1
|
Bacioglu M, Schweighauser M, Gray D, Lövestam S, Katsinelos T, Quaegebeur A, van Swieten J, Jaunmuktane Z, Davies SW, Scheres SHW, Goedert M, Ghetti B, Spillantini MG. Cleaved TMEM106B forms amyloid aggregates in central and peripheral nervous systems. Acta Neuropathol Commun 2024; 12:99. [PMID: 38886865 PMCID: PMC11181561 DOI: 10.1186/s40478-024-01813-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2024] [Accepted: 06/01/2024] [Indexed: 06/20/2024] Open
Abstract
Filaments made of residues 120-254 of transmembrane protein 106B (TMEM106B) form in an age-dependent manner and can be extracted from the brains of neurologically normal individuals and those of subjects with a variety of neurodegenerative diseases. TMEM106B filament formation requires cleavage at residue 120 of the 274 amino acid protein; at present, it is not known if residues 255-274 form the fuzzy coat of TMEM106B filaments. Here we show that a second cleavage appears likely, based on staining with an antibody raised against residues 263-274 of TMEM106B. We also show that besides the brain TMEM106B inclusions form in dorsal root ganglia and spinal cord, where they were mostly found in non-neuronal cells. We confirm that in the brain, inclusions were most abundant in astrocytes. No inclusions were detected in heart, liver, spleen or hilar lymph nodes. Based on their staining with luminescent conjugated oligothiophenes, we confirm that TMEM106B inclusions are amyloids. By in situ immunoelectron microscopy, TMEM106B assemblies were often found in structures resembling endosomes and lysosomes.
Collapse
Affiliation(s)
- Mehtap Bacioglu
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | | | - Derrick Gray
- IUSM Center for Electron Microscopy (ICEM), Indiana University School of Medicine, Indianapolis, IN, USA
| | - Sofia Lövestam
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Annelies Quaegebeur
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge University Hospitals NHS Foundation Trust and the Cambridge Brain Bank, Cambridge, UK
| | - John van Swieten
- Department of Neurology, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - Zane Jaunmuktane
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Stephen W Davies
- Department of Cell and Developmental Biology, University College, London, UK
| | - Sjors H W Scheres
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Michel Goedert
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Bernardino Ghetti
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | | |
Collapse
|
2
|
Todd TW, Islam NN, Cook CN, Caulfield TR, Petrucelli L. Cryo-EM structures of pathogenic fibrils and their impact on neurodegenerative disease research. Neuron 2024:S0896-6273(24)00359-3. [PMID: 38834068 DOI: 10.1016/j.neuron.2024.05.012] [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: 08/22/2023] [Revised: 03/13/2024] [Accepted: 05/09/2024] [Indexed: 06/06/2024]
Abstract
Neurodegenerative diseases are commonly associated with the formation of aberrant protein aggregates within the brain, and ultrastructural analyses have revealed that the proteins within these inclusions often assemble into amyloid filaments. Cryoelectron microscopy (cryo-EM) has emerged as an effective method for determining the near-atomic structure of these disease-associated filamentous proteins, and the resulting structures have revolutionized the way we think about aberrant protein aggregation and propagation during disease progression. These structures have also revealed that individual fibril conformations may dictate different disease conditions, and this newfound knowledge has improved disease modeling in the lab and advanced the ongoing pursuit of clinical tools capable of distinguishing and targeting different pathogenic entities within living patients. In this review, we summarize some of the recently developed cryo-EM structures of ex vivo α-synuclein, tau, β-amyloid (Aβ), TAR DNA-binding protein 43 (TDP-43), and transmembrane protein 106B (TMEM106B) fibrils and discuss how these structures are being leveraged toward mechanistic research and therapeutic development.
Collapse
Affiliation(s)
- Tiffany W Todd
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Naeyma N Islam
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Casey N Cook
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | | | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
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.
