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Riordan R, Saxton A, McMillan PJ, Kow RL, Liachko NF, Kraemer BC. TMEM106B C-terminal fragments aggregate and drive neurodegenerative proteinopathy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.11.598478. [PMID: 38915598 PMCID: PMC11195232 DOI: 10.1101/2024.06.11.598478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Genetic variation in the lysosomal and transmembrane protein 106B (TMEM106B) modifies risk for a diverse range of neurodegenerative disorders, especially frontotemporal lobar degeneration (FTLD) with progranulin (PGRN) haplo-insufficiency, although the molecular mechanisms involved are not yet understood. Through advances in cryo-electron microscopy (cryo-EM), homotypic aggregates of the C-Terminal domain of TMEM106B (TMEM CT) were discovered as a previously unidentified cytosolic proteinopathy in the brains of FTLD, Alzheimer's disease, progressive supranuclear palsy (PSP), and dementia with Lewy bodies (DLB) patients. While it remains unknown what role TMEM CT aggregation plays in neuronal loss, its presence across a range of aging related dementia disorders indicates involvement in multi-proteinopathy driven neurodegeneration. To determine the TMEM CT aggregation propensity and neurodegenerative potential, we characterized a novel transgenic C. elegans model expressing the human TMEM CT fragment constituting the fibrillar core seen in FTLD cases. We found that pan-neuronal expression of human TMEM CT in C. elegans causes neuronal dysfunction as evidenced by behavioral analysis. Cytosolic aggregation of TMEM CT proteins accompanied the behavioral dysfunction driving neurodegeneration, as illustrated by loss of GABAergic neurons. To investigate the molecular mechanisms driving TMEM106B proteinopathy, we explored the impact of PGRN loss on the neurodegenerative effect of TMEM CT expression. To this end, we generated TMEM CT expressing C. elegans with loss of pgrn-1, the C. elegans ortholog of human PGRN. Neither full nor partial loss of pgrn-1 altered the motor phenotype of our TMEM CT model suggesting TMEM CT aggregation occurs downstream of PGRN loss of function. We also tested the ability of genetic suppressors of tauopathy to rescue TMEM CT pathology. We found that genetic knockout of spop-1, sut-2, and sut-6 resulted in weak to no rescue of proteinopathy phenotypes, indicating that the mechanistic drivers of TMEM106B proteinopathy may be distinct from tauopathy. Taken together, our data demonstrate that TMEM CT aggregation can kill neurons. Further, expression of TMEM CT in C. elegans neurons provides a useful model for the functional characterization of TMEM106B proteinopathy in neurodegenerative disease.
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Affiliation(s)
- Ruben Riordan
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA 98104, USA
| | - Aleen Saxton
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA
| | - Pamela J. McMillan
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington 98195, USA
| | - Rebecca L Kow
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA 98104, USA
| | - Nicole F. Liachko
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA 98104, USA
| | - Brian C. Kraemer
- Geriatrics Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA 98104, USA
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington 98195, USA
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington 98195, USA
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2
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Tan LX, Oertel FC, Cheng A, Cobigo Y, Keihani A, Bennett DJ, Abdelhak A, Montes SC, Chapman M, Chen RY, Cordano C, Ward ME, Casaletto K, Kramer JH, Rosen HJ, Boxer A, Miller BL, Green AJ, Elahi FM, Lakkaraju A. Targeting complement C3a receptor resolves mitochondrial hyperfusion and subretinal microglial activation in progranulin-deficient frontotemporal dementia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.595206. [PMID: 38854134 PMCID: PMC11160746 DOI: 10.1101/2024.05.29.595206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Mutations in progranulin ( GRN ) cause frontotemporal dementia ( GRN -FTD) due to deficiency of the pleiotropic protein progranulin. GRN -FTD exhibits diverse pathologies including lysosome dysfunction, lipofuscinosis, microgliosis, and neuroinflammation. Yet, how progranulin loss causes disease remains unresolved. Here, we report that non-invasive retinal imaging of GRN -FTD patients revealed deficits in photoreceptors and the retinal pigment epithelium (RPE) that correlate with cognitive decline. Likewise, Grn -/- mice exhibit early RPE dysfunction, microglial activation, and subsequent photoreceptor loss. Super-resolution live imaging and transcriptomic analyses identified RPE mitochondria as an early driver of retinal dysfunction. Loss of mitochondrial fission protein 1 (MTFP1) in Grn -/- RPE causes mitochondrial hyperfusion and bioenergetic defects, leading to NF-kB-mediated activation of complement C3a-C3a receptor signaling, which drives further mitochondrial hyperfusion and retinal inflammation. C3aR antagonism restores RPE mitochondrial integrity and limits subretinal microglial activation. Our study identifies a previously unrecognized mechanism by which progranulin modulates mitochondrial integrity and complement-mediated neuroinflammation.
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Nelson PT, Fardo DW, Wu X, Aung KZ, Cykowski MD, Katsumata Y. Limbic-predominant age-related TDP-43 encephalopathy (LATE-NC): Co-pathologies and genetic risk factors provide clues about pathogenesis. J Neuropathol Exp Neurol 2024; 83:396-415. [PMID: 38613823 PMCID: PMC11110076 DOI: 10.1093/jnen/nlae032] [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: 04/15/2024] Open
Abstract
Limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC) is detectable at autopsy in more than one-third of people beyond age 85 years and is robustly associated with dementia independent of other pathologies. Although LATE-NC has a large impact on public health, there remain uncertainties about the underlying biologic mechanisms. Here, we review the literature from human studies that may shed light on pathogenetic mechanisms. It is increasingly clear that certain combinations of pathologic changes tend to coexist in aging brains. Although "pure" LATE-NC is not rare, LATE-NC often coexists in the same brains with Alzheimer disease neuropathologic change, brain arteriolosclerosis, hippocampal sclerosis of aging, and/or age-related tau astrogliopathy (ARTAG). The patterns of pathologic comorbidities provide circumstantial evidence of mechanistic interactions ("synergies") between the pathologies, and also suggest common upstream influences. As to primary mediators of vulnerability to neuropathologic changes, genetics may play key roles. Genes associated with LATE-NC include TMEM106B, GRN, APOE, SORL1, ABCC9, and others. Although the anatomic distribution of TDP-43 pathology defines the condition, important cofactors for LATE-NC may include Tau pathology, endolysosomal pathways, and blood-brain barrier dysfunction. A review of the human phenomenology offers insights into disease-driving mechanisms, and may provide clues for diagnostic and therapeutic targets.
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Affiliation(s)
- Peter T Nelson
- Department of Pathology and Laboratory Medicine, University of Kentucky, Lexington, Kentucky, USA
- Department of Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
| | - David W Fardo
- Department of Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
- Department of Biostatistics, University of Kentucky, Lexington, Kentucky, USA
| | - Xian Wu
- Department of Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
- Department of Biostatistics, University of Kentucky, Lexington, Kentucky, USA
| | - Khine Zin Aung
- Department of Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
- Department of Biostatistics, University of Kentucky, Lexington, Kentucky, USA
| | - Matthew D Cykowski
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas, USA
| | - Yuriko Katsumata
- Department of Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
- Department of Biostatistics, University of Kentucky, Lexington, Kentucky, USA
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4
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Zhu M, Zhang G, Meng L, Xiao T, Fang X, Zhang Z. Physiological and pathological functions of TMEM106B in neurodegenerative diseases. Cell Mol Life Sci 2024; 81:209. [PMID: 38710967 DOI: 10.1007/s00018-024-05241-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/13/2024] [Accepted: 04/15/2024] [Indexed: 05/08/2024]
Abstract
As an integral lysosomal transmembrane protein, transmembrane protein 106B (TMEM106B) regulates several aspects of lysosomal function and is associated with neurodegenerative diseases. The TMEM106B gene mutations lead to lysosomal dysfunction and accelerate the pathological progression of Neurodegenerative diseases. Yet, the precise mechanism of TMEM106B in Neurodegenerative diseases remains unclear. Recently, different research teams discovered that TMEM106B is an amyloid protein and the C-terminal domain of TMEM106B forms amyloid fibrils in various Neurodegenerative diseases and normally elderly individuals. In this review, we discussed the physiological functions of TMEM106B. We also included TMEM106B gene mutations that cause neurodegenerative diseases. Finally, we summarized the identification and cryo-electronic microscopic structure of TMEM106B fibrils, and discussed the promising therapeutic strategies aimed at TMEM106B fibrils and the future directions for TMEM106B research in neurodegenerative diseases.
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Affiliation(s)
- Min Zhu
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Guoxin Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Lanxia Meng
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Tingting Xiao
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, 430060, China
| | - Xin Fang
- Department of Neurology, the First Affiliated Hospital of Nanchang University, Nanchang, 330000, China.
| | - Zhentao Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, 430060, China.
- TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, 430000, China.
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Picard C, Miron J, Poirier J. Association of TMEM106B with Cortical APOE Gene Expression in Neurodegenerative Conditions. Genes (Basel) 2024; 15:416. [PMID: 38674351 PMCID: PMC11049136 DOI: 10.3390/genes15040416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 03/21/2024] [Accepted: 03/23/2024] [Indexed: 04/28/2024] Open
Abstract
The e4 allele of the apolipoprotein E gene is the strongest genetic risk factor for sporadic Alzheimer's disease. Nevertheless, how APOE is regulated is still elusive. In a trans-eQTL analysis, we found a genome-wide significant association between transmembrane protein 106B (TMEM106B) genetic variants and cortical APOE mRNA levels in human brains. The goal of this study is to determine whether TMEM106B is mis-regulated in Alzheimer's disease or in other neurodegenerative conditions. Available genomic, transcriptomic and proteomic data from human brains were downloaded from the Mayo Clinic Brain Bank and the Religious Orders Study and Memory and Aging Project. An in-house mouse model of the hippocampal deafferentation/reinnervation was achieved via a stereotaxic lesioning surgery to the entorhinal cortex, and mRNA levels were measured using RNAseq technology. In human temporal cortices, the mean TMEM106B expression was significantly higher in Alzheimer's disease compared to cognitively unimpaired individuals. In the mouse model, hippocampal Tmem106b reached maximum levels during the early phase of reinnervation. These results suggest an active response to tissue damage that is consistent with compensatory synaptic and terminal remodeling.
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Affiliation(s)
- Cynthia Picard
- Douglas Mental Health University Institute, Montreal, QC H4H 1R3, Canada; (C.P.); (J.M.)
- Centre for the Studies on Prevention of Alzheimer’s Disease, Montreal, QC H4H 1R3, Canada
| | - Justin Miron
- Douglas Mental Health University Institute, Montreal, QC H4H 1R3, Canada; (C.P.); (J.M.)
- Centre for the Studies on Prevention of Alzheimer’s Disease, Montreal, QC H4H 1R3, Canada
- Department of Psychiatry, Faculty of Medicine, McGill University, Montreal, QC H3A 0E7, Canada
| | - Judes Poirier
- Douglas Mental Health University Institute, Montreal, QC H4H 1R3, Canada; (C.P.); (J.M.)
- Centre for the Studies on Prevention of Alzheimer’s Disease, Montreal, QC H4H 1R3, Canada
- Department of Psychiatry, Faculty of Medicine, McGill University, Montreal, QC H3A 0E7, Canada
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6
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Edwards GA, Wood CA, He Y, Nguyen Q, Kim PJ, Gomez-Gutierrez R, Park KW, Xu Y, Zurhellen C, Al-Ramahi I, Jankowsky JL. TMEM106B coding variant is protective and deletion detrimental in a mouse model of tauopathy. Acta Neuropathol 2024; 147:61. [PMID: 38526616 DOI: 10.1007/s00401-024-02701-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 01/07/2024] [Accepted: 01/31/2024] [Indexed: 03/27/2024]
Abstract
TMEM106B is a risk modifier of multiple neurological conditions, where a single coding variant and multiple non-coding SNPs influence the balance between susceptibility and resilience. Two key questions that emerge from past work are whether the lone T185S coding variant contributes to protection, and if the presence of TMEM106B is helpful or harmful in the context of disease. Here, we address both questions while expanding the scope of TMEM106B study from TDP-43 to models of tauopathy. We generated knockout mice with constitutive deletion of TMEM106B, alongside knock-in mice encoding the T186S knock-in mutation (equivalent to the human T185S variant), and crossed both with a P301S transgenic tau model to study how these manipulations impacted disease phenotypes. We found that TMEM106B deletion accelerated cognitive decline, hind limb paralysis, tau pathology, and neurodegeneration. TMEM106B deletion also increased transcriptional correlation with human AD and the functional pathways enriched in KO:tau mice aligned with those of AD. In contrast, the coding variant protected against tau-associated cognitive decline, synaptic impairment, neurodegeneration, and paralysis without affecting tau pathology. Our findings reveal that TMEM106B is a critical safeguard against tau aggregation, and that loss of this protein has a profound effect on sequelae of tauopathy. Our study further demonstrates that the coding variant is functionally relevant and contributes to neuroprotection downstream of tau pathology to preserve cognitive function.
