1
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Burdet V, Bournonville L, Das M, Wenger E, Delattre M, Steiner FA, Guichard P, Hamel V. Ultrastructure Expansion Microscopy applied to C. elegans embryos. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001033. [PMID: 38774216 PMCID: PMC11106672 DOI: 10.17912/micropub.biology.001033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 05/01/2024] [Accepted: 05/02/2024] [Indexed: 05/24/2024]
Abstract
Visualization of organelles using expansion microscopy has been previously applied to Caenorhadbitis elegans adult gonads or worms. However, its application to embryos has remained a challenge due to the protective eggshell barrier. Here, by combining freeze-cracking and ultrastructure expansion microscopy (U-ExM), we demonstrate a four-time isotropic expansion of C. elegans embryos. As an example structure, we chose the nuclear pore and demonstrate that we achieve sufficient resolution to distinguish them individually. Our work provides proof of principle for U-ExM in C. elegans embryos, which will be applicable for imaging a wide range of cellular structures in this model system.
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Affiliation(s)
- Valentin Burdet
- Molecular and Cellular Biology Department, University of Geneva, Switzerland
| | - Lorène Bournonville
- Molecular and Cellular Biology Department, University of Geneva, Switzerland
| | - Moushumi Das
- Molecular and Cellular Biology Department, University of Geneva, Switzerland
| | - Eva Wenger
- Ecole Normale Supérieure de Lyon, Laboratory of Biology and Modeling of the Cell, CNRS UMR5239, Inserm U1293, University Claude Bernard Lyon 1, 69007 Lyon, France
| | - Marie Delattre
- Ecole Normale Supérieure de Lyon, Laboratory of Biology and Modeling of the Cell, CNRS UMR5239, Inserm U1293, University Claude Bernard Lyon 1, 69007 Lyon, France
| | - Florian A. Steiner
- Molecular and Cellular Biology Department, University of Geneva, Switzerland
| | - Paul Guichard
- Molecular and Cellular Biology Department, University of Geneva, Switzerland
| | - Virginie Hamel
- Molecular and Cellular Biology Department, University of Geneva, Switzerland
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2
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Nkombo Nkoula S, Velez-Aguilera G, Ossareh-Nazari B, Van Hove L, Ayuso C, Legros V, Chevreux G, Thomas L, Seydoux G, Askjaer P, Pintard L. Mechanisms of nuclear pore complex disassembly by the mitotic Polo-like kinase 1 (PLK-1) in C. elegans embryos. SCIENCE ADVANCES 2023; 9:eadf7826. [PMID: 37467327 PMCID: PMC10355831 DOI: 10.1126/sciadv.adf7826] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 06/16/2023] [Indexed: 07/21/2023]
Abstract
The nuclear envelope, which protects and organizes the genome, is dismantled during mitosis. In the Caenorhabditis elegans zygote, nuclear envelope breakdown (NEBD) of the parental pronuclei is spatially and temporally regulated during mitosis to promote the unification of the maternal and paternal genomes. Nuclear pore complex (NPC) disassembly is a decisive step of NEBD, essential for nuclear permeabilization. By combining live imaging, biochemistry, and phosphoproteomics, we show that NPC disassembly is a stepwise process that involves Polo-like kinase 1 (PLK-1)-dependent and -independent steps. PLK-1 targets multiple NPC subcomplexes, including the cytoplasmic filaments, central channel, and inner ring. PLK-1 is recruited to and phosphorylates intrinsically disordered regions (IDRs) of several multivalent linker nucleoporins. Notably, although the phosphosites are not conserved between human and C. elegans nucleoporins, they are located in IDRs in both species. Our results suggest that targeting IDRs of multivalent linker nucleoporins is an evolutionarily conserved driver of NPC disassembly during mitosis.
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Affiliation(s)
- Sylvia Nkombo Nkoula
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
- Programme Équipe Labellisée Ligue contre le Cancer, Paris, France
| | - Griselda Velez-Aguilera
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
- Programme Équipe Labellisée Ligue contre le Cancer, Paris, France
| | - Batool Ossareh-Nazari
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
- Programme Équipe Labellisée Ligue contre le Cancer, Paris, France
| | - Lucie Van Hove
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
- Programme Équipe Labellisée Ligue contre le Cancer, Paris, France
| | - Cristina Ayuso
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, Seville, Spain
| | - Véronique Legros
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
| | - Guillaume Chevreux
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
| | - Laura Thomas
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Géraldine Seydoux
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, Seville, Spain
| | - Lionel Pintard
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013 Paris, France
- Programme Équipe Labellisée Ligue contre le Cancer, Paris, France
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3
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Thomas L, Taleb Ismail B, Askjaer P, Seydoux G. Nucleoporin foci are stress-sensitive condensates dispensable for C. elegans nuclear pore assembly. EMBO J 2023:e112987. [PMID: 37254647 DOI: 10.15252/embj.2022112987] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 05/02/2023] [Accepted: 05/10/2023] [Indexed: 06/01/2023] Open
Abstract
Nucleoporins (Nups) assemble nuclear pores that form the permeability barrier between nucleoplasm and cytoplasm. Nucleoporins also localize in cytoplasmic foci proposed to function as pore pre-assembly intermediates. Here, we characterize the composition and incidence of cytoplasmic Nup foci in an intact animal, C. elegans. We find that, in young non-stressed animals, Nup foci only appear in developing sperm, oocytes and embryos, tissues that express high levels of nucleoporins. The foci are condensates of highly cohesive FG repeat-containing nucleoporins (FG-Nups), which are maintained near their solubility limit in the cytoplasm by posttranslational modifications and chaperone activity. Only a minor fraction of FG-Nup molecules concentrate in Nup foci, which dissolve during M phase and are dispensable for nuclear pore assembly. Nucleoporin condensation is enhanced by stress and advancing age, and overexpression of a single FG-Nup in post-mitotic neurons is sufficient to induce ectopic condensation and organismal paralysis. We speculate that Nup foci are non-essential and potentially toxic condensates whose assembly is actively suppressed in healthy cells.
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Affiliation(s)
- Laura Thomas
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Basma Taleb Ismail
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, Seville, Spain
| | - Geraldine Seydoux
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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4
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Nkoula SN, Velez-Aguilera G, Ossareh-Nazari B, Hove LV, Ayuso C, Legros V, Chevreux G, Thomas L, Seydoux G, Askjaer P, Pintard L. Mechanisms of Nuclear Pore Complex disassembly by the mitotic Polo-Like Kinase 1 (PLK-1) in C. elegans embryos. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.21.528438. [PMID: 36865292 PMCID: PMC9980100 DOI: 10.1101/2023.02.21.528438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The nuclear envelope, which protects and organizes the interphase genome, is dismantled during mitosis. In the C. elegans zygote, nuclear envelope breakdown (NEBD) of the parental pronuclei is spatially and temporally regulated during mitosis to promote the unification of the parental genomes. During NEBD, Nuclear Pore Complex (NPC) disassembly is critical for rupturing the nuclear permeability barrier and removing the NPCs from the membranes near the centrosomes and between the juxtaposed pronuclei. By combining live imaging, biochemistry, and phosphoproteomics, we characterized NPC disassembly and unveiled the exact role of the mitotic kinase PLK-1 in this process. We show that PLK-1 disassembles the NPC by targeting multiple NPC sub-complexes, including the cytoplasmic filaments, the central channel, and the inner ring. Notably, PLK-1 is recruited to and phosphorylates intrinsically disordered regions of several multivalent linker nucleoporins, a mechanism that appears to be an evolutionarily conserved driver of NPC disassembly during mitosis. (149/150 words). One-Sentence Summary PLK-1 targets intrinsically disordered regions of multiple multivalent nucleoporins to dismantle the nuclear pore complexes in the C. elegans zygote.
