1
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Lim K, Hazawa M, Wong RW. Crafty mimicry grants nuclear pore entry to HIV. Cell Host Microbe 2024; 32:441-442. [PMID: 38604120 DOI: 10.1016/j.chom.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 03/08/2024] [Indexed: 04/13/2024]
Abstract
The size of the nuclear pore should, in principle, prevent HIV-1 entry. However, HIV-1 capsid is able to gain nuclear pore entry. In a recent issue of Nature, Fu et al. and Dickson et al. demonstrate that the HIV-1 capsid mimics the nuclear transport protein karyopherins to access host nuclei.
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Affiliation(s)
- Keesiang Lim
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan
| | - Masaharu Hazawa
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan; Cell-Bionomics Research Unit, Innovative Integrated Bio-Research Core, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan
| | - Richard W Wong
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan; Cell-Bionomics Research Unit, Innovative Integrated Bio-Research Core, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan.
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2
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Stefanello ST, Mizdal CR, Shahin V. Pitstop-2 Upsets The Integrity of Nuclear Pore Complexes (NPCs) by Interaction with β-Propeller Folds of Npc Scaffold Proteins. Adv Biol (Weinh) 2024; 8:e2300360. [PMID: 38129324 DOI: 10.1002/adbi.202300360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 11/22/2023] [Indexed: 12/23/2023]
Abstract
The small compound Pitstop-2 is a recent potent inhibitor of clathrin-mediated endocytosis (CME), widely used in biomedical research areas. In recent years, however, it is observed that it exhibits CME-independent inhibitory effects on nuclear pore complexes (NPCs), the nucleocytoplasmic gatekeepers. NPCs are elaborate proteinaceous transport nano-machineries of crucial physiological importance rendering them novel targets for various medical applications. They mediate all nucleocytoplasmic transport forming a physiologically essential selective nucleocytoplasmic barrier. The direct Pitstop-2 disruptive effects on NPCs manifested themselves at both the structural and functional integrity levels. Moreover, they are massive, acute, and detectable at concentrations equal to CME-inhibitory concentrations. Pitstop-2 inhibits CME by binding to the terminal β-propeller domain of the heavy chain of clathrin. Several NPC scaffold proteins, critical for the structural and functional integrity of the NPC, possess β-propeller folds. Herein, utilizing computational docking analysis, it is demonstrated that Pitstop-2 exhibits particularly high binding affinities to β-propeller folds of NPC scaffold proteins, similar to its binding affinity to the terminal β-propeller domain of clathrin. The authors, therefore, conclude that Pitstop-2 is a potent disruptor of NPCs, an activity which, separately or in synergy with CME inhibition, may be exploited for a myriad of pharmacological applications.
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Affiliation(s)
- Sílvio Terra Stefanello
- Institute of Physiology II, University of Münster, Robert-Koch-Str. 27b, 48149, Münster, Germany
| | - Caren Rigon Mizdal
- Institute of Physiology II, University of Münster, Robert-Koch-Str. 27b, 48149, Münster, Germany
| | - Victor Shahin
- Institute of Physiology II, University of Münster, Robert-Koch-Str. 27b, 48149, Münster, Germany
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3
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Klughammer N, Barth A, Dekker M, Fragasso A, Onck PR, Dekker C. Diameter dependence of transport through nuclear pore complex mimics studied using optical nanopores. eLife 2024; 12:RP87174. [PMID: 38376900 PMCID: PMC10942607 DOI: 10.7554/elife.87174] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2024] Open
Abstract
The nuclear pore complex (NPC) regulates the selective transport of large biomolecules through the nuclear envelope. As a model system for nuclear transport, we construct NPC mimics by functionalizing the pore walls of freestanding palladium zero-mode waveguides with the FG-nucleoporin Nsp1. This approach enables the measurement of single-molecule translocations through individual pores using optical detection. We probe the selectivity of Nsp1-coated pores by quantitatively comparing the translocation rates of the nuclear transport receptor Kap95 to the inert probe BSA over a wide range of pore sizes from 35 nm to 160 nm. Pores below 55 ± 5 nm show significant selectivity that gradually decreases for larger pores. This finding is corroborated by coarse-grained molecular dynamics simulations of the Nsp1 mesh within the pore, which suggest that leakage of BSA occurs by diffusion through transient openings within the dynamic mesh. Furthermore, we experimentally observe a modulation of the BSA permeation when varying the concentration of Kap95. The results demonstrate the potential of single-molecule fluorescence measurements on biomimetic NPCs to elucidate the principles of nuclear transport.
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Affiliation(s)
- Nils Klughammer
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of TechnologyDelftNetherlands
| | - Anders Barth
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of TechnologyDelftNetherlands
| | - Maurice Dekker
- Zernike Institute for Advanced Materials, University of GroningenGroningenNetherlands
| | - Alessio Fragasso
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of TechnologyDelftNetherlands
| | - Patrick R Onck
- Zernike Institute for Advanced Materials, University of GroningenGroningenNetherlands
| | - Cees Dekker
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of TechnologyDelftNetherlands
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4
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Yoo TY, Mitchison TJ. Quantitative comparison of nuclear transport inhibition by SARS coronavirus ORF6 reveals the importance of oligomerization. Proc Natl Acad Sci U S A 2024; 121:e2307997121. [PMID: 38236733 PMCID: PMC10823255 DOI: 10.1073/pnas.2307997121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 12/02/2023] [Indexed: 01/23/2024] Open
Abstract
Open Reading Frame 6 (ORF6) proteins, which are unique to severe acute respiratory syndrome-related (SARS) coronavirus, inhibit the classical nuclear import pathway to antagonize host antiviral responses. Several alternative models were proposed to explain the inhibitory function of ORF6 [H. Xia et al., Cell Rep. 33, 108234 (2020); L. Miorin et al., Proc. Natl. Acad. Sci. U.S.A. 117, 28344-28354 (2020); and M. Frieman et al., J. Virol. 81, 9812-9824 (2007)]. To distinguish these models and build quantitative understanding of ORF6 function, we developed a method for scoring both ORF6 concentration and functional effect in single living cells. We combined quantification of untagged ORF6 expression level in single cells with optogenetics-based measurement of nuclear transport kinetics, using methods that could be adapted to measure concentration-dependent effects of any untagged protein. We found that SARS-CoV-2 ORF6 is ~15 times more potent than SARS-CoV-1 ORF6 in inhibiting nuclear import and export, due to differences in the C-terminal region that is required for the NUP98-RAE1 binding. The N-terminal region was required for transport inhibition. This region binds membranes but could be replaced by synthetic constructs which forced oligomerization in solution, suggesting its primary function is oligomerization. We propose that the hydrophobic N-terminal region drives oligomerization of ORF6 to multivalently cross-link the NUP98-RAE1 complexes at the nuclear pore complex, and this multivalent binding inhibits bidirectional transport.
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Affiliation(s)
- Tae Yeon Yoo
- Department of Systems Biology, Blavatnik Institute, Harvard Medical School, Boston, MA02115
| | - Timothy J. Mitchison
- Department of Systems Biology, Blavatnik Institute, Harvard Medical School, Boston, MA02115
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5
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Siegel J, Grossberger D, Pryjmaková J, Šlouf M, Malinský P, Ceccio G, Vacík J. Modification of AgNP-Decorated PET: A Promising Strategy for Preparation of AgNP-Filled Nuclear Pores in Polymer Membranes. Int J Mol Sci 2024; 25:712. [PMID: 38255786 PMCID: PMC10815600 DOI: 10.3390/ijms25020712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 01/24/2024] Open
Abstract
Polymer-based membranes represent an irreplaceable group of materials that can be applied in a wide range of key industrial areas, from packaging to high-end technologies. Increased selectivity to transport properties or the possibility of controlling membrane permeability by external stimuli represents a key issue in current material research. In this work, we present an unconventional approach with the introduction of silver nanoparticles (AgNPs) into membrane pores, by immobilising them onto the surface of polyethyleneterephthalate (PET) foil with subsequent physical modification by means of laser and plasma radiation prior to membrane preparation. Our results showed that the surface characteristics of AgNP-decorated PET (surface morphology, AgNP content, and depth profile) affected the distribution and concentration of AgNPs in subsequent ion-track membranes. We believe that the presented approach affecting the redistribution of AgNPs in the polymer volume may open up new possibilities for the preparation of metal nanoparticle-filled polymeric membranes. The presence of AgNPs on the pore walls can facilitate the grafting of stimuli-responsive molecules onto these active sites and may contribute to the development of intelligent membranes with controllable transport properties.