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Affiliation(s)
- George A Edwards
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM295, Houston, TX, 77030, USA
| | - Caleb A Wood
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM295, Houston, TX, 77030, USA
| | - Yang He
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, 77030, USA
| | - Quynh Nguyen
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM295, Houston, TX, 77030, USA
| | - Peter J Kim
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM295, Houston, TX, 77030, USA
| | - Ruben Gomez-Gutierrez
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM295, Houston, TX, 77030, USA
| | - Kyung-Won Park
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM295, Houston, TX, 77030, USA
| | - Yong Xu
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Cody Zurhellen
- NeuroScience Associates, 10915 Lake Ridge Drive, Knoxville, TN, 37934, USA
| | - Ismael Al-Ramahi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Joanna L Jankowsky
- Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Mail Stop BCM295, Houston, TX, 77030, USA.
- Department of Neurology, Baylor College of Medicine, Houston, TX, 77030, USA.
- Department of Neurosurgery, Baylor College of Medicine, Houston, TX, 77030, USA.
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.
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7
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Feng T, Du H, Yang C, Wang Y, Hu F. Loss of TMEM106B exacerbates Tau pathology and neurodegeneration in PS19 mice. Acta Neuropathol 2024; 147:62. [PMID: 38526799 DOI: 10.1007/s00401-024-02702-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 03/27/2024]
Abstract
TMEM106B, a gene encoding a lysosome membrane protein, is tightly associated with brain aging, hypomyelinating leukodystrophy, and multiple neurodegenerative diseases, including frontotemporal lobar degeneration with TDP-43 aggregates (FTLD-TDP). Recently, TMEM106B polymorphisms have been associated with tauopathy in chronic traumatic encephalopathy (CTE) and FTLD-TDP patients. However, how TMEM106B influences Tau pathology and its associated neurodegeneration, is unclear. Here we show that loss of TMEM106B enhances the accumulation of pathological Tau, especially in the neuronal soma in the hippocampus, resulting in severe neuronal loss in the PS19 Tau transgenic mice. Moreover, Tmem106b-/- PS19 mice develop significantly increased abnormalities in the neuronal cytoskeleton, autophagy-lysosome activities, as well as glial activation, compared with PS19 and Tmem106b-/- mice. Together, our findings demonstrate that loss of TMEM106B drastically exacerbates Tau pathology and its associated disease phenotypes, and provide new insights into the roles of TMEM106B in neurodegenerative diseases.
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Affiliation(s)
- Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Huan Du
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Cha Yang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Ya Wang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA.
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8
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Takahashi H, Bhagwagar S, Nies SH, Ye H, Han X, Chiasseu MT, Wang G, Mackenzie IR, Strittmatter SM. Reduced progranulin increases tau and α-synuclein inclusions and alters mouse tauopathy phenotypes via glucocerebrosidase. Nat Commun 2024; 15:1434. [PMID: 38365772 PMCID: PMC10873339 DOI: 10.1038/s41467-024-45692-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 02/01/2024] [Indexed: 02/18/2024] Open
Abstract
Comorbid proteinopathies are observed in many neurodegenerative disorders including Alzheimer's disease (AD), increase with age, and influence clinical outcomes, yet the mechanisms remain ill-defined. Here, we show that reduction of progranulin (PGRN), a lysosomal protein associated with TDP-43 proteinopathy, also increases tau inclusions, causes concomitant accumulation of α-synuclein and worsens mortality and disinhibited behaviors in tauopathy mice. The increased inclusions paradoxically protect against spatial memory deficit and hippocampal neurodegeneration. PGRN reduction in male tauopathy attenuates activity of β-glucocerebrosidase (GCase), a protein previously associated with synucleinopathy, while increasing glucosylceramide (GlcCer)-positive tau inclusions. In neuronal culture, GCase inhibition enhances tau aggregation induced by AD-tau. Furthermore, purified GlcCer directly promotes tau aggregation in vitro. Neurofibrillary tangles in human tauopathies are also GlcCer-immunoreactive. Thus, in addition to TDP-43, PGRN regulates tau- and synucleinopathies via GCase and GlcCer. A lysosomal PGRN-GCase pathway may be a common therapeutic target for age-related comorbid proteinopathies.
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Affiliation(s)
- Hideyuki Takahashi
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT, 06536, USA
| | - Sanaea Bhagwagar
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT, 06536, USA
- College of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, USA
| | - Sarah H Nies
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT, 06536, USA
- Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, D-72074, Tübingen, Germany
| | - Hongping Ye
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center At San Antonio, San Antonio, TX, 78229, USA
| | - Xianlin Han
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center At San Antonio, San Antonio, TX, 78229, USA
- Department of Medicine, University of Texas Health Science Center At San Antonio, San Antonio, TX, 78229, USA
| | - Marius T Chiasseu
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT, 06536, USA
| | - Guilin Wang
- Department of Molecular Biophysics and Biochemistry, School of Medicine, Yale University, New Haven, CT, 06520, USA
| | - Ian R Mackenzie
- Department of Pathology, University of British Columbia and Vancouver General Hospital, Vancouver, BC, Canada
| | - Stephen M Strittmatter
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT, 06536, USA.
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Różanowska MB. Lipofuscin, Its Origin, Properties, and Contribution to Retinal Fluorescence as a Potential Biomarker of Oxidative Damage to the Retina. Antioxidants (Basel) 2023; 12:2111. [PMID: 38136230 PMCID: PMC10740933 DOI: 10.3390/antiox12122111] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 12/05/2023] [Accepted: 12/09/2023] [Indexed: 12/24/2023] Open
Abstract
Lipofuscin accumulates with age as intracellular fluorescent granules originating from incomplete lysosomal digestion of phagocytosed and autophagocytosed material. The purpose of this review is to provide an update on the current understanding of the role of oxidative stress and/or lysosomal dysfunction in lipofuscin accumulation and its consequences, particularly for retinal pigment epithelium (RPE). Next, the fluorescence of lipofuscin, spectral changes induced by oxidation, and its contribution to retinal fluorescence are discussed. This is followed by reviewing recent developments in fluorescence imaging of the retina and the current evidence on the prognostic value of retinal fluorescence for the progression of age-related macular degeneration (AMD), the major blinding disease affecting elderly people in developed countries. The evidence of lipofuscin oxidation in vivo and the evidence of increased oxidative damage in AMD retina ex vivo lead to the conclusion that imaging of spectral characteristics of lipofuscin fluorescence may serve as a useful biomarker of oxidative damage, which can be helpful in assessing the efficacy of potential antioxidant therapies in retinal degenerations associated with accumulation of lipofuscin and increased oxidative stress. Finally, amendments to currently used fluorescence imaging instruments are suggested to be more sensitive and specific for imaging spectral characteristics of lipofuscin fluorescence.
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Affiliation(s)
- Małgorzata B. Różanowska
- School of Optometry and Vision Sciences, College of Biomedical and Life Sciences, Cardiff University, Maindy Road, Cardiff CF24 4HQ, Wales, UK;
- Cardiff Institute for Tissue Engineering and Repair (CITER), Redwood Building, King Edward VII Avenue, Cardiff CF10 3NB, Wales, UK
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10
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Todd TW, Shao W, Zhang YJ, Petrucelli L. The endolysosomal pathway and ALS/FTD. Trends Neurosci 2023; 46:1025-1041. [PMID: 37827960 PMCID: PMC10841821 DOI: 10.1016/j.tins.2023.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 08/23/2023] [Accepted: 09/19/2023] [Indexed: 10/14/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are considered to be part of a disease spectrum that is associated with causative mutations and risk variants in a wide range of genes. Mounting evidence indicates that several of these genes are linked to the endolysosomal system, highlighting the importance of this pathway in ALS/FTD. Although many studies have focused on how disruption of this pathway impacts on autophagy, recent findings reveal that this may not be the whole picture: specifically, disrupting autophagy may not be sufficient to induce disease, whereas disrupting the endolysosomal system could represent a crucial pathogenic driver. In this review we discuss the connections between ALS/FTD and the endolysosomal system, including a breakdown of how disease-associated genes are implicated in this pathway. We also explore the potential downstream consequences of disrupting endolysosomal activity in the brain, outside of an effect on autophagy.
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Affiliation(s)
- Tiffany W Todd
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Wei Shao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Yong-Jie Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN, USA.
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11
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Gammaldi N, Pezzini F, Michelucci E, Di Giorgi N, Simonati A, Rocchiccioli S, Santorelli FM, Doccini S. Integrative human and murine multi-omics: Highlighting shared biomarkers in the neuronal ceroid lipofuscinoses. Neurobiol Dis 2023; 189:106349. [PMID: 37952681 DOI: 10.1016/j.nbd.2023.106349] [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: 10/03/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 11/14/2023] Open
Abstract
Neuronal ceroid lipofuscinosis (NCL) is a group of neurodegenerative disorders whose molecular mechanisms remain largely unknown. Omics approaches are among the methods that generate new information on modifying factors and molecular signatures. Moreover, omics data integration can address the need to progressively expand knowledge around the disease and pinpoint specific proteins to promote as candidate biomarkers. In this work, we integrated a total of 62 proteomic and transcriptomic datasets originating from humans and mice, employing a new approach able to define dysregulated processes across species, stages and NCL forms. Moreover, we selected a pool of differentially expressed proteins and genes as species- and form-related biomarkers of disease status/progression and evaluated local and spatial differences in most affected brain regions. Our results offer promising targets for potential new therapeutic strategies and reinforce the hypothesis of a connection between NCLs and other forms of dementia, particularly Alzheimer's disease.
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Affiliation(s)
- N Gammaldi
- Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy; Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Stella Maris Foundation - Pisa, Italy
| | - F Pezzini
- Department of Surgery, Dentistry, Paediatrics and Gynaecology, University of Verona, Verona, Italy
| | - E Michelucci
- Clinical Physiology-National Research Council (IFC-CNR), Pisa, Italy
| | - N Di Giorgi
- Clinical Physiology-National Research Council (IFC-CNR), Pisa, Italy
| | - A Simonati
- Department of Surgery, Dentistry, Paediatrics and Gynaecology, University of Verona, Verona, Italy
| | - S Rocchiccioli
- Clinical Physiology-National Research Council (IFC-CNR), Pisa, Italy
| | - F M Santorelli
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Stella Maris Foundation - Pisa, Italy
| | - S Doccini
- Molecular Medicine for Neurodegenerative and Neuromuscular Diseases Unit, IRCCS Stella Maris Foundation - Pisa, Italy.
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12
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Gillett DA, Wallings RL, Uriarte Huarte O, Tansey MG. Progranulin and GPNMB: interactions in endo-lysosome function and inflammation in neurodegenerative disease. J Neuroinflammation 2023; 20:286. [PMID: 38037070 PMCID: PMC10688479 DOI: 10.1186/s12974-023-02965-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 11/21/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND Alterations in progranulin (PGRN) expression are associated with multiple neurodegenerative diseases (NDs), including frontotemporal dementia (FTD), Alzheimer's disease (AD), Parkinson's disease (PD), and lysosomal storage disorders (LSDs). Recently, the loss of PGRN was shown to result in endo-lysosomal system dysfunction and an age-dependent increase in the expression of another protein associated with NDs, glycoprotein non-metastatic B (GPNMB). MAIN BODY It is unclear what role GPNMB plays in the context of PGRN insufficiency and how they interact and contribute to the development or progression of NDs. This review focuses on the interplay between these two critical proteins within the context of endo-lysosomal health, immune function, and inflammation in their contribution to NDs. SHORT CONCLUSION PGRN and GPNMB are interrelated proteins that regulate disease-relevant processes and may have value as therapeutic targets to delay disease progression or extend therapeutic windows.
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Affiliation(s)
- Drew A Gillett
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA
- Department of Neuroscience, University of Florida, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Rebecca L Wallings
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA
- Department of Neuroscience, University of Florida, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Oihane Uriarte Huarte
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA
- Department of Neuroscience, University of Florida, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Malú Gámez Tansey
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA.
- Department of Neuroscience, University of Florida, Gainesville, FL, USA.
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
- Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, USA.
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13
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Dominguez SL, Laufer BI, Ghosh AS, Li Q, Ruggeri G, Emani MR, Phu L, Friedman BA, Sandoval W, Rose CM, Ngu H, Foreman O, Reichelt M, Juste Y, Lalehzadeh G, Hansen D, Nymark H, Mellal D, Gylling H, Kiełpiński ŁJ, Chih B, Bingol B, Hoogenraad CC, Meilandt WJ, Easton A. TMEM106B reduction does not rescue GRN deficiency in iPSC-derived human microglia and mouse models. iScience 2023; 26:108362. [PMID: 37965143 PMCID: PMC10641752 DOI: 10.1016/j.isci.2023.108362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/28/2023] [Accepted: 10/25/2023] [Indexed: 11/16/2023] Open
Abstract
Heterozygous mutations in the granulin (GRN) gene are a leading cause of frontotemporal lobar degeneration with TDP-43 aggregates (FTLD-TDP). Polymorphisms in TMEM106B have been associated with disease risk in GRN mutation carriers and protective TMEM106B variants associated with reduced levels of TMEM106B, suggesting that lowering TMEM106B might be therapeutic in the context of FTLD. Here, we tested the impact of full deletion and partial reduction of TMEM106B in mouse and iPSC-derived human cell models of GRN deficiency. TMEM106B deletion did not reverse transcriptomic or proteomic profiles in GRN-deficient microglia, with a few exceptions in immune signaling markers. Neither homozygous nor heterozygous Tmem106b deletion normalized disease-associated phenotypes in Grn -/-mice. Furthermore, Tmem106b reduction by antisense oligonucleotide (ASO) was poorly tolerated in Grn -/-mice. These data provide novel insight into TMEM106B and GRN function in microglia cells but do not support lowering TMEM106B levels as a viable therapeutic strategy for treating FTD-GRN.