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5
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Fragoso-Luna A, Romero-Bueno R, Eibl M, Ayuso C, Muñoz-Jiménez C, Benes V, Cases I, Askjaer P. Expanded FLP toolbox for spatiotemporal protein degradation and transcriptomic profiling in Caenorhabditis elegans. Genetics 2022; 223:6793861. [PMID: 36321973 PMCID: PMC9836023 DOI: 10.1093/genetics/iyac166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/24/2022] [Indexed: 11/05/2022] Open
Abstract
Control of gene expression in specific tissues and/or at certain stages of development allows the study and manipulation of gene function with high precision. Site-specific genome recombination by the flippase (FLP) and cyclization recombination (Cre) enzymes has proved particularly relevant. Joint efforts of many research groups have led to the creation of efficient FLP and Cre drivers to regulate gene expression in a variety of tissues in Caenorhabditis elegans. Here, we extend this toolkit by the addition of FLP lines that drive recombination specifically in distal tip cells, the somatic gonad, coelomocytes, and the epithelial P lineage. In some cases, recombination-mediated gene knockouts do not completely deplete protein levels due to persistence of long-lived proteins. To overcome this, we developed a spatiotemporally regulated degradation system for green fluorescent fusion proteins based on FLP-mediated recombination. Using 2 stable nuclear pore proteins, MEL-28/ELYS and NPP-2/NUP85 as examples, we report the benefit of combining tissue-specific gene knockout and protein degradation to achieve complete protein depletion. We also demonstrate that FLP-mediated recombination can be utilized to identify transcriptomes in a C. elegans tissue of interest. We have adapted RNA polymerase DamID for the FLP toolbox and by focusing on a well-characterized tissue, the hypodermis, we show that the vast majority of genes identified by RNA polymerase DamID are known to be expressed in this tissue. These tools allow combining FLP activity for simultaneous gene inactivation and transcriptomic profiling, thus enabling the inquiry of gene function in various complex biological processes.
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Affiliation(s)
| | | | | | - Cristina Ayuso
- Andalusian Centre for Developmental Biology, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Pablo de Olavide, Junta de Andalucía, 41013 Sevilla, Spain
| | - Celia Muñoz-Jiménez
- Andalusian Centre for Developmental Biology, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Pablo de Olavide, Junta de Andalucía, 41013 Sevilla, Spain
| | | | - Ildefonso Cases
- Andalusian Centre for Developmental Biology, Consejo Superior de Investigaciones Científicas (CSIC), Universidad Pablo de Olavide, Junta de Andalucía, 41013 Sevilla, Spain
| | - Peter Askjaer
- Corresponding author: Andalusian Centre for Developmental Biology, Gene Regulation and Morphogenesis, CSIC—Universidad Pablo de Olavide, Carretera de Utrera, km 1, 41013 Seville, Spain.
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6
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Mauro MS, Celma G, Zimyanin V, Magaj MM, Gibson KH, Redemann S, Bahmanyar S. Ndc1 drives nuclear pore complex assembly independent of membrane biogenesis to promote nuclear formation and growth. eLife 2022; 11:75513. [PMID: 35852146 PMCID: PMC9296133 DOI: 10.7554/elife.75513] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 06/15/2022] [Indexed: 01/19/2023] Open
Abstract
The nuclear envelope (NE) assembles and grows from bilayer lipids produced at the endoplasmic reticulum (ER). How ER membrane incorporation coordinates with assembly of nuclear pore complexes (NPCs) to generate a functional NE is not well understood. Here, we use the stereotypical first division of the early C. elegans embryo to test the role of the membrane-associated nucleoporin Ndc1 in coupling NPC assembly to NE formation and growth. 3D-EM tomography of reforming and expanded NEs establishes that Ndc1 determines NPC density. Loss of ndc1 results in faster turnover of the outer scaffold nucleoporin Nup160 at the NE, providing an explanation for how Ndc1 controls NPC number. NE formation fails in the absence of both Ndc1 and the inner ring component Nup53, suggesting partially redundant roles in NPC assembly. Importantly, upregulation of membrane synthesis restored the slow rate of nuclear growth resulting from loss of ndc1 but not from loss of nup53. Thus, membrane biogenesis can be decoupled from Ndc1-mediated NPC assembly to promote nuclear growth. Together, our data suggest that Ndc1 functions in parallel with Nup53 and membrane biogenesis to control NPC density and nuclear size.
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Affiliation(s)
- Michael Sean Mauro
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew HavenUnited States
| | - Gunta Celma
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew HavenUnited States
| | - Vitaly Zimyanin
- Center for Membrane and Cell Physiology, University of VirginiaCharlottesvilleUnited States,Department of Molecular Physiology and Biological Physics, University of Virginia, School of MedicineCharlottesvilleUnited States
| | - Magdalena M Magaj
- Center for Membrane and Cell Physiology, University of VirginiaCharlottesvilleUnited States,Department of Molecular Physiology and Biological Physics, University of Virginia, School of MedicineCharlottesvilleUnited States
| | - Kimberley H Gibson
- Center for Cellular and Molecular Imaging: Electron Microscopy, Department of Cell Biology, Yale School of MedicineNew HavenUnited States
| | - Stefanie Redemann
- Center for Membrane and Cell Physiology, University of VirginiaCharlottesvilleUnited States,Department of Molecular Physiology and Biological Physics, University of Virginia, School of MedicineCharlottesvilleUnited States,Department of Cell Biology, University of VirginiaCharlottesvilleUnited States
| | - Shirin Bahmanyar
- Department of Molecular, Cellular and Developmental Biology, Yale UniversityNew HavenUnited States
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7
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de la Cruz Ruiz P, Romero-Bueno R, Askjaer P. Analysis of Nuclear Pore Complexes in Caenorhabditis elegans by Live Imaging and Functional Genomics. Methods Mol Biol 2022; 2502:161-182. [PMID: 35412238 DOI: 10.1007/978-1-0716-2337-4_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Nuclear pore complexes (NPCs) are essential to communication of macromolecules between the cell nucleus and the surrounding cytoplasm. RNA synthesized in the nucleus is exported through NPCs to function in the cytoplasm, whereas transcription factors and other proteins are selectively and actively imported. In addition, many NPC constituents, known as nuclear pore proteins (nucleoporins or nups), also play critical roles in other processes, such as genome organization, gene expression, and kinetochore function. Thanks to its genetic amenability and transparent body, the nematode Caenorhabditis elegans is an attractive model to study NPC dynamics. We provide here an overview of available genome engineered strains and FLP/Frt-based tools to study tissue-specific functions of individual nucleoporins. We also present protocols for live imaging of fluorescently tagged nucleoporins in intact tissues of embryos, larvae, and adult and for analysis of interactions between nucleoporins and chromatin by DamID.
