1
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Penzo A, Palancade B. Puzzling out nuclear pore complex assembly. FEBS Lett 2023; 597:2705-2727. [PMID: 37548888 DOI: 10.1002/1873-3468.14713] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/12/2023] [Accepted: 07/17/2023] [Indexed: 08/08/2023]
Abstract
Nuclear pore complexes (NPCs) are sophisticated multiprotein assemblies embedded within the nuclear envelope and controlling the exchanges of molecules between the cytoplasm and the nucleus. In this review, we summarize the mechanisms by which these elaborate complexes are built from their subunits, the nucleoporins, based on our ever-growing knowledge of NPC structural organization and on the recent identification of additional features of this process. We present the constraints faced during the production of nucleoporins, their gathering into oligomeric complexes, and the formation of NPCs within nuclear envelopes, and review the cellular strategies at play, from co-translational assembly to the enrolment of a panel of cofactors. Remarkably, the study of NPCs can inform our perception of the biogenesis of multiprotein complexes in general - and vice versa.
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Affiliation(s)
- Arianna Penzo
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Benoit Palancade
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
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2
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Kuiper EFE, Prophet SM, Schlieker C. Coordinating nucleoporin condensation and nuclear pore complex assembly. FEBS Lett 2023; 597:2534-2545. [PMID: 37620293 DOI: 10.1002/1873-3468.14725] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/24/2023] [Accepted: 08/10/2023] [Indexed: 08/26/2023]
Abstract
The nuclear pore complex (NPC) is among the most elaborate protein complexes in eukaryotes. While ribosomes and proteasomes are known to require dedicated assembly machinery, our understanding of NPC assembly is at a relatively early stage. Defects in NPC assembly or homeostasis are tied to movement disorders, including dystonia and amyotrophic lateral sclerosis (ALS), as well as aging, requiring a better understanding of these processes to enable therapeutic intervention. Here, we discuss recent progress in the understanding of NPC assembly and highlight how related defects in human disorders can shed light on NPC biogenesis. We propose that the condensation of phenylalanine-glycine repeat nucleoporins needs to be carefully controlled during NPC assembly to prevent aberrant condensation, aggregation, or amyloid formation.
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Affiliation(s)
- E F Elsiena Kuiper
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT, USA
| | - Sarah M Prophet
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT, USA
| | - Christian Schlieker
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT, USA
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
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3
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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] [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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4
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Amm I, Weberruss M, Hellwig A, Schwarz J, Tatarek-Nossol M, Lüchtenborg C, Kallas M, Brügger B, Hurt E, Antonin W. Distinct domains in Ndc1 mediate its interaction with the Nup84 complex and the nuclear membrane. J Cell Biol 2023; 222:e202210059. [PMID: 37154843 PMCID: PMC10165475 DOI: 10.1083/jcb.202210059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 01/31/2023] [Accepted: 03/17/2023] [Indexed: 05/10/2023] Open
Abstract
Nuclear pore complexes (NPCs) are embedded in the nuclear envelope and built from ∼30 different nucleoporins (Nups) in multiple copies, few are integral membrane proteins. One of these transmembrane nucleoporins, Ndc1, is thought to function in NPC assembly at the fused inner and outer nuclear membranes. Here, we show a direct interaction of Ndc1's transmembrane domain with Nup120 and Nup133, members of the pore membrane coating Y-complex. We identify an amphipathic helix in Ndc1's C-terminal domain binding highly curved liposomes. Upon overexpression, this amphipathic motif is toxic and dramatically alters the intracellular membrane organization in yeast. Ndc1's amphipathic motif functionally interacts with related motifs in the C-terminus of the nucleoporins Nup53 and Nup59, important for pore membrane binding and interconnecting NPC modules. The essential function of Ndc1 can be suppressed by deleting the amphipathic helix from Nup53. Our data indicate that nuclear membrane and presumably NPC biogenesis depends on a balanced ratio between amphipathic motifs in diverse nucleoporins.
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Affiliation(s)
- Ingo Amm
- Heidelberg University Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Marion Weberruss
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
| | - Andrea Hellwig
- Department of Neurobiology, Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Johannes Schwarz
- Heidelberg University Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Marianna Tatarek-Nossol
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
| | - Christian Lüchtenborg
- Heidelberg University Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Martina Kallas
- Heidelberg University Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Britta Brügger
- Heidelberg University Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Ed Hurt
- Heidelberg University Biochemistry Center (BZH), University of Heidelberg, Heidelberg, Germany
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, Aachen, Germany
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5
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Kralt A, Wojtynek M, Fischer JS, Agote-Aran A, Mancini R, Dultz E, Noor E, Uliana F, Tatarek-Nossol M, Antonin W, Onischenko E, Medalia O, Weis K. An amphipathic helix in Brl1 is required for nuclear pore complex biogenesis in S. cerevisiae. eLife 2022; 11:78385. [PMID: 36000978 PMCID: PMC9402233 DOI: 10.7554/elife.78385] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 08/03/2022] [Indexed: 12/28/2022] Open
Abstract
The nuclear pore complex (NPC) is the central portal for macromolecular exchange between the nucleus and cytoplasm. In all eukaryotes, NPCs assemble into an intact nuclear envelope (NE) during interphase, but the process of NPC biogenesis remains poorly characterized. Furthermore, little is known about how NPC assembly leads to the fusion of the outer and inner NE, and no factors have been identified that could trigger this event. Here, we characterize the transmembrane protein Brl1 as an NPC assembly factor required for NE fusion in budding yeast. Brl1 preferentially associates with NPC assembly intermediates and its depletion halts NPC biogenesis, leading to NE herniations that contain inner and outer ring nucleoporins but lack the cytoplasmic export platform. Furthermore, we identify an essential amphipathic helix in the luminal domain of Brl1 that mediates interactions with lipid bilayers. Mutations in this amphipathic helix lead to NPC assembly defects, and cryo-electron tomography analyses reveal multilayered herniations of the inner nuclear membrane with NPC-like structures at the neck, indicating a failure in NE fusion. Taken together, our results identify a role for Brl1 in NPC assembly and suggest a function of its amphipathic helix in mediating the fusion of the inner and outer nuclear membranes.
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Affiliation(s)
- Annemarie Kralt
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Matthias Wojtynek
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland.,Department of Biochemistry, University of Zurich, Zürich, Switzerland
| | - Jonas S Fischer
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Arantxa Agote-Aran
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Roberta Mancini
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Elisa Dultz
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Elad Noor
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Federico Uliana
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Marianna Tatarek-Nossol
- 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
| | - Evgeny Onischenko
- Department of Biological Sciences, University of Bergen, Bergen, Norway
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Zürich, Switzerland
| | - Karsten Weis
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
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6
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Stiekema M, Houben F, Verheyen F, Borgers M, Menzel J, Meschkat M, van Zandvoort MAMJ, Ramaekers FCS, Broers JLV. The Role of Lamins in the Nucleoplasmic Reticulum, a Pleiomorphic Organelle That Enhances Nucleo-Cytoplasmic Interplay. Front Cell Dev Biol 2022; 10:914286. [PMID: 35784476 PMCID: PMC9243388 DOI: 10.3389/fcell.2022.914286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/24/2022] [Indexed: 12/15/2022] Open
Abstract
Invaginations of the nuclear membrane occur in different shapes, sizes, and compositions. Part of these pleiomorphic invaginations make up the nucleoplasmic reticulum (NR), while others are merely nuclear folds. We define the NR as tubular invaginations consisting of either both the inner and outer nuclear membrane, or only the inner nuclear membrane. Specifically, invaginations of both the inner and outer nuclear membrane are also called type II NR, while those of only the inner nuclear membrane are defined as type I NR. The formation and structure of the NR is determined by proteins associated to the nuclear membrane, which induce a high membrane curvature leading to tubular invaginations. Here we review and discuss the current knowledge of nuclear invaginations and the NR in particular. An increase in tubular invaginations of the nuclear envelope is associated with several pathologies, such as laminopathies, cancer, (reversible) heart failure, and Alzheimer’s disease. Furthermore, viruses can induce both type I and II NR. In laminopathies, the amount of A-type lamins throughout the nucleus is generally decreased or the organization of lamins or lamin-associated proteins is disturbed. Also, lamin overexpression or modulation of lamin farnesylation status impacts NR formation, confirming the importance of lamin processing in NR formation. Virus infections reorganize the nuclear lamina via (de)phosphorylation of lamins, leading to an uneven thickness of the nuclear lamina and in turn lobulation of the nuclear membrane and the formation of invaginations of the inner nuclear membrane. Since most studies on the NR have been performed with cell cultures, we present additional proof for the existence of these structures in vivo, focusing on a variety of differentiated cardiovascular and hematopoietic cells. Furthermore, we substantiate the knowledge of the lamin composition of the NR by super-resolution images of the lamin A/C and B1 organization. Finally, we further highlight the essential role of lamins in NR formation by demonstrating that (over)expression of lamins can induce aberrant NR structures.