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Affiliation(s)
- Jakub Siegel
- Department of Solid State Engineering, University of Chemistry and Technology Prague, 166 28 Prague, Czech Republic; (D.G.); (J.P.)
| | - Daniel Grossberger
- Department of Solid State Engineering, University of Chemistry and Technology Prague, 166 28 Prague, Czech Republic; (D.G.); (J.P.)
| | - Jana Pryjmaková
- Department of Solid State Engineering, University of Chemistry and Technology Prague, 166 28 Prague, Czech Republic; (D.G.); (J.P.)
| | - Miroslav Šlouf
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovského nám. 2, 162 06 Prague, Czech Republic;
| | - Petr Malinský
- Department of Physics, Faculty of Science, University of Jan Evangelista Purkyně in Ústí nad Labem, 400 03 Usti nad Labem, Czech Republic;
- Department of Neutron Physics, Nuclear Physics Institute of the Czech Academy of Sciences, 250 68 Husinec, Czech Republic; (G.C.); (J.V.)
| | - Giovanni Ceccio
- Department of Neutron Physics, Nuclear Physics Institute of the Czech Academy of Sciences, 250 68 Husinec, Czech Republic; (G.C.); (J.V.)
| | - Jiří Vacík
- Department of Neutron Physics, Nuclear Physics Institute of the Czech Academy of Sciences, 250 68 Husinec, Czech Republic; (G.C.); (J.V.)
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6
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Höhne P, Bohnert M. Hard to handle: how lipid saturation affects the nuclear envelope. Trends Cell Biol 2024; 34:1-2. [PMID: 37949805 DOI: 10.1016/j.tcb.2023.10.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 10/24/2023] [Indexed: 11/12/2023]
Abstract
The nuclear envelope is a unique subdomain of the endoplasmic reticulum (ER) that encapsulates the genome and mediates communication between the nucleus and the rest of the cell via nuclear pore complexes. A recent study by Romanauska and Köhler shows that balanced lipid unsaturation is critical for nuclear envelope and nuclear pore complex architecture and function.
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Affiliation(s)
- Pascal Höhne
- Institute of Cell Dynamics and Imaging, University of Münster, Münster, Germany
| | - Maria Bohnert
- Institute of Cell Dynamics and Imaging, University of Münster, Münster, Germany; Cells in Motion Interfaculty Centre, University of Münster, Münster, Germany.
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7
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Li Y, Bertozzi A, Mann MRW, Kühn B. Interdependent changes of nuclear lamins, nuclear pore complexes, and ploidy regulate cellular regeneration and stress response in the heart. Nucleus 2023; 14:2246310. [PMID: 37606283 PMCID: PMC10446781 DOI: 10.1080/19491034.2023.2246310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 07/28/2023] [Accepted: 08/04/2023] [Indexed: 08/23/2023] Open
Abstract
In adult mammals, many heart muscle cells (cardiomyocytes) are polyploid, do not proliferate (post-mitotic), and, consequently, cannot contribute to heart regeneration. In contrast, fetal and neonatal heart muscle cells are diploid, proliferate, and contribute to heart regeneration. We have identified interdependent changes of the nuclear lamina, nuclear pore complexes, and DNA-content (ploidy) in heart muscle cell maturation. These results offer new perspectives on how cells alter their nuclear transport and, with that, their gene regulation in response to extracellular signals. We present how changes of the nuclear lamina alter nuclear pore complexes in heart muscle cells. The consequences of these changes for cellular regeneration and stress response in the heart are discussed.
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Affiliation(s)
- Yao Li
- Division of Pediatric Cardiology, Pediatric Institute for Heart Regeneration and Therapeutics (I-HRT), UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA, USA
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Alberto Bertozzi
- Division of Pediatric Cardiology, Pediatric Institute for Heart Regeneration and Therapeutics (I-HRT), UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA, USA
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Mellissa RW Mann
- Department of Obstetrics, Gynaecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Magee-Womens Research Institute, Pittsburgh, PA, USA
| | - Bernhard Kühn
- Division of Pediatric Cardiology, Pediatric Institute for Heart Regeneration and Therapeutics (I-HRT), UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA, USA
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- McGowan Institute of Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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8
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Fahrenkrog B, Gasser SM. Structure and function of the nuclear envelope and nuclear pores. FEBS Lett 2023; 597:2703-2704. [PMID: 38013590 DOI: 10.1002/1873-3468.14769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Affiliation(s)
- Birthe Fahrenkrog
- Biozentrum, University of Basel, Spitalstrasse 41, Basel, 4056, Switzerland
| | - Susan M Gasser
- Department of Fundamental Microbiology, University of Lausanne, Switzerland
- ISREC Foundation, Agora Cancer Research Center, Rue du Bugnon 25A, Lausanne, 1005, Switzerland
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9
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Shevelyov YY. Interactions of Chromatin with the Nuclear Lamina and Nuclear Pore Complexes. Int J Mol Sci 2023; 24:15771. [PMID: 37958755 PMCID: PMC10649103 DOI: 10.3390/ijms242115771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 10/26/2023] [Accepted: 10/29/2023] [Indexed: 11/15/2023] Open
Abstract
Heterochromatin and euchromatin form different spatial compartments in the interphase nucleus, with heterochromatin being localized mainly at the nuclear periphery. The mechanisms responsible for peripheral localization of heterochromatin are still not fully understood. The nuclear lamina and nuclear pore complexes were obvious candidates for the role of heterochromatin binders. This review is focused on recent studies showing that heterochromatin interactions with the nuclear lamina and nuclear pore complexes maintain its peripheral localization. Differences in chromatin interactions with the nuclear envelope in cell populations and in individual cells are also discussed.
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Affiliation(s)
- Yuri Y Shevelyov
- Laboratory of Analysis of Gene Regulation, National Research Centre "Kurchatov Institute", Kurchatov Sq. 2, 123182 Moscow, Russia
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10
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Döhner K, Serrero MC, Sodeik B. The role of nuclear pores and importins for herpes simplex virus infection. Curr Opin Virol 2023; 62:101361. [PMID: 37672874 DOI: 10.1016/j.coviro.2023.101361] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 07/31/2023] [Accepted: 08/08/2023] [Indexed: 09/08/2023]
Abstract
Microtubule transport and nuclear import are functionally connected, and the nuclear pore complex (NPC) can interact with microtubule motors. For several alphaherpesvirus proteins, nuclear localization signals (NLSs) and their interactions with specific importin-α proteins have been characterized. Here, we review recent insights on the roles of microtubule motors, capsid-associated NLSs, and importin-α proteins for capsid transport, capsid docking to NPCs, and genome release into the nucleoplasm, as well as the role of importins for nuclear viral transcription, replication, capsid assembly, genome packaging, and nuclear capsid egress. Moreover, importin-α proteins exert antiviral effects by promoting the nuclear import of transcription factors inducing the expression of interferons (IFN), cytokines, and IFN-stimulated genes, and the IFN-inducible MxB restricts capsid docking to NPCs.
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Affiliation(s)
- Katinka Döhner
- Institute of Virology, Hannover Medical School, Hannover, Germany; Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany; RESIST - Cluster of Excellence, Hannover Medical School, Hannover, Germany.
| | - Manutea C Serrero
- Institute of Virology, Hannover Medical School, Hannover, Germany; RESIST - Cluster of Excellence, Hannover Medical School, Hannover, Germany
| | - Beate Sodeik
- Institute of Virology, Hannover Medical School, Hannover, Germany; RESIST - Cluster of Excellence, Hannover Medical School, Hannover, Germany; DZIF - German Centre for Infection Research, Braunschweig, Hannover, Germany.
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11
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Nobari P, Doye V, Boumendil C. Metazoan nuclear pore complexes in gene regulation and genome stability. DNA Repair (Amst) 2023; 130:103565. [PMID: 37696111 DOI: 10.1016/j.dnarep.2023.103565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 08/28/2023] [Accepted: 08/28/2023] [Indexed: 09/13/2023]
Abstract
The nuclear pore complexes (NPCs), one of the hallmarks of eukaryotic nuclei, allow selective transport of macromolecules between the cytoplasm and the nucleus. Besides this canonical function, an increasing number of additional roles have been attributed to the NPCs and their constituents, the nucleoporins. Here we review recent insights into the mechanisms by which NPCs and nucleoporins affect transcription and DNA repair in metazoans. In the first part, we discuss how gene expression can be affected by the localization of genome-nucleoporin interactions at pores or "off-pores", by the role of nucleoporins in chromatin organization at different scales, or by the physical properties of nucleoporins. In the second part, we review the contribution of NPCs to genome stability, including transport-dependent and -independent functions and the role of positioning at NPCs in the repair of heterochromatic breaks and the regulation of replication stress.
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Affiliation(s)
- Parisa Nobari
- IGH, Université de Montpellier, CNRS, Montpellier, France
| | - Valérie Doye
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
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12
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Schenkel L, Wang X, Le N, Burger M, Kroschewski R. A dedicated cytoplasmic container collects extrachromosomal DNA away from the mammalian nucleus. Mol Biol Cell 2023; 34:ar105. [PMID: 37556227 PMCID: PMC10559310 DOI: 10.1091/mbc.e23-04-0118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/27/2023] [Accepted: 07/31/2023] [Indexed: 08/11/2023] Open
Abstract
Expression from transfected plasmid DNA is generally transient, but it is unclear what process terminates it. We show that DNA entering mammalian cells is rapidly surrounded by a double membrane in the cytoplasm, in some cases after leaving the nucleus. This cytoplasmic container, termed exclusome, frequently also contains extrachromosomal telomeric DNA, and is maintained by the cell over several division cycles. The exclusome envelope contains endoplasmic reticulum proteins and the inner-nuclear membrane proteins Lap2β and Emerin, but differs from the nuclear envelope by its fenestrations and the absence of the Lamin B Receptor and nuclear pore complexes. Reduction of exclusome frequency upon overexpressing Emerin's LEM-domain suggests a role for Emerin in plasmid DNA compartmentalization. Thus, cells distinguish extrachromosomal DNA and chromosomes and wrap them into similar yet distinct envelopes keeping the former in the exclusome but the latter in the nucleus, where transcription occurs.