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Affiliation(s)
- Patricia de la Cruz Ruiz
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, Seville, Spain
| | - Raquel Romero-Bueno
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, Seville, Spain
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, Seville, Spain.
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8
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Zheleva A, Camino LP, Fernández-Fernández N, García-Rubio M, Askjaer P, García-Muse T, Aguilera A. THSC/TREX-2 deficiency causes replication stress and genome instability in Caenorhabditis elegans. J Cell Sci 2021; 134:jcs258435. [PMID: 34553761 PMCID: PMC10658913 DOI: 10.1242/jcs.258435] [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: 01/19/2021] [Accepted: 09/11/2021] [Indexed: 11/20/2022] Open
Abstract
Transcription is an essential process of DNA metabolism, yet it makes DNA more susceptible to DNA damage. THSC/TREX-2 is a conserved eukaryotic protein complex with a key role in mRNP biogenesis and maturation that prevents genome instability. One source of such instability is linked to transcription, as shown in yeast and human cells, but the underlying mechanism and whether this link is universal is still unclear. To obtain further insight into the putative role of the THSC/TREX-2 complex in genome integrity, we have used Caenorhabditis elegans mutants of the thp-1 and dss-1 components of THSC/TREX-2. These mutants show similar defective meiosis, DNA damage accumulation and activation of the DNA damage checkpoint. However, they differ from each other regarding replication defects, as determined by measuring dUTP incorporation in the germline. Interestingly, this specific thp-1 mutant phenotype can be partially rescued by overexpression of RNase H. Furthermore, both mutants show a mild increase in phosphorylation of histone H3 at Ser10 (H3S10P), a mark previously shown to be linked to DNA-RNA hybrid-mediated genome instability. These data support the view that both THSC/TREX-2 factors prevent transcription-associated DNA damage derived from DNA-RNA hybrid accumulation by separate means.
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Affiliation(s)
- Angelina Zheleva
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, 41092 Seville, Spain
| | - Lola P. Camino
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, 41092 Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Nuria Fernández-Fernández
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, 41092 Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - María García-Rubio
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, 41092 Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Peter Askjaer
- Centro Andaluz de Biología del Desarrollo (CABD), Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Tatiana García-Muse
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, 41092 Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
| | - Andrés Aguilera
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, 41092 Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
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9
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Garcia YA, Velasquez EF, Gao LW, Gholkar AA, Clutario KM, Cheung K, Williams-Hamilton T, Whitelegge JP, Torres JZ. Mapping Proximity Associations of Core Spindle Assembly Checkpoint Proteins. J Proteome Res 2021; 20:3414-3427. [PMID: 34087075 PMCID: PMC8256817 DOI: 10.1021/acs.jproteome.0c00941] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Indexed: 12/25/2022]
Abstract
The spindle assembly checkpoint (SAC) is critical for sensing defective microtubule-kinetochore attachments and tension across the kinetochore and functions to arrest cells in prometaphase to allow time to repair any errors before proceeding into anaphase. Dysregulation of the SAC leads to chromosome segregation errors that have been linked to human diseases like cancer. Although much has been learned about the composition of the SAC and the factors that regulate its activity, the proximity associations of core SAC components have not been explored in a systematic manner. Here, we have taken a BioID2-proximity-labeling proteomic approach to define the proximity protein environment for each of the five core SAC proteins BUB1, BUB3, BUBR1, MAD1L1, and MAD2L1 in mitotic-enriched populations of cells where the SAC is active. These five protein association maps were integrated to generate a SAC proximity protein network that contains multiple layers of information related to core SAC protein complexes, protein-protein interactions, and proximity associations. Our analysis validated many known SAC complexes and protein-protein interactions. Additionally, it uncovered new protein associations, including the ELYS-MAD1L1 interaction that we have validated, which lend insight into the functioning of core SAC proteins and highlight future areas of investigation to better understand the SAC.
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Affiliation(s)
- Yenni A. Garcia
- Department of Chemistry and Biochemistry,
University of California, Los Angeles, California 90095,
United States
| | - Erick F. Velasquez
- Department of Chemistry and Biochemistry,
University of California, Los Angeles, California 90095,
United States
| | - Lucy W. Gao
- Pasarow Mass Spectrometry Laboratory, The Jane and
Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of
Medicine, University of California, Los Angeles, California
90095, United States
| | - Ankur A. Gholkar
- Department of Chemistry and Biochemistry,
University of California, Los Angeles, California 90095,
United States
| | - Kevin M. Clutario
- Department of Chemistry and Biochemistry,
University of California, Los Angeles, California 90095,
United States
| | - Keith Cheung
- Department of Chemistry and Biochemistry,
University of California, Los Angeles, California 90095,
United States
| | - Taylor Williams-Hamilton
- Department of Chemistry and Biochemistry,
University of California, Los Angeles, California 90095,
United States
| | - Julian P. Whitelegge
- Pasarow Mass Spectrometry Laboratory, The Jane and
Terry Semel Institute for Neuroscience and Human Behavior, David Geffen School of
Medicine, University of California, Los Angeles, California
90095, United States
- Molecular Biology Institute, University of
California, Los Angeles, California 90095, United
States
- Jonsson Comprehensive Cancer Center,
University of California, Los Angeles, California 90095,
United States
| | - Jorge Z. Torres
- Department of Chemistry and Biochemistry,
University of California, Los Angeles, California 90095,
United States
- Molecular Biology Institute, University of
California, Los Angeles, California 90095, United
States
- Jonsson Comprehensive Cancer Center,
University of California, Los Angeles, California 90095,
United States
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10
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Zhang Y, Mou Y, Liang C, Zhu S, Liu S, Shao P, Li J, Wang Z. Promoting cell proliferation, cell cycle progression, and glycolysis: Glycometabolism-related genes act as prognostic signatures for prostate cancer. Prostate 2021; 81:157-169. [PMID: 33338276 DOI: 10.1002/pros.24092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/27/2020] [Accepted: 11/16/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND The Warburg effect seen in most solid tumors occurs only in the late stages of prostate cancer (PCa). Currently, the management of patients with low-risk localized PCa and patients after radical therapy remains a challenge. Our objective here was to evaluate glycometabolism-related genes as prognostic signatures for PCa. METHODS The International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA) databases and glycometabolism-related gene sets were obtained online. Glycometabolic prognostic signatures were identified and validated in a TCGA cohort and tested in an ICGC cohort. We used the gene set enrichment analysis to reveal biological processes associated with the glycometabolism-related signatures. Novel glycometabolism-related genes were selected for verifying their oncogenic phenotypes in vitro. RESULTS Two glycometabolic prognostic signatures were applied respectively to construct risk score formulas for PCa. Survival and receiver operating characteristic curve analyses were performed to detect the value of these prognostic signatures. We performed univariate and multivariate Cox regression analyses in the TCGA cohort, demonstrating the independence of the prognostic signatures. Three glycometabolism-related genes were found to be novel PCa-associated genes. These were shown to affect proliferation, cell cycle progression, and glycolysis of DU145 and PC3 cells in different degrees. CONCLUSION The present research represents the first glycometabolic and high-throughput investigation on PCa, revealing potential biomarkers and treatment targets. We confirm the vital role of glycometabolism in PCa and provide essential resources for future exploration of metabolism in PCa.