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Affiliation(s)
- Merel Stiekema
- Department of Genetics and Cell Biology, Maastricht University Medical Centre, Maastricht, Netherlands
- GROW-School for Oncology and Reproduction, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Frederik Houben
- Department of Genetics and Cell Biology, Maastricht University Medical Centre, Maastricht, Netherlands
- Department of Healthcare, PXL University College, Hasselt, Belgium
| | - Fons Verheyen
- Department of Genetics and Cell Biology, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Marcel Borgers
- Department of Genetics and Cell Biology, Maastricht University Medical Centre, Maastricht, Netherlands
| | | | | | - Marc A. M. J. van Zandvoort
- Department of Genetics and Cell Biology, Maastricht University Medical Centre, Maastricht, Netherlands
- GROW-School for Oncology and Reproduction, Maastricht University Medical Centre, Maastricht, Netherlands
- CARIM-School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, Netherlands
- Institute for Molecular Cardiovascular Research IMCAR, RWTH Aachen University, Aachen, Germany
| | - Frans C. S. Ramaekers
- Department of Genetics and Cell Biology, Maastricht University Medical Centre, Maastricht, Netherlands
- GROW-School for Oncology and Reproduction, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Jos L. V. Broers
- Department of Genetics and Cell Biology, Maastricht University Medical Centre, Maastricht, Netherlands
- GROW-School for Oncology and Reproduction, Maastricht University Medical Centre, Maastricht, Netherlands
- CARIM-School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, Netherlands
- *Correspondence: Jos L. V. Broers,
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7
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Zhukov A, Popov V. Synthesis of C 20-38 Fatty Acids in Plant Tissues. Int J Mol Sci 2022; 23:ijms23094731. [PMID: 35563119 PMCID: PMC9101283 DOI: 10.3390/ijms23094731] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/18/2022] [Accepted: 04/22/2022] [Indexed: 02/06/2023] Open
Abstract
Very-long-chain fatty acids (VLCFA) are involved in a number of important plant physiological functions. Disorders in the expression of genes involved in the synthesis of VLCFA lead to a number of phenotypic consequences, ranging from growth retardation to the death of embryos. The elongation of VLCFA in the endoplasmic reticulum (ER) is carried out by multiple elongase complexes with different substrate specificities and adapted to the synthesis of a number of products required for a number of metabolic pathways. The information about the enzymes involved in the synthesis of VLCFA with more than 26 atoms of Carbon is rather poor. Recently, genes encoding enzymes involved in the synthesis of both regular-length fatty acids and VLCFA have been discovered and investigated. Polyunsaturated VLCFA in plants are formed mainly by 20:1 elongation into new monounsaturated acids, which are then imported into chloroplasts, where they are further desaturated. The formation of saturated VLCFA and their further transformation into a number of aliphatic compounds included in cuticular waxes and suberin require the coordinated activity of a large number of different enzymes.
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8
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Matsuda A, Mofrad MRK. On the nuclear pore complex and its emerging role in cellular mechanotransduction. APL Bioeng 2022; 6:011504. [PMID: 35308827 PMCID: PMC8916845 DOI: 10.1063/5.0080480] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/21/2022] [Indexed: 12/13/2022] Open
Abstract
The nuclear pore complex (NPC) is a large protein assembly that perforates the nuclear envelope and provides a sole gateway for traffic between the cytoplasm and the nucleus. The NPC controls the nucleocytoplasmic transport by selectively allowing cargoes such as proteins and mRNA to pass through its central channel, thereby playing a vital role in protecting the nuclear component and regulating gene expression and protein synthesis. The selective transport through the NPC originates from its exquisite molecular structure featuring a large scaffold and the intrinsically disordered central channel domain, but the exact mechanism underlying the selective transport remains elusive and is the subject of various, often conflicting, hypotheses. Moreover, recent studies have suggested a new role for the NPC as a mechanosensor, where the NPC changes its channel diameter depending on the nuclear envelope tension, altering the molecular transportability through this nanopore. In this mini-review, we summarize the current understandings of the selective nature of the NPC and discuss its emerging role in cellular mechanotransduction.
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Affiliation(s)
- Atsushi Matsuda
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
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9
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Cibulka J, Bisaccia F, Radisavljević K, Gudino Carrillo RM, Köhler A. Assembly principle of a membrane-anchored nuclear pore basket scaffold. SCIENCE ADVANCES 2022; 8:eabl6863. [PMID: 35148185 PMCID: PMC8836807 DOI: 10.1126/sciadv.abl6863] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Nuclear pore complexes (NPCs) are membrane-embedded gatekeepers of traffic between the nucleus and cytoplasm. Key features of the NPC symmetric core have been elucidated, but little is known about the NPC basket, a prominent structure with numerous roles in gene expression. Studying the basket was hampered by its instability and connection to the inner nuclear membrane (INM). Here, we reveal the assembly principle of the yeast NPC basket by reconstituting a recombinant Nup60-Mlp1-Nup2 scaffold on a synthetic membrane. Nup60 serves as the basket's flexible suspension cable, harboring an array of short linear motifs (SLiMs). These bind multivalently to the INM, the coiled-coil protein Mlp1, the FG-nucleoporin Nup2, and the NPC core. We suggest that SLiMs, embedded in disordered regions, allow the basket to adapt its structure in response to bulky cargo and changes in gene expression. Our study opens avenues for the higher-order reconstitution of basket-anchored NPC assemblies on membranes.
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10
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Akey CW, Singh D, Ouch C, Echeverria I, Nudelman I, Varberg JM, Yu Z, Fang F, Shi Y, Wang J, Salzberg D, Song K, Xu C, Gumbart JC, Suslov S, Unruh J, Jaspersen SL, Chait BT, Sali A, Fernandez-Martinez J, Ludtke SJ, Villa E, Rout MP. Comprehensive structure and functional adaptations of the yeast nuclear pore complex. Cell 2022; 185:361-378.e25. [PMID: 34982960 PMCID: PMC8928745 DOI: 10.1016/j.cell.2021.12.015] [Citation(s) in RCA: 89] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 11/26/2021] [Accepted: 12/13/2021] [Indexed: 02/06/2023]
Abstract
Nuclear pore complexes (NPCs) mediate the nucleocytoplasmic transport of macromolecules. Here we provide a structure of the isolated yeast NPC in which the inner ring is resolved by cryo-EM at sub-nanometer resolution to show how flexible connectors tie together different structural and functional layers. These connectors may be targets for phosphorylation and regulated disassembly in cells with an open mitosis. Moreover, some nucleoporin pairs and transport factors have similar interaction motifs, which suggests an evolutionary and mechanistic link between assembly and transport. We provide evidence for three major NPC variants that may foreshadow functional specializations at the nuclear periphery. Cryo-electron tomography extended these studies, providing a model of the in situ NPC with a radially expanded inner ring. Our comprehensive model reveals features of the nuclear basket and central transporter, suggests a role for the lumenal Pom152 ring in restricting dilation, and highlights structural plasticity that may be required for transport.
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Affiliation(s)
- Christopher W Akey
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, Boston, MA 02118, USA.
| | - Digvijay Singh
- Section of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Christna Ouch
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, Boston, MA 02118, USA; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Ignacia Echeverria
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, San Francisco, San Francisco, CA 94158, USA
| | - Ilona Nudelman
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA
| | | | - Zulin Yu
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Fei Fang
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yi Shi
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Junjie Wang
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY, USA
| | - Daniel Salzberg
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Kangkang Song
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Chen Xu
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Sergey Suslov
- Section of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Jay Unruh
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Sue L Jaspersen
- Stowers Institute for Medical Research, Kansas City, MO, USA; Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, 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
| | | | - Steven J Ludtke
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, 1 Baylor Plaza, Houston, Texas 77030, USA.
| | - Elizabeth Villa
- Section of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA; Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA.
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11
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Mauro MS, Celma G, Zimyanin V, Magaj MM, Gibson KH, Redemann S, Bahmanyar S. Ndc1 drives nuclear pore complex assembly independent of membrane biogenesis to promote nuclear formation and growth. eLife 2022; 11:75513. [PMID: 35852146 PMCID: PMC9296133 DOI: 10.7554/elife.75513] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 06/15/2022] [Indexed: 01/19/2023] Open
Abstract
The nuclear envelope (NE) assembles and grows from bilayer lipids produced at the endoplasmic reticulum (ER). How ER membrane incorporation coordinates with assembly of nuclear pore complexes (NPCs) to generate a functional NE is not well understood. Here, we use the stereotypical first division of the early C. elegans embryo to test the role of the membrane-associated nucleoporin Ndc1 in coupling NPC assembly to NE formation and growth. 3D-EM tomography of reforming and expanded NEs establishes that Ndc1 determines NPC density. Loss of ndc1 results in faster turnover of the outer scaffold nucleoporin Nup160 at the NE, providing an explanation for how Ndc1 controls NPC number. NE formation fails in the absence of both Ndc1 and the inner ring component Nup53, suggesting partially redundant roles in NPC assembly. Importantly, upregulation of membrane synthesis restored the slow rate of nuclear growth resulting from loss of ndc1 but not from loss of nup53. Thus, membrane biogenesis can be decoupled from Ndc1-mediated NPC assembly to promote nuclear growth. Together, our data suggest that Ndc1 functions in parallel with Nup53 and membrane biogenesis to control NPC density and nuclear size.
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Affiliation(s)
- Michael Sean Mauro
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew HavenUnited States
| | - Gunta Celma
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew HavenUnited States
| | - Vitaly Zimyanin
- Center for Membrane and Cell Physiology, University of VirginiaCharlottesvilleUnited States,Department of Molecular Physiology and Biological Physics, University of Virginia, School of MedicineCharlottesvilleUnited States
| | - Magdalena M Magaj
- Center for Membrane and Cell Physiology, University of VirginiaCharlottesvilleUnited States,Department of Molecular Physiology and Biological Physics, University of Virginia, School of MedicineCharlottesvilleUnited States
| | - Kimberley H Gibson
- Center for Cellular and Molecular Imaging: Electron Microscopy, Department of Cell Biology, Yale School of MedicineNew HavenUnited States
| | - Stefanie Redemann
- Center for Membrane and Cell Physiology, University of VirginiaCharlottesvilleUnited States,Department of Molecular Physiology and Biological Physics, University of Virginia, School of MedicineCharlottesvilleUnited States,Department of Cell Biology, University of VirginiaCharlottesvilleUnited States
| | - Shirin Bahmanyar
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew HavenUnited States
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12
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Hamed M, Antonin W. Dunking into the Lipid Bilayer: How Direct Membrane Binding of Nucleoporins Can Contribute to Nuclear Pore Complex Structure and Assembly. Cells 2021; 10:3601. [PMID: 34944108 PMCID: PMC8700311 DOI: 10.3390/cells10123601] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 02/07/2023] Open
Abstract
Nuclear pore complexes (NPCs) mediate the selective and highly efficient transport between the cytoplasm and the nucleus. They are embedded in the two membrane structure of the nuclear envelope at sites where these two membranes are fused to pores. A few transmembrane proteins are an integral part of NPCs and thought to anchor these complexes in the nuclear envelope. In addition, a number of nucleoporins without membrane spanning domains interact with the pore membrane. Here we review our current knowledge of how these proteins interact with the membrane and how this interaction can contribute to NPC assembly, stability and function as well as shaping of the pore membrane.
