1
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Keeley O, Coyne AN. Nuclear and degradative functions of the ESCRT-III pathway: implications for neurodegenerative disease. Nucleus 2024; 15:2349085. [PMID: 38700207 PMCID: PMC11073439 DOI: 10.1080/19491034.2024.2349085] [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: 02/11/2024] [Accepted: 04/24/2024] [Indexed: 05/05/2024] Open
Abstract
The ESCRT machinery plays a pivotal role in membrane-remodeling events across multiple cellular processes including nuclear envelope repair and reformation, nuclear pore complex surveillance, endolysosomal trafficking, and neuronal pruning. Alterations in ESCRT-III functionality have been associated with neurodegenerative diseases including Frontotemporal Dementia (FTD), Amyotrophic Lateral Sclerosis (ALS), and Alzheimer's Disease (AD). In addition, mutations in specific ESCRT-III proteins have been identified in FTD/ALS. Thus, understanding how disruptions in the fundamental functions of this pathway and its individual protein components in the human central nervous system (CNS) may offer valuable insights into mechanisms underlying neurodegenerative disease pathogenesis and identification of potential therapeutic targets. In this review, we discuss ESCRT components, dynamics, and functions, with a focus on the ESCRT-III pathway. In addition, we explore the implications of altered ESCRT-III function for neurodegeneration with a primary emphasis on nuclear surveillance and endolysosomal trafficking within the CNS.
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Affiliation(s)
- Olivia Keeley
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Alyssa N. Coyne
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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2
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Fare CM, Rothstein JD. Nuclear pore dysfunction and disease: a complex opportunity. Nucleus 2024; 15:2314297. [PMID: 38383349 PMCID: PMC10883112 DOI: 10.1080/19491034.2024.2314297] [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: 11/27/2023] [Accepted: 01/30/2024] [Indexed: 02/23/2024] Open
Abstract
The separation of genetic material from bulk cytoplasm has enabled the evolution of increasingly complex organisms, allowing for the development of sophisticated forms of life. However, this complexity has created new categories of dysfunction, including those related to the movement of material between cellular compartments. In eukaryotic cells, nucleocytoplasmic trafficking is a fundamental biological process, and cumulative disruptions to nuclear integrity and nucleocytoplasmic transport are detrimental to cell survival. This is particularly true in post-mitotic neurons, where nuclear pore injury and errors to nucleocytoplasmic trafficking are strongly associated with neurodegenerative disease. In this review, we summarize the current understanding of nuclear pore biology in physiological and pathological contexts and discuss potential therapeutic approaches for addressing nuclear pore injury and dysfunctional nucleocytoplasmic transport.
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Affiliation(s)
- Charlotte M Fare
- Department of Neurology and Brain Science Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Jeffrey D Rothstein
- Department of Neurology and Brain Science Institute, Johns Hopkins University, Baltimore, MD, USA
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3
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Ravi J, Anantharaman V, Chen SZ, Brenner EP, Datta P, Aravind L, Gennaro ML. The phage shock protein (PSP) envelope stress response: discovery of novel partners and evolutionary history. mSystems 2024; 9:e0084723. [PMID: 38809013 DOI: 10.1128/msystems.00847-23] [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: 08/28/2023] [Accepted: 03/20/2024] [Indexed: 05/30/2024] Open
Abstract
Bacterial phage shock protein (PSP) systems stabilize the bacterial cell membrane and protect against envelope stress. These systems have been associated with virulence, but despite their critical roles, PSP components are not well characterized outside proteobacteria. Using comparative genomics and protein sequence-structure-function analyses, we systematically identified and analyzed PSP homologs, phyletic patterns, domain architectures, and gene neighborhoods. This approach underscored the evolutionary significance of the system, revealing that its core protein PspA (Snf7 in ESCRT outside bacteria) was present in the last universal common ancestor and that this ancestral functionality has since diversified into multiple novel, distinct PSP systems across life. Several novel partners of the PSP system were identified: (i) the Toastrack domain, likely facilitating assembly of sub-membrane stress-sensing and signaling complexes, (ii) the newly defined HTH-associated α-helical signaling domain-PadR-like transcriptional regulator pair system, and (iii) multiple independent associations with ATPase, CesT/Tir-like chaperone, and Band-7 domains in proteins thought to mediate sub-membrane dynamics. Our work also uncovered links between the PSP components and other domains, such as novel variants of SHOCT-like domains, suggesting roles in assembling membrane-associated complexes of proteins with disparate biochemical functions. Results are available at our interactive web app, https://jravilab.org/psp.IMPORTANCEPhage shock proteins (PSP) are virulence-associated, cell membrane stress-protective systems. They have mostly been characterized in Proteobacteria and Firmicutes. We now show that a minimal PSP system was present in the last universal common ancestor that evolved and diversified into newly identified functional contexts. Recognizing the conservation and evolution of PSP systems across bacterial phyla contributes to our understanding of stress response mechanisms in prokaryotes. Moreover, the newly discovered PSP modularity will likely prompt new studies of lineage-specific cell envelope structures, lifestyles, and adaptation mechanisms. Finally, our results validate the use of domain architecture and genetic context for discovery in comparative genomics.
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Affiliation(s)
- Janani Ravi
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Vivek Anantharaman
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, Maryland, USA
| | - Samuel Zorn Chen
- Computer Science Engineering Undergraduate Program, Michigan State University, East Lansing, Michigan, USA
| | - Evan Pierce Brenner
- Department of Biomedical Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Pratik Datta
- Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - L Aravind
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, Maryland, USA
| | - Maria Laura Gennaro
- Public Health Research Institute, Rutgers New Jersey Medical School, Newark, New Jersey, USA
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4
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Ikeda T, Yamazaki K, Okumura F, Kamura T, Nakatsukasa K. Role of the San1 ubiquitin ligase in the heat stress-induced degradation of nonnative Nup1 in the nuclear pore complex. Genetics 2024; 226:iyae017. [PMID: 38302116 DOI: 10.1093/genetics/iyae017] [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: 11/21/2022] [Revised: 11/21/2022] [Accepted: 01/23/2024] [Indexed: 02/03/2024] Open
Abstract
The nuclear pore complex (NPC) mediates the selective exchange of macromolecules between the nucleus and the cytoplasm. Neurodegenerative diseases such as amyotrophic lateral sclerosis are characterized by mislocalization of nucleoporins (Nups), transport receptors, and Ras-related nuclear proteins into nucleoplasmic or cytosolic aggregates, underscoring the importance of precise assembly of the NPC. The assembly state of large protein complexes is strictly monitored by the protein quality control system. The ubiquitin-proteasome system may eliminate aberrant, misfolded, and/or orphan components; however, the involvement of the ubiquitin-proteasome system in the degradation of nonnative Nups in the NPC remains unclear. Here, we show that in Saccharomyces cerevisiae, although Nup1 (the FG-Nup component of the central core of the NPC) was stable, C-terminally green fluorescent protein-tagged Nup1, which had been incorporated into the NPC, was degraded by the proteasome especially under heat stress conditions. The degradation was dependent on the San1 ubiquitin ligase and Cdc48/p97, as well as its cofactor Doa1. We also demonstrate that San1 weakly but certainly contributes to the degradation of nontagged endogenous Nup1 in cells defective in NPC biogenesis by the deletion of NUP120. In addition, the overexpression of SAN1 exacerbated the growth defect phenotype of nup120Δ cells, which may be caused by excess degradation of defective Nups due to the deletion of NUP120. These biochemical and genetic data suggest that San1 is involved in the degradation of nonnative Nups generated by genetic mutation or when NPC biogenesis is impaired.
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Affiliation(s)
- Takanari Ikeda
- Graduate School of Science, Nagoya City University, Nagoya, Aichi 467-8501, Japan
| | - Kenji Yamazaki
- Division of Biological Sciences, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Fumihiko Okumura
- Department of Food and Health Sciences, International College of Arts and Sciences, Fukuoka Women's University, Fukuoka, Fukuoka 813-8529, Japan
| | - Takumi Kamura
- Division of Biological Sciences, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Kunio Nakatsukasa
- Graduate School of Science, Nagoya City University, Nagoya, Aichi 467-8501, Japan
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5
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Mannino PJ, Perun A, Surovstev I, Ader NR, Shao L, Melia TJ, King MC, Lusk CP. A quantitative ultrastructural timeline of nuclear autophagy reveals a role for dynamin-like protein 1 at the nuclear envelope. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580336. [PMID: 38405892 PMCID: PMC10888867 DOI: 10.1101/2024.02.14.580336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Autophagic mechanisms that maintain nuclear envelope homeostasis are bulwarks to aging and disease. By leveraging 4D lattice light sheet microscopy and correlative light and electron tomography, we define a quantitative and ultrastructural timeline of a nuclear macroautophagy (nucleophagy) pathway in yeast. Nucleophagy initiates with a rapid local accumulation of the nuclear cargo adaptor Atg39 at the nuclear envelope adjacent to the nucleus-vacuole junction and is delivered to the vacuole in ~300 seconds through an autophagosome intermediate. Mechanistically, nucleophagy incorporates two consecutive and genetically defined membrane fission steps: inner nuclear membrane (INM) fission generates a lumenal vesicle in the perinuclear space followed by outer nuclear membrane (ONM) fission to liberate a double membraned vesicle to the cytosol. ONM fission occurs independently of phagophore engagement and instead relies surprisingly on dynamin-like protein1 (Dnm1), which is recruited to sites of Atg39 accumulation at the nuclear envelope. Loss of Dnm1 compromises nucleophagic flux by stalling nucleophagy after INM fission. Our findings reveal how nuclear and INM cargo are removed from an intact nucleus without compromising its integrity, achieved in part by a non-canonical role for Dnm1 in nuclear envelope remodeling.
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Affiliation(s)
- Philip J. Mannino
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Andrew Perun
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Ivan Surovstev
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
- Department of Physics, Yale University, New Haven, CT, 06511
| | - Nicholas R. Ader
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Lin Shao
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Thomas J. Melia
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
| | - Megan C. King
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT, 06511
| | - C. Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, 295 Congress Ave, New Haven, CT, 06520
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6
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Sule KC, Nakamura M, Parkhurst SM. Nuclear envelope budding: Getting large macromolecular complexes out of the nucleus. Bioessays 2024; 46:e2300182. [PMID: 38044581 PMCID: PMC10843589 DOI: 10.1002/bies.202300182] [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: 09/24/2023] [Revised: 11/19/2023] [Accepted: 11/21/2023] [Indexed: 12/05/2023]
Abstract
Transport of macromolecules from the nucleus to the cytoplasm is essential for nearly all cellular and developmental events, and when mis-regulated, is associated with diseases, tumor formation/growth, and cancer progression. Nuclear Envelope (NE)-budding is a newly appreciated nuclear export pathway for large macromolecular machineries, including those assembled to allow co-regulation of functionally related components, that bypasses canonical nuclear export through nuclear pores. In this pathway, large macromolecular complexes are enveloped by the inner nuclear membrane, transverse the perinuclear space, and then exit through the outer nuclear membrane to release its contents into the cytoplasm. NE-budding is a conserved process and shares many features with nuclear egress mechanisms used by herpesviruses. Despite its biological importance and clinical relevance, little is yet known about the regulatory and structural machineries that allow NE-budding to occur in any system. Here we summarize what is currently known or proposed for this intriguing nuclear export process.