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Affiliation(s)
- Yao Zhang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
| | - Yanhua Mou
- Department of Radiation Oncology, Hubei Cancer Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Chao Liang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
| | - Shenhao Zhu
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
| | - Shouyong Liu
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
| | - Pengfei Shao
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
| | - Jie Li
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
| | - Zengjun Wang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China
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11
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Steroid hormones sulfatase inactivation extends lifespan and ameliorates age-related diseases. Nat Commun 2021; 12:49. [PMID: 33397961 PMCID: PMC7782729 DOI: 10.1038/s41467-020-20269-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 11/19/2020] [Indexed: 02/06/2023] Open
Abstract
Aging and fertility are two interconnected processes. From invertebrates to mammals, absence of the germline increases longevity. Here we show that loss of function of sul-2, the Caenorhabditis elegans steroid sulfatase (STS), raises the pool of sulfated steroid hormones, increases longevity and ameliorates protein aggregation diseases. This increased longevity requires factors involved in germline-mediated longevity (daf-16, daf-12, kri-1, tcer-1 and daf-36 genes) although sul-2 mutations do not affect fertility. Interestingly, sul-2 is only expressed in sensory neurons, suggesting a regulation of sulfated hormones state by environmental cues. Treatment with the specific STS inhibitor STX64, as well as with testosterone-derived sulfated hormones reproduces the longevity phenotype of sul-2 mutants. Remarkably, those treatments ameliorate protein aggregation diseases in C. elegans, and STX64 also Alzheimer’s disease in a mammalian model. These results open the possibility of reallocating steroid sulfatase inhibitors or derivates for the treatment of aging and aging related diseases. Sul-2 is a steroid sulfatase in c.elegans. Here the authors show that, in the absence of sul-2 enzymatic activity, worm lifespan is increased, and that chemical inhibition ameliorates symptoms of neurodegenerative disorders in worms and mice.
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12
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Vishnoi N, Dhanasekeran K, Chalfant M, Surovstev I, Khokha MK, Lusk CP. Differential turnover of Nup188 controls its levels at centrosomes and role in centriole duplication. J Cell Biol 2020; 219:133835. [PMID: 32211895 PMCID: PMC7055002 DOI: 10.1083/jcb.201906031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 11/18/2019] [Accepted: 01/09/2020] [Indexed: 02/07/2023] Open
Abstract
NUP188 encodes a scaffold component of the nuclear pore complex (NPC) and has been implicated as a congenital heart disease gene through an ill-defined function at centrioles. Here, we explore the mechanisms that physically and functionally segregate Nup188 between the pericentriolar material (PCM) and NPCs. Pulse-chase fluorescent labeling indicates that Nup188 populates centrosomes with newly synthesized protein that does not exchange with NPCs even after mitotic NPC breakdown. In addition, the steady-state levels of Nup188 are controlled by the sensitivity of the PCM pool, but not the NPC pool, to proteasomal degradation. Proximity-labeling and super-resolution microscopy show that Nup188 is vicinal to the inner core of the interphase centrosome. Consistent with this, we demonstrate direct binding between Nup188 and Cep152. We further show that Nup188 functions in centriole duplication at or upstream of Sas6 loading. Together, our data establish Nup188 as a component of PCM needed to duplicate the centriole with implications for congenital heart disease mechanisms.
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Affiliation(s)
- Nidhi Vishnoi
- Department of Cell Biology, Yale School of Medicine, New Haven, CT
| | | | | | - Ivan Surovstev
- Department of Cell Biology, Yale School of Medicine, New Haven, CT
| | - Mustafa K Khokha
- Pediatric Genomics Discovery Program, Departments of Pediatrics and Genetics, Yale School of Medicine, New Haven, CT
| | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT
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Platani M, Samejima I, Samejima K, Kanemaki MT, Earnshaw WC. Seh1 targets GATOR2 and Nup153 to mitotic chromosomes. J Cell Sci 2018; 131:jcs.213140. [PMID: 29618633 PMCID: PMC5992584 DOI: 10.1242/jcs.213140] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 03/23/2018] [Indexed: 12/27/2022] Open
Abstract
In metazoa, the Nup107 complex (also known as the nucleoporin Y-complex) plays a major role in formation of the nuclear pore complex in interphase and is localised to kinetochores in mitosis. The Nup107 complex shares a single highly conserved subunit, Seh1 (also known as SEH1L in mammals) with the GATOR2 complex, an essential activator of mTORC1 kinase. mTORC1/GATOR2 has a central role in the coordination of cell growth and proliferation. Here, we use chemical genetics and quantitative chromosome proteomics to study the role of the Seh1 protein in mitosis. Surprisingly, Seh1 is not required for the association of the Nup107 complex with mitotic chromosomes, but it is essential for the association of both the GATOR2 complex and nucleoporin Nup153 with mitotic chromosomes. Our analysis also reveals a role for Seh1 at human centromeres, where it is required for efficient localisation of the chromosomal passenger complex (CPC). Furthermore, this analysis detects a functional interaction between the Nup107 complex and the small kinetochore protein SKAP (also known as KNSTRN). Highlighted Article: The nucleoporin Seh1 is essential for the association of both the GATOR2 complex and the nucleoporin Nup153, but not the Nup107 complex, with mitotic chromosomes.
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Affiliation(s)
- Melpomeni Platani
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Itaru Samejima
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Kumiko Samejima
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Masato T Kanemaki
- Division of Molecular Cell Engineering, National Institute of Genetics, ROIS, and Department of Genetics, SOKENDAI, Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | - William C Earnshaw
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
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Muñoz-Jiménez C, Ayuso C, Dobrzynska A, Torres-Mendéz A, Ruiz PDLC, Askjaer P. An Efficient FLP-Based Toolkit for Spatiotemporal Control of Gene Expression in Caenorhabditis elegans. Genetics 2017; 206:1763-1778. [PMID: 28646043 PMCID: PMC5560786 DOI: 10.1534/genetics.117.201012] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 06/19/2017] [Indexed: 02/07/2023] Open
Abstract
Site-specific recombinases are potent tools to regulate gene expression. In particular, the Cre (cyclization recombination) and FLP (flipase) enzymes are widely used to either activate or inactivate genes in a precise spatiotemporal manner. Both recombinases work efficiently in the popular model organism Caenorhabditis elegans, but their use in this nematode is still only sporadic. To increase the utility of the FLP system in C. elegans, we have generated a series of single-copy transgenic strains that stably express an optimized version of FLP in specific tissues or by heat induction. We show that recombination efficiencies reach 100% in several cell types, such as muscles, intestine, and serotonin-producing neurons. Moreover, we demonstrate that most promoters drive recombination exclusively in the expected tissues. As examples of the potentials of the FLP lines, we describe novel tools for induced cell ablation by expression of the PEEL-1 toxin and a versatile FLP-out cassette for generation of GFP-tagged conditional knockout alleles. Together with other recombinase-based reagents created by the C. elegans community, this toolkit increases the possibilities for detailed analyses of specific biological processes at developmental stages inside intact animals.