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Affiliation(s)
- Sara L. Dominguez
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
| | - Benjamin I. Laufer
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
- Department of OMNI Bioinformatics, Genentech, South San Francisco, CA 94080, USA
| | | | - Qingling Li
- Department of Microchemistry, Proteomics, and Lipidomics, Genentech, South San Francisco, CA 94080, USA
| | - Gaia Ruggeri
- Department of Biochemistry and Cellular Pharmacology, Genentech, South San Francisco, CA 94080, USA
| | - Maheswara Reddy Emani
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
- Department of Biochemistry and Cellular Pharmacology, Genentech, South San Francisco, CA 94080, USA
| | - Lilian Phu
- Department of Microchemistry, Proteomics, and Lipidomics, Genentech, South San Francisco, CA 94080, USA
| | - Brad A. Friedman
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
- Department of OMNI Bioinformatics, Genentech, South San Francisco, CA 94080, USA
| | - Wendy Sandoval
- Department of Microchemistry, Proteomics, and Lipidomics, Genentech, South San Francisco, CA 94080, USA
| | - Christopher M. Rose
- Department of Microchemistry, Proteomics, and Lipidomics, Genentech, South San Francisco, CA 94080, USA
| | - Hai Ngu
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | - Oded Foreman
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | - Mike Reichelt
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | - Yves Juste
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
| | - Guita Lalehzadeh
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
| | - Dennis Hansen
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Copenhagen, 2970 Hørsholm, DK, Denmark
| | - Helle Nymark
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Copenhagen, 2970 Hørsholm, DK, Denmark
| | - Denia Mellal
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Copenhagen, 2970 Hørsholm, DK, Denmark
| | - Helene Gylling
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Copenhagen, 2970 Hørsholm, DK, Denmark
| | - Łukasz J. Kiełpiński
- Roche Pharma Research and Early Development, Therapeutic Modalities, Roche Innovation Center Copenhagen, 2970 Hørsholm, DK, Denmark
| | - Ben Chih
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
- Department of Biochemistry and Cellular Pharmacology, Genentech, South San Francisco, CA 94080, USA
| | - Baris Bingol
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
| | | | | | - Amy Easton
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
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14
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Hasan S, Fernandopulle MS, Humble SW, Frankenfield AM, Li H, Prestil R, Johnson KR, Ryan BJ, Wade-Martins R, Ward ME, Hao L. Multi-modal proteomic characterization of lysosomal function and proteostasis in progranulin-deficient neurons. Mol Neurodegener 2023; 18:87. [PMID: 37974165 PMCID: PMC10655356 DOI: 10.1186/s13024-023-00673-w] [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: 09/06/2023] [Accepted: 10/25/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND Progranulin (PGRN) is a lysosomal glycoprotein implicated in various neurodegenerative diseases, including frontotemporal dementia and neuronal ceroid lipofuscinosis. Over 70 mutations discovered in the GRN gene all result in reduced expression of the PGRN protein. Genetic and functional studies point toward a regulatory role for PGRN in lysosome functions. However, the detailed molecular function of PGRN within lysosomes and the impact of PGRN deficiency on lysosomes remain unclear. METHODS We developed multifaceted proteomic techniques to characterize the dynamic lysosomal biology in living human neurons and fixed mouse brain tissues. Using lysosome proximity labeling and immuno-purification of intact lysosomes, we characterized lysosome compositions and interactome in both human induced pluripotent stem cell (iPSC)-derived glutamatergic neurons (i3Neurons) and mouse brains. Using dynamic stable isotope labeling by amino acids in cell culture (dSILAC) proteomics, we measured global protein half-lives in human i3Neurons for the first time. RESULTS Leveraging the multi-modal proteomics and live-cell imaging techniques, we comprehensively characterized how PGRN deficiency changes the molecular and functional landscape of neuronal lysosomes. We found that PGRN loss impairs the lysosome's degradative capacity with increased levels of v-ATPase subunits on the lysosome membrane, increased hydrolases within the lysosome, altered protein regulations related to lysosomal transport, and elevated lysosomal pH. Consistent with impairments in lysosomal function, GRN-null i3Neurons and frontotemporal dementia patient-derived i3Neurons carrying GRN mutation showed pronounced alterations in protein turnover, such as cathepsins and proteins related to supramolecular polymerization and inherited neurodegenerative diseases. CONCLUSION This study suggested PGRN as a critical regulator of lysosomal pH and degradative capacity, which influences global proteostasis in neurons. Beyond the study of progranulin deficiency, these newly developed proteomic methods in neurons and brain tissues provided useful tools and data resources for the field to study the highly dynamic neuronal lysosome biology.
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Affiliation(s)
- Saadia Hasan
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Department of Neurodegenerative Disease, UK Dementia Research Institute, Institute of Neurology, University College London, London, UK
- Augusta University, University of Georgia Medical Partnership, Athens, GA, USA
| | - Michael S Fernandopulle
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
- Medical Scientist Training Program, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Stewart W Humble
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | | | - Haorong Li
- Department of Chemistry, George Washington University, Washington, DC, USA
| | - Ryan Prestil
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Kory R Johnson
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Brent J Ryan
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | - Richard Wade-Martins
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | - Michael E Ward
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA.
| | - Ling Hao
- Department of Chemistry, George Washington University, Washington, DC, USA.
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15
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Feng T, Du H, Hu F. Loss of TMEM106B exacerbates Tau pathology and neurodegeneration in PS19 mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.11.566707. [PMID: 38014238 PMCID: PMC10680640 DOI: 10.1101/2023.11.11.566707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
TMEM106B, a gene encoding a lysosome membrane protein, is tightly associated with brain aging, hypomyelinating leukodystrophy, and multiple neurodegenerative diseases, including frontotemporal lobar degeneration with TDP-43 aggregates (FTLD-TDP). Recently, TMEM106B polymorphisms have been associated with tauopathy in chronic traumatic encephalopathy (CTE) and FTLD-TDP patients. However, how TMEM106B influences Tau pathology and its associated neurodegeneration, is unclear. Here we show that loss of TMEM106B enhances the accumulation of pathological Tau, especially in the neuronal soma in the hippocampus, resulting in severe neuronal loss in the PS19 Tau transgenic mice. Moreover, Tmem106b-/- PS19 mice develop significantly increased disruption of the neuronal cytoskeleton, autophagy-lysosomal function, and lysosomal trafficking along the axon as well as enhanced gliosis compared with PS19 and Tmem106b-/- mice. Together, our findings demonstrate that loss of TMEM106B drastically exacerbates Tau pathology and its associated disease phenotypes, and provide new insights into the roles of TMEM106B in neurodegenerative diseases.
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Affiliation(s)
- Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Huan Du
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
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16
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Boylan MA, Pincetic A, Romano G, Tatton N, Kenkare-Mitra S, Rosenthal A. Targeting Progranulin as an Immuno-Neurology Therapeutic Approach. Int J Mol Sci 2023; 24:15946. [PMID: 37958929 PMCID: PMC10647331 DOI: 10.3390/ijms242115946] [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: 09/19/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023] Open
Abstract
Immuno-neurology is an emerging therapeutic strategy for dementia and neurodegeneration designed to address immune surveillance failure in the brain. Microglia, as central nervous system (CNS)-resident myeloid cells, routinely perform surveillance of the brain and support neuronal function. Loss-of-function (LOF) mutations causing decreased levels of progranulin (PGRN), an immune regulatory protein, lead to dysfunctional microglia and are associated with multiple neurodegenerative diseases, including frontotemporal dementia caused by the progranulin gene (GRN) mutation (FTD-GRN), Alzheimer's disease (AD), Parkinson's disease (PD), limbic-predominant age-related transactivation response deoxyribonucleic acid binding protein 43 (TDP-43) encephalopathy (LATE), and amyotrophic lateral sclerosis (ALS). Immuno-neurology targets immune checkpoint-like proteins, offering the potential to convert aging and dysfunctional microglia into disease-fighting cells that counteract multiple disease pathologies, clear misfolded proteins and debris, promote myelin and synapse repair, optimize neuronal function, support astrocytes and oligodendrocytes, and maintain brain vasculature. Several clinical trials are underway to elevate PGRN levels as one strategy to modulate the function of microglia and counteract neurodegenerative changes associated with various disease states. If successful, these and other immuno-neurology drugs have the potential to revolutionize the treatment of neurodegenerative disorders by harnessing the brain's immune system and shifting it from an inflammatory/pathological state to an enhanced physiological/homeostatic state.
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Affiliation(s)
| | | | | | | | | | - Arnon Rosenthal
- Alector, Inc., 131 Oyster Point Blvd, Suite 600, South San Francisco, CA 94080, USA
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17
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Takahashi H, Perez-Canamas A, Ye H, Han X, Strittmatter SM. Lysosomal TMEM106B interacts with galactosylceramidase to regulate myelin lipid metabolism. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.14.557804. [PMID: 37745346 PMCID: PMC10515910 DOI: 10.1101/2023.09.14.557804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
TMEM106B is an endolysosomal transmembrane protein not only associated with multiple neurological disorders including frontotemporal dementia, Alzheimer's disease, and hypomyelinating leukodystrophy but also potentially involved in COVID-19. Additionally, recent studies have identified amyloid fibrils of C-terminal TMEM106B in both aged healthy and neurodegenerative brains. However, so far little is known about physiological functions of TMEM106B in the endolysosome and how TMEM106B is involved in a wide range of human conditions at molecular levels. Here, we performed lipidomic analysis of the brain of TMEM106B-deficient mice. We found that TMEM106B deficiency significantly decreases levels of two major classes of myelin lipids, galactosylceramide and its sulfated derivative sulfatide. Subsequent co-immunoprecipitation assay showed that TMEM106B physically interacts with galactosylceramidase. We also found that galactosyceramidase activity was significantly increased in TMEM106B-deficient brains. Thus, our results reveal a novel function of TMEM106B interacting with galactosyceramidase to regulate myelin lipid metabolism and have implications for TMEM106B-associated diseases.
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Affiliation(s)
- Hideyuki Takahashi
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT 06536, USA
| | - Azucena Perez-Canamas
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT 06536, USA
| | - Hongping Ye
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center At San Antonio, San Antonio, TX, 78229, USA
| | - Xianlin Han
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center At San Antonio, San Antonio, TX, 78229, USA
- Department of Medicine, University of Texas Health Science Center At San Antonio, San Antonio, TX, 78229, USA
| | - Stephen M. Strittmatter
- Cellular Neuroscience, Neurodegeneration, Repair, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, CT 06536, USA
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18
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Jiao HS, Yuan P, Yu JT. TMEM106B aggregation in neurodegenerative diseases: linking genetics to function. Mol Neurodegener 2023; 18:54. [PMID: 37563705 PMCID: PMC10413548 DOI: 10.1186/s13024-023-00644-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 07/31/2023] [Indexed: 08/12/2023] Open
Abstract
BACKGROUND Mutations of the gene TMEM106B are risk factors for diverse neurodegenerative diseases. Previous understanding of the underlying mechanism focused on the impairment of lysosome biogenesis caused by TMEM106B loss-of-function. However, mutations in TMEM106B increase its expression level, thus the molecular process linking these mutations to the apparent disruption in TMEM106B function remains mysterious. MAIN BODY Recent new studies reported that TMEM106B proteins form intracellular amyloid filaments which universally exist in various neurodegenerative diseases, sometimes being the dominant form of protein aggregation. In light of these new findings, in this review we systematically examined previous efforts in understanding the function of TMEM106B in physiological and pathological conditions. We propose that TMEM106B aggregations could recruit normal TMEM106B proteins and interfere with their function. CONCLUSIONS TMEM106B mutations could lead to lysosome dysfunction by promoting the aggregation of TMEM106B and reducing these aggregations may restore lysosomal function, providing a potential therapeutic target for various neurodegenerative diseases.
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Affiliation(s)
- Hai-Shan Jiao
- Department of Neurology and National Center for Neurological Disorders, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200040, China
| | - Peng Yuan
- Department of Rehabilitation Medicine, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Huashan Hospital, Institute for Translational Brain Research, Fudan University, Shanghai, China.
| | - Jin-Tai Yu
- Department of Neurology and National Center for Neurological Disorders, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200040, China.
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19
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Baggen J, Jacquemyn M, Persoons L, Vanstreels E, Pye VE, Wrobel AG, Calvaresi V, Martin SR, Roustan C, Cronin NB, Reading E, Thibaut HJ, Vercruysse T, Maes P, De Smet F, Yee A, Nivitchanyong T, Roell M, Franco-Hernandez N, Rhinn H, Mamchak AA, Ah Young-Chapon M, Brown E, Cherepanov P, Daelemans D. TMEM106B is a receptor mediating ACE2-independent SARS-CoV-2 cell entry. Cell 2023; 186:3427-3442.e22. [PMID: 37421949 PMCID: PMC10409496 DOI: 10.1016/j.cell.2023.06.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 04/24/2023] [Accepted: 06/08/2023] [Indexed: 07/10/2023]
Abstract
SARS-CoV-2 is associated with broad tissue tropism, a characteristic often determined by the availability of entry receptors on host cells. Here, we show that TMEM106B, a lysosomal transmembrane protein, can serve as an alternative receptor for SARS-CoV-2 entry into angiotensin-converting enzyme 2 (ACE2)-negative cells. Spike substitution E484D increased TMEM106B binding, thereby enhancing TMEM106B-mediated entry. TMEM106B-specific monoclonal antibodies blocked SARS-CoV-2 infection, demonstrating a role of TMEM106B in viral entry. Using X-ray crystallography, cryogenic electron microscopy (cryo-EM), and hydrogen-deuterium exchange mass spectrometry (HDX-MS), we show that the luminal domain (LD) of TMEM106B engages the receptor-binding motif of SARS-CoV-2 spike. Finally, we show that TMEM106B promotes spike-mediated syncytium formation, suggesting a role of TMEM106B in viral fusion. Together, our findings identify an ACE2-independent SARS-CoV-2 infection mechanism that involves cooperative interactions with the receptors heparan sulfate and TMEM106B.