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Affiliation(s)
- Kevin C. Sule
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA, USA 98109
| | - Mitsutoshi Nakamura
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA, USA 98109
| | - Susan M. Parkhurst
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA, USA 98109
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7
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Baskerville V, Rapuri S, Mehlhop E, Coyne AN. SUN1 facilitates CHMP7 nuclear influx and injury cascades in sporadic amyotrophic lateral sclerosis. Brain 2024; 147:109-121. [PMID: 37639327 PMCID: PMC10766250 DOI: 10.1093/brain/awad291] [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: 04/24/2023] [Revised: 07/16/2023] [Accepted: 08/07/2023] [Indexed: 08/31/2023] Open
Abstract
We have recently identified the aberrant nuclear accumulation of the ESCRT-III protein CHMP7 as an initiating event that leads to a significant injury to the nuclear pore complex (NPC) characterized by the reduction of specific nucleoporins from the neuronal NPC in sporadic amyotrophic lateral sclerosis (sALS) and C9orf72 ALS/frontotemporal dementia (FTD)-induced pluripotent stem cell-derived neurons (iPSNs), a phenomenon also observed in post-mortem patient tissues. Importantly, this NPC injury is sufficient to contribute to TDP-43 dysfunction and mislocalization, a common pathological hallmark of neurodegenerative diseases. However, the molecular mechanisms and events that give rise to increased nuclear translocation and/or retention of CHMP7 to initiate this pathophysiological cascade remain largely unknown. Here, using an iPSN model of sALS, we demonstrate that impaired NPC permeability barrier integrity and interactions with the LINC complex protein SUN1 facilitate CHMP7 nuclear localization and the subsequent 'activation' of NPC injury cascades. Collectively, our data provide mechanistic insights in the pathophysiological underpinnings of ALS/FTD and highlight SUN1 as a potent contributor to and modifier of CHMP7-mediated toxicity in sALS pathogenesis.
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Affiliation(s)
- Victoria Baskerville
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Sampath Rapuri
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Emma Mehlhop
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Alyssa N Coyne
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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8
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Baum B, Spang A. On the origin of the nucleus: a hypothesis. Microbiol Mol Biol Rev 2023; 87:e0018621. [PMID: 38018971 PMCID: PMC10732040 DOI: 10.1128/mmbr.00186-21] [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: 11/30/2023] Open
Abstract
SUMMARYIn this hypothesis article, we explore the origin of the eukaryotic nucleus. In doing so, we first look afresh at the nature of this defining feature of the eukaryotic cell and its core functions-emphasizing the utility of seeing the eukaryotic nucleoplasm and cytoplasm as distinct regions of a common compartment. We then discuss recent progress in understanding the evolution of the eukaryotic cell from archaeal and bacterial ancestors, focusing on phylogenetic and experimental data which have revealed that many eukaryotic machines with nuclear activities have archaeal counterparts. In addition, we review the literature describing the cell biology of representatives of the TACK and Asgardarchaeaota - the closest known living archaeal relatives of eukaryotes. Finally, bringing these strands together, we propose a model for the archaeal origin of the nucleus that explains much of the current data, including predictions that can be used to put the model to the test.
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Affiliation(s)
- Buzz Baum
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Anja Spang
- Department of Marine Microbiology and Biogeochemistry, NIOZ, Royal Netherlands Institute for Sea Research, Den Burg, the Netherlands
- Department of Evolutionary & Population Biology, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, the Netherlands
- Department of Marine Microbiology and Biogeochemistry, NIOZ, Royal Netherlands Institute for Sea Research, Den Burg, the Netherlands
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9
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Keuenhof KS, Kohler V, Broeskamp F, Panagaki D, Speese SD, Büttner S, Höög JL. Nuclear envelope budding and its cellular functions. Nucleus 2023; 14:2178184. [PMID: 36814098 PMCID: PMC9980700 DOI: 10.1080/19491034.2023.2178184] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 02/03/2023] [Indexed: 02/24/2023] Open
Abstract
The nuclear pore complex (NPC) has long been assumed to be the sole route across the nuclear envelope, and under normal homeostatic conditions it is indeed the main mechanism of nucleo-cytoplasmic transport. However, it has also been known that e.g. herpesviruses cross the nuclear envelope utilizing a pathway entitled nuclear egress or envelopment/de-envelopment. Despite this, a thread of observations suggests that mechanisms similar to viral egress may be transiently used also in healthy cells. It has since been proposed that mechanisms like nuclear envelope budding (NEB) can facilitate the transport of RNA granules, aggregated proteins, inner nuclear membrane proteins, and mis-assembled NPCs. Herein, we will summarize the known roles of NEB as a physiological and intrinsic cellular feature and highlight the many unanswered questions surrounding these intriguing nuclear events.
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Affiliation(s)
| | - Verena Kohler
- Institute of Molecular Biosciences, University of Graz, Austria
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Sweden
| | - Filomena Broeskamp
- Department for Chemistry and Molecular biology, University of Gothenburg, Sweden
| | - Dimitra Panagaki
- Department for Chemistry and Molecular biology, University of Gothenburg, Sweden
| | - Sean D. Speese
- Knight Cancer Early Detection Advanced Research Center, Oregon Health and Science University, 2720 S Moody Ave, Portland, OR, 97201, USA
| | - Sabrina Büttner
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Sweden
| | - Johanna L. Höög
- Department for Chemistry and Molecular biology, University of Gothenburg, Sweden
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10
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Veldsink AC, Gallardo P, Lusk CP, Veenhoff LM. Changing the guard-nuclear pore complex quality control. FEBS Lett 2023; 597:2739-2749. [PMID: 37715940 DOI: 10.1002/1873-3468.14739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/31/2023] [Accepted: 08/31/2023] [Indexed: 09/18/2023]
Abstract
The integrity of the nuclear envelope depends on the function of nuclear pore complexes (NPCs), transport channels that control macromolecular traffic between the nucleus and cytosol. The central importance of NPCs suggests the existence of quality control (QC) mechanisms that oversee their assembly and function. In this perspective, we emphasize the challenges associated with NPC assembly and the need for QC mechanisms that operate at various stages of an NPC's life. This includes cytosolic preassembly QC that helps enforce key nucleoporin-nucleoporin interactions and their ultimate stoichiometry in the NPC in addition to mechanisms that monitor aberrant fusion of the inner and outer nuclear membranes. Furthermore, we discuss whether and how these QC mechanisms may operate to sense faulty mature NPCs to facilitate their repair or removal. The so far uncovered mechanisms for NPC QC provide fertile ground for future research that not only benefits a better understanding of the vital role that NPCs play in cellular physiology but also how loss of NPC function and/or these QC mechanisms might be an input to aging and disease.
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Affiliation(s)
- Annemiek C Veldsink
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, Groningen, 9713 AV, The Netherlands
| | - Paola Gallardo
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, Groningen, 9713 AV, The Netherlands
| | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, CT, New Haven, USA
| | - Liesbeth M Veenhoff
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, Groningen, 9713 AV, The Netherlands
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11
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Ader NR, Chen L, Surovtsev IV, Chadwick WL, Rodriguez EC, King MC, Lusk CP. An ESCRT grommet cooperates with a diffusion barrier to maintain nuclear integrity. Nat Cell Biol 2023; 25:1465-1477. [PMID: 37783794 DOI: 10.1038/s41556-023-01235-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 08/17/2023] [Indexed: 10/04/2023]
Abstract
The molecular mechanisms by which the endosomal sorting complexes required for transport (ESCRT) proteins contribute to the integrity of the nuclear envelope (NE) barrier are not fully defined. We leveraged the single NE hole generated by mitotic extrusion of the Schizosaccharomyces pombe spindle pole body to reveal two modes of ESCRT function executed by distinct complements of ESCRT-III proteins, both dependent on CHMP7/Cmp7. A grommet-like function is required to restrict the NE hole in anaphase B, whereas replacement of Cmp7 by a sealing module ultimately closes the NE in interphase. Without Cmp7, nucleocytoplasmic compartmentalization remains intact despite NE discontinuities of up to 540 nm, suggesting mechanisms to limit diffusion through these holes. We implicate spindle pole body proteins as key components of a diffusion barrier acting with Cmp7 in anaphase B. Thus, NE remodelling mechanisms cooperate with proteinaceous diffusion barriers beyond nuclear pore complexes to maintain the nuclear compartment.
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Affiliation(s)
- Nicholas R Ader
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Linda Chen
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Ivan V Surovtsev
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
- Department of Physics, Yale University, New Haven, CT, USA
| | | | - Elisa C Rodriguez
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Megan C King
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA.
- Department of Molecular, Cell and Developmental Biology, Yale University, New Haven, CT, USA.
| | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA.
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12
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Shah H, Dey G. A diffusion barrier limits nuclear leaks. Nat Cell Biol 2023; 25:1411-1412. [PMID: 37783793 DOI: 10.1038/s41556-023-01243-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Affiliation(s)
- Hiral Shah
- Cell Biology and Biophysics, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Gautam Dey
- Cell Biology and Biophysics, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.
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13
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Cristi AC, Rapuri S, Coyne AN. Nuclear pore complex and nucleocytoplasmic transport disruption in neurodegeneration. FEBS Lett 2023; 597:2546-2566. [PMID: 37657945 PMCID: PMC10612469 DOI: 10.1002/1873-3468.14729] [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: 06/25/2023] [Revised: 07/29/2023] [Accepted: 08/24/2023] [Indexed: 09/03/2023]
Abstract
Nuclear pore complexes (NPCs) play a critical role in maintaining the equilibrium between the nucleus and cytoplasm, enabling bidirectional transport across the nuclear envelope, and are essential for proper nuclear organization and gene regulation. Perturbations in the regulatory mechanisms governing NPCs and nuclear envelope homeostasis have been implicated in the pathogenesis of several neurodegenerative diseases. The ESCRT-III pathway emerges as a critical player in the surveillance and preservation of well-assembled, functional NPCs, as well as nuclear envelope sealing. Recent studies have provided insights into the involvement of nuclear ESCRT-III in the selective reduction of specific nucleoporins associated with neurodegenerative pathologies. Thus, maintaining quality control of the nuclear envelope and NPCs represents a pivotal element in the pathological cascade leading to neurodegenerative diseases. This review describes the constituents of the nuclear-cytoplasmic transport machinery, encompassing the nuclear envelope, NPC, and ESCRT proteins, and how their structural and functional alterations contribute to the development of neurodegenerative diseases.