Collapse
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.
| |
Collapse
|
5
|
Vandebergh M, Ramos EM, Corriveau-Lecavalier N, Ramanan VK, Kornak J, Mester C, Kolander T, Brushaber D, Staffaroni AM, Geschwind D, Wolf A, Kantarci K, Gendron TF, Petrucelli L, Van den Broeck M, Wynants S, Baker MC, Borrego – Écija S, Appleby B, Barmada S, Bozoki A, Clark D, Darby RR, Dickerson BC, Domoto-Reilly K, Fields JA, Galasko DR, Ghoshal N, Graff-Radford N, Grant IM, Honig LS, Hsiung GYR, Huey ED, Irwin D, Knopman DS, Kwan JY, Léger GC, Litvan I, Masdeu JC, Mendez MF, Onyike C, Pascual B, Pressman P, Ritter A, Roberson ED, Snyder A, Sullivan AC, Tartaglia MC, Wint D, Heuer HW, Forsberg LK, Boxer AL, Rosen HJ, Boeve BF, Rademakers R. Gene specific effects on brain volume and cognition of TMEM106B in frontotemporal lobar degeneration. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.04.05.24305253. [PMID: 38633784 PMCID: PMC11023674 DOI: 10.1101/2024.04.05.24305253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Background and Objectives TMEM106B has been proposed as a modifier of disease risk in FTLD-TDP, particularly in GRN mutation carriers. Furthermore, TMEM106B has been investigated as a disease modifier in the context of healthy aging and across multiple neurodegenerative diseases. The objective of this study is to evaluate and compare the effect of TMEM106B on gray matter volume and cognition in each of the common genetic FTD groups and in sporadic FTD patients. Methods Participants were enrolled through the ARTFL/LEFFTDS Longitudinal Frontotemporal Lobar Degeneration (ALLFTD) study, which includes symptomatic and presymptomatic individuals with a pathogenic mutation in C9orf72, GRN, MAPT, VCP, TBK1, TARDBP, symptomatic non-mutation carriers, and non-carrier family controls. All participants were genotyped for the TMEM106B rs1990622 SNP. Cross-sectionally, linear mixed-effects models were fitted to assess an association between TMEM106B and genetic group interaction with each outcome measure (gray matter volume and UDS3-EF for cognition), adjusting for education, age, sex and CDR®+NACC-FTLD sum of boxes. Subsequently, associations between TMEM106B and each outcome measure were investigated within the genetic group. For longitudinal modeling, linear mixed-effects models with time by TMEM106B predictor interactions were fitted. Results The minor allele of TMEM106B rs1990622, linked to a decreased risk of FTD, associated with greater gray matter volume in GRN mutation carriers under the recessive dosage model. This was most pronounced in the thalamus in the left hemisphere, with a retained association when considering presymptomatic GRN mutation carriers only. The minor allele of TMEM106B rs1990622 also associated with greater cognitive scores among all C9orf72 mutation carriers and in presymptomatic C9orf72 mutation carriers, under the recessive dosage model. Discussion We identified associations of TMEM106B with gray matter volume and cognition in the presence of GRN and C9orf72 mutations. This further supports TMEM106B as modifier of TDP-43 pathology. The association of TMEM106B with outcomes of interest in presymptomatic GRN and C9orf72 mutation carriers could additionally reflect TMEM106B's impact on divergent pathophysiological changes before the appearance of clinical symptoms.
Collapse
Affiliation(s)
- Marijne Vandebergh
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Eliana Marisa Ramos
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Nick Corriveau-Lecavalier
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN, USA
| | | | - John Kornak
- Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA
| | - Carly Mester
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
| | - Tyler Kolander
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Danielle Brushaber
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA
| | - Adam M Staffaroni
- Department of Neurology, Memory and Aging Center, University of California, San Francisco Weill Institute for Neurosciences, San Francisco, CA, USA
| | - Daniel Geschwind
- Institute for Precision Health, Departments of Neurology, Psychiatry and Human Genetics at David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Amy Wolf
- Department of Neurology, Memory and Aging Center, University of California, San Francisco Weill Institute for Neurosciences, San Francisco, CA, USA
| | - Kejal Kantarci
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Tania F Gendron
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | | | - Marleen Van den Broeck
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Sarah Wynants
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Matthew C Baker
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Sergi Borrego – Écija
- Alzheimer’s Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Fundació Clínic per a la Recerca Biomèdica, Universitat de Barcelona, Barcelona, Spain
| | - Brian Appleby
- Department of Neurology, Case Western Reserve University, Cleveland, OH, USA
| | - Sami Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Andrea Bozoki
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - David Clark
- Department of Neurology, Indiana University, Indianapolis, IN, USA
| | - R Ryan Darby
- Department of Neurology, Vanderbilt University, Nashville, TN, USA
| | | | | | - Julie A. Fields
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN, USA
| | - Douglas R. Galasko
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Nupur Ghoshal
- Departments of Neurology and Psychiatry, Washington University School of Medicine, Washington University, St. Louis, MO, USA
| | | | - Ian M Grant
- Department of Psychiatry and Behavioral Sciences, Northwestern Feinberg School of Medicine, Chicago, IL, USA
