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Roesmann F, Sertznig H, Klaassen K, Wilhelm A, Heininger D, Heß S, Elsner C, Marschalek R, Santiago ML, Esser S, Sutter K, Dittmer U, Widera M. The interferon-regulated host factor hnRNPA0 modulates HIV-1 production by interference with LTR activity, mRNA trafficking, and programmed ribosomal frameshifting. J Virol 2024; 98:e0053424. [PMID: 38899932 PMCID: PMC11265465 DOI: 10.1128/jvi.00534-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2024] [Accepted: 05/29/2024] [Indexed: 06/21/2024] Open
Abstract
The interplay between host factors and viral components impacts viral replication efficiency profoundly. Members of the cellular heterogeneous nuclear ribonucleoprotein family (hnRNPs) have been extensively studied as HIV-1 host dependency factors, but whether they play a role in innate immunity is currently unknown. This study aimed to identify hnRNPA0 as a type I interferon (IFN)-repressed host factor in HIV-1-infected cells. Knockdown of hnRNPA0, a situation that mirrors conditions under IFN stimulation, increased LTR activity, export of unspliced HIV-1 mRNA, viral particle production, and thus, increased infectivity. Conversely, hnRNPA0 overexpression primarily reduced plasmid-driven and integrated HIV-1 long terminal repeat (LTR) activity, significantly decreasing total viral mRNA and protein levels. In addition, high levels of hnRNPA0 significantly reduced the HIV-1 programmed ribosomal frameshifting efficiency, resulting in a shift in the HIV-1 p55/p15 ratio. The HIV-1 alternative splice site usage remained largely unaffected by altered hnRNPA0 levels suggesting that the synergistic inhibition of the LTR activity and viral mRNA transcription, as well as impaired ribosomal frameshifting efficiency, are critical factors for efficient HIV-1 replication regulated by hnRNPA0. The pleiotropic dose-dependent effects under high or low hnRNPA0 levels were further confirmed in HIV-1-infected Jurkat cells. Finally, our study revealed that hnRNPA0 levels in PBMCs were lower in therapy-naive HIV-1-infected individuals compared to healthy controls. Our findings highlight a significant role for hnRNPA0 in HIV-1 replication and suggest that its IFN-I-regulated expression levels are critical for viral fitness allowing replication in an antiviral environment.IMPORTANCERNA-binding proteins, in particular, heterogeneous nuclear ribonucleoproteins (hnRNPs), have been extensively studied. Some act as host dependency factors for HIV-1 since they are involved in multiple cellular gene expression processes. Our study revealed hnRNPA0 as an IFN-regulated host factor, that is differently expressed after IFN-I treatment in HIV-1 target cells and lower expressed in therapy-naïve HIV-1-infected individuals. Our findings demonstrate the significant pleiotropic role of hnRNPA0 in viral replication: In high concentrations, hnRNPA0 limits viral replication by negatively regulating Tat-LTR transcription, retaining unspliced mRNA in the nucleus, and significantly impairing programmed ribosomal frameshifting. Low hnRNPA0 levels as observed in IFN-treated THP-1 cells, particularly facilitate HIV LTR activity and unspliced mRNA export, suggesting a role in innate immunity in favor of HIV replication. Understanding the mode of action between hnRNPA0 and HIV-1 gene expression might help to identify novel therapeutically strategies against HIV-1 and other viruses.
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Affiliation(s)
- Fabian Roesmann
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Frankfurt, Germany
| | - Helene Sertznig
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Katleen Klaassen
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Frankfurt, Germany
| | - Alexander Wilhelm
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Frankfurt, Germany
| | - Delia Heininger
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Frankfurt, Germany
| | - Stefanie Heß
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Frankfurt, Germany
| | - Carina Elsner
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Rolf Marschalek
- Institute of Pharmaceutical Biology, Goethe-University, Frankfurt am Main, Hessen, Germany
| | - Mario L. Santiago
- Department of Medicine, University of Colorado Denver, Aurora, Colorado, USA
| | - Stefan Esser
- Institute for the Research on HIV and AIDS-associated Diseases University Hospital Essen, University Duisburg-Essen, Essen, Germany
- Department of Dermatology, HPSTD Outpatient Clinic, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Kathrin Sutter
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
- Institute for the Research on HIV and AIDS-associated Diseases University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Ulf Dittmer
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
- Institute for the Research on HIV and AIDS-associated Diseases University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Marek Widera
- Goethe University Frankfurt, University Hospital, Institute for Medical Virology, Frankfurt, Germany
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2
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Ewerling A, May-Simera HL. Evolutionary trajectory for nuclear functions of ciliary transport complex proteins. Microbiol Mol Biol Rev 2024:e0000624. [PMID: 38995044 DOI: 10.1128/mmbr.00006-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2024] Open
Abstract
SUMMARYCilia and the nucleus were two defining features of the last eukaryotic common ancestor. In early eukaryotic evolution, these structures evolved through the diversification of a common membrane-coating ancestor, the protocoatomer. While in cilia, the descendants of this protein complex evolved into parts of the intraflagellar transport complexes and BBSome, the nucleus gained its selectivity by recruiting protocoatomer-like proteins to the nuclear envelope to form the selective nuclear pore complexes. Recent studies show a growing number of proteins shared between the proteomes of the respective organelles, and it is currently unknown how ciliary transport proteins could acquire nuclear functions and vice versa. The nuclear functions of ciliary proteins are still observable today and remain relevant for the understanding of the disease mechanisms behind ciliopathies. In this work, we review the evolutionary history of cilia and nucleus and their respective defining proteins and integrate current knowledge into theories for early eukaryotic evolution. We postulate a scenario where both compartments co-evolved and that fits current models of eukaryotic evolution, explaining how ciliary proteins and nucleoporins acquired their dual functions.
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Affiliation(s)
- Alexander Ewerling
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-University, Mainz, Germany
| | - Helen Louise May-Simera
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-University, Mainz, Germany
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3
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Goswami R, Gupta A, Bednova O, Coulombe G, Patel D, Rotello VM, Leyton JV. Nuclear localization signal-tagged systems: relevant nuclear import principles in the context of current therapeutic design. Chem Soc Rev 2024; 53:204-226. [PMID: 38031452 PMCID: PMC10798298 DOI: 10.1039/d1cs00269d] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Nuclear targeting of therapeutics provides a strategy for enhancing efficacy of molecules active in the nucleus and minimizing off-target effects. 'Active' nuclear-directed transport and efficient translocations across nuclear pore complexes provide the most effective means of maximizing nuclear localization. Nuclear-targeting systems based on nuclear localization signal (NLS) motifs have progressed significantly since the beginning of the current millennium. Here, we offer a roadmap for understanding the basic mechanisms of nuclear import in the context of actionable therapeutic design for developing NLS-therapeutics with improved treatment efficacy.
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Affiliation(s)
- Ritabrita Goswami
- Department of Chemistry, University of Massachusetts, Massachusetts, USA.
| | - Aarohi Gupta
- Department of Chemistry, University of Massachusetts, Massachusetts, USA.
| | - Olga Bednova
- Département de médecine nucléaire et radiobiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Québec, Canada
| | - Gaël Coulombe
- Service des stages et du développement professionnel, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Dipika Patel
- Service des stages et du développement professionnel, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Vincent M Rotello
- Department of Chemistry, University of Massachusetts, Massachusetts, USA.
| | - Jeffrey V Leyton
- École des sciences pharmaceutiques, Université d'Ottawa, Ottawa, Ontario, Canada.
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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4
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Sharma K, Banerjee S, Savran D, Rajes C, Wiese S, Girdhar A, Schwierz N, Lee C, Shorter J, Schmidt M, Guo L, Fändrich M. Cryo-EM Structure of the Full-length hnRNPA1 Amyloid Fibril. J Mol Biol 2023; 435:168211. [PMID: 37481159 PMCID: PMC10530274 DOI: 10.1016/j.jmb.2023.168211] [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: 12/01/2022] [Revised: 07/12/2023] [Accepted: 07/14/2023] [Indexed: 07/24/2023]
Abstract
Heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) is a multifunctional RNA-binding protein that is associated with neurodegenerative diseases, such as amyotrophic lateral sclerosis and multisystem proteinopathy. In this study, we have used cryo-electron microscopy to investigate the three-dimensional structure of amyloid fibrils from full-length hnRNPA1 protein. We find that the fibril core is formed by a 45-residue segment of the prion-like low-complexity domain of the protein, whereas the remaining parts of the protein (275 residues) form a fuzzy coat around the fibril core. The fibril consists of two fibril protein stacks that are arranged into a pseudo-21 screw symmetry. The ordered core harbors several of the positions that are known to be affected by disease-associated mutations, but does not encompass the most aggregation-prone segments of the protein. These data indicate that the structures of amyloid fibrils from full-length proteins may be more complex than anticipated by current theories on protein misfolding.
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Affiliation(s)
- Kartikay Sharma
- Institute of Protein Biochemistry, Ulm University, 89081 Ulm, Germany.
| | - Sambhasan Banerjee
- Institute of Protein Biochemistry, Ulm University, 89081 Ulm, Germany. https://twitter.com/@SAMBHASANBANERJ
| | - Dilan Savran
- Dr. Senckenberg Institute of Pathology, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Cedric Rajes
- Institute of Protein Biochemistry, Ulm University, 89081 Ulm, Germany
| | - Sebastian Wiese
- Core Unit Mass Spectrometry and Proteomics, Ulm University, 89081 Ulm, Germany
| | - Amandeep Girdhar
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Nadine Schwierz
- Institute of Physics, University of Augsburg, 86159 Augsburg, Germany
| | - Christopher Lee
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. https://twitter.com/@shorterlab
| | - Matthias Schmidt
- Institute of Protein Biochemistry, Ulm University, 89081 Ulm, Germany
| | - Lin Guo
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marcus Fändrich
- Institute of Protein Biochemistry, Ulm University, 89081 Ulm, Germany
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5
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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.
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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.
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6
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Fare CM, Rhine K, Lam A, Myong S, Shorter J. A minimal construct of nuclear-import receptor Karyopherin-β2 defines the regions critical for chaperone and disaggregation activity. J Biol Chem 2023; 299:102806. [PMID: 36529289 PMCID: PMC9860449 DOI: 10.1016/j.jbc.2022.102806] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/23/2022] Open
Abstract
Karyopherin-β2 (Kapβ2) is a nuclear-import receptor that recognizes proline-tyrosine nuclear localization signals of diverse cytoplasmic cargo for transport to the nucleus. Kapβ2 cargo includes several disease-linked RNA-binding proteins with prion-like domains, such as FUS, TAF15, EWSR1, hnRNPA1, and hnRNPA2. These RNA-binding proteins with prion-like domains are linked via pathology and genetics to debilitating degenerative disorders, including amyotrophic lateral sclerosis, frontotemporal dementia, and multisystem proteinopathy. Remarkably, Kapβ2 prevents and reverses aberrant phase transitions of these cargoes, which is cytoprotective. However, the molecular determinants of Kapβ2 that enable these activities remain poorly understood, particularly from the standpoint of nuclear-import receptor architecture. Kapβ2 is a super-helical protein comprised of 20 HEAT repeats. Here, we design truncated variants of Kapβ2 and assess their ability to antagonize FUS aggregation and toxicity in yeast and FUS condensation at the pure protein level and in human cells. We find that HEAT repeats 8 to 20 of Kapβ2 recapitulate all salient features of Kapβ2 activity. By contrast, Kapβ2 truncations lacking even a single cargo-binding HEAT repeat display reduced activity. Thus, we define a minimal Kapβ2 construct for delivery in adeno-associated viruses as a potential therapeutic for amyotrophic lateral sclerosis/frontotemporal dementia, multisystem proteinopathy, and related disorders.
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Affiliation(s)
- Charlotte M Fare
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kevin Rhine
- Program in Cell, Molecular, Developmental Biology, and Biophysics, Johns Hopkins University, Baltimore, Maryland, USA; Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Andrew Lam
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Sua Myong
- Program in Cell, Molecular, Developmental Biology, and Biophysics, Johns Hopkins University, Baltimore, Maryland, USA; Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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7
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Pörschke M, Rodríguez-González I, Parfentev I, Urlaub H, Kehlenbach RH. Transportin 1 is a major nuclear import receptor of the nitric oxide synthase interacting protein. J Biol Chem 2023; 299:102932. [PMID: 36690276 PMCID: PMC9974451 DOI: 10.1016/j.jbc.2023.102932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 01/12/2023] [Accepted: 01/14/2023] [Indexed: 01/22/2023] Open
Abstract
The nitric oxide synthase interacting protein (NOSIP), an E3-ubiquitin ligase, is involved in various processes like neuronal development, craniofacial development, granulopoiesis, mitogenic signaling, apoptosis, and cell proliferation. The best-characterized function of NOSIP is the regulation of endothelial nitric oxide synthase activity by translocating the membrane-bound enzyme to the cytoskeleton, specifically in the G2 phase of the cell cycle. For this, NOSIP itself has to be translocated from its prominent localization, the nucleus, to the cytoplasm. Nuclear import of NOSIP was suggested to be mediated by the canonical transport receptors importin α/β. Recently, we found NOSIP in a proteomic screen as a potential importin 13 cargo. Here, we describe the nuclear shuttling characteristics of NOSIP in living cells and in vitro and show that it does not interact directly with importin α. Instead, it formed stable complexes with several importins (-β, -7, -β/7, -13, and transportin 1) and was also imported into the nucleus in digitonin-permeabilized cells by these factors. In living HeLa cells, transportin 1 seems to be the major nuclear import receptor for NOSIP. A detailed analysis of the NOSIP-transportin 1 interaction revealed a high affinity and an unusual binding mode, involving the N-terminal half of transportin 1. In contrast to nuclear import, nuclear export of NOSIP seems to occur mostly by passive diffusion. Thus, our results uncover additional layers in the larger process of endothelial nitric oxide synthase regulation.
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Affiliation(s)
- Marius Pörschke
- Department of Molecular Biology, Faculty of Medicine, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Inés Rodríguez-González
- Department of Molecular Biology, Faculty of Medicine, GZMB, Georg-August-University Göttingen, Göttingen, Germany
| | - Iwan Parfentev
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany,Bioanalytics Group, Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Ralph H. Kehlenbach
- Department of Molecular Biology, Faculty of Medicine, GZMB, Georg-August-University Göttingen, Göttingen, Germany,For correspondence: Ralph H. Kehlenbach
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8
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Bhattarai K, Holcik M. Diverse roles of heterogeneous nuclear ribonucleoproteins in viral life cycle. FRONTIERS IN VIROLOGY 2022. [DOI: 10.3389/fviro.2022.1044652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Understanding the host-virus interactions helps to decipher the viral replication strategies and pathogenesis. Viruses have limited genetic content and rely significantly on their host cell to establish a successful infection. Viruses depend on the host for a broad spectrum of cellular RNA-binding proteins (RBPs) throughout their life cycle. One of the major RBP families is the heterogeneous nuclear ribonucleoproteins (hnRNPs) family. hnRNPs are typically localized in the nucleus, where they are forming complexes with pre-mRNAs and contribute to many aspects of nucleic acid metabolism. hnRNPs contain RNA binding motifs and frequently function as RNA chaperones involved in pre-mRNA processing, RNA splicing, and export. Many hnRNPs shuttle between the nucleus and the cytoplasm and influence cytoplasmic processes such as mRNA stability, localization, and translation. The interactions between the hnRNPs and viral components are well-known. They are critical for processing viral nucleic acids and proteins and, therefore, impact the success of the viral infection. This review discusses the molecular mechanisms by which hnRNPs interact with and regulate each stage of the viral life cycle, such as replication, splicing, translation, and assembly of virus progeny. In addition, we expand on the role of hnRNPs in the antiviral response and as potential targets for antiviral drug research and development.
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9
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Zhai LM, Zhao Y, Xiao RL, Zhang SQ, Tian BH, Li XX, Zhang R, Ma RS, Liang HX. Nuclear-targeted carbon quantum dot mediated CRISPR/Cas9 delivery for fluorescence visualization and efficient editing. NANOSCALE 2022; 14:14645-14660. [PMID: 36165075 DOI: 10.1039/d2nr04281a] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Nuclear targeted delivery has great potential in improving the efficiency of non-viral carrier mediated genome editing. However, direct and efficient delivery of CRISPR/Cas9 plasmid into the nucleus remains a challenge. In this study, a nuclear targeted gene delivery platform based on fluorescent carbon quantum dots (CQDs) was developed. Polyethylenimine (PEI) and polyethylene glycol (PEG) synergistically passivated the surface of CQDs, providing an excitation-independent green-emitting fluorescent CQDs-PEI-PEG conjugate (CQDs-PP) with an ultra-small size and positive surface charge. Here we show that CQDs-PP could bind CRISPR/Cas9 plasmid to form a nano-complex by electrostatic attraction, which can bypass lysosomes and enter the nucleus by passive diffusion, and thereby improve the transfection efficiency. Also, CQDs-PP could deliver CRISPR/Cas9 plasmid into HeLa cells, resulting in the insertion/deletion mutation of the target EFHD1 gene. More importantly, CQDs-PP exhibited a considerably higher gene editing efficiency as well as comparable or lower cytotoxicity relative to Lipo2000 and PEI-passivated CQDs-PEI (CQDs-P). Thus, the nuclear-targeted CQDs-PP is expected to constitute an efficient CRISPR/Cas9 delivery carrier in vitro with imaging-trackable ability.
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Affiliation(s)
- Li-Min Zhai
- College of Biomedical Engineering, Taiyuan University of Technology, Jinzhong, 030600, China.
- School of Life Science, South China Normal University, Guangzhou 510631, China
| | - Yan Zhao
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, China
| | - Rui-Lin Xiao
- School of Ecology, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Shi-Quan Zhang
- College of Biomedical Engineering, Taiyuan University of Technology, Jinzhong, 030600, China.
| | - Bao-Hua Tian
- School of Ecology, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Xin-Xin Li
- School of Ecology, Taiyuan University of Technology, Taiyuan, 030024, China
| | - Rong Zhang
- Shanxi Eye Hospital Affiliated to Shanxi Medical University, Taiyuan, 030002, China
| | - Ri-Sheng Ma
- College of Biomedical Engineering, Taiyuan University of Technology, Jinzhong, 030600, China.
| | - Hai-Xia Liang
- College of Biomedical Engineering, Taiyuan University of Technology, Jinzhong, 030600, China.
- School of Ecology, Taiyuan University of Technology, Taiyuan, 030024, China
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10
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Bhattarai K, Richard T, Fatica T, Frangione B, Willmore WG, Holcik M. AMPK-related protein kinase ARK5 regulates subcellular localization of RNA-binding protein hnRNP A1 during hypertonic stress. J Biol Chem 2022; 298:102364. [PMID: 35963429 PMCID: PMC9478406 DOI: 10.1016/j.jbc.2022.102364] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 07/21/2022] [Accepted: 07/23/2022] [Indexed: 10/31/2022] Open
Abstract
The heterogeneous nuclear ribonucleoprotein hnRNP A1 is a nucleocytoplasmic-shuttling RNA-binding protein that plays an important role in nucleic acid metabolism and gene expression regulation. The function of hnRNP A1 is determined in part by its specific location within the cell. Although some work has been done to elucidate the signaling pathways that regulate the cellular localization of hnRNP A1, the precise mechanism(s), including physiological and pathophysiological conditions that alter hnRNP A1 localization, are not known. We previously conducted an unbiased RNAi-based kinome-wide screen to identify kinases that regulate hnRNP A1 localization during hypertonic stress. One of the hits from this screen is AMPK-related protein kinase 5 (ARK5). Here, we validate ARK5 as the kinase responsible for controlling hnRNP A1 subcellular localization in response to hypertonic stress. We find using immunoprecipitation and in vitro kinase assay methods that ARK5 directly interacts with and phosphorylates hnRNP A1 on serine residues within the F-peptide region. We further show that the M9 motif of hnRNP A1 is essential for the ARK5-hnRNP A1 interaction and subsequent phosphorylation. In addition, the silencing of ARK5 increases the expression of anti-apoptotic protein Bcl-xL and consequently delays caspase activation during hypertonic stress. Our results indicate that ARK5 phosphorylates hnRNP A1 and regulates its subcellular localization during hypertonic stress.
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Affiliation(s)
- Krishna Bhattarai
- Department of Health Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Travis Richard
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Thet Fatica
- Department of Health Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | - Brianna Frangione
- Department of Health Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada
| | | | - Martin Holcik
- Department of Health Sciences, Carleton University, Ottawa, ON, K1S 5B6, Canada.
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11
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Li X, Kuang Y, Ye Y, Chen Z, Zhang M. Diverse function of the PISTILLATA, APETALA 3, and AGAMOUS-like MADS-box genes involved in the floral development in Alpinia hainanensis (Zingiberaceae). Gene X 2022; 839:146732. [PMID: 35840006 DOI: 10.1016/j.gene.2022.146732] [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: 11/10/2021] [Revised: 06/23/2022] [Accepted: 07/08/2022] [Indexed: 11/25/2022] Open
Abstract
Zingiberaceae is the vital clue and key node in the decreased process of fertile stamens in Zingiberales, helping to understand the evolution of the ginger families. This study focuses on Alpinia hainanensis to investigate the function of B- and C-class MADS-box genes in floral development. The introns size of two B-class genes AhPI and AhAP3, and one C-class gene AhAG are quite variable. By contrast, the positions of the corresponding introns are conserved, resulting in a similar exon size in homologs. The typical region 70 bp-CCAATCA element was not found in the second intron of AhAG compared to AG homologs. The subcellular localization showed that AhAP3 was in both intranuclear and extranuclear. The heterodimer was formed between APETALA3 and PISTILLATA but not between the B- and C-class proteins using Y2H and BiFC. The 35S::AhAG heterologous transformed Arabidopsis had curly and smaller rosette leaves with early flowering. Floral organs had no homeotic conversion, albeit sepals and petals reduced in size. Siliques development was affected and displayed wrinkled and shorter. By contrast, 35S::AhAP3 and 35S::AhPI did not show any modified phenotype in transgenic Arabidopsis thaliana. We first proposed the model for Alpinia flower development. MADS-box transcription factor binding at particular genomic locations and interaction with partners may be crucial for the development of the floral organ.
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Affiliation(s)
- Xiumei Li
- Guangdong Provincial Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
| | - Yanfeng Kuang
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
| | - Yushi Ye
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
| | - Zhongjian Chen
- Guangdong Provincial Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Agro-biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
| | - Mingyong Zhang
- Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
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12
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Kim HJ, Mohassel P, Donkervoort S, Guo L, O'Donovan K, Coughlin M, Lornage X, Foulds N, Hammans SR, Foley AR, Fare CM, Ford AF, Ogasawara M, Sato A, Iida A, Munot P, Ambegaonkar G, Phadke R, O'Donovan DG, Buchert R, Grimmel M, Töpf A, Zaharieva IT, Brady L, Hu Y, Lloyd TE, Klein A, Steinlin M, Kuster A, Mercier S, Marcorelles P, Péréon Y, Fleurence E, Manzur A, Ennis S, Upstill-Goddard R, Bello L, Bertolin C, Pegoraro E, Salviati L, French CE, Shatillo A, Raymond FL, Haack TB, Quijano-Roy S, Böhm J, Nelson I, Stojkovic T, Evangelista T, Straub V, Romero NB, Laporte J, Muntoni F, Nishino I, Tarnopolsky MA, Shorter J, Bönnemann CG, Taylor JP. Heterozygous frameshift variants in HNRNPA2B1 cause early-onset oculopharyngeal muscular dystrophy. Nat Commun 2022; 13:2306. [PMID: 35484142 PMCID: PMC9050844 DOI: 10.1038/s41467-022-30015-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 03/25/2022] [Indexed: 01/05/2023] Open
Abstract
Missense variants in RNA-binding proteins (RBPs) underlie a spectrum of disease phenotypes, including amyotrophic lateral sclerosis, frontotemporal dementia, and inclusion body myopathy. Here, we present ten independent families with a severe, progressive muscular dystrophy, reminiscent of oculopharyngeal muscular dystrophy (OPMD) but of much earlier onset, caused by heterozygous frameshift variants in the RBP hnRNPA2/B1. All disease-causing frameshift mutations abolish the native stop codon and extend the reading frame, creating novel transcripts that escape nonsense-mediated decay and are translated to produce hnRNPA2/B1 protein with the same neomorphic C-terminal sequence. In contrast to previously reported disease-causing missense variants in HNRNPA2B1, these frameshift variants do not increase the propensity of hnRNPA2 protein to fibrillize. Rather, the frameshift variants have reduced affinity for the nuclear import receptor karyopherin β2, resulting in cytoplasmic accumulation of hnRNPA2 protein in cells and in animal models that recapitulate the human pathology. Thus, we expand the phenotypes associated with HNRNPA2B1 to include an early-onset form of OPMD caused by frameshift variants that alter its nucleocytoplasmic transport dynamics.