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Affiliation(s)
- Celia Muñoz-Jiménez
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Cristina Ayuso
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Agnieszka Dobrzynska
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Antonio Torres-Mendéz
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Patricia de la Cruz Ruiz
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
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Hattersley N, Cheerambathur D, Moyle M, Stefanutti M, Richardson A, Lee KY, Dumont J, Oegema K, Desai A. A Nucleoporin Docks Protein Phosphatase 1 to Direct Meiotic Chromosome Segregation and Nuclear Assembly. Dev Cell 2017; 38:463-77. [PMID: 27623381 DOI: 10.1016/j.devcel.2016.08.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 07/10/2016] [Accepted: 08/13/2016] [Indexed: 12/31/2022]
Abstract
During M-phase entry in metazoans with open mitosis, the concerted action of mitotic kinases disassembles nuclei and promotes assembly of kinetochores-the primary microtubule attachment sites on chromosomes. At M-phase exit, these major changes in cellular architecture must be reversed. Here, we show that the conserved kinetochore-localized nucleoporin MEL-28/ELYS docks the catalytic subunit of protein phosphatase 1 (PP1c) to direct kinetochore disassembly-dependent chromosome segregation during oocyte meiosis I and nuclear assembly during the transition from M phase to interphase. During oocyte meiosis I, MEL-28-PP1c disassembles kinetochores in a timely manner to promote elongation of the acentrosomal spindles that segregate homologous chromosomes. During nuclear assembly, MEL-28 recruits PP1c to the periphery of decondensed chromatin, where it directs formation of a functional nuclear compartment. Thus, a pool of phosphatase activity associated with a kinetochore-localized nucleoporin contributes to two key events that occur during M-phase exit in metazoans: kinetochore disassembly and nuclear reassembly.
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Affiliation(s)
- Neil Hattersley
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0653, USA
| | - Dhanya Cheerambathur
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0653, USA
| | - Mark Moyle
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0653, USA
| | - Marine Stefanutti
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Amelia Richardson
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0653, USA
| | - Kian-Yong Lee
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0653, USA
| | - Julien Dumont
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Karen Oegema
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0653, USA
| | - Arshad Desai
- Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0653, USA.
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Ferreira J, Stear JH, Saumweber H. Nucleoporins NPP-10, NPP-13 and NPP-20 are required for HCP-4 nuclear import to establish correct centromere assembly. J Cell Sci 2017; 130:963-974. [PMID: 28122936 DOI: 10.1242/jcs.196709] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 01/13/2017] [Indexed: 12/15/2022] Open
Abstract
Centromeres form a chromosomal platform for the assembly of the kinetochores, which are required for orderly chromosome segregation. Assembly of both centromeres and kinetochores proceeds by a step-by-step mechanism that is regulated in time and space. It has been suggested that the regulated nuclear import of centromeric proteins is involved in this process. We show that the knockdown of nucleoporins NPP-10, NPP-13 and NPP-20 in Caenorhabditiselegans affects early steps in centromere formation and sister centromere resolution, and results in severe chromosomal defects in the early embryo. These phenotypes mirror the knockdown phenotype of HCP-4 (an ortholog of mammalian CENP-C), a key factor for centromere formation and inner kinetochore assembly. HCP-4 is present in the cytoplasm during interphase. It is imported into nuclei and assembled in centromeres during prophase. Following the knockdown of NPP-10, NPP-13 and NPP-20, HCP-4 remains in the cytosol throughout prophase due to stalled import. In prometaphase and later mitotic stages after breakdown of the nuclear envelope, HCP-4 is not incorporated into centromeres. These results indicate that correct timing of the availability of HCP-4 by nuclear import is essential.
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Affiliation(s)
- Jorge Ferreira
- Cytogenetics group, Institute of Biology, Humboldt-Universität zu Berlin, Chausseestr. 117, Berlin 10115, Germany
| | - Jeffrey H Stear
- University of New South Wales, School of Medical Sciences, Sydney, New South Wales 2052, Australia
| | - Harald Saumweber
- Cytogenetics group, Institute of Biology, Humboldt-Universität zu Berlin, Chausseestr. 117, Berlin 10115, Germany
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17
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Cohen-Fix O, Askjaer P. Cell Biology of the Caenorhabditis elegans Nucleus. Genetics 2017; 205:25-59. [PMID: 28049702 PMCID: PMC5216270 DOI: 10.1534/genetics.116.197160] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 11/09/2016] [Indexed: 12/25/2022] Open
Abstract
Studies on the Caenorhabditis elegans nucleus have provided fascinating insight to the organization and activities of eukaryotic cells. Being the organelle that holds the genetic blueprint of the cell, the nucleus is critical for basically every aspect of cell biology. The stereotypical development of C. elegans from a one cell-stage embryo to a fertile hermaphrodite with 959 somatic nuclei has allowed the identification of mutants with specific alterations in gene expression programs, nuclear morphology, or nuclear positioning. Moreover, the early C. elegans embryo is an excellent model to dissect the mitotic processes of nuclear disassembly and reformation with high spatiotemporal resolution. We review here several features of the C. elegans nucleus, including its composition, structure, and dynamics. We also discuss the spatial organization of chromatin and regulation of gene expression and how this depends on tight control of nucleocytoplasmic transport. Finally, the extensive connections of the nucleus with the cytoskeleton and their implications during development are described. Most processes of the C. elegans nucleus are evolutionarily conserved, highlighting the relevance of this powerful and versatile model organism to human biology.
