1
|
Panagaki F, Tapia-Rojo R, Zhu T, Milmoe N, Paracuellos P, Board S, Mora M, Walker J, Rostkova E, Stannard A, Infante E, Garcia-Manyes S. Structural anisotropy results in mechano-directional transport of proteins across nuclear pores. NATURE PHYSICS 2024; 20:1180-1193. [PMID: 39036650 PMCID: PMC11254768 DOI: 10.1038/s41567-024-02438-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 02/08/2024] [Indexed: 07/23/2024]
Abstract
The nuclear pore complex regulates nucleocytoplasmic transport by means of a tightly synchronized suite of biochemical reactions. The physicochemical properties of the translocating cargos are emerging as master regulators of their shuttling dynamics. As well as being affected by molecular weight and surface-exposed amino acids, the kinetics of the nuclear translocation of protein cargos also depend on their nanomechanical properties, yet the mechanisms underpinning the mechanoselectivity of the nuclear pore complex are unclear. Here we show that proteins with locally soft regions in the vicinity of the nuclear-localization sequence exhibit higher nuclear-import rates, and that such mechanoselectivity is specifically impaired upon knocking down nucleoporin 153, a key protein in the nuclear pore complex. This allows us to design a short, easy-to-express and chemically inert unstructured peptide tag that accelerates the nuclear-import rate of stiff protein cargos. We also show that U2OS osteosarcoma cells expressing the peptide-tagged myocardin-related transcription factor import this mechanosensitive protein to the nucleus at higher rates and display faster motility. Locally unstructured regions lower the free-energy barrier of protein translocation and might offer a control mechanism for nuclear mechanotransduction.
Collapse
Affiliation(s)
- Fani Panagaki
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Rafael Tapia-Rojo
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Tong Zhu
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Natalie Milmoe
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Patricia Paracuellos
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Stephanie Board
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Marc Mora
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Jane Walker
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Elena Rostkova
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Andrew Stannard
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Elvira Infante
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| | - Sergi Garcia-Manyes
- Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, Centre for the Physical Science of Life and London Centre for Nanotechnology, King’s College London, London, UK
| |
Collapse
|
2
|
Zheng T, Zilman A. Kinetic cooperativity resolves bidirectional clogging within the nuclear pore complex. Biophys J 2024; 123:1085-1097. [PMID: 38640928 PMCID: PMC11079998 DOI: 10.1016/j.bpj.2024.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 12/06/2023] [Accepted: 03/22/2024] [Indexed: 04/21/2024] Open
Abstract
As the main gatekeeper of the nucleocytoplasmic transport in eukaryotic cells, the nuclear pore complex (NPC) faces the daunting task of facilitating the bidirectional transport of a high volume of macromolecular cargoes while ensuring the selectivity, speed, and efficiency of this process. The competition between opposing nuclear import and export fluxes passing through the same channel is expected to pose a major challenge to transport efficiency. It has been suggested that phase separation-like radial segregation of import and export fluxes within the assembly of intrinsically disordered proteins that line the NPC pore could be a mechanism for ensuring efficient bidirectional transport. We examine the impact of radial segregation on the efficiency of bidirectional transport through the NPC using a coarse-grained computational model of the NPC. We find little evidence that radial segregation improves transport efficiency. By contrast, surprisingly, we find that NTR crowding may enhance rather than impair the efficiency of bidirectional transport although it decreases the available space in the pore. We identify mechanisms of this novel crowding-induced transport cooperativity through the self-regulation of cargo density and flux in the pore. These findings explain how the functional architecture of the NPC resolves the problem of efficient bidirectional transport, and provide inspiration for the alleviation of clogging in artificial selective nanopores.
Collapse
Affiliation(s)
- Tiantian Zheng
- Department of Physics, University of Toronto, Toronto, ON, Canada
| | - Anton Zilman
- Department of Physics, University of Toronto, Toronto, ON, Canada.
| |
Collapse
|
3
|
Holehouse AS, Kragelund BB. The molecular basis for cellular function of intrinsically disordered protein regions. Nat Rev Mol Cell Biol 2024; 25:187-211. [PMID: 37957331 DOI: 10.1038/s41580-023-00673-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2023] [Indexed: 11/15/2023]
Abstract
Intrinsically disordered protein regions exist in a collection of dynamic interconverting conformations that lack a stable 3D structure. These regions are structurally heterogeneous, ubiquitous and found across all kingdoms of life. Despite the absence of a defined 3D structure, disordered regions are essential for cellular processes ranging from transcriptional control and cell signalling to subcellular organization. Through their conformational malleability and adaptability, disordered regions extend the repertoire of macromolecular interactions and are readily tunable by their structural and chemical context, making them ideal responders to regulatory cues. Recent work has led to major advances in understanding the link between protein sequence and conformational behaviour in disordered regions, yet the link between sequence and molecular function is less well defined. Here we consider the biochemical and biophysical foundations that underlie how and why disordered regions can engage in productive cellular functions, provide examples of emerging concepts and discuss how protein disorder contributes to intracellular information processing and regulation of cellular function.
Collapse
Affiliation(s)
- Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO, USA.
- Center for Biomolecular Condensates, Washington University in St Louis, St Louis, MO, USA.
| | - Birthe B Kragelund
- REPIN, Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
4
|
Alshareedah I, Singh A, Yang S, Ramachandran V, Quinn A, Potoyan DA, Banerjee PR. Determinants of viscoelasticity and flow activation energy in biomolecular condensates. SCIENCE ADVANCES 2024; 10:eadi6539. [PMID: 38363841 PMCID: PMC10871536 DOI: 10.1126/sciadv.adi6539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 01/17/2024] [Indexed: 02/18/2024]
Abstract
The form and function of biomolecular condensates are intimately linked to their material properties. Here, we integrate microrheology with molecular simulations to dissect the physical determinants of condensate fluid phase dynamics. By quantifying the timescales and energetics of network relaxation in a series of heterotypic viscoelastic condensates, we uncover distinctive roles of sticker motifs, binding energy, and chain length in dictating condensate dynamical properties. We find that the mechanical relaxation times of condensate-spanning networks are determined by both intermolecular interactions and chain length. We demonstrate, however, that the energy barrier for network reconfiguration, termed flow activation energy, is independent of chain length and only varies with the strengths of intermolecular interactions. Biomolecular diffusion in the dense phase depends on a complex interplay between viscoelasticity and flow activation energy. Our results illuminate distinctive roles of chain length and sequence-specific multivalent interactions underlying the complex material and transport properties of biomolecular condensates.
Collapse
Affiliation(s)
| | - Anurag Singh
- Department of Physics, University at Buffalo, Buffalo, NY 14260, USA
| | - Sean Yang
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
| | | | - Alexander Quinn
- Department of Physics, University at Buffalo, Buffalo, NY 14260, USA
| | - Davit A. Potoyan
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
| | - Priya R. Banerjee
- Department of Physics, University at Buffalo, Buffalo, NY 14260, USA
| |
Collapse
|
5
|
Fu L, Weiskopf EN, Akkermans O, Swanson NA, Cheng S, Schwartz TU, Görlich D. HIV-1 capsids enter the FG phase of nuclear pores like a transport receptor. Nature 2024; 626:843-851. [PMID: 38267583 PMCID: PMC10881386 DOI: 10.1038/s41586-023-06966-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 12/13/2023] [Indexed: 01/26/2024]
Abstract
HIV-1 infection requires nuclear entry of the viral genome. Previous evidence suggests that this entry proceeds through nuclear pore complexes (NPCs), with the 120 × 60 nm capsid squeezing through an approximately 60-nm-wide central channel1 and crossing the permeability barrier of the NPC. This barrier can be described as an FG phase2 that is assembled from cohesively interacting phenylalanine-glycine (FG) repeats3 and is selectively permeable to cargo captured by nuclear transport receptors (NTRs). Here we show that HIV-1 capsid assemblies can target NPCs efficiently in an NTR-independent manner and bind directly to several types of FG repeats, including barrier-forming cohesive repeats. Like NTRs, the capsid readily partitions into an in vitro assembled cohesive FG phase that can serve as an NPC mimic and excludes much smaller inert probes such as mCherry. Indeed, entry of the capsid protein into such an FG phase is greatly enhanced by capsid assembly, which also allows the encapsulated clients to enter. Thus, our data indicate that the HIV-1 capsid behaves like an NTR, with its interior serving as a cargo container. Because capsid-coating with trans-acting NTRs would increase the diameter by 10 nm or more, we suggest that such a 'self-translocating' capsid undermines the size restrictions imposed by the NPC scaffold, thereby bypassing an otherwise effective barrier to viral infection.
Collapse
Affiliation(s)
- Liran Fu
- Department of Cellular Logistics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Erika N Weiskopf
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Onno Akkermans
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Nicholas A Swanson
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Shiya Cheng
- Department of Meiosis, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Thomas U Schwartz
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Dirk Görlich
- Department of Cellular Logistics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
| |
Collapse
|
6
|
Rosa E Silva I, Smetana JHC, de Oliveira JF. A comprehensive review on DDX3X liquid phase condensation in health and neurodevelopmental disorders. Int J Biol Macromol 2024; 259:129330. [PMID: 38218270 DOI: 10.1016/j.ijbiomac.2024.129330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/22/2023] [Accepted: 01/06/2024] [Indexed: 01/15/2024]
Abstract
DEAD-box helicases are global regulators of liquid-liquid phase separation (LLPS), a process that assembles membraneless organelles inside cells. An outstanding member of the DEAD-box family is DDX3X, a multi-functional protein that plays critical roles in RNA metabolism, including RNA transcription, splicing, nucleocytoplasmic export, and translation. The diverse functions of DDX3X result from its ability to bind and remodel RNA in an ATP-dependent manner. This capacity enables the protein to act as an RNA chaperone and an RNA helicase, regulating ribonucleoprotein complex assembly. DDX3X and its orthologs from mouse, yeast (Ded1), and C. elegans (LAF-1) can undergo LLPS, driving the formation of neuronal granules, stress granules, processing bodies or P-granules. DDX3X has been related to several human conditions, including neurodevelopmental disorders, such as intellectual disability and autism spectrum disorder. Although the research into the pathogenesis of aberrant biomolecular condensation in neurodegenerative diseases is increasing rapidly, the role of LLPS in neurodevelopmental disorders is underexplored. This review summarizes current findings relevant for DDX3X phase separation in neurodevelopment and examines how disturbances in the LLPS process can be related to neurodevelopmental disorders.
Collapse
Affiliation(s)
- Ivan Rosa E Silva
- Brazilian Biosciences National Laboratory, Center for Research in Energy and Materials, Campinas, SP, Brazil
| | | | | |
Collapse
|
7
|
Sipko EL, Chappell GF, Berlow RB. Multivalency emerges as a common feature of intrinsically disordered protein interactions. Curr Opin Struct Biol 2024; 84:102742. [PMID: 38096754 DOI: 10.1016/j.sbi.2023.102742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/20/2023] [Accepted: 11/22/2023] [Indexed: 02/09/2024]
Abstract
Intrinsically disordered proteins (IDPs) use their unique molecular properties and conformational plasticity to interact with cellular partners in a wide variety of biological contexts. Multivalency is an important feature of IDPs that allows for utilization of an expanded toolkit for interactions with other macromolecules and confers additional complexity to molecular recognition processes. Recent studies have offered insights into how multivalent interactions of IDPs enable responsive and sensitive regulation in the context of transcription and cellular signaling. Multivalency is also widely recognized as an important feature of IDP interactions that mediate formation of biomolecular condensates. We highlight recent examples of multivalent interactions of IDPs across diverse contexts to illustrate the breadth of biological processes that utilize multivalency in molecular interactions.