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Affiliation(s)
- Hong Joo Kim
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Payam Mohassel
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Sandra Donkervoort
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Lin Guo
- Department of Biochemistry & Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, United States
| | - Kevin O'Donovan
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Maura Coughlin
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, United States
| | - Xaviere Lornage
- Département Médecine Translationnelle et Neurogénétique, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Institut National de la Santé et de la Recherche Médicale U1258, Centre National de la Recherche Scientifique UMR7104, Université de Strasbourg, Illkirch, France
| | - Nicola Foulds
- Wessex Clinical Genetics Services, Princess Anne Hospital, Academic Unit of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, England
| | - Simon R Hammans
- Wessex Neurological Centre, University Hospital Southampton, Southampton, UK
| | - A Reghan Foley
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Charlotte M Fare
- Department of Biochemistry & Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States
| | - Alice F Ford
- Department of Biochemistry & Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States
| | - Masashi Ogasawara
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), 4-1-1 Ogawahigashi, Kodaira, Tokyo, 187-8502, Japan
- Medical Genome Center, NCNP, Kodaira, Tokyo, Japan
| | - Aki Sato
- Department of Neurology, Niigata City General Hospital, Niigata, Japan
| | | | - Pinki Munot
- The Dubowitz Neuromuscular Centre, NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, & Great Ormond Street Hospital Trust, London, UK
| | - Gautam Ambegaonkar
- Department of Paediatric Neurology, Cambridge University Hospital NHS Trust, Addenbrookes Hospital, Cambridge, CB2 0QQ, UK
| | - Rahul Phadke
- Division of Neuropathology, University College London Hospitals NHS Foundation Trust National Hospital for Neurology and Neurosurgery London, UK and Division of Neuropathology, UCL Institute of Neurology, Dubowitz Neuromuscular Centre, London, UK
| | - Dominic G O'Donovan
- Department of Histopathology Box 235, Level 5 John Bonnett Clinical Laboratories Addenbrooke's Hospital, Cambridge, UK
| | - Rebecca Buchert
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany
| | - Mona Grimmel
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany
| | - Ana Töpf
- John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Irina T Zaharieva
- The Dubowitz Neuromuscular Centre, NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, & Great Ormond Street Hospital Trust, London, UK
| | - Lauren Brady
- Division of Neuromuscular & Neurometabolic Disorders, Department of Pediatrics, McMaster University, Hamilton Health Sciences Centre, Hamilton, ON, Canada
| | - Ying Hu
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Thomas E Lloyd
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Andrea Klein
- Division of Neuropaediatrics, Development and Rehabilitation, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Pediatric Neurology, University Children's Hospital Basel, University of Basel, Basel, Switzerland
| | - Maja Steinlin
- Division of Neuropaediatrics, Development and Rehabilitation, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Alice Kuster
- Department of Neurometabolism, University Hospital of Nantes, Nantes, France
| | - Sandra Mercier
- CHU Nantes, Service de génétique médicale, Centre de Référence des Maladies Neuromusculaires AOC, 44000, Nantes, France
- Université de Nantes, CNRS, INSERM, l'institut du thorax, 44000, Nantes, France
| | - Pascale Marcorelles
- Service d'anatomopathologie, CHU Brest and EA 4685 LIEN, Université de Bretagne Occidentale, Brest, France
| | - Yann Péréon
- CHU de Nantes, Centre de Référence des Maladies Neuromusculaires, Filnemus, Euro-NMD, Hôtel-Dieu, Nantes, France
| | - Emmanuelle Fleurence
- Etablissement de Santé pour Enfants et Adolescents de la région Nantaise, Nantes, France
| | - Adnan Manzur
- The Dubowitz Neuromuscular Centre, NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, & Great Ormond Street Hospital Trust, London, UK
| | - Sarah Ennis
- Human Genetics and Genomic Medicine, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Rosanna Upstill-Goddard
- Human Genetics and Genomic Medicine, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Luca Bello
- Department of Neurosciences, DNS, University of Padova, Padova, Italy
| | - Cinzia Bertolin
- Clinical Genetics Unit, Department of Women and Children's Health, University of Padova, IRP Città della Speranza, Padova, Italy
| | - Elena Pegoraro
- Department of Neurosciences, DNS, University of Padova, Padova, Italy
| | - Leonardo Salviati
- Clinical Genetics Unit, Department of Women and Children's Health, CIR-Myo Myology Center, University of Padova, IRP Città della Speranza, Padova, Italy
| | | | - Andriy Shatillo
- Institute of Neurology, Psychiatry and Narcology of NAMS of Ukraine, Kharkiv, Ukraine
| | - F Lucy Raymond
- Cambridge Institute of Medical Research, University of Cambridge, Cambridge, UK
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany
| | - Susana Quijano-Roy
- Neuromuscular Unit, Pediatric Neurology and ICU Department, Raymond Poincaré Hospital (UVSQ), AP-HP Université Paris-Saclay, Garches, France
| | - Johann Böhm
- Département Médecine Translationnelle et Neurogénétique, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Institut National de la Santé et de la Recherche Médicale U1258, Centre National de la Recherche Scientifique UMR7104, Université de Strasbourg, Illkirch, France
| | - Isabelle Nelson
- Sorbonne Université, INSERM, Centre of Research in Myology, UMRS974, Paris, France
| | - Tanya Stojkovic
- APHP, Centre de Référence des Maladies Neuromusculaires Nord/Est/Ile de France, Institut de Myologie, Sorbonne Université, Hôpital Pitié-Salpêtrière, Paris, France
| | - Teresinha Evangelista
- Unité de Morphologie Neuromusculaire, Institut de Myologie, Sorbonne Université, Hôpital Pitié-Salpêtrière, Paris, France
| | - Volker Straub
- John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Norma B Romero
- APHP, Centre de Référence des Maladies Neuromusculaires Nord/Est/Ile de France, Institut de Myologie, Sorbonne Université, Hôpital Pitié-Salpêtrière, Paris, France
- Unité de Morphologie Neuromusculaire, Institut de Myologie, Sorbonne Université, Hôpital Pitié-Salpêtrière, Paris, France
| | - Jocelyn Laporte
- Département Médecine Translationnelle et Neurogénétique, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Institut National de la Santé et de la Recherche Médicale U1258, Centre National de la Recherche Scientifique UMR7104, Université de Strasbourg, Illkirch, France
| | - Francesco Muntoni
- The Dubowitz Neuromuscular Centre, NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, & Great Ormond Street Hospital Trust, London, UK
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), 4-1-1 Ogawahigashi, Kodaira, Tokyo, 187-8502, Japan
- Medical Genome Center, NCNP, Kodaira, Tokyo, Japan
| | - Mark A Tarnopolsky
- Division of Neuromuscular & Neurometabolic Disorders, Department of Pediatrics, McMaster University, Hamilton Health Sciences Centre, Hamilton, ON, Canada
| | - James Shorter
- Department of Biochemistry & Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States
| | - Carsten G Bönnemann
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States.
| | - J Paul Taylor
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, United States.
- Howard Hughes Medical Institute, Chevy Chase, MD, United States.
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Zou J, Yu L, Zhu Y, Yang S, Zhao J, Zhao Y, Jiang M, Xie S, Liu H, Zhao C, Zhou H. Transportin-3 Facilitates Uncoating of Influenza A Virus. Int J Mol Sci 2022; 23:ijms23084128. [PMID: 35456945 PMCID: PMC9027869 DOI: 10.3390/ijms23084128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 03/25/2022] [Accepted: 04/02/2022] [Indexed: 02/01/2023] Open
Abstract
Influenza A viruses (IAVs) are a major global health threat and in the future, may cause the next pandemic. Although studies have partly uncovered the molecular mechanism of IAV–host interaction, it requires further research. In this study, we explored the roles of transportin-3 (TNPO3) in IAV infection. We found that TNPO3-deficient cells inhibited infection with four different IAV strains, whereas restoration of TNPO3 expression in knockout (KO) cells restored IAV infection. TNPO3 overexpression in wild-type (WT) cells promoted IAV infection, suggesting that TNPO3 is involved in the IAV replication. Furthermore, we found that TNPO3 depletion restrained the uncoating in the IAV life cycle, thereby inhibiting the process of viral ribonucleoprotein (vRNP) entry into the nucleus. However, KO of TNPO3 did not affect the virus attachment, endocytosis, or endosomal acidification processes. Subsequently, we found that TNPO3 can colocalize and interact with viral proteins M1 and M2. Taken together, the depletion of TNPO3 inhibits IAV uncoating, thereby inhibiting IAV replication. Our study provides new insights and potential therapeutic targets for unraveling the mechanism of IAV replication and treating influenza disease.
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Affiliation(s)
- Jiahui Zou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Luyao Yu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Yinxing Zhu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Shuaike Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Jiachang Zhao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Yaxin Zhao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Meijun Jiang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Shengsong Xie
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China; (S.X.); (H.L.); (C.Z.)
| | - Hailong Liu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China; (S.X.); (H.L.); (C.Z.)
| | - Changzhi Zhao
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education & Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China; (S.X.); (H.L.); (C.Z.)
| | - Hongbo Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.Z.); (L.Y.); (Y.Z.); (S.Y.); (J.Z.); (Y.Z.); (M.J.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
- Correspondence:
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14
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Lagadec F, Carlon-Andres I, Ragues J, Port S, Wodrich H, Kehlenbach RH. CRM1 Promotes Capsid Disassembly and Nuclear Envelope Translocation of Adenovirus Independently of Its Export Function. J Virol 2022; 96:e0127321. [PMID: 34757845 PMCID: PMC8826800 DOI: 10.1128/jvi.01273-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/01/2021] [Indexed: 11/20/2022] Open
Abstract
After receptor-mediated endocytosis and endosomal escape, adenoviral capsids can travel via microtubule organizing centers to the nuclear envelope. Upon capsid disassembly, viral genome import into nuclei of interphase cells then occurs through nuclear pore complexes, involving the nucleoporins Nup214 and Nup358. Import also requires the activity of the classic nuclear export receptor CRM1, as it is blocked by the selective inhibitor leptomycin B. We have now used artificially enucleated as well as mitotic cells to analyze the role of an intact nucleus in different steps of the viral life cycle. In enucleated U2OS cells, viral capsids traveled to the microtubule organizing center, whereas their removal from this complex was blocked, suggesting that this step required nuclear factors. In mitotic cells, on the other hand, CRM1 promoted capsid disassembly and genome release, suggesting a role of this protein that does not require intact nuclear envelopes or nuclear pore complexes and is distinct from its function as a nuclear export receptor. Similar to enucleation, inhibition of CRM1 by leptomycin B also leads to an arrest of adenoviral capsids at the microtubule organizing center. In a small-scale screen using leptomycin B-resistant versions of CRM1, we identified a mutant, CRM1 W142A P143A, that is compromised with respect to adenoviral capsid disassembly in both interphase and mitotic cells. Strikingly, this mutant is capable of exporting cargo proteins out of the nucleus of living cells or digitonin-permeabilized cells, pointing to a role of the mutated region that is not directly linked to nuclear export. IMPORTANCE A role of nucleoporins and of soluble transport factors in adenoviral genome import into the nucleus of infected cells in interphase has previously been established. The nuclear export receptor CRM1 promotes genome import, but its precise function is not known. Using enucleated and mitotic cells, we showed that CRM1 does not simply function by exporting a crucial factor out of the nucleus that would then trigger capsid disassembly and genome import. Instead, CRM1 has an export-independent role, a notion that is also supported by a mutant, CRM1 W142A P143A, which is export competent but deficient in viral capsid disassembly, in both interphase and mitotic cells.
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Affiliation(s)
- Floriane Lagadec
- Department of Molecular Biology, Faculty of Medicine, Göttingen Center of Biosciences (GZMB), Georg-August-University Göttingen, Göttingen, Germany
- CNRS UMR 5234, Fundamental Microbiology and Pathogenicity, Université de Bordeaux, Bordeaux, France
| | - Irene Carlon-Andres
- CNRS UMR 5234, Fundamental Microbiology and Pathogenicity, Université de Bordeaux, Bordeaux, France
| | - Jessica Ragues
- CNRS UMR 5234, Fundamental Microbiology and Pathogenicity, Université de Bordeaux, Bordeaux, France
| | - Sarah Port
- Department of Molecular Biology, Faculty of Medicine, Göttingen Center of Biosciences (GZMB), Georg-August-University Göttingen, Göttingen, Germany
| | - Harald Wodrich
- CNRS UMR 5234, Fundamental Microbiology and Pathogenicity, Université de Bordeaux, Bordeaux, France
| | - Ralph H. Kehlenbach
- Department of Molecular Biology, Faculty of Medicine, Göttingen Center of Biosciences (GZMB), Georg-August-University Göttingen, Göttingen, Germany
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15
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Kimura M, Imai K, Morinaka Y, Hosono-Sakuma Y, Horton P, Imamoto N. Distinct mutations in importin-β family nucleocytoplasmic transport receptors transportin-SR and importin-13 affect specific cargo binding. Sci Rep 2021; 11:15649. [PMID: 34341383 PMCID: PMC8329185 DOI: 10.1038/s41598-021-94948-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 07/20/2021] [Indexed: 01/25/2023] Open
Abstract
Importin-(Imp)β family nucleocytoplasmic transport receptors (NTRs) are supposed to bind to their cargoes through interaction between a confined interface on an NTR and a nuclear localization or export signal (NLS/NES) on a cargo. Although consensus NLS/NES sequence motifs have been defined for cargoes of some NTRs, many experimentally identified cargoes of those NTRs lack those motifs, and consensus NLSs/NESs have been reported for only a few NTRs. Crystal structures of NTR-cargo complexes have exemplified 3D structure-dependent binding of cargoes lacking a consensus NLS/NES to different sites on an NTR. Since only a limited number of NTR-cargo interactions have been studied, whether most cargoes lacking a consensus NLS/NES bind to the same confined interface or to various sites on an NTR is still unclear. Addressing this issue, we generated four mutants of transportin-(Trn)SR, of which many cargoes lack a consensus NLS, and eight mutants of Imp13, where no consensus NLS has been defined, and we analyzed their binding to as many as 40 cargo candidates that we previously identified by a nuclear import reaction-based method. The cargoes bind differently to the NTR mutants, suggesting that positions on an NTR contribute differently to the binding of respective cargoes.