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Affiliation(s)
- Orna Cohen-Fix
- Laboratory of Molecular and Cellular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Peter Askjaer
- Andalusian Center for Developmental Biology, Consejo Superior de Investigaciones Científicas/Junta de Andalucia/Universidad Pablo de Olavide, 41013 Seville, Spain
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18
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Gómez-Saldivar G, Fernandez A, Hirano Y, Mauro M, Lai A, Ayuso C, Haraguchi T, Hiraoka Y, Piano F, Askjaer P. Identification of Conserved MEL-28/ELYS Domains with Essential Roles in Nuclear Assembly and Chromosome Segregation. PLoS Genet 2016; 12:e1006131. [PMID: 27341616 PMCID: PMC4920428 DOI: 10.1371/journal.pgen.1006131] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Accepted: 05/26/2016] [Indexed: 11/19/2022] Open
Abstract
Nucleoporins are the constituents of nuclear pore complexes (NPCs) and are essential regulators of nucleocytoplasmic transport, gene expression and genome stability. The nucleoporin MEL-28/ELYS plays a critical role in post-mitotic NPC reassembly through recruitment of the NUP107-160 subcomplex, and is required for correct segregation of mitotic chromosomes. Here we present a systematic functional and structural analysis of MEL-28 in C. elegans early development and human ELYS in cultured cells. We have identified functional domains responsible for nuclear envelope and kinetochore localization, chromatin binding, mitotic spindle matrix association and chromosome segregation. Surprisingly, we found that perturbations to MEL-28’s conserved AT-hook domain do not affect MEL-28 localization although they disrupt MEL-28 function and delay cell cycle progression in a DNA damage checkpoint-dependent manner. Our analyses also uncover a novel meiotic role of MEL-28. Together, these results show that MEL-28 has conserved structural domains that are essential for its fundamental roles in NPC assembly and chromosome segregation. Most animal cells have a nucleus that contains the genetic material: the chromosomes. The nucleus is enclosed by the nuclear envelope, which provides a physical barrier between the chromosomes and the surrounding cytoplasm, and enables precisely controlled transport of proteins into and out of the nucleus. Transport occurs through nuclear pore complexes, which consist of multiple copies of ~30 different proteins called nucleoporins. Although the composition of nuclear pore complexes is known, the mechanisms of their assembly and function are still unclear. We have analyzed the nucleoporin MEL-28/ELYS through a systematic dissection of functional domains both in the nematode Caenorhabditis elegans and in human cells. Interestingly, MEL-28/ELYS localizes not only to nuclear pore complexes, but is also associated with chromosomal structures known as kinetochores during cell division. Our studies have revealed that even small perturbations in MEL-28/ELYS can have dramatic consequences on nuclear pore complex assembly as well as on separation of chromosomes during cell division. Surprisingly, inhibition of MEL-28/ELYS causes cell-cycle delay, suggesting activation of a cellular surveillance system for chromosomal damages. Finally, we conclude that the structural domains of MEL-28/ELYS are conserved from nematodes to humans.
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Affiliation(s)
- Georgina Gómez-Saldivar
- Andalusian Center for Developmental Biology (CABD), CSIC/Junta de Andalucia/Universidad Pablo de Olavide, Seville, Spain
| | - Anita Fernandez
- Biology Department, Fairfield University, Fairfield, Connecticut, United States of America
- * E-mail: (AF); (PA)
| | - Yasuhiro Hirano
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Michael Mauro
- Biology Department, Fairfield University, Fairfield, Connecticut, United States of America
| | - Allison Lai
- Biology Department, Fairfield University, Fairfield, Connecticut, United States of America
| | - Cristina Ayuso
- Andalusian Center for Developmental Biology (CABD), CSIC/Junta de Andalucia/Universidad Pablo de Olavide, Seville, Spain
| | - Tokuko Haraguchi
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, Kobe, Japan
| | - Yasushi Hiraoka
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
- Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, Kobe, Japan
| | - Fabio Piano
- Department of Biology and Center for Genomics and Systems Biology, New York University, New York, New York, United States of America
- New York University, Abu Dhabi, United Arab Emirates
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/Junta de Andalucia/Universidad Pablo de Olavide, Seville, Spain
- * E-mail: (AF); (PA)
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19
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Norflus F, Bu J, Guyton E, Gutekunst CA. Behavioral analysis of the huntingtin-associated protein 1 ortholog trak-1 in Caenorhabditis elegans. J Neurosci Res 2016; 94:850-6. [PMID: 27319755 DOI: 10.1002/jnr.23756] [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: 11/21/2015] [Revised: 04/04/2016] [Accepted: 04/04/2016] [Indexed: 11/06/2022]
Abstract
The precise role of huntingtin-associated protein 1 (HAP1) is not known, but studies have shown that it is important for early development and survival. A Caenorhabditis elegans ortholog of HAP1, T27A3.1 (also called trak-1), has been found and is expressed in a subset of neurons. Potential behavioral functions of three knockout lines of T27A3.1 were examined. From its suspected role in mice we hypothesize that T27A3.1 might be involved in egg hatching and early growth, mechanosensation, chemosensation, sensitivity to osmolarity, and synaptic transmission. Our studies show that the knockout worms are significantly different from the wild-type (WT) worms only in the synaptic transmission test, which was measured by adding aldicarb, an acetylcholinesterase inhibitor. The change in function was determined by measuring the number of worms paralyzed. However, when the T27A3.1 worms were tested for egg hatching and early growth, mechanosensation, chemosensation, and sensitivity to osmolarity, there were no significant differences between the knockout and WT worms. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Fran Norflus
- Department of Biology, Clayton State University, Morrow, Georgia
| | - Jingnan Bu
- Department of Neurosurgery, Emory University, Atlanta, Georgia
| | - Evon Guyton
- Department of Biology, Clayton State University, Morrow, Georgia
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20
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Complex Commingling: Nucleoporins and the Spindle Assembly Checkpoint. Cells 2015; 4:706-25. [PMID: 26540075 PMCID: PMC4695854 DOI: 10.3390/cells4040706] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 10/12/2015] [Accepted: 10/28/2015] [Indexed: 12/14/2022] Open
Abstract
The segregation of the chromosomes during mitosis is an important process, in which the replicated DNA content is properly allocated into two daughter cells. To ensure their genomic integrity, cells present an essential surveillance mechanism known as the spindle assembly checkpoint (SAC), which monitors the bipolar attachment of the mitotic spindle to chromosomes to prevent errors that would result in chromosome mis-segregation and aneuploidy. Multiple components of the nuclear pore complex (NPC), a gigantic protein complex that forms a channel through the nuclear envelope to allow nucleocytoplasmic exchange of macromolecules, were shown to be critical for faithful cell division and implicated in the regulation of different steps of the mitotic process, including kinetochore and spindle assembly as well as the SAC. In this review, we will describe current knowledge about the interconnection between the NPC and the SAC in an evolutional perspective, which primarily relies on the two mitotic checkpoint regulators, Mad1 and Mad2. We will further discuss the role of NPC constituents, the nucleoporins, in kinetochore and spindle assembly and the formation of the mitotic checkpoint complex during mitosis and interphase.