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Affiliation(s)
- Jim Baggen
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Virology and Chemotherapy, Rega Institute, Leuven 3000, Belgium.
| | - Maarten Jacquemyn
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Virology and Chemotherapy, Rega Institute, Leuven 3000, Belgium
| | - Leentje Persoons
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Virology and Chemotherapy, Rega Institute, Leuven 3000, Belgium
| | - Els Vanstreels
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Virology and Chemotherapy, Rega Institute, Leuven 3000, Belgium
| | - Valerie E Pye
- Chromatin Structure and Mobile DNA Laboratory, Francis Crick Institute, London NW1 1AT, UK
| | - Antoni G Wrobel
- Structural Biology of Disease Processes Laboratory, Francis Crick Institute, London NW1 1AT, UK
| | - Valeria Calvaresi
- Department of Chemistry, Britannia House, 7 Trinity Street, King's College London, London SE1 1DB, UK
| | - Stephen R Martin
- Structural Biology of Disease Processes Laboratory, Francis Crick Institute, London NW1 1AT, UK
| | - Chloë Roustan
- Structural Biology Science Technology Platform, Francis Crick Institute, London NW1 1AT, UK
| | - Nora B Cronin
- LonCEM Facility, Francis Crick Institute, London NW1 1AT, UK
| | - Eamonn Reading
- Department of Chemistry, Britannia House, 7 Trinity Street, King's College London, London SE1 1DB, UK
| | - Hendrik Jan Thibaut
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Virology and Chemotherapy, Translational Platform Virology and Chemotherapy, Rega Institute, Leuven 3000, Belgium
| | - Thomas Vercruysse
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Virology and Chemotherapy, Translational Platform Virology and Chemotherapy, Rega Institute, Leuven 3000, Belgium
| | - Piet Maes
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Clinical and Epidemiological Virology, Rega Institute, Leuven 3000, Belgium
| | - Frederik De Smet
- KU Leuven Department of Imaging and Pathology, Laboratory for Precision Cancer Medicine, Translational Cell and Tissue Research Unit, Leuven 3000, Belgium
| | - Angie Yee
- Alector LLC, 131 Oyster Point Blvd. Suite 600, South San Francisco, CA 94080, USA
| | - Toey Nivitchanyong
- Alector LLC, 131 Oyster Point Blvd. Suite 600, South San Francisco, CA 94080, USA
| | - Marina Roell
- Alector LLC, 131 Oyster Point Blvd. Suite 600, South San Francisco, CA 94080, USA
| | | | - Herve Rhinn
- Alector LLC, 131 Oyster Point Blvd. Suite 600, South San Francisco, CA 94080, USA
| | - Alusha Andre Mamchak
- Alector LLC, 131 Oyster Point Blvd. Suite 600, South San Francisco, CA 94080, USA
| | | | - Eric Brown
- Alector LLC, 131 Oyster Point Blvd. Suite 600, South San Francisco, CA 94080, USA
| | - Peter Cherepanov
- Chromatin Structure and Mobile DNA Laboratory, Francis Crick Institute, London NW1 1AT, UK; Department of Infectious Disease, Section of Virology, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
| | - Dirk Daelemans
- KU Leuven Department of Microbiology, Immunology and Transplantation, Laboratory of Virology and Chemotherapy, Rega Institute, Leuven 3000, Belgium.
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20
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Im E, Jiang Y, Stavrides PH, Darji S, Erdjument-Bromage H, Neubert TA, Choi JY, Wegiel J, Lee JH, Nixon RA. Lysosomal dysfunction in Down syndrome and Alzheimer mouse models is caused by v-ATPase inhibition by Tyr 682-phosphorylated APP βCTF. SCIENCE ADVANCES 2023; 9:eadg1925. [PMID: 37494443 PMCID: PMC10371027 DOI: 10.1126/sciadv.adg1925] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 06/23/2023] [Indexed: 07/28/2023]
Abstract
Lysosome dysfunction arises early and propels Alzheimer's disease (AD). Herein, we show that amyloid precursor protein (APP), linked to early-onset AD in Down syndrome (DS), acts directly via its β-C-terminal fragment (βCTF) to disrupt lysosomal vacuolar (H+)-adenosine triphosphatase (v-ATPase) and acidification. In human DS fibroblasts, the phosphorylated 682YENPTY internalization motif of APP-βCTF binds selectively within a pocket of the v-ATPase V0a1 subunit cytoplasmic domain and competitively inhibits association of the V1 subcomplex of v-ATPase, thereby reducing its activity. Lowering APP-βCTF Tyr682 phosphorylation restores v-ATPase and lysosome function in DS fibroblasts and in vivo in brains of DS model mice. Notably, lowering APP-βCTF Tyr682 phosphorylation below normal constitutive levels boosts v-ATPase assembly and activity, suggesting that v-ATPase may also be modulated tonically by phospho-APP-βCTF. Elevated APP-βCTF Tyr682 phosphorylation in two mouse AD models similarly disrupts v-ATPase function. These findings offer previously unknown insight into the pathogenic mechanism underlying faulty lysosomes in all forms of AD.
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Affiliation(s)
- Eunju Im
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ying Jiang
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Philip H. Stavrides
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
| | - Sandipkumar Darji
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
| | - Hediye Erdjument-Bromage
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Thomas A. Neubert
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
- Kimmel Center for Biology and Medicine at the Skirball Institute, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Jun Yong Choi
- Department of Chemistry and Biochemistry, Queens College, Queens, NY 11367, USA
- Ph.D. Programs in Chemistry and Biochemistry, The Graduate Center of the City University of New York, New York, NY 10016, USA
| | - Jerzy Wegiel
- Department of Developmental Neurobiology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY 10314, USA
| | - Ju-Hyun Lee
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ralph A. Nixon
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, USA
- Department of Cell Biology, New York University Grossman School of Medicine, New York, NY 10016, USA
- NYU Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, USA
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21
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Feng T, Minevich G, Liu P, Qin HX, Wozniak G, Pham J, Pham K, Korgaonkar A, Kurnellas M, Defranoux NA, Long H, Mitra A, Hu F. AAV- GRN partially corrects motor deficits and ALS/FTLD-related pathology in Tmem106b-/-Grn-/- mice. iScience 2023; 26:107247. [PMID: 37519899 PMCID: PMC10371829 DOI: 10.1016/j.isci.2023.107247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/18/2023] [Accepted: 06/26/2023] [Indexed: 08/01/2023] Open
Abstract
Loss of function of progranulin (PGRN), encoded by the granulin (GRN) gene, is implicated in several neurodegenerative diseases. Several therapeutics to boost PGRN levels are currently in clinical trials. However, it is difficult to test the efficacy of PGRN-enhancing drugs in mouse models due to the mild phenotypes of Grn-/- mice. Recently, mice deficient in both PGRN and TMEM106B were shown to develop severe motor deficits and pathology. Here, we show that intracerebral ventricle injection of PGRN-expressing AAV1/9 viruses partially rescues motor deficits, neuronal loss, glial activation, and lysosomal abnormalities in Tmem106b-/-Grn-/- mice. Widespread expression of PGRN is detected in both the brain and spinal cord for both AAV subtypes. However, AAV9 but not AAV1-mediated expression of PGRN results in high levels of PGRN in the serum. Together, these data support using the Tmem106b-/-Grn-/- mouse strain as a robust mouse model to determine the efficacy of PGRN-elevating therapeutics.
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Affiliation(s)
- Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | | | - Pengan Liu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Henry Xin Qin
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | | | - Jenny Pham
- Alector Inc, South San Francisco, CA 94080, USA
| | - Khanh Pham
- Alector Inc, South San Francisco, CA 94080, USA
| | | | | | | | - Hua Long
- Alector Inc, South San Francisco, CA 94080, USA
| | | | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
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22
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Cui Z, Wang H, Dong Y, Liu SL, Wang Q. Deciphering and targeting host factors to counteract SARS-CoV-2 and coronavirus infections: insights from CRISPR approaches. Front Genome Ed 2023; 5:1231656. [PMID: 37520399 PMCID: PMC10372414 DOI: 10.3389/fgeed.2023.1231656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 07/04/2023] [Indexed: 08/01/2023] Open
Abstract
Severe respiratory syndrome coronavirus 2 (SARS-CoV-2) and other coronaviruses depend on host factors for the process of viral infection and replication. A better understanding of the dynamic interplay between viral pathogens and host cells, as well as identifying of virus-host dependencies, offers valuable insights into disease mechanisms and informs the development of effective therapeutic strategies against viral infections. This review delves into the key host factors that facilitate or hinder SARS-CoV-2 infection and replication, as identified by CRISPR/Cas9-based screening platforms. Furthermore, we explore CRISPR/Cas13-based gene therapy strategies aimed at targeting these host factors to inhibit viral infection, with the ultimate goal of eradicating SARS-CoV-2 and preventing and treating related coronaviruses for future outbreaks.
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Affiliation(s)
- Zhifen Cui
- Department of Pathology, Duke University School of Medicine, Durham, NC, United States
| | - Hongyan Wang
- Department of Pathology, Duke University School of Medicine, Durham, NC, United States
| | - Yizhou Dong
- Department of Oncological Sciences, Icahn Genomics Institute, Precision Immunology Institute, Tisch Cancer Institute, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Shan-Lu Liu
- Center for Retrovirus Research, Viruses and Emerging Pathogens Program, Department of Veterinary Biosciences, Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - Qianben Wang
- Department of Pathology, Duke University School of Medicine, Durham, NC, United States
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23
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Shafit-Zagardo B, Sidoli S, Goldman JE, DuBois JC, Corboy JR, Strittmatter SM, Guzik H, Edema U, Arackal AG, Botbol YM, Merheb E, Nagra RM, Graff S. TMEM106B Puncta Is Increased in Multiple Sclerosis Plaques, and Reduced Protein in Mice Results in Delayed Lipid Clearance Following CNS Injury. Cells 2023; 12:1734. [PMID: 37443768 PMCID: PMC10340176 DOI: 10.3390/cells12131734] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 06/12/2023] [Accepted: 06/19/2023] [Indexed: 07/15/2023] Open
Abstract
During inflammatory, demyelinating diseases such as multiple sclerosis (MS), inflammation and axonal damage are prevalent early in the course. Axonal damage includes swelling, defects in transport, and failure to clear damaged intracellular proteins, all of which affect recovery and compromise neuronal integrity. The clearance of damaged cell components is important to maintain normal turnover and restore homeostasis. In this study, we used mass spectrometry to identify insoluble proteins within high-speed/mercaptoethanol/sarcosyl-insoluble pellets from purified white matter plaques isolated from the brains of individuals with relapsing-remitting MS (RRMS). We determined that the transmembrane protein 106B (TMEM106B), normally lysosome-associated, is insoluble in RRMS plaques relative to normal-appearing white matter from individuals with Alzheimer's disease and non-neurologic controls. Relative to wild-type mice, hypomorphic mice with a reduction in TMEM106B have increased axonal damage and lipid droplet accumulation in the spinal cord following myelin-oligodendrocyte-glycoprotein-induced experimental autoimmune encephalomyelitis. Additionally, the corpora callosa from cuprizone-challenged hypomorphic mice fail to clear lipid droplets efficiently during remyelination, suggesting that when TMEM106B is compromised, protein and lipid clearance by the lysosome is delayed. As TMEM106B contains putative lipid- and LC3-binding sites, further exploration of these sites is warranted.