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Affiliation(s)
- Makoto Kimura
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan.
| | - Kenichiro Imai
- Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan.
- Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan.
| | - Yuriko Morinaka
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan
| | - Yoshiko Hosono-Sakuma
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan
| | - Paul Horton
- Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan City, Taiwan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan.
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16
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Thibault PA, Ganesan A, Kalyaanamoorthy S, Clarke JPWE, Salapa HE, Levin MC. hnRNP A/B Proteins: An Encyclopedic Assessment of Their Roles in Homeostasis and Disease. BIOLOGY 2021; 10:biology10080712. [PMID: 34439945 PMCID: PMC8389229 DOI: 10.3390/biology10080712] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/16/2021] [Accepted: 07/21/2021] [Indexed: 12/13/2022]
Abstract
The hnRNP A/B family of proteins is canonically central to cellular RNA metabolism, but due to their highly conserved nature, the functional differences between hnRNP A1, A2/B1, A0, and A3 are often overlooked. In this review, we explore and identify the shared and disparate homeostatic and disease-related functions of the hnRNP A/B family proteins, highlighting areas where the proteins have not been clearly differentiated. Herein, we provide a comprehensive assembly of the literature on these proteins. We find that there are critical gaps in our grasp of A/B proteins' alternative splice isoforms, structures, regulation, and tissue and cell-type-specific functions, and propose that future mechanistic research integrating multiple A/B proteins will significantly improve our understanding of how this essential protein family contributes to cell homeostasis and disease.
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Affiliation(s)
- Patricia A. Thibault
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
| | - Aravindhan Ganesan
- ArGan’s Lab, School of Pharmacy, Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
| | - Subha Kalyaanamoorthy
- Department of Chemistry, Faculty of Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada;
| | - Joseph-Patrick W. E. Clarke
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Health Sciences, College of Medicine, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Hannah E. Salapa
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
| | - Michael C. Levin
- Office of the Saskatchewan Multiple Sclerosis Clinical Research Chair, University of Saskatchewan, Saskatoon, SK S7K 0M7, Canada; (P.A.T.); (J.-P.W.E.C.); (H.E.S.)
- Department of Medicine, Neurology Division, University of Saskatchewan, Saskatoon, SK S7N 0X8, Canada
- Department of Health Sciences, College of Medicine, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
- Correspondence:
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17
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Han L, Lai H, Yang Y, Hu J, Li Z, Ma B, Xu W, Liu W, Wei W, Li D, Wang Y, Zhai Q, Ji Q, Liao T. A 5'-tRNA halve, tiRNA-Gly promotes cell proliferation and migration via binding to RBM17 and inducing alternative splicing in papillary thyroid cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2021; 40:222. [PMID: 34225773 PMCID: PMC8256553 DOI: 10.1186/s13046-021-02024-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 06/18/2021] [Indexed: 11/10/2022]
Abstract
Background tRNA-derived small noncoding RNAs (sncRNAs) are mainly categorized into tRNA halves (tiRNAs) and fragments (tRFs). Biological functions of tiRNAs in human solid tumor are attracting more and more attention, but researches concerning the mechanisms in tiRNAs-mediated tumorigenesis are rarely. The direct regulatory relationship between tiRNAs and splicing-related proteins remain elusive. Methods Papillary thyroid carcinoma (PTC) associated tRNA fragments were screened by tRNA fragments deep sequencing and validated by qRT-PCR and Northern Blot in PTC tissues. The biological function of tRNA fragments were assessed by cell counting kit, transwells and subcutaneous transplantation tumor of nude mice. For mechanistic study, tRNA fragments pull-down, RNA immunoprecipitation, Western Blot, Immunofluorescence, Immunohistochemical staining were performed. Results Herein, we have identified a 33 nt tiRNA-Gly significantly increases in papillary thyroid cancer (PTC) based on tRFs & tiRNAs sequencing. The ectopic expression of tiRNA-Gly promotes cell proliferation and migration, whereas down-regulation of tiRNA-Gly exhibits reverse effects. Mechanistic investigations reveal tiRNA-Gly directly bind the UHM domain of a splicing-related RNA-binding protein RBM17. The interaction with tiRNA-Gly could translocate RBM17 from cytoplasm into nucleus. In addition, tiRNA-Gly increases RBM17 protein expression via inhibiting its degradation in a ubiquitin/proteasome-dependent way. Moreover, RBM17 level in tiRNA-Gly high-expressing human PTC tissues is upregulated. In vivo mouse model shows that suppression of tiRNA-Gly decreases RBM17 expression. Importantly, tiRNA-Gly can induce exon 16 splicing of MAP4K4 mRNA leading to phosphorylation of downstream signaling pathway, which is RBM17 dependent. Conclusions Our study firstly illustrates tiRNA-Gly can directly bind to RBM17 and display oncogenic effect via RBM17-mediated alternative splicing. This fully novel model broadens our understanding of molecular mechanism in which tRNA fragment in tumor cells directly bind RNA binding protein and play a role in alternative splicing. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-021-02024-3.
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Affiliation(s)
- Litao Han
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Hejing Lai
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.,School of Life Science and Technology, Shanghai Tech University, Shanghai, 200093, China
| | - Yichen Yang
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Jiaqian Hu
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Zhe Li
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.,Fudan University Shanghai Cancer Center, Key Laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Ben Ma
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Weibo Xu
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Wanlin Liu
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Wenjun Wei
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Duanshu Li
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Yu Wang
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China. .,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
| | - Qiwei Zhai
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China. .,School of Life Science and Technology, Shanghai Tech University, Shanghai, 200093, China.
| | - Qinghai Ji
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China. .,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
| | - Tian Liao
- Department of Head and Neck Surgery, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China. .,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
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18
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Ng SC, Güttler T, Görlich D. Recapitulation of selective nuclear import and export with a perfectly repeated 12mer GLFG peptide. Nat Commun 2021; 12:4047. [PMID: 34193851 PMCID: PMC8245513 DOI: 10.1038/s41467-021-24292-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/11/2021] [Indexed: 12/04/2022] Open
Abstract
The permeability barrier of nuclear pore complexes (NPCs) controls nucleocytoplasmic transport. It retains inert macromolecules while allowing facilitated passage of importins and exportins, which in turn shuttle cargo into or out of cell nuclei. The barrier can be described as a condensed phase assembled from cohesive FG repeat domains. NPCs contain several distinct FG domains, each comprising variable repeats. Nevertheless, we now found that sequence heterogeneity is no fundamental requirement for barrier function. Instead, we succeeded in engineering a perfectly repeated 12mer GLFG peptide that self-assembles into a barrier of exquisite transport selectivity and fast transport kinetics. This barrier recapitulates RanGTPase-controlled importin- and exportin-mediated cargo transport and thus represents an ultimately simplified experimental model system. An alternative proline-free sequence forms an amyloid FG phase. Finally, we discovered that FG phases stain bright with ‘DNA-specific’ DAPI/ Hoechst probes, and that such dyes allow for a photo-induced block of nuclear transport. The permeability barrier of nuclear pore complexes blocks passage of inert macromolecules but allows rapid, receptor-mediated, and RanGTPase-driven transport of cargoes up to ribosome size. The authors now show that such a barrier can be faithfully recapitulated by an ultimately simplified FG phase assembled solely from a tandemly repeated 12mer GLFG peptide.
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Affiliation(s)
- Sheung Chun Ng
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Thomas Güttler
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Dirk Görlich
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
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19
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Nucleocytoplasmic Trafficking Perturbation Induced by Picornaviruses. Viruses 2021; 13:v13071210. [PMID: 34201715 PMCID: PMC8310216 DOI: 10.3390/v13071210] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/17/2021] [Accepted: 06/19/2021] [Indexed: 12/15/2022] Open
Abstract
Picornaviruses are positive-stranded RNA viruses. Even though replication and translation of their genome take place in the cytoplasm, these viruses evolved different strategies to disturb nucleocytoplasmic trafficking of host proteins and RNA. The major targets of picornavirus are the phenylalanine-glycine (FG)-nucleoporins, which form a mesh in the central channel of the nuclear pore complex through which protein cargos and karyopherins are actively transported in both directions. Interestingly, while enteroviruses use the proteolytic activity of their 2A protein to degrade FG-nucleoporins, cardioviruses act by triggering phosphorylation of these proteins by cellular kinases. By targeting the nuclear pore complex, picornaviruses recruit nuclear proteins to the cytoplasm, where they increase viral genome translation and replication; they affect nuclear translocation of cytoplasmic proteins such as transcription factors that induce innate immune responses and retain host mRNA in the nucleus thereby preventing cell emergency responses and likely making the ribosomal machinery available for translation of viral RNAs.
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20
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Al-Wassiti HA, Thomas DR, Wagstaff KM, Fabb SA, Jans DA, Johnston AP, Pouton CW. Adenovirus Terminal Protein Contains a Bipartite Nuclear Localisation Signal Essential for Its Import into the Nucleus. Int J Mol Sci 2021; 22:3310. [PMID: 33804953 PMCID: PMC8036708 DOI: 10.3390/ijms22073310] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 01/22/2023] Open
Abstract
Adenoviruses contain dsDNA covalently linked to a terminal protein (TP) at the 5'end. TP plays a pivotal role in replication and long-lasting infectivity. TP has been reported to contain a nuclear localisation signal (NLS) that facilitates its import into the nucleus. We studied the potential NLS motifs within TP using molecular and cellular biology techniques to identify the motifs needed for optimum nuclear import. We used confocal imaging microscopy to monitor the localisation and nuclear association of GFP fusion proteins. We identified two nuclear localisation signals, PV(R)6VP and MRRRR, that are essential for fully efficient TP nuclear entry in transfected cells. To study TP-host interactions further, we expressed TP in Escherichia coli (E. coli). Nuclear uptake of purified protein was determined in digitonin-permeabilised cells. The data confirmed that nuclear uptake of TP requires active transport using energy and shuttling factors. This mechanism of nuclear transport was confirmed when expressed TP was microinjected into living cells. Finally, we uncovered the nature of TP binding to host nuclear shuttling proteins, revealing selective binding to Imp β, and a complex of Imp α/β but not Imp α alone. TP translocation to the nucleus could be inhibited using selective inhibitors of importins. Our results show that the bipartite NLS is required for fully efficient TP entry into the nucleus and suggest that this translocation can be carried out by binding to Imp β or Imp α/β. This work forms the biochemical foundation for future work determining the involvement of TP in nuclear delivery of adenovirus DNA.
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Affiliation(s)
- Hareth A. Al-Wassiti
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne 3800, Australia;
| | - David R. Thomas
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Melbourne 3800, Australia; (D.R.T.); (K.M.W.); (D.A.J.)
| | - Kylie M. Wagstaff
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Melbourne 3800, Australia; (D.R.T.); (K.M.W.); (D.A.J.)
| | - Stewart A. Fabb
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne 3052, Australia;
| | - David A. Jans
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Melbourne 3800, Australia; (D.R.T.); (K.M.W.); (D.A.J.)
| | - Angus P. Johnston
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne 3800, Australia;
| | - Colin W. Pouton
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne 3800, Australia;
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21
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Mboukou A, Rajendra V, Kleinova R, Tisné C, Jantsch MF, Barraud P. Transportin-1: A Nuclear Import Receptor with Moonlighting Functions. Front Mol Biosci 2021; 8:638149. [PMID: 33681296 PMCID: PMC7930572 DOI: 10.3389/fmolb.2021.638149] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 01/13/2021] [Indexed: 12/11/2022] Open
Abstract
Transportin-1 (Trn1), also known as karyopherin-β2 (Kapβ2), is probably the best-characterized nuclear import receptor of the karyopherin-β family after Importin-β, but certain aspects of its functions in cells are still puzzling or are just recently emerging. Since the initial identification of Trn1 as the nuclear import receptor of hnRNP A1 ∼25 years ago, several molecular and structural studies have unveiled and refined our understanding of Trn1-mediated nuclear import. In particular, the understanding at a molecular level of the NLS recognition by Trn1 made a decisive step forward with the identification of a new class of NLSs called PY-NLSs, which constitute the best-characterized substrates of Trn1. Besides PY-NLSs, many Trn1 cargoes harbour NLSs that do not resemble the archetypical PY-NLS, which complicates the global understanding of cargo recognition by Trn1. Although PY-NLS recognition is well established and supported by several structures, the recognition of non-PY-NLSs by Trn1 is far less understood, but recent reports have started to shed light on the recognition of this type of NLSs. Aside from its principal and long-established activity as a nuclear import receptor, Trn1 was shown more recently to moonlight outside nuclear import. Trn1 has for instance been caught in participating in virus uncoating, ciliary transport and in modulating the phase separation properties of aggregation-prone proteins. Here, we focus on the structural and functional aspects of Trn1-mediated nuclear import, as well as on the moonlighting activities of Trn1.