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21
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Rahman MM, Munzig M, Kaneshiro K, Lee B, Strome S, Müller-Reichert T, Cohen-Fix O. Caenorhabditis elegans polo-like kinase PLK-1 is required for merging parental genomes into a single nucleus. Mol Biol Cell 2015; 26:4718-35. [PMID: 26490119 PMCID: PMC4678026 DOI: 10.1091/mbc.e15-04-0244] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 10/13/2015] [Indexed: 11/11/2022] Open
Abstract
Before the first zygotic division, the nuclear envelopes of the maternal and paternal pronuclei disassemble, allowing both sets of chromosomes to be incorporated into a single nucleus in daughter cells after mitosis. We found that in Caenorhabditis elegans, partial inactivation of the polo-like kinase PLK-1 causes the formation of two nuclei, containing either the maternal or paternal chromosomes, in each daughter cell. These two nuclei gave rise to paired nuclei in all subsequent cell divisions. The paired-nuclei phenotype was caused by a defect in forming a gap in the nuclear envelopes at the interface between the two pronuclei during the first mitotic division. This was accompanied by defects in chromosome congression and alignment of the maternal and paternal metaphase plates relative to each other. Perturbing chromosome congression by other means also resulted in failure to disassemble the nuclear envelope between the two pronuclei. Our data further show that PLK-1 is needed for nuclear envelope breakdown during early embryogenesis. We propose that during the first zygotic division, PLK-1-dependent chromosome congression and metaphase plate alignment are necessary for the disassembly of the nuclear envelope between the two pronuclei, ultimately allowing intermingling of the maternal and paternal chromosomes.
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Affiliation(s)
- Mohammad M Rahman
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Mandy Munzig
- Structural Cell Biology Group, Experimental Center, Medical Faculty Carl Gustav Carus, University of Technology Dresden, 01307 Dresden, Germany
| | - Kiyomi Kaneshiro
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064
| | - Brandon Lee
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Susan Strome
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064
| | - Thomas Müller-Reichert
- Structural Cell Biology Group, Experimental Center, Medical Faculty Carl Gustav Carus, University of Technology Dresden, 01307 Dresden, Germany
| | - Orna Cohen-Fix
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
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22
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Yang HJ, Asakawa H, Haraguchi T, Hiraoka Y. Nup132 modulates meiotic spindle attachment in fission yeast by regulating kinetochore assembly. J Cell Biol 2015; 211:295-308. [PMID: 26483559 PMCID: PMC4621824 DOI: 10.1083/jcb.201501035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 09/11/2015] [Indexed: 02/06/2023] Open
Abstract
The fission yeast nucleoporin Nup132 is required for timely assembly of outer kinetochore proteins during meiotic prophase and its depletion activates the spindle assembly checkpoint in meiosis I, suggesting a role in establishing monopolar spindle attachment through outer kinetochore reorganization at meiotic prophase. During meiosis, the kinetochore undergoes substantial reorganization to establish monopolar spindle attachment. In the fission yeast Schizosaccharomyces pombe, the KNL1–Spc7-Mis12-Nuf2 (KMN) complex, which constitutes the outer kinetochore, is disassembled during meiotic prophase and is reassembled before meiosis I. Here, we show that the nucleoporin Nup132 is required for timely assembly of the KMN proteins: In the absence of Nup132, Mis12 and Spc7 are precociously assembled at the centromeres during meiotic prophase. In contrast, Nuf2 shows timely dissociation and reappearance at the meiotic centromeres. We further demonstrate that depletion of Nup132 activates the spindle assembly checkpoint in meiosis I, possibly because of the increased incidence of erroneous spindle attachment at sister chromatids. These results suggest that precocious assembly of the kinetochores leads to the meiosis I defects observed in the nup132-disrupted mutant. Thus, we propose that Nup132 plays an important role in establishing monopolar spindle attachment at meiosis I through outer kinetochore reorganization at meiotic prophase.
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Affiliation(s)
- Hui-Ju Yang
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| | - Haruhiko Asakawa
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| | - Tokuko Haraguchi
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, Iwaoka-cho, Nishi-ku, Kobe 651-2492, Japan
| | - Yasushi Hiraoka
- Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, Iwaoka-cho, Nishi-ku, Kobe 651-2492, Japan
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Bohr T, Nelson CR, Klee E, Bhalla N. Spindle assembly checkpoint proteins regulate and monitor meiotic synapsis in C. elegans. J Cell Biol 2015; 211:233-42. [PMID: 26483555 PMCID: PMC4621841 DOI: 10.1083/jcb.201409035] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 09/18/2015] [Indexed: 11/22/2022] Open
Abstract
Homologue synapsis is required for meiotic chromosome segregation, but how synapsis is initiated between chromosomes is poorly understood. In Caenorhabditis elegans, synapsis and a checkpoint that monitors synapsis depend on pairing centers (PCs), cis-acting loci that interact with nuclear envelope proteins, such as SUN-1, to access cytoplasmic microtubules. Here, we report that spindle assembly checkpoint (SAC) components MAD-1, MAD-2, and BUB-3 are required to negatively regulate synapsis and promote the synapsis checkpoint response. Both of these roles are independent of a conserved component of the anaphase-promoting complex, indicating a unique role for these proteins in meiotic prophase. MAD-1 and MAD-2 localize to the periphery of meiotic nuclei and interact with SUN-1, suggesting a role at PCs. Consistent with this idea, MAD-1 and BUB-3 require full PC function to inhibit synapsis. We propose that SAC proteins monitor the stability of pairing, or tension, between homologues to regulate synapsis and elicit a checkpoint response.
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Affiliation(s)
- Tisha Bohr
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064
| | - Christian R Nelson
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064
| | - Erin Klee
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064
| | - Needhi Bhalla
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064
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Abstract
Chromosomes are not only carriers of the genetic material, but also actively regulate the assembly of complex intracellular architectures. During mitosis, chromosome-induced microtubule polymerisation ensures spindle assembly in cells without centrosomes and plays a supportive role in centrosome-containing cells. Chromosomal signals also mediate post-mitotic nuclear envelope (NE) re-formation. Recent studies using novel approaches to manipulate histones in oocytes, where functions can be analysed in the absence of transcription, have established that nucleosomes, but not DNA alone, mediate the chromosomal regulation of spindle assembly and NE formation. Both processes require the generation of RanGTP by RCC1 recruited to nucleosomes but nucleosomes also acquire cell cycle stage specific regulators, Aurora B in mitosis and ELYS, the initiator of nuclear pore complex assembly, at mitotic exit. Here, we review the mechanisms by which nucleosomes control assembly and functions of the spindle and the NE, and discuss their implications for genome maintenance.