Collapse
Affiliation(s)
- Emily L Sipko
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Garrett F Chappell
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rebecca B Berlow
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| |
Collapse
|
8
|
Mistriotis P, Wisniewski EO, Si BR, Kalab P, Konstantopoulos K. Coordinated in confined migration: crosstalk between the nucleus and ion channel-mediated mechanosensation. Trends Cell Biol 2024:S0962-8924(24)00001-1. [PMID: 38290913 DOI: 10.1016/j.tcb.2024.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 12/22/2023] [Accepted: 01/05/2024] [Indexed: 02/01/2024]
Abstract
Cell surface and intracellular mechanosensors enable cells to perceive different geometric, topographical, and physical cues. Mechanosensitive ion channels (MICs) localized at the cell surface and on the nuclear envelope (NE) are among the first to sense and transduce these signals. Beyond compartmentalizing the genome of the cell and its transcription, the nucleus also serves as a mechanical gauge of different physical and topographical features of the tissue microenvironment. In this review, we delve into the intricate mechanisms by which the nucleus and different ion channels regulate cell migration in confinement. We review evidence suggesting an interplay between macromolecular nuclear-cytoplasmic transport (NCT) and ionic transport across the cell membrane during confined migration. We also discuss the roles of the nucleus and ion channel-mediated mechanosensation, whether acting independently or in tandem, in orchestrating migratory mechanoresponses. Understanding nuclear and ion channel sensing, and their crosstalk, is critical to advancing our knowledge of cell migration in health and disease.
Collapse
Affiliation(s)
| | - Emily O Wisniewski
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, MD 21218, USA; Johns Hopkins Institute for NanoBioTechnology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Bishwa R Si
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, MD 21218, USA; Johns Hopkins Institute for NanoBioTechnology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Petr Kalab
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, MD 21218, USA.
| | - Konstantinos Konstantopoulos
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, MD 21218, USA; Johns Hopkins Institute for NanoBioTechnology, The Johns Hopkins University, Baltimore, MD 21218, USA; Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21218, USA; Department of Oncology, The Johns Hopkins University, Baltimore, MD 21205, USA.
| |
Collapse
|
9
|
Aksu M, Kumar P, Güttler T, Taxer W, Gregor K, Mußil B, Rymarenko O, Stegmann KM, Dickmanns A, Gerber S, Reineking W, Schulz C, Henneck T, Mohamed A, Pohlmann G, Ramazanoglu M, Mese K, Groß U, Ben-Yedidia T, Ovadia O, Fischer DW, Kamensky M, Reichman A, Baumgärtner W, von Köckritz-Blickwede M, Dobbelstein M, Görlich D. Nanobodies to multiple spike variants and inhalation of nanobody-containing aerosols neutralize SARS-CoV-2 in cell culture and hamsters. Antiviral Res 2024; 221:105778. [PMID: 38065245 DOI: 10.1016/j.antiviral.2023.105778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/23/2023] [Accepted: 12/04/2023] [Indexed: 12/17/2023]
Abstract
The ongoing threat of COVID-19 has highlighted the need for effective prophylaxis and convenient therapies, especially for outpatient settings. We have previously developed highly potent single-domain (VHH) antibodies, also known as nanobodies, that target the Receptor Binding Domain (RBD) of the SARS-CoV-2 Spike protein and neutralize the Wuhan strain of the virus. In this study, we present a new generation of anti-RBD nanobodies with superior properties. The primary representative of this group, Re32D03, neutralizes Alpha to Delta as well as Omicron BA.2.75; other members neutralize, in addition, Omicron BA.1, BA.2, BA.4/5, and XBB.1. Crystal structures of RBD-nanobody complexes reveal how ACE2-binding is blocked and also explain the nanobodies' tolerance to immune escape mutations. Through the cryo-EM structure of the Ma16B06-BA.1 Spike complex, we demonstrated how a single nanobody molecule can neutralize a trimeric spike. We also describe a method for large-scale production of these nanobodies in Pichia pastoris, and for formulating them into aerosols. Exposing hamsters to these aerosols, before or even 24 h after infection with SARS-CoV-2, significantly reduced virus load, weight loss and pathogenicity. These results show the potential of aerosolized nanobodies for prophylaxis and therapy of coronavirus infections.
Collapse
Affiliation(s)
- Metin Aksu
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany
| | - Priya Kumar
- University Medical Center Göttingen, Dept. of Molecular Oncology, Justus von Liebig Weg 11, 37077 Göttingen, Germany
| | - Thomas Güttler
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany; Octapharma Biopharmaceuticals GmbH, Im Neuenheimer Feld 590, 69120 Heidelberg, Germany
| | - Waltraud Taxer
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany
| | - Kathrin Gregor
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany
| | - Bianka Mußil
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany
| | - Oleh Rymarenko
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany
| | - Kim M Stegmann
- University Medical Center Göttingen, Dept. of Molecular Oncology, Justus von Liebig Weg 11, 37077 Göttingen, Germany
| | - Antje Dickmanns
- University Medical Center Göttingen, Dept. of Molecular Oncology, Justus von Liebig Weg 11, 37077 Göttingen, Germany
| | - Sabrina Gerber
- University Medical Center Göttingen, Dept. of Molecular Oncology, Justus von Liebig Weg 11, 37077 Göttingen, Germany
| | - Wencke Reineking
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Claudia Schulz
- Research Center for Emerging Infections and Zoonosis (RIZ), University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Timo Henneck
- Research Center for Emerging Infections and Zoonosis (RIZ), University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; Department of Biochemistry, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Ahmed Mohamed
- Research Center for Emerging Infections and Zoonosis (RIZ), University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; Department of Biochemistry, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Gerhard Pohlmann
- Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, Nikolai-Fuchs Str. 1, 30625 Hannover, Germany
| | - Mehmet Ramazanoglu
- Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, Nikolai-Fuchs Str. 1, 30625 Hannover, Germany
| | - Kemal Mese
- University Medical Center Göttingen, Dept. of Medical Microbiology and Virology, Kreuzbergring 57, 37075 Göttingen, Germany
| | - Uwe Groß
- University Medical Center Göttingen, Dept. of Medical Microbiology and Virology, Kreuzbergring 57, 37075 Göttingen, Germany
| | - Tamar Ben-Yedidia
- Scinai Immunotherapeutics Ltd., Jerusalem BioPark, Hadassah Ein Kerem, Jerusalem, 9112001, Israel
| | - Oded Ovadia
- Scinai Immunotherapeutics Ltd., Jerusalem BioPark, Hadassah Ein Kerem, Jerusalem, 9112001, Israel
| | - Dalit Weinstein Fischer
- Scinai Immunotherapeutics Ltd., Jerusalem BioPark, Hadassah Ein Kerem, Jerusalem, 9112001, Israel
| | - Merav Kamensky
- Scinai Immunotherapeutics Ltd., Jerusalem BioPark, Hadassah Ein Kerem, Jerusalem, 9112001, Israel
| | - Amir Reichman
- Scinai Immunotherapeutics Ltd., Jerusalem BioPark, Hadassah Ein Kerem, Jerusalem, 9112001, Israel
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Maren von Köckritz-Blickwede
- Research Center for Emerging Infections and Zoonosis (RIZ), University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; Department of Biochemistry, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Matthias Dobbelstein
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany; University Medical Center Göttingen, Dept. of Molecular Oncology, Justus von Liebig Weg 11, 37077 Göttingen, Germany.
| | - Dirk Görlich
- Max Planck Institute for Multidisciplinary Sciences, Dept. of Cellular Logistics, Am Fassberg 11, 37077 Göttingen, Germany.
| |
Collapse
|
10
|
Keuenhof KS, Kohler V, Broeskamp F, Panagaki D, Speese SD, Büttner S, Höög JL. Nuclear envelope budding and its cellular functions. Nucleus 2023; 14:2178184. [PMID: 36814098 PMCID: PMC9980700 DOI: 10.1080/19491034.2023.2178184] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 02/03/2023] [Indexed: 02/24/2023] Open
Abstract
The nuclear pore complex (NPC) has long been assumed to be the sole route across the nuclear envelope, and under normal homeostatic conditions it is indeed the main mechanism of nucleo-cytoplasmic transport. However, it has also been known that e.g. herpesviruses cross the nuclear envelope utilizing a pathway entitled nuclear egress or envelopment/de-envelopment. Despite this, a thread of observations suggests that mechanisms similar to viral egress may be transiently used also in healthy cells. It has since been proposed that mechanisms like nuclear envelope budding (NEB) can facilitate the transport of RNA granules, aggregated proteins, inner nuclear membrane proteins, and mis-assembled NPCs. Herein, we will summarize the known roles of NEB as a physiological and intrinsic cellular feature and highlight the many unanswered questions surrounding these intriguing nuclear events.
Collapse
Affiliation(s)
| | - Verena Kohler
- Institute of Molecular Biosciences, University of Graz, Austria
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Sweden
| | - Filomena Broeskamp
- Department for Chemistry and Molecular biology, University of Gothenburg, Sweden
| | - Dimitra Panagaki
- Department for Chemistry and Molecular biology, University of Gothenburg, Sweden
| | - Sean D. Speese
- Knight Cancer Early Detection Advanced Research Center, Oregon Health and Science University, 2720 S Moody Ave, Portland, OR, 97201, USA
| | - Sabrina Büttner
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Sweden
| | - Johanna L. Höög
- Department for Chemistry and Molecular biology, University of Gothenburg, Sweden
| |
Collapse
|
11
|
Basu S, Martínez-Cristóbal P, Frigolé-Vivas M, Pesarrodona M, Lewis M, Szulc E, Bañuelos CA, Sánchez-Zarzalejo C, Bielskutė S, Zhu J, Pombo-García K, Garcia-Cabau C, Zodi L, Dockx H, Smak J, Kaur H, Batlle C, Mateos B, Biesaga M, Escobedo A, Bardia L, Verdaguer X, Ruffoni A, Mawji NR, Wang J, Obst JK, Tam T, Brun-Heath I, Ventura S, Meierhofer D, García J, Robustelli P, Stracker TH, Sadar MD, Riera A, Hnisz D, Salvatella X. Rational optimization of a transcription factor activation domain inhibitor. Nat Struct Mol Biol 2023; 30:1958-1969. [PMID: 38049566 PMCID: PMC10716049 DOI: 10.1038/s41594-023-01159-5] [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: 11/21/2022] [Accepted: 10/23/2023] [Indexed: 12/06/2023]
Abstract
Transcription factors are among the most attractive therapeutic targets but are considered largely 'undruggable' in part due to the intrinsically disordered nature of their activation domains. Here we show that the aromatic character of the activation domain of the androgen receptor, a therapeutic target for castration-resistant prostate cancer, is key for its activity as transcription factor, allowing it to translocate to the nucleus and partition into transcriptional condensates upon activation by androgens. On the basis of our understanding of the interactions stabilizing such condensates and of the structure that the domain adopts upon condensation, we optimized the structure of a small-molecule inhibitor previously identified by phenotypic screening. The optimized compounds had more affinity for their target, inhibited androgen-receptor-dependent transcriptional programs, and had an antitumorigenic effect in models of castration-resistant prostate cancer in cells and in vivo. These results suggest that it is possible to rationally optimize, and potentially even to design, small molecules that target the activation domains of oncogenic transcription factors.