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Affiliation(s)
- Allegra Mboukou
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique (IBPC), UMR 8261, CNRS, Université de Paris, Paris, France
| | - Vinod Rajendra
- Department of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Renata Kleinova
- Department of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Carine Tisné
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique (IBPC), UMR 8261, CNRS, Université de Paris, Paris, France
| | - Michael F. Jantsch
- Department of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Pierre Barraud
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique (IBPC), UMR 8261, CNRS, Université de Paris, Paris, France
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22
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Mehmood R, Jibiki K, Shibazaki N, Yasuhara N. Molecular profiling of nucleocytoplasmic transport factor genes in breast cancer. Heliyon 2021; 7:e06039. [PMID: 33553736 PMCID: PMC7851789 DOI: 10.1016/j.heliyon.2021.e06039] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 12/14/2020] [Accepted: 01/14/2021] [Indexed: 11/24/2022] Open
Abstract
Transport of functional molecules across the nuclear membrane of a eukaryotic cell is regulated by a dedicated set of transporter proteins that carry molecules into the nucleus or out of the nucleus to the cytoplasm for homeostasis of the cell. One of the categories of cargo molecules these transporters carry are the molecules for cell cycle regulation. Therefore, their role is critical in terms of cancer development. Any misregulation of the transport factors would means aberrant abundance of cell cycle regulators and might have consequences in cell cycle progression. While earlier studies have focussed on individual transport related molecules, a collective overview of how these molecules may be dysregulated in breast cancer is lacking. Using genomic and transcriptomic datasets from TCGA (The Cancer Genome Atlas) and microarray platforms, we carried out bioinformatic analysis and provide a genetic and molecular profile of all the molecules directly related to nucleocytoplasmic shuttling of proteins and RNAs. Interestingly, we identified that many of these molecules are either mutated or have dysregulated expression in breast cancer. Strikingly, some of the molecules, namely, KPNA2, KPNA3, KPNA5, IPO8, TNPO1, XPOT, XPO7 and CSE1L were correlated with poor patient survival. This study provides a comprehensive genetic and molecular landscape of nucleocytoplasmic factors in breast cancer and points to the important roles of various nucleocytoplasmic factors in cancer progression. This data might have implications in prognosis and therapeutic targeting in breast cancer.
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Affiliation(s)
- Rashid Mehmood
- Department of Life Sciences, College of Science and General Studies, Alfaisal University, Riyadh, Kingdom of Saudi Arabia
| | - Kazuya Jibiki
- Graduate School of Integrated Basic Sciences, Nihon University, Setagaya-ku, Tokyo, Japan
| | - Noriko Shibazaki
- Graduate School of Integrated Basic Sciences, Nihon University, Setagaya-ku, Tokyo, Japan
| | - Noriko Yasuhara
- Graduate School of Integrated Basic Sciences, Nihon University, Setagaya-ku, Tokyo, Japan
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23
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Levengood JD, Peterson J, Tolbert BS, Roche J. Thermodynamic stability of hnRNP A1 low complexity domain revealed by high-pressure NMR. Proteins 2021; 89:781-791. [PMID: 33550645 DOI: 10.1002/prot.26058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 12/21/2020] [Accepted: 01/31/2021] [Indexed: 11/09/2022]
Abstract
We have investigated the pressure- and temperature-induced conformational changes associated with the low complexity domain of hnRNP A1, an RNA-binding protein able to phase separate in response to cellular stress. Solution NMR spectra of the hnRNP A1 low-complexity domain fused with protein-G B1 domain were collected from 1 to 2500 bar and from 268 to 290 K. While the GB1 domain shows the typical pressure-induced and cold temperature-induced unfolding expected for small globular domains, the low-complexity domain of hnRNP A1 exhibits unusual pressure and temperature dependences. We observed that the low-complexity domain is pressure sensitive, undergoing a major conformational transition within the prescribed pressure range. Remarkably, this transition has the inverse temperature dependence of a typical folding-unfolding transition. Our results suggest the presence of a low-lying extended and fully solvated state(s) of the low-complexity domain that may play a role in phase separation. This study highlights the exquisite sensitivity of solution NMR spectroscopy to observe subtle conformational changes and illustrates how pressure perturbation can be used to determine the properties of metastable conformational ensembles.
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Affiliation(s)
- Jeffrey D Levengood
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, USA
| | - Jake Peterson
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, USA
| | - Blanton S Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, USA
| | - Julien Roche
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, USA
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24
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Paci G, Caria J, Lemke EA. Cargo transport through the nuclear pore complex at a glance. J Cell Sci 2021; 134:237315. [PMID: 33495357 DOI: 10.1242/jcs.247874] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Bidirectional transport of macromolecules across the nuclear envelope is a hallmark of eukaryotic cells, in which the genetic material is compartmentalized inside the nucleus. The nuclear pore complex (NPC) is the major gateway to the nucleus and it regulates nucleocytoplasmic transport, which is key to processes including transcriptional regulation and cell cycle control. Accordingly, components of the nuclear transport machinery are often found to be dysregulated or hijacked in diseases. In this Cell Science at a Glance article and accompanying poster, we provide an overview of our current understanding of cargo transport through the NPC, from the basic transport signals and machinery to more emerging aspects, all from a 'cargo perspective'. Among these, we discuss the transport of large cargoes (>15 nm), as well as the roles of different cargo properties to nuclear transport, from size and number of bound nuclear transport receptors (NTRs), to surface and mechanical properties.
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Affiliation(s)
- Giulia Paci
- Biocentre, Johannes Gutenberg-University Mainz, Hans-Dieter-Hüsch-Weg 15, 555128 Mainz, Germany.,Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany.,European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Joana Caria
- Biocentre, Johannes Gutenberg-University Mainz, Hans-Dieter-Hüsch-Weg 15, 555128 Mainz, Germany.,Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany.,European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Edward A Lemke
- Biocentre, Johannes Gutenberg-University Mainz, Hans-Dieter-Hüsch-Weg 15, 555128 Mainz, Germany .,Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany.,European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
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25
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Sun G, Zhou H, Chen K, Zeng J, Zhang Y, Yan L, Yao W, Hu J, Wang T, Xing J, Xiao K, Wu L, Ye Z, Xu H. HnRNP A1 - mediated alternative splicing of CCDC50 contributes to cancer progression of clear cell renal cell carcinoma via ZNF395. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2020; 39:116. [PMID: 32560659 PMCID: PMC7304168 DOI: 10.1186/s13046-020-01606-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/28/2020] [Indexed: 01/26/2023]
Abstract
BACKGROUND Aberrant alternative splicing events play critical roles in carcinogenesis and progression of many cancers, while sparse studies regarding to alternative splicing are available for clear cell renal cell carcinoma (ccRCC). We identified that alternative splicing of coiled-coil domain containing 50 (CCDC50) was dysregulated in ccRCC, whereas the clinical significance of this splicing event and its splicing regulation mechanisms were still elusive. METHODS Bioinformatic algorithm was utilized to identify significant exon skipping events in ccRCC via exon sequencing data from The Cancer Genome Atlas. Semi-quantitative real-time polymerase chain reaction and western blot were used to validate the aberrant expression of different transcripts in renal cancer tissues, cell lines and corresponding noncancerous controls. Short hairpin RNA targeting CCDC50 and overexpressing plasmids for each transcript were introduced into ccRCC cell lines, followed by a series of in vitro and in vivo functional experiments. Moreover, a panel of splicing factors were identified and their roles on splicing regulation of CCDC50 precursor mRNA (pre-mRNA) were studied. Furthermore, RNAseq data were analyzed to elucidate downstream molecules of CCDC50. Two-way analysis of variance and unpaired Student t test were used in statistical analysis. RESULTS Pre-mRNA of CCDC50 generated two transcripts, full-length transcript (CCDC50-FL) and truncated transcript (CCDC50-S) with exon 6 skipped. CCDC50-S was overexpressed in ccRCC tissues and cell lines compared to noncancerous counterparts, but CCDC50-FL was only detected in noncancerous tissues and normal renal epithelial cells. Higher percent spliced-in index was associated with better survival in ccRCC patients. In vitro and in vivo functional experiments indicated that CCDC50-S transcript promoted the proliferation, migration, invasion and tumorigenesis of ccRCC, while CCDC50-FL exerted opposite tumor suppressive functions. Besides, we identified that heterogeneous nuclear ribonucleoprotein A1 (HnRNP A1) could promote the skipping of exon 6, which resulted in higher portion of CCDC50-S and oncogenic transformation. Moreover, zinc finger protein 395 (ZNF395) was identified as a downstream protein of CCDC50-S, and the interaction initiated oncogenic pathways which were involved in ccRCC progression. CONCLUSIONS Aberrant alternative splicing of CCDC50 is regulated by HnRNP A1 in ccRCC. This splicing event contributes to cancer progression through the downstream pathway involving ZNF395.
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Affiliation(s)
- Guoliang Sun
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Hui Zhou
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Ke Chen
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Jin Zeng
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Yangjun Zhang
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Libin Yan
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Weimin Yao
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Junhui Hu
- Hubei Institute of Urology, Wuhan, 430030 P.R. China ,grid.19006.3e0000 0000 9632 6718Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 USA
| | - Tao Wang
- grid.412625.6Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, 361000 P.R. China
| | - Jinchun Xing
- grid.412625.6Department of Urology, The First Affiliated Hospital of Xiamen University, Xiamen, 361000 P.R. China
| | - Kefeng Xiao
- Department of Urology, The People’s Hospital of Shenzhen City, Shenzhen, 518000 P.R. China
| | - Lily Wu
- grid.19006.3e0000 0000 9632 6718Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095 USA
| | - Zhangqun Ye
- grid.33199.310000 0004 0368 7223Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China ,Hubei Institute of Urology, Wuhan, 430030 P.R. China
| | - Hua Xu
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, P.R. China. .,Hubei Institute of Urology, Wuhan, 430030, P.R. China.
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26
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Springhower CE, Rosen MK, Chook YM. Karyopherins and condensates. Curr Opin Cell Biol 2020; 64:112-123. [PMID: 32474299 DOI: 10.1016/j.ceb.2020.04.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/26/2020] [Accepted: 04/04/2020] [Indexed: 01/25/2023]
Abstract
Several aggregation-prone RNA-binding proteins, including FUS, EWS, TAF15, hnRNP A1, hnRNP A2, and TDP-43, are mutated in neurodegenerative diseases. The nuclear-cytoplasmic distribution of these proteins is controlled by proteins in the karyopherin family of nuclear transport factors (Kaps). Recent studies have shown that Kaps not only transport these proteins but also inhibit their self-association/aggregation, acting as molecular chaperones. This chaperone activity is impaired for disease-causing mutants of the RNA-binding proteins. Here, we review physical data on the mechanisms of self-association of several disease-associated RNA-binding proteins, through liquid-liquid phase separation and amyloid fiber formation. In each case, we relate these data to biophysical, biochemical, and cell biological data on the inhibition of self-association by Kaps. Our analyses suggest that Kaps may be effective chaperones because they contain large surfaces with diverse physical properties that enable them to engage multiple different regions of their cargo proteins, blocking self-association.
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Affiliation(s)
- Charis E Springhower
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Michael K Rosen
- Department of Biophysics and Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Yuh Min Chook
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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27
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Moore S, Rabichow BE, Sattler R. The Hitchhiker's Guide to Nucleocytoplasmic Trafficking in Neurodegeneration. Neurochem Res 2020; 45:1306-1327. [PMID: 32086712 DOI: 10.1007/s11064-020-02989-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 02/12/2020] [Accepted: 02/14/2020] [Indexed: 12/12/2022]
Abstract
The widespread nature of nucleocytoplasmic trafficking defects and protein accumulation suggests distinct yet overlapping mechanisms in a variety of neurodegenerative diseases. Detailed understanding of the cellular pathways involved in nucleocytoplasmic transport and its dysregulation are essential for elucidating neurodegenerative pathogenesis and pinpointing potential areas for therapeutic intervention. The transport of cargos from the nucleus to the cytoplasm is generally regulated by the structure and function of the nuclear pore as well as the karyopherin α/β, importin, exportin, and mRNA export mechanisms. The disruption of these crucial transport mechanisms has been extensively described in the context of neurodegenerative diseases. One common theme in neurodegeneration is the cytoplasmic aggregation of proteins, including nuclear RNA binding proteins, repeat expansion associated gene products, and tau. These cytoplasmic aggregations are partly a consequence of failed nucleocytoplasmic transport machinery, but can also further disrupt transport, creating cyclical feed-forward mechanisms that exacerbate neurodegeneration. Here we describe the canonical mechanisms that regulate nucleocytoplasmic trafficking as well as how these mechanisms falter in neurodegenerative diseases.