| | - Lawrence S Honig
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, NY, USA; Department of Neurology, Columbia University, New York, NY, USA
| | - Ging-Yuek Robin Hsiung
- Division of Neurology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Edward D Huey
- Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - David Irwin
- Department of Neurology and Penn Frontotemporal Degeneration Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - David S Knopman
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN, USA
| | - Justin Y Kwan
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Gabriel C Léger
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Irene Litvan
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Joseph C Masdeu
- Department of Neurology, Houston Methodist, Houston, TX, USA
| | - Mario F Mendez
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Chiadi Onyike
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Belen Pascual
- Department of Neurology, Houston Methodist, Houston, TX, USA
| | - Peter Pressman
- Department of Neurology, University of Colorado, Aurora, CO, USA
| | - Aaron Ritter
- Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV, 89106, USA
| | - Erik D Roberson
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Allison Snyder
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Anna Campbell Sullivan
- Glenn Biggs Institute for Alzheimer’s & Neurodegenerative Diseases, UT Health San Antonio
| | - M Carmela Tartaglia
- Tanz Centre for Research in Neurodegenerative Diseases, Division of Neurology, University of Toronto, Toronto, Ontario, Canada
| | - Dylan Wint
- Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV, 89106, USA
| | - Hilary W Heuer
- Department of Neurology, Memory and Aging Center, University of California, San Francisco Weill Institute for Neurosciences, San Francisco, CA, USA
| | - Leah K Forsberg
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, MN, USA
| | - Adam L Boxer
- Department of Neurology, Memory and Aging Center, University of California, San Francisco Weill Institute for Neurosciences, San Francisco, CA, USA
| | - Howard J Rosen
- Department of Neurology, Memory and Aging Center, University of California, San Francisco Weill Institute for Neurosciences, San Francisco, CA, USA
| | | | - Rosa Rademakers
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| |
Collapse
|
6
|
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.
Collapse
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.
| |
Collapse
|
7
|
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.
Collapse
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.
| |
Collapse
|
8
|
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.
Collapse
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
| |
Collapse
|
9
|
T. Vicente C, Perneel J, Wynants S, Heeman B, Van den Broeck M, Baker M, Cheung S, Faura J, Mackenzie IRA, Rademakers R. C-terminal TMEM106B fragments in human brain correlate with disease-associated TMEM106B haplotypes. Brain 2023; 146:4055-4064. [PMID: 37100087 PMCID: PMC10545506 DOI: 10.1093/brain/awad133] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/03/2023] [Accepted: 04/13/2023] [Indexed: 04/28/2023] Open
Abstract
Transmembrane protein 106B (TMEM106B) is a tightly regulated glycoprotein predominantly localized to endosomes and lysosomes. Genetic studies have implicated TMEM106B haplotypes in the development of multiple neurodegenerative diseases with the strongest effect in frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP), especially in progranulin (GRN) mutation carriers. Recently, cryo-electron microscopy studies showed that a C-terminal fragment (CTF) of TMEM106B (amino acid residues 120-254) forms amyloid fibrils in the brain of patients with FTLD-TDP, but also in brains with other neurodegenerative conditions and normal ageing brain. The functional implication of these fibrils and their relationship to the disease-associated TMEM106B haplotype remain unknown. We performed immunoblotting using a newly developed antibody to detect TMEM106B CTFs in the sarkosyl-insoluble fraction of post-mortem human brain tissue from patients with different proteinopathies (n = 64) as well as neuropathologically normal individuals (n = 10) and correlated the results with age and TMEM106B haplotype. We further compared the immunoblot results with immunohistochemical analyses performed in the same study population. Immunoblot analysis showed the expected ∼30 kDa band in the sarkosyl-insoluble fraction of frontal cortex tissue in at least some individuals with each of the conditions evaluated. Most patients with GRN mutations showed an intense band representing TMEM106B CTF, whereas in most neurologically normal individuals it was absent or much weaker. In the overall cohort, the presence of TMEM106B CTFs correlated strongly with both age (rs = 0.539, P < 0.001) and the presence of the TMEM106B risk haplotype (rs = 0.469, P < 0.001). Although there was a strong overall correlation between the results of immunoblot and immunohistochemistry (rs = 0.662, P < 0.001), 27 cases (37%) were found to have higher amounts of TMEM106B CTFs detected by immunohistochemistry, including most of the older individuals who were neuropathologically normal and individuals who carried two protective TMEM106B haplotypes. Our findings suggest that the formation of sarkosyl-insoluble TMEM106B CTFs is an age-related feature which is modified by TMEM106B haplotype, potentially underlying its disease-modifying effect. The discrepancies between immunoblot and immunohistochemistry in detecting TMEM106B pathology suggests the existence of multiple species of TMEM106B CTFs with possible biological relevance and disease implications.