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Affiliation(s)
- América Chandía Cristi
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
| | - Sampath Rapuri
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
| | - Alyssa N Coyne
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
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14
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McGoldrick P, Robertson J. Unraveling the impact of disrupted nucleocytoplasmic transport systems in C9orf72-associated ALS. Front Cell Neurosci 2023; 17:1247297. [PMID: 37720544 PMCID: PMC10501458 DOI: 10.3389/fncel.2023.1247297] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 08/08/2023] [Indexed: 09/19/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two adult-onset neurodegenerative diseases that are part of a common disease spectrum due to clinical, genetic, and pathological overlap. A prominent genetic factor contributing to both diseases is a hexanucleotide repeat expansion in a non-coding region of the C9orf72 gene. This mutation in C9orf72 leads to nuclear depletion and cytoplasmic aggregation of Tar DNA-RNA binding protein 43 (TDP-43). TDP-43 pathology is characteristic of the majority of ALS cases, irrespective of disease causation, and is present in ~50% of FTD cases. Defects in nucleocytoplasmic transport involving the nuclear pore complex, the Ran-GTPase cycle, and nuclear transport factors have been linked with the mislocalization of TDP-43. Here, we will explore and discuss the implications of these system abnormalities of nucleocytoplasmic transport in C9orf72-ALS/FTD, as well as in other forms of familial and sporadic ALS.
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Affiliation(s)
- Philip McGoldrick
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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15
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de Oya IG, Manzano-López J, Álvarez-Llamas A, Vázquez-Aroca MDLP, Cepeda-García C, Monje-Casas F. Characterization of a novel interaction of the Nup159 nucleoporin with asymmetrically localized spindle pole body proteins and its link with autophagy. PLoS Biol 2023; 21:e3002224. [PMID: 37535687 PMCID: PMC10437821 DOI: 10.1371/journal.pbio.3002224] [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: 05/18/2022] [Revised: 08/18/2023] [Accepted: 06/28/2023] [Indexed: 08/05/2023] Open
Abstract
Both the spindle microtubule-organizing centers and the nuclear pore complexes (NPCs) are convoluted structures where many signaling pathways converge to coordinate key events during cell division. Interestingly, despite their distinct molecular conformation and overall functions, these structures share common components and collaborate in the regulation of essential processes. We have established a new link between microtubule-organizing centers and nuclear pores in budding yeast by unveiling an interaction between the Bfa1/Bub2 complex, a mitotic exit inhibitor that localizes on the spindle pole bodies, and the Nup159 nucleoporin. Bfa1/Bub2 association with Nup159 is reduced in metaphase to not interfere with proper spindle positioning. However, their interaction is stimulated in anaphase and assists the Nup159-dependent autophagy pathway. The asymmetric localization of Bfa1/Bub2 during mitosis raises the possibility that its interaction with Nup159 could differentially promote Nup159-mediated autophagic processes, which might be relevant for the maintenance of the replicative lifespan.
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Affiliation(s)
- Inés García de Oya
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
| | - Javier Manzano-López
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
| | - Alejandra Álvarez-Llamas
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
| | - María de la Paz Vázquez-Aroca
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
| | - Cristina Cepeda-García
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
| | - Fernando Monje-Casas
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER) / Spanish National Research Council (CSIC) - University of Seville - University Pablo de Olavide, Sevilla, Spain
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16
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Santana-Sosa S, Matos-Perdomo E, Ayra-Plasencia J, Machín F. A Yeast Mitotic Tale for the Nucleus and the Vacuoles to Embrace. Int J Mol Sci 2023; 24:9829. [PMID: 37372977 DOI: 10.3390/ijms24129829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/02/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
The morphology of the nucleus is roughly spherical in most eukaryotic cells. However, this organelle shape needs to change as the cell travels through narrow intercellular spaces during cell migration and during cell division in organisms that undergo closed mitosis, i.e., without dismantling the nuclear envelope, such as yeast. In addition, the nuclear morphology is often modified under stress and in pathological conditions, being a hallmark of cancer and senescent cells. Thus, understanding nuclear morphological dynamics is of uttermost importance, as pathways and proteins involved in nuclear shaping can be targeted in anticancer, antiaging, and antifungal therapies. Here, we review how and why the nuclear shape changes during mitotic blocks in yeast, introducing novel data that associate these changes with both the nucleolus and the vacuole. Altogether, these findings suggest a close relationship between the nucleolar domain of the nucleus and the autophagic organelle, which we also discuss here. Encouragingly, recent evidence in tumor cell lines has linked aberrant nuclear morphology to defects in lysosomal function.
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Affiliation(s)
- Silvia Santana-Sosa
- Research Unit, University Hospital Ntra Sra de Candelaria, Ctra del Rosario 145, 38010 Santa Cruz de Tenerife, Spain
- Institute of Biomedical Technologies, University of La Laguna, 38200 San Cristóbal de La Laguna, Spain
| | - Emiliano Matos-Perdomo
- Research Unit, University Hospital Ntra Sra de Candelaria, Ctra del Rosario 145, 38010 Santa Cruz de Tenerife, Spain
- Institute of Biomedical Technologies, University of La Laguna, 38200 San Cristóbal de La Laguna, Spain
| | - Jessel Ayra-Plasencia
- Research Unit, University Hospital Ntra Sra de Candelaria, Ctra del Rosario 145, 38010 Santa Cruz de Tenerife, Spain
- Institute of Biomedical Technologies, University of La Laguna, 38200 San Cristóbal de La Laguna, Spain
| | - Félix Machín
- Research Unit, University Hospital Ntra Sra de Candelaria, Ctra del Rosario 145, 38010 Santa Cruz de Tenerife, Spain
- Institute of Biomedical Technologies, University of La Laguna, 38200 San Cristóbal de La Laguna, Spain
- Faculty of Health Sciences, Fernando Pessoa Canarias University, 35450 Santa María de Guía, Spain
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17
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Sengupta S, Pick E. The Ubiquitin-like Proteins of Saccharomyces cerevisiae. Biomolecules 2023; 13:biom13050734. [PMID: 37238603 DOI: 10.3390/biom13050734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/18/2023] [Accepted: 04/21/2023] [Indexed: 05/28/2023] Open
Abstract
In this review, we present a comprehensive list of the ubiquitin-like modifiers (Ubls) of Saccharomyces cerevisiae, a common model organism used to study fundamental cellular processes that are conserved in complex multicellular organisms, such as humans. Ubls are a family of proteins that share structural relationships with ubiquitin, and which modify target proteins and lipids. These modifiers are processed, activated and conjugated to substrates by cognate enzymatic cascades. The attachment of substrates to Ubls alters the various properties of these substrates, such as function, interaction with the environment or turnover, and accordingly regulate key cellular processes, including DNA damage, cell cycle progression, metabolism, stress response, cellular differentiation, and protein homeostasis. Thus, it is not surprising that Ubls serve as tools to study the underlying mechanism involved in cellular health. We summarize current knowledge on the activity and mechanism of action of the S. cerevisiae Rub1, Smt3, Atg8, Atg12, Urm1 and Hub1 modifiers, all of which are highly conserved in organisms from yeast to humans.
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Affiliation(s)
- Swarnab Sengupta
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa Mount Carmel, Haifa 3498838, Israel
| | - Elah Pick
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa Mount Carmel, Haifa 3498838, Israel
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon 3600600, Israel
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18
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Zeng Y, Li B, Huang S, Li H, Cao W, Chen Y, Liu G, Li Z, Yang C, Feng L, Gao J, Lo SW, Zhao J, Shen J, Guo Y, Gao C, Dagdas Y, Jiang L. The plant unique ESCRT component FREE1 regulates autophagosome closure. Nat Commun 2023; 14:1768. [PMID: 36997511 PMCID: PMC10063618 DOI: 10.1038/s41467-023-37185-6] [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: 03/15/2022] [Accepted: 03/03/2023] [Indexed: 04/01/2023] Open
Abstract
The energy sensor AMP-activated protein kinase (AMPK) can activate autophagy when cellular energy production becomes compromised. However, the degree to which nutrient sensing impinges on the autophagosome closure remains unknown. Here, we provide the mechanism underlying a plant unique protein FREE1, upon autophagy-induced SnRK1α1-mediated phosphorylation, functions as a linkage between ATG conjugation system and ESCRT machinery to regulate the autophagosome closure upon nutrient deprivation. Using high-resolution microscopy, 3D-electron tomography, and protease protection assay, we showed that unclosed autophagosomes accumulated in free1 mutants. Proteomic, cellular and biochemical analysis revealed the mechanistic connection between FREE1 and the ATG conjugation system/ESCRT-III complex in regulating autophagosome closure. Mass spectrometry analysis showed that the evolutionary conserved plant energy sensor SnRK1α1 phosphorylates FREE1 and recruits it to the autophagosomes to promote closure. Mutagenesis of the phosphorylation site on FREE1 caused the autophagosome closure failure. Our findings unveil how cellular energy sensing pathways regulate autophagosome closure to maintain cellular homeostasis.
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Affiliation(s)
- Yonglun Zeng
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Baiying Li
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Shuxian Huang
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Hongbo Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Wenhan Cao
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Yixuan Chen
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Guoyong Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Zhenping Li
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Chao Yang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Lei Feng
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Jiayang Gao
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Sze Wan Lo
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Jierui Zhao
- Vienna BioCenter PhD Program, Doctoral School of the University at Vienna and Medical University of Vienna, Vienna, Austria
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Vienna, Austria
| | - Jinbo Shen
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
| | - Yan Guo
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Caiji Gao
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Yasin Dagdas
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Vienna, Austria
| | - Liwen Jiang
- Centre for Cell & Developmental Biology and State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China.
- CUHK Shenzhen Research Institute, Shenzhen, China.
- Institute of Plant Molecular Biology and Agricultural Biotechnology, The Chinese University of Hong Kong, Hong Kong, China.
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19
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Suzuki N, Nishiyama A, Warita H, Aoki M. Genetics of amyotrophic lateral sclerosis: seeking therapeutic targets in the era of gene therapy. J Hum Genet 2023; 68:131-152. [PMID: 35691950 PMCID: PMC9968660 DOI: 10.1038/s10038-022-01055-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/17/2022] [Accepted: 05/29/2022] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is an intractable disease that causes respiratory failure leading to mortality. The main locus of ALS is motor neurons. The success of antisense oligonucleotide (ASO) therapy in spinal muscular atrophy (SMA), a motor neuron disease, has triggered a paradigm shift in developing ALS therapies. The causative genes of ALS and disease-modifying genes, including those of sporadic ALS, have been identified one after another. Thus, the freedom of target choice for gene therapy has expanded by ASO strategy, leading to new avenues for therapeutic development. Tofersen for superoxide dismutase 1 (SOD1) was a pioneer in developing ASO for ALS. Improving protocols and devising early interventions for the disease are vital. In this review, we updated the knowledge of causative genes in ALS. We summarized the genetic mutations identified in familial ALS and their clinical features, focusing on SOD1, fused in sarcoma (FUS), and transacting response DNA-binding protein. The frequency of the C9ORF72 mutation is low in Japan, unlike in Europe and the United States, while SOD1 and FUS are more common, indicating that the target mutations for gene therapy vary by ethnicity. A genome-wide association study has revealed disease-modifying genes, which could be the novel target of gene therapy. The current status and prospects of gene therapy development were discussed, including ethical issues. Furthermore, we discussed the potential of axonal pathology as new therapeutic targets of ALS from the perspective of early intervention, including intra-axonal transcription factors, neuromuscular junction disconnection, dysregulated local translation, abnormal protein degradation, mitochondrial pathology, impaired axonal transport, aberrant cytoskeleton, and axon branching. We simultaneously discuss important pathological states of cell bodies: persistent stress granules, disrupted nucleocytoplasmic transport, and cryptic splicing. The development of gene therapy based on the elucidation of disease-modifying genes and early intervention in molecular pathology is expected to become an important therapeutic strategy in ALS.
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Affiliation(s)
- Naoki Suzuki
- Department of Neurology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Japan.
| | - Ayumi Nishiyama
- Department of Neurology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Japan
| | - Hitoshi Warita
- Department of Neurology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Japan
| | - Masashi Aoki
- Department of Neurology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Japan.
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20
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Harrer P, Schalk A, Shimura M, Baer S, Calmels N, Spitz MA, Warde MTA, Schaefer E, Kittke VMS, Dincer Y, Wagner M, Dzinovic I, Berutti R, Sato T, Shirakawa T, Okazaki Y, Murayama K, Oexle K, Prokisch H, Mall V, Melčák I, Winkelmann J, Zech M. Recessive NUP54 Variants Underlie Early-Onset Dystonia with Striatal Lesions. Ann Neurol 2023; 93:330-335. [PMID: 36333996 DOI: 10.1002/ana.26544] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/31/2022] [Accepted: 11/03/2022] [Indexed: 11/06/2022]
Abstract
Infantile striatonigral degeneration is caused by a homozygous variant of the nuclear-pore complex (NPC) gene NUP62, involved in nucleo-cytoplasmic trafficking. By querying sequencing-datasets of patients with dystonia and/or Leigh(-like) syndromes, we identified 3 unrelated individuals with biallelic variants in NUP54. All variants clustered in the C-terminal protein region that interacts with NUP62. Associated phenotypes were similar to those of NUP62-related disease, including early-onset dystonia with dysphagia, choreoathetosis, and T2-hyperintense lesions in striatum. In silico and protein-biochemical studies gave further evidence for the argument that the variants were pathogenic. We expand the spectrum of NPC component-associated dystonic conditions with localized basal-ganglia abnormalities. ANN NEUROL 2023;93:330-335.
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Affiliation(s)
- Philip Harrer
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Audrey Schalk
- Institut de génétique médicale d'Alsace (IGMA), Laboratoires de Diagnostic Génétique, Hôpitaux universitaires de Strasbourg, Strasbourg, France
| | - Masaru Shimura
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Center for Medical Genetics, Department of Metabolism, Chiba Children's Hospital, Chiba, Japan
| | - Sarah Baer
- Department of Neuropediatrics, ERN EpiCare, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.,Institute for Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France
| | - Nadège Calmels
- Institut de génétique médicale d'Alsace (IGMA), Laboratoires de Diagnostic Génétique, Hôpitaux universitaires de Strasbourg, Strasbourg, France.,Laboratoire de Génétique Médicale, INSERM U1112, Institut de génétique médicale d'Alsace, CRBS, Strasbourg, France
| | - Marie Aude Spitz
- Department of Neuropediatrics, ERN EpiCare, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Marie-Thérèse Abi Warde
- Department of Neuropediatrics, ERN EpiCare, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Elise Schaefer
- Service de Génétique Médicale, Institut de Génétique Médicale d'Alsace (IGMA), Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Volker M Sc Kittke
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Yasemin Dincer
- Lehrstuhl für Sozialpädiatrie, Department of Pediatrics, Technische Universität München, Munich, Germany.,Zentrum für Humangenetik und Laboratoriumsdiagnostik (MVZ), Martinsried, Germany
| | - Matias Wagner
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Ivana Dzinovic
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Riccardo Berutti
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Tatsuharu Sato
- Department of Pediatrics, Nagasaki University Hospital, Nagasaki, Japan
| | | | - Yasushi Okazaki
- Diagnostics and Therapeutic of Intractable Diseases, Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | - Kei Murayama
- Center for Medical Genetics, Department of Metabolism, Chiba Children's Hospital, Chiba, Japan.,Diagnostics and Therapeutic of Intractable Diseases, Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | - Konrad Oexle
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Holger Prokisch
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Volker Mall
- Lehrstuhl für Sozialpädiatrie, Department of Pediatrics, Technische Universität München, Munich, Germany.,kbo-Kinderzentrum München, Munich, Germany
| | - Ivo Melčák
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory School of Medicine, Atlanta, Georgia, USA
| | - Juliane Winkelmann
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany.,Lehrstuhl für Neurogenetik, Technische Universität München, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Michael Zech
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany.,Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
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21
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Dubey SK, Maulding K, Sung H, Lloyd TE. Nucleoporins are degraded via upregulation of ESCRT-III/Vps4 complex in Drosophila models of C9-ALS/FTD. Cell Rep 2022; 40:111379. [PMID: 36130523 PMCID: PMC10099287 DOI: 10.1016/j.celrep.2022.111379] [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: 08/03/2021] [Revised: 03/22/2022] [Accepted: 08/28/2022] [Indexed: 11/03/2022] Open
Abstract
Disruption of the nuclear pore complex (NPC) and nucleocytoplasmic transport (NCT) have been implicated in the pathogenesis of neurodegenerative diseases. A GGGGCC hexanucleotide repeat expansion (HRE) in an intron of the C9orf72 gene is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia, but the mechanism by which the HRE disrupts NCT is incompletely understood. We find that expression of GGGGCC repeats in Drosophila neurons induces proteasome-mediated degradation of select nucleoporins of the NPC. This process requires the Vps4 ATPase and the endosomal-sorting complex required for transport complex-III (ESCRT-III), as knockdown of ESCRT-III/Vps4 genes rescues nucleoporin levels, normalizes NCT, and suppresses GGGGCC-mediated neurodegeneration. GGGGCC expression upregulates nuclear ESCRT-III/Vps4 expression, and expansion microscopy demonstrates that the nucleoporins are translocated into the cytoplasm before undergoing proteasome-mediated degradation. These findings demonstrate a mechanism for nucleoporin degradation and NPC dysfunction in neurodegenerative disease.
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Affiliation(s)
- Sandeep Kumar Dubey
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kirstin Maulding
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Cellular and Molecular Medicine Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hyun Sung
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Thomas E Lloyd
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Cellular and Molecular Medicine Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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22
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Borah S, Dhanasekaran K, Kumar S. The LEM-ESCRT toolkit: Repair and maintenance of the nucleus. Front Cell Dev Biol 2022; 10:989217. [PMID: 36172278 PMCID: PMC9512039 DOI: 10.3389/fcell.2022.989217] [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: 07/08/2022] [Accepted: 08/24/2022] [Indexed: 12/04/2022] Open
Abstract
The eukaryotic genome is enclosed in a nuclear envelope that protects it from potentially damaging cellular activities and physically segregates transcription and translation.Transport across the NE is highly regulated and occurs primarily via the macromolecular nuclear pore complexes.Loss of nuclear compartmentalization due to defects in NPC function and NE integrity are tied to neurological and ageing disorders like Alzheimer’s, viral pathogenesis, immune disorders, and cancer progression.Recent work implicates inner-nuclear membrane proteins of the conserved LEM domain family and the ESCRT machinery in NE reformation during cell division and NE repair upon rupture in migrating cancer cells, and generating seals over defective NPCs. In this review, we discuss the recent in-roads made into defining the molecular mechanisms and biochemical networks engaged by LEM and many other integral inner nuclear membrane proteins to preserve the nuclear barrier.
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Affiliation(s)
- Sapan Borah
- National Institute of Immunohaematology, Mumbai, Maharashtra, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
| | - Karthigeyan Dhanasekaran
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, Haryana, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
| | - Santosh Kumar
- National Centre for Cell Science, Pune, Maharashtra, India
- *Correspondence: Sapan Borah, ; Karthigeyan Dhanasekaran, ; Santosh Kumar,
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23
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Mannino PJ, Lusk CP. Quality control mechanisms that protect nuclear envelope identity and function. J Biophys Biochem Cytol 2022; 221:213424. [PMID: 36036741 PMCID: PMC9442147 DOI: 10.1083/jcb.202205123] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 11/22/2022] Open
Abstract
The nuclear envelope (NE) is a specialization of the endoplasmic reticulum with distinct biochemistry that defines inner and outer membranes connected at a pore membrane that houses nuclear pore complexes (NPCs). Quality control mechanisms that maintain the physical integrity and biochemical identity of these membranes are critical to ensure that the NE acts as a selective barrier that also contributes to genome stability and metabolism. As the proteome of the NE is highly integrated, it is challenging to turn over by conventional ubiquitin-proteasome and autophagy mechanisms. Further, removal of entire sections of the NE requires elaborate membrane remodeling that is poorly understood. Nonetheless, recent work has made inroads into discovering specializations of cellular degradative machineries tailored to meeting the unique challenges imposed by the NE. In addition, cells have evolved mechanisms to surveil and repair the NE barrier to protect against the deleterious effects of a breach in NE integrity, in the form of either a ruptured NE or a dysfunctional NPC. Here, we synthesize the most recent work exploring NE quality control mechanisms across eukaryotes.
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24
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The ESCRT Machinery: Remodeling, Repairing, and Sealing Membranes. MEMBRANES 2022; 12:membranes12060633. [PMID: 35736340 PMCID: PMC9229795 DOI: 10.3390/membranes12060633] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/16/2022] [Accepted: 06/17/2022] [Indexed: 01/27/2023]
Abstract
The ESCRT machinery is an evolutionarily conserved membrane remodeling complex that is used by the cell to perform reverse membrane scission in essential processes like protein degradation, cell division, and release of enveloped retroviruses. ESCRT-III, together with the AAA ATPase VPS4, harbors the main remodeling and scission function of the ESCRT machinery, whereas early-acting ESCRTs mainly contribute to protein sorting and ESCRT-III recruitment through association with upstream targeting factors. Here, we review recent advances in our understanding of the molecular mechanisms that underlie membrane constriction and scission by ESCRT-III and describe the involvement of this machinery in the sealing and repairing of damaged cellular membranes, a key function to preserve cellular viability and organellar function.
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25
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Hatano T, Palani S, Papatziamou D, Salzer R, Souza DP, Tamarit D, Makwana M, Potter A, Haig A, Xu W, Townsend D, Rochester D, Bellini D, Hussain HMA, Ettema TJG, Löwe J, Baum B, Robinson NP, Balasubramanian M. Asgard archaea shed light on the evolutionary origins of the eukaryotic ubiquitin-ESCRT machinery. Nat Commun 2022; 13:3398. [PMID: 35697693 PMCID: PMC9192718 DOI: 10.1038/s41467-022-30656-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 05/10/2022] [Indexed: 11/23/2022] Open
Abstract
The ESCRT machinery, comprising of multiple proteins and subcomplexes, is crucial for membrane remodelling in eukaryotic cells, in processes that include ubiquitin-mediated multivesicular body formation, membrane repair, cytokinetic abscission, and virus exit from host cells. This ESCRT system appears to have simpler, ancient origins, since many archaeal species possess homologues of ESCRT-III and Vps4, the components that execute the final membrane scission reaction, where they have been shown to play roles in cytokinesis, extracellular vesicle formation and viral egress. Remarkably, metagenome assemblies of Asgard archaea, the closest known living relatives of eukaryotes, were recently shown to encode homologues of the entire cascade involved in ubiquitin-mediated membrane remodelling, including ubiquitin itself, components of the ESCRT-I and ESCRT-II subcomplexes, and ESCRT-III and Vps4. Here, we explore the phylogeny, structure, and biochemistry of Asgard homologues of the ESCRT machinery and the associated ubiquitylation system. We provide evidence for the ESCRT-I and ESCRT-II subcomplexes being involved in ubiquitin-directed recruitment of ESCRT-III, as it is in eukaryotes. Taken together, our analyses suggest a pre-eukaryotic origin for the ubiquitin-coupled ESCRT system and a likely path of ESCRT evolution via a series of gene duplication and diversification events.
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Grants
- MC_U105184326 Medical Research Council
- MC_UP_1201/27 Medical Research Council
- 203276/Z/16/Z Wellcome Trust
- Wellcome Trust
- WT101885MA Wellcome Trust
- Wellcome Trust (Wellcome)
- Leverhulme Trust
- Svenska Forskningsrådet Formas (Swedish Research Council Formas)
- Above funding attributed to the authors as follows (from paper acknowledgements): Computational analysis was facilitated by resources provided by the Swedish National Infrastructure for Computing (SNIC) at the Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX), partially funded by the Swedish Research Council through grant agreement no. 2018-05973. We thank the Warwick Proteomics RTP for mass spectrometry. MKB was supported by the Wellcome Trust (WT101885MA) and the European Research Council (ERC-2014-ADG No. 671083). Work by the NR laboratory was supported by start-up funds from the Division of Biomedical and Life Sciences (BLS, Lancaster University) and a Leverhulme Research Project Grant (RPG-2019-297). NR would like to thank Johanna Syrjanen for performing trial expressions of the Odinarchaeota ESCRT proteins, and Joseph Maman for helpful discussion regarding the SEC-MALS. NR, WX and AP would like to thank Charley Lai and Siu-Kei Yau for assistance with initial Odinarchaeota ESCRT protein purifications. DPS and BB would like to thank Chris Johnson at the MRC LMB Biophysics facility for performing the SEC-MALS assay on Heimdallarchaeotal Vps22. TH, HH, MB, RS, JL, D Tamarit, TE, DPS and BB received support from a Wellcome Trust collaborative award (203276/Z/16/Z). BB and DPS were supported by the MRC. D Tamarit was supported by the Swedish Research Council (International Postdoc grant 2018-06609).
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Affiliation(s)
- Tomoyuki Hatano
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
| | - Saravanan Palani
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Dimitra Papatziamou
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Ralf Salzer
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Diorge P Souza
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Daniel Tamarit
- Laboratory of Microbiology, Wageningen University, 6708 WE, Wageningen, The Netherlands
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, SE-75007, Uppsala, Sweden
| | - Mehul Makwana
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Antonia Potter
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Alexandra Haig
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Wenjue Xu
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - David Townsend
- Department of Chemistry, Lancaster University, Lancaster, LA1 4YB, UK
| | - David Rochester
- Department of Chemistry, Lancaster University, Lancaster, LA1 4YB, UK
| | - Dom Bellini
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Hamdi M A Hussain
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
| | - Thijs J G Ettema
- Laboratory of Microbiology, Wageningen University, 6708 WE, Wageningen, The Netherlands
| | - Jan Löwe
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Buzz Baum
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK.
| | - Nicholas P Robinson
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK.
| | - Mohan Balasubramanian
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK.
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26
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Coyne AN, Rothstein JD. Nuclear pore complexes - a doorway to neural injury in neurodegeneration. Nat Rev Neurol 2022; 18:348-362. [PMID: 35488039 PMCID: PMC10015220 DOI: 10.1038/s41582-022-00653-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2022] [Indexed: 12/13/2022]
Abstract
The genetic underpinnings and end-stage pathological hallmarks of neurodegenerative diseases are increasingly well defined, but the cellular pathophysiology of disease initiation and propagation remains poorly understood, especially in sporadic forms of these diseases. Altered nucleocytoplasmic transport is emerging as a prominent pathomechanism of multiple neurodegenerative diseases, including amyotrophic lateral sclerosis, Alzheimer disease, frontotemporal dementia and Huntington disease. The nuclear pore complex (NPC) and interactions between its individual nucleoporin components and nuclear transport receptors regulate nucleocytoplasmic transport, as well as genome organization and gene expression. Specific nucleoporin abnormalities have been identified in sporadic and familial forms of neurodegenerative disease, and these alterations are thought to contribute to disrupted nucleocytoplasmic transport. The specific nucleoporins and nucleocytoplasmic transport proteins that have been linked to different neurodegenerative diseases are partially distinct, suggesting that NPC injury contributes to the cellular specificity of neurodegenerative disease and could be an early initiator of the pathophysiological cascades that underlie neurodegenerative disease. This concept is consistent with the fact that rare genetic mutations in some nucleoporins cause cell-type-specific neurological disease. In this Review, we discuss nucleoporin and NPC disruptions and consider their impact on cellular function and the pathophysiology of neurodegenerative disease.
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Affiliation(s)
- Alyssa N Coyne
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Jeffrey D Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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27
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The Nuclear Pore Complex: Birth, Life, and Death of a Cellular Behemoth. Cells 2022; 11:cells11091456. [PMID: 35563762 PMCID: PMC9100368 DOI: 10.3390/cells11091456] [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: 03/31/2022] [Revised: 04/22/2022] [Accepted: 04/23/2022] [Indexed: 02/01/2023] Open
Abstract
Nuclear pore complexes (NPCs) are the only transport channels that cross the nuclear envelope. Constructed from ~500–1000 nucleoporin proteins each, they are among the largest macromolecular assemblies in eukaryotic cells. Thanks to advances in structural analysis approaches, the construction principles and architecture of the NPC have recently been revealed at submolecular resolution. Although the overall structure and inventory of nucleoporins are conserved, NPCs exhibit significant compositional and functional plasticity even within single cells and surprising variability in their assembly pathways. Once assembled, NPCs remain seemingly unexchangeable in post-mitotic cells. There are a number of as yet unresolved questions about how the versatility of NPC assembly and composition is established, how cells monitor the functional state of NPCs or how they could be renewed. Here, we review current progress in our understanding of the key aspects of NPC architecture and lifecycle.
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28
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Meinema AC, Marzelliusardottir A, Mirkovic M, Aspert T, Lee SS, Charvin G, Barral Y. DNA circles promote yeast ageing in part through stimulating the reorganization of nuclear pore complexes. eLife 2022; 11:71196. [PMID: 35373738 PMCID: PMC9020822 DOI: 10.7554/elife.71196] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 04/03/2022] [Indexed: 11/13/2022] Open
Abstract
The nuclear pore complex (NPC) mediates nearly all exchanges between nucleus and cytoplasm, and in many species it changes composition as the organism ages. However, how these changes arise and whether they contribute themselves to ageing is poorly understood. We show that SAGA-dependent attachment of DNA circles to NPCs in replicatively ageing yeast cells causes NPCs to lose their nuclear basket and cytoplasmic complexes. These NPCs were not recognized as defective by the NPC quality control machinery (SINC) and not targeted by ESCRTs. They interacted normally or more effectively with protein import and export factors but specifically lost mRNA export factors. Acetylation of Nup60 drove the displacement of basket and cytoplasmic complexes from circle-bound NPCs. Mutations preventing this remodeling extended the replicative lifespan of the cells. Thus, our data suggest that the anchorage of accumulating circles locks NPCs in a specialized state and that this process is intrinsically linked to the mechanisms by which ERCs promote ageing.
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Affiliation(s)
| | | | | | - Théo Aspert
- Department of Developmental Biology and Stem Cells, Institute of Genetics and Molecular and Cellular Biology, Illkirch, France
| | - Sung Sik Lee
- Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Gilles Charvin
- Department of Developmental Biology and Stem Cells, Institute of Genetics and Molecular and Cellular Biology, Illkirch, France
| | - Yves Barral
- Department of Biology, ETH Zürich, Zürich, Switzerland
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29
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Raices M, D'Angelo MA. Structure, Maintenance, and Regulation of Nuclear Pore Complexes: The Gatekeepers of the Eukaryotic Genome. Cold Spring Harb Perspect Biol 2022; 14:a040691. [PMID: 34312247 PMCID: PMC8789946 DOI: 10.1101/cshperspect.a040691] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In eukaryotic cells, the genetic material is segregated inside the nucleus. This compartmentalization of the genome requires a transport system that allows cells to move molecules across the nuclear envelope, the membrane-based barrier that surrounds the chromosomes. Nuclear pore complexes (NPCs) are the central component of the nuclear transport machinery. These large protein channels penetrate the nuclear envelope, creating a passage between the nucleus and the cytoplasm through which nucleocytoplasmic molecule exchange occurs. NPCs are one of the largest protein assemblies of eukaryotic cells and, in addition to their critical function in nuclear transport, these structures also play key roles in many cellular processes in a transport-independent manner. Here we will review the current knowledge of the NPC structure, the cellular mechanisms that regulate their formation and maintenance, and we will provide a brief description of a variety of processes that NPCs regulate.
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Affiliation(s)
- Marcela Raices
- Cell and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, USA
| | - Maximiliano A D'Angelo
- Cell and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, USA
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30
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Deolal P, Jamir I, Mishra K. Uip4p modulates nuclear pore complex function in Saccharomyces cerevisiae. Nucleus 2022; 13:79-93. [PMID: 35171083 PMCID: PMC8855845 DOI: 10.1080/19491034.2022.2034286] [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] [Indexed: 11/11/2022] Open
Abstract
A double membrane bilayer perforated by nuclear pore complexes (NPCs) governs the shape of the nucleus, the prominent distinguishing organelle of a eukaryotic cell. Despite the absence of lamins in yeasts, the nuclear morphology is stably maintained and shape changes occur in a regulated fashion. In a quest to identify factors that contribute to regulation of nuclear shape and function in Saccharomyces cerevisiae, we used a fluorescence imaging based approach. Here we report the identification of a novel protein, Uip4p, that is required for regulation of nuclear morphology. Loss of Uip4 compromises NPC function and loss of nuclear envelope (NE) integrity. Our localization studies show that Uip4 localizes to the NE and endoplasmic reticulum (ER) network. Furthermore, we demonstrate that the localization and expression of Uip4 is regulated during growth, which is crucial for NPC distribution.
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Affiliation(s)
- Pallavi Deolal
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Imlitoshi Jamir
- Department of Biotechnology, School of Engineering and Technology, Nagaland University, Dimapur, India
| | - Krishnaveni Mishra
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
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31
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Buysse D, West M, Leih M, Odorizzi G. Bro1 binds the Vps20 subunit of ESCRT-III and promotes ESCRT-III regulation by Doa4. Traffic 2022; 23:109-119. [PMID: 34908216 PMCID: PMC8792227 DOI: 10.1111/tra.12828] [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: 06/26/2021] [Revised: 11/19/2021] [Accepted: 12/09/2021] [Indexed: 02/03/2023]
Abstract
The budding of intralumenal vesicles (ILVs) at endosomes requires membrane scission by the ESCRT-III complex. This step is negatively regulated in yeast by Doa4, the ubiquitin hydrolase that deubiquitinates transmembrane proteins sorted as cargoes into ILVs. Doa4 acts non-enzymatically to inhibit ESCRT-III membrane scission activity by directly binding the Snf7 subunit of ESCRT-III. This interaction inhibits the remodeling/disassembly of Snf7 polymers required for the ILV membrane scission reaction. Thus, Doa4 is thought to have a structural role that delays ILV budding while it also functions enzymatically to deubiquitinate ILV cargoes. In this study, we show that Doa4 binding to Snf7 in vivo is antagonized by another ESCRT-III subunit, Vps20. Doa4 is restricted from interacting with Snf7 in yeast expressing a mutant Vps20 allele that constitutively binds Doa4. This inhibitory effect of Vps20 is suppressed by overexpression of another ESCRT-III-associated protein, Bro1. We show that Bro1 binds directly to Vps20, suggesting that Bro1 has a central role in relieving the antagonistic relationship that Vps20 has toward Doa4.
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Affiliation(s)
- Dalton Buysse
- Department of Molecular Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Matt West
- Department of Molecular Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Mitchell Leih
- Department of Molecular Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Greg Odorizzi
- Department of Molecular Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309, USA,Author for correspondence ()
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32
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Emerging Connections between Nuclear Pore Complex Homeostasis and ALS. Int J Mol Sci 2022; 23:ijms23031329. [PMID: 35163252 PMCID: PMC8835831 DOI: 10.3390/ijms23031329] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/17/2022] [Accepted: 01/20/2022] [Indexed: 12/26/2022] Open
Abstract
Developing effective treatments for neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) requires understanding of the underlying pathomechanisms that contribute to the motor neuron loss that defines the disease. As it causes the largest fraction of familial ALS cases, considerable effort has focused on hexanucleotide repeat expansions in the C9ORF72 gene, which encode toxic repeat RNA and dipeptide repeat (DPR) proteins. Both the repeat RNA and DPRs interact with and perturb multiple elements of the nuclear transport machinery, including shuttling nuclear transport receptors, the Ran GTPase and the nucleoporin proteins (nups) that build the nuclear pore complex (NPC). Here, we consider recent work that describes changes to the molecular composition of the NPC in C9ORF72 model and patient neurons in the context of quality control mechanisms that function at the nuclear envelope (NE). For example, changes to NPC structure may be caused by the dysregulation of a conserved NE surveillance pathway mediated by the endosomal sorting complexes required for the transport protein, CHMP7. Thus, these studies are introducing NE and NPC quality control pathways as key elements in a pathological cascade that leads to C9ORF72 ALS, opening entirely new experimental avenues and possibilities for targeted therapeutic intervention.
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33
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Mochida K, Otani T, Katsumata Y, Kirisako H, Kakuta C, Kotani T, Nakatogawa H. Atg39 links and deforms the outer and inner nuclear membranes in selective autophagy of the nucleus. J Cell Biol 2022; 221:212974. [PMID: 35061008 PMCID: PMC8789198 DOI: 10.1083/jcb.202103178] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 11/12/2021] [Accepted: 12/10/2021] [Indexed: 01/07/2023] Open
Abstract
In selective autophagy of the nucleus (hereafter nucleophagy), nucleus-derived double-membrane vesicles (NDVs) are formed, sequestered within autophagosomes, and delivered to lysosomes or vacuoles for degradation. In Saccharomyces cerevisiae, the nuclear envelope (NE) protein Atg39 acts as a nucleophagy receptor, which interacts with Atg8 to target NDVs to the forming autophagosomal membranes. In this study, we revealed that Atg39 is anchored to the outer nuclear membrane via its transmembrane domain and also associated with the inner nuclear membrane via membrane-binding amphipathic helices (APHs) in its perinuclear space region, thereby linking these membranes. We also revealed that autophagosome formation-coupled Atg39 crowding causes the NE to protrude toward the cytoplasm, and the tips of the protrusions are pinched off to generate NDVs. The APHs of Atg39 are crucial for Atg39 crowding in the NE and subsequent NE protrusion. These findings suggest that the nucleophagy receptor Atg39 plays pivotal roles in NE deformation during the generation of NDVs to be degraded by nucleophagy.
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Affiliation(s)
- Keisuke Mochida
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Toshifumi Otani
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Yuto Katsumata
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Hiromi Kirisako
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Chika Kakuta
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Tetsuya Kotani
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Hitoshi Nakatogawa
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
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34
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Shankar R, Lettman MM, Whisler W, Frankel EB, Audhya A. The ESCRT machinery directs quality control over inner nuclear membrane architecture. Cell Rep 2022; 38:110263. [PMID: 35045304 PMCID: PMC8801257 DOI: 10.1016/j.celrep.2021.110263] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 11/21/2021] [Accepted: 12/21/2021] [Indexed: 11/20/2022] Open
Abstract
The late-acting endosomal sorting complex required for transport (ESCRT) machinery has been implicated in facilitating the resealing of the nuclear envelope (NE) after mitosis, enabling compartmentalization of the genome away from the cytoplasm. Here, we leverage the stereotypic first division of the C. elegans embryo to identify additional functions of the ESCRT machinery in maintaining the structure of the inner nuclear membrane. Specifically, impaired ESCRT function results in a defect in the pruning of inner nuclear membrane invaginations, which arise normally during NE reformation and expansion. Additionally, in combination with a hypomorphic mutation that interferes with assembly of the underlying nuclear lamina, inhibition of ESCRT function significantly perturbs NE architecture and increases chromosome segregation defects, resulting in penetrant embryonic lethality. Our findings highlight links between ESCRT-mediated inner nuclear membrane remodeling, maintenance of nuclear envelope morphology, and the preservation of the genome during early development. In this study, Shankar et al. demonstrate that defects in ESCRT machinery functions impair pruning of inner nuclear membrane invaginations that form normally after mitotic exit as the nuclear envelope undergoes expansion. These findings highlight a critical role for the ESCRT machinery in the maintenance of inner nuclear membrane morphology.
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Affiliation(s)
- Raakhee Shankar
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Molly M Lettman
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - William Whisler
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Elisa B Frankel
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA.
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35
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Lu MS, Drubin DG. Unexplored Cdc42 functions at the budding yeast nucleus suggested by subcellular localization. Small GTPases 2022; 13:255-266. [PMID: 34689711 PMCID: PMC9707532 DOI: 10.1080/21541248.2021.1993714] [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: 01/15/2023] Open
Abstract
In budding yeast, the Rho-family GTPase Cdc42 has several functions that depend on its subcellular localization and the cell cycle stage. During bud formation, Cdc42 localizes to the plasma membrane at the bud tip and bud neck where it carries out functions in actin polymerization, spindle positioning, and exocytosis to ensure proper polarity development. Recent live-cell imaging analysis revealed a novel localization of Cdc42 to a discrete intracellular focus associated with the vacuole and nuclear envelope. The discovery of this novel Cdc42 localization led to the identification of a new function in ESCRT-mediated nuclear envelope sealing. However, other aspects of this intracellular localization and its functional implications were not explored. Here, we further characterize the Cdc42 focus and present several novel observations that suggest possible additional Cdc42 functions at the nucleus, including nucleus-vacuole junction formation, nuclear envelope tethering, nuclear migration, and nucleopodia formation.
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Affiliation(s)
- Michelle S. Lu
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA,CONTACT Michelle S. Lu Department of Molecular and Cell Biology, University of California, 16 Barker Hall, Berkeley, California, 94720-3202, USA
| | - David G. Drubin
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
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36
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Agote-Arán A, Lin J, Sumara I. Fragile X–Related Protein 1 Regulates Nucleoporin Localization in a Cell Cycle–Dependent Manner. Front Cell Dev Biol 2021; 9:755847. [PMID: 34977012 PMCID: PMC8716781 DOI: 10.3389/fcell.2021.755847] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/10/2021] [Indexed: 11/17/2022] Open
Abstract
Nuclear pore complexes (NPCs) are embedded in the nuclear envelope (NE) where they ensure the transport of macromolecules between the nucleus and the cytoplasm. NPCs are built from nucleoporins (Nups) through a sequential assembly order taking place at two different stages during the cell cycle of mammalian cells: at the end of mitosis and during interphase. In addition, fragile X–related proteins (FXRPs) can interact with several cytoplasmic Nups and facilitate their localization to the NE during interphase likely through a microtubule-dependent mechanism. In the absence of FXRPs or microtubule-based transport, Nups aberrantly localize to the cytoplasm forming the so-called cytoplasmic nucleoporin granules (CNGs), compromising NPCs’ function on protein export. However, it remains unknown if Nup synthesis or degradation mechanisms are linked to the FXRP–Nup pathway and if and how the action of FXRPs on Nups is coordinated with the cell cycle progression. Here, we show that Nup localization defects observed in the absence of FXR1 are independent of active protein translation. CNGs are cleared in an autophagy- and proteasome-independent manner, and their presence is restricted to the early G1 phase of the cell cycle. Our results thus suggest that a pool of cytoplasmic Nups exists that contributes to the NPC assembly specifically during early G1 to ensure NPC homeostasis at a short transition from mitosis to the onset of interphase.
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Affiliation(s)
- Arantxa Agote-Arán
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Centre National de la Recherche Scientifique UMR 7104, Strasbourg, France
- Institut National de la Santé et de la Recherche Médicale U964, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - Junyan Lin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Centre National de la Recherche Scientifique UMR 7104, Strasbourg, France
- Institut National de la Santé et de la Recherche Médicale U964, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
| | - Izabela Sumara
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
- Centre National de la Recherche Scientifique UMR 7104, Strasbourg, France
- Institut National de la Santé et de la Recherche Médicale U964, Strasbourg, France
- Université de Strasbourg, Strasbourg, France
- *Correspondence: Izabela Sumara,
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37
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Chandra S, Mannino PJ, Thaller DJ, Ader NR, King MC, Melia TJ, Lusk CP. Atg39 selectively captures inner nuclear membrane into lumenal vesicles for delivery to the autophagosome. J Cell Biol 2021; 220:e202103030. [PMID: 34714326 PMCID: PMC8575018 DOI: 10.1083/jcb.202103030] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 08/26/2021] [Accepted: 09/29/2021] [Indexed: 12/26/2022] Open
Abstract
Mechanisms that turn over components of the nucleus and inner nuclear membrane (INM) remain to be fully defined. We explore how components of the INM are selected by a cytosolic autophagy apparatus through a transmembrane nuclear envelope-localized cargo adaptor, Atg39. A split-GFP reporter showed that Atg39 localizes to the outer nuclear membrane (ONM) and thus targets the INM across the nuclear envelope lumen. Consistent with this, sequence elements that confer both nuclear envelope localization and a membrane remodeling activity are mapped to the Atg39 lumenal domain; these lumenal motifs are required for the autophagy-mediated degradation of integral INM proteins. Interestingly, correlative light and electron microscopy shows that the overexpression of Atg39 leads to the expansion of the ONM and the enclosure of a network of INM-derived vesicles in the nuclear envelope lumen. Thus, we propose an outside-in model of nucleophagy where INM is delivered into vesicles in the nuclear envelope lumen, which can be targeted by the autophagosome.
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Affiliation(s)
| | | | | | | | | | - Thomas J. Melia
- Department of Cell Biology, Yale School of Medicine, New Haven, CT
| | - C. Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT
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38
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Nuclear pore complex maintenance and implications for age-related diseases. Trends Cell Biol 2021; 32:216-227. [PMID: 34782239 DOI: 10.1016/j.tcb.2021.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/04/2021] [Accepted: 10/07/2021] [Indexed: 12/31/2022]
Abstract
Nuclear pore complexes (NPCs) bridge the nucleus and the cytoplasm and are indispensable for crucial cellular activities, such as bidirectional molecular trafficking and gene transcription regulation. The discovery of long-lived proteins (LLPs) in NPCs from postmitotic cells raises the exciting possibility that the maintenance of NPC integrity might play an inherent role in lifelong cell function. Age-dependent deterioration of NPCs and loss of nuclear integrity have been linked to age-related decline in postmitotic cell function and degenerative diseases. In this review, we discuss our current understanding of NPC maintenance in proliferating and postmitotic cells, and how malfunction of nucleoporins (Nups) might contribute to the pathogenesis of various neurodegenerative and cardiovascular diseases.
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39
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Zhang W, Khan A, Vitale J, Neuner A, Rink K, Lüchtenborg C, Brügger B, Söllner TH, Schiebel E. A short perinuclear amphipathic α-helix in Apq12 promotes nuclear pore complex biogenesis. Open Biol 2021; 11:210250. [PMID: 34814743 PMCID: PMC8611336 DOI: 10.1098/rsob.210250] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The integral membrane protein Apq12 is an important nuclear envelope (NE)/endoplasmic reticulum (ER) modulator that cooperates with the nuclear pore complex (NPC) biogenesis factors Brl1 and Brr6. How Apq12 executes these functions is unknown. Here, we identified a short amphipathic α-helix (AαH) in Apq12 that links the two transmembrane domains in the perinuclear space and has liposome-binding properties. Cells expressing an APQ12 (apq12-ah) version in which AαH is disrupted show NPC biogenesis and NE integrity defects, without impacting Apq12-ah topology or NE/ER localization. Overexpression of APQ12 but not apq12-ah triggers striking over-proliferation of the outer nuclear membrane (ONM)/ER and promotes accumulation of phosphatidic acid (PA) at the NE. Apq12 and Apq12-ah both associate with NPC biogenesis intermediates and removal of AαH increases both Brl1 levels and the interaction between Brl1 and Brr6. We conclude that the short amphipathic α-helix of Apq12 regulates the function of Brl1 and Brr6 and promotes PA accumulation at the NE possibly during NPC biogenesis.
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Affiliation(s)
- Wanlu Zhang
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Azqa Khan
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Jlenia Vitale
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Annett Neuner
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Kerstin Rink
- Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany
| | - Christian Lüchtenborg
- Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany
| | - Britta Brügger
- Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany
| | - Thomas H. Söllner
- Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany
| | - Elmar Schiebel
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
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40
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Pawar S, Kutay U. The Diverse Cellular Functions of Inner Nuclear Membrane Proteins. Cold Spring Harb Perspect Biol 2021; 13:a040477. [PMID: 33753404 PMCID: PMC8411953 DOI: 10.1101/cshperspect.a040477] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The nuclear compartment is delimited by a specialized expanded sheet of the endoplasmic reticulum (ER) known as the nuclear envelope (NE). Compared to the outer nuclear membrane and the contiguous peripheral ER, the inner nuclear membrane (INM) houses a unique set of transmembrane proteins that serve a staggering range of functions. Many of these functions reflect the exceptional position of INM proteins at the membrane-chromatin interface. Recent research revealed that numerous INM proteins perform crucial roles in chromatin organization, regulation of gene expression, genome stability, and mediation of signaling pathways into the nucleus. Other INM proteins establish mechanical links between chromatin and the cytoskeleton, help NE remodeling, or contribute to the surveillance of NE integrity and homeostasis. As INM proteins continue to gain prominence, we review these advancements and give an overview on the functional versatility of the INM proteome.
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Affiliation(s)
- Sumit Pawar
- Institute of Biochemistry, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Ulrike Kutay
- Institute of Biochemistry, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
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41
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Coyne AN, Baskerville V, Zaepfel BL, Dickson DW, Rigo F, Bennett F, Lusk CP, Rothstein JD. Nuclear accumulation of CHMP7 initiates nuclear pore complex injury and subsequent TDP-43 dysfunction in sporadic and familial ALS. Sci Transl Med 2021; 13:eabe1923. [PMID: 34321318 PMCID: PMC9022198 DOI: 10.1126/scitranslmed.abe1923] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 03/02/2021] [Accepted: 06/09/2021] [Indexed: 01/29/2023]
Abstract
Alterations in the components [nucleoporins (Nups)] and function of the nuclear pore complex (NPC) have been implicated as contributors to the pathogenesis of genetic forms of neurodegeneration including C9orf72 amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD). We hypothesized that Nup alterations and the consequential loss of NPC function may lie upstream of TDP-43 dysfunction and mislocalization widely observed in ALS, FTD, and related neurodegenerative diseases. Here, we provide evidence that CHMP7, a critical mediator of NPC quality control, is increased in nuclei of C9orf72 and sporadic ALS induced pluripotent stem cell (iPSC)-derived spinal neurons (iPSNs) and postmortem human motor cortex before the emergence of Nup alterations. Inhibiting the nuclear export of CHMP7 triggered Nup reduction and TDP-43 dysfunction and pathology in human neurons. Knockdown of CHMP7 alleviated disease-associated Nup alterations, deficits in Ran GTPase localization, defects in TDP-43-associated mRNA expression, and downstream glutamate-induced neuronal death. Thus, our data support a role for altered CHMP7-mediated Nup homeostasis as a prominent initiating pathological mechanism for familial and sporadic ALS and highlight the potential for CHMP7 as therapeutic target.
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Affiliation(s)
- Alyssa N Coyne
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Victoria Baskerville
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Benjamin L Zaepfel
- Biochemistry, Cellular, and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA 92010, USA
| | | | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Jeffrey D Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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42
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Gatta AT, Olmos Y, Stoten CL, Chen Q, Rosenthal PB, Carlton JG. CDK1 controls CHMP7-dependent nuclear envelope reformation. eLife 2021; 10:59999. [PMID: 34286694 PMCID: PMC8324300 DOI: 10.7554/elife.59999] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 07/09/2021] [Indexed: 12/21/2022] Open
Abstract
Through membrane sealing and disassembly of spindle microtubules, the Endosomal Sorting Complex Required for Transport-III (ESCRT-III) machinery has emerged as a key player in the regeneration of a sealed nuclear envelope (NE) during mitotic exit, and in the repair of this organelle during interphase rupture. ESCRT-III assembly at the NE occurs transiently during mitotic (M) exit and is initiated when CHMP7, an ER-localised ESCRT-II/ESCRT-III hybrid protein, interacts with the Inner Nuclear Membrane (INM) protein LEM2. Whilst classical nucleocytoplasmic transport mechanisms have been proposed to separate LEM2 and CHMP7 during interphase, it is unclear how CHMP7 assembly is suppressed in mitosis when NE and ER identities are mixed. Here, we use live cell imaging and protein biochemistry to examine the biology of these proteins during M-exit. Firstly, we show that CHMP7 plays an important role in the dissolution of LEM2 clusters that form at the NE during M-exit. Secondly, we show that CDK1 phosphorylates CHMP7 upon M-entry at Ser3 and Ser441 and that this phosphorylation reduces CHMP7's interaction with LEM2, limiting its assembly during M-phase. We show that spatiotemporal differences in the dephosphorylation of CHMP7 license its assembly at the NE during telophase, but restrict its assembly on the ER at this time. Without CDK1 phosphorylation, CHMP7 undergoes inappropriate assembly in the peripheral ER during M-exit, capturing LEM2 and downstream ESCRT-III components. Lastly, we establish that a microtubule network is dispensable for ESCRT-III assembly at the reforming nuclear envelope. These data identify a key cell-cycle control programme allowing ESCRT-III-dependent nuclear regeneration.
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Affiliation(s)
- Alberto T Gatta
- School of Cancer and Pharmaceutical Sciences, King's College, London, United Kingdom.,Organelle Dynamics Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Yolanda Olmos
- School of Cancer and Pharmaceutical Sciences, King's College, London, United Kingdom.,Organelle Dynamics Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Caroline L Stoten
- School of Cancer and Pharmaceutical Sciences, King's College, London, United Kingdom.,Organelle Dynamics Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Qu Chen
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Peter B Rosenthal
- Structural Biology of Cells and Viruses Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Jeremy G Carlton
- School of Cancer and Pharmaceutical Sciences, King's College, London, United Kingdom.,Organelle Dynamics Laboratory, The Francis Crick Institute, London, United Kingdom
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43
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Coyne AN, Rothstein JD. The ESCRT-III protein VPS4, but not CHMP4B or CHMP2B, is pathologically increased in familial and sporadic ALS neuronal nuclei. Acta Neuropathol Commun 2021; 9:127. [PMID: 34281622 PMCID: PMC8287756 DOI: 10.1186/s40478-021-01228-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 07/12/2021] [Indexed: 12/11/2022] Open
Abstract
Nuclear pore complex injury has recently emerged as an early and significant contributor to familial and sporadic ALS disease pathogenesis. However, the molecular events leading to this pathological phenomenon characterized by the reduction of specific nucleoporins from neuronal nuclear pore complexes remain largely unknown. This is due in part to a lack of knowledge regarding the biological pathways and proteins underlying nuclear pore complex homeostasis specifically in human neurons. We have recently uncovered that aberrant nuclear accumulation of the ESCRT-III protein CHMP7 initiates nuclear pore complex in familial and sporadic ALS neurons. In yeast and non-neuronal mammalian cells, nuclear relocalization of CHMP7 has been shown to recruit the ESCRT-III proteins CHMP4B, CHMP2B, and VPS4 to facilitate nuclear pore complex and nuclear envelope repair and homeostasis. Here, using super resolution structured illumination microscopy, we find that neither CHMP4B nor CHMP2B are increased in ALS neuronal nuclei. In contrast, VPS4 expression is significantly increased in ALS neuronal nuclei prior to the emergence of nuclear pore injury in a CHMP7 dependent manner. However, unlike our prior CHMP7 knockdown studies, impaired VPS4 function does not mitigate alterations to the NPC and the integral transmembrane nucleoporin POM121. Collectively our data suggest that while alterations in VPS4 subcellular localization appear to be coincident with nuclear pore complex injury, therapeutic efforts to mitigate this pathogenic cascade should be targeted towards upstream events such as the nuclear accumulation of CHMP7 as we have previously described.
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Affiliation(s)
- Alyssa N. Coyne
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205 USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205 USA
| | - Jeffrey D. Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205 USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205 USA
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44
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Abstract
Membrane-bound organelles provide physical and functional compartmentalization of biological processes in eukaryotic cells. The characteristic shape and internal organization of these organelles is determined by a combination of multiple internal and external factors. The maintenance of the shape of nucleus, which houses the genetic material within a double membrane bilayer, is crucial for a seamless spatio-temporal control over nuclear and cellular functions. Dynamic morphological changes in the shape of nucleus facilitate various biological processes. Chromatin packaging, nuclear and cytosolic protein organization, and nuclear membrane lipid homeostasis are critical determinants of overall nuclear morphology. As such, a multitude of molecular players and pathways act together to regulate the nuclear shape. Here, we review the known mechanisms governing nuclear shape in various unicellular and multicellular organisms, including the non-spherical nuclei and non-lamin-related structural determinants. The review also touches upon cellular consequences of aberrant nuclear morphologies.
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Affiliation(s)
- Pallavi Deolal
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Krishnaveni Mishra
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
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45
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Tseng CC, Dean S, Davies BA, Azmi IF, Pashkova N, Payne JA, Staffenhagen J, West M, Piper RC, Odorizzi G, Katzmann DJ. Bro1 stimulates Vps4 to promote intralumenal vesicle formation during multivesicular body biogenesis. J Cell Biol 2021; 220:212434. [PMID: 34160559 PMCID: PMC8240856 DOI: 10.1083/jcb.202102070] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 05/18/2021] [Accepted: 05/23/2021] [Indexed: 01/20/2023] Open
Abstract
Endosomal sorting complexes required for transport (ESCRT-0, -I, -II, -III) execute cargo sorting and intralumenal vesicle (ILV) formation during conversion of endosomes to multivesicular bodies (MVBs). The AAA-ATPase Vps4 regulates the ESCRT-III polymer to facilitate membrane remodeling and ILV scission during MVB biogenesis. Here, we show that the conserved V domain of ESCRT-associated protein Bro1 (the yeast homologue of mammalian proteins ALIX and HD-PTP) directly stimulates Vps4. This activity is required for MVB cargo sorting. Furthermore, the Bro1 V domain alone supports Vps4/ESCRT–driven ILV formation in vivo without efficient MVB cargo sorting. These results reveal a novel activity of the V domains of Bro1 homologues in licensing ESCRT-III–dependent ILV formation and suggest a role in coordinating cargo sorting with membrane remodeling during MVB sorting. Moreover, ubiquitin binding enhances V domain stimulation of Vps4 to promote ILV formation via the Bro1–Vps4–ESCRT-III axis, uncovering a novel role for ubiquitin during MVB biogenesis in addition to facilitating cargo recognition.
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Affiliation(s)
- Chun-Che Tseng
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN.,Biochemistry and Molecular Biology Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN
| | - Shirley Dean
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN.,Biochemistry and Molecular Biology Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN
| | - Brian A Davies
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Ishara F Azmi
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN.,Biochemistry and Molecular Biology Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN
| | - Natalya Pashkova
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Johanna A Payne
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | | | - Matt West
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO
| | - Robert C Piper
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Greg Odorizzi
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO
| | - David J Katzmann
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN.,Biochemistry and Molecular Biology Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN
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46
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Wu Z, Xu H, Liu J, Zhou F, Liang Y. The ESCRT-III complex contributes to macromitophagy in yeast. Traffic 2021; 22:258-273. [PMID: 34089296 DOI: 10.1111/tra.12805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 05/29/2021] [Accepted: 05/31/2021] [Indexed: 12/19/2022]
Abstract
Mitochondria play important roles in energy generation and homeostasis maintenance in eukaryotic cells. The damaged or superfluous mitochondria can be nonselectively or selectively removed through the autophagy/lysosome pathway, which was referred as mitophagy. According to the molecular machinery for degrading mitochondria, the selectively removed mitochondria can occur through macromitophagy or micromitophagy. In this study, we show that the endosomal sorting complex required for transport III (ESCRT-III) in budding yeast regulates macromitophagy induced by nitrogen starvation, but not by the post-logarithmic phase growth in lactate medium by monitoring a mitochondrial marker, Om45. Firstly, loss of ESCRT-III subunit Snf7 or Vps4-Vta1 complex subunit Vps4, two representative subunits of the ESCRT complex, suppresses the delivery and degradation of Om45-GFP to vacuoles. Secondly, we show that the mitochondrial marker Om45 and mitophagy receptor Atg32 accumulate on autophagosomes marked with Atg8 (mitophagosomes, MPs) in ESCRT mutants. Moreover, the protease-protection assay indicates that Snf7 and Vps4 are involved in MP closure. Finally, Snf7 interacts with Atg11, which was detected by two ways, glutathione-S-transferase (GST) pulldown and bimolecular fluorescence complementation (BiFC) assay, and this BiFC interaction happens on mitochondrial reticulum. Therefore, we proposed that the ESCRT-III machinery mediates nitrogen starvation-induced macromitophagy by the interaction between Snf7 and Atg11 so that Snf7 is recruited to Atg32-marked MPs by the known Atg11-Atg32 interaction to seal them. These results reveal that the ESCRT-III complex plays a new role in yeast on macromitophagy.
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Affiliation(s)
- Zulin Wu
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
| | - Haiqian Xu
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
| | - Junze Liu
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
| | - Fan Zhou
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
| | - Yongheng Liang
- College of Life Sciences, Key Laboratory of Agricultural Environmental Microbiology of Ministry of Agriculture and Rural Affairs, Nanjing Agricultural University, Nanjing, China
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47
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Abstract
The nuclear envelope (NE) is continuous with the endoplasmic reticulum (ER), yet the NE carries out many functions distinct from those of bulk ER. This functional specialization depends on a unique protein composition that defines NE identity and must be both established and actively maintained. The NE undergoes extensive remodeling in interphase and mitosis, so mechanisms that seal NE holes and protect its unique composition are critical for maintaining its functions. New evidence shows that closure of NE holes relies on regulated de novo lipid synthesis, providing a link between lipid metabolism and generating and maintaining NE identity. Here, we review regulation of the lipid bilayers of the NE and suggest ways to generate lipid asymmetry across the NE despite its direct continuity with the ER. We also discuss the elusive mechanism of membrane fusion during nuclear pore complex (NPC) biogenesis. We propose a model in which NPC biogenesis is carefully controlled to ensure that a permeability barrier has been established before membrane fusion, thereby avoiding a major threat to compartmentalization.
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Affiliation(s)
- Shirin Bahmanyar
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06520
| | - Christian Schlieker
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT 06520.,Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
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48
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Koch BA, Staley E, Jin H, Yu HG. The ESCRT-III complex is required for nuclear pore complex sequestration and regulates gamete replicative lifespan in budding yeast meiosis. Nucleus 2021; 11:219-236. [PMID: 32893723 PMCID: PMC7529410 DOI: 10.1080/19491034.2020.1812872] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cellular aging occurs as a cell loses its ability to maintain homeostasis. Aging cells eliminate damaged cellular compartments and other senescence factors via self-renewal. The mechanism that regulates cellular rejuvenation remains to be further elucidated. Using budding yeast gametogenesis as a model, we show here that the endosomal sorting complex required for transport (ESCRT) III regulates nuclear envelope organization. During gametogenesis, the nuclear pore complex (NPC) and other senescence factors are sequestered away from the prospore nuclei. We show that the LEM-domain protein Heh1 (Src1) facilitates the nuclear recruitment of ESCRT-III, which is required for meiotic NPC sequestration and nuclear envelope remodeling. Furthermore, ESCRT-III-mediated nuclear reorganization appears to be critical for gamete rejuvenation, as hindering this process curtails either directly or indirectly the replicative lifespan in gametes. Our findings demonstrate the importance of ESCRT-III in nuclear envelope remodeling and its potential role in eliminating senescence factors during gametogenesis.
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Affiliation(s)
- Bailey A Koch
- Department of Biological Science, The Florida State University , Tallahassee, FL, USA
| | - Elizabeth Staley
- Department of Biological Science, The Florida State University , Tallahassee, FL, USA
| | - Hui Jin
- Department of Biological Science, The Florida State University , Tallahassee, FL, USA
| | - Hong-Guo Yu
- Department of Biological Science, The Florida State University , Tallahassee, FL, USA
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49
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Host and Viral Factors Involved in Nuclear Egress of Herpes Simplex Virus 1. Viruses 2021; 13:v13050754. [PMID: 33923040 PMCID: PMC8146395 DOI: 10.3390/v13050754] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/20/2021] [Accepted: 04/23/2021] [Indexed: 12/14/2022] Open
Abstract
Herpes simplex virus 1 (HSV-1) replicates its genome and packages it into capsids within the nucleus. HSV-1 has evolved a complex mechanism of nuclear egress whereby nascent capsids bud on the inner nuclear membrane to form perinuclear virions that subsequently fuse with the outer nuclear membrane, releasing capsids into the cytosol. The viral-encoded nuclear egress complex (NEC) plays a crucial role in this vesicle-mediated nucleocytoplasmic transport. Nevertheless, similar system mediates the movement of other cellular macromolecular complexes in normal cells. Therefore, HSV-1 may utilize viral proteins to hijack the cellular machinery in order to facilitate capsid transport. However, little is known about the molecular mechanisms underlying this phenomenon. This review summarizes our current understanding of the cellular and viral factors involved in the nuclear egress of HSV-1 capsids.
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50
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Deolal P, Male G, Mishra K. The challenge of staying in shape: nuclear size matters. Curr Genet 2021; 67:605-612. [PMID: 33779777 DOI: 10.1007/s00294-021-01176-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 03/06/2021] [Accepted: 03/08/2021] [Indexed: 10/21/2022]
Abstract
Cellular organelles have unique morphology and the organelle size to cell size ratio is regulated. Nucleus is one of the most prominent, usually round in shape, organelle of a eukaryotic cell that occupies 8-10% of cellular volume. The shape and size of nucleus is known to undergo remodeling during processes such as cell growth, division and certain stresses. Regulation of protein and lipid distribution at the nuclear envelope is crucial for preserving the nuclear morphology and size. As size and morphology are interlinked, altering one influences the other. In this perspective, we discuss the relationship between size and shape regulation of the nucleus.
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Affiliation(s)
- Pallavi Deolal
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Gurranna Male
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Krishnaveni Mishra
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India.
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