Collapse
Affiliation(s)
- Shaon Basu
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Paula Martínez-Cristóbal
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Marta Frigolé-Vivas
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Mireia Pesarrodona
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Michael Lewis
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Elzbieta Szulc
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - C Adriana Bañuelos
- Genome Sciences, BC Cancer and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Carolina Sánchez-Zarzalejo
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Stasė Bielskutė
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Jiaqi Zhu
- Dartmouth College, Department of Chemistry, Hanover, NH, USA
| | - Karina Pombo-García
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Carla Garcia-Cabau
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Levente Zodi
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | | | - Jordann Smak
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Harpreet Kaur
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Cristina Batlle
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Borja Mateos
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Mateusz Biesaga
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Albert Escobedo
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Lídia Bardia
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Xavier Verdaguer
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Departament de Química Inorgànica i Orgànica, Universitat de Barcelona, Barcelona, Spain
| | - Alessandro Ruffoni
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Nasrin R Mawji
- Genome Sciences, BC Cancer and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Jun Wang
- Genome Sciences, BC Cancer and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Jon K Obst
- Genome Sciences, BC Cancer and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Teresa Tam
- Genome Sciences, BC Cancer and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
| | - Isabelle Brun-Heath
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Salvador Ventura
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, Mass Spectrometry Facility, Berlin, Germany
| | - Jesús García
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Paul Robustelli
- Dartmouth College, Department of Chemistry, Hanover, NH, USA
| | - Travis H Stracker
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Marianne D Sadar
- Genome Sciences, BC Cancer and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada.
| | - Antoni Riera
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain.
- Departament de Química Inorgànica i Orgànica, Universitat de Barcelona, Barcelona, Spain.
| | - Denes Hnisz
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, Berlin, Germany.
| | - Xavier Salvatella
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain.
- ICREA, Barcelona, Spain.
| |
Collapse
|
12
|
Minasbekyan LA, Badalyan HG. Physical model of the nuclear membrane permeability mechanism. Biophys Rev 2023; 15:1195-1207. [PMID: 37974978 PMCID: PMC10643749 DOI: 10.1007/s12551-023-01136-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 08/31/2023] [Indexed: 11/19/2023] Open
Abstract
Nuclear cytoplasmic transport is mediated by many receptors that recognize specific nuclear localization signals on proteins and RNA and transport these substrates through nuclear pore complexes. Facilitated diffusion through nuclear pore complexes requires the attachment of transport receptors. Despite the relatively large tunnel diameter, some even small proteins (less than 20-30 kDa), such as histones, pass through the nuclear pore complex only with transport receptors. Over several decades, considerable material has been accumulated on the structure, architecture, and amino acid composition of the proteins included in this complex and the sequence of many receptors. We consider the data available in the literature on the structure of the nuclear pore complex and possible mechanisms of nuclear-cytoplasmic transport, applying the theory of electrostatic interactions in the context of our data on changes in the electrokinetic potential of nuclei and our previously proposed physical model of the mechanism of facilitated diffusion through the nuclear pore complex (NPC). According to our data, the main contribution to the charge of the nuclear membrane is made by anionic phospholipids, which are part of both the nuclear membrane and the nuclear matrix, which creates a potential difference between them. The nuclear membrane is a four-layer phospholipid dielectric, so the potential vector can only pass through the NPC, creating an electrostatic funnel that "pulls in" the positively charged load-NLS-NTR trigger complexes. Considering the newly obtained data, an improved model of the previously proposed physical model of the mechanism of nuclear-cytoplasmic transport is proposed. This model considers the contribution of electrostatic fields to the transportation speed when changing the membrane's thickness in the NPC basket at a higher load.
Collapse
Affiliation(s)
- Liya A. Minasbekyan
- Scientific Research Institute of Biology, Yerevan State University, A. Manoogian St., 1, 0025 Yerevan, Armenia
| | - Hamlet G. Badalyan
- Chair of General Physics, Yerevan State University, A. Manoogian St., 1, 0025 Yerevan, Armenia
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Minasbekyan LA, Badalyan HG. Physical model of the nuclear membrane permeability mechanism. Biophys Rev 2023; 15:1195-1207. [DOI: https:/doi.org/10.1007/s12551-023-01136-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 08/31/2023] [Indexed: 02/27/2024] Open
|
15
|
Kehlenbach RH, Neumann P, Ficner R, Dickmanns A. Interaction of nucleoporins with nuclear transport receptors: a structural perspective. Biol Chem 2023; 404:791-805. [PMID: 37210735 DOI: 10.1515/hsz-2023-0155] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 05/04/2023] [Indexed: 05/23/2023]
Abstract
Soluble nuclear transport receptors and stationary nucleoporins are at the heart of the nucleocytoplasmic transport machinery. A subset of nucleoporins contains characteristic and repetitive FG (phenylalanine-glycine) motifs, which are the basis for the permeability barrier of the nuclear pore complex (NPC) that controls transport of macromolecules between the nucleus and the cytoplasm. FG-motifs can interact with each other and/or with transport receptors, mediating their translocation across the NPC. The molecular details of homotypic and heterotypic FG-interactions have been analyzed at the structural level. In this review, we focus on the interactions of nucleoporins with nuclear transport receptors. Besides the conventional FG-motifs as interaction spots, a thorough structural analysis led us to identify additional similar motifs at the binding interface between nucleoporins and transport receptors. A detailed analysis of all known human nucleoporins revealed a large number of such phenylalanine-containing motifs that are not buried in the predicted 3D-structure of the respective protein but constitute part of the solvent-accessible surface area. Only nucleoporins that are rich in conventional FG-repeats are also enriched for these motifs. This additional layer of potential low-affinity binding sites on nucleoporins for transport receptors may have a strong impact on the interaction of transport complexes with the nuclear pore and, thus, the efficiency of nucleocytoplasmic transport.
Collapse
Affiliation(s)
- Ralph H Kehlenbach
- Department of Molecular Biology, Faculty of Medicine, GZMB, Georg-August-University Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Piotr Neumann
- Abteilung für Molekulare Strukturbiologie, Institut für Mikrobiologie und Genetik, GZMB, Georg-August-Universität Göttingen, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
| | - Ralf Ficner
- Abteilung für Molekulare Strukturbiologie, Institut für Mikrobiologie und Genetik, GZMB, Georg-August-Universität Göttingen, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
| | - Achim Dickmanns
- Abteilung für Molekulare Strukturbiologie, Institut für Mikrobiologie und Genetik, GZMB, Georg-August-Universität Göttingen, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
| |
Collapse
|
16
|
Cowburn D, Rout M. Improving the hole picture: towards a consensus on the mechanism of nuclear transport. Biochem Soc Trans 2023; 51:871-886. [PMID: 37099395 PMCID: PMC10212546 DOI: 10.1042/bst20220494] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/27/2023]
Abstract
Nuclear pore complexes (NPCs) mediate the exchange of materials between the nucleoplasm and cytoplasm, playing a key role in the separation of nucleic acids and proteins into their required compartments. The static structure of the NPC is relatively well defined by recent cryo-EM and other studies. The functional roles of dynamic components in the pore of the NPC, phenylalanyl-glycyl (FG) repeat rich nucleoporins, is less clear because of our limited understanding of highly dynamic protein systems. These proteins form a 'restrained concentrate' which interacts with and concentrates nuclear transport factors (NTRs) to provide facilitated nucleocytoplasmic transport of cargoes. Very rapid on- and off-rates among FG repeats and NTRs supports extremely fast facilitated transport, close to the rate of macromolecular diffusion in cytoplasm, while complexes without specific interactions are entropically excluded, though details on several aspects of the transport mechanism and FG repeat behaviors remain to be resolved. However, as discussed here, new technical approaches combined with more advanced modeling methods will likely provide an improved dynamic description of NPC transport, potentially at the atomic level in the near future. Such advances are likely to be of major benefit in comprehending the roles the malfunctioning NPC plays in cancer, ageing, viral diseases, and neurodegeneration.
Collapse
Affiliation(s)
- David Cowburn
- Departments of Biochemistry and Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY 10461, U.S.A
| | - Michael Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, U.S.A
| |
Collapse
|
17
|
Kozai T, Fernandez-Martinez J, van Eeuwen T, Gallardo P, Kapinos LE, Mazur A, Zhang W, Tempkin J, Panatala R, Delgado-Izquierdo M, Raveh B, Sali A, Chait BT, Veenhoff LM, Rout MP, Lim RYH. Dynamic molecular mechanism of the nuclear pore complex permeability barrier. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.31.535055. [PMID: 37066338 PMCID: PMC10103940 DOI: 10.1101/2023.03.31.535055] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Nuclear pore complexes (NPCs) mediate nucleocytoplasmic transport of specific macromolecules while impeding the exchange of unsolicited material. However, key aspects of this gating mechanism remain controversial. To address this issue, we determined the nanoscopic behavior of the permeability barrier directly within yeast S. cerevisiae NPCs at transport-relevant timescales. We show that the large intrinsically disordered domains of phenylalanine-glycine repeat nucleoporins (FG Nups) exhibit highly dynamic fluctuations to create transient voids in the permeability barrier that continuously shape-shift and reseal, resembling a radial polymer brush. Together with cargo-carrying transport factors the FG domains form a feature called the central plug, which is also highly dynamic. Remarkably, NPC mutants with longer FG domains show interweaving meshwork-like behavior that attenuates nucleocytoplasmic transport in vivo. Importantly, the bona fide nanoscale NPC behaviors and morphologies are not recapitulated by in vitro FG domain hydrogels. NPCs also exclude self-assembling FG domain condensates in vivo, thereby indicating that the permeability barrier is not generated by a self-assembling phase condensate, but rather is largely a polymer brush, organized by the NPC scaffold, whose dynamic gating selectivity is strongly enhanced by the presence of transport factors.
Collapse
Affiliation(s)
- Toshiya Kozai
- Biozentrum, University of Basel, Switzerland
- Swiss Nanoscience Institute, University of Basel, Switzerland
| | - Javier Fernandez-Martinez
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, U.S.A
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940, Leioa, Spain
| | - Trevor van Eeuwen
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, U.S.A
| | - Paola Gallardo
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, Netherlands
| | | | - Adam Mazur
- Biozentrum, University of Basel, Switzerland
| | - Wenzhu Zhang
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, U.S.A
| | - Jeremy Tempkin
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, U.S.A. Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158, USA. Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA
| | | | | | - Barak Raveh
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Israel
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, U.S.A. Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158, USA. Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Brian T. Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, U.S.A
| | - Liesbeth M. Veenhoff
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, Netherlands
| | - Michael P. Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, U.S.A
| | - Roderick Y. H. Lim
- Biozentrum, University of Basel, Switzerland
- Swiss Nanoscience Institute, University of Basel, Switzerland
| |
Collapse
|
18
|
Jibiki K, Kodama TS, Yasuhara N. Importin alpha family NAAT/IBB domain: Functions of a pleiotropic long chameleon sequence. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 134:175-209. [PMID: 36858734 DOI: 10.1016/bs.apcsb.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Nuclear transport is essential for eukaryotic cell survival and regulates the movement of functional molecules in and out of the nucleus via the nuclear pore. Transport is facilitated by protein-protein interactions between cargo and transport receptors, which contribute to the expression and regulation of downstream genetic information. This chapter focuses on the molecular basis of the multifunctional nature of the importin α family, the representative transport receptors that bring proteins into the nucleus. Importin α performs multiple functions during the nuclear transport cycle through interactions with multiple molecules by a single domain called the IBB domain. This domain is a long chameleon sequence, which can change its conformation and binding mode depending on the interaction partners. By considering the evolutionarily conserved biochemical/physicochemical propensities of the amino acids constituting the functional complex interfaces, together with their structural properties, the mechanisms of switching between multiple complexes formed via IBB and the regulation of downstream functions are examined in detail. The mechanism of regulation by IBB indicates that the time has come for a paradigm shift in the way we view the molecular mechanisms by which proteins regulate downstream functions through their interactions with other molecules.
Collapse
Affiliation(s)
- Kazuya Jibiki
- Graduate School of Integrated Basic Sciences, Nihon University, Setagaya-ku, Tokyo, Japan
| | - Takashi S Kodama
- Laboratory of Molecular Biophysics, Institute for Protein Research, Osaka University, Osaka, Japan.
| | - Noriko Yasuhara
- Graduate School of Integrated Basic Sciences, Nihon University, Setagaya-ku, Tokyo, Japan.
| |
Collapse
|
19
|
Ng SC, Biswas A, Huyton T, Schünemann J, Reber S, Görlich D. Barrier properties of Nup98 FG phases ruled by FG motif identity and inter-FG spacer length. Nat Commun 2023; 14:747. [PMID: 36765044 PMCID: PMC9918544 DOI: 10.1038/s41467-023-36331-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 01/24/2023] [Indexed: 02/12/2023] Open
Abstract
Nup98 FG repeat domains comprise hydrophobic FG motifs linked through uncharged spacers. FG motifs capture nuclear transport receptors (NTRs) during nuclear pore complex (NPC) passage, confer inter-repeat cohesion, and condense the domains into a selective phase with NPC-typical barrier properties. We show that shortening inter-FG spacers enhances cohesion, increases phase density, and tightens such barrier - all consistent with a sieve-like phase. Phase separation tolerates mutating the Nup98-typical GLFG motifs, provided domain-hydrophobicity remains preserved. NTR-entry, however, is sensitive to (certain) deviations from canonical FG motifs, suggesting co-evolutionary adaptation. Unexpectedly, we observed that arginines promote FG-phase-entry apparently also by hydrophobic interactions/ hydrogen-bonding and not just through cation-π interactions. Although incompatible with NTR·cargo complexes, a YG phase displays remarkable transport selectivity, particularly for engineered GFPNTR-variants. GLFG to FSFG mutations make the FG phase hypercohesive, precluding NTR-entry. Extending spacers relaxes this hypercohesion. Thus, antagonism between cohesion and NTR·FG interactions is key to transport selectivity.
Collapse
Affiliation(s)
- Sheung Chun Ng
- Department of Cellular Logistics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Abin Biswas
- Quantitative Biology, IRI Life Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.,Department of Biological Optomechanics, Max Planck Institute for the Science of Light, Erlangen, Germany
| | - Trevor Huyton
- Department of Cellular Logistics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Jürgen Schünemann
- Department of Cellular Logistics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Simone Reber
- Quantitative Biology, IRI Life Sciences, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dirk Görlich
- Department of Cellular Logistics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
| |
Collapse
|
20
|
Law RA, Kiepas A, Desta HE, Perez Ipiña E, Parlani M, Lee SJ, Yankaskas CL, Zhao R, Mistriotis P, Wang N, Gu Z, Kalab P, Friedl P, Camley BA, Konstantopoulos K. Cytokinesis machinery promotes cell dissociation from collectively migrating strands in confinement. SCIENCE ADVANCES 2023; 9:eabq6480. [PMID: 36630496 PMCID: PMC9833664 DOI: 10.1126/sciadv.abq6480] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Cells tune adherens junction dynamics to regulate epithelial integrity in diverse (patho)physiological processes, including cancer metastasis. We hypothesized that the spatially confining architecture of peritumor stroma promotes metastatic cell dissemination by remodeling cell-cell adhesive interactions. By combining microfluidics with live-cell imaging, FLIM/FRET biosensors, and optogenetic tools, we show that confinement induces leader cell dissociation from cohesive ensembles. Cell dissociation is triggered by myosin IIA (MIIA) dismantling of E-cadherin cell-cell junctions, as recapitulated by a mathematical model. Elevated MIIA contractility is controlled by RhoA/ROCK activation, which requires distinct guanine nucleotide exchange factors (GEFs). Confinement activates RhoA via nucleocytoplasmic shuttling of the cytokinesis-regulatory proteins RacGAP1 and Ect2 and increased microtubule dynamics, which results in the release of active GEF-H1. Thus, confining microenvironments are sufficient to induce cell dissemination from primary tumors by remodeling E-cadherin cell junctions via the interplay of microtubules, nuclear trafficking, and RhoA/ROCK/MIIA pathway and not by down-regulating E-cadherin expression.
Collapse
Affiliation(s)
- Robert A. Law
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Alexander Kiepas
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Habben E. Desta
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Emiliano Perez Ipiña
- William H. Miller III Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Maria Parlani
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Se Jong Lee
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Christopher L. Yankaskas
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Runchen Zhao
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Panagiotis Mistriotis
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Chemical Engineering, Auburn University, Auburn, AL 36849, USA
| | - Nianchao Wang
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Zhizhan Gu
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
- Corresponding author. (K.K.); (Z.G.)
| | - Petr Kalab
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Peter Friedl
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
- Cancer Genomics Center, 3584 Utrecht, Netherlands
| | - Brian A. Camley
- William H. Miller III Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Konstantinos Konstantopoulos
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Johns Hopkins Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Oncology, Johns Hopkins University, Baltimore, MD 21205, USA
- Corresponding author. (K.K.); (Z.G.)
| |
Collapse
|
21
|
van der Zanden SY, Jongsma MLM, Neefjes ACM, Berlin I, Neefjes J. Maintaining soluble protein homeostasis between nuclear and cytoplasmic compartments across mitosis. Trends Cell Biol 2023; 33:18-29. [PMID: 35778326 DOI: 10.1016/j.tcb.2022.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/23/2022] [Accepted: 06/06/2022] [Indexed: 12/27/2022]
Abstract
The nuclear envelope (NE) is central to the architecture of eukaryotic cells, both as a physical barrier separating the nucleus from the cytoplasm and as gatekeeper of selective transport between them. However, in open mitosis, the NE fragments to allow for spindle formation and segregation of chromosomes, resulting in intermixing of nuclear and cytoplasmic soluble fractions. Recent studies have shed new light on the mechanisms driving reinstatement of soluble proteome homeostasis following NE reformation in daughter cells. Here, we provide an overview of how mitotic cells confront this challenge to ensure continuity of basic cellular functions across generations and elaborate on the implications for the proteasome - a macromolecular machine that functions in both cytoplasmic and nuclear compartments.
Collapse
Affiliation(s)
- Sabina Y van der Zanden
- Department of Cell and Chemical Biology, ONCODE Institute, Leiden University Medical Center LUMC, 2333, ZC, Leiden, The Netherlands
| | - Marlieke L M Jongsma
- Department of Cell and Chemical Biology, ONCODE Institute, Leiden University Medical Center LUMC, 2333, ZC, Leiden, The Netherlands
| | - Anna C M Neefjes
- Department of Cell and Chemical Biology, ONCODE Institute, Leiden University Medical Center LUMC, 2333, ZC, Leiden, The Netherlands
| | - Ilana Berlin
- Department of Cell and Chemical Biology, ONCODE Institute, Leiden University Medical Center LUMC, 2333, ZC, Leiden, The Netherlands.
| | - Jacques Neefjes
- Department of Cell and Chemical Biology, ONCODE Institute, Leiden University Medical Center LUMC, 2333, ZC, Leiden, The Netherlands.
| |
Collapse
|
22
|
Durrieu L, Bush A, Grande A, Johansson R, Janzén D, Katz A, Cedersund G, Colman-Lerner A. Characterization of cell-to-cell variation in nuclear transport rates and identification of its sources. iScience 2022; 26:105906. [PMID: 36686393 PMCID: PMC9852351 DOI: 10.1016/j.isci.2022.105906] [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: 06/21/2022] [Revised: 11/10/2022] [Accepted: 12/25/2022] [Indexed: 12/30/2022] Open
Abstract
Nuclear transport is an essential part of eukaryotic cell function. Here, we present scFRAP, a model-assisted fluorescent recovery after photobleaching (FRAP)- based method to determine nuclear import and export rates independently in individual live cells. To overcome the inherent noise of single-cell measurements, we performed sequential FRAPs on the same cell. We found large cell-to-cell variation in transport rates within isogenic yeast populations. For passive transport, the variability in NPC number might explain most of the variability. Using this approach, we studied mother-daughter cell asymmetry in the active nuclear shuttling of the transcription factor Ace2, which is specifically concentrated in daughter cell nuclei in early G1. Rather than reduced export in the daughter cell, as previously hypothesized, we found that this asymmetry is mainly due to an increased import in daughters. These results shed light on cell-to-cell variation in cellular dynamics and its sources.
Collapse
Affiliation(s)
- Lucía Durrieu
- Department of Physiology, Molecular and Cellular Biology, School of Exact and Natural Sciences, University of Buenos Aires (UBA), C1428EGA, Argentina,Institute of Physiology, Molecular Biology and Neurosciences, National Council of Scientific and Technical Research (IFIBYNE-UBA-CONICET), C1428EGA, Argentina
| | - Alan Bush
- Department of Physiology, Molecular and Cellular Biology, School of Exact and Natural Sciences, University of Buenos Aires (UBA), C1428EGA, Argentina,Institute of Physiology, Molecular Biology and Neurosciences, National Council of Scientific and Technical Research (IFIBYNE-UBA-CONICET), C1428EGA, Argentina,Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - Alicia Grande
- Department of Physiology, Molecular and Cellular Biology, School of Exact and Natural Sciences, University of Buenos Aires (UBA), C1428EGA, Argentina,Institute of Physiology, Molecular Biology and Neurosciences, National Council of Scientific and Technical Research (IFIBYNE-UBA-CONICET), C1428EGA, Argentina
| | - Rikard Johansson
- Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - David Janzén
- Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - Andrea Katz
- Department of Physiology, Molecular and Cellular Biology, School of Exact and Natural Sciences, University of Buenos Aires (UBA), C1428EGA, Argentina
| | - Gunnar Cedersund
- Department of Biomedical Engineering, Linköping University, Linköping, Sweden
| | - Alejandro Colman-Lerner
- Department of Physiology, Molecular and Cellular Biology, School of Exact and Natural Sciences, University of Buenos Aires (UBA), C1428EGA, Argentina,Institute of Physiology, Molecular Biology and Neurosciences, National Council of Scientific and Technical Research (IFIBYNE-UBA-CONICET), C1428EGA, Argentina,Corresponding author
| |
Collapse
|
23
|
Chaperoning the nuclear envelope. Nat Cell Biol 2022; 24:1563-1564. [PMID: 36302972 DOI: 10.1038/s41556-022-01013-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
24
|
Kim JK, Han SB, Park SI, Kim IS, Kim DH. Nuclear transport of STAT6 determines the matrix rigidity dependent M2 activation of macrophages. Biomaterials 2022; 290:121859. [DOI: 10.1016/j.biomaterials.2022.121859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 10/04/2022] [Accepted: 10/09/2022] [Indexed: 11/28/2022]
|
25
|
Atypical nuclear envelope condensates linked to neurological disorders reveal nucleoporin-directed chaperone activities. Nat Cell Biol 2022; 24:1630-1641. [PMID: 36302970 PMCID: PMC10041656 DOI: 10.1038/s41556-022-01001-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 08/26/2022] [Indexed: 01/18/2023]
Abstract
DYT1 dystonia is a debilitating neurological movement disorder arising from mutation in the AAA+ ATPase TorsinA. The hallmark of Torsin dysfunction is nuclear envelope blebbing resulting from defects in nuclear pore complex biogenesis. Whether blebs actively contribute to disease manifestation is unknown. We report that FG-nucleoporins in the bleb lumen form aberrant condensates and contribute to DYT1 dystonia by provoking two proteotoxic insults. Short-lived ubiquitylated proteins that are normally rapidly degraded partition into the bleb lumen and become stabilized. In addition, blebs selectively sequester a specific HSP40-HSP70 chaperone network that is modulated by the bleb component MLF2. MLF2 suppresses the ectopic accumulation of FG-nucleoporins and modulates the selective properties and size of condensates in vitro. Our study identifies dual mechanisms of proteotoxicity in the context of condensate formation and establishes FG-nucleoporin-directed activities for a nuclear chaperone network.