Collapse
Affiliation(s)
- Cristina T. Vicente
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Jolien Perneel
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Sarah Wynants
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Bavo Heeman
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Marleen Van den Broeck
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Matt Baker
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32233, USA
| | - Simon Cheung
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC V5Z1M9, Canada
| | - Júlia Faura
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Ian R A Mackenzie
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC V5Z1M9, Canada
- Department of Pathology, University of British Columbia, Vancouver, BC V6T 1Z7, Canada
| | - Rosa Rademakers
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32233, USA
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Lacrampe A, Hu F. Unveiling TMEM106B: SARS-CoV-2's secret entrance to the cell. Cell 2023; 186:3329-3331. [PMID: 37541193 DOI: 10.1016/j.cell.2023.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 08/06/2023]
Abstract
The lysosomal membrane protein TMEM106B functions as a proviral factor in SARS-CoV-2 infection, though it was not known how. In this issue of Cell, Baggen et al. demonstrate that TMEM106B serves as an ACE2-independent receptor for SARS-CoV-2 entry by promoting the fusion of the viral membrane with the lysosomal membrane.
Collapse
Affiliation(s)
- Alexander Lacrampe
- 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.
| |
Collapse
|
12
|
Neumann M, Perneel J, Cheung S, Van den Broeck M, Nygaard H, Hsiung GYR, Wynants S, Heeman B, Rademakers R, Mackenzie IRA. Limbic-predominant age-related TDP-43 proteinopathy (LATE-NC) is associated with abundant TMEM106B pathology. Acta Neuropathol 2023:10.1007/s00401-023-02580-2. [PMID: 37171635 DOI: 10.1007/s00401-023-02580-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/25/2023] [Accepted: 04/25/2023] [Indexed: 05/13/2023]
Affiliation(s)
- Manuela Neumann
- Department of Neuropathology, University of Tübingen, Tübingen, Germany
- Molecular Neuropathology of Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Tübingen, Germany
| | - Jolien Perneel
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Simon Cheung
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC, Canada
| | - Marleen Van den Broeck
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Haakon Nygaard
- Division of Neurology, University of British Columbia, Vancouver, BC, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Ging-Yuek R Hsiung
- Division of Neurology, University of British Columbia, Vancouver, BC, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Sarah Wynants
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Bavo Heeman
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Rosa Rademakers
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Ian R A Mackenzie
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC, Canada.
- Division of Neurology, University of British Columbia, Vancouver, BC, Canada.
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada.
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
13
|
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.
Collapse
|
14
|
Perneel J, Neumann M, Heeman B, Cheung S, Van den Broeck M, Wynants S, Baker M, Vicente CT, Faura J, Rademakers R, Mackenzie IRA. Accumulation of TMEM106B C-terminal fragments in neurodegenerative disease and aging. Acta Neuropathol 2023; 145:285-302. [PMID: 36527486 DOI: 10.1007/s00401-022-02531-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/21/2022] [Accepted: 12/09/2022] [Indexed: 12/23/2022]
Abstract
Several studies using cryogenic electron microscopy (cryo-EM) techniques recently reported the isolation and characterization of novel protein filaments, composed of a C-terminal fragment (CTF) of the endolysosomal transmembrane protein 106B (TMEM106B), from human post-mortem brain tissue with various neurodegenerative conditions and normal aging. Genetic variation in TMEM106B is known to influence the risk and presentation of several neurodegenerative diseases, especially frontotemporal dementia (FTD) caused by mutations in the progranulin gene (GRN). To further elucidate the significance of TMEM106B CTF, we performed immunohistochemistry with antibodies directed against epitopes within the filament-forming C-terminal region of TMEM106B. Accumulation of TMEM106B C-terminal immunoreactive (TMEM-ir) material was a common finding in all the conditions evaluated, including frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP), Alzheimer's disease, tauopathies, synucleinopathies and neurologically normal aging. TMEM-ir material was present in a wide range of brain cell types and in a broad neuroanatomical distribution; however, there was no co-localization of TMEM-ir material with other neurodegenerative proteins in cellular inclusions. In most conditions, the presence and abundance of TMEM-ir aggregates correlated strongly with patient age and showed only a weak correlation with the TMEM106B haplotype or the primary pathological diagnosis. However, all patients with FTD caused by GRN mutations were found to have high levels of TMEM-ir material, including several who were relatively young (< 60 years). These findings suggest that the accumulation of TMEM106B CTF is a common age-related phenomenon, which may reflect lysosomal dysfunction. Although its significance in most neurodegenerative conditions remains uncertain, the consistent finding of extensive TMEM-ir material in cases of FTLD-TDP with GRN mutations further supports a pathomechanistic role of TMEM106B and lysosomal dysfunction in this specific disease population.
Collapse
Affiliation(s)
- Jolien Perneel
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Manuela Neumann
- Department of Neuropathology, University of Tübingen, Tübingen, Germany.,Molecular Neuropathology of Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Tübingen, Germany
| | - Bavo Heeman
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Simon Cheung
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC, Canada
| | - Marleen Van den Broeck
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Sarah Wynants
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Matt Baker
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Cristina T Vicente
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Júlia Faura
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Rosa Rademakers
- VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.,Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Ian R A Mackenzie
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC, Canada. .,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
15
|
Hoq MR, Bharath SR, Hallinan GI, Fernandez A, Vago FS, Ozcan KA, Li D, Garringer HJ, Vidal R, Ghetti B, Jiang W. Cross-β helical filaments of Tau and TMEM106B in Gray and White Matter of Multiple System Tauopathy with presenile Dementia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.09.523314. [PMID: 36711790 PMCID: PMC9882095 DOI: 10.1101/2023.01.09.523314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Background The Microtubule-Associated Protein Tau (MAPT) is one of the proteins that are central to neurodegenerative diseases. The nature of intracellular tau aggregates is determined by the cell types whether neuronal or glial, the participating tau isoforms, and the structure of the amyloid filament. The transmembrane protein 106B (TMEM106B) has recently emerged as another significant player in neurodegeneration and aging. In the central nervous system, the composition of the gray and white matter differs considerably. The gray matter consists of nerve cell bodies, dendrites, unmyelinated axons, synaptic terminals, astrocytes, oligodendrocytes (satellite cells) and microglia. The white matter differs from the gray for the presence of axonal tracts as the only neuronal component and for the absence of nerve cell bodies, dendrites and synaptic terminals. Cryogenic electron microscopy (cryo-EM) studies have unveiled the structure of tau and TMEM106B, from the cerebral cortex, in several neurodegenerative diseases; however, whether tau and TMEM106B filaments from the gray and white matter share a common fold requires additional investigation. Methods We isolated tau and TMEM106B from the cerebral cortex and white matter of the frontal lobes of two individuals affected by multiple system tauopathy with presenile dementia (MSTD), a disease caused by the MAPT intron 10 mutation +3. We used immunostaining, biochemical, genetics and cryo-EM methods to characterize tau and TMEM106B. Results We determined that tau filaments in the gray and the white matter of MSTD individuals can induce tau aggregation and have identical AGD type 2 folds. TMEM106B amyloid filaments were also found in the gray and white matter of MSTD; the filament folds were identical in the two anatomical regions. Conclusions Our findings show for the first time that in MSTD two types of amyloid filaments extracted from the gray matter have identical folds to those extracted from the white matter. Whether in this genetic disorder there is a relationship in the pathogenesis of the tau and TMEM106B filaments, remains to be determined. Furthermore, additional studies are needed for other proteins and other neurodegenerative diseases to establish whether filaments extracted from the gray and white matter would have identical folds.
Collapse
|