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Affiliation(s)
| | - Wolfram Antonin
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074 Aachen, Germany;
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13
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Brown JT, Haraczy AJ, Wilhelm CM, Belanger KD. Characterization of nuclear pore complex targeting domains in Pom152 in Saccharomyces cerevisiae. Biol Open 2021; 10:272274. [PMID: 34557894 PMCID: PMC8543022 DOI: 10.1242/bio.057661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 09/20/2021] [Indexed: 11/20/2022] Open
Abstract
Pom152 is a transmembrane protein within the nuclear pore complex (NPC) of fungi that is important for NPC assembly and structure. Pom152 is comprised of a short amino-terminal region that remains on the cytosolic side of the nuclear envelope (NE) and interacts with NPC proteins, a transmembrane domain, and a large, glycosylated carboxy-terminal domain within the NE lumen. Here we show that the N-terminal 200 amino acids of Pom152 that include only the amino-terminal and transmembrane regions are sufficient for localization to the NPC. Full-length, glycosylation-deficient, and truncated Pom152-GFP chimeras expressed in cells containing endogenous Pom152 localize to both NPCs and cortical endoplasmic reticulum (ER). Expression of Pom152-GFP fusions in pom152Δ cells results in detectable localization at only the NE by full-length and amino-terminal Pom152-GFP fusions, but continued retention at both the NE and ER for a chimera lacking just the carboxy-terminal 377 amino acids. Neither deletion of Pom152 nor its carboxy-terminal glycosylation sites altered the nuclear protein export rate of an Msn5/Kap142 protein cargo. These data narrow the Pom152 region sufficient for NPC localization and provide evidence that alterations in other domains may impact Pom152 targeting or affinity for the NPC. Summary: Pom152 is a transmembrane nucleoporin important for nuclear pore complex structure and synthesis. Here we further characterize Pom152, showing that the cytosolic and transmembrane domains are sufficient for NPC localization.
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14
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Deolal P, Mishra K. Regulation of diverse nuclear shapes: pathways working independently, together. Commun Integr Biol 2021; 14:158-175. [PMID: 34262635 PMCID: PMC8259725 DOI: 10.1080/19420889.2021.1939942] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/02/2021] [Accepted: 06/03/2021] [Indexed: 12/16/2022] Open
Abstract
Membrane-bound organelles provide physical and functional compartmentalization of biological processes in eukaryotic cells. The characteristic shape and internal organization of these organelles is determined by a combination of multiple internal and external factors. The maintenance of the shape of nucleus, which houses the genetic material within a double membrane bilayer, is crucial for a seamless spatio-temporal control over nuclear and cellular functions. Dynamic morphological changes in the shape of nucleus facilitate various biological processes. Chromatin packaging, nuclear and cytosolic protein organization, and nuclear membrane lipid homeostasis are critical determinants of overall nuclear morphology. As such, a multitude of molecular players and pathways act together to regulate the nuclear shape. Here, we review the known mechanisms governing nuclear shape in various unicellular and multicellular organisms, including the non-spherical nuclei and non-lamin-related structural determinants. The review also touches upon cellular consequences of aberrant nuclear morphologies.
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Affiliation(s)
- Pallavi Deolal
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Krishnaveni Mishra
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
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15
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Borah S, Thaller DJ, Hakhverdyan Z, Rodriguez EC, Isenhour AW, Rout MP, King MC, Lusk CP. Heh2/Man1 may be an evolutionarily conserved sensor of NPC assembly state. Mol Biol Cell 2021; 32:1359-1373. [PMID: 34010011 PMCID: PMC8694041 DOI: 10.1091/mbc.e20-09-0584] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Integral membrane proteins of the Lap2-emerin-MAN1 (LEM) family have emerged as important components of the inner nuclear membrane (INM) required for the functional and physical integrity of the nuclear envelope. However, like many INM proteins, there is limited understanding of the biochemical interaction networks that enable LEM protein function. Here, we show that Heh2/Man1 can interact with major scaffold components of the nuclear pore complex (NPC), specifically the inner ring complex (IRC), in evolutionarily distant yeasts. Although an N-terminal domain is required for Heh2 targeting to the INM, we demonstrate that more stable interactions with the NPC are mediated by a C-terminal winged helix (WH) domain, thus decoupling INM targeting and NPC binding. Inhibiting Heh2's interactions with the NPC by deletion of the Heh2 WH domain leads to NPC clustering. Interestingly, Heh2's association with NPCs can also be disrupted by knocking out several outer ring nucleoporins. Thus, Heh2's interaction with NPCs depends on the structural integrity of both major NPC scaffold complexes. We propose a model in which Heh2 acts as a sensor of NPC assembly state, which may be important for NPC quality control mechanisms and the segregation of NPCs during cell division.
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Affiliation(s)
- Sapan Borah
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | - David J Thaller
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | | | - Elisa C Rodriguez
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | - Anthony W Isenhour
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | | | - Megan C King
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
| | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520
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16
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One Ring to Rule them All? Structural and Functional Diversity in the Nuclear Pore Complex. Trends Biochem Sci 2021; 46:595-607. [PMID: 33563541 DOI: 10.1016/j.tibs.2021.01.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 02/07/2023]
Abstract
The nuclear pore complex (NPC) is the massive protein assembly that regulates the transport of macromolecules between the nucleus and the cytoplasm. Recent breakthroughs have provided major insights into the structure of the NPC in different eukaryotes, revealing a previously unsuspected diversity of NPC architectures. In parallel, the NPC has been shown to be a key player in regulating essential nuclear processes such as chromatin organization, gene expression, and DNA repair. However, our knowledge of the NPC structure has not been able to address the molecular mechanisms underlying its regulatory roles. We discuss potential explanations, including the coexistence of alternative NPC architectures with specific functional roles.
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17
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Corbeil D, Santos MF, Karbanová J, Kurth T, Rappa G, Lorico A. Uptake and Fate of Extracellular Membrane Vesicles: Nucleoplasmic Reticulum-Associated Late Endosomes as a New Gate to Intercellular Communication. Cells 2020; 9:cells9091931. [PMID: 32825578 PMCID: PMC7563309 DOI: 10.3390/cells9091931] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/18/2020] [Accepted: 08/20/2020] [Indexed: 02/06/2023] Open
Abstract
Extracellular membrane vesicles (EVs) are emerging as new vehicles in intercellular communication, but how the biological information contained in EVs is shared between cells remains elusive. Several mechanisms have been described to explain their release from donor cells and the initial step of their uptake by recipient cells, which triggers a cellular response. Yet, the intracellular routes and subcellular fate of EV content upon internalization remain poorly characterized. This is particularly true for EV-associated proteins and nucleic acids that shuttle to the nucleus of host cells. In this review, we will describe and discuss the release of EVs from donor cells, their uptake by recipient cells, and the fate of their cargoes, focusing on a novel intracellular route wherein small GTPase Rab7+ late endosomes containing endocytosed EVs enter into nuclear envelope invaginations and deliver their cargo components to the nucleoplasm of recipient cells. A tripartite protein complex composed of (VAMP)-associated protein A (VAP-A), oxysterol-binding protein (OSBP)-related protein-3 (ORP3), and Rab7 is essential for the transfer of EV-derived components to the nuclear compartment by orchestrating the particular localization of late endosomes in the nucleoplasmic reticulum.
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Affiliation(s)
- Denis Corbeil
- Biotechnology Center (BIOTEC) and Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47-49, 01307 Dresden, Germany; (J.K.)
- Correspondence: (D.C.); (A.L.); Tel.: +49-(0)351-463-40118 (D.C.); +1-(702)-777-3942 (A.L.); Fax: +49-(0)351-463-40244 (D.C.); +1-(702)-777-1758 (A.L.)
| | - Mark F. Santos
- College of Osteopathic Medicine, Touro University Nevada, 874 American Pacific Drive, Henderson, NV 89014, USA; (M.F.S.); (G.R.)
| | - Jana Karbanová
- Biotechnology Center (BIOTEC) and Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47-49, 01307 Dresden, Germany; (J.K.)
| | - Thomas Kurth
- Center for Regenerative Therapies Dresden and CMCB, Technische Universität Dresden, Fetscherstraße 105, 01307 Dresden, Germany; (T.K.)
| | - Germana Rappa
- College of Osteopathic Medicine, Touro University Nevada, 874 American Pacific Drive, Henderson, NV 89014, USA; (M.F.S.); (G.R.)
| | - Aurelio Lorico
- College of Osteopathic Medicine, Touro University Nevada, 874 American Pacific Drive, Henderson, NV 89014, USA; (M.F.S.); (G.R.)
- Mediterranean Institute of Oncology, Via Penninazzo, 11, 95029 Viagrande, Italy
- Correspondence: (D.C.); (A.L.); Tel.: +49-(0)351-463-40118 (D.C.); +1-(702)-777-3942 (A.L.); Fax: +49-(0)351-463-40244 (D.C.); +1-(702)-777-1758 (A.L.)
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18
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Burdine RD, Preston CC, Leonard RJ, Bradley TA, Faustino RS. Nucleoporins in cardiovascular disease. J Mol Cell Cardiol 2020; 141:43-52. [PMID: 32209327 DOI: 10.1016/j.yjmcc.2020.02.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 02/19/2020] [Accepted: 02/25/2020] [Indexed: 01/01/2023]
Abstract
Cardiovascular disease is a pressing health problem with significant global health, societal, and financial burdens. Understanding the molecular basis of polygenic cardiac pathology is thus essential to devising novel approaches for management and treatment. Recent identification of uncharacterized regulatory functions for a class of nuclear envelope proteins called nucleoporins offers the opportunity to understand novel putative mechanisms of cardiac disease development and progression. Consistent reports of nucleoporin deregulation associated with ischemic and dilated cardiomyopathies, arrhythmias and valvular disorders suggests that nucleoporin impairment may be a significant but understudied variable in cardiopathologic disorders. This review discusses and converges existing literature regarding nuclear pore complex proteins and their association with cardiac pathologies, and proposes a role for nucleoporins as facilitators of cardiac disease.
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Affiliation(s)
- Ryan D Burdine
- Genetics and Genomics Group, Sanford Research, 2301 E. 60(th) Street N., Sioux Falls, SD 57104, United States of America; School of Health Sciences, University of South Dakota, 414 E Clark St, Vermillion, SD 57069, United States of America
| | - Claudia C Preston
- Genetics and Genomics Group, Sanford Research, 2301 E. 60(th) Street N., Sioux Falls, SD 57104, United States of America
| | - Riley J Leonard
- Genetics and Genomics Group, Sanford Research, 2301 E. 60(th) Street N., Sioux Falls, SD 57104, United States of America
| | - Tyler A Bradley
- Genetics and Genomics Group, Sanford Research, 2301 E. 60(th) Street N., Sioux Falls, SD 57104, United States of America
| | - Randolph S Faustino
- Genetics and Genomics Group, Sanford Research, 2301 E. 60(th) Street N., Sioux Falls, SD 57104, United States of America; Department of Pediatrics, Sanford School of Medicine of the University of South Dakota, 1400 W. 22(nd) Street, Sioux Falls, SD 57105, United States of America.
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19
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A SUMO-dependent feedback loop senses and controls the biogenesis of nuclear pore subunits. Nat Commun 2018; 9:1665. [PMID: 29695777 PMCID: PMC5916902 DOI: 10.1038/s41467-018-03673-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 03/05/2018] [Indexed: 11/29/2022] Open
Abstract
While the activity of multiprotein complexes is crucial for cellular metabolism, little is known about the mechanisms that collectively control the expression of their components. Here, we investigate the regulations targeting the biogenesis of the nuclear pore complex (NPC), the macromolecular assembly mediating nucleocytoplasmic exchanges. Systematic analysis of RNA-binding proteins interactomes, together with in vivo and in vitro assays, reveal that a subset of NPC mRNAs are specifically bound by Hek2, a yeast hnRNP K-like protein. Hek2-dependent translational repression and protein turnover are further shown to finely tune the levels of NPC subunits. Strikingly, mutations or physiological perturbations altering pore integrity decrease the levels of the NPC-associated SUMO protease Ulp1, and trigger the accumulation of sumoylated versions of Hek2 unable to bind NPC mRNAs. Our results support the existence of a quality control mechanism involving Ulp1 as a sensor of NPC integrity and Hek2 as a repressor of NPC biogenesis. The nuclear pore complex is crucial for mediating nucleocytoplasmic exchanges. Here the authors use budding yeast to reveal a mechanism responsible of maintaining nucleoporin homeostasis by sensing changes in the complex integrity and further altering the metabolism of the corresponding mRNAs.
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20
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21
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Abstract
Despite the central role of Nuclear Pore Complexes (NPCs) as gatekeepers of RNA and protein transport between the cytoplasm and nucleoplasm, their large size and dynamic nature have impeded a full structural and functional elucidation. Here, we have determined a subnanometer precision structure for the entire 552-protein yeast NPC by satisfying diverse data including stoichiometry, a cryo-electron tomography map, and chemical cross-links. The structure reveals the NPC’s functional elements in unprecedented detail. The NPC is built of sturdy diagonal columns to which are attached connector cables, imbuing both strength and flexibility, while tying together all other elements of the NPC, including membrane-interacting regions and RNA processing platforms. Inwardly-directed anchors create a high density of transport factor-docking Phe-Gly repeats in the central channel, organized in distinct functional units. Taken together, this integrative structure allows us to rationalize the architecture, transport mechanism, and evolutionary origins of the NPC.
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22
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Cutler AA, Jackson JB, Corbett AH, Pavlath GK. Non-equivalence of nuclear import among nuclei in multinucleated skeletal muscle cells. J Cell Sci 2018; 131:jcs.207670. [PMID: 29361530 DOI: 10.1242/jcs.207670] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 12/21/2017] [Indexed: 01/01/2023] Open
Abstract
Skeletal muscle is primarily composed of large myofibers containing thousands of post-mitotic nuclei distributed throughout a common cytoplasm. Protein production and localization in specialized myofiber regions is crucial for muscle function. Myonuclei differ in transcriptional activity and protein accumulation, but how these differences among nuclei sharing a cytoplasm are achieved is unknown. Regulated nuclear import of proteins is one potential mechanism for regulating transcription spatially and temporally in individual myonuclei. The best-characterized nuclear localization signal (NLS) in proteins is the classical NLS (cNLS), but many other NLS motifs exist. We examined cNLS and non-cNLS reporter protein import using multinucleated muscle cells generated in vitro, revealing that cNLS and non-cNLS nuclear import differs among nuclei in the same cell. Investigation of cNLS nuclear import rates in isolated myofibers ex vivo confirmed differences in nuclear import rates among myonuclei. Analyzing nuclear import throughout myogenesis revealed that cNLS and non-cNLS import varies during differentiation. Taken together, our results suggest that both spatial and temporal regulation of nuclear import pathways are important in muscle cell differentiation and protein regionalization in myofibers.
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Affiliation(s)
- Alicia A Cutler
- Department of Pharmacology, Emory University, Atlanta, GA 30322, USA.,Graduate Program in Biochemistry, Cell and Developmental Biology, Emory University, Atlanta, GA 30322, USA
| | | | - Anita H Corbett
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Grace K Pavlath
- Department of Pharmacology, Emory University, Atlanta, GA 30322, USA
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23
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De Magistris P, Tatarek-Nossol M, Dewor M, Antonin W. A self-inhibitory interaction within Nup155 and membrane binding are required for nuclear pore complex formation. J Cell Sci 2018; 131:jcs.208538. [PMID: 29150488 DOI: 10.1242/jcs.208538] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 11/13/2017] [Indexed: 01/02/2023] Open
Abstract
Nuclear pore complexes (NPCs) are gateways through the nuclear envelope. How they form into a structure containing three rings and integrate into the nuclear envelope remains a challenging paradigm for coordinated assembly of macro-complexes. In vertebrates, the cytoplasmic and nucleoplasmic rings of NPCs are mostly formed by multiple copies of the Nup107-Nup160 complex, whereas the central, or inner ring is composed of Nup53, Nup93, Nup155 and the two paralogues Nup188 and Nup205. Inner ring assembly is only partially understood. Using in vitro nuclear assembly reactions, we show that direct pore membrane binding of Nup155 is crucial for NPC formation. Replacing full-length Nup155 with its N-terminal β-propeller allows assembly of the outer ring components to the NPC backbone that also contains Nup53. However, further assembly, especially recruitment of the Nup93 and Nup62 complexes, is blocked. Self-interaction between the N- and C-terminal domains of Nup155 has an auto-inhibitory function that prevents interaction between the N-terminus of Nup155 and the C-terminal region of Nup53. Nup93 can overcome this block by binding to Nup53, thereby promoting formation of the inner ring and the NPC.
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Affiliation(s)
- Paola De Magistris
- Friedrich Miescher Laboratory of the Max Planck Society, Spemannstraße 39, 72076 Tübingen, Germany.,Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074 Aachen, Germany
| | - Marianna Tatarek-Nossol
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074 Aachen, Germany
| | - Manfred Dewor
- Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074 Aachen, Germany
| | - Wolfram Antonin
- Friedrich Miescher Laboratory of the Max Planck Society, Spemannstraße 39, 72076 Tübingen, Germany .,Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074 Aachen, Germany
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24
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Hayama R, Rout MP, Fernandez-Martinez J. The nuclear pore complex core scaffold and permeability barrier: variations of a common theme. Curr Opin Cell Biol 2017. [PMID: 28624666 DOI: 10.1016/j.ceb.2017.05.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The study of the nuclear pore complex (NPC) is a fascinating endeavor, as it not only implies uncovering the 'engineering marvel' of its architecture and function, but also provides a key window into a significant evolutionary event: the origin of the eukaryotic cell. The combined efforts of many groups in the field, with the help of novel methodologies and new model organisms, are facilitating a much deeper understanding of this complex assembly. Here we cover recent advances on the characterization of the structure of the NPC scaffold and of the biophysical mechanisms that define the permeability barrier. We identify common architectural and functional principles between those two NPC compartments, expanding the previous protocoatomer hypothesis to suggest possible evolutionary origins for the FG nucleoporins and the NPC permeability barrier.
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Affiliation(s)
- Ryo Hayama
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA
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25
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Molecular Architecture of the Major Membrane Ring Component of the Nuclear Pore Complex. Structure 2017; 25:434-445. [PMID: 28162953 DOI: 10.1016/j.str.2017.01.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/06/2017] [Accepted: 01/19/2017] [Indexed: 02/06/2023]
Abstract
The membrane ring that equatorially circumscribes the nuclear pore complex (NPC) in the perinuclear lumen of the nuclear envelope is composed largely of Pom152 in yeast and its ortholog Nup210 (or Gp210) in vertebrates. Here, we have used a combination of negative-stain electron microscopy, nuclear magnetic resonance, and small-angle X-ray scattering methods to determine an integrative structure of the ∼120 kDa luminal domain of Pom152. Our structural analysis reveals that the luminal domain is formed by a flexible string-of-pearls arrangement of nine repetitive cadherin-like Ig-like domains, indicating an evolutionary connection between NPCs and the cell adhesion machinery. The 16 copies of Pom152 known to be present in the yeast NPC are long enough to form the observed membrane ring, suggesting how interactions between Pom152 molecules help establish and maintain the NPC architecture.
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26
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Beck M, Hurt E. The nuclear pore complex: understanding its function through structural insight. Nat Rev Mol Cell Biol 2016; 18:73-89. [PMID: 27999437 DOI: 10.1038/nrm.2016.147] [Citation(s) in RCA: 429] [Impact Index Per Article: 53.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Nuclear pore complexes (NPCs) fuse the inner and outer nuclear membranes to form channels across the nuclear envelope. They are large macromolecular assemblies with a complex composition and diverse functions. Apart from facilitating nucleocytoplasmic transport, NPCs are involved in chromatin organization, the regulation of gene expression and DNA repair. Understanding the molecular mechanisms underlying these functions has been hampered by a lack of structural knowledge about the NPC. The recent convergence of crystallographic and biochemical in vitro analysis of nucleoporins (NUPs), the components of the NPC, with cryo-electron microscopic imaging of the entire NPC in situ has provided first pseudo-atomic view of its central core and revealed that an unexpected network of short linear motifs is an important spatial organization principle. These breakthroughs have transformed the way we understand NPC structure, and they provide an important base for functional investigations, including the elucidation of the molecular mechanisms underlying clinically manifested mutations of the nucleocytoplasmic transport system.
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Affiliation(s)
- Martin Beck
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstrasse 1, Heidelberg D-69117, Germany
| | - Ed Hurt
- Biochemistry Center of Heidelberg University, INF328, Heidelberg D-69120, Germany
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27
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Smoyer CJ, Katta SS, Gardner JM, Stoltz L, McCroskey S, Bradford WD, McClain M, Smith SE, Slaughter BD, Unruh JR, Jaspersen SL. Analysis of membrane proteins localizing to the inner nuclear envelope in living cells. J Cell Biol 2016; 215:575-590. [PMID: 27831485 PMCID: PMC5119940 DOI: 10.1083/jcb.201607043] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/03/2016] [Accepted: 10/18/2016] [Indexed: 12/31/2022] Open
Abstract
Understanding the protein composition of the inner nuclear membrane (INM) is fundamental to elucidating its role in normal nuclear function and in disease; however, few tools exist to examine the INM in living cells, and the INM-specific proteome remains poorly characterized. Here, we adapted split green fluorescent protein (split-GFP) to systematically localize known and predicted integral membrane proteins in Saccharomyces cerevisiae to the INM as opposed to the outer nuclear membrane. Our data suggest that components of the endoplasmic reticulum (ER) as well as other organelles are able to access the INM, particularly if they contain a small extraluminal domain. By pairing split-GFP with fluorescence correlation spectroscopy, we compared the composition of complexes at the INM and ER, finding that at least one is unique: Sbh2, but not Sbh1, has access to the INM. Collectively, our work provides a comprehensive analysis of transmembrane protein localization to the INM and paves the way for further research into INM composition and function.
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Affiliation(s)
| | | | | | - Lynn Stoltz
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | - Scott McCroskey
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | | | | | - Sarah E Smith
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | | | - Jay R Unruh
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | - Sue L Jaspersen
- Stowers Institute for Medical Research, Kansas City, MO 64110 .,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160
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28
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Webster BM, Thaller DJ, Jäger J, Ochmann SE, Borah S, Lusk CP. Chm7 and Heh1 collaborate to link nuclear pore complex quality control with nuclear envelope sealing. EMBO J 2016; 35:2447-2467. [PMID: 27733427 DOI: 10.15252/embj.201694574] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 11/09/2022] Open
Abstract
The integrity of the nuclear envelope barrier relies on membrane remodeling by the ESCRTs, which seal nuclear envelope holes and contribute to the quality control of nuclear pore complexes (NPCs); whether these processes are mechanistically related remains poorly defined. Here, we show that the ESCRT-II/III chimera, Chm7, is recruited to a nuclear envelope subdomain that expands upon inhibition of NPC assembly and is required for the formation of the storage of improperly assembled NPCs (SINC) compartment. Recruitment to sites of NPC assembly is mediated by its ESCRT-II domain and the LAP2-emerin-MAN1 (LEM) family of integral inner nuclear membrane proteins, Heh1 and Heh2. We establish direct binding between Heh2 and the "open" forms of both Chm7 and the ESCRT-III, Snf7, and between Chm7 and Snf7. Interestingly, Chm7 is required for the viability of yeast strains where double membrane seals have been observed over defective NPCs; deletion of CHM7 in these strains leads to a loss of nuclear compartmentalization suggesting that the sealing of defective NPCs and nuclear envelope ruptures could proceed through similar mechanisms.
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Affiliation(s)
- Brant M Webster
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - David J Thaller
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Jens Jäger
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Sarah E Ochmann
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Sapan Borah
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
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29
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A model for coordinating nuclear mechanics and membrane remodeling to support nuclear integrity. Curr Opin Cell Biol 2016; 41:9-17. [PMID: 27031045 DOI: 10.1016/j.ceb.2016.03.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/10/2016] [Accepted: 03/11/2016] [Indexed: 11/20/2022]
Abstract
A polymer network of intranuclear lamin filaments underlies the nuclear envelope and provides mechanical stability to the nucleus in metazoans. Recent work demonstrates that the expression of A-type lamins scales positively with the stiffness of the cellular environment, thereby coupling nuclear and extracellular mechanics. Using the spectrin-actin network at the erythrocyte plasma membrane as a model, we contemplate how the relative stiffness of the nuclear scaffold impinges on the growing number of interphase-specific nuclear envelope remodeling events, including recently discovered, nuclear envelope-specialized quality control mechanisms. We suggest that a stiffer lamina impedes these remodeling events, necessitating local lamina remodeling and/or concomitant scaling of the efficacy of membrane-remodeling machineries that act at the nuclear envelope.
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30
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Schwartz TU. The Structure Inventory of the Nuclear Pore Complex. J Mol Biol 2016; 428:1986-2000. [PMID: 27016207 DOI: 10.1016/j.jmb.2016.03.015] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 03/09/2016] [Accepted: 03/15/2016] [Indexed: 11/18/2022]
Abstract
The nuclear pore complex (NPC) is the principal gateway for molecular exchange between nucleus and cytoplasm across the nuclear envelope. Due to its sheer size of estimated 50-112MDa and its complex buildup from about 500-1000 individual proteins, it is a difficult object to study for structural biologists. Here, I review the extensive ensemble of high-resolution structures of the building blocks of the NPC. Concurrent with the increase in size and complexity, these latest, large structures and assemblies can now be used as the basis for hybrid approaches, primarily in combination with cryo-electron microscopic analysis, generating the first structure-based assembly models of the NPC. Going forward, the structures will be critically important for a detailed analysis of the NPC, including function, evolution, and assembly.
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Affiliation(s)
- Thomas U Schwartz
- Department of Biology, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA
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31
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Abstract
Size and shape are important aspects of nuclear structure. While normal cells maintain nuclear size within a defined range, altered nuclear size and shape are associated with a variety of diseases. It is unknown if altered nuclear morphology contributes to pathology, and answering this question requires a better understanding of the mechanisms that control nuclear size and shape. In this review, we discuss recent advances in our understanding of the mechanisms that regulate nuclear morphology, focusing on nucleocytoplasmic transport, nuclear lamins, the endoplasmic reticulum, the cell cycle, and potential links between nuclear size and size regulation of other organelles. We then discuss the functional significance of nuclear morphology in the context of early embryonic development. Looking toward the future, we review new experimental approaches that promise to provide new insights into mechanisms of nuclear size control, in particular microfluidic-based technologies, and discuss how altered nuclear morphology might impact chromatin organization and physiology of diseased cells.
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Affiliation(s)
- Richik N Mukherjee
- a Department of Molecular Biology , University of Wyoming , Laramie , WY USA
| | - Pan Chen
- a Department of Molecular Biology , University of Wyoming , Laramie , WY USA
| | - Daniel L Levy
- a Department of Molecular Biology , University of Wyoming , Laramie , WY USA
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32
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Cairo L, Wozniak R. The Nuclear Transport Factor Kap121 Is Required for Stability of the Dam1 Complex and Mitotic Kinetochore Bi-orientation. Cell Rep 2016; 14:2440-50. [DOI: 10.1016/j.celrep.2016.02.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 11/04/2015] [Accepted: 02/04/2016] [Indexed: 12/30/2022] Open
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Interactome Mapping Reveals the Evolutionary History of the Nuclear Pore Complex. PLoS Biol 2016; 14:e1002365. [PMID: 26891179 PMCID: PMC4758718 DOI: 10.1371/journal.pbio.1002365] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 12/23/2015] [Indexed: 02/08/2023] Open
Abstract
The nuclear pore complex (NPC) is responsible for nucleocytoplasmic transport and constitutes a hub for control of gene expression. The components of NPCs from several eukaryotic lineages have been determined, but only the yeast and vertebrate NPCs have been extensively characterized at the quaternary level. Significantly, recent evidence indicates that compositional similarity does not necessarily correspond to homologous architecture between NPCs from different taxa. To address this, we describe the interactome of the trypanosome NPC, a representative, highly divergent eukaryote. We identify numerous new NPC components and report an exhaustive interactome, allowing assignment of trypanosome nucleoporins to discrete NPC substructures. Remarkably, despite retaining similar protein composition, there are exceptional architectural dissimilarities between opisthokont (yeast and vertebrates) and excavate (trypanosomes) NPCs. Whilst elements of the inner core are conserved, numerous peripheral structures are highly divergent, perhaps reflecting requirements to interface with divergent nuclear and cytoplasmic functions. Moreover, the trypanosome NPC has almost complete nucleocytoplasmic symmetry, in contrast to the opisthokont NPC; this may reflect divergence in RNA export processes at the NPC cytoplasmic face, as we find evidence supporting Ran-dependent mRNA export in trypanosomes, similar to protein transport. We propose a model of stepwise acquisition of nucleocytoplasmic mechanistic complexity and demonstrate that detailed dissection of macromolecular complexes provides fuller understanding of evolutionary processes. Dissection of the nuclear pore complex—an ancient eukaryotic molecular machine—exposes a fundamental divergence in structure and function between yeast and humans versus trypanosomes and provides insights into the evolution of the nucleus. Much of the core architecture of the eukaryotic cell was established over one billion years ago. Significantly, many cellular systems possess lineage-specific features, and architectural and compositional variation of complexes and pathways that are likely keyed to specific functional adaptations. The nuclear pore complex (NPC) contributes to many processes, including nucleocytoplasmic transport, interactions with the nuclear lamina, and mRNA processing. We exploited trypanosome parasites to investigate NPC evolution and conservation at the level of protein–protein interactions and composition. We unambiguously assigned NPC components to specific substructures and found that the NPC structural scaffold is generally conserved, albeit with lineage-specific elements. However, there is significant variation in pore membrane proteins and an absence of critical components involved in mRNA export in fungi and animals (opisthokonts). This is reflected by the completely symmetric localization of all trypanosome nucleoporins, with the exception of the nuclear basket. This architecture is highly distinct from opisthokonts. We also identify features that suggest a Ran-dependent system for mRNA export in trypanosomes, a system that may presage distinct mechanisms of protein and mRNA transport in animals and fungi. Our study highlights that shared composition of macromolecular assemblies does not necessarily equate to shared architecture. Identification of lineage-specific features within the trypanosome NPC significantly advances our understanding of mechanisms of nuclear transport, gene expression, and evolution of the nucleus.
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Jahed Z, Soheilypour M, Peyro M, Mofrad MRK. The LINC and NPC relationship – it's complicated! J Cell Sci 2016; 129:3219-29. [DOI: 10.1242/jcs.184184] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
ABSTRACT
The genetic information of eukaryotic cells is enclosed within a double-layered nuclear envelope, which comprises an inner and outer nuclear membrane. Several transmembrane proteins locate to the nuclear envelope; however, only two integral protein complexes span the nuclear envelope and connect the inside of the nucleus to the cytoplasm. The nuclear pore complex (NPC) acts as a gateway for molecular exchange between the interior of the nucleus and the cytoplasm, whereas so-called LINC complexes physically link the nucleoskeleton and the cytoskeleton. In this Commentary, we will discuss recent studies that have established direct functional associations between these two complexes. The assembly of NPCs and their even distribution throughout the nuclear envelope is dependent on components of the LINC complex. Additionally, LINC complex formation is dependent on the successful localization of inner nuclear membrane components of LINC complexes and their transport through the NPC. Furthermore, the architecture of the nuclear envelope depends on both protein complexes. Finally, we will present recent evidence showing that LINC complexes can affect nucleo-cytoplasmic transport through the NPC, further highlighting the importance of understanding the associations of these essential complexes at the nuclear envelope.
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Affiliation(s)
- Zeinab Jahed
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA
| | - Mohammad Soheilypour
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA
| | - Mohaddeseh Peyro
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA
| | - Mohammad R. K. Mofrad
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California, Berkeley, CA 94720, USA
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35
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Masuda M, Oshima A, Noguchi T, Kagiwada S. Induction of intranuclear membranes by overproduction of Opi1p and Scs2p, regulators for yeast phospholipid biosynthesis, suggests a mechanism for Opi1p nuclear translocation. J Biochem 2015; 159:351-61. [PMID: 26590299 DOI: 10.1093/jb/mvv105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/24/2015] [Indexed: 12/17/2022] Open
Abstract
In the yeast Saccharomyces cerevisiae, the expression of phospholipid biosynthetic genes is suppressed by the Opi1p negative regulator. Opi1p enters into the nucleoplasm from the nuclear membrane to suppress the gene expression under repressing conditions. The binding of Opi1p to the nuclear membrane requires an integral membrane protein, Scs2p and phosphatidic acid (PA). Although it is demonstrated that the association of Opi1p with membranes is affected by PA levels, how Opi1p dissociates from Scs2p is unknown. Here, we found that fluorescently labelled Opi1p accumulated on a perinuclear region in an Scs2p-dependent manner. Electron microscopic analyses indicated that the perinuclear region consists of intranuclear membranes, which may be formed by the invagination of the nuclear membrane due to the accumulation of Opi1p and Scs2p in a restricted area. As expected, localization of Opi1p and Scs2p in the intranuclear membranes was detected by immunoelectron microscopy. Biochemical analysis showed that Opi1p recovered in the membrane fraction was detergent insoluble while Scs2p was soluble, implying that Opi1p behaves differently from Scs2p in the fraction. We hypothesize that Opi1p dissociates from Scs2p after targeting to the nuclear membrane, making it possible to be released from the membrane quickly when PA levels decrease.
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Affiliation(s)
- Miki Masuda
- Department of Biological Sciences, Faculty of Science, Nara Women's University, Nara 630-8506, Japan
| | - Ayaka Oshima
- Department of Biological Sciences, Faculty of Science, Nara Women's University, Nara 630-8506, Japan
| | - Tetsuko Noguchi
- Department of Biological Sciences, Faculty of Science, Nara Women's University, Nara 630-8506, Japan
| | - Satoshi Kagiwada
- Department of Biological Sciences, Faculty of Science, Nara Women's University, Nara 630-8506, Japan
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36
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Mészáros N, Cibulka J, Mendiburo MJ, Romanauska A, Schneider M, Köhler A. Nuclear pore basket proteins are tethered to the nuclear envelope and can regulate membrane curvature. Dev Cell 2015; 33:285-98. [PMID: 25942622 PMCID: PMC4425464 DOI: 10.1016/j.devcel.2015.02.017] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 01/11/2015] [Accepted: 02/20/2015] [Indexed: 01/28/2023]
Abstract
Nuclear pore complexes (NPCs) are selective transport channels embedded in the nuclear envelope. The cylindrical NPC core forms a protein coat lining a highly curved membrane opening and has a basket-like structure appended to the nucleoplasmic side. How NPCs interact with lipids, promoting membrane bending and NPC integrity, is poorly understood. Here we show that the NPC basket proteins Nup1 and Nup60 directly induce membrane curvature by amphipathic helix insertion into the lipid bilayer. In a cell-free system, both Nup1 and Nup60 transform spherical liposomes into highly curved membrane structures. In vivo, high levels of the Nup1/Nup60 amphipathic helices cause deformation of the yeast nuclear membrane, whereas adjacent helical regions contribute to anchoring the basket to the NPC core. Basket amphipathic helices are functionally linked to distinct transmembrane nucleoporins of the NPC core, suggesting a key contribution to the membrane remodeling events that underlie NPC assembly. The nuclear pore basket is tethered to the nuclear envelope Amphipathic helices within Nup1 and Nup60 bind and bend membranes Basket-lipid interactions contribute to NPC integrity
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Affiliation(s)
- Noémi Mészáros
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Jakub Cibulka
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Maria Jose Mendiburo
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Anete Romanauska
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Maren Schneider
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria
| | - Alwin Köhler
- Max F. Perutz Laboratories, Medical University of Vienna, Vienna Biocenter (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria.
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37
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Souquet B, Doye V. Bending or Building: Multifaceted Functions of Amphipathic Helices in Basket Nucleoporins. Dev Cell 2015; 33:626-8. [PMID: 26102598 DOI: 10.1016/j.devcel.2015.06.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Recently reporting in Developmental Cell, Mészáros et al. (2015) and Vollmer et al. (2015) extend the inventory of membrane-binding and -bending nuclear pore proteins to peripheral nucleoporins localized at the nuclear basket.
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Affiliation(s)
- Benoit Souquet
- Institut Jacques Monod, UMR 7592 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Valérie Doye
- Institut Jacques Monod, UMR 7592 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France.
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38
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Dickmanns A, Kehlenbach RH, Fahrenkrog B. Nuclear Pore Complexes and Nucleocytoplasmic Transport: From Structure to Function to Disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 320:171-233. [PMID: 26614874 DOI: 10.1016/bs.ircmb.2015.07.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nucleocytoplasmic transport is an essential cellular activity and occurs via nuclear pore complexes (NPCs) that reside in the double membrane of the nuclear envelope. Significant progress has been made during the past few years in unravelling the ultrastructural organization of NPCs and their constituents, the nucleoporins, by cryo-electron tomography and X-ray crystallography. Mass spectrometry and genomic approaches have provided deeper insight into the specific regulation and fine tuning of individual nuclear transport pathways. Recent research has also focused on the roles nucleoporins play in health and disease, some of which go beyond nucleocytoplasmic transport. Here we review emerging results aimed at understanding NPC architecture and nucleocytoplasmic transport at the atomic level, elucidating the specific function individual nucleoporins play in nuclear trafficking, and finally lighting up the contribution of nucleoporins and nuclear transport receptors in human diseases, such as cancer and certain genetic disorders.
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Affiliation(s)
- Achim Dickmanns
- Abteilung für Molekulare Strukturbiologie, Institut für Mikrobiologie und Genetik, Göttinger Zentrum für Molekulare Biowissenschaften, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Ralph H Kehlenbach
- Department of Molecular Biology, Faculty of Medicine, Georg-August-University of Göttingen, Göttingen, Germany
| | - Birthe Fahrenkrog
- Institute of Molecular Biology and Medicine, Université Libre de Bruxelles, Charleroi, Belgium
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39
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Casey AK, Chen S, Novick P, Ferro-Novick S, Wente SR. Nuclear pore complex integrity requires Lnp1, a regulator of cortical endoplasmic reticulum. Mol Biol Cell 2015; 26:2833-44. [PMID: 26041935 PMCID: PMC4571342 DOI: 10.1091/mbc.e15-01-0053] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/21/2015] [Accepted: 05/27/2015] [Indexed: 12/31/2022] Open
Abstract
The nuclear envelope (NE) and endoplasmic reticulum (ER) are components of the same contiguous membrane system and yet have distinct cellular functions. Mounting evidence suggests roles for some ER proteins in the NE for proper nuclear pore complex (NPC) structure and function. In this study, we identify a NE role in Saccharomyces cerevisiae for Lnp1 and Sey1, proteins required for proper cortical ER formation. Both lnp1Δ and sey1Δ mutants exhibit synthetic genetic interactions with mutants in genes encoding key NPC structural components. Both Lnp1 and Sey1 physically associate with other ER components that have established NPC roles, including Rtn1, Yop1, Pom33, and Per33. Of interest, lnp1Δ rtn1Δ mutants but not rtn1Δ sey1Δ mutants exhibit defects in NPC distribution. Furthermore, the essential NPC assembly factor Ndc1 has altered interactions in the absence of Sey1. Lnp1 dimerizes in vitro via its C-terminal zinc finger motif, a property that is required for proper ER structure but not NPC integrity. These findings suggest that Lnp1's role in NPC integrity is separable from functions in the ER and is linked to Ndc1 and Rtn1 interactions.
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Affiliation(s)
- Amanda K Casey
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Shuliang Chen
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093
| | - Peter Novick
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093 Howard Hughes Medical Institute, University of California at San Diego, La Jolla, CA 92093
| | - Susan Ferro-Novick
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093
| | - Susan R Wente
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232 )
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40
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Abstract
The endosomal sorting complexes required for transport (ESCRT) are best known for their role in sorting ubiquitylated membrane proteins into endosomes. The most ancient component of the ESCRT machinery is ESCRT-III, which is capable of oligomerizing into a helical filament that drives the invagination and scission of membranes aided by the AAA ATPase, Vps4, in several additional subcellular contexts. Our recent study broadens the work of ESCRT-III by identifying its role in a quality control pathway at the nuclear envelope (NE) that ensures the normal biogenesis of nuclear pore complexes (NPCs). Here, we will elaborate on how we envision this mechanism to progress and incorporate ESCRT-III into an emerging model of nuclear pore formation. Moreover, we speculate there are additional roles for the ESCRT-III machinery at the NE that broadly function to ensure its integrity and the maintenance of the nuclear compartment.
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Key Words
- ERAD, ER-Associated Degradation
- ESCRT, Endosomal Sorting Complexes Required for Transport
- INM, Inner Nuclear Membrane
- LEM, Lap2, Emerin, MAN1
- MVB, Multivesicular Body
- NE, Nuclear Envelope
- NLS, Nuclear Localization Signal
- NPC, Nuclear Pore Complex
- ONM, Outer Nuclear Membrane
- SINC, Storage of Improperly assembled Nuclear pore Complexes
- endosomal sorting complex required for transport
- membrane curvature
- nuclear envelope
- nuclear pore complex
- quality control
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41
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Webster BM, Colombi P, Jäger J, Lusk CP. Surveillance of nuclear pore complex assembly by ESCRT-III/Vps4. Cell 2015; 159:388-401. [PMID: 25303532 DOI: 10.1016/j.cell.2014.09.012] [Citation(s) in RCA: 166] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 07/07/2014] [Accepted: 09/04/2014] [Indexed: 12/19/2022]
Abstract
The maintenance of nuclear compartmentalization by the nuclear envelope and nuclear pore complexes (NPCs) is essential for cell function; loss of compartmentalization is associated with cancers, laminopathies, and aging. We uncovered a pathway that surveils NPC assembly intermediates to promote the formation of functional NPCs. Surveillance is mediated by Heh2, a member of the LEM (Lap2-emerin-MAN1) family of integral inner nuclear membrane proteins, which binds to an early NPC assembly intermediate, but not to mature NPCs. Heh2 recruits the endosomal sorting complex required for transport (ESCRT)-III subunit Snf7 and the AAA-ATPase Vps4 to destabilize and clear defective NPC assembly intermediates. When surveillance or clearance is compromised, malformed NPCs accumulate in a storage of improperly assembled nuclear pore complexes compartment, or SINC. The SINC is retained in old mothers to prevent loss of daughter lifespan, highlighting a continuum of mechanisms to ensure nuclear compartmentalization.
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Affiliation(s)
- Brant M Webster
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Paolo Colombi
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Jens Jäger
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520, USA
| | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT 06520, USA.
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42
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Timing the window of implantation by nucleolar channel system prevalence matches the accuracy of the endometrial receptivity array. Fertil Steril 2014; 102:1477-81. [DOI: 10.1016/j.fertnstert.2014.07.1254] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 07/28/2014] [Accepted: 07/30/2014] [Indexed: 01/31/2023]
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43
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Kim SJ, Fernandez-Martinez J, Sampathkumar P, Martel A, Matsui T, Tsuruta H, Weiss TM, Shi Y, Markina-Inarrairaegui A, Bonanno JB, Sauder JM, Burley SK, Chait BT, Almo SC, Rout MP, Sali A. Integrative structure-function mapping of the nucleoporin Nup133 suggests a conserved mechanism for membrane anchoring of the nuclear pore complex. Mol Cell Proteomics 2014; 13:2911-26. [PMID: 25139911 DOI: 10.1074/mcp.m114.040915] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The nuclear pore complex (NPC) is the sole passageway for the transport of macromolecules across the nuclear envelope. Nup133, a major component in the essential Y-shaped Nup84 complex, is a large scaffold protein of the NPC's outer ring structure. Here, we describe an integrative modeling approach that produces atomic models for multiple states of Saccharomyces cerevisiae (Sc) Nup133, based on the crystal structures of the sequence segments and their homologs, including the related Vanderwaltozyma polyspora (Vp) Nup133 residues 55 to 502 (VpNup133(55-502)) determined in this study, small angle X-ray scattering profiles for 18 constructs of ScNup133 and one construct of VpNup133, and 23 negative-stain electron microscopy class averages of ScNup133(2-1157). Using our integrative approach, we then computed a multi-state structural model of the full-length ScNup133 and validated it with mutational studies and 45 chemical cross-links determined via mass spectrometry. Finally, the model of ScNup133 allowed us to annotate a potential ArfGAP1 lipid packing sensor (ALPS) motif in Sc and VpNup133 and discuss its potential significance in the context of the whole NPC; we suggest that ALPS motifs are scattered throughout the NPC's scaffold in all eukaryotes and play a major role in the assembly and membrane anchoring of the NPC in the nuclear envelope. Our results are consistent with a common evolutionary origin of Nup133 with membrane coating complexes (the protocoatomer hypothesis); the presence of the ALPS motifs in coatomer-like nucleoporins suggests an ancestral mechanism for membrane recognition present in early membrane coating complexes.
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Affiliation(s)
- Seung Joong Kim
- From the ‡Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, Byers Hall, 1700 4th Street, Suite 503B, University of California San Francisco, San Francisco, California 94158
| | - Javier Fernandez-Martinez
- ¶Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, New York 10065
| | - Parthasarathy Sampathkumar
- ‖Department of Biochemistry, Ullmann Building, Room 409, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461
| | - Anne Martel
- **Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, MS 69, Menlo Park, California 94025
| | - Tsutomu Matsui
- **Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, MS 69, Menlo Park, California 94025
| | - Hiro Tsuruta
- **Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, MS 69, Menlo Park, California 94025
| | - Thomas M Weiss
- **Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, MS 69, Menlo Park, California 94025
| | - Yi Shi
- ‡‡Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York 10065
| | - Ane Markina-Inarrairaegui
- §§Laboratorio de Genetica Molecular de Aspergillus, Departamento de Biología Celular y Molecular, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, 28040, Madrid, Spain
| | - Jeffery B Bonanno
- ‖Department of Biochemistry, Ullmann Building, Room 409, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461
| | - J Michael Sauder
- ¶¶Discovery Chemistry Research and Technologies (DCR&T), Eli Lilly and Company, Lilly Biotechnology Center, 10300 Campus Point Drive, Suite 200, San Diego, California 92121
| | - Stephen K Burley
- ‖‖Center for Integrative Proteomics Research, Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, 174 Frelinghuysen Road, Piscataway, New Jersey 08854
| | - Brian T Chait
- ‡‡Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, New York 10065
| | - Steven C Almo
- ‖Department of Biochemistry, Ullmann Building, Room 409, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461;
| | - Michael P Rout
- ¶Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, New York 10065;
| | - Andrej Sali
- From the ‡Department of Bioengineering and Therapeutic Sciences, Department of Pharmaceutical Chemistry, California Institute for Quantitative Biosciences, Byers Hall, 1700 4th Street, Suite 503B, University of California San Francisco, San Francisco, California 94158;
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44
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Bernis C, Swift-Taylor B, Nord M, Carmona S, Chook YM, Forbes DJ. Transportin acts to regulate mitotic assembly events by target binding rather than Ran sequestration. Mol Biol Cell 2014; 25:992-1009. [PMID: 24478460 PMCID: PMC3967982 DOI: 10.1091/mbc.e13-08-0506] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Transportin-specific molecular tools are used to show that the mitotic cell contains importin β and transportin “global positioning system” pathways that are mechanistically parallel. Transportin works to control where the spindle, nuclear membrane, and nuclear pores are formed by directly affecting assembly factor function. The nuclear import receptors importin β and transportin play a different role in mitosis: both act phenotypically as spatial regulators to ensure that mitotic spindle, nuclear membrane, and nuclear pore assembly occur exclusively around chromatin. Importin β is known to act by repressing assembly factors in regions distant from chromatin, whereas RanGTP produced on chromatin frees factors from importin β for localized assembly. The mechanism of transportin regulation was unknown. Diametrically opposed models for transportin action are as follows: 1) indirect action by RanGTP sequestration, thus down-regulating release of assembly factors from importin β, and 2) direct action by transportin binding and inhibiting assembly factors. Experiments in Xenopus assembly extracts with M9M, a superaffinity nuclear localization sequence that displaces cargoes bound by transportin, or TLB, a mutant transportin that can bind cargo and RanGTP simultaneously, support direct inhibition. Consistently, simple addition of M9M to mitotic cytosol induces microtubule aster assembly. ELYS and the nucleoporin 107–160 complex, components of mitotic kinetochores and nuclear pores, are blocked from binding to kinetochores in vitro by transportin, a block reversible by M9M. In vivo, 30% of M9M-transfected cells have spindle/cytokinesis defects. We conclude that the cell contains importin β and transportin “global positioning system”or “GPS” pathways that are mechanistically parallel.
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Affiliation(s)
- Cyril Bernis
- Section of Cell and Developmental Biology, Division of Biological Sciences 0347, University of California-San Diego, La Jolla, CA 92093-0347 Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9041
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Floch AG, Tareste D, Fuchs P, Chadrin A, Naciri I, Leger T, Schlenstedt G, Palancade B, Doye V. Nuclear pore targeting of the yeast Pom33 nucleoporin depends on karyopherin- and lipid-binding. J Cell Sci 2014; 128:305-16. [DOI: 10.1242/jcs.158915] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Pom33 is an integral membrane protein of the yeast nuclear pore complex (NPC), required for proper NPC distribution and assembly. To characterize Pom33 NPC-targeting determinants, we performed immunoprecipitation experiments followed by mass spectrometry analyses. This identified a novel Pom33 partner, the nuclear import factor Kap123. In vitro experiments revealed a direct interaction between Pom33 C-terminal domain (CTD) and Kap123. In silico analysis predicted the presence of two amphipathic α-helices within Pom33-CTD. Circular dichroism and liposome co-flotation assays showed that this domain is able to fold into α-helices in the presence of liposomes and preferentially binds to highly curved lipid membranes. When expressed in yeast, under conditions abolishing Pom33-CTD membrane association, this domain behaves as a Kap123-dependent nuclear localization signal (NLS). While deletion of Pom33 C-terminal domain (Pom33ΔCTD-GFP) impairs Pom33 stability and NPC targeting, mutants affecting either Kap123 binding or the amphipathic properties of the α-helices do not display any detectable defect. However, combined impairment of lipid and Kap123 binding affects Pom33 targeting to NPCs. These data highlight the requirement of multiple determinants and mechanisms for proper NPC localization of Pom33.
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Eisenhardt N, Redolfi J, Antonin W. Interaction of Nup53 with Ndc1 and Nup155 is required for nuclear pore complex assembly. J Cell Sci 2013; 127:908-21. [PMID: 24363447 DOI: 10.1242/jcs.141739] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nuclear pore complexes (NPCs) are the gateways for nucleocytoplasmic exchange. The ordered assembly of these huge complexes from several hundred individual components into an intricate protein interaction network which deforms the two membranes of the nuclear envelope into a pore is only rudimentarily understood. Here, we show that the interaction between Nup53 and the integral pore membrane protein Ndc1 is essential for vertebrate NPC assembly. The Ndc1 binding site on Nup53 overlaps with a region that induces membrane bending and is specifically required to modulate this activity, suggesting that the membrane-deforming capability of Nup53 is adjusted during the NPC assembly process. We further demonstrate that the interaction of Nup53 and Nup155 has a crucial role in NPC formation as the main determinant of recruitment of Nup155 to the assembling pore. Overall, our results pinpoint the diversity of interaction modes accomplished by Nup53, highlighting this protein as an essential link between the pore membrane and the NPC, and as a crucial factor in the formation of the pore membrane.
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Affiliation(s)
- Nathalie Eisenhardt
- Friedrich Miescher Laboratory of the Max Planck Society, Spemannstr. 39, 72076 Tübingen, Germany
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Schwartz T. Functional insights from studies on the structure of the nuclear pore and coat protein complexes. Cold Spring Harb Perspect Biol 2013; 5:cshperspect.a013375. [PMID: 23709684 DOI: 10.1101/cshperspect.a013375] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The nuclear envelope (NE) is a specific extension of the endoplasmic reticulum (ER) that wraps around the nucleus and enables the spatial separation of gene transcription and protein translation, one of the signature features of eukaryotes. Rather than being completely closed, the double lipid bilayer of the NE is perforated at sites where the inner and outer nuclear membranes fuse, resulting in circular openings lined with sharply bent membranes. These openings are filled with nuclear pore complexes (NPCs), enormous protein assemblies that facilitate nuclear transport. The scaffold components of the NPC surprisingly share interesting similarities with elements of coat protein complexes, which have general implications for function and evolution of these membrane-coating complexes. Here I discuss, from a structural perspective, what these findings might teach us.
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Affiliation(s)
- Thomas Schwartz
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
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Poring over pores: nuclear pore complex insertion into the nuclear envelope. Trends Biochem Sci 2013; 38:292-301. [DOI: 10.1016/j.tibs.2013.04.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Revised: 03/29/2013] [Accepted: 04/02/2013] [Indexed: 11/18/2022]
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Abstract
The nuclear pore complex (NPC) is the sole gateway between the nucleus and the cytoplasm. NPCs fuse the inner and outer nuclear membranes to form aqueous translocation channels that allow the free diffusion of small molecules and ions, as well as receptor-mediated transport of large macromolecules. The NPC regulates nucleocytoplasmic transport of macromolecules, utilizing soluble receptors that identify and present cargo to the NPC, in a highly selective manner to maintain cellular functions. The NPC is composed of multiple copies of approximately 30 different proteins, termed nucleoporins, which assemble to form one of the largest multiprotein assemblies in the cell. In this review, we address structural and functional aspects of this fundamental cellular machinery.
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Affiliation(s)
- Einat Grossman
- Department of Life Sciences, Ben Gurion University, Beersheva 84105, Israel
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Tarazón E, Rivera M, Roselló-Lletí E, Molina-Navarro MM, Sánchez-Lázaro IJ, España F, Montero JA, Lago F, González-Juanatey JR, Portolés M. Heart failure induces significant changes in nuclear pore complex of human cardiomyocytes. PLoS One 2012; 7:e48957. [PMID: 23152829 PMCID: PMC3495918 DOI: 10.1371/journal.pone.0048957] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 10/03/2012] [Indexed: 11/30/2022] Open
Abstract
Aims The objectives of this study were to analyse the effect of heart failure (HF) on several proteins of nuclear pore complex (NPC) and their relationship with the human ventricular function. Methods and Results A total of 88 human heart samples from ischemic (ICM, n = 52) and dilated (DCM, n = 36) patients undergoing heart transplant and control donors (CNT, n = 9) were analyzed by Western blot. Subcellular distribution of nucleoporins was analysed by fluorescence and immunocytochemistry. When we compared protein levels according to etiology, ICM showed significant higher levels of NDC1 (65%, p<0.0001), Nup160 (88%, p<0.0001) and Nup153 (137%, p = 0.004) than those of the CNT levels. Furthermore, DCM group showed significant differences for NDC1 (41%, p<0.0001), Nup160 (65%, p<0.0001), Nup153 (155%, p = 0.006) and Nup93 (88%, p<0.0001) compared with CNT. However, Nup155 and translocated promoter region (TPR) did not show significant differences in their levels in any etiology. Regarding the distribution of these proteins in cell nucleus, only NDC1 showed differences in HF. In addition, in the pathological group we obtained good relationship between the ventricular function parameters (LVEDD and LVESD) and Nup160 (r = −0382, p = 0.004; r = −0.290, p = 0.033; respectively). Conclusions This study shows alterations in specific proteins (NDC1, Nup160, Nup153 and Nup93) that compose NPC in ischaemic and dilated human heart. These changes, related to ventricular function, could be accompanied by alterations in the nucleocytoplasmic transport. Therefore, our findings may be the basis for a new approach to HF management.
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Affiliation(s)
- Estefanía Tarazón
- Cardiocirculatory Unit, Research Center, Hospital Universitario La Fe, Valencia, Spain
| | - Miguel Rivera
- Cardiocirculatory Unit, Research Center, Hospital Universitario La Fe, Valencia, Spain
| | - Esther Roselló-Lletí
- Cardiocirculatory Unit, Research Center, Hospital Universitario La Fe, Valencia, Spain
| | | | - Ignacio José Sánchez-Lázaro
- Heart Failure and Transplantation Unit, Cardiology Department, Hospital Universitario La Fe, Valencia, Spain
| | - Francisco España
- Biochemistry Unit, Research Center, Hospital Universitario La Fe, Valencia, Spain
| | | | - Francisca Lago
- Cellular and Molecular Cardiology Research Unit, Department of Cardiology and Institute of Biomedical Research, University Clinical Hospital, Santiago de Compostela, Spain
| | - José Ramón González-Juanatey
- Cellular and Molecular Cardiology Research Unit, Department of Cardiology and Institute of Biomedical Research, University Clinical Hospital, Santiago de Compostela, Spain
| | - Manuel Portolés
- Cell Biology and Pathology Unit, Research Center, Hospital Universitario La Fe, Valencia, Spain
- * E-mail:
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