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Affiliation(s)
- Stephen Moore
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA.,School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Benjamin E Rabichow
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA
| | - Rita Sattler
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA.
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28
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Abstract
Influenza A virus (IAV) is an enveloped virus of the Orthomyxoviridae with a negative-sense single-stranded RNA genome. During virus cell entry, viral and cellular cues are delivered in a stepwise manner within two distinct cellular compartments-the endosomes and the cytosol. Endosome maturation primes the viral core for uncoating by cytosolic host proteins and host-mediated virus disaggregation is essential for genome import and replication in the nucleus. Recent evidence shows that two well-known cellular proteins-histone deacetylase 6 (HDAC6) and karyopherin-β2 (kapβ2)-uncoat influenza virus. HDAC6 is 1 of 11 HDACs and an X-linked, cytosolic lysine deacetylase. Under normal cellular conditions HDAC6 is the tubulin deacetylase. Under proteasomal stress HDAC6 binds unanchored ubiquitin, dynein and myosin II to sequester misfolded protein aggregates for autophagy. Kapβ2 is a member of the importin β family that transports RNA-binding proteins into the nucleus by binding to disordered nuclear localization signals (NLSs) known as PY-NLS. Kapβ2 is emerging as a universal uncoating factor for IAV and human immunodeficiency virus type 1 (HIV-1). Kapβ2 can also reverse liquid-liquid phase separation (LLPS) of RNA-binding proteins by promoting their disaggregation. Thus, it is becoming evident that key players in the management of cellular condensates and membraneless organelles are potent virus uncoating factors. This emerging concept reveals implications in viral pathogenesis, as well as, the promise for cell-targeted therapeutic strategies to block universal virus uncoating pathways hijacked by enveloped RNA viruses.
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Affiliation(s)
- Yohei Yamauchi
- School of Cellular & Molecular Medicine, University of Bristol, Bristol, United Kingdom.
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29
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Kaur R, Lal SK. The multifarious roles of heterogeneous ribonucleoprotein A1 in viral infections. Rev Med Virol 2020; 30:e2097. [PMID: 31989716 PMCID: PMC7169068 DOI: 10.1002/rmv.2097] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 12/19/2019] [Accepted: 12/30/2019] [Indexed: 12/13/2022]
Abstract
Viruses are obligate parasites known to interact with a wide variety of host proteins at different stages of infection. Current antiviral treatments target viral proteins and may be compromised due to the emergence of drug resistant viral strains. Targeting viral-host interactions is now gaining recognition as an alternative approach against viral infections. Recent research has revealed that heterogeneous ribonucleoprotein A1, an RNA-binding protein, plays an essential functional and regulatory role in the life cycle of many viruses. In this review, we summarize the interactions between heterogeneous ribonucleoprotein A1 (hnRNPA1) and multiple viral proteins during the life cycle of RNA and DNA viruses. hnRNPA1 protein levels are modulated differently, in different viruses, which further dictates its stability, function, and intracellular localization. Multiple reports have emphasized that in Sindbis virus, enteroviruses, porcine endemic diarrhea virus, and rhinovirus infection, hnRNPA1 enhances viral replication and survival. However, in others like hepatitis C virus and human T-cell lymphotropic virus, it exerts a protective response. The involvement of hnRNPA1 in viral infections highlights its importance as a central regulator of host and viral gene expression. Understanding the nature of these interactions will increase our understanding of specific viral infections and pathogenesis and eventually aid in the development of novel and robust antiviral intervention strategies.
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Affiliation(s)
- Ramandeep Kaur
- Tropical Medicine and Biology Platform & School of Science, Monash University, 47500 Bandar Sunway, Selangor DE, Malaysia
| | - Sunil K Lal
- Tropical Medicine and Biology Platform & School of Science, Monash University, 47500 Bandar Sunway, Selangor DE, Malaysia
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30
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Ribeiro-Oliveira R, Vojtek M, Gonçalves-Monteiro S, Vieira-Rocha MS, Sousa JB, Gonçalves J, Diniz C. Nuclear G-protein-coupled receptors as putative novel pharmacological targets. Drug Discov Today 2019; 24:2192-2201. [DOI: 10.1016/j.drudis.2019.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/15/2019] [Accepted: 09/05/2019] [Indexed: 12/14/2022]
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Ferreira PA. The coming-of-age of nucleocytoplasmic transport in motor neuron disease and neurodegeneration. Cell Mol Life Sci 2019; 76:2247-2273. [PMID: 30742233 PMCID: PMC6531325 DOI: 10.1007/s00018-019-03029-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 01/28/2019] [Indexed: 12/11/2022]
Abstract
The nuclear pore is the gatekeeper of nucleocytoplasmic transport and signaling through which a vast flux of information is continuously exchanged between the nuclear and cytoplasmic compartments to maintain cellular homeostasis. A unifying and organizing principle has recently emerged that cements the notion that several forms of amyotrophic lateral sclerosis (ALS), and growing number of other neurodegenerative diseases, co-opt the dysregulation of nucleocytoplasmic transport and that this impairment is a pathogenic driver of neurodegeneration. The understanding of shared pathomechanisms that underpin neurodegenerative diseases with impairments in nucleocytoplasmic transport and how these interface with current concepts of nucleocytoplasmic transport is bound to illuminate this fundamental biological process in a yet more physiological context. Here, I summarize unresolved questions and evidence and extend basic and critical concepts and challenges of nucleocytoplasmic transport and its role in the pathogenesis of neurodegenerative diseases, such as ALS. These principles will help to appreciate the roles of nucleocytoplasmic transport in the pathogenesis of ALS and other neurodegenerative diseases, and generate a framework for new ideas of the susceptibility of motoneurons, and possibly other neurons, to degeneration by dysregulation of nucleocytoplasmic transport.
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Affiliation(s)
- Paulo A Ferreira
- Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA.
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32
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Fung L, Guzman H, Sevrioukov E, Idica A, Park E, Bochnakian A, Daugaard I, Jury D, Mortazavi A, Zisoulis DG, Pedersen IM. miR-128 Restriction of LINE-1 (L1) Retrotransposition Is Dependent on Targeting hnRNPA1 mRNA. Int J Mol Sci 2019; 20:E1955. [PMID: 31010097 PMCID: PMC6515209 DOI: 10.3390/ijms20081955] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/15/2019] [Accepted: 04/19/2019] [Indexed: 12/25/2022] Open
Abstract
The majority of the human genome is made of transposable elements, giving rise to interspaced repeats, including Long INterspersed Element-1s (LINE-1s or L1s). L1s are active human transposable elements involved in genomic diversity and evolution; however, they can also contribute to genomic instability and diseases. L1s require host factors to complete their life cycles, whereas the host has evolved numerous mechanisms to restrict L1-induced mutagenesis. Restriction mechanisms in somatic cells include methylation of the L1 promoter, anti-viral factors and RNA-mediated processes such as small RNAs. microRNAs (miRNAs or miRs) are small non-coding RNAs that post-transcriptionally repress multiple target genes often found in the same cellular pathways. We have recently established that miR-128 functions as a novel restriction factor inhibiting L1 mobilization in somatic cells. We have further demonstrated that miR-128 functions through a dual mechanism; by directly targeting L1 RNA for degradation and indirectly by inhibiting a cellular co-factor which L1 is dependent on to transpose to new genomic locations (TNPO1). Here, we add another piece to the puzzle of the enigmatic L1 lifecycle. We show that miR-128 also inhibits another key cellular factor, hnRNPA1 (heterogeneous nuclear ribonucleoprotein A1), by significantly reducing mRNA and protein levels through direct interaction with the coding sequence (CDS) of hnRNPA1 mRNA. In addition, we demonstrate that repression of hnRNPA1 using hnRNPA1-shRNA significantly decreases de novo L1 retro-transposition and that induced hnRNPA1 expression enhances L1 mobilization. Furthermore, we establish that hnRNPA1 is a functional target of miR-128. Finally, we determine that induced hnRNPA1 expression in miR-128-overexpressing cells can partly rescue the miR-128-induced repression of L1's ability to transpose to different genomic locations. Thus, we have identified an additional mechanism by which miR-128 represses L1 retro-transposition and mediates genomic stability.
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Affiliation(s)
- Lianna Fung
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Herlinda Guzman
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Evgueni Sevrioukov
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Adam Idica
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Eddie Park
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, USA.
| | - Aurore Bochnakian
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Iben Daugaard
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Douglas Jury
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, USA.
| | - Dimitrios G Zisoulis
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
| | - Irene M Pedersen
- Department of Molecular Biology and Biochemistry, Francisco J. AyalaSchool of Biological Sciences, University of California, Irvine, CA 92697, USA.
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Gittings LM, Foti SC, Benson BC, Gami-Patel P, Isaacs AM, Lashley T. Heterogeneous nuclear ribonucleoproteins R and Q accumulate in pathological inclusions in FTLD-FUS. Acta Neuropathol Commun 2019; 7:18. [PMID: 30755280 PMCID: PMC6371513 DOI: 10.1186/s40478-019-0673-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 02/03/2019] [Indexed: 12/14/2022] Open
Abstract
Frontotemporal lobar degeneration (FTLD) is pathologically subdivided based on the presence of particular pathological proteins that are identified in inclusion bodies observed post-mortem. The FTLD-FUS subgroup is defined by the presence of the fused in sarcoma protein (FUS) in pathological inclusions. FUS is a heterogeneous nuclear ribonucleoprotein (hnRNP) protein and a member of the FET (FUS, EWS, TAF15) protein family. It shuttles between the nucleus and cytoplasm, and has been implicated in many cellular functions including translation, splicing, and RNA transport. EWS, TAF15 and the nuclear import receptor transportin have been shown to co-accumulate with FUS in neuronal inclusions specifically in FTLD-FUS, with transportin-positive inclusions most frequently observed. Here, we report the identification of hnRNP R and hnRNP Q in neuronal cytoplasmic and intranuclear inclusions in the frontal cortex and hippocampus of FTLD-FUS patients, as frequently as transportin. hnRNP R and hnRNP Q were not found in the characteristic pathological inclusions observed in FTLD-TDP (subtypes A-C). Additionally, we studied the expression of hnRNP R in the frontal and temporal cortices from patients with FTLD and found significantly increased expression of the heterogeneous nuclear ribonucleoprotein R in several FTLD disease groups. Our identification of the frequent presence of hnRNP R and hnRNP Q in FTLD-FUS inclusions suggests a potential role for these hnRNPs in FTLD-FUS pathogenesis and supports the role of dysfunctional RNA metabolism in FTLD.
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34
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Levengood JD, Tolbert BS. Idiosyncrasies of hnRNP A1-RNA recognition: Can binding mode influence function. Semin Cell Dev Biol 2019; 86:150-161. [PMID: 29625167 PMCID: PMC6177329 DOI: 10.1016/j.semcdb.2018.04.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/27/2018] [Accepted: 04/03/2018] [Indexed: 12/21/2022]
Abstract
The heterogeneous nuclear ribonucleoproteins (hnRNPs) are a diverse family of RNA binding proteins that function in most stages of RNA metabolism. The prototypical member, hnRNP A1, is composed of three major domains; tandem N-terminal RNA Recognition Motifs (RRMs) and a C-terminal mostly intrinsically disordered region. HnRNP A1 is broadly implicated in basic cellular RNA processing events such as splicing, stability, nuclear export and translation. Due to its ubiquity and abundance, hnRNP A1 is also frequently usurped to control viral gene expression. Deregulation of the RNA metabolism functions of hnRNP A1 in neuronal cells contributes to several neurodegenerative disorders. Because of these roles in human pathologies, the study of hnRNP A1 provides opportunities for the development of novel therapeutics, with disruption of its RNA binding capabilities being the most promising target. The functional diversity of hnRNP A1 is reflected in the complex nature by which it interacts with various RNA targets. Indeed, hnRNP A1 binds both structured and unstructured RNAs with binding affinities that span several magnitudes. Available structures of hnRNP A1-RNA complexes also suggest a degree of plasticity in molecular recognition. Given the reinvigoration in hnRNP A1, the goal of this review is to use the available structural biochemical developments as a framework to interpret its wide-range of RNA functions.
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Affiliation(s)
- Jeffrey D Levengood
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, United States
| | - Blanton S Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, United States.
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35
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36
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Influenza virus uses transportin 1 for vRNP debundling during cell entry. Nat Microbiol 2019; 4:578-586. [PMID: 30692667 DOI: 10.1038/s41564-018-0332-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 11/28/2018] [Indexed: 12/15/2022]
Abstract
Influenza A virus is a pathogen of great medical impact. To develop novel antiviral strategies, it is essential to understand the molecular aspects of virus-host cell interactions in detail. During entry, the viral ribonucleoproteins (vRNPs) that carry the RNA genome must be released from the incoming particle before they can enter the nucleus for replication. The uncoating process is facilitated by histone deacetylase 6 (ref.1). However, the precise mechanism of shell opening and vRNP debundling is unknown. Here, we show that transportin 1, a member of the importin-β family proteins, binds to a PY-NLS2 sequence motif close to the amino terminus of matrix protein (M1) exposed during acid priming of the viral core. It promotes the removal of M1 and induces disassembly of vRNP bundles. Next, the vRNPs interact with importin-α/β and enter the nucleus. Thus, influenza A virus uses dual importin-βs for distinct steps in host cell entry.
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Targeting of LRRC59 to the Endoplasmic Reticulum and the Inner Nuclear Membrane. Int J Mol Sci 2019; 20:ijms20020334. [PMID: 30650545 PMCID: PMC6359192 DOI: 10.3390/ijms20020334] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/08/2019] [Accepted: 01/10/2019] [Indexed: 01/12/2023] Open
Abstract
LRRC59 (leucine-rich repeat-containing protein 59) is a tail-anchored protein with a single transmembrane domain close to its C-terminal end that localizes to the endoplasmic reticulum (ER) and the nuclear envelope. Here, we investigate the mechanisms of membrane integration of LRRC59 and its targeting to the inner nuclear membrane (INM). Using purified microsomes, we show that LRRC59 can be post-translationally inserted into ER-derived membranes. The TRC-pathway, a major route for post-translational membrane insertion, is not required for LRRC59. Like emerin, another tail-anchored protein, LRRC59 reaches the INM, as demonstrated by rapamycin-dependent dimerization assays. Using different approaches to inhibit importin α/β-dependent nuclear import of soluble proteins, we show that the classic nuclear transport machinery does not play a major role in INM-targeting of LRRC59. Instead, the size of the cytoplasmic domain of LRRC59 is an important feature, suggesting that targeting is governed by passive diffusion.
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Tavolieri MV, Droppelmann CA, Campos-Melo D, Volkening K, Strong MJ. A novel overlapping NLS/NES region within the PH domain of Rho Guanine Nucleotide Exchange Factor (RGNEF) regulates its nuclear-cytoplasmic localization. Eur J Cell Biol 2019; 98:27-35. [PMID: 30482479 DOI: 10.1016/j.ejcb.2018.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/08/2018] [Accepted: 11/13/2018] [Indexed: 10/27/2022] Open
Abstract
Rho Guanine Nucleotide Exchange Factor (RGNEF) is a 190 kDa protein implicated in both amyotrophic lateral sclerosis (ALS) and cancer. Under normal physiological conditions, RGNEF is predominantly cytoplasmic with moderate levels of nuclear localization. We have identified a 23-amino acid region containing a bipartite nuclear localization signal (NLS) within the Pleckstrin Homology (PH) domain of RGNEF, which when deleted or mutated abolishes the nuclear localization of this protein. Fusion proteins containing only the PH domain demonstrated that this region by itself is able to translocate a 160 kDa protein to the nucleus. Interestingly, we also detected a nuclear export signal (NES) within the linker region of this bipartite NLS which is able to export from the nucleus a fusion protein containing two NLSs. Experiments using Leptomycin-B -an inhibitor of nuclear export- confirmed that this region promotes nuclear export in an exportin-1 dependent manner. This study is the first report demonstrating either of these signals embedded within a PH domain. Notably, this is also the first description of a functional overlapped NLS/NES signal.
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Affiliation(s)
- Michael V Tavolieri
- Department of Clinical Neurological Sciences, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada.
| | - Cristian A Droppelmann
- Molecular Medicine Group, Robarts Research Institute, Western University, London, Ontario, Canada.
| | - Danae Campos-Melo
- Molecular Medicine Group, Robarts Research Institute, Western University, London, Ontario, Canada.
| | - Kathryn Volkening
- Department of Clinical Neurological Sciences, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada; Molecular Medicine Group, Robarts Research Institute, Western University, London, Ontario, Canada.
| | - Michael J Strong
- Department of Clinical Neurological Sciences, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada; Molecular Medicine Group, Robarts Research Institute, Western University, London, Ontario, Canada.
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Zhao M, Kim JR, van Bruggen R, Park J. RNA-Binding Proteins in Amyotrophic Lateral Sclerosis. Mol Cells 2018; 41:818-829. [PMID: 30157547 PMCID: PMC6182225 DOI: 10.14348/molcells.2018.0243] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 07/23/2018] [Accepted: 08/10/2018] [Indexed: 12/11/2022] Open
Abstract
Significant research efforts are ongoing to elucidate the complex molecular mechanisms underlying amyotrophic lateral sclerosis (ALS), which may in turn pinpoint potential therapeutic targets for treatment. The ALS research field has evolved with recent discoveries of numerous genetic mutations in ALS patients, many of which are in genes encoding RNA binding proteins (RBPs), including TDP-43, FUS, ATXN2, TAF15, EWSR1, hnRNPA1, hnRNPA2/B1, MATR3 and TIA1. Accumulating evidence from studies on these ALS-linked RBPs suggests that dysregulation of RNA metabolism, cytoplasmic mislocalization of RBPs, dysfunction in stress granule dynamics of RBPs and increased propensity of mutant RBPs to aggregate may lead to ALS pathogenesis. Here, we review current knowledge of the biological function of these RBPs and the contributions of ALS-linked mutations to disease pathogenesis.
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Affiliation(s)
- Melody Zhao
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
- Department of Molecular Genetics, University of Toronto, Toronto,
Canada
| | - Jihye Rachel Kim
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
- Department of Molecular Genetics, University of Toronto, Toronto,
Canada
| | - Rebekah van Bruggen
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
| | - Jeehye Park
- Genetics and Genome Biology Program, The Hospital for Sick Children, Toronto,
Canada
- Department of Molecular Genetics, University of Toronto, Toronto,
Canada
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40
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Tanaka T, Kasai M, Kobayashi S. Mechanism responsible for inhibitory effect of indirubin 3′-oxime on anticancer agent-induced YB-1 nuclear translocation in HepG2 human hepatocellular carcinoma cells. Exp Cell Res 2018; 370:454-460. [DOI: 10.1016/j.yexcr.2018.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 07/03/2018] [Indexed: 12/23/2022]
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41
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Rodriguez-Bravo V, Pippa R, Song WM, Carceles-Cordon M, Dominguez-Andres A, Fujiwara N, Woo J, Koh AP, Ertel A, Lokareddy RK, Cuesta-Dominguez A, Kim RS, Rodriguez-Fernandez I, Li P, Gordon R, Hirschfield H, Prats JM, Reddy EP, Fatatis A, Petrylak DP, Gomella L, Kelly WK, Lowe SW, Knudsen KE, Galsky MD, Cingolani G, Lujambio A, Hoshida Y, Domingo-Domenech J. Nuclear Pores Promote Lethal Prostate Cancer by Increasing POM121-Driven E2F1, MYC, and AR Nuclear Import. Cell 2018; 174:1200-1215.e20. [PMID: 30100187 DOI: 10.1016/j.cell.2018.07.015] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 04/16/2018] [Accepted: 07/10/2018] [Indexed: 12/19/2022]
Abstract
Nuclear pore complexes (NPCs) regulate nuclear-cytoplasmic transport, transcription, and genome integrity in eukaryotic cells. However, their functional roles in cancer remain poorly understood. We interrogated the evolutionary transcriptomic landscape of NPC components, nucleoporins (Nups), from primary to advanced metastatic human prostate cancer (PC). Focused loss-of-function genetic screen of top-upregulated Nups in aggressive PC models identified POM121 as a key contributor to PC aggressiveness. Mechanistically, POM121 promoted PC progression by enhancing importin-dependent nuclear transport of key oncogenic (E2F1, MYC) and PC-specific (AR-GATA2) transcription factors, uncovering a pharmacologically targetable axis that, when inhibited, decreased tumor growth, restored standard therapy efficacy, and improved survival in patient-derived pre-clinical models. Our studies molecularly establish a role of NPCs in PC progression and give a rationale for NPC-regulated nuclear import targeting as a therapeutic strategy for lethal PC. These findings may have implications for understanding how NPC deregulation contributes to the pathogenesis of other tumor types.
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Affiliation(s)
- Veronica Rodriguez-Bravo
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Pathology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Raffaella Pippa
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Pathology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Won-Min Song
- Genetic and Genomic Sciences Department. Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Marc Carceles-Cordon
- Pathology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ana Dominguez-Andres
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Pathology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Naoto Fujiwara
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jungreem Woo
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Pathology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Anna P Koh
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Adam Ertel
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Ravi K Lokareddy
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Alvaro Cuesta-Dominguez
- Oncological Sciences Department. Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Division of Liver Diseases, Medicine Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Rosa S Kim
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | | | - Peiyao Li
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Ronald Gordon
- Pathology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Hadassa Hirschfield
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Josep M Prats
- Urology Department, Hospital de Calella, Barcelona 08370, Spain
| | - E Premkumar Reddy
- Oncological Sciences Department. Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Alessandro Fatatis
- Pharmacology and Physiology Department, Drexler University, Philadelphia, PA 19104, USA
| | - Daniel P Petrylak
- Medical Oncology Department, Yale Comprehensive Cancer Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Leonard Gomella
- Urology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - W Kevin Kelly
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Urology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Scott W Lowe
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Karen E Knudsen
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Urology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Matthew D Galsky
- Medical Oncology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Gino Cingolani
- Department of Biochemistry and Molecular Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Amaia Lujambio
- Oncological Sciences Department. Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Division of Liver Diseases, Medicine Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yujin Hoshida
- Liver Tumor Translational Research Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Josep Domingo-Domenech
- Cancer Biology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Medical Oncology Department, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA; Pathology Department, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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Larrieu D, Viré E, Robson S, Breusegem SY, Kouzarides T, Jackson SP. Inhibition of the acetyltransferase NAT10 normalizes progeric and aging cells by rebalancing the Transportin-1 nuclear import pathway. Sci Signal 2018; 11:eaar5401. [PMID: 29970603 PMCID: PMC6331045 DOI: 10.1126/scisignal.aar5401] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Hutchinson-Gilford progeria syndrome (HGPS) is an incurable premature aging disease. Identifying deregulated biological processes in HGPS might thus help define novel therapeutic strategies. Fibroblasts from HGPS patients display defects in nucleocytoplasmic shuttling of the GTP-bound form of the small GTPase Ran (RanGTP), which leads to abnormal transport of proteins into the nucleus. We report that microtubule stabilization in HGPS cells sequestered the nonclassical nuclear import protein Transportin-1 (TNPO1) in the cytoplasm, thus affecting the nuclear localization of its cargo, including the nuclear pore protein NUP153. Consequently, nuclear Ran, nuclear anchorage of the nucleoporin TPR, and chromatin organization were disrupted, deregulating gene expression and inducing senescence. Inhibiting N-acetyltransferase 10 (NAT10) ameliorated HGPS phenotypes by rebalancing the nuclear to cytoplasmic ratio of TNPO1. This restored nuclear pore complex integrity and nuclear Ran localization, thereby correcting HGPS cellular phenotypes. We observed a similar mechanism in cells from healthy aged individuals. This study identifies a nuclear import pathway affected in aging and underscores the potential for NAT10 inhibition as a possible therapeutic strategy for HGPS and perhaps also for pathologies associated with normal aging.
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Affiliation(s)
- Delphine Larrieu
- The Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, CB2 1QN, UK.
| | - Emmanuelle Viré
- The Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, CB2 1QN, UK
| | - Samuel Robson
- The Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, CB2 1QN, UK
| | - Sophia Y Breusegem
- The Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, CB2 1QN, UK
| | - Tony Kouzarides
- The Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, CB2 1QN, UK
| | - Stephen P Jackson
- The Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, CB2 1QN, UK.