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Affiliation(s)
- Laura Schenkel
- Institute of Biochemistry, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
- Molecular Life Science PhD Program, Life Science Zurich Graduate School, 8057 Zurich, Switzerland
| | - Xuan Wang
- Institute of Biochemistry, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
- Molecular Life Science PhD Program, Life Science Zurich Graduate School, 8057 Zurich, Switzerland
| | - Nhung Le
- Institute of Biochemistry, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
- Molecular Life Science PhD Program, Life Science Zurich Graduate School, 8057 Zurich, Switzerland
| | - Michael Burger
- Institute of Biochemistry, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
| | - Ruth Kroschewski
- Institute of Biochemistry, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 3, 8093 Zürich, Switzerland
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13
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Corbett AH, Fasken MB. Fellowship of two rings: Unprecedented insights into the structure of the yeast nuclear pore complex. Mol Cell 2023; 83:3232-3233. [PMID: 37738961 DOI: 10.1016/j.molcel.2023.08.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 08/29/2023] [Accepted: 08/29/2023] [Indexed: 09/24/2023]
Abstract
Akey et al.1 use complementary experimental approaches and AI-based structure prediction to reveal new details of the structure of the yeast nuclear pore complex, providing key insights into evolution, assembly, and nucleocytoplasmic transport mechanisms.
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Affiliation(s)
- Anita H Corbett
- Department of Biology, Emory College of Arts and Sciences, Atlanta, GA 30322, USA.
| | - Milo B Fasken
- Department of Biology, Emory College of Arts and Sciences, Atlanta, GA 30322, USA
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14
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Akey CW, Echeverria I, Ouch C, Nudelman I, Shi Y, Wang J, Chait BT, Sali A, Fernandez-Martinez J, Rout MP. Implications of a multiscale structure of the yeast nuclear pore complex. Mol Cell 2023; 83:3283-3302.e5. [PMID: 37738963 PMCID: PMC10630966 DOI: 10.1016/j.molcel.2023.08.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/23/2023] [Accepted: 08/24/2023] [Indexed: 09/24/2023]
Abstract
Nuclear pore complexes (NPCs) direct the nucleocytoplasmic transport of macromolecules. Here, we provide a composite multiscale structure of the yeast NPC, based on improved 3D density maps from cryogenic electron microscopy and AlphaFold2 models. Key features of the inner and outer rings were integrated into a comprehensive model. We resolved flexible connectors that tie together the core scaffold, along with equatorial transmembrane complexes and a lumenal ring that anchor this channel within the pore membrane. The organization of the nuclear double outer ring reveals an architecture that may be shared with ancestral NPCs. Additional connections between the core scaffold and the central transporter suggest that under certain conditions, a degree of local organization is present at the periphery of the transport machinery. These connectors may couple conformational changes in the scaffold to the central transporter to modulate transport. Collectively, this analysis provides insights into assembly, transport, and NPC evolution.
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Affiliation(s)
- Christopher W Akey
- Department of Pharmacology, Physiology and Biophysics, Boston University, Chobanian and Avedisian School of Medicine, 700 Albany Street, Boston, MA 02118, USA.
| | - Ignacia Echeverria
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Christna Ouch
- Department of Pharmacology, Physiology and Biophysics, Boston University, Chobanian and Avedisian School of Medicine, 700 Albany Street, Boston, MA 02118, USA; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St., Worcester, MA 01605, USA
| | - Ilona Nudelman
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA
| | - Yi Shi
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY, USA
| | - Junjie Wang
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY, USA
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Javier Fernandez-Martinez
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA; Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain; Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA.
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15
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Shen W, Meng A. Protocol for imaging nuclear pore complexes on isolated nuclei of zebrafish early embryos by field emission scanning electron microscopy. STAR Protoc 2023; 4:102341. [PMID: 37314919 PMCID: PMC10277586 DOI: 10.1016/j.xpro.2023.102341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/20/2023] [Accepted: 05/10/2023] [Indexed: 06/16/2023] Open
Abstract
Here, we present a protocol to observe the three-dimensional surface of nuclear pore complexes (NPCs) of vertebrate early embryos by field emission scanning electron microscopy (FESEM). We describe steps from zebrafish early embryo collection and nuclei exposure to FESEM sample preparation and final NPC state analysis. This approach provides an easy way to observe surface morphology of NPCs from the cytoplasmic side. Alternatively, additional purification steps after nuclei exposure supply intact nuclei for further mass spectrometry analysis or other utilization. For complete details on the use and execution of this protocol, please refer to Shen et al.1.
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Affiliation(s)
- Weimin Shen
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Anming Meng
- Laboratory of Molecular Developmental Biology, State Key Laboratory of Membrane Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China; Laboratory of Stem Cell Regulation, Guangzhou Laboratory, Guangzhou 510320, China.
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16
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Mich-Basso JD, Kühn B. Protocol to image and quantify nuclear pore complexes using high-resolution laser scanning confocal microscopy. STAR Protoc 2023; 4:102552. [PMID: 37651236 PMCID: PMC10495640 DOI: 10.1016/j.xpro.2023.102552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/13/2023] [Accepted: 08/10/2023] [Indexed: 09/02/2023] Open
Abstract
Nuclear pore complexes are pathways for nuclear-cytoplasmic communication that participate in chromatin organization. Here, we present a protocol to image and quantify the number of nuclear pore complexes in cells. We describe steps for cell plating and culture, immunofluorescence detection, and confocal microscopy visualization of nuclear pore complexes. We then detail quantification and 3D data analysis. This protocol utilizes digital thresholding under human supervision for quantification of nuclear pore complexes. For complete details on the use and execution of this protocol, please refer to Han et al.1.
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Affiliation(s)
- Jocelyn D Mich-Basso
- Division of Cardiology, Pediatric Institute for Heart Regeneration and Therapeutics (I-HRT), UPMC Children's Hospital of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA 15224, USA; Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA
| | - Bernhard Kühn
- Division of Cardiology, Pediatric Institute for Heart Regeneration and Therapeutics (I-HRT), UPMC Children's Hospital of Pittsburgh, 4401 Penn Avenue, Pittsburgh, PA 15224, USA; Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA.
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17
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Gandhimathi R, Pinotsi D, Köhler M, Mansfeld J, Ashiono C, Kleele T, Pawar S, Kutay U. Super-resolution microscopy reveals focal organization of ER-associated Y-complexes in mitosis. EMBO Rep 2023; 24:e56766. [PMID: 37469276 PMCID: PMC10481662 DOI: 10.15252/embr.202356766] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 07/03/2023] [Accepted: 07/03/2023] [Indexed: 07/21/2023] Open
Abstract
During mitotic entry of vertebrate cells, nuclear pore complexes (NPCs) are rapidly disintegrated. NPC disassembly is initiated by hyperphosphorylation of linker nucleoporins (Nups), which leads to the dissociation of FG repeat Nups and relaxation of the nuclear permeability barrier. However, less is known about disintegration of the huge nuclear and cytoplasmic rings, which are formed by annular assemblies of Y-complexes that are dissociated from NPCs as intact units. Surprisingly, we observe that Y-complex Nups display slower dissociation kinetics compared with other Nups during in vitro NPC disassembly, indicating a mechanistic difference in the disintegration of Y-based rings. Intriguingly, biochemical experiments reveal that a fraction of Y-complexes remains associated with mitotic ER membranes, supporting recent microscopic observations. Visualization of mitotic Y-complexes by super-resolution microscopy demonstrates that they form two classes of higher order assemblies: large clusters at kinetochores and small, focal ER-associated assemblies. These, however, lack features qualifying them as persisting ring-shaped subassemblies previously proposed to serve as structural templates for NPC reassembly during mitotic exit, which helps to refine current models of nuclear reassembly.
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Affiliation(s)
- Rojapriyadharshini Gandhimathi
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
- Molecular Life Sciences Ph.D. ProgramZurichSwitzerland
| | | | - Mario Köhler
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
| | - Jörg Mansfeld
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
- The Institute of Cancer ResearchLondonUK
| | - Caroline Ashiono
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
| | - Tatjana Kleele
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
| | - Sumit Pawar
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
- Present address:
Myllia BiotechnologyViennaAustria
| | - Ulrike Kutay
- Department of Biology, Institute of BiochemistryETH ZurichZurichSwitzerland
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18
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Cho UH, Hetzer MW. Caspase-mediated nuclear pore complex trimming in cell differentiation and endoplasmic reticulum stress. eLife 2023; 12:RP89066. [PMID: 37665327 PMCID: PMC10476967 DOI: 10.7554/elife.89066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023] Open
Abstract
During apoptosis, caspases degrade 8 out of ~30 nucleoporins to irreversibly demolish the nuclear pore complex. However, for poorly understood reasons, caspases are also activated during cell differentiation. Here, we show that sublethal activation of caspases during myogenesis results in the transient proteolysis of four peripheral Nups and one transmembrane Nup. 'Trimmed' NPCs become nuclear export-defective, and we identified in an unbiased manner several classes of cytoplasmic, plasma membrane, and mitochondrial proteins that rapidly accumulate in the nucleus. NPC trimming by non-apoptotic caspases was also observed in neurogenesis and endoplasmic reticulum stress. Our results suggest that caspases can reversibly modulate nuclear transport activity, which allows them to function as agents of cell differentiation and adaptation at sublethal levels.
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Affiliation(s)
- Ukrae H Cho
- Molecular and Cell Biology Laboratory, Salk Institute for Biological StudiesLa JollaUnited States
| | - Martin W Hetzer
- Molecular and Cell Biology Laboratory, Salk Institute for Biological StudiesLa JollaUnited States
- Institute of Science and Technology Austria (IST Austria)KlosterneuburgAustria
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19
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Abstract
The nuclear envelope (NE) is a spherical double membrane with elastic properties. How NE shape and elasticity are regulated by lipid chemistry is unknown. Here we discover lipid acyl chain unsaturation as essential for NE and nuclear pore complex (NPC) architecture and function. Increased lipid saturation rigidifies the NE and the endoplasmic reticulum into planar, polygonal membranes, which are fracture prone. These membranes exhibit a micron-scale segregation of lipids into ordered and disordered phases, excluding NPCs from the ordered phase. Balanced lipid saturation is required for NPC integrity, pore membrane curvature and nucleocytoplasmic transport. Oxygen deprivation amplifies the impact of saturated lipids, causing NE rigidification and rupture. Conversely, lipid droplets buffer saturated lipids to preserve NE architecture. Our study uncovers a fundamental link between lipid acyl chain structure and the integrity of the cell nucleus with implications for nuclear membrane malfunction in ischaemic tissues.
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Affiliation(s)
- Anete Romanauska
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Vienna, Austria
- Center for Molecular Biology, University of Vienna, Vienna, Austria
| | - Alwin Köhler
- Max Perutz Labs, Vienna Biocenter Campus (VBC), Vienna, Austria.
- Center for Molecular Biology, University of Vienna, Vienna, Austria.
- Center for Medical Biochemistry, Medical University of Vienna, Vienna, Austria.
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20
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Wang W, Jakobi A, Wu YL, Ries J, Stallinga S, Rieger B. Particle fusion of super-resolution data reveals the unit structure of Nup96 in Nuclear Pore Complex. Sci Rep 2023; 13:13327. [PMID: 37587192 PMCID: PMC10432550 DOI: 10.1038/s41598-023-39829-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 07/31/2023] [Indexed: 08/18/2023] Open
Abstract
Single molecule localization microscopy offers resolution nearly down to the molecular level with specific molecular labelling, and is thereby a promising tool for structural biology. In practice, however, the actual value to this field is limited primarily by incomplete fluorescent labelling of the structure. This missing information can be completed by merging information from many structurally identical particles in a particle fusion approach similar to cryo-EM single-particle analysis. In this paper, we present a data analysis of particle fusion results of fluorescently labelled Nup96 nucleoporins in the Nuclear Pore Complex to show that Nup96 occurs in a spatial arrangement of two rings of 8 units with two Nup96 copies per unit giving a total of 32 Nup96 copies per pore. We use Artificial Intelligence assisted modeling in Alphafold to extend the existing cryo-EM model of Nup96 to accurately pinpoint the positions of the fluorescent labels and show the accuracy of the match between fluorescent and cryo-EM data to be better than 3 nm in-plane and 5 nm out-of-plane.
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Affiliation(s)
- Wenxiu Wang
- Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Arjen Jakobi
- Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Yu-Le Wu
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Jonas Ries
- Department of Chromosome Biology, University of Vienna, Max-Perutz Labs, Center for Molecular Biology, Vienna, Austria
| | - Sjoerd Stallinga
- Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands.
| | - Bernd Rieger
- Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands.
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21
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Montel F. [Structural and mechanical plasticity of the nuclear pore]. Med Sci (Paris) 2023; 39:625-631. [PMID: 37695152 DOI: 10.1051/medsci/2023096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023] Open
Abstract
The nuclear pore, which can be seen as the gateway to the cell nucleus, is central to many processes including gene regulation. It is a complex and dynamic structure composed of more than 30 proteins present in multiple copies that allows the selective and directional transport of RNA and proteins. As shown by recent studies, it is able to adapt its overall structure to the state of the cell. These results suggest that the structural and mechanical plasticity of the nuclear pore is important for its function but also in the development of cancer or viral infections.
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Affiliation(s)
- Fabien Montel
- Laboratoire de physique, CNRS UMR 5672, école normale supérieure de Lyon, université de Lyon, F-69342 Lyon, France
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22
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King GA, Wettstein R, Varberg JM, Chetlapalli K, Walsh ME, Gillet LC, Hernández-Armenta C, Beltrao P, Aebersold R, Jaspersen SL, Matos J, Ünal E. Meiotic nuclear pore complex remodeling provides key insights into nuclear basket organization. J Cell Biol 2023; 222:e202204039. [PMID: 36515990 PMCID: PMC9754704 DOI: 10.1083/jcb.202204039] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 09/12/2022] [Accepted: 11/05/2022] [Indexed: 12/15/2022] Open
Abstract
Nuclear pore complexes (NPCs) are large proteinaceous assemblies that mediate nuclear compartmentalization. NPCs undergo large-scale structural rearrangements during mitosis in metazoans and some fungi. However, our understanding of NPC remodeling beyond mitosis remains limited. Using time-lapse fluorescence microscopy, we discovered that NPCs undergo two mechanistically separable remodeling events during budding yeast meiosis in which parts or all of the nuclear basket transiently dissociate from the NPC core during meiosis I and II, respectively. Meiosis I detachment, observed for Nup60 and Nup2, is driven by Polo kinase-mediated phosphorylation of Nup60 at its interface with the Y-complex. Subsequent reattachment of Nup60-Nup2 to the NPC core is facilitated by a lipid-binding amphipathic helix in Nup60. Preventing Nup60-Nup2 reattachment causes misorganization of the entire nuclear basket in gametes. Strikingly, meiotic nuclear basket remodeling also occurs in the distantly related fission yeast, Schizosaccharomyces pombe. Our study reveals a conserved and developmentally programmed aspect of NPC plasticity, providing key mechanistic insights into the nuclear basket organization.
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Affiliation(s)
- Grant A. King
- Department of Molecular and Cell Biology, University of California, Berkeley, CA
| | - Rahel Wettstein
- Institute of Biochemistry, ETH Zürich, Zürich, Switzerland
- Max Perutz Labs, University of Vienna, Vienna, Austria
| | | | | | - Madison E. Walsh
- Department of Molecular and Cell Biology, University of California, Berkeley, CA
| | - Ludovic C.J. Gillet
- Institute of Molecular Systems Biology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Claudia Hernández-Armenta
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Cambridge, UK
| | - Pedro Beltrao
- Institute of Molecular Systems Biology, Department of Biology, ETH Zürich, Zürich, Switzerland
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Cambridge, UK
| | - Ruedi Aebersold
- Institute of Molecular Systems Biology, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Sue L. Jaspersen
- Stowers Institute for Medical Research, Kansas City, MO
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS
| | - Joao Matos
- Institute of Biochemistry, ETH Zürich, Zürich, Switzerland
- Max Perutz Labs, University of Vienna, Vienna, Austria
| | - Elçin Ünal
- Department of Molecular and Cell Biology, University of California, Berkeley, CA
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23
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Veldsink AC, Veenhoff LM. How to unravel a basket: NPC reorganization during meiosis. J Cell Biol 2023; 222:e202301044. [PMID: 36689194 PMCID: PMC9884576 DOI: 10.1083/jcb.202301044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
While our understanding of the nuclear pore complex (NPC) structure is progressing spectacularly, the organizational principles of its nuclear basket remain elusive. In this issue, King et al. (2022. J. Cell Biol.https://doi.org/10.1083/jcb.202204039) provide new insights into the mechanisms that govern nuclear basket reorganization during meiosis.
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Affiliation(s)
- Annemiek C. Veldsink
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Liesbeth M. Veenhoff
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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24
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Spriggs CC, Cha G, Li J, Tsai B. Components of the LINC and NPC complexes coordinately target and translocate a virus into the nucleus to promote infection. PLoS Pathog 2022; 18:e1010824. [PMID: 36067270 PMCID: PMC9481172 DOI: 10.1371/journal.ppat.1010824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/16/2022] [Accepted: 08/22/2022] [Indexed: 11/18/2022] Open
Abstract
Nuclear entry represents the final and decisive infection step for most DNA viruses, although how this is accomplished by some viruses is unclear. Polyomavirus SV40 transports from the cell surface through the endosome, the endoplasmic reticulum, and the cytosol from where it enters the nucleus to cause infection. Here we elucidate the nuclear entry mechanism of SV40. Our results show that cytosol-localized SV40 is targeted to the nuclear envelope by directly engaging Nesprin-2 of the linker of nucleoskeleton and cytoskeleton (LINC) nuclear membrane complex. Additionally, we identify the NUP188 subunit of the nuclear pore complex (NPC) as a new Nesprin-2-interacting partner. This physical proximity positions the NPC to capture SV40 upon release from Nesprin-2, enabling the channel to facilitate nuclear translocation of the virus. Strikingly, SV40 disassembles during nuclear entry, generating a viral genome-VP1-VP3 subcomplex that efficiently crosses the NPC to enter the nucleus. Our results reveal how two major nuclear membrane protein complexes are exploited to promote targeting and translocation of a virus into the nucleus.
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Affiliation(s)
- Chelsey C. Spriggs
- Department of Cell and Developmental Biology, University of Michigan Medical School Ann Arbor, Michigan, United States of America
- * E-mail: (CCS); (BT)
| | - Grace Cha
- Department of Cell and Developmental Biology, University of Michigan Medical School Ann Arbor, Michigan, United States of America
| | - Jiaqian Li
- Department of Cell and Developmental Biology, University of Michigan Medical School Ann Arbor, Michigan, United States of America
- Department of Biological Chemistry, University of Michigan Medical School Ann Arbor, Michigan, United States of America
| | - Billy Tsai
- Department of Cell and Developmental Biology, University of Michigan Medical School Ann Arbor, Michigan, United States of America
- * E-mail: (CCS); (BT)
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25
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Liashkovich I, Rosso G, Shahin V. Atomic Force Microscopy for Structural and Biophysical Investigations on Nuclear Pore Complexes. Methods Mol Biol 2022; 2502:299-310. [PMID: 35412247 DOI: 10.1007/978-1-0716-2337-4_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Atomic force microscopy (AFM) enables simultaneous generation of topographical and biophysical maps of surfaces of biological samples at nanoresolution in physiologically relevant environments. Here, we describe the application of AFM to study nuclear pore complexes from structural and biophysical aspects.
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Affiliation(s)
- Ivan Liashkovich
- Institute of Physiology II, University of Münster, Münster, Germany
| | - Gonzalo Rosso
- Institute of Physiology II, University of Münster, Münster, Germany
| | - Victor Shahin
- Institute of Physiology II, University of Münster, Münster, Germany.
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26
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Aksenova V, Arnaoutov A, Dasso M. Analysis of Nucleoporin Function Using Inducible Degron Techniques. Methods Mol Biol 2022; 2502:129-150. [PMID: 35412236 DOI: 10.1007/978-1-0716-2337-4_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Over the last decade, the use of auxin-inducible degrons (AID) to control the stability of target proteins has revolutionized the field of cell biology. AID-mediated degradation helps to overcome multiple hurdles that have been encountered in studying multisubunit protein complexes, like the nuclear pore complex (NPC), using classical biochemical and genetic methods. We have used the AID system for acute depletion of individual members of the NPC, called nucleoporins, in order to distinguish their roles both within established NPCs and during NPC assembly.Here, we describe a protocol for CRISPR/Cas9-mediated gene targeting of genes with the AID tag. As an example, we describe a step-by-step protocol for targeting of the NUP153 gene. We also provide recommendations for screening strategies and integration of the sequence encoding the Transport Inhibitor Response 1 (TIR1) protein, a E3-Ubiquitin ligase subunit necessary for AID-dependent protein degradation. In addition, we discuss applications of the NUP-AID system and functional assays for analysis of NUP-AID tagged cell lines.
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Affiliation(s)
- Vasilisa Aksenova
- Division of Molecular and Cellular Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
| | - Alexei Arnaoutov
- Division of Molecular and Cellular Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Mary Dasso
- Division of Molecular and Cellular Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
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27
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Richardson AC, Fišerová J, Goldberg MW. NPC Structure in Model Organisms: Transmission Electron Microscopy and Immunogold Labeling Using High-Pressure Freezing/Freeze Substitution of Yeast, Worms, and Plants. Methods Mol Biol 2022; 2502:439-459. [PMID: 35412255 DOI: 10.1007/978-1-0716-2337-4_28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The nuclear pore complex (NPC) is a large elaborate structure embedded within the nuclear envelope, and intimately linked to the cytoskeleton, nucleoskeleton, and chromatin. Many different cargoes pass through its central channel and along the membrane at its periphery. The NPC is dismantled and reassembly, fully or partially, every cell cycle. In post-mitotic cells it consists of a combination of hyper-stable and highly dynamic proteins. Because of its size, dynamics, heterogeneity and integration, it is not possible to understand its structure and molecular function by any one, or even several, methods. For decades, and to this day, thin section transmission electron microscopy (TEM) has been a central tool for understanding the NPC, its associations, dynamics and role in transport as it can uniquely answer questions concerning fine structural detail within a cellular context. Using immunogold labeling specific components can also be identified within the ultrastructural context. Model organisms such as Saccharomyces cerevisiae are also central to NPC studies but have not been used extensively in structural work. This is because the cell wall presents difficulties with structural preservation and processing for TEM. In recent years, high-pressure freezing and freeze substitution have overcome these problems, as well as opened up methods to combine immunogold labeling with detailed structural analysis. Other model organisms such as the worm Caenorhabditis elegans and the plant Arabidopsis thaliana have been underused for similar reasons, but with similar solutions, which we present here. There are also many advantages to using these methods, adapted for use in mammalian systems, due to the instant nature of the initial fixation, to capture rapid processes such as nuclear transport, and preservation of dynamic membranes.
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Affiliation(s)
| | - Jindřiška Fišerová
- Department of Biology of the Cell Nucleus, Institute of Molecular Genetics AS CR, Prague, Czech Republic
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28
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Simon CS, Funaya C, Bauer J, Voβ Y, Machado M, Penning A, Klaschka D, Cyrklaff M, Kim J, Ganter M, Guizetti J. An extended DNA-free intranuclear compartment organizes centrosome microtubules in malaria parasites. Life Sci Alliance 2021; 4:e202101199. [PMID: 34535568 PMCID: PMC8473725 DOI: 10.26508/lsa.202101199] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 08/31/2021] [Accepted: 09/03/2021] [Indexed: 11/24/2022] Open
Abstract
Proliferation of Plasmodium falciparum in red blood cells is the cause of malaria and is underpinned by an unconventional cell division mode, called schizogony. Contrary to model organisms, P. falciparum replicates by multiple rounds of nuclear divisions that are not interrupted by cytokinesis. Organization and dynamics of critical nuclear division factors remain poorly understood. Centriolar plaques, the centrosomes of P. falciparum, serve as microtubule organizing centers and have an acentriolar, amorphous structure. The small size of parasite nuclei has precluded detailed analysis of intranuclear microtubule organization by classical fluorescence microscopy. We apply recently developed super-resolution and time-lapse imaging protocols to describe microtubule reconfiguration during schizogony. Analysis of centrin, nuclear pore, and microtubule positioning reveals two distinct compartments of the centriolar plaque. Whereas centrin is extranuclear, we confirm by correlative light and electron tomography that microtubules are nucleated in a previously unknown and extended intranuclear compartment, which is devoid of chromatin but protein-dense. This study generates a working model for an unconventional centrosome and enables a better understanding about the diversity of eukaryotic cell division.
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Affiliation(s)
- Caroline S Simon
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Charlotta Funaya
- Electron Microscopy Core Facility, Heidelberg University, Heidelberg, Germany
| | - Johanna Bauer
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Yannik Voβ
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Marta Machado
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
- Graduate Program in Areas of Basic and Applied Biology, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Alexander Penning
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Darius Klaschka
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Marek Cyrklaff
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Juyeop Kim
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Markus Ganter
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Julien Guizetti
- Centre for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
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29
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Guedán A, Donaldson CD, Caroe ER, Cosnefroy O, Taylor IA, Bishop KN. HIV-1 requires capsid remodelling at the nuclear pore for nuclear entry and integration. PLoS Pathog 2021; 17:e1009484. [PMID: 34543344 PMCID: PMC8483370 DOI: 10.1371/journal.ppat.1009484] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 09/30/2021] [Accepted: 09/04/2021] [Indexed: 11/18/2022] Open
Abstract
The capsid (CA) lattice of the HIV-1 core plays a key role during infection. From the moment the core is released into the cytoplasm, it interacts with a range of cellular factors that, ultimately, direct the pre-integration complex to the integration site. For integration to occur, the CA lattice must disassemble. Early uncoating or a failure to do so has detrimental effects on virus infectivity, indicating that an optimal stability of the viral core is crucial for infection. Here, we introduced cysteine residues into HIV-1 CA in order to induce disulphide bond formation and engineer hyper-stable mutants that are slower or unable to uncoat, and then followed their replication. From a panel of mutants, we identified three with increased capsid stability in cells and found that, whilst the M68C/E212C mutant had a 5-fold reduction in reverse transcription, two mutants, A14C/E45C and E180C, were able to reverse transcribe to approximately WT levels in cycling cells. Moreover, these mutants only had a 5-fold reduction in 2-LTR circle production, suggesting that not only could reverse transcription complete in hyper-stable cores, but that the nascent viral cDNA could enter the nuclear compartment. Furthermore, we observed A14C/E45C mutant capsid in nuclear and chromatin-associated fractions implying that the hyper-stable cores themselves entered the nucleus. Immunofluorescence studies revealed that although the A14C/E45C mutant capsid reached the nuclear pore with the same kinetics as wild type capsid, it was then retained at the pore in association with Nup153. Crucially, infection with the hyper-stable mutants did not promote CPSF6 re-localisation to nuclear speckles, despite the mutant capsids being competent for CPSF6 binding. These observations suggest that hyper-stable cores are not able to uncoat, or remodel, enough to pass through or dissociate from the nuclear pore and integrate successfully. This, is turn, highlights the importance of capsid lattice flexibility for nuclear entry. In conclusion, we hypothesise that during a productive infection, a capsid remodelling step takes place at the nuclear pore that releases the core complex from Nup153, and relays it to CPSF6, which then localises it to chromatin ready for integration.
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Affiliation(s)
- Anabel Guedán
- Retroviral Replication Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Callum D. Donaldson
- Retroviral Replication Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Eve R. Caroe
- Retroviral Replication Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Ophélie Cosnefroy
- Retroviral Replication Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Ian A. Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Kate N. Bishop
- Retroviral Replication Laboratory, The Francis Crick Institute, London, United Kingdom
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30
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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31
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Abstract
Nuclear pore complexes (NPCs) are large multi-protein complexes that control bidirectional trafficking of macromolecules between the nucleus and cytoplasm. This trafficking is highly regulated and participates in a considerably broader range of cellular activities, including defense responses against pathogens in plants. Recently, NPC is emerging as a platform to physically associate the underlying chromatin with the nuclear periphery, thus regulating chromatin structure and gene expression. For instance, NPC components have been shown to promote the formation of specific genomics loops, which is linked to transcriptional memory for rapid reactivation of genes. With newly developed techniques and tools, our insight in this area has been substantially advanced. This review summarizes recent works on the molecular function of NPC machinery as hubs for transcriptional regulation and compares systems between plant and non-plant organisms.
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Affiliation(s)
- Kentaro Tamura
- Department of Environmental and Life Sciences, University of Shizuoka, Shizuoka, 422-8526, Japan.
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32
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Abstract
The interior of nuclear pore complexes (NPCs) is densely filled with FG-nucleoporins that form a permeability barrier of a still-obscure nature. Celetti et al. (2019. J. Cell Biol.https://doi.org/10.1083/jcb.201907157) now reveal that FG-nucleoporins can undergo liquid-liquid phase separation and form liquid droplets that mimic permeability barrier properties of intact NPCs.
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Affiliation(s)
- Dorothee Dormann
- BioMedical Center, Cell Biology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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33
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Thevathasan JV, Kahnwald M, Cieśliński K, Hoess P, Peneti SK, Reitberger M, Heid D, Kasuba KC, Hoerner SJ, Li Y, Wu YL, Mund M, Matti U, Pereira PM, Henriques R, Nijmeijer B, Kueblbeck M, Sabinina VJ, Ellenberg J, Ries J. Nuclear pores as versatile reference standards for quantitative superresolution microscopy. Nat Methods 2019; 16:1045-1053. [PMID: 31562488 PMCID: PMC6768092 DOI: 10.1038/s41592-019-0574-9] [Citation(s) in RCA: 145] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 08/14/2019] [Indexed: 12/18/2022]
Abstract
Quantitative fluorescence and superresolution microscopy are often limited by insufficient data quality or artifacts. In this context, it is essential to have biologically relevant control samples to benchmark and optimize the quality of microscopes, labels and imaging conditions. Here, we exploit the stereotypic arrangement of proteins in the nuclear pore complex as in situ reference structures to characterize the performance of a variety of microscopy modalities. We created four genome edited cell lines in which we endogenously labeled the nucleoporin Nup96 with mEGFP, SNAP-tag, HaloTag or the photoconvertible fluorescent protein mMaple. We demonstrate their use (1) as three-dimensional resolution standards for calibration and quality control, (2) to quantify absolute labeling efficiencies and (3) as precise reference standards for molecular counting. These cell lines will enable the broader community to assess the quality of their microscopes and labels, and to perform quantitative, absolute measurements.
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Affiliation(s)
- Jervis Vermal Thevathasan
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | | | | | - Philipp Hoess
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Sudheer Kumar Peneti
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Manuel Reitberger
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Division of Stem Cells and Cancer, German Cancer Research Center, Heidelberg, Germany
| | - Daniel Heid
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Department for Applied Tumor Biology, Heidelberg University Hospital, Heidelberg, Germany
| | - Krishna Chaitanya Kasuba
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Eidgenössische Technische Hochschule Zurich, Department of Biosystems Science and Engineering, Basel, Switzerland
| | - Sarah Janice Hoerner
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences and Interdisciplinary Center for Neuroscience, Heidelberg University, Heidelberg, Germany
| | - Yiming Li
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Yu-Le Wu
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Markus Mund
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Department of Biochemistry, University of Geneva, Science 2, Genève, Switzerland
| | - Ulf Matti
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Pedro Matos Pereira
- MRC-Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Ricardo Henriques
- MRC-Laboratory for Molecular Cell Biology, University College London, London, UK
| | | | | | | | - Jan Ellenberg
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Jonas Ries
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany.
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Affiliation(s)
- Guillaume Holzer
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
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35
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Abstract
Nucleoporin subunits that generate the nuclear pore complex (NPC) are highly conserved in evolution. High-resolution structures of the NPC are available, but the actual NPC composition in yeast has only been quantified recently. Two studies reveal major differences between species, suggesting high flexibility in NPC structures during evolution.
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Affiliation(s)
- Yaron Shav-Tal
- The Mina and Everard Goodman Faculty of Life Sciences, and Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel.
| | - Timir Tripathi
- Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Umshing, Shillong 793022, Meghalaya, India.
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36
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Affiliation(s)
- Nan Li
- MassGeneral Institute for Neurodegenerative Disease (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Clotilde Lagier-Tourenne
- MassGeneral Institute for Neurodegenerative Disease (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
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37
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Miyake N, Tsukaguchi H, Koshimizu E, Shono A, Matsunaga S, Shiina M, Mimura Y, Imamura S, Hirose T, Okudela K, Nozu K, Akioka Y, Hattori M, Yoshikawa N, Kitamura A, Cheong HI, Kagami S, Yamashita M, Fujita A, Miyatake S, Tsurusaki Y, Nakashima M, Saitsu H, Ohashi K, Imamoto N, Ryo A, Ogata K, Iijima K, Matsumoto N. Biallelic Mutations in Nuclear Pore Complex Subunit NUP107 Cause Early-Childhood-Onset Steroid-Resistant Nephrotic Syndrome. Am J Hum Genet 2015; 97:555-66. [PMID: 26411495 DOI: 10.1016/j.ajhg.2015.08.013] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Accepted: 08/28/2015] [Indexed: 12/19/2022] Open
Abstract
The nuclear pore complex (NPC) is a huge protein complex embedded in the nuclear envelope. It has central functions in nucleocytoplasmic transport, nuclear framework, and gene regulation. Nucleoporin 107 kDa (NUP107) is a component of the NPC central scaffold and is an essential protein in all eukaryotic cells. Here, we report on biallelic NUP107 mutations in nine affected individuals who are from five unrelated families and show early-onset steroid-resistant nephrotic syndrome (SRNS). These individuals have pathologically focal segmental glomerulosclerosis, a condition that leads to end-stage renal disease with high frequency. NUP107 is ubiquitously expressed, including in glomerular podocytes. Three of four NUP107 mutations detected in the affected individuals hamper NUP107 binding to NUP133 (nucleoporin 133 kDa) and NUP107 incorporation into NPCs in vitro. Zebrafish with nup107 knockdown generated by morpholino oligonucleotides displayed hypoplastic glomerulus structures and abnormal podocyte foot processes, thereby mimicking the pathological changes seen in the kidneys of the SRNS individuals with NUP107 mutations. Considering the unique properties of the podocyte (highly differentiated foot-process architecture and slit membrane and the inability to regenerate), we propose a "podocyte-injury model" as the pathomechanism for SRNS due to biallelic NUP107 mutations.
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Affiliation(s)
- Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Hiroyasu Tsukaguchi
- Second Department of Internal Medicine, Kansai Medical University, Osaka 570-8507, Japan.
| | - Eriko Koshimizu
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Akemi Shono
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Satoko Matsunaga
- Department of Microbiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Masaaki Shiina
- Department of Biochemistry, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | | | - Shintaro Imamura
- National Research Institute of Fisheries Science, Yokohama 236-8648, Japan
| | - Tomonori Hirose
- Department of Molecular Biology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Koji Okudela
- Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Yuko Akioka
- Department of Pediatric Nephrology, Tokyo Women's Medical University, Tokyo 162-8666, Japan
| | - Motoshi Hattori
- Department of Pediatric Nephrology, Tokyo Women's Medical University, Tokyo 162-8666, Japan
| | - Norishige Yoshikawa
- Center for Clinical Research and Development, National Center for Child Health and Development, Tokyo 157-8535, Japan
| | - Akiko Kitamura
- Department of Immunology & Parasitology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503, Japan
| | - Hae Il Cheong
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul 03080, Korea; Research Coordination Center for Rare Diseases, Seoul National University Hospital, Seoul 03080, Korea; Kidney Research Institute, Medical Research Center, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Shoji Kagami
- Department of Pediatrics, University of Tokushima Graduate School, Tokushima 770-8503, Japan
| | - Michiaki Yamashita
- National Research Institute of Fisheries Science, Yokohama 236-8648, Japan
| | - Atsushi Fujita
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Satoko Miyatake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Yoshinori Tsurusaki
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Mitsuko Nakashima
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Hirotomo Saitsu
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Kenichi Ohashi
- Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, RIKEN, Wako 351-0198, Japan
| | - Akihide Ryo
- Department of Microbiology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Kazuhiro Ogata
- Department of Biochemistry, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan.
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Guo Y, Kim Y, Shimi T, Goldman RD, Zheng Y. Concentration-dependent lamin assembly and its roles in the localization of other nuclear proteins. Mol Biol Cell 2014; 25:1287-97. [PMID: 24523288 PMCID: PMC3982994 DOI: 10.1091/mbc.e13-11-0644] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 02/05/2014] [Accepted: 02/06/2014] [Indexed: 11/11/2022] Open
Abstract
The nuclear lamina (NL) consists of lamin polymers and proteins that bind to the polymers. Disruption of NL proteins such as lamin and emerin leads to developmental defects and human diseases. However, the expression of multiple lamins, including lamin-A/C, lamin-B1, and lamin-B2, in mammals has made it difficult to study the assembly and function of the NL. Consequently, it has been unclear whether different lamins depend on one another for proper NL assembly and which NL functions are shared by all lamins or are specific to one lamin. Using mouse cells deleted of all or different combinations of lamins, we demonstrate that the assembly of each lamin into the NL depends primarily on the lamin concentration present in the nucleus. When expressed at sufficiently high levels, each lamin alone can assemble into an evenly organized NL, which is in turn sufficient to ensure the even distribution of the nuclear pore complexes. By contrast, only lamin-A can ensure the localization of emerin within the NL. Thus, when investigating the role of the NL in development and disease, it is critical to determine the protein levels of relevant lamins and the intricate shared or specific lamin functions in the tissue of interest.
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Affiliation(s)
- Yuxuan Guo
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
| | - Youngjo Kim
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
| | - Takeshi Shimi
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Robert D. Goldman
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Yixian Zheng
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218
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39
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Neumann N, Lundin D, Poole AM. Comparative genomic evidence for a complete nuclear pore complex in the last eukaryotic common ancestor. PLoS One 2010; 5:e13241. [PMID: 20949036 PMCID: PMC2951903 DOI: 10.1371/journal.pone.0013241] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Accepted: 09/15/2010] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The Nuclear Pore Complex (NPC) facilitates molecular trafficking between nucleus and cytoplasm and is an integral feature of the eukaryote cell. It exhibits eight-fold rotational symmetry and is comprised of approximately 30 nucleoporins (Nups) in different stoichiometries. Nups are broadly conserved between yeast, vertebrates and plants, but few have been identified among other major eukaryotic groups. METHODOLOGY/PRINCIPAL FINDINGS We screened for Nups across 60 eukaryote genomes and report that 19 Nups (spanning all major protein subcomplexes) are found in all eukaryote supergroups represented in our study (Opisthokonts, Amoebozoa, Viridiplantae, Chromalveolates and Excavates). Based on parsimony, between 23 and 26 of 31 Nups can be placed in LECA. Notably, they include central components of the anchoring system (Ndc1 and Gp210) indicating that the anchoring system did not evolve by convergence, as has previously been suggested. These results significantly extend earlier results and, importantly, unambiguously place a fully-fledged NPC in LECA. We also test the proposal that transmembrane Pom proteins in vertebrates and yeasts may account for their variant forms of mitosis (open mitoses in vertebrates, closed among yeasts). The distribution of homologues of vertebrate Pom121 and yeast Pom152 is not consistent with this suggestion, but the distribution of fungal Pom34 fits a scenario wherein it was integral to the evolution of closed mitosis in ascomycetes. We also report an updated screen for vesicle coating complexes, which share a common evolutionary origin with Nups, and can be traced back to LECA. Surprisingly, we find only three supergroup-level differences (one gain and two losses) between the constituents of COPI, COPII and Clathrin complexes. CONCLUSIONS/SIGNIFICANCE Our results indicate that all major protein subcomplexes in the Nuclear Pore Complex are traceable to the Last Eukaryotic Common Ancestor (LECA). In contrast to previous screens, we demonstrate that our conclusions hold regardless of the position of the root of the eukaryote tree.
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Affiliation(s)
- Nadja Neumann
- Department of Molecular Biology and Functional Genomics, Stockholm University, Stockholm, Sweden
| | - Daniel Lundin
- Department of Molecular Biology and Functional Genomics, Stockholm University, Stockholm, Sweden
| | - Anthony M. Poole
- Department of Molecular Biology and Functional Genomics, Stockholm University, Stockholm, Sweden
- School of Biological Sciences and Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand
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40
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Abstract
To understand the cell, we need to determine the macromolecular assembly structures, which may consist of tens to hundreds of components. First, we review the varied experimental data that characterize the assemblies at several levels of resolution. We then describe computational methods for generating the structures using these data. To maximize completeness, resolution, accuracy, precision, and efficiency of the structure determination, a computational approach is required that uses spatial information from a variety of experimental methods. We propose such an approach, defined by its three main components: a hierarchical representation of the assembly, a scoring function consisting of spatial restraints derived from experimental data, and an optimization method that generates structures consistent with the data. This approach is illustrated by determining the configuration of the 456 proteins in the nuclear pore complex (NPC) from baker's yeast. With these tools, we are poised to integrate structural information gathered at multiple levels of the biological hierarchy--from atoms to cells--into a common framework.
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Affiliation(s)
- Frank Alber
- Department of Biopharmaceutical Sciences, and California Institute for Quantitative Biosciences, University of California at San Francisco, CA 94158-2330, USA.
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41
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Stankova L, Ziemba AJ, Zhilina ZV, Ebbinghaus SW. Mechanism of PNA transport to the nuclear compartment. Ann N Y Acad Sci 2007; 1082:27-30. [PMID: 17145921 DOI: 10.1196/annals.1348.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We evaluated the nuclear uptake of fluorescently labeled peptide nucleic acids and measured the binding of unlabeled peptide nucleic acids (PNAs) to the endogenous HER-2/neu promotor in digitonin-permeabilized SK-BR-3 cells. Fluorescently labeled PNAs readily enter the nucleus of digitonin-permeabilized cells, and binding to the chromosomal target sequence was detected with a bis-PNA. Nuclear uptake and target sequence binding were inhibited by N-ethylmaleimide (NEM) and GTPgammaS. We conclude that PNAs are transported into the nucleus through an energy-dependent process involving the nuclear pore complex.
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Affiliation(s)
- Lenka Stankova
- Arizona Cancer Center, University of Arizona, Tucson, Arizona 85724-5024, USA
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42
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Abstract
For genome multiplication hepadnaviruses use the transcriptional machinery of the cell that is found within the nucleus. Thus the viral genome has to be transported through the cytoplasm and nuclear pore. The intracytosolic translocation is facilitated by the viral capsid that surrounds the genome and that interacts with cellular microtubules. The subsequent passage through the nuclear pore complexes (NPC) is mediated by the nuclear transport receptors importin α and β. Importin α binds to the C-terminus of the capsid protein that comprises a nuclear localization signal (NLS). The exposure of the NLS is regulated and depends upon genome maturation and/or phosphorylation of the capsid protein. As for other karyophilic cargos using this pathway importin α interacts with importin β that facilitates docking of the import complex to the NPC and the passage through the pore. Being a unique strategy, the import of the viral capsid is incomplete in that it becomes arrested inside the nuclear basket, which is a cage-like structure on the karyoplasmic face of the NPC. Presumably only this compartment provides the factors that are required for capsid disassembly and genome release that is restricted to those capsids comprising a mature viral DNA genome.
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Affiliation(s)
- Michael Kann
- CNRS-REGER (UMR 5097), Bâtiment 3A, Université Bordeaux 2, 146 rue Leo Saignat, F-33076 Bordeaux Cedex, France.
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43
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Abstract
In eukaryotic cells, segregation of DNA replication and RNA biogenesis in the nucleus and protein synthesis in the cytoplasm poses the requirement of transporting thousands of macromolecules between the two cellular compartments. Transport between nucleus and cytoplasm is mediated by soluble receptors that recognize specific cargoes and carry them through the nuclear pore complex (NPC), the sole gateway between the two compartments at interphase. Nucleocytoplasmic transport is specific not only in terms of cargo recognition, but also in terms of directionality, with nuclear proteins imported into the nucleus and RNAs exported from it. How is directionality achieved? How can the receptors be both specific and versatile in recognizing a multitude of cargoes? And how can their interaction with NPCs allow fast translocation? We describe the molecular mechanisms underlying nucleocytoplasmic transport as they have been revealed by structural studies of the receptors and regulators in different steps of transport cycles.
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Affiliation(s)
- Atlanta Cook
- European Molecular Biology Laboratory, D-69117 Heidelberg, Germany.
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44
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Galy V, Askjaer P, Franz C, López-Iglesias C, Mattaj IW. MEL-28, a novel nuclear-envelope and kinetochore protein essential for zygotic nuclear-envelope assembly in C. elegans. Curr Biol 2006; 16:1748-56. [PMID: 16950114 DOI: 10.1016/j.cub.2006.06.067] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Revised: 05/16/2006] [Accepted: 06/01/2006] [Indexed: 10/24/2022]
Abstract
The nuclear envelope (NE) of eukaryotic cells separates nucleoplasm from cytoplasm, mediates nucleo-cytoplasmic transport, and contributes to the control of gene expression. The NE consists of three major components: the nuclear membranes, the nuclear pore complexes (NPCs), and the nuclear lamina. The list of identified NE proteins has increased considerably during recent years but is most likely not complete. In most eukaryotes, the NE breaks down and is then reassembled during mitosis. The assembly of NPCs and the association and fusion of nuclear membranes around decondensing chromosomes are tightly coordinated processes. Here, we report the identification and characterization of MEL-28, a large protein essential for the assembly of a functional NE in C. elegans embryos. RNAi depletion or genetic mutation of mel-28 severely impairs nuclear morphology and leads to abnormal distribution of both integral NE proteins and NPCs. The structural defects of the NE were associated with functional defects and lack of nuclear exclusion of soluble proteins. MEL-28 localizes to NPCs during interphase, to kinetochores in early to middle mitosis then is widely distributed on chromatin late in mitosis. We show that MEL-28 is an early-assembling, stable NE component required for all aspects of NE assembly.
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Affiliation(s)
- Vincent Galy
- European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
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Abstract
The International Symposium on Ran and the Cell Cycle was held on October 1-4, 2005, at the Awaji Island Resort near Osaka, to celebrate the career and scientific achievements of Professor Takeharu Nishimoto. One hundred of his former lab members, collaborators and other scientific colleagues from around the world attended the symposium organized by Mary Dasso (National Institutes of Health) and Yoshihiro Yoneda (Osaka University). The program was divided into sessions on cell cycle and chromosomes, nuclear import and export of proteins and RNA, nuclear envelope and the nuclear pore complex, and RCC1 and chromatin. Dr. Nishimoto's retirement from Kyushu University is a perfect time to look back at the history of Ran and RCC1, assess the current state of the field, and discuss the challenges that remain in order to unravel the complexities of the Ran GTPase system.
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Affiliation(s)
- Shelley Sazer
- Verna and Marrs Mclean Department of Biochemistry, Baylor College of Medicine, Houston, Texas 77030, USA.
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Matsuura Y, Stewart M. Nup50/Npap60 function in nuclear protein import complex disassembly and importin recycling. EMBO J 2005; 24:3681-9. [PMID: 16222336 PMCID: PMC1276725 DOI: 10.1038/sj.emboj.7600843] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2005] [Accepted: 09/20/2005] [Indexed: 11/09/2022] Open
Abstract
Nuclear import of proteins containing classical nuclear localization signals (NLS) is mediated by the importin-alpha:beta complex that binds cargo in the cytoplasm and facilitates its passage through nuclear pores, after which nuclear RanGTP dissociates the import complex and the importins are recycled. In vertebrates, import is stimulated by nucleoporin Nup50, which has been proposed to accompany the import complex through nuclear pores. However, we show here that the Nup50 N-terminal domain actively displaces NLSs from importin-alpha, which would be more consistent with Nup50 functioning to coordinate import complex disassembly and importin recycling. The crystal structure of the importin-alpha:Nup50 complex shows that Nup50 binds at two sites on importin-alpha. One site overlaps the secondary NLS-binding site, whereas the second extends along the importin-alpha C-terminus. Mutagenesis indicates that interaction at both sites is required for Nup50 to displace NLSs. The Cse1p:Kap60p:RanGTP complex structure suggests how Nup50 is then displaced on formation of the importin-alpha export complex. These results provide a rationale for understanding the series of interactions that orchestrate the terminal steps of nuclear protein import.
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Affiliation(s)
- Yoshiyuki Matsuura
- MRC Laboratory of Molecular Biology, Cambridge, UK
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan
| | - Murray Stewart
- MRC Laboratory of Molecular Biology, Cambridge, UK
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK. Tel.: +44 1223 402463; Fax: +44 1223 213556; E-mail:
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Junghans P, Kaehne T, Beyer M, Metges CC, Schwerin M. Dietary protein-related changes in hepatic transcription correspond to modifications in hepatic protein expression in growing pigs. J Nutr 2004; 134:43-7. [PMID: 14704291 DOI: 10.1093/jn/134.1.43] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In a previous investigation we showed by expression profiling based on transcription analysis using differential display RT-PCR (DDRT-PCR) and real-time RT-PCR that a soy protein diet (SPI) significantly changes the hepatic transcription pattern compared with a casein diet (CAS). The present study was conducted to determine whether the transcriptional modulation is translated into protein expression. The hepatic mRNA abundance of four genes (EP24.16, LC3, NPAP60L, RFC2) that showed diet-related expression in previous DDRT-PCR experiments was analyzed by real-time RT-PCR. Two pigs that showed the most prominent SPI-related changes of transcription and two casein-fed pigs were selected and their hepatic protein pattern was studied comparatively by two-dimensional gel electrophoresis and peptide mass fingerprinting. The two-dimensional protein gel electrophoresis revealed a predominant SPI-associated upregulation of protein expression that corresponded to the results of the mRNA study. Of 380 diet-related protein spots displayed, 215 appeared exclusively or enlarged in the two SPI pigs; 10 of 39 diet-related expressed protein spots extracted could be identified by peptide mass fingerprinting and database search. Compared with the transcriptomics approach, the proteomics approach led in part to the identification of the same diet-associated expressed molecules (plasminogen, trypsin, phospholipase A2, glutathione-S-transferase alpha, retinal binding protein) or at least molecules belonging to the same metabolic pathways (protein and amino acid metabolism, oxidative stress response, lipid metabolism). The present results at the proteome level confirm SPI-related increased oxidative stress response and significant effects on protein biosynthesis already observed at the transcriptome level.
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Affiliation(s)
- Peter Junghans
- Research Units Nutritional Physiology Oskar Kellner, Research Institute for the Biology of Farm Animals Dummerstorf, D-18196 Dummerstorf, Germany
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Abstract
beta-Catenin nuclear import has been found to be independent of classical nuclear localization signal (NLS) nuclear import factors. Here, we test the hypothesis that beta-catenin interacts directly with nuclear pore proteins to mediate its own transport. We show that beta-catenin, unlike importin-beta, does not interact detectably with Phe/Gly(FG)-repeat-rich nuclear pore proteins or nucleoporins (Nups). Moreover, unlike NLS-containing proteins, beta-catenin nuclear import is not inhibited by wheat germ agglutinin (WGA) or excess importin-beta. These results suggest beta-catenin nuclear translocation does not involve direct interactions with FG-Nups. However, beta-catenin has two regions that can target it to the nucleus, and its import is cold sensitive, indicating that beta-catenin nuclear import is still an active process. Transport is blocked by a soluble form of the C-cadherin cytoplasmic domain, suggesting that masking of the nuclear targeting signal may be a mechanism of regulating beta-catenin subcellular localization.
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Affiliation(s)
- Eun-Kyung Suh
- Neuroscience Program, Weill Graduate School of Medical Sciences of Cornell University, New York, NY 10021, USA
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Abstract
The human immunodeficiency virus type 1 integrase protein has karyophilic properties; that is, it localizes to the cell nucleus according to a range of assays. As an essential component of the preintegration complex, it has been suggested that the karyophilic properties of integrase might facilitate transport of the preintegration complex through the nuclear pore complexes of nondividing cells. However, no experiments have satisfactorily identified a nuclear localization signal within integrase. In this work, we investigated the karyophilic properties of integrase in intact cells with hopes of identifying a genuine transferable nuclear localization signal. Our results confirm that integrase tightly binds chromosomal DNA in vivo. However, our analysis determined that large integrase fusion proteins are unable to access the nucleus, indicating that integrase might lack a transferable nuclear localization signal. In addition, we present several lines of evidence to indicate that DNA binding might facilitate integrase nuclear accumulation. Furthermore, our data indicate integrase is degraded in the cytoplasm by a proteasome-dependent process, an event that probably contributes to the apparent nuclear accumulation of integrase. These results provide new insight into human immunodeficiency virus type 1 integrase intracellular dynamics.
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Affiliation(s)
- Eric Devroe
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
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