoge-Dubé (BHD) syndrome renal tumour suppressor folliculin (FLCN) regulates this process. FLCN promotes the peri-nuclear clustering of lysosomes following serum and amino acid withdrawal and is supported by the predominantly Golgi-associated small GTPase Rab34. Rab34-positive peri-nuclear membranes contact lysosomes and cause a reduction in lysosome motility and knockdown of FLCN inhibits Rab34-induced peri-nuclear lysosome clustering. FLCN interacts directly via its C-terminal DENN domain with the Rab34 effector RILP Using purified recombinant proteins, we show that the FLCN-DENN domain does not act as a GEF for Rab34, but rather, loads active Rab34 onto RILP We propose a model whereby starvation-induced FLCN association with lysosomes drives the formation of contact sites between lysosomes and Rab34-positive peri-nuclear membranes that restrict lysosome motility and thus promote their retention in this region of the cell.
Collapse
Affiliation(s)
- Georgina P Starling
- Randall Division of Cell and Molecular Biophysics, King's College London, London, UK
| | - Yan Y Yip
- Randall Division of Cell and Molecular Biophysics, King's College London, London, UK
| | - Anneri Sanger
- Randall Division of Cell and Molecular Biophysics, King's College London, London, UK
| | - Penny E Morton
- Randall Division of Cell and Molecular Biophysics, King's College London, London, UK
| | - Emily R Eden
- Institute of Ophthalmology, University College London, London, UK
| | - Mark P Dodding
- Randall Division of Cell and Molecular Biophysics, King's College London, London, UK
| |
Collapse
|
47
|
|
48
|
Hämälistö S, Jäättelä M. Lysosomes in cancer-living on the edge (of the cell). Curr Opin Cell Biol 2016; 39:69-76. [PMID: 26921697 DOI: 10.1016/j.ceb.2016.02.009] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/03/2016] [Accepted: 02/04/2016] [Indexed: 12/25/2022]
Abstract
The lysosomes have definitely polished their status inside the cell. Being discovered as the last resort of discarded cellular biomass, the steady rising of this versatile signaling organelle is currently ongoing. This review discusses the recent data on the unconventional functions of lysosomes, focusing mainly on the less studied lysosomes residing in the cellular periphery. We emphasize our discussion on the emerging paths the lysosomes have taken in promoting cancer progression to metastatic disease. Finally, we address how the altered cancerous lysosomes in metastatic cancers may be specifically targeted and what are the pending questions awaiting for elucidation.
Collapse
Affiliation(s)
- Saara Hämälistö
- Cell Death and Metabolism Unit, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - Marja Jäättelä
- Cell Death and Metabolism Unit, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark.
| |
Collapse
|
49
|
White JA, Anderson E, Zimmerman K, Zheng KH, Rouhani R, Gunawardena S. Huntingtin differentially regulates the axonal transport of a sub-set of Rab-containing vesicles in vivo. Hum Mol Genet 2015; 24:7182-95. [PMID: 26450517 DOI: 10.1093/hmg/ddv415] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/28/2015] [Indexed: 11/14/2022] Open
Abstract
Loss of huntingtin (HTT), the Huntington's disease (HD) protein, was previously shown to cause axonal transport defects. Within axons, HTT can associate with kinesin-1 and dynein motors either directly or via accessory proteins for bi-directional movement. However, the composition of the vesicle-motor complex that contains HTT during axonal transport is unknown. Here we analyze the in vivo movement of 16 Rab GTPases within Drosophila larval axons and show that HTT differentially influences the movement of a particular sub-set of these Rab-containing vesicles. While reduction of HTT perturbed the bi-directional motility of Rab3 and Rab19-containing vesicles, only the retrograde motility of Rab7-containing vesicles was disrupted with reduction of HTT. Interestingly, reduction of HTT stimulated the anterograde motility of Rab2-containing vesicles. Simultaneous dual-view imaging revealed that HTT and Rab2, 7 or 19 move together during axonal transport. Collectively, our findings indicate that HTT likely influences the motility of different Rab-containing vesicles and Rab-mediated functions. These findings have important implications for our understanding of the complex role HTT plays within neurons normally, which when disrupted may lead to neuronal death and disease.
Collapse
Affiliation(s)
- Joseph A White
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Eric Anderson
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Katherine Zimmerman
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Kan Hong Zheng
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Roza Rouhani
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Shermali Gunawardena
- Department of Biological Sciences, The State University of New York at Buffalo, Buffalo, NY 14260, USA
| |
Collapse
|
50
|
Abstract
The signaling and transport systems of eucaryotic cells are tightly interconnected: intracellular transport along microtubules and microfilaments is required to position signaling-pathway components, while signaling molecules control activity of motor proteins and their interaction with tracks and cargoes. Recent data, however, give evidence that active transport is engaged in signaling as a means of signal transduction. This review focuses on this specific aspect of the interaction of two systems.
Collapse
Affiliation(s)
- F K Gyoeva
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
| |
Collapse
|