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Affiliation(s)
- Christian Zierhut
- Laboratory of Chromosome and Cell Biology, Rockefeller University, New York, NY, USA
| | - Hironori Funabiki
- Laboratory of Chromosome and Cell Biology, Rockefeller University, New York, NY, USA
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Lawrence KS, Chau T, Engebrecht J. DNA damage response and spindle assembly checkpoint function throughout the cell cycle to ensure genomic integrity. PLoS Genet 2015; 11:e1005150. [PMID: 25898113 PMCID: PMC4405263 DOI: 10.1371/journal.pgen.1005150] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 03/17/2015] [Indexed: 11/21/2022] Open
Abstract
Errors in replication or segregation lead to DNA damage, mutations, and aneuploidies. Consequently, cells monitor these events and delay progression through the cell cycle so repair precedes division. The DNA damage response (DDR), which monitors DNA integrity, and the spindle assembly checkpoint (SAC), which responds to defects in spindle attachment/tension during metaphase of mitosis and meiosis, are critical for preventing genome instability. Here we show that the DDR and SAC function together throughout the cell cycle to ensure genome integrity in C. elegans germ cells. Metaphase defects result in enrichment of SAC and DDR components to chromatin, and both SAC and DDR are required for metaphase delays. During persistent metaphase arrest following establishment of bi-oriented chromosomes, stability of the metaphase plate is compromised in the absence of DDR kinases ATR or CHK1 or SAC components, MAD1/MAD2, suggesting SAC functions in metaphase beyond its interactions with APC activator CDC20. In response to DNA damage, MAD2 and the histone variant CENPA become enriched at the nuclear periphery in a DDR-dependent manner. Further, depletion of either MAD1 or CENPA results in loss of peripherally associated damaged DNA. In contrast to a SAC-insensitive CDC20 mutant, germ cells deficient for SAC or CENPA cannot efficiently repair DNA damage, suggesting that SAC mediates DNA repair through CENPA interactions with the nuclear periphery. We also show that replication perturbations result in relocalization of MAD1/MAD2 in human cells, suggesting that the role of SAC in DNA repair is conserved. Checkpoints are surveillance pathways that monitor and correct cellular errors to ensure that the genome is transmitted intact through cell division; defects in checkpoints lead to human disease such as cancer. Two major checkpoint pathways that have been extensively studied are the DNA damage response and the spindle assembly checkpoint. As their names imply, they have been thought to monitor distinct chromosomal events during the cell cycle. Here, we used C. elegans proliferating germ cells and human cells to investigate the role of these checkpoints when either DNA is damaged or the spindle is perturbed. We discovered that these checkpoints function together in response to these different perturbations to ensure genome integrity. Our studies have important implications for cancer treatments, as many cancer chemotherapies target one of these checkpoint pathways without consideration for the effect on the other pathway.
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Affiliation(s)
- Katherine S. Lawrence
- Department of Molecular and Cellular Biology; Biochemistry, Molecular Cellular and Developmental Biology Graduate Group, University of California, Davis, Davis, California, United States of America
| | - Thinh Chau
- Department of Molecular and Cellular Biology; Biochemistry, Molecular Cellular and Developmental Biology Graduate Group, University of California, Davis, Davis, California, United States of America
| | - JoAnne Engebrecht
- Department of Molecular and Cellular Biology; Biochemistry, Molecular Cellular and Developmental Biology Graduate Group, University of California, Davis, Davis, California, United States of America
- * E-mail:
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26
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Gay S, Foiani M. Nuclear envelope and chromatin, lock and key of genome integrity. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 317:267-330. [PMID: 26008788 DOI: 10.1016/bs.ircmb.2015.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
More than as an inert separation between the inside and outside of the nucleus, the nuclear envelope (NE) constitutes an active toll, which controls the import and export of molecules, and also a hub for a diversity of genomic processes, such as transcription, DNA repair, and chromatin dynamics. Proteins localized at the inner surface of the NE (such as lamins, nuclear pore proteins, lamin-associated proteins) interact with chromatin in a dynamic manner, contributing to the establishment of topological domains. In this review, we address the complex interplay between chromatin and NE. We discuss the divergence of this cross talk during evolution and comment both on the current established models and the most recent findings. In particular, we focus our attention on how the NE cooperates with chromatin in protecting the genome integrity.
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Affiliation(s)
- Sophie Gay
- IFOM, the FIRC Institute of Molecular Oncology, Milan, Italy
| | - Marco Foiani
- IFOM, the FIRC Institute of Molecular Oncology, Milan, Italy; Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milan, Italy
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27
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Lawrence KS, Engebrecht J. The spindle assembly checkpoint: More than just keeping track of the spindle. TRENDS IN CELL & MOLECULAR BIOLOGY 2015; 10:141-150. [PMID: 27667906 PMCID: PMC5033511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Genome stability is essential for cell proliferation and survival. Consequently, genome integrity is monitored by two major checkpoints, the DNA damage response (DDR) and the spindle assembly checkpoint (SAC). The DDR monitors DNA lesions in G1, S, and G2 stages of the cell cycle and the SAC ensures proper chromosome segregation in M phase. There have been extensive studies characterizing the roles of these checkpoints in response to the processes for which they are named; however, emerging evidence suggests significant crosstalk between the checkpoints. Here we review recent findings demonstrating overlapping roles for the SAC and DDR in metaphase, and in response to DNA damage throughout the cell cycle.
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Affiliation(s)
- Katherine S. Lawrence
- Department of Molecular and Cellular Biology, University of California Davis, One Shields Ave, Davis, California 95616, USA
| | - JoAnne Engebrecht
- Department of Molecular and Cellular Biology, University of California Davis, One Shields Ave, Davis, California 95616, USA
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Morales-Martínez A, Dobrzynska A, Askjaer P. Inner nuclear membrane protein LEM-2 is required for proper nuclear separation and morphology. J Cell Sci 2015; 128:1090-6. [DOI: 10.1242/jcs.164202] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The inner nuclear membrane proteins emerin and LEMD2 have both overlapping and separate functions in regulation of nuclear organization, gene expression and cell differentiation. We report here that emerin/EMR-1 and LEMD2/LEM-2 are expressed in all tissues throughout Caenorhaditis elegans development but their relative distribution differs between cell types. The ratio between EMR-1 and LEM-2 is particularly high in contractile tissues, intermediate in neurons and hypodermis and lowest in intestine and germ line. We find that LEM-2 is recruited earlier than EMR-1 to reforming nuclear envelopes, suggesting the presence of separate mitotic membrane compartments and specific functions of each protein. Concordantly, we observe that nuclei of lem-2 mutant embryos, but not of emr-1 mutants, have reduced nuclear circularity. Finally, we uncover a novel role of LEM-2 in nuclear separation and anchoring of microtubule organizing centers.
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29
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Parry G. Components of the Arabidopsis nuclear pore complex play multiple diverse roles in control of plant growth. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:6057-67. [PMID: 25165147 PMCID: PMC4203139 DOI: 10.1093/jxb/eru346] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The nuclear pore complex (NPC) is a multisubunit protein conglomerate that facilitates movement of RNA and protein between the nucleus and cytoplasm. Relatively little is known regarding the influence of the Arabidopsis NPC on growth and development. Seedling development, flowering time, nuclear morphology, mRNA accumulation, and gene expression changes in Arabidopsis nucleoporin mutants were investigated. Nuclear export of mRNA is differentially affected in plants with defects in nucleoporins that lie in different NPC subcomplexes. This study reveals differences in the manner by which nucleoporins alter molecular and plant growth phenotypes, suggesting that nuclear pore subcomplexes play distinct roles in nuclear transport and reveal a possible feedback relationship between the expression of genes involved in nuclear transport.
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Affiliation(s)
- Geraint Parry
- Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, UK
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30
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Genome-wide analysis links emerin to neuromuscular junction activity in Caenorhabditis elegans. Genome Biol 2014; 15:R21. [PMID: 24490688 PMCID: PMC4053756 DOI: 10.1186/gb-2014-15-2-r21] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 02/03/2014] [Indexed: 01/01/2023] Open
Abstract
Background Laminopