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Ma R, Chen L, Hu N, Caplan S, Hu G. Cilia and Extracellular Vesicles in Brain Development and Disease. Biol Psychiatry 2024; 95:1020-1029. [PMID: 37956781 PMCID: PMC11087377 DOI: 10.1016/j.biopsych.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 10/21/2023] [Accepted: 11/05/2023] [Indexed: 11/15/2023]
Abstract
Primary and motile cilia are thin, hair-like cellular projections from the cell surface involved in movement, sensing, and communication between cells. Extracellular vesicles (EVs) are small membrane-bound vesicles secreted by cells and contain various proteins, lipids, and nucleic acids that are delivered to and influence the behavior of other cells. Both cilia and EVs are essential for the normal functioning of brain cells, and their malfunction can lead to several neurological diseases. Cilia and EVs can interact with each other in several ways, and this interplay plays a crucial role in facilitating various biological processes, including cell-to-cell communication, tissue homeostasis, and pathogen defense. Cilia and EV crosstalk in the brain is an emerging area of research. Herein, we summarize the detailed molecular mechanisms of cilia and EV interplay and address the ciliary molecules that are involved in signaling and cellular dysfunction in brain development and diseases. Finally, we discuss the potential clinical use of cilia and EVs in brain diseases.
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Affiliation(s)
- Rong Ma
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska; Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Liang Chen
- Department of Computer Science, College of Engineering, Shantou University, Shantou, Guangdong, China
| | - Ningyun Hu
- Millard West High School, Omaha, Nebraska
| | - Steve Caplan
- Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, Nebraska; Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, Nebraska.
| | - Guoku Hu
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska.
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2
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Abstract
Cilia sense and transduce sensory stimuli, homeostatic cues and developmental signals by orchestrating signaling reactions. Extracellular vesicles (EVs) that bud from the ciliary membrane have well-studied roles in the disposal of excess ciliary material, most dramatically exemplified by the shedding of micrometer-sized blocks by photoreceptors. Shedding of EVs by cilia also affords cells with a powerful means to shorten cilia. Finally, cilium-derived EVs may enable cell-cell communication in a variety of organisms, ranging from single-cell parasites and algae to nematodes and vertebrates. Mechanistic understanding of EV shedding by cilia is an active area of study, and future progress may open the door to testing the function of ciliary EV shedding in physiological contexts. In this Cell Science at a Glance and the accompanying poster, we discuss the molecular mechanisms that drive the shedding of ciliary material into the extracellular space, the consequences of shedding for the donor cell and the possible roles that ciliary EVs may have in cell non-autonomous contexts.
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Affiliation(s)
- Irene Ojeda Naharros
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA 94143-3120, USA
| | - Maxence V. Nachury
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA 94143-3120, USA
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Li S, Liang Y, Zou J, Cai Z, Yang H, Yang J, Zhang Y, Lin H, Zhang G, Tan M. SUMOylation of microtubule-cleaving enzyme KATNA1 promotes microtubule severing and neurite outgrowth. J Biol Chem 2022; 298:102292. [PMID: 35868557 PMCID: PMC9403493 DOI: 10.1016/j.jbc.2022.102292] [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: 06/15/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 12/01/2022] Open
Abstract
Katanin p60 ATPase-containing subunit A1 (KATNA1) is a microtubule-cleaving enzyme that regulates the development of neural protrusions through cytoskeletal rearrangements. However, the mechanism underlying the linkage of the small ubiquitin-like modifier (SUMO) protein to KATNA1 and how this modification regulates the development of neural protrusions is unclear. Here we discovered, using mass spectrometry analysis, that SUMO-conjugating enzyme UBC9, an enzyme necessary for the SUMOylation process, was present in the KATNA1 interactome. Moreover, GST-pull down and co-immunoprecipitation assays confirmed that KATNA1 and SUMO interact. We further demonstrated using immunofluorescence experiments that KATNA1 and the SUMO2 isoform colocalized in hippocampal neurites. We also performed a bioinformatics analysis of KATNA1 protein sequences to identify three potentially conserved SUMOylation sites (K77, K157, and K330) among vertebrates. Mutation of K330, but not K77 or K157, abolished KATNA1-induced microtubule severing and decreased the level of binding observed for KATNA1 and SUMO2. Cotransfection of SUMO2 and wildtype KATNA1 in COS7 cells increased microtubule severing, whereas no effect was observed after cotransfection with the K330R KATNA1 mutant. Furthermore, in cultured hippocampal neurons, overexpression of wildtype KATNA1 significantly promoted neurite outgrowth, whereas the K330R mutant eliminated this effect. Taken together, our results demonstrate that the K330 site in KATNA1 is modified by SUMOylation and SUMOylation of KATNA1 promotes microtubule dynamics and hippocampal neurite outgrowth.
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Affiliation(s)
- Shaojin Li
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Yaozhong Liang
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Jianyu Zou
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Zhenbin Cai
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Hua Yang
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Jie Yang
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Yunlong Zhang
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Hongsheng Lin
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
| | - Guowei Zhang
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
| | - Minghui Tan
- Department of Orthopaedics, the First Affiliated Hospital of Jinan University, Guangzhou 510630, China.
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Singh A, Tijore A, Margadant F, Simpson C, Chitkara D, Low BC, Sheetz M. Enhanced tumor cell killing by ultrasound after microtubule depolymerization. Bioeng Transl Med 2021; 6:e10233. [PMID: 34589605 PMCID: PMC8459596 DOI: 10.1002/btm2.10233] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 05/21/2021] [Accepted: 05/23/2021] [Indexed: 11/24/2022] Open
Abstract
Recent studies show that tumor cells are vulnerable to mechanical stresses and undergo calcium-dependent apoptosis (mechanoptosis) with mechanical perturbation by low-frequency ultrasound alone. To determine if tumor cells are particularly sensitive to mechanical stress in certain phases of the cell cycle, inhibitors of the cell-cycle phases are tested for effects on mechanoptosis. Most inhibitors show no significant effect, but inhibitors of mitosis that cause microtubule depolymerization increase the mechanoptosis. Surprisingly, ultrasound treatment also disrupts microtubules independent of inhibitors in tumor cells but not in normal cells. Ultrasound causes calcium entry through mechanosensitive Piezo1 channels that disrupts microtubules via calpain protease activation. Myosin IIA contractility is required for ultrasound-mediated mechanoptosis and microtubule disruption enhances myosin IIA contractility through activation of GEF-H1 and RhoA pathway. Further, ultrasound promotes contractility-dependent Piezo1 expression and localization to the peripheral adhesions where activated Piezo1 allows calcium entry to continue feedback loop. Thus, the synergistic action of ultrasound and nanomolar concentrations of microtubule depolymerizing agents can enhance tumor therapies.
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Affiliation(s)
- Aditi Singh
- Mechanobiology InstituteNational University of SingaporeSingapore
- Department of PharmacyBirla Institute of Technology and SciencePilaniIndia
| | - Ajay Tijore
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Felix Margadant
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Chloe Simpson
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Deepak Chitkara
- Department of PharmacyBirla Institute of Technology and SciencePilaniIndia
| | - Boon Chuan Low
- Mechanobiology InstituteNational University of SingaporeSingapore
| | - Michael Sheetz
- Mechanobiology InstituteNational University of SingaporeSingapore
- Biochemistry and Molecular Biology DepartmentUniversity of Texas Medical BranchGalvestonTexasUSA
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Winnicki K. The Winner Takes It All: Auxin-The Main Player during Plant Embryogenesis. Cells 2020; 9:E606. [PMID: 32138372 PMCID: PMC7140527 DOI: 10.3390/cells9030606] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 02/21/2020] [Accepted: 02/27/2020] [Indexed: 12/11/2022] Open
Abstract
In plants, the first asymmetrical division of a zygote leads to the formation of two cells with different developmental fates. The establishment of various patterns relies on spatial and temporal gene expression, however the precise mechanism responsible for embryonic patterning still needs elucidation. Auxin seems to be the main player which regulates embryo development and controls expression of various genes in a dose-dependent manner. Thus, local auxin maxima and minima which are provided by polar auxin transport underlie cell fate specification. Diverse auxin concentrations in various regions of an embryo would easily explain distinct cell identities, however the question about the mechanism of cellular patterning in cells exposed to similar auxin concentrations still remains open. Thus, specification of cell fate might result not only from the cell position within an embryo but also from events occurring before and during mitosis. This review presents the impact of auxin on the orientation of the cell division plane and discusses the mechanism of auxin-dependent cytoskeleton alignment. Furthermore, close attention is paid to auxin-induced calcium fluxes, which regulate the activity of MAPKs during postembryonic development and which possibly might also underlie cellular patterning during embryogenesis.
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Affiliation(s)
- Konrad Winnicki
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lódź, Poland
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Chua MD, Bogdan AC, Guttman JA. Klebsiella pneumoniae Redistributes Katanin Severing Proteins and Alters Astral Microtubules during Mitosis. Anat Rec (Hoboken) 2019; 303:1859-1864. [PMID: 31595676 DOI: 10.1002/ar.24286] [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: 04/29/2019] [Revised: 07/31/2019] [Accepted: 08/28/2019] [Indexed: 11/09/2022]
Abstract
Klebsiella pneumoniae has become a growing concern within hospitals due to multidrug resistant strains and increasing mortality rates. Recently, we showed that at the subcellular level, K. pneumoniae compromises the integrity of the epithelia by disassembling the microtubule networks of cells through the actions of katanin microtubule severing proteins. In this study, we report on the observation that mitotic cells are targeted by K. pneumoniae and that during infections, the katanin proteins are excluded from the microtubule organizing centers of dividing cells, resulting in the alteration of the microtubule cytoskeleton. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1859-1864, 2020. © 2019 American Association for Anatomy.
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Affiliation(s)
- Michael D Chua
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Alexander C Bogdan
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Julian A Guttman
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
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Mirvis M, Siemers KA, Nelson WJ, Stearns TP. Primary cilium loss in mammalian cells occurs predominantly by whole-cilium shedding. PLoS Biol 2019; 17:e3000381. [PMID: 31314751 PMCID: PMC6699714 DOI: 10.1371/journal.pbio.3000381] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 08/19/2019] [Accepted: 07/02/2019] [Indexed: 12/17/2022] Open
Abstract
The primary cilium is a central signaling hub in cell proliferation and differentiation and is built and disassembled every cell cycle in many animal cells. Disassembly is critically important, as misregulation or delay of cilia loss leads to cell cycle defects. The physical means by which cilia are lost are poorly understood but are thought to involve resorption of ciliary components into the cell body. To investigate cilium loss in mammalian cells, we used live-cell imaging to comprehensively characterize individual events. The predominant mode of cilium loss was rapid deciliation, in which the membrane and axoneme of the cilium was shed from the cell. Gradual resorption was also observed, as well as events in which a period of gradual resorption was followed by rapid deciliation. Deciliation resulted in intact shed cilia that could be recovered from culture medium and contained both membrane and axoneme proteins. We modulated levels of katanin and intracellular calcium, two putative regulators of deciliation, and found that excess katanin promotes cilia loss by deciliation, independently of calcium. Together, these results suggest that mammalian ciliary loss involves a tunable decision between deciliation and resorption.
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Affiliation(s)
- Mary Mirvis
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
| | - Kathleen A. Siemers
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - W. James Nelson
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Tim P. Stearns
- Department of Biology, Stanford University, Stanford, California, United States of America
- Department of Genetics, Stanford University, Stanford, California, United States of America
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Cheung K, Senese S, Kuang J, Bui N, Ongpipattanakul C, Gholkar A, Cohn W, Capri J, Whitelegge JP, Torres JZ. Proteomic Analysis of the Mammalian Katanin Family of Microtubule-severing Enzymes Defines Katanin p80 subunit B-like 1 (KATNBL1) as a Regulator of Mammalian Katanin Microtubule-severing. Mol Cell Proteomics 2016; 15:1658-69. [PMID: 26929214 PMCID: PMC4858946 DOI: 10.1074/mcp.m115.056465] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Indexed: 11/24/2022] Open
Abstract
The Katanin family of microtubule-severing enzymes is critical for remodeling microtubule-based structures that influence cell division, motility, morphogenesis and signaling. Katanin is composed of a catalytic p60 subunit (A subunit, KATNA1) and a regulatory p80 subunit (B subunit, KATNB1). The mammalian genome also encodes two additional A-like subunits (KATNAL1 and KATNAL2) and one additional B-like subunit (KATNBL1) that have remained poorly characterized. To better understand the factors and mechanisms controlling mammalian microtubule-severing, we have taken a mass proteomic approach to define the protein interaction module for each mammalian Katanin subunit and to generate the mammalian Katanin family interaction network (Katan-ome). Further, we have analyzed the function of the KATNBL1 subunit and determined that it associates with KATNA1 and KATNAL1, it localizes to the spindle poles only during mitosis and it regulates Katanin A subunit microtubule-severing activity in vitro. Interestingly, during interphase, KATNBL1 is sequestered in the nucleus through an N-terminal nuclear localization signal. Finally KATNB1 was able to compete the interaction of KATNBL1 with KATNA1 and KATNAL1. These data indicate that KATNBL1 functions as a regulator of Katanin A subunit microtubule-severing activity during mitosis and that it likely coordinates with KATNB1 to perform this function.
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Affiliation(s)
- Keith Cheung
- From the ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095
| | - Silvia Senese
- From the ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095
| | - Jiaen Kuang
- From the ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095
| | - Ngoc Bui
- From the ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095
| | - Chayanid Ongpipattanakul
- From the ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095
| | - Ankur Gholkar
- From the ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095
| | - Whitaker Cohn
- §Pasarow Mass Spectrometry Laboratory, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, California 90095
| | - Joseph Capri
- §Pasarow Mass Spectrometry Laboratory, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, California 90095
| | - Julian P Whitelegge
- §Pasarow Mass Spectrometry Laboratory, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, California 90095; ¶Molecular Biology Institute, University of California, Los Angeles, California, 90095; ‖Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California, 90095
| | - Jorge Z Torres
- From the ‡Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095; ¶Molecular Biology Institute, University of California, Los Angeles, California, 90095; ‖Jonsson Comprehensive Cancer Center, University of California, Los Angeles, California, 90095
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Johjima A, Noi K, Nishikori S, Ogi H, Esaki M, Ogura T. Microtubule severing by katanin p60 AAA+ ATPase requires the C-terminal acidic tails of both α- and β-tubulins and basic amino acid residues in the AAA+ ring pore. J Biol Chem 2015; 290:11762-70. [PMID: 25805498 DOI: 10.1074/jbc.m114.614768] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Indexed: 11/06/2022] Open
Abstract
The microtubule (MT) network is highly dynamic and undergoes dramatic reorganizations during the cell cycle. Dimers of α- and β-tubulins rapidly polymerize to and depolymerize from the end of MT fibrils in an intrinsic GTP-dependent manner. MT severing by ATP-driven enzymes such as katanin and spastin contributes significantly to microtubule dynamics, and it has been shown that katanin p60, a AAA+ family protein, has ATPase and MT-severing activities. The mechanism of MT severing by katanin p60 is poorly understood, and the residues in katanin p60 and tubulins important for severing activity were therefore explored in this study. MT-severing activity, but not ATPase activity, was inhibited by mutations of the conserved aromatic residue and the flanking basic residues in the pore region of the katanin p60 hexameric ring. When the acidic residue-rich C-terminal unstructured segment of either α- or β-tubulin was removed, polymerized MTs were resistant to katanin p60 treatment. Interactions between katanin p60 and the mutant MTs, on the other hand, were unaffected. Taken together, these findings led us to propose that the interactions between the positively charged residues of katanin p60 and the acidic tails of both tubulins are essential for efficient severing of MTs.
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Affiliation(s)
- Ai Johjima
- From the Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811
| | - Kentaro Noi
- From the Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, the Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Tokyo 102-0076, and the Graduate School of Engineering Science, Osaka University, Osaka 560-8531, Japan
| | - Shingo Nishikori
- From the Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811
| | - Hirotsugu Ogi
- the Graduate School of Engineering Science, Osaka University, Osaka 560-8531, Japan
| | - Masatoshi Esaki
- From the Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, the Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Tokyo 102-0076, and
| | - Teru Ogura
- From the Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, the Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Tokyo 102-0076, and
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Zempel H, Luedtke J, Kumar Y, Biernat J, Dawson H, Mandelkow E, Mandelkow EM. Amyloid-β oligomers induce synaptic damage via Tau-dependent microtubule severing by TTLL6 and spastin. EMBO J 2013; 32:2920-37. [PMID: 24065130 PMCID: PMC3831312 DOI: 10.1038/emboj.2013.207] [Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 08/22/2013] [Indexed: 01/23/2023] Open
Abstract
Mislocalization and aggregation of Aβ and Tau combined with loss of synapses and microtubules (MTs) are hallmarks of Alzheimer disease. We exposed mature primary neurons to Aβ oligomers and analysed changes in the Tau/MT system. MT breakdown occurs in dendrites invaded by Tau (Tau missorting) and is mediated by spastin, an MT-severing enzyme. Spastin is recruited by MT polyglutamylation, induced by Tau missorting triggered translocalization of TTLL6 (Tubulin-Tyrosine-Ligase-Like-6) into dendrites. Consequences are spine loss and mitochondria and neurofilament mislocalization. Missorted Tau is not axonally derived, as shown by axonal retention of photoconvertible Dendra2-Tau, but newly synthesized. Recovery from Aβ insult occurs after Aβ oligomers lose their toxicity and requires the kinase MARK (Microtubule-Affinity-Regulating-Kinase). In neurons derived from Tau-knockout mice, MTs and synapses are resistant to Aβ toxicity because TTLL6 mislocalization and MT polyglutamylation are prevented; hence no spastin recruitment and no MT breakdown occur, enabling faster recovery. Reintroduction of Tau re-establishes Aβ-induced toxicity in TauKO neurons, which requires phosphorylation of Tau's KXGS motifs. Transgenic mice overexpressing Tau show TTLL6 translocalization into dendrites and decreased MT stability. The results provide a rationale for MT stabilization as a therapeutic approach.
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Affiliation(s)
- Hans Zempel
- DZNE, German Center for Neurodegenerative Diseases, Bonn, Germany
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Ghosh DK, Dasgupta D, Guha A. Models, Regulations, and Functions of Microtubule Severing by Katanin. ISRN MOLECULAR BIOLOGY 2012; 2012:596289. [PMID: 27335666 PMCID: PMC4890891 DOI: 10.5402/2012/596289] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 08/20/2012] [Indexed: 12/22/2022]
Abstract
Regulation of microtubule dynamics depends on stochastic balance between polymerization and severing process which lead to differential spatiotemporal abundance and distribution of microtubules during cell development, differentiation, and morphogenesis. Microtubule severing by a conserved AAA family protein Katanin has emerged as an important microtubule architecture modulating process in cellular functions like division, migration, shaping and so on. Regulated by several factors, Katanin manifests connective crosstalks in network motifs in regulation of anisotropic severing pattern of microtubule protofilaments in cell type and stage dependent way. Mechanisms of structural disintegration of microtubules by Katanin involve heterogeneous mechanochemical processes and sensitivity of microtubules to Katanin plays significant roles in mitosis/meiosis, neurogenesis, cilia/flagella formation, cell wall development and so on. Deregulated and uncoordinated expression of Katanin has been shown to have implications in pathophysiological conditions. In this paper, we highlight mechanistic models and regulations of microtubule severing by Katanin in context of structure and various functions of Katanin in different organisms.
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Affiliation(s)
- Debasish Kumar Ghosh
- Department of Biological Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur, Nadia 741252, India
| | - Debdeep Dasgupta
- Department of Biological Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur, Nadia 741252, India
| | - Abhishek Guha
- Department of Biological Sciences, Indian Institute of Science Education and Research, Kolkata, Mohanpur, Nadia 741252, India
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