Collapse
|
26
|
A simple thermodynamic description of phase separation of Nup98 FG domains. Nat Commun 2022; 13:6172. [PMID: 36257947 PMCID: PMC9579204 DOI: 10.1038/s41467-022-33697-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 09/28/2022] [Indexed: 12/24/2022] Open
Abstract
The permeability barrier of nuclear pore complexes (NPCs) controls nucleocytoplasmic transport. It retains inert macromolecules but allows facilitated passage of nuclear transport receptors that shuttle cargoes into or out of nuclei. The barrier can be described as a condensed phase assembled from cohesive FG repeat domains, including foremost the charge-depleted FG domain of Nup98. We found that Nup98 FG domains show an LCST-type phase separation, and we provide comprehensive and orthogonal experimental datasets for a quantitative description of this behaviour. A derived thermodynamic model correlates saturation concentration with repeat number, temperature, and ionic strength. It allows estimating the enthalpy, entropy, and ΔG (0.2 kJ/mol, 0.1 kB·T) contributions per repeat to phase separation and inter-repeat cohesion. While changing the cohesion strength strongly impacts the strictness of barrier, these numbers provide boundary conditions for in-depth modelling not only of barrier assembly but also of NPC passage.
Collapse
|
27
|
Takayama KI, Inoue S. Targeting phase separation on enhancers induced by transcription factor complex formations as a new strategy for treating drug-resistant cancers. Front Oncol 2022; 12:1024600. [PMID: 36263200 PMCID: PMC9574090 DOI: 10.3389/fonc.2022.1024600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 09/16/2022] [Indexed: 11/22/2022] Open
Abstract
The limited options for treating patients with drug-resistant cancers have emphasized the need to identify alternative treatment targets. Tumor cells have large super-enhancers (SEs) in the vicinity of important oncogenes for activation. The physical process of liquid-liquid phase separation (LLPS) contributes to the assembly of several membrane-less organelles in mammalian cells. Intrinsically disordered regions (IDRs) of proteins induce LLPS formation by developing condensates. It was discovered that key transcription factors (TFs) undergo LLPS in SEs. In addition, TFs play critical roles in the epigenetic and genetic regulation of cancer progression. Recently, we revealed the essential role of disease-specific TF collaboration changes in advanced prostate cancer (PC). OCT4 confers epigenetic changes by promoting complex formation with TFs, such as Forkhead box protein A1 (FOXA1), androgen receptor (AR) and Nuclear respiratory factor 1 (NRF1), inducing PC progression. It was demonstrated that TF collaboration through LLPS underlying transcriptional activation contributes to cancer aggressiveness and drug resistance. Moreover, the disruption of TF-mediated LLPS inhibited treatment-resistant PC tumor growth. Therefore, we propose that repression of TF collaborations involved in the LLPS of SEs could be a promising strategy for advanced cancer therapy. In this article, we summarize recent evidence highlighting the formation of LLPS on enhancers as a potent therapeutic target in advanced cancers.
Collapse
Affiliation(s)
- Ken-ichi Takayama
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Satoshi Inoue
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
- Division of Systems Medicine and Gene Therapy, Saitama Medical University, Saitama, Japan
- *Correspondence: Satoshi Inoue,
| |
Collapse
|
28
|
Ibáñez de Opakua A, Geraets JA, Frieg B, Dienemann C, Savastano A, Rankovic M, Cima-Omori MS, Schröder GF, Zweckstetter M. Molecular interactions of FG nucleoporin repeats at high resolution. Nat Chem 2022; 14:1278-1285. [PMID: 36138110 PMCID: PMC9630130 DOI: 10.1038/s41557-022-01035-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 08/02/2022] [Indexed: 12/01/2022]
Abstract
Proteins that contain repeat phenylalanine-glycine (FG) residues phase separate into oncogenic transcription factor condensates in malignant leukaemias, form the permeability barrier of the nuclear pore complex and mislocalize in neurodegenerative diseases. Insights into the molecular interactions of FG-repeat nucleoporins have, however, remained largely elusive. Using a combination of NMR spectroscopy and cryoelectron microscopy, we have identified uniformly spaced segments of transient β-structure and a stable preformed α-helix recognized by messenger RNA export factors in the FG-repeat domain of human nucleoporin 98 (Nup98). In addition, we have determined at high resolution the molecular organization of reversible FG–FG interactions in amyloid fibrils formed by a highly aggregation-prone segment in Nup98. We have further demonstrated that amyloid-like aggregates of the FG-repeat domain of Nup98 have low stability and are reversible. Our results provide critical insights into the molecular interactions underlying the self-association and phase separation of FG-repeat nucleoporins in physiological and pathological cell activities. ![]()
Proteins rich in phenylalanine-glycine (FG) repeats can phase separate through FG–FG interactions. The molecular interactions of an important FG-repeat protein, nucleoporin 98, have now been studied in liquid-like transient and amyloid-like cohesive states. These interactions underlie the behaviour of FG-repeat proteins and their function in physiological and pathological cell activities.
Collapse
Affiliation(s)
| | - James A Geraets
- Institute of Biological Information Processing (Structural Biochemistry), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Benedikt Frieg
- Institute of Biological Information Processing (Structural Biochemistry), Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Christian Dienemann
- Max Planck Institute for Multidisciplinary Sciences, Department of Molecular Biology, Göttingen, Germany
| | | | - Marija Rankovic
- Max Planck Institute for Multidisciplinary Sciences, Department of NMR-based Structural Biology, Göttingen, Germany
| | | | - Gunnar F Schröder
- Institute of Biological Information Processing (Structural Biochemistry), Forschungszentrum Jülich GmbH, Jülich, Germany. .,Physics Department, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases, Göttingen, Germany. .,Max Planck Institute for Multidisciplinary Sciences, Department of NMR-based Structural Biology, Göttingen, Germany.
| |
Collapse
|
29
|
Pardal AJ, Bowman AJ. A specific role for importin-5 and NASP in the import and nuclear hand-off of monomeric H3. eLife 2022; 11:e81755. [PMID: 36066346 PMCID: PMC9560165 DOI: 10.7554/elife.81755] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 09/04/2022] [Indexed: 12/04/2022] Open
Abstract
Core histones package chromosomal DNA and regulate genomic transactions, with their nuclear import and deposition involving importin-β proteins and a dedicated repertoire of histone chaperones. Previously, a histone H3-H4 dimer has been isolated bound to importin-4 (Imp4) and the chaperone ASF1, suggesting that H3 and H4 fold together in the cytoplasm before nuclear import. However, other studies have shown the existence of monomeric H3 in the nucleus, indicating a post-import folding pathway. Here, we report that the predominant importin associated with cytoplasmic H3 is importin-5 (Imp5), which hands off its monomeric cargo to nuclear sNASP. Imp5, in contrast to Imp4, binds to both H3 and H4 containing constitutively monomeric mutations and binds to newly synthesised, monomeric H3 tethered in the cytoplasm. Constitutively monomeric H3 retains its interaction with NASP, whereas monomeric H4 retains interactions specifically with HAT1 and RBBP7. High-resolution separation of NASP interactors shows the 's' isoform but not the 't' isoform associates with monomeric H3, whilst both isoforms associate with H3-H4 dimers in at least three discrete multi-chaperoning complexes. In vitro binding experiments show mutual exclusivity between sNASP and Imp5 in binding H3, suggesting direct competition for interaction sites, with the GTP-bound form of Ran required for histone transfer. Finally, using pulse-chase analysis, we show that cytoplasm-tethered histones do not interact with endogenous NASP until they reach the nucleus, whereupon they bind rapidly. We propose an Imp5-specific import pathway for monomeric H3 that hands off to sNASP in the nucleus, with a parallel H4 pathway involving Imp5 and the HAT1-RBBP7 complex, followed by nuclear folding and hand-off to deposition factors.
Collapse
Affiliation(s)
- Alonso Javier Pardal
- Division of Biomedical Sciences, Warwick Medical School, University of WarwickCoventryUnited Kingdom
| | - Andrew James Bowman
- Division of Biomedical Sciences, Warwick Medical School, University of WarwickCoventryUnited Kingdom
| |
Collapse
|
30
|
Chen M, Ma Y, Chang W. SARS-CoV-2 and the Nucleus. Int J Biol Sci 2022; 18:4731-4743. [PMID: 35874947 PMCID: PMC9305274 DOI: 10.7150/ijbs.72482] [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: 02/28/2022] [Accepted: 06/20/2022] [Indexed: 11/22/2022] Open
Abstract
The ongoing COVID-19 pandemic is caused by an RNA virus, SARS-CoV-2. The genome of SARS-CoV-2 lacks a nuclear phase in its life cycle and is replicated in the cytoplasm. However, interfering with nuclear trafficking using pharmacological inhibitors greatly reduces virus infection and virus replication of other coronaviruses is blocked in enucleated cells, suggesting a critical role of the nucleus in virus infection. Here, we summarize the alternations of nuclear pathways caused by SARS-CoV-2, including nuclear translocation pathways, innate immune responses, mRNA metabolism, epigenetic mechanisms, DNA damage response, cytoskeleton regulation, and nuclear rupture. We consider how these alternations contribute to virus replication and discuss therapeutic treatments that target these pathways, focusing on small molecule drugs that are being used in clinical studies.
Collapse
Affiliation(s)
- Mengqi Chen
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Yue Ma
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Wakam Chang
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| |
Collapse
|
31
|
Duan L, Zaepfel BL, Aksenova V, Dasso M, Rothstein JD, Kalab P, Hayes LR. Nuclear RNA binding regulates TDP-43 nuclear localization and passive nuclear export. Cell Rep 2022; 40:111106. [PMID: 35858577 PMCID: PMC9345261 DOI: 10.1016/j.celrep.2022.111106] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 03/26/2022] [Accepted: 06/27/2022] [Indexed: 11/27/2022] Open
Abstract
Nuclear clearance of the RNA-binding protein TDP-43 is a hallmark of neurodegeneration and an important therapeutic target. Our current understanding of TDP-43 nucleocytoplasmic transport does not fully explain its predominantly nuclear localization or mislocalization in disease. Here, we show that TDP-43 exits nuclei by passive diffusion, independent of facilitated mRNA export. RNA polymerase II blockade and RNase treatment induce TDP-43 nuclear efflux, suggesting that nuclear RNAs sequester TDP-43 in nuclei and limit its availability for passive export. Induction of TDP-43 nuclear efflux by short, GU-rich oligomers (presumably by outcompeting TDP-43 binding to endogenous nuclear RNAs), and nuclear retention conferred by splicing inhibition, demonstrate that nuclear TDP-43 localization depends on binding to GU-rich nuclear RNAs. Indeed, RNA-binding domain mutations markedly reduce TDP-43 nuclear localization and abolish transcription blockade-induced nuclear efflux. Thus, the nuclear abundance of GU-RNAs, dictated by the balance of transcription, pre-mRNA processing, and RNA export, regulates TDP-43 nuclear localization.
Collapse
Affiliation(s)
- Lauren Duan
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Benjamin L Zaepfel
- Biochemistry, Cellular and Molecular Biology Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Vasilisa Aksenova
- Division of Molecular and Cellular Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mary Dasso
- Division of Molecular and Cellular Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jeffrey D Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Petr Kalab
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
| | - Lindsey R Hayes
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| |
Collapse
|
32
|
Belmont AS. Nuclear Compartments: An Incomplete Primer to Nuclear Compartments, Bodies, and Genome Organization Relative to Nuclear Architecture. Cold Spring Harb Perspect Biol 2022; 14:a041268. [PMID: 34400557 PMCID: PMC9248822 DOI: 10.1101/cshperspect.a041268] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This work reviews nuclear compartments, defined broadly to include distinct nuclear structures, bodies, and chromosome domains. It first summarizes original cytological observations before comparing concepts of nuclear compartments emerging from microscopy versus genomic approaches and then introducing new multiplexed imaging approaches that promise in the future to meld both approaches. I discuss how previous models of radial distribution of chromosomes or the binary division of the genome into A and B compartments are now being refined by the recognition of more complex nuclear compartmentalization. The poorly understood question of how these nuclear compartments are established and maintained is then discussed, including through the modern perspective of phase separation, before moving on to address possible functions of nuclear compartments, using the possible role of nuclear speckles in modulating gene expression as an example. Finally, the review concludes with a discussion of future questions for this field.
Collapse
Affiliation(s)
- Andrew S Belmont
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, Illinois 61801, USA
| |
Collapse
|
33
|
Villegas JA, Levy ED. A unified statistical potential reveals that amino acid stickiness governs nonspecific recruitment of client proteins into condensates. Protein Sci 2022; 31:e4361. [PMID: 35762716 PMCID: PMC9207749 DOI: 10.1002/pro.4361] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 05/06/2022] [Accepted: 05/10/2022] [Indexed: 11/07/2022]
Abstract
Membraneless organelles are cellular compartments that form by liquid-liquid phase separation of one or more components. Other molecules, such as proteins and nucleic acids, will distribute between the cytoplasm and the liquid compartment in accordance with the thermodynamic drive to lower the free energy of the system. The resulting distribution colocalizes molecular species to carry out a diversity of functions. Two factors could drive this partitioning: the difference in solvation between the dilute versus dense phase and intermolecular interactions between the client and scaffold proteins. Here, we develop a set of knowledge-based potentials that allow for the direct comparison between stickiness, which is dominated by desolvation energy, and pairwise residue contact propensity terms. We use these scales to examine experimental data from two systems: protein cargo dissolving within phase-separated droplets made from FG repeat proteins of the nuclear pore complex and client proteins dissolving within phase-separated FUS droplets. These analyses reveal a close agreement between the stickiness of the client proteins and the experimentally determined values of the partition coefficients (R > 0.9), while pairwise residue contact propensities between client and scaffold show weaker correlations. Hence, the stickiness of client proteins is sufficient to explain their differential partitioning within these two phase-separated systems without taking into account the composition of the condensate. This result implies that selective trafficking of client proteins to distinct membraneless organelles requires recognition elements beyond the client sequence composition. STATEMENT: Empirical potentials for amino acid stickiness and pairwise residue contact propensities are derived. These scales are unique in that they enable direct comparison of desolvation versus contact terms. We find that partitioning of a client protein to a condensate is best explained by amino acid stickiness.
Collapse
Affiliation(s)
- José A. Villegas
- Department of Chemical and Structural BiologyWeizmann Institute of ScienceRehovotIsrael
- Present address:
Department of Pharmaceutical SciencesCollege of Pharmacy, University of Illinois ChicagoChicagoIL60612
| | - Emmanuel D. Levy
- Department of Chemical and Structural BiologyWeizmann Institute of ScienceRehovotIsrael
| |
Collapse
|
34
|
Andreu I, Granero-Moya I, Chahare NR, Clein K, Molina-Jordán M, Beedle AEM, Elosegui-Artola A, Abenza JF, Rossetti L, Trepat X, Raveh B, Roca-Cusachs P. Mechanical force application to the nucleus regulates nucleocytoplasmic transport. Nat Cell Biol 2022; 24:896-905. [PMID: 35681009 PMCID: PMC7614780 DOI: 10.1038/s41556-022-00927-7] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 04/26/2022] [Indexed: 12/30/2022]
Abstract
Mechanical force controls fundamental cellular processes in health and disease, and increasing evidence shows that the nucleus both experiences and senses applied forces. Such forces can lead to the nuclear translocation of proteins, but whether force controls nucleocytoplasmic transport, and how, remains unknown. Here we show that nuclear forces differentially control passive and facilitated nucleocytoplasmic transport, setting the rules for the mechanosensitivity of shuttling proteins. We demonstrate that nuclear force increases permeability across nuclear pore complexes, with a dependence on molecular weight that is stronger for passive than for facilitated diffusion. Owing to this differential effect, force leads to the translocation of cargoes into or out of the nucleus within a given range of molecular weight and affinity for nuclear transport receptors. Further, we show that the mechanosensitivity of several transcriptional regulators can be both explained by this mechanism and engineered exogenously by introducing appropriate nuclear localization signals. Our work unveils a mechanism of mechanically induced signalling, probably operating in parallel with others, with potential applicability across signalling pathways.
Collapse
Affiliation(s)
- Ion Andreu
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain.
- Universidad de Navarra, TECNUN Escuela de Ingeniería, Donostia-San Sebastián, Spain.
| | - Ignasi Granero-Moya
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
| | - Nimesh R Chahare
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Kessem Clein
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Marc Molina-Jordán
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
| | - Amy E M Beedle
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Department of Physics, King's College London, London, UK
| | - Alberto Elosegui-Artola
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Department of Physics, King's College London, London, UK
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Cell and Tissue Mechanobiology Laboratory, The Francis Crick Institute, London, UK
| | - Juan F Abenza
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Leone Rossetti
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Xavier Trepat
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - Barak Raveh
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Pere Roca-Cusachs
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain.
- Universitat de Barcelona, Barcelona, Spain.
| |
Collapse
|
35
|
Andreu I, Granero-Moya I, Garcia-Manyes S, Roca-Cusachs P. Understanding the role of mechanics in nucleocytoplasmic transport. APL Bioeng 2022; 6:020901. [PMID: 35783457 PMCID: PMC9246425 DOI: 10.1063/5.0076034] [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: 10/20/2021] [Accepted: 02/03/2022] [Indexed: 01/26/2023] Open
Abstract
Cell nuclei are submitted to mechanical forces, which in turn affect nuclear and cell functions. Recent evidence shows that a crucial mechanically regulated nuclear function is nucleocytoplasmic transport, mediated by nuclear pore complexes (NPCs). Mechanical regulation occurs at two levels: first, by force application to the nucleus, which increases NPC permeability likely through NPC stretch. Second, by the mechanical properties of the transported proteins themselves, as mechanically labile proteins translocate through NPCs faster than mechanically stiff ones. In this perspective, we discuss this evidence and the associated mechanisms by which mechanics can regulate the nucleo-cytoplasmic partitioning of proteins. Finally, we analyze how mechanical regulation of nucleocytoplasmic transport can provide a systematic approach to the study of mechanobiology and open new avenues both in fundamental and applied research.
Collapse
Affiliation(s)
- Ion Andreu
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Technology (BIST), 08028 Barcelona, Spain
| | | | - Sergi Garcia-Manyes
- Department of Physics, Randall Centre for Cell and Molecular Biophysics, King's College London, WC2R 2LS London, United Kingdom; Single Molecule Mechanobiology Laboratory, The Francis Crick Institute, NW1 1AT London, United Kingdom
| | | |
Collapse
|
36
|
Yang L, Zhang F, Chen C, Liu Z, Liu L, Li H. An Ultraviolet/Visible Light Regulated Protein Transport Gate Constructed by Pillar[6]arene-based Host-Guest System. Chem Asian J 2022; 17:e202200455. [PMID: 35532204 DOI: 10.1002/asia.202200455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/06/2022] [Indexed: 11/08/2022]
Abstract
Protein transport is an interesting and intrinsic life feature that is highly relevant to physiology and disease in living beings. Herein, inspired by nature, based on the supramolecular host-guest interaction, we have introduced the classical azobenzene light switches and L-phenylalanine derived pillar[6]arene (L-Phe-P6) into the artificial nanochannel to construct light-responsive nanochannels that could regulate protein transport effectively under the control of ultraviolet (UV) and visible (Vis) light. The light-controlled distribution of L-Phe-P6 in the channel led to the difference in surface charges in the nanochannel, which eventually brought the difference in protein transport. This research may not only provide a convenient theoretical model for biological research, but also a flexible light-responsive protein transport model, which will play a crucial role in light-controlled release of protein drugs and so on.
Collapse
Affiliation(s)
- Lei Yang
- Central China Normal University, College of Chmistry, CHINA
| | - Fan Zhang
- Hubei University, College of Chemistry and Chemical Engineering, CHINA
| | - Chunxiu Chen
- Central China Normal University, College of Chemistry, CHINA
| | - Zhisheng Liu
- Central China Normal University, College of Chemistry, CHINA
| | - Lu Liu
- Central China Normal University, College of Chemistry, CHINA
| | - Haibing Li
- Central China Normal University, Key Laboratory of Pesticide & Chemical Biology CCNU , Ministry of Education;, 152#, luoyu road, 430079, Wuhan, CHINA
| |
Collapse
|
37
|
Najbauer EE, Ng SC, Griesinger C, Görlich D, Andreas LB. Atomic resolution dynamics of cohesive interactions in phase-separated Nup98 FG domains. Nat Commun 2022; 13:1494. [PMID: 35314668 PMCID: PMC8938434 DOI: 10.1038/s41467-022-28821-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 02/09/2022] [Indexed: 01/02/2023] Open
Abstract
Cohesive FG domains assemble into a condensed phase forming the selective permeability barrier of nuclear pore complexes. Nanoscopic insight into fundamental cohesive interactions has long been hampered by the sequence heterogeneity of native FG domains. We overcome this challenge by utilizing an engineered perfectly repetitive sequence and a combination of solution and magic angle spinning NMR spectroscopy. We map the dynamics of cohesive interactions in both phase-separated and soluble states at atomic resolution using TROSY for rotational correlation time (TRACT) measurements. We find that FG repeats exhibit nanosecond-range rotational correlation times and remain disordered in both states, although FRAP measurements show slow translation of phase-separated FG domains. NOESY measurements enable the direct detection of contacts involved in cohesive interactions. Finally, increasing salt concentration and temperature enhance phase separation and decrease local mobility of FG repeats. This lower critical solution temperature (LCST) behaviour indicates that cohesive interactions are driven by entropy. The permeability barrier of nuclear pores is formed by disordered and yet self-interacting FG repeat domains, whose sequence heterogeneity is a challenge for mechanistic insights. Here the authors overcome this challenge and characterize the protein’s dynamics by applying NMR techniques to an FG phase system that has been simplified to its essentials.
Collapse
|
38
|
Di Tomaso MV, Vázquez Alberdi L, Olsson D, Cancela S, Fernández A, Rosillo JC, Reyes Ábalos AL, Álvarez Zabaleta M, Calero M, Kun A. Colocalization Analysis of Peripheral Myelin Protein-22 and Lamin-B1 in the Schwann Cell Nuclei of Wt and TrJ Mice. Biomolecules 2022; 12:456. [PMID: 35327648 PMCID: PMC8946543 DOI: 10.3390/biom12030456] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/05/2022] [Accepted: 03/12/2022] [Indexed: 12/19/2022] Open
Abstract
Myelination of the peripheral nervous system requires Schwann cells (SC) differentiation into the myelinating phenotype. The peripheral myelin protein-22 (PMP22) is an integral membrane glycoprotein, expressed in SC. It was initially described as a growth arrest-specific (gas3) gene product, up-regulated by serum starvation. PMP22 mutations were pathognomonic for human hereditary peripheral neuropathies, including the Charcot-Marie-Tooth disease (CMT). Trembler-J (TrJ) is a heterozygous mouse model carrying the same pmp22 point mutation as a CMT1E variant. Mutations in lamina genes have been related to a type of peripheral (CMT2B1) or central (autosomal dominant leukodystrophy) neuropathy. We explore the presence of PMP22 and Lamin B1 in Wt and TrJ SC nuclei of sciatic nerves and the colocalization of PMP22 concerning the silent heterochromatin (HC: DAPI-dark counterstaining), the transcriptionally active euchromatin (EC), and the nuclear lamina (H3K4m3 and Lamin B1 immunostaining, respectively). The results revealed that the number of TrJ SC nuclei in sciatic nerves was greater, and the SC volumes were smaller than those of Wt. The myelin protein PMP22 and Lamin B1 were detected in Wt and TrJ SC nuclei and predominantly in peripheral nuclear regions. The level of PMP22 was higher, and those of Lamin B1 lower in TrJ than in Wt mice. The level of PMP22 was higher, and those of Lamin B1 lower in TrJ than in Wt mice. PMP22 colocalized more with Lamin B1 and with the transcriptionally competent EC, than the silent HC with differences between Wt and TrJ genotypes. The results are discussed regarding the probable nuclear role of PMP22 and the relationship with TrJ neuropathy.
Collapse
Affiliation(s)
- María Vittoria Di Tomaso
- Departamento de Genética, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (D.O.); (S.C.); (A.L.R.Á.); (M.Á.Z.)
| | - Lucía Vázquez Alberdi
- Laboratorio de Biología Celular del Sistema Nervioso Periférico, Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay;
| | - Daniela Olsson
- Departamento de Genética, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (D.O.); (S.C.); (A.L.R.Á.); (M.Á.Z.)
| | - Saira Cancela
- Departamento de Genética, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (D.O.); (S.C.); (A.L.R.Á.); (M.Á.Z.)
| | - Anabel Fernández
- Laboratorio de Neurobiología Comparada, Departamento de Neurociencias Integrativas, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (A.F.); (J.C.R.)
| | - Juan Carlos Rosillo
- Laboratorio de Neurobiología Comparada, Departamento de Neurociencias Integrativas, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (A.F.); (J.C.R.)
| | - Ana Laura Reyes Ábalos
- Departamento de Genética, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (D.O.); (S.C.); (A.L.R.Á.); (M.Á.Z.)
- Laboratorio de Neurociencias, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Magdalena Álvarez Zabaleta
- Departamento de Genética, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay; (D.O.); (S.C.); (A.L.R.Á.); (M.Á.Z.)
| | - Miguel Calero
- Departamento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo 11800, Uruguay
- Unidad de Microscopía Electrónica de Barrido, Universidad de la República, Montevideo 11400, Uruguay
| | - Alejandra Kun
- Laboratorio de Biología Celular del Sistema Nervioso Periférico, Departamento de Proteínas y Ácidos Nucleicos, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay;
- Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Unidad de Encefalopatías Espongiformes (UFIEC), 28029 Madrid, Spain;
| |
Collapse
|
39
|
García-García M, Sánchez-Perales S, Jarabo P, Calvo E, Huyton T, Fu L, Ng SC, Sotodosos-Alonso L, Vázquez J, Casas-Tintó S, Görlich D, Echarri A, Del Pozo MA. Mechanical control of nuclear import by Importin-7 is regulated by its dominant cargo YAP. Nat Commun 2022; 13:1174. [PMID: 35246520 PMCID: PMC8897400 DOI: 10.1038/s41467-022-28693-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 01/19/2022] [Indexed: 12/31/2022] Open
Abstract
Mechanical forces regulate multiple essential pathways in the cell. The nuclear translocation of mechanoresponsive transcriptional regulators is an essential step for mechanotransduction. However, how mechanical forces regulate the nuclear import process is not understood. Here, we identify a highly mechanoresponsive nuclear transport receptor (NTR), Importin-7 (Imp7), that drives the nuclear import of YAP, a key regulator of mechanotransduction pathways. Unexpectedly, YAP governs the mechanoresponse of Imp7 by forming a YAP/Imp7 complex that responds to mechanical cues through the Hippo kinases MST1/2. Furthermore, YAP behaves as a dominant cargo of Imp7, restricting the Imp7 binding and the nuclear translocation of other Imp7 cargoes such as Smad3 and Erk2. Thus, the nuclear import process is an additional regulatory layer indirectly regulated by mechanical cues, which activate a preferential Imp7 cargo, YAP, which competes out other cargoes, resulting in signaling crosstalk. The translation of mechanical cues into gene expression changes is dependent on the nuclear import of mechanoresponsive transcriptional regulators. Here the authors identify that Importin-7 drives the nuclear import of one such regulator YAP while YAP then controls Importin-7 response to mechanical cues and restricts Importin-7 binding to other cargoes.
Collapse
Affiliation(s)
- María García-García
- Mechanoadaptation and Caveolae Biology Laboratory. Area of Cell & Developmental Biology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernández Almagro, 3, 28029, Madrid, Spain
| | - Sara Sánchez-Perales
- Mechanoadaptation and Caveolae Biology Laboratory. Area of Cell & Developmental Biology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernández Almagro, 3, 28029, Madrid, Spain
| | - Patricia Jarabo
- Instituto Cajal-CSIC, Avda. Doctor Arce, 37, 28002, Madrid, Spain
| | - Enrique Calvo
- Proteomics Unit. Area of Vascular Physiopathology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernández Almagro, 3, 28029, Madrid, Spain.,CIBER de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - Trevor Huyton
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Liran Fu
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Sheung Chun Ng
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Laura Sotodosos-Alonso
- Mechanoadaptation and Caveolae Biology Laboratory. Area of Cell & Developmental Biology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernández Almagro, 3, 28029, Madrid, Spain
| | - Jesús Vázquez
- Proteomics Unit. Area of Vascular Physiopathology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernández Almagro, 3, 28029, Madrid, Spain.,CIBER de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | | | - Dirk Görlich
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Asier Echarri
- Mechanoadaptation and Caveolae Biology Laboratory. Area of Cell & Developmental Biology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernández Almagro, 3, 28029, Madrid, Spain.
| | - Miguel A Del Pozo
- Mechanoadaptation and Caveolae Biology Laboratory. Area of Cell & Developmental Biology, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Calle Melchor Fernández Almagro, 3, 28029, Madrid, Spain.
| |
Collapse
|
40
|
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.
Collapse
Affiliation(s)
- Atsushi Matsuda
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
| | - Mohammad R. K. Mofrad
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California Berkeley, Berkeley, California 94720, USA
- Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| |
Collapse
|
41
|
Wang Z, Lou J, Zhang H. Essence determines phenomenon: Assaying the material properties of biological condensates. J Biol Chem 2022; 298:101782. [PMID: 35245500 PMCID: PMC8958544 DOI: 10.1016/j.jbc.2022.101782] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 01/02/2023] Open
Abstract
Intracellular spaces are partitioned into separate compartments to ensure that numerous biochemical reactions and cellular functions take place in a spatiotemporally controlled manner. Biomacromolecules including proteins and RNAs undergo liquid–liquid phase separation and subsequent phase transition to form biological condensates with diverse material states. The material/physical properties of biological condensates are crucial for fulfilling their distinct physiological functions, and abnormal material properties can cause deleterious effects under pathological conditions. Here, we review recent studies showing the role of the material properties of biological condensates in their physiological functions. We also summarize several classic methods as well as newly emerging techniques for characterization and/or measurement of the material properties of biological condensates.
Collapse
Affiliation(s)
- Zheng Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
| | - Jizhong Lou
- Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
| | - Hong Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; Key Laboratory of RNA Biology, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
| |
Collapse
|
42
|
Function of the Nuclear Transport Machinery in Maintaining the Distinctive Compositions of the Nucleus and Cytoplasm. Int J Mol Sci 2022; 23:ijms23052578. [PMID: 35269721 PMCID: PMC8910404 DOI: 10.3390/ijms23052578] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/13/2022] [Accepted: 02/23/2022] [Indexed: 02/06/2023] Open
Abstract
Although the separation of transcription and translation, mediated by the nuclear envelope, is the defining characteristic of Eukaryotes, the barrier between the nuclear and cytoplasmic compartments needs to be semipermeable to enable material to be moved between them. Moreover, each compartment needs to have a distinctive complement of macromolecules to mediate specific functions and so movement between them needs to be controlled. This is achieved through the selective active transport of macromolecules through the nuclear pores that stud the nuclear envelope, and which serve as a conduit between these compartments. Nuclear pores are huge cylindrical macromolecular assemblies and are constructed from the order of 30 different proteins called nucleoporins. Nuclear pores have a central transport channel that is filled with a dense network of natively unfolded portions of many different nuclear pore proteins (nucleoporins or nups). This network generates a barrier that impedes, but does not entirely prevent, the diffusion of many macromolecules through the pores. The rapid movement of a range of proteins and RNAs through the pores is mediated by a range of transport factors that bind their cargo in one compartment and release it in the other. However, although as their size increases the diffusion of macromolecules through nuclear pores is progressively impaired, additional mechanisms, including the binding of some macromolecules to immobile components of each compartment and also the active removal of macromolecules from the inappropriate compartment, are needed to fully maintain the distinctive compositions of each compartment.
Collapse
|
43
|
Musacchio A. On the role of phase separation in the biogenesis of membraneless compartments. EMBO J 2022; 41:e109952. [PMID: 35107832 PMCID: PMC8886532 DOI: 10.15252/embj.2021109952] [Citation(s) in RCA: 97] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/07/2022] [Accepted: 01/10/2022] [Indexed: 12/16/2022] Open
Abstract
Molecular mechanistic biology has ushered us into the world of life’s building blocks, revealing their interactions in macromolecular complexes and inspiring strategies for detailed functional interrogations. The biogenesis of membraneless cellular compartments, functional mesoscale subcellular locales devoid of strong internal order and delimiting membranes, is among mechanistic biology’s most demanding current challenges. A developing paradigm, biomolecular phase separation, emphasizes solvation of the building blocks through low‐affinity, weakly adhesive unspecific interactions as the driver of biogenesis of membraneless compartments. Here, I discuss the molecular underpinnings of the phase separation paradigm and demonstrate that validating its assumptions is much more challenging than hitherto appreciated. I also discuss that highly specific interactions, rather than unspecific ones, appear to be the main driver of biogenesis of subcellular compartments, while phase separation may be harnessed locally in selected instances to generate material properties tailored for specific functions, as exemplified by nucleocytoplasmic transport.
Collapse
Affiliation(s)
- Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| |
Collapse
|
44
|
Bremer A, Farag M, Borcherds WM, Peran I, Martin EW, Pappu RV, Mittag T. Deciphering how naturally occurring sequence features impact the phase behaviours of disordered prion-like domains. Nat Chem 2022; 14:196-207. [PMID: 34931046 DOI: 10.1101/2021.01.01.425046] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 10/19/2021] [Indexed: 05/25/2023]
Abstract
Prion-like low-complexity domains (PLCDs) have distinctive sequence grammars that determine their driving forces for phase separation. Here we uncover the physicochemical underpinnings of how evolutionarily conserved compositional biases influence the phase behaviour of PLCDs. We interpret our results in the context of the stickers-and-spacers model for the phase separation of associative polymers. We find that tyrosine is a stronger sticker than phenylalanine, whereas arginine is a context-dependent auxiliary sticker. In contrast, lysine weakens sticker-sticker interactions. Increasing the net charge per residue destabilizes phase separation while also weakening the strong coupling between single-chain contraction in dilute phases and multichain interactions that give rise to phase separation. Finally, glycine and serine residues act as non-equivalent spacers, and thus make the glycine versus serine contents an important determinant of the driving forces for phase separation. The totality of our results leads to a set of rules that enable comparative estimates of composition-specific driving forces for PLCD phase separation.
Collapse
Affiliation(s)
- Anne Bremer
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Mina Farag
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems (CSELS), Washington University in St Louis, St Louis, MO, USA
| | - Wade M Borcherds
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Ivan Peran
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Erik W Martin
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Rohit V Pappu
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems (CSELS), Washington University in St Louis, St Louis, MO, USA.
| | - Tanja Mittag
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA.
| |
Collapse
|
45
|
Davis LK, Ford IJ, Hoogenboom BW. Crowding-induced phase separation of nuclear transport receptors in FG nucleoporin assemblies. eLife 2022; 11:72627. [PMID: 35098921 PMCID: PMC8880993 DOI: 10.7554/elife.72627] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 01/28/2022] [Indexed: 11/13/2022] Open
Abstract
The rapid (< 1 ms) transport of biological material to and from the cell nucleus is regulated by the nuclear pore complex (NPC). At the core of the NPC is a permeability barrier consisting of intrinsically disordered Phe-Gly (FG) nucleoporins (FG Nups). Various types of nuclear transport receptors (NTRs) facilitate transport by partitioning in the FG Nup assembly, overcoming the barrier by their affinity to the FG Nups, and comprise a significant fraction of proteins in the NPC barrier. In previous work Zahn et al. (2016), we revealed a universal physical behaviour in the experimentally observed binding of two well-characterized NTRs, NTF2 and the larger Importin-β, to different planar assemblies of FG Nups, with the binding behaviour defined by negative cooperativity. This was further validated by a minimal physical model that treated the FG Nups as flexible homopolymers and the NTRs as uniformly cohesive spheres. Here, we build upon our original study by first parametrizing our model to experimental data, and next predicting the effects of crowding by different types of NTRs. We show how varying the amounts of one type of NTR modulates how the other NTR penetrates the FG Nup assembly. Notably, at similar and physiologically relevant NTR concentrations, our model predicts demixed phases of NTF2 and Imp-β within the FG Nup assembly. The functional implication of NTR phase separation is that NPCs may sustain separate transport pathways that are determined by inter-NTR competition.
Collapse
Affiliation(s)
- Luke K Davis
- Department of Physics and Astronomy, University College London, London, United Kingdom
| | - Ian J Ford
- Department of Physics and Astronomy, University College London, London, United Kingdom
| | - Bart W Hoogenboom
- London Centre for Nanotechnology, University College London, London, United Kingdom
| |
Collapse
|
46
|
Mutant libraries reveal negative design shielding proteins from supramolecular self-assembly and relocalization in cells. Proc Natl Acad Sci U S A 2022; 119:2101117119. [PMID: 35078932 PMCID: PMC8812688 DOI: 10.1073/pnas.2101117119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2021] [Indexed: 01/07/2023] Open
Abstract
Genetic mutations fuel organismal evolution but can also cause disease. As proteins are the cell’s workhorses, the ways in which mutations can disrupt their structure, stability, function, and interactions have been studied extensively. However, proteins evolve and function in a cellular context, and our ability to relate changes in protein sequence to cell-level phenotypes remains limited. In particular, the molecular mechanism underlying most disease-associated mutations is unknown. Here, we show that mutations changing a protein’s surface chemistry can dramatically impact its supramolecular self-assembly and localization in the cell. These results highlight the complex nature of genotype–phenotype relationships with a simple system. Understanding the molecular consequences of mutations in proteins is essential to map genotypes to phenotypes and interpret the increasing wealth of genomic data. While mutations are known to disrupt protein structure and function, their potential to create new structures and localization phenotypes has not yet been mapped to a sequence space. To map this relationship, we employed two homo-oligomeric protein complexes in which the internal symmetry exacerbates the impact of mutations. We mutagenized three surface residues of each complex and monitored the mutations’ effect on localization and assembly phenotypes in yeast cells. While surface mutations are classically viewed as benign, our analysis of several hundred mutants revealed they often trigger three main phenotypes in these proteins: nuclear localization, the formation of puncta, and fibers. Strikingly, more than 50% of random mutants induced one of these phenotypes in both complexes. Analyzing the mutant’s sequences showed that surface stickiness and net charge are two key physicochemical properties associated with these changes. In one complex, more than 60% of mutants self-assembled into fibers. Such a high frequency is explained by negative design: charged residues shield the complex from self-interacting with copies of itself, and the sole removal of the charges induces its supramolecular self-assembly. A subsequent analysis of several other complexes targeted with alanine mutations suggested that such negative design is common. These results highlight that minimal perturbations in protein surfaces’ physicochemical properties can frequently drive assembly and localization changes in a cellular context.
Collapse
|
47
|
Odeh HM, Fare CM, Shorter J. Nuclear-Import Receptors Counter Deleterious Phase Transitions in Neurodegenerative Disease. J Mol Biol 2022; 434:167220. [PMID: 34464655 PMCID: PMC8748273 DOI: 10.1016/j.jmb.2021.167220] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/20/2021] [Accepted: 08/24/2021] [Indexed: 01/17/2023]
Abstract
Nuclear-import receptors (NIRs) engage nuclear-localization signals (NLSs) of polypeptides in the cytoplasm and transport these cargo across the size-selective barrier of the nuclear-pore complex into the nucleoplasm. Beyond this canonical role in nuclear transport, NIRs operate in the cytoplasm to chaperone and disaggregate NLS-bearing clients. Indeed, NIRs can inhibit and reverse functional and deleterious phase transitions of their cargo, including several prominent neurodegenerative disease-linked RNA-binding proteins (RBPs) with prion-like domains (PrLDs), such as TDP-43, FUS, EWSR1, TAF15, hnRNPA1, and hnRNPA2. Importantly, elevated NIR expression can mitigate degenerative phenotypes connected to aberrant cytoplasmic aggregation of RBPs with PrLDs. Here, we review recent discoveries that NIRs can also antagonize aberrant interactions and toxicity of arginine-rich, dipeptide-repeat proteins that are associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) caused by G4C2 hexanucleotide repeat expansions in the first intron of C9ORF72. We also highlight recent findings that multiple NIR family members can prevent and reverse liquid-liquid phase separation of specific clients bearing RGG motifs in an NLS-independent manner. Finally, we discuss strategies to enhance NIR activity or expression, which could have therapeutic utility for several neurodegenerative disorders, including ALS, FTD, multisystem proteinopathy, limbic-predominant age-related TDP-43 encephalopathy, tauopathies, and related diseases.
Collapse
Affiliation(s)
- Hana M Odeh
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Charlotte M Fare
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. https://twitter.com/CharlotteFare
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
48
|
Michels JJ, Brzezinski M, Scheidt T, Lemke EA, Parekh SH. Role of Solvent Compatibility in the Phase Behavior of Binary Solutions of Weakly Associating Multivalent Polymers. Biomacromolecules 2022; 23:349-364. [PMID: 34866377 PMCID: PMC8753604 DOI: 10.1021/acs.biomac.1c01301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/23/2021] [Indexed: 11/29/2022]
Abstract
Condensate formation of biopolymer solutions, prominently those of various intrinsically disordered proteins (IDPs), is often driven by "sticky" interactions between associating residues, multivalently present along the polymer backbone. Using a ternary mean-field "stickers-and-spacers" model, we demonstrate that if sticker association is of the order of a few times the thermal energy, a delicate balance between specific binding and nonspecific polymer-solvent interactions gives rise to a particularly rich ternary phase behavior under physiological circumstances. For a generic system represented by a solution comprising multiassociative scaffold and client polymers, the difference in solvent compatibility between the polymers modulates the nature of isothermal liquid-liquid phase separation (LLPS) between associative and segregative. The calculations reveal regimes of dualistic phase behavior, where both types of LLPS occur within the same phase diagram, either associated with the presence of multiple miscibility gaps or a flip in the slope of the tie-lines belonging to a single coexistence region.
Collapse
Affiliation(s)
- Jasper J. Michels
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Mateusz Brzezinski
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Tom Scheidt
- Institute
for Molecular Biology, Johannes Gutenberg
University, Ackermannweg
4, 55128 Mainz, Germany
| | - Edward A. Lemke
- Institute
for Molecular Biology, Johannes Gutenberg
University, Ackermannweg
4, 55128 Mainz, Germany
| | - Sapun H. Parekh
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Department
of Biomedical Engineering, The University
of Texas at Austin, 107
West Dean Keeton Street Stop C0800, Austin, Texas 78712, United States
| |
Collapse
|
49
|
Lenard AJ, Hutten S, Zhou Q, Usluer S, Zhang F, Bourgeois BMR, Dormann D, Madl T. Phosphorylation Regulates CIRBP Arginine Methylation, Transportin-1 Binding and Liquid-Liquid Phase Separation. Front Mol Biosci 2021; 8:689687. [PMID: 34738012 PMCID: PMC8562343 DOI: 10.3389/fmolb.2021.689687] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 10/01/2021] [Indexed: 12/20/2022] Open
Abstract
Arginine-glycine(-glycine) (RG/RGG) regions are highly abundant in RNA-binding proteins and involved in numerous physiological processes. Aberrant liquid-liquid phase separation (LLPS) and stress granule (SGs) association of RG/RGG regions in the cytoplasm have been implicated in several neurodegenerative disorders. LLPS and SG association of these proteins is regulated by the interaction with nuclear import receptors, such as transportin-1 (TNPO1), and by post-translational arginine methylation. Strikingly, many RG/RGG proteins harbour potential phosphorylation sites within or close to their arginine methylated regions, indicating a regulatory role. Here, we studied the role of phosphorylation within RG/RGG regions on arginine methylation, TNPO1-binding and LLPS using the cold-inducible RNA-binding protein (CIRBP) as a paradigm. We show that the RG/RGG region of CIRBP is in vitro phosphorylated by serine-arginine protein kinase 1 (SRPK1), and discovered two novel phosphorylation sites in CIRBP. SRPK1-mediated phosphorylation of the CIRBP RG/RGG region impairs LLPS and binding to TNPO1 in vitro and interferes with SG association in cells. Furthermore, we uncovered that arginine methylation of the CIRBP RG/RGG region regulates in vitro phosphorylation by SRPK1. In conclusion, our findings indicate that LLPS and TNPO1-mediated chaperoning of RG/RGG proteins is regulated through an intricate interplay of post-translational modifications.
Collapse
Affiliation(s)
- Aneta J Lenard
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Saskia Hutten
- Johannes Gutenberg-Universität (JGU) Mainz, Faculty of Biology, Mainz, Germany.,BioMedical Center, Cell Biology, Ludwig-Maximilians-Universität (LMU) München, Martinsried, Germany
| | - Qishun Zhou
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Sinem Usluer
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Fangrong Zhang
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Benjamin M R Bourgeois
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Dorothee Dormann
- Johannes Gutenberg-Universität (JGU) Mainz, Faculty of Biology, Mainz, Germany.,BioMedical Center, Cell Biology, Ludwig-Maximilians-Universität (LMU) München, Martinsried, Germany.,Institute of Molecular Biology (IMB), Mainz, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Tobias Madl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| |
Collapse
|
50
|
Matsuda A, Mofrad MRK. Free energy calculations shed light on the nuclear pore complex's selective barrier nature. Biophys J 2021; 120:3628-3640. [PMID: 34339633 PMCID: PMC8456294 DOI: 10.1016/j.bpj.2021.07.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/27/2021] [Accepted: 07/27/2021] [Indexed: 12/27/2022] Open
Abstract
The nuclear pore complex (NPC) is the exclusive gateway for traffic control across the nuclear envelope. Although smaller cargoes (less than 5-9 nm in size) can freely diffuse through the NPC, the passage of larger cargoes is restricted to those accompanied by nuclear transport receptors (NTRs). This selective barrier nature of the NPC is putatively associated with the intrinsically disordered, phenylalanine-glycine repeat-domains containing nucleoporins, termed FG-Nups. The precise mechanism underlying how FG-Nups carry out such an exquisite task at high throughputs has, however, remained elusive and the subject of various hypotheses. From the thermodynamics perspective, free energy analysis can be a way to determine cargo's transportability because the traffic through the NPC must be in the direction of reducing the free energy. In this study, we developed a computational model to evaluate the free energy composed of the conformational entropy of FG-Nups and the energetic gain associated with binding interactions between FG-Nups and NTRs and investigated whether these physical features can be the basis of NPC's selectivity. Our results showed that the reduction in conformational entropy by inserting a cargo into the NPC increased the free energy by an amount substantially greater than the thermal energy (≫kBT), whereas the free energy change was negligible (
Collapse
Affiliation(s)
- Atsushi Matsuda
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California Berkeley, Berkeley, California
| | - Mohammad R K Mofrad
- Molecular Cell Biomechanics Laboratory, Departments of Bioengineering and Mechanical Engineering, University of California Berkeley, Berkeley, California; Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California.
| |
Collapse
|