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43
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Lång A, Øye A, Eriksson J, Rowe AD, Lång E, Bøe SO. Influence of acute promyelocytic leukemia therapeutic drugs on nuclear pore complex density and integrity. Biochem Biophys Res Commun 2018; 499:570-576. [PMID: 29596829 DOI: 10.1016/j.bbrc.2018.03.191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 03/25/2018] [Indexed: 11/16/2022]
Abstract
During cell division, a large number of nuclear proteins are released into the cytoplasm due to nuclear envelope breakdown. Timely nuclear import of these proteins following exit from mitosis is critical for establishment of the G1 nuclear environment. Dysregulation of post-mitotic nuclear import may affect the fate of newly divided stem or progenitor cells and may lead to cancer. Acute promyelocytic leukemia (APL) is a malignant disorder that involves a defect in blood cell differentiation at the promyelocytic stage. Recent studies suggest that pharmacological concentrations of the APL therapeutic drugs, all-trans retinoic acid (ATRA) and arsenic trioxide (ATO), affect post-mitotic nuclear import of the APL-associated oncoprotein PML/RARA. In the present study, we have investigated the possibility that ATRA and ATO affect post-mitotic nuclear import through interference with components of the nuclear import machinery. We observe reduced density and impaired integrity of nuclear pore complexes after ATRA and/or ATO exposure. Using a post-mitotic nuclear import assay, we demonstrate distinct import kinetics among different nuclear import pathways while nuclear import rates were similar in the presence or absence of APL therapeutic drugs.
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Affiliation(s)
- Anna Lång
- Department of Medical Biochemistry and Department of Microbiology, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Postboks 1171 Blindern, 0318 Oslo, Norway.
| | - Alexander Øye
- Department of Medical Biochemistry and Department of Microbiology, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway.
| | - Jens Eriksson
- Department of Medical Biochemistry and Department of Microbiology, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway.
| | - Alexander D Rowe
- Department of Medical Biochemistry and Department of Microbiology, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; Norwegian National Unit for Newborn Screening, Division for Pediatric and Adolescent Medicine, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway.
| | - Emma Lång
- Department of Medical Biochemistry and Department of Microbiology, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway.
| | - Stig Ove Bøe
- Department of Medical Biochemistry and Department of Microbiology, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway.
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Cutler AA, Jackson JB, Corbett AH, Pavlath GK. Non-equivalence of nuclear import among nuclei in multinucleated skeletal muscle cells. J Cell Sci 2018; 131:jcs.207670. [PMID: 29361530 DOI: 10.1242/jcs.207670] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 12/21/2017] [Indexed: 01/01/2023] Open
Abstract
Skeletal muscle is primarily composed of large myofibers containing thousands of post-mitotic nuclei distributed throughout a common cytoplasm. Protein production and localization in specialized myofiber regions is crucial for muscle function. Myonuclei differ in transcriptional activity and protein accumulation, but how these differences among nuclei sharing a cytoplasm are achieved is unknown. Regulated nuclear import of proteins is one potential mechanism for regulating transcription spatially and temporally in individual myonuclei. The best-characterized nuclear localization signal (NLS) in proteins is the classical NLS (cNLS), but many other NLS motifs exist. We examined cNLS and non-cNLS reporter protein import using multinucleated muscle cells generated in vitro, revealing that cNLS and non-cNLS nuclear import differs among nuclei in the same cell. Investigation of cNLS nuclear import rates in isolated myofibers ex vivo confirmed differences in nuclear import rates among myonuclei. Analyzing nuclear import throughout myogenesis revealed that cNLS and non-cNLS import varies during differentiation. Taken together, our results suggest that both spatial and temporal regulation of nuclear import pathways are important in muscle cell differentiation and protein regionalization in myofibers.
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Affiliation(s)
- Alicia A Cutler
- Department of Pharmacology, Emory University, Atlanta, GA 30322, USA.,Graduate Program in Biochemistry, Cell and Developmental Biology, Emory University, Atlanta, GA 30322, USA
| | | | - Anita H Corbett
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Grace K Pavlath
- Department of Pharmacology, Emory University, Atlanta, GA 30322, USA
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45
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Cytoplasmic transport and nuclear import of plasmid DNA. Biosci Rep 2017; 37:BSR20160616. [PMID: 29054961 PMCID: PMC5705778 DOI: 10.1042/bsr20160616] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 10/13/2017] [Accepted: 10/17/2017] [Indexed: 01/04/2023] Open
Abstract
Productive transfection and gene transfer require not simply the entry of DNA into cells and subsequent transcription from an appropriate promoter, but also a number of intracellular events that allow the DNA to move from the extracellular surface of the cell into and through the cytoplasm, and ultimately across the nuclear envelope and into the nucleus before any transcription can initiate. Immediately upon entry into the cytoplasm, naked DNA, either delivered through physical techniques or after disassembly of DNA-carrier complexes, associates with a large number of cellular proteins that mediate subsequent interactions with the microtubule network for movement toward the microtubule organizing center and the nuclear envelope. Plasmids then enter the nucleus either upon the mitotic disassembly of the nuclear envelope or through nuclear pore complexes in the absence of cell division, using a different set of proteins. This review will discuss our current understanding of these pathways used by naked DNA during the transfection process. While much has been elucidated on these processes, much remains to be discerned, but with the development of a number of model systems and approaches, great progress is being made.
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Idica A, Sevrioukov EA, Zisoulis DG, Hamdorf M, Daugaard I, Kadandale P, Pedersen IM. MicroRNA miR-128 represses LINE-1 (L1) retrotransposition by down-regulating the nuclear import factor TNPO1. J Biol Chem 2017; 292:20494-20508. [PMID: 28974576 DOI: 10.1074/jbc.m117.807677] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 09/20/2017] [Indexed: 01/04/2023] Open
Abstract
Repetitive elements, including LINE-1 (L1), comprise approximately half of the human genome. These elements can potentially destabilize the genome by initiating their own replication and reintegration into new sites (retrotransposition). In somatic cells, transcription of L1 elements is repressed by distinct molecular mechanisms, including DNA methylation and histone modifications, to repress transcription. Under conditions of hypomethylation (e.g. in tumor cells), a window of opportunity for L1 derepression arises, and additional restriction mechanisms become crucial. We recently demonstrated that the microRNA miR-128 represses L1 activity by directly binding to L1 ORF2 RNA. In this study, we tested whether miR-128 can also control L1 activity by repressing cellular proteins important for L1 retrotransposition. We found that miR-128 targets the 3' UTR of nuclear import factor transportin 1 (TNPO1) mRNA. Manipulation of miR-128 and TNPO1 levels demonstrated that induction or depletion of TNPO1 affects L1 retrotransposition and nuclear import of an L1-ribonucleoprotein complex (using L1-encoded ORF1p as a proxy for L1-ribonucleoprotein complexes). Moreover, TNPO1 overexpression partially reversed the repressive effect of miR-128 on L1 retrotransposition. Our study represents the first description of a protein factor involved in nuclear import of the L1 element and demonstrates that miR-128 controls L1 activity in somatic cells through two independent mechanisms: direct binding to L1 RNA and regulation of a cellular factor necessary for L1 nuclear import and retrotransposition.
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Affiliation(s)
- Adam Idica
- From the Department of Molecular Biology and Biochemistry, Francisco J. Ayala School of Biological Sciences, University of California, Irvine, California 92697
| | - Evgueni A Sevrioukov
- From the Department of Molecular Biology and Biochemistry, Francisco J. Ayala School of Biological Sciences, University of California, Irvine, California 92697
| | - Dimitrios G Zisoulis
- From the Department of Molecular Biology and Biochemistry, Francisco J. Ayala School of Biological Sciences, University of California, Irvine, California 92697
| | - Matthias Hamdorf
- From the Department of Molecular Biology and Biochemistry, Francisco J. Ayala School of Biological Sciences, University of California, Irvine, California 92697
| | - Iben Daugaard
- From the Department of Molecular Biology and Biochemistry, Francisco J. Ayala School of Biological Sciences, University of California, Irvine, California 92697
| | - Pavan Kadandale
- From the Department of Molecular Biology and Biochemistry, Francisco J. Ayala School of Biological Sciences, University of California, Irvine, California 92697
| | - Irene M Pedersen
- From the Department of Molecular Biology and Biochemistry, Francisco J. Ayala School of Biological Sciences, University of California, Irvine, California 92697
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Satoh R, Hagihara K, Sugiura R. Rae1-mediated nuclear export of Rnc1 is an important determinant in controlling MAPK signaling. Curr Genet 2017; 64:103-108. [PMID: 28799069 DOI: 10.1007/s00294-017-0732-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/08/2017] [Accepted: 08/08/2017] [Indexed: 01/24/2023]
Abstract
In eukaryotic cells, RNA binding proteins (RBPs) play critical roles in regulating almost every aspect of gene expression, often shuttling between the nucleus and the cytoplasm. They are also key determinants in cell fate via controlling the target mRNAs under the regulation of various signaling pathways in response to environmental stresses. Therefore, understanding the mechanisms that couple the location of mRNA and RBPs is a major challenge in the field of gene expression and signal responses. In fission yeast, a KH-type RBP Rnc1 negatively regulates MAPK signaling activation via mRNA stabilization of the dual-specificity MAPK phosphatase Pmp1, which dephosphorylates MAPK Pmk1. Rnc1 also serves as a target of MAPK phosphorylation, which makes a feedback loop mediated by an RBP. We recently discovered that the nuclear export of Rnc1 requires mRNA-binding ability and the mRNA export factor Rae1. This strongly suggested the presence of an mRNA-export system, which recognizes the mRNA/RBP complex and dictates the location and post-transcriptional regulation of mRNA cargo. Here, we briefly review the known mechanisms of general nuclear transporting systems, with an emphasis on our recent findings on the spatial regulation of Rnc1 and its impact on the regulation of the MAPK signal transduction cascade.
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Affiliation(s)
- Ryosuke Satoh
- Laboratory of Molecular Pharmacogenomics, Department of Pharmaceutical Sciences, Kindai University, Higashiosaka City, Osaka, 577-8502, Japan
| | - Kanako Hagihara
- Laboratory of Molecular Pharmacogenomics, Department of Pharmaceutical Sciences, Kindai University, Higashiosaka City, Osaka, 577-8502, Japan
| | - Reiko Sugiura
- Laboratory of Molecular Pharmacogenomics, Department of Pharmaceutical Sciences, Kindai University, Higashiosaka City, Osaka, 577-8502, Japan.
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Harnessing yeast organelles for metabolic engineering. Nat Chem Biol 2017; 13:823-832. [DOI: 10.1038/nchembio.2429] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 05/23/2016] [Indexed: 11/08/2022]
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49
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Alternative splicing regulates distinct subcellular localization of Epithelial splicing regulatory protein 1 (Esrp1) isoforms. Sci Rep 2017. [PMID: 28634384 PMCID: PMC5478600 DOI: 10.1038/s41598-017-03180-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Epithelial-Splicing-Regulatory-Protein 1 (Esrp1) is a cell-type specific RNA-binding protein (RBP) that is essential for mammalian development through maintenance of epithelial cell properties including barrier function. Esrp1 also regulates splicing during the epithelial to mesenchymal transition (EMT). It contains three highly conserved RNA recognition motifs (RRMs) in the absence of other clearly defined protein domains. Esrp1 itself is also alternatively spliced to produce multiple protein isoforms. Here we determined that two competing alternative 5' splice sites in exon 12 yield Esrp1 isoforms with differential nucleocytoplasmic localization. We carried out a detailed characterization of the Esrp1 peptide that is sufficient to confer nuclear localization. Furthermore, we identified splice variants encoding distinct nuclear and cytoplasmic isoforms of fusilli, the D. Melanogaster Esrp1 ortholog. Our observations demonstrate that the production of both nuclear and cytoplasmic Esrp1 isoforms through alternative splicing is phylogenetically conserved; strongly suggesting it is biologically significant. Thus, while previous studies have described extensive regulation by nuclear Esrp1 to promote epithelial specific splicing, it will be of great interest to study the contribution of cytoplasmic Esrp1 in maintenance of epithelial cell functions.
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50
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ADAR1 controls apoptosis of stressed cells by inhibiting Staufen1-mediated mRNA decay. Nat Struct Mol Biol 2017; 24:534-543. [PMID: 28436945 PMCID: PMC5461201 DOI: 10.1038/nsmb.3403] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 03/27/2017] [Indexed: 01/10/2023]
Abstract
Both p150 and p110 isoforms of ADAR1 convert adenosine to inosine in double-stranded RNA (dsRNA). ADAR1p150 suppresses the dsRNA sensing mechanism that activates MDA5-MAVS-IFN signaling in the cytoplasm. In contrast, the biological function of the ADAR1p110 isoform, usually located in the nucleus, remains largely unknown. Here we show that stress-activated phosphorylation of ADAR1p110 by MKK6-p38-MSK MAP kinases promotes its binding to Exportin-5 and export from the nucleus. Once translocated to the cytoplasm, ADAR1p110 suppresses apoptosis of stressed cells by protecting many anti-apoptotic gene transcripts that contain 3′UTR dsRNA structures primarily made from inverted Alu repeats. ADAR1p110 competitively inhibits binding of Staufen1 to the 3′UTR dsRNAs and antagonizes the Staufen1-mediated mRNA decay. Our studies revealed a new stress response mechanism, in which human ADAR1p110 and Staufen1 regulate surveillance of a set of mRNAs required for survival of stressed cells.
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