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Affiliation(s)
| | - Simone Sidoli
- Department of Biochemistry, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - James E Goldman
- Department of Pathology and Cell Biology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
| | - Juwen C DuBois
- Department of Pathology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - John R Corboy
- Rocky Mountain MS Brain Bank, Department of Neurology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Stephen M Strittmatter
- Departments of Neurology and Neuroscience, Yale School of Medicine, Boyer Center for Molecular Medicine, New Haven, CT 06510, USA
| | - Hillary Guzik
- Analytic Imaging Facility, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Ukuemi Edema
- Department of Anatomic and Clinical Pathology, Montefiore Medical Center, Bronx, NY 10467, USA
| | - Anita G Arackal
- Department of Anatomic and Clinical Pathology, Montefiore Medical Center, Bronx, NY 10467, USA
| | - Yair M Botbol
- Department of Pathology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Emilio Merheb
- Department of Biochemistry, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Rashed M Nagra
- UCLA Brain Bank, VA Healthcare System, Los Angeles, CA 90073, USA
| | - Sarah Graff
- Department of Biochemistry, Albert Einstein College of Medicine, New York, NY 10461, USA
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24
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Zhang T, Pang W, Feng T, Guo J, Wu K, Nunez Santos M, Arthanarisami A, Nana AL, Nguyen Q, Kim PJ, Jankowsky JL, Seeley WW, Hu F. TMEM106B regulates microglial proliferation and survival in response to demyelination. SCIENCE ADVANCES 2023; 9:eadd2676. [PMID: 37146150 PMCID: PMC10162677 DOI: 10.1126/sciadv.add2676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 04/05/2023] [Indexed: 05/07/2023]
Abstract
TMEM106B, a lysosomal transmembrane protein, has been closely associated with brain health. Recently, an intriguing link between TMEM106B and brain inflammation has been discovered, but how TMEM106B regulates inflammation is unknown. Here, we report that TMEM106B deficiency in mice leads to reduced microglia proliferation and activation and increased microglial apoptosis in response to demyelination. We also found an increase in lysosomal pH and a decrease in lysosomal enzyme activities in TMEM106B-deficient microglia. Furthermore, TMEM106B loss results in a significant decrease in the protein levels of TREM2, an innate immune receptor essential for microglia survival and activation. Specific ablation of TMEM106B in microglia results in similar microglial phenotypes and myelination defects in mice, supporting the idea that microglial TMEM106B is critical for proper microglial activities and myelination. Moreover, the TMEM106B risk allele is associated with myelin loss and decreased microglial numbers in humans. Collectively, our study unveils a previously unknown role of TMEM106B in promoting microglial functionality during demyelination.
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Affiliation(s)
- Tingting Zhang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Weilun Pang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Jennifer Guo
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Kenton Wu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Mariela Nunez Santos
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Akshayakeerthi Arthanarisami
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Alissa L. Nana
- Department of Neurology, University of California, San Francisco, CA 94158, USA
| | - Quynh Nguyen
- Department of Neuroscience, Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - Peter J. Kim
- Department of Neuroscience, Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - Joanna L. Jankowsky
- Department of Neuroscience, Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
- Departments of Molecular and Cellular Biology, Neurology, and Neurosurgery, Huffington Center on Aging, Baylor College of Medicine, Houston, TX, USA
| | - William W. Seeley
- Department of Neurology, University of California, San Francisco, CA 94158, USA
- Department of Pathology, University of California, San Francisco, CA 94158, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
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25
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Edwards GA, Wood CA, Nguyen Q, Kim PJ, Gomez-Gutierrez R, Park KW, Zurhellen C, Al-Ramahi I, Jankowsky JL. TMEM106B coding variant is protective and deletion detrimental in a mouse model of tauopathy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.23.533978. [PMID: 36993574 PMCID: PMC10055407 DOI: 10.1101/2023.03.23.533978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
TMEM106B is a risk modifier for a growing list of age-associated dementias including Alzheimer’s and frontotemporal dementia, yet its function remains elusive. Two key questions that emerge from past work are whether the conservative T185S coding variant found in the minor haplotype contributes to protection, and whether the presence of TMEM106B is helpful or harmful in the context of disease. Here we address both issues while extending the testbed for study of TMEM106B from models of TDP to tauopathy. We show that TMEM106B deletion accelerates cognitive decline, hindlimb paralysis, neuropathology, and neurodegeneration. TMEM106B deletion also increases transcriptional overlap with human AD, making it a better model of disease than tau alone. In contrast, the coding variant protects against tau-associated cognitive decline, neurodegeneration, and paralysis without affecting tau pathology. Our findings show that the coding variant contributes to neuroprotection and suggest that TMEM106B is a critical safeguard against tau aggregation.
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26
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Hasan S, Fernandopulle MS, Humble SW, Frankenfield AM, Li H, Prestil R, Johnson KR, Ryan BJ, Wade-Martins R, Ward ME, Hao L. Multi-modal Proteomic Characterization of Lysosomal Function and Proteostasis in Progranulin-Deficient Neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.24.529955. [PMID: 36865171 PMCID: PMC9980118 DOI: 10.1101/2023.02.24.529955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Progranulin (PGRN) is a lysosomal protein implicated in various neurodegenerative diseases. Over 70 mutations discovered in the GRN gene all result in reduced expression of PGRN protein. However, the detailed molecular function of PGRN within lysosomes and the impact of PGRN deficiency on lysosomal biology remain unclear. Here we leveraged multifaceted proteomic techniques to comprehensively characterize how PGRN deficiency changes the molecular and functional landscape of neuronal lysosomes. Using lysosome proximity labeling and immuno-purification of intact lysosomes, we characterized lysosome compositions and interactomes in both human induced pluripotent stem cell (iPSC)-derived glutamatergic neurons (i3Neurons) and mouse brains. Using dynamic stable isotope labeling by amino acids in cell culture (dSILAC) proteomics, we measured global protein half-lives in i3Neurons for the first time and characterized the impact of progranulin deficiency on neuronal proteostasis. Together, this study indicated that PGRN loss impairs the lysosome's degradative capacity with increased levels of v-ATPase subunits on the lysosome membrane, increased catabolic enzymes within the lysosome, elevated lysosomal pH, and pronounced alterations in neuron protein turnover. Collectively, these results suggested PGRN as a critical regulator of lysosomal pH and degradative capacity, which in turn influences global proteostasis in neurons. The multi-modal techniques developed here also provided useful data resources and tools to study the highly dynamic lysosome biology in neurons.
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Affiliation(s)
- Saadia Hasan
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- UK Dementia Research Institute, Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, UK
- MD-PhD program, Augusta University/University of Georgia Medical Partnership, Athens, GA, USA
| | - Michael S. Fernandopulle
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
- Medical Scientist Training Program, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Stewart W. Humble
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Oxford Parkinson’s Disease Centre, Kavli Institute for Nanoscience Discovery, Department of Physiology, Anatomy and Genetics, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | | | - Haorong Li
- Department of Chemistry, George Washington University, Washington, DC, USA
| | - Ryan Prestil
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Kory R. Johnson
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Brent J. Ryan
- Oxford Parkinson’s Disease Centre, Kavli Institute for Nanoscience Discovery, Department of Physiology, Anatomy and Genetics, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - Richard Wade-Martins
- Oxford Parkinson’s Disease Centre, Kavli Institute for Nanoscience Discovery, Department of Physiology, Anatomy and Genetics, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - Michael E. Ward
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Ling Hao
- Department of Chemistry, George Washington University, Washington, DC, USA
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27
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Alotaibi L, Alqasmi A. Identification of a de novo Mutation in TMEM106B in a Saudi Child Causes Hypomyelination Leukodystrophy. Glob Med Genet 2023; 10:38-41. [PMID: 36950148 PMCID: PMC10027483 DOI: 10.1055/s-0043-1764370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2023] Open
Abstract
Hypomyelinating leukodystrophies are one of the white matter disorders caused by a lack of myelin deposition in the central nervous system (CNS). Here, we report the first case of hypomyelinating leukodystrophy in the Middle East and Saudi Arabia. This condition is caused by a mutation in the TMEM106B gene (HLD16; MIM 617964). Hypotonia, congenital nystagmus, delayed motor development, and delayed speech are the main clinical manifestations. The affected patient has mild pyramidal syndrome, a mild intellectual disability, ataxic gait, hyperreflexia, intention tremor, dysmetria, and other motor difficulties. Findings from neuroimaging reveal severe, ongoing, and diffuse hypomyelination identified via the whole exome sequencing, a harmful missense mutation in the TMEM106B gene that is heterozygous. The patient is the offspring of two unrelated persons. The protein's cytoplasmic domain contains a variation that is located in highly conserved residues. In an oligodendroglial cell line, the mutant protein significantly lowered the mRNA production of important myelin genes, decreased branching, and increased cell mortality. TMEM106B is abundantly expressed in neurons and oligodendrocytes in the CNS and is localized in the late endosome and lysosome compartments. TMEM106B levels can be controlled at the transcriptional level through chromatin modification, at the mRNA level through miRNAs, and at the protein level through lysosomal functions. Our findings reveal a novel role of zinc homeostasis in oligodendrocyte development and myelin production and show that variations in TMEM163 induce hypomyelination leukodystrophy.
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Affiliation(s)
- Lena Alotaibi
- Collage of Medicine, King Saud bin Abdul-Aziz University for Health Sciences, Riyadh, Saudi Arabia
- Address for correspondence Leena fahad Alotaibi College of Medicine, King Saud bin Abdulaziz University for Health SciencesRiyadhSaudi Arabia
| | - Amal Alqasmi
- Department of Pediatric Neurology and Epilepsy, King Saud Medical City, Riyadh, Saudi Arabia
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28
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Bauer CS, Webster CP, Shaw AC, Kok JR, Castelli LM, Lin YH, Smith EF, Illanes-Álvarez F, Higginbottom A, Shaw PJ, Azzouz M, Ferraiuolo L, Hautbergue GM, Grierson AJ, De Vos KJ. Loss of TMEM106B exacerbates C9ALS/FTD DPR pathology by disrupting autophagosome maturation. Front Cell Neurosci 2022; 16:1061559. [PMID: 36619668 PMCID: PMC9812496 DOI: 10.3389/fncel.2022.1061559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/22/2022] [Indexed: 12/23/2022] Open
Abstract
Disruption to protein homeostasis caused by lysosomal dysfunction and associated impairment of autophagy is a prominent pathology in amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD). The most common genetic cause of ALS/FTD is a G4C2 hexanucleotide repeat expansion in C9orf72 (C9ALS/FTD). Repeat-associated non-AUG (RAN) translation of G4C2 repeat transcripts gives rise to dipeptide repeat (DPR) proteins that have been shown to be toxic and may contribute to disease etiology. Genetic variants in TMEM106B have been associated with frontotemporal lobar degeneration with TDP-43 pathology and disease progression in C9ALS/FTD. TMEM106B encodes a lysosomal transmembrane protein of unknown function that is involved in various aspects of lysosomal biology. How TMEM106B variants affect C9ALS/FTD is not well understood but has been linked to changes in TMEM106B protein levels. Here, we investigated TMEM106B function in the context of C9ALS/FTD DPR pathology. We report that knockdown of TMEM106B expression exacerbates the accumulation of C9ALS/FTD-associated cytotoxic DPR proteins in cell models expressing RAN-translated or AUG-driven DPRs as well as in C9ALS/FTD-derived iAstrocytes with an endogenous G4C2 expansion by impairing autophagy. Loss of TMEM106B caused a block late in autophagy by disrupting autophagosome to autolysosome maturation which coincided with impaired lysosomal acidification, reduced cathepsin activity, and juxtanuclear clustering of lysosomes. Lysosomal clustering required Rab7A and coincided with reduced Arl8b-mediated anterograde transport of lysosomes to the cell periphery. Increasing Arl8b activity in TMEM106B-deficient cells not only restored the distribution of lysosomes, but also fully rescued autophagy and DPR protein accumulation. Thus, we identified a novel function of TMEM106B in autophagosome maturation via Arl8b. Our findings indicate that TMEM106B variants may modify C9ALS/FTD by regulating autophagic clearance of DPR proteins. Caution should therefore be taken when considering modifying TMEM106B expression levels as a therapeutic approach in ALS/FTD.
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Affiliation(s)
- Claudia S. Bauer
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Christopher P. Webster
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Allan C. Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Jannigje R. Kok
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Lydia M. Castelli
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Ya-Hui Lin
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Emma F. Smith
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Francisco Illanes-Álvarez
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Adrian Higginbottom
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Pamela J. Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Mimoun Azzouz
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Laura Ferraiuolo
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Guillaume M. Hautbergue
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Andrew J. Grierson
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Kurt J. De Vos
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
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29
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Laszlo ZI, Hindley N, Sanchez Avila A, Kline RA, Eaton SL, Lamont DJ, Smith C, Spires-Jones TL, Wishart TM, Henstridge CM. Synaptic proteomics reveal distinct molecular signatures of cognitive change and C9ORF72 repeat expansion in the human ALS cortex. Acta Neuropathol Commun 2022; 10:156. [DOI: 10.1186/s40478-022-01455-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 11/10/2022] Open
Abstract
AbstractIncreasing evidence suggests synaptic dysfunction is a central and possibly triggering factor in Amyotrophic Lateral Sclerosis (ALS). Despite this, we still know very little about the molecular profile of an ALS synapse. To address this gap, we designed a synaptic proteomics experiment to perform an unbiased assessment of the synaptic proteome in the ALS brain. We isolated synaptoneurosomes from fresh-frozen post-mortem human cortex (11 controls and 18 ALS) and stratified the ALS group based on cognitive profile (Edinburgh Cognitive and Behavioural ALS Screen (ECAS score)) and presence of a C9ORF72 hexanucleotide repeat expansion (C9ORF72-RE). This allowed us to assess regional differences and the impact of phenotype and genotype on the synaptic proteome, using Tandem Mass Tagging-based proteomics. We identified over 6000 proteins in our synaptoneurosomes and using robust bioinformatics analysis we validated the strong enrichment of synapses. We found more than 30 ALS-associated proteins in synaptoneurosomes, including TDP-43, FUS, SOD1 and C9ORF72. We identified almost 500 proteins with altered expression levels in ALS, with region-specific changes highlighting proteins and pathways with intriguing links to neurophysiology and pathology. Stratifying the ALS cohort by cognitive status revealed almost 150 specific alterations in cognitively impaired ALS synaptic preparations. Stratifying by C9ORF72-RE status revealed 330 protein alterations in the C9ORF72-RE +ve group, with KEGG pathway analysis highlighting strong enrichment for postsynaptic dysfunction, related to glutamatergic receptor signalling. We have validated some of these changes by western blot and at a single synapse level using array tomography imaging. In summary, we have generated the first unbiased map of the human ALS synaptic proteome, revealing novel insight into this key compartment in ALS pathophysiology and highlighting the influence of cognitive decline and C9ORF72-RE on synaptic composition.
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Neuroimmune dysfunction in frontotemporal dementia: Insights from progranulin and C9orf72 deficiency. Curr Opin Neurobiol 2022; 76:102599. [PMID: 35792478 PMCID: PMC9798541 DOI: 10.1016/j.conb.2022.102599] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/25/2022] [Accepted: 05/31/2022] [Indexed: 12/31/2022]
Abstract
Neuroimmune dysfunction is a cardinal feature of neurodegenerative diseases. But how immune dysregulation in the brain and peripheral organs contribute to neurodegeneration remains unclear. Here, we discuss the recent advances highlighting neuroimmune dysfunction as a key disease-driving factor in frontotemporal dementia (FTD). We provide an overview of the clinical observations supporting a high prevalence of autoimmune diseases in FTD patients with mutations in GRN or C9orf72. We then focus on a myriad of evidence from human genetic studies, mouse models, in vitro assays, and multi-omics platform, which indicate that haploinsufficiency in GRN and C9orf72 promotes neuroimmune dysfunction and contributes to neurodegeneration and premature death. These compelling data provide key insights to disease mechanisms, biomarker discovery, and therapeutic interventions for FTD (120 words).
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Nowacki JC, Fields AM, Fu MM. Emerging cellular themes in leukodystrophies. Front Cell Dev Biol 2022; 10:902261. [PMID: 36003149 PMCID: PMC9393611 DOI: 10.3389/fcell.2022.902261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 06/30/2022] [Indexed: 11/18/2022] Open
Abstract
Leukodystrophies are a broad spectrum of neurological disorders that are characterized primarily by deficiencies in myelin formation. Clinical manifestations of leukodystrophies usually appear during childhood and common symptoms include lack of motor coordination, difficulty with or loss of ambulation, issues with vision and/or hearing, cognitive decline, regression in speech skills, and even seizures. Many cases of leukodystrophy can be attributed to genetic mutations, but they have diverse inheritance patterns (e.g., autosomal recessive, autosomal dominant, or X-linked) and some arise from de novo mutations. In this review, we provide an updated overview of 35 types of leukodystrophies and focus on cellular mechanisms that may underlie these disorders. We find common themes in specialized functions in oligodendrocytes, which are specialized producers of membranes and myelin lipids. These mechanisms include myelin protein defects, lipid processing and peroxisome dysfunction, transcriptional and translational dysregulation, disruptions in cytoskeletal organization, and cell junction defects. In addition, non-cell-autonomous factors in astrocytes and microglia, such as autoimmune reactivity, and intercellular communication, may also play a role in leukodystrophy onset. We hope that highlighting these themes in cellular dysfunction in leukodystrophies may yield conceptual insights on future therapeutic approaches.
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Yang Y, Feng N, Liang L, Jiang R, Pan Y, Geng N, Fan M, Li X, Guo F. Progranulin, a moderator of estrogen/estrogen receptor α binding, regulates bone homeostasis through PERK/p-eIF2 signaling pathway. J Mol Med (Berl) 2022; 100:1191-1207. [PMID: 35838759 DOI: 10.1007/s00109-022-02233-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 06/08/2022] [Accepted: 06/29/2022] [Indexed: 11/28/2022]
Abstract
Under normal conditions, the human body employs the synergistic action of osteoblasts and osteoclasts to maintain a dynamic balance between bone formation and resorption. Bone homeostasis plays a very important role in the process of bone formation. Various bone diseases can occur if bone homeostasis is disrupted. In this study, the serum estrogen levels were significantly increased in the granulin (GRN)-deficient mice and PGRN regulates the binding of estrogen and estrogen receptor α (ERα) and then affects estrogen's ability to regulate bone formation and resorption. In addition, this study also explored the role that PGRN plays in regulating bone homeostasis by affecting the binding of estrogen and estrogen receptors through the protein kinase R-like endoplasmic reticulum kinase/phosphorylation of the eukaryotic initiation factor 2 signaling pathway. In summary, we confirmed the important role of PGRN in regulating the estrogen (E2)/ERα signal in maintaining bone homeostasis. Our findings may provide a new strategy for the treatment of osteoporosis and maintaining bone homeostasis. KEY MESSAGES: PGRN is a molecular regulator of the binding of E2 and ERα signal in maintaining bone homeostasis. PGRN plays in regulating bone homeostasis through the PERK/p-eIF2α signaling pathway. The best therapeutic effect of PGRN in osteoporosis is associated with different concentration of E2.
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Affiliation(s)
- Yuyou Yang
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China
| | - Naibo Feng
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China
| | - Li Liang
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China
| | - Rong Jiang
- Laboratory of Stem Cells and Tissue Engineering, Chongqing Medical University, Chongqing, 400016, China
| | - Yiming Pan
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China
| | - Nana Geng
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China
| | - Mengtian Fan
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China
| | - Xiaoli Li
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China
| | - Fengjin Guo
- Department of Cell Biology and Genetics, Core Facility of Development Biology, Chongqing Medical University, Chongqing, 400016, China.
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Barrantes FJ. The constellation of cholesterol-dependent processes associated with SARS-CoV-2 infection. Prog Lipid Res 2022; 87:101166. [PMID: 35513161 PMCID: PMC9059347 DOI: 10.1016/j.plipres.2022.101166] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 01/11/2023]
Abstract
The role of cholesterol in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other coronavirus-host cell interactions is currently being discussed in the context of two main scenarios: i) the presence of the neutral lipid in cholesterol-rich lipid domains involved in different steps of the viral infection and ii) the alteration of metabolic pathways by the virus over the course of infection. Cholesterol-enriched lipid domains have been reported to occur in the lipid envelope membrane of the virus, in the host-cell plasma membrane, as well as in endosomal and other intracellular membrane cellular compartments. These membrane subdomains, whose chemical and physical properties distinguish them from the bulk lipid bilayer, have been purported to participate in diverse phenomena, from virus-host cell fusion to intracellular trafficking and exit of the virions from the infected cell. SARS-CoV-2 recruits many key proteins that participate under physiological conditions in cholesterol and lipid metabolism in general. This review analyses the status of cholesterol and lipidome proteins in SARS-CoV-2 infection and the new horizons they open for therapeutic intervention.
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Affiliation(s)
- Francisco J. Barrantes
- Corresponding author at: BIOMED UCA-CONICET, Av. Alicia Moreau de Justo 1600, C1107AFF Buenos Aires, Argentina
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34
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Doccini S, Marchese M, Morani F, Gammaldi N, Mero S, Pezzini F, Soliymani R, Santi M, Signore G, Ogi A, Rocchiccioli S, Kanninen KM, Simonati A, Lalowski MM, Santorelli FM. Lysosomal Proteomics Links Disturbances in Lipid Homeostasis and Sphingolipid Metabolism to CLN5 Disease. Cells 2022; 11:1840. [PMID: 35681535 PMCID: PMC9180748 DOI: 10.3390/cells11111840] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/29/2022] [Accepted: 06/01/2022] [Indexed: 12/01/2022] Open
Abstract
CLN5 disease (MIM: 256731) represents a rare late-infantile form of neuronal ceroid lipofuscinosis (NCL), caused by mutations in the CLN5 gene that encodes the CLN5 protein (CLN5p), whose physiological roles stay unanswered. No cure is currently available for CLN5 patients and the opportunities for therapies are lagging. The role of lysosomes in the neuro-pathophysiology of CLN5 disease represents an important topic since lysosomal proteins are directly involved in the primary mechanisms of neuronal injury occurring in various NCL forms. We developed and implemented a lysosome-focused, label-free quantitative proteomics approach, followed by functional validations in both CLN5-knockout neuronal-like cell lines and Cln5-/- mice, to unravel affected pathways and modifying factors involved in this disease scenario. Our results revealed a key role of CLN5p in lipid homeostasis and sphingolipid metabolism and highlighted mutual NCL biomarkers scored with high lysosomal confidence. A newly generated cln5 knockdown zebrafish model recapitulated most of the pathological features seen in NCL disease. To translate the findings from in-vitro and preclinical models to patients, we evaluated whether two FDA-approved drugs promoting autophagy via TFEB activation or inhibition of the glucosylceramide synthase could modulate in-vitro ROS and lipid overproduction, as well as alter the locomotor phenotype in zebrafish. In summary, our data advance the general understanding of disease mechanisms and modifying factors in CLN5 disease, which are recurring in other NCL forms, also stimulating new pharmacological treatments.
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Affiliation(s)
- Stefano Doccini
- Molecular Medicine–IRCCS Stella Maris, 56128 Pisa, Italy; (M.M.); (N.G.); (S.M.); (A.O.)
| | - Maria Marchese
- Molecular Medicine–IRCCS Stella Maris, 56128 Pisa, Italy; (M.M.); (N.G.); (S.M.); (A.O.)
| | - Federica Morani
- Department of Biology, University of Pisa, 56126 Pisa, Italy;
| | - Nicola Gammaldi
- Molecular Medicine–IRCCS Stella Maris, 56128 Pisa, Italy; (M.M.); (N.G.); (S.M.); (A.O.)
- Ph.D. Program in Neuroscience, University of Florence, 50121 Florence, Italy
| | - Serena Mero
- Molecular Medicine–IRCCS Stella Maris, 56128 Pisa, Italy; (M.M.); (N.G.); (S.M.); (A.O.)
| | - Francesco Pezzini
- Department of Surgery, Dentistry, Paediatrics and Gynaecology, University of Verona, 37129 Verona, Italy; (F.P.); (A.S.)
| | - Rabah Soliymani
- HiLIFE, Meilahti Clinical Proteomics Core Facility, Faculty of Medicine, University of Helsinki, 00014 Helsinki, Finland;
| | - Melissa Santi
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, 56127 Pisa, Italy;
| | | | - Asahi Ogi
- Molecular Medicine–IRCCS Stella Maris, 56128 Pisa, Italy; (M.M.); (N.G.); (S.M.); (A.O.)
| | | | - Katja M. Kanninen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, 70210 Kuopio, Finland;
| | - Alessandro Simonati
- Department of Surgery, Dentistry, Paediatrics and Gynaecology, University of Verona, 37129 Verona, Italy; (F.P.); (A.S.)
| | - Maciej M. Lalowski
- HiLIFE, Meilahti Clinical Proteomics Core Facility, Faculty of Medicine, University of Helsinki, 00014 Helsinki, Finland;
- Institute of Bioorganic Chemistry, PAS, Department of Biomedical Proteomics, 61-704 Poznan, Poland
| | - Filippo M. Santorelli
- Molecular Medicine–IRCCS Stella Maris, 56128 Pisa, Italy; (M.M.); (N.G.); (S.M.); (A.O.)
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35
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Takahashi H, Strittmatter SM. An unexpected protein aggregate in diseased and ageing brains. Nature 2022; 605:227-228. [PMID: 35379977 DOI: 10.1038/d41586-022-00873-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Feng T, Luan L, Katz II, Ullah M, Van Deerlin VM, Trojanowski JQ, Lee EB, Hu F. TMEM106B deficiency impairs cerebellar myelination and synaptic integrity with Purkinje cell loss. Acta Neuropathol Commun 2022; 10:33. [PMID: 35287730 PMCID: PMC8919601 DOI: 10.1186/s40478-022-01334-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 02/18/2022] [Indexed: 12/19/2022] Open
Abstract
TMEM106B, a type II lysosomal transmembrane protein, has recently been associated with brain aging, hypomyelinating leukodystrophy, frontotemporal lobar degeneration (FTLD) and several other brain disorders. TMEM106B is critical for proper lysosomal function and TMEM106B deficiency leads to myelination defects, FTLD related pathology, and motor coordination deficits in mice. However, the physiological and pathological functions of TMEM106B in the brain are still not well understood. In this study, we investigate the role of TMEM106B in the cerebellum, dysfunction of which has been associated with FTLD and other brain disorders. We found that TMEM106B is ubiquitously expressed in neurons in the cerebellum, with the highest levels in the Purkinje neurons. Aged TMEM106B-deficient mice show significant loss of Purkinje neurons specifically in the anterior lobe of the cerebellum. Increased microglia and astrocyte activation, as well as an accumulation of ubiquitinated proteins, p62 and TDP-43 were also detected in the cerebellum of aged TMEM106B deficient mice. In the young mice, myelination defects and a significant loss of synapses between Purkinje and deep cerebellar nuclei neurons were observed. Interestingly, TMEM106B deficiency causes distinct lysosomal phenotypes in different types of neurons and glia in the cerebellum and frontal cortex. In humans, TMEM106B rs1990622 risk allele (T/T) is associated with increased Purkinje neuron loss. Taken together, our studies support that TMEM106B regulates lysosomal function in a cell-type-specific manner and TMEM106B is critical for maintaining synaptic integrity and neural functions in the cerebellum.
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Affiliation(s)
- Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Lin Luan
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Isabel Iscol Katz
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Mohammed Ullah
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Vivianna M Van Deerlin
- Department of Pathology and Laboratory Medicine, Center for Neurodegenerative Disease Research, Institute On Aging, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - John Q Trojanowski
- Department of Pathology and Laboratory Medicine, Center for Neurodegenerative Disease Research, Institute On Aging, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Edward B Lee
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA.
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Reifschneider A, Robinson S, van Lengerich B, Gnörich J, Logan T, Heindl S, Vogt MA, Weidinger E, Riedl L, Wind K, Zatcepin A, Pesämaa I, Haberl S, Nuscher B, Kleinberger G, Klimmt J, Götzl JK, Liesz A, Bürger K, Brendel M, Levin J, Diehl‐Schmid J, Suh J, Di Paolo G, Lewcock JW, Monroe KM, Paquet D, Capell A, Haass C. Loss of TREM2 rescues hyperactivation of microglia, but not lysosomal deficits and neurotoxicity in models of progranulin deficiency. EMBO J 2022; 41:e109108. [PMID: 35019161 PMCID: PMC8844989 DOI: 10.15252/embj.2021109108] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 12/13/2021] [Accepted: 12/16/2021] [Indexed: 12/13/2022] Open
Abstract
Haploinsufficiency of the progranulin (PGRN)-encoding gene (GRN) causes frontotemporal lobar degeneration (GRN-FTLD) and results in microglial hyperactivation, TREM2 activation, lysosomal dysfunction, and TDP-43 deposition. To understand the contribution of microglial hyperactivation to pathology, we used genetic and pharmacological approaches to suppress TREM2-dependent transition of microglia from a homeostatic to a disease-associated state. Trem2 deficiency in Grn KO mice reduced microglia hyperactivation. To explore antibody-mediated pharmacological modulation of TREM2-dependent microglial states, we identified antagonistic TREM2 antibodies. Treatment of macrophages from GRN-FTLD patients with these antibodies led to reduced TREM2 signaling due to its enhanced shedding. Furthermore, TREM2 antibody-treated PGRN-deficient microglia derived from human-induced pluripotent stem cells showed reduced microglial hyperactivation, TREM2 signaling, and phagocytic activity, but lysosomal dysfunction was not rescued. Similarly, lysosomal dysfunction, lipid dysregulation, and glucose hypometabolism of Grn KO mice were not rescued by TREM2 ablation. Synaptic loss and neurofilament light-chain (NfL) levels, a biomarker for neurodegeneration, were further elevated in the Grn/Trem2 KO cerebrospinal fluid (CSF). These findings suggest that TREM2-dependent microglia hyperactivation in models of GRN deficiency does not promote neurotoxicity, but rather neuroprotection.
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Affiliation(s)
- Anika Reifschneider
- Division of Metabolic BiochemistryFaculty of MedicineBiomedical Center (BMC)Ludwig‐Maximilians‐Universität MünchenMunichGermany
| | - Sophie Robinson
- Institute for Stroke and Dementia ResearchUniversity Hospital MunichLudwig‐Maximilians‐Universität MünchenMunichGermany
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
| | | | - Johannes Gnörich
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
- Department of Nuclear MedicineUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Todd Logan
- Denali Therapeutics Inc.South San FranciscoCAUSA
| | - Steffanie Heindl
- Institute for Stroke and Dementia ResearchUniversity Hospital MunichLudwig‐Maximilians‐Universität MünchenMunichGermany
| | | | - Endy Weidinger
- Department of NeurologyUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Lina Riedl
- Department of Psychiatry and PsychotherapySchool of MedicineTechnical University of MunichMunichGermany
| | - Karin Wind
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
- Department of Nuclear MedicineUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Artem Zatcepin
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
- Department of Nuclear MedicineUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Ida Pesämaa
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
| | | | - Brigitte Nuscher
- Division of Metabolic BiochemistryFaculty of MedicineBiomedical Center (BMC)Ludwig‐Maximilians‐Universität MünchenMunichGermany
| | | | - Julien Klimmt
- Institute for Stroke and Dementia ResearchUniversity Hospital MunichLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Julia K Götzl
- Division of Metabolic BiochemistryFaculty of MedicineBiomedical Center (BMC)Ludwig‐Maximilians‐Universität MünchenMunichGermany
| | - Arthur Liesz
- Institute for Stroke and Dementia ResearchUniversity Hospital MunichLudwig‐Maximilians‐Universität MünchenMunichGermany
- Munich Cluster for Systems Neurology (SyNergy)MunichGermany
| | - Katharina Bürger
- Institute for Stroke and Dementia ResearchUniversity Hospital MunichLudwig‐Maximilians‐Universität MünchenMunichGermany
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
| | - Matthias Brendel
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
- Department of Nuclear MedicineUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Johannes Levin
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
- Department of Nuclear MedicineUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
- Department of NeurologyUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Janine Diehl‐Schmid
- Department of NeurologyUniversity HospitalLudwig‐Maximilians‐Universität MünchenMunichGermany
- Department of Psychiatry and PsychotherapySchool of MedicineTechnical University of MunichMunichGermany
| | - Jung Suh
- Denali Therapeutics Inc.South San FranciscoCAUSA
| | | | | | | | - Dominik Paquet
- Institute for Stroke and Dementia ResearchUniversity Hospital MunichLudwig‐Maximilians‐Universität MünchenMunichGermany
- Munich Cluster for Systems Neurology (SyNergy)MunichGermany
| | - Anja Capell
- Division of Metabolic BiochemistryFaculty of MedicineBiomedical Center (BMC)Ludwig‐Maximilians‐Universität MünchenMunichGermany
| | - Christian Haass
- Division of Metabolic BiochemistryFaculty of MedicineBiomedical Center (BMC)Ludwig‐Maximilians‐Universität MünchenMunichGermany
- German Center for Neurodegenerative Diseases (DZNE) MunichMunichGermany
- Munich Cluster for Systems Neurology (SyNergy)MunichGermany
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Roney JC, Cheng XT, Sheng ZH. Neuronal endolysosomal transport and lysosomal functionality in maintaining axonostasis. J Cell Biol 2022; 221:213000. [PMID: 35142819 PMCID: PMC8932522 DOI: 10.1083/jcb.202111077] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 02/08/2023] Open
Abstract
Lysosomes serve as degradation hubs for the turnover of endocytic and autophagic cargos, which is essential for neuron function and survival. Deficits in lysosome function result in progressive neurodegeneration in most lysosomal storage disorders and contribute to the pathogenesis of aging-related neurodegenerative diseases. Given their size and highly polarized morphology, neurons face exceptional challenges in maintaining cellular homeostasis in regions far removed from the cell body where mature lysosomes are enriched. Neurons therefore require coordinated bidirectional intracellular transport to sustain efficient clearance capacity in distal axonal regions. Emerging lines of evidence have started to uncover mechanisms and signaling pathways regulating endolysosome transport and maturation to maintain axonal homeostasis, or “axonostasis,” that is relevant to a range of neurologic disorders. In this review, we discuss recent advances in how axonal endolysosomal trafficking, distribution, and lysosomal functionality support neuronal health and become disrupted in several neurodegenerative diseases.
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Affiliation(s)
- Joseph C Roney
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Xiu-Tang Cheng
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Zu-Hang Sheng
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
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Amin S, Carling G, Gan L. New insights and therapeutic opportunities for progranulin-deficient frontotemporal dementia. Curr Opin Neurobiol 2022; 72:131-139. [PMID: 34826653 DOI: 10.1016/j.conb.2021.10.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 10/19/2021] [Indexed: 01/02/2023]
Abstract
Frontotemporal dementia (FTD) is the second most common form of dementia. It affects the frontal and temporal lobes of the brain and has a highly heterogeneous clinical representation with patients presenting with a wide range of behavioral, language, and executive dysfunctions. Etiology of FTD is complex and consists of both familial and sporadic cases. Heterozygous mutations in the GRN gene, resulting in GRN haploinsufficiency, cause progranulin (PGRN)-deficient FTD characterized with cytoplasmic mislocalization of TAR DNA-binding protein 43 kDa (TDP-43) aggregates. GRN codes for PGRN, a secreted protein that is also localized in the endolysosomes and plays a critical role in regulating lysosomal homeostasis. How PGRN deficiency modulates immunity and causes TDP-43 pathology and FTD-related neurodegeneration remains an active area of intense investigation. In the current review, we discuss some of the significant progress made in the past two years that links PGRN deficiency with microglial-associated neuroinflammation, TDP-43 pathology, and lysosomal dysfunction. We also review the opportunities and challenges toward developing therapies and biomarkers to treat PGRN-deficient FTD.
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Affiliation(s)
- Sadaf Amin
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Gillian Carling
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10021, USA; Neuroscience Graduate Program, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Li Gan
- Helen and Robert Appel Alzheimer's Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10021, USA.
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Agrawal I, Tripathi P, Biswas S. Mass Spectrometry Based Protein Biomarkers and Drug Target Discovery and Clinical Diagnosis in Age-Related Progressing Neurodegenerative Diseases. Drug Metab Rev 2022; 54:22-36. [PMID: 35038284 DOI: 10.1080/03602532.2022.2029475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Neurodegenerative diseases correspond to overly complex health disorders that are driven by intersecting pathophysiology that are often trapped in vicious cycles of degeneration and cognitive decline. The usual diagnostic route of these diseases is based on postmortem examination that involves identifying pathology that is specific to the disease in the brain. However, in such cases, accurate diagnosis of the specific disease is limited because clinical disease presentations are often complex that do not easily allow to discriminate patient's cognitive, behavioral, and functional impairment profiles. Additionally, an early identification and therapeutic intervention of these diseases is pivotal to slow the progression of neurodegeneration and extend healthy life span. Mass spectrometry-based techniques have proven to be hugely promising in biological sample analysis and discovery of biomarkers including protein and peptide biomarkers for potential drug target discovery. Recent studies on these biomarkers have demonstrated their potential for applications in early diagnostics and identifying therapeutic targets to battle against neurodegenerative diseases. In this review, we have presented principles of mass spectrometry (MS) and the associated workflows in analyzing and imaging biological samples for discovery of biomarkers. We have especially focused on age- related progressing neurodegenerative diseases such as Alzheimer's (AD) and Parkinson's disease (PD), Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal dementia (FTD) and the related MS-based biomarkers developments for these diseases. Finally, we present a future perspective discussing the potential research directions ahead.
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Affiliation(s)
- Ishita Agrawal
- Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Pallavi Tripathi
- Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, M1 7DN, Manchester, UK
| | - Shyamasri Biswas
- USA Prime Biotech LLC, 1330 NW 6th St., Suite A-2, Gainesville, FL 32601, USA
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Identification of TMEM106B amyloid fibrils provides an updated view of TMEM106B biology in health and disease. Acta Neuropathol 2022; 144:807-819. [PMID: 36056242 PMCID: PMC9547799 DOI: 10.1007/s00401-022-02486-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/15/2022] [Accepted: 08/18/2022] [Indexed: 01/26/2023]
Abstract
Since the initial identification of TMEM106B as a risk factor for frontotemporal lobar degeneration (FTLD), multiple genetic studies have found TMEM106B variants to modulate disease risk in a variety of brain disorders and healthy aging. Neurodegenerative disorders are typically characterized by inclusions of misfolded proteins and since lysosomes are an important site for cellular debris clearance, lysosomal dysfunction has been closely linked to neurodegeneration. Consequently, many causal mutations or genetic risk variants implicated in neurodegenerative diseases encode proteins involved in endosomal-lysosomal function. As an integral lysosomal transmembrane protein, TMEM106B regulates several aspects of lysosomal function and multiple studies have shown that proper TMEM106B protein levels are crucial for maintaining lysosomal health. Yet, the precise function of TMEM106B at the lysosomal membrane is undetermined and it remains unclear how TMEM106B modulates disease risk. Unexpectedly, several independent groups recently showed that the C-terminal domain (AA120-254) of TMEM106B forms amyloid fibrils in the brain of patients with a diverse set of neurodegenerative conditions. The recognition that TMEM106B can form amyloid fibrils and is present across neurodegenerative diseases sheds new light on TMEM106B as a central player in neurodegeneration and brain health, but also raises important new questions. In this review, we summarize current knowledge and place a decade's worth of TMEM106B research into an exciting new perspective.
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42
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Dong T, Tejwani L, Jung Y, Kokubu H, Luttik K, Driessen TM, Lim J. Microglia regulate brain progranulin levels through the endocytosis/lysosomal pathway. JCI Insight 2021; 6:e136147. [PMID: 34618685 PMCID: PMC8663778 DOI: 10.1172/jci.insight.136147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 10/06/2021] [Indexed: 01/01/2023] Open
Abstract
Genetic variants in Granulin (GRN), which encodes the secreted glycoprotein progranulin (PGRN), are associated with several neurodegenerative diseases, including frontotemporal lobar degeneration, neuronal ceroid lipofuscinosis, and Alzheimer's disease. These genetic alterations manifest in pathological changes due to a reduction of PGRN expression; therefore, identifying factors that can modulate PGRN levels in vivo would enhance our understanding of PGRN in neurodegeneration and could reveal novel potential therapeutic targets. Here, we report that modulation of the endocytosis/lysosomal pathway via reduction of Nemo-like kinase (Nlk) in microglia, but not in neurons, can alter total brain Pgrn levels in mice. We demonstrate that Nlk reduction promotes Pgrn degradation by enhancing its trafficking through the endocytosis/lysosomal pathway, specifically in microglia. Furthermore, genetic interaction studies in mice showed that Nlk heterozygosity in Grn haploinsufficient mice further reduces Pgrn levels and induces neuropathological phenotypes associated with PGRN deficiency. Our results reveal a mechanism for Pgrn level regulation in the brain through the active catabolism by microglia and provide insights into the pathophysiology of PGRN-associated diseases.
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Affiliation(s)
- Tingting Dong
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Leon Tejwani
- Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut, USA
- Department of Neuroscience
| | - Youngseob Jung
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Hiroshi Kokubu
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Kimberly Luttik
- Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut, USA
- Department of Neuroscience
| | - Terri M. Driessen
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Janghoo Lim
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
- Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut, USA
- Department of Neuroscience
- Program in Cellular Neuroscience, Neurodegeneration and Repair, and
- Yale Stem Cell Center, Yale School of Medicine, New Haven, Connecticut, USA
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43
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Cellular host factors for SARS-CoV-2 infection. Nat Microbiol 2021; 6:1219-1232. [PMID: 34471255 DOI: 10.1038/s41564-021-00958-0] [Citation(s) in RCA: 106] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 08/03/2021] [Indexed: 02/07/2023]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic has claimed millions of lives and caused a global economic crisis. No effective antiviral drugs are currently available to treat infections of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The medical need imposed by the pandemic has spurred unprecedented research efforts to study coronavirus biology. Every virus depends on cellular host factors and pathways for successful replication. These proviral host factors represent attractive targets for antiviral therapy as they are genetically more stable than viral targets and may be shared among related viruses. The application of various 'omics' technologies has led to the rapid discovery of proviral host factors that are required for the completion of the SARS-CoV-2 life cycle. In this Review, we summarize insights into the proviral host factors that are required for SARS-CoV-2 infection that were mainly obtained using functional genetic and interactome screens. We discuss cellular processes that are important for the SARS-CoV-2 life cycle, as well as parallels with non-coronaviruses. Finally, we highlight host factors that could be targeted by clinically approved molecules and molecules in clinical trials as potential antiviral therapies for COVID-19.
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Lv L, Zhang L. Host proviral and antiviral factors for SARS-CoV-2. Virus Genes 2021; 57:475-488. [PMID: 34510331 PMCID: PMC8435179 DOI: 10.1007/s11262-021-01869-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/28/2021] [Indexed: 12/12/2022]
Abstract
Throughout the viral life cycle, interplays between cellular host factors and virus determine the infectious capacity of the virus. The pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a great threat to human life and health. Extensive studies identified a number of host proviral and antiviral factors for SARS-CoV-2. In this review, we summarize the current understanding of the interplay between SARS-CoV-2 and cellular factors during virus entry and replication. Our review will highlight the future direction of study on the infection and pathogenesis of SARS-CoV-2, as well as novel therapeutic strategies and effective antiviral targets for COVID-19.
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Affiliation(s)
- Lu Lv
- Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, Shandong, China.,Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, Shandong, China
| | - Leiliang Zhang
- Department of Pathogen Biology, School of Basic Medical Sciences, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, Shandong, China. .,Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, Shandong, China.
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45
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Spreading of Alzheimer tau seeds is enhanced by aging and template matching with limited impact of amyloid-β. J Biol Chem 2021; 297:101159. [PMID: 34480901 PMCID: PMC8477193 DOI: 10.1016/j.jbc.2021.101159] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/27/2021] [Accepted: 08/31/2021] [Indexed: 12/13/2022] Open
Abstract
In Alzheimer's disease (AD), deposition of pathological tau and amyloid-β (Aβ) drive synaptic loss and cognitive decline. The injection of misfolded tau aggregates extracted from human AD brains drives templated spreading of tau pathology within WT mouse brain. Here, we assessed the impact of Aβ copathology, of deleting loci known to modify AD risk (Ptk2b, Grn, and Tmem106b) and of pharmacological intervention with an Fyn kinase inhibitor on tau spreading after injection of AD tau extracts. The density and spreading of tau inclusions triggered by human tau seed were unaltered in the hippocampus and cortex of APPswe/PSEN1ΔE9 transgenic and AppNL-F/NL-F knock-in mice. In mice with human tau sequence replacing mouse tau, template matching enhanced neuritic tau burden. Human AD brain tau-enriched preparations contained aggregated Aβ, and the Aβ coinjection caused a redistribution of Aβ aggregates in mutant AD model mice. The injection-induced Aβ phenotype was spatially distinct from tau accumulation and could be ameliorated by depleting Aβ from tau extracts. These data suggest that Aβ and tau pathologies propagate by largely independent mechanisms after their initial formation. Altering the activity of the Fyn and Pyk2 (Ptk2b) kinases involved in Aβ-oligomer–induced signaling, or deleting expression of the progranulin and TMEM106B lysosomal proteins, did not alter the somatic tau inclusion burden or spreading. However, mouse aging had a prominent effect to increase the accumulation of neuritic tau after injection of human AD tau seeds into WT mice. These studies refine our knowledge of factors capable of modulating tau spreading.
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Levine TP. TMEM106B in humans and Vac7 and Tag1 in yeast are predicted to be lipid transfer proteins. Proteins 2021; 90:164-175. [PMID: 34347309 DOI: 10.1002/prot.26201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 07/11/2021] [Accepted: 07/23/2021] [Indexed: 11/05/2022]
Abstract
TMEM106B is an integral membrane protein of late endosomes and lysosomes involved in neuronal function, its overexpression being associated with familial frontotemporal lobar degeneration, and point mutation linked to hypomyelination. It has also been identified in multiple screens for host proteins required for productive SARS-CoV-2 infection. Because standard approaches to understand TMEM106B at the sequence level find no homology to other proteins, it has remained a protein of unknown function. Here, the standard tool PSI-BLAST was used in a nonstandard way to show that the lumenal portion of TMEM106B is a member of the late embryogenesis abundant-2 (LEA-2) domain superfamily. More sensitive tools (HMMER, HHpred, and trRosetta) extended this to predict LEA-2 domains in two yeast proteins. One is Vac7, a regulator of PI(3,5)P2 production in the degradative vacuole, equivalent to the lysosome, which has a LEA-2 domain in its lumenal domain. The other is Tag1, another vacuolar protein, which signals to terminate autophagy and has three LEA-2 domains in its lumenal domain. Further analysis of LEA-2 structures indicated that LEA-2 domains have a long, conserved lipid-binding groove. This implies that TMEM106B, Vac7, and Tag1 may all be lipid transfer proteins in the lumen of late endocytic organelles.
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Natarajan K, Eisfeldt J, Hammond M, Laffita-Mesa JM, Patra K, Khoshnood B, Öijerstedt L, Graff C. Single-cell multimodal analysis in a case with reduced penetrance of Progranulin-Frontotemporal Dementia. Acta Neuropathol Commun 2021; 9:132. [PMID: 34344473 PMCID: PMC8336016 DOI: 10.1186/s40478-021-01234-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 07/23/2021] [Indexed: 11/10/2022] Open
Abstract
We identified an autosomal dominant progranulin mutation carrier without symptoms of dementia in her lifetime (Reduced Penetrance Mutation Carrier, RedPenMC). This resistance to develop expected pathology presents a unique opportunity to interrogate neurodegenerative mechanisms. We performed multimodal single-nuclei analyses of post-mortem frontal cortex from RedPenMC, including transcriptomics and global levels of chromatin marks. RedPenMC had an increased ratio of GRN-expressing microglia, higher levels of activating histone mark H3k4me3 in microglia and lower levels of the repressive chromatin marks H3k9me1 and H3k9me3 in the frontal cortex than her affected mutation carrier son and evidence of higher protein levels of progranulin in both plasma and brain homogenates. Although the study is limited to one case, the results support that restoring brain progranulin levels may be sufficient to escape neurodegeneration and FTD. In addition to previously identified modifier genes, it is possible that epigenetic marks may contribute to the increased progranulin expression in cases of reduced penetrance. These findings may stimulate similar follow-up studies and new therapeutic approaches.
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48
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Terryn J, Verfaillie CM, Van Damme P. Tweaking Progranulin Expression: Therapeutic Avenues and Opportunities. Front Mol Neurosci 2021; 14:713031. [PMID: 34366786 PMCID: PMC8343103 DOI: 10.3389/fnmol.2021.713031] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/07/2021] [Indexed: 01/01/2023] Open
Abstract
Frontotemporal dementia (FTD) is a neurodegenerative disease, leading to behavioral changes and language difficulties. Heterozygous loss-of-function mutations in progranulin (GRN) induce haploinsufficiency of the protein and are associated with up to one-third of all genetic FTD cases worldwide. While the loss of GRN is primarily associated with neurodegeneration, the biological functions of the secreted growth factor-like protein are more diverse, ranging from wound healing, inflammation, vasculogenesis, and metabolic regulation to tumor cell growth and metastasis. To date, no disease-modifying treatments exist for FTD, but different therapeutic approaches to boost GRN levels in the central nervous system are currently being developed (including AAV-mediated GRN gene delivery as well as anti-SORT1 antibody therapy). In this review, we provide an overview of the multifaceted regulation of GRN levels and the corresponding therapeutic avenues. We discuss the opportunities, advantages, and potential drawbacks of the diverse approaches. Additionally, we highlight the therapeutic potential of elevating GRN levels beyond patients with loss-of-function mutations in GRN.
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Affiliation(s)
- Joke Terryn
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Catherine M Verfaillie
- Department of Development and Regeneration, Interdepartmental Stem Cell Institute, KU Leuven-University of Leuven, Leuven, Belgium
| | - Philip Van Damme
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium.,Department of Neurology, University Hospitals Leuven, Leuven, Belgium
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49
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Root J, Merino P, Nuckols A, Johnson M, Kukar T. Lysosome dysfunction as a cause of neurodegenerative diseases: Lessons from frontotemporal dementia and amyotrophic lateral sclerosis. Neurobiol Dis 2021; 154:105360. [PMID: 33812000 PMCID: PMC8113138 DOI: 10.1016/j.nbd.2021.105360] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 03/16/2021] [Accepted: 03/29/2021] [Indexed: 12/11/2022] Open
Abstract
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are fatal neurodegenerative disorders that are thought to exist on a clinical and pathological spectrum. FTD and ALS are linked by shared genetic causes (e.g. C9orf72 hexanucleotide repeat expansions) and neuropathology, such as inclusions of ubiquitinated, misfolded proteins (e.g. TAR DNA-binding protein 43; TDP-43) in the CNS. Furthermore, some genes that cause FTD or ALS when mutated encode proteins that localize to the lysosome or modulate endosome-lysosome function, including lysosomal fusion, cargo trafficking, lysosomal acidification, autophagy, or TFEB activity. In this review, we summarize evidence that lysosomal dysfunction, caused by genetic mutations (e.g. C9orf72, GRN, MAPT, TMEM106B) or toxic-gain of function (e.g. aggregation of TDP-43 or tau), is an important pathogenic disease mechanism in FTD and ALS. Further studies into the normal function of many of these proteins are required and will help uncover the mechanisms that cause lysosomal dysfunction in FTD and ALS. Mutations or polymorphisms in genes that encode proteins important for endosome-lysosome function also occur in other age-dependent neurodegenerative diseases, including Alzheimer's (e.g. APOE, PSEN1, APP) and Parkinson's (e.g. GBA, LRRK2, ATP13A2) disease. A more complete understanding of the common and unique features of lysosome dysfunction across the spectrum of neurodegeneration will help guide the development of therapies for these devastating diseases.
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Affiliation(s)
- Jessica Root
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Paola Merino
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Austin Nuckols
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Michelle Johnson
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Thomas Kukar
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia; Department of Neurology, Emory University, School of Medicine, Atlanta 30322, Georgia.
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50
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Chemical and genetic rescue of in vivo progranulin-deficient lysosomal and autophagic defects. Proc Natl Acad Sci U S A 2021; 118:2022115118. [PMID: 34140407 DOI: 10.1073/pnas.2022115118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In 2006, GRN mutations were first linked to frontotemporal dementia (FTD), the leading cause of non-Alzheimer dementias. While much research has been dedicated to understanding the genetic causes of the disease, our understanding of the mechanistic impacts of GRN deficiency has only recently begun to take shape. With no known cure or treatment available for GRN-related FTD, there is a growing need to rapidly advance genetic and/or small-molecule therapeutics for this disease. This issue is complicated by the fact that, while lysosomal dysfunction seems to be a key driver of pathology, the mechanisms linking a loss of GRN to a pathogenic state remain unclear. In our attempt to address these key issues, we have turned to the nematode, Caenorhabditis elegans, to model, study, and find potential therapies for GRN-deficient FTD. First, we show that the loss of the nematode GRN ortholog, pgrn-1, results in several behavioral and molecular defects, including lysosomal dysfunction and defects in autophagic flux. Our investigations implicate the sphingolipid metabolic pathway in the regulation of many of the in vivo defects associated with pgrn-1 loss. Finally, we utilized these nematodes as an in vivo tool for high-throughput drug screening and identified two small molecules with potential therapeutic applications against GRN/pgrn-1 deficiency. These compounds reverse the biochemical, cellular, and functional phenotypes of GRN deficiency. Together, our results open avenues for mechanistic and therapeutic research into the outcomes of GRN-related neurodegeneration, both genetic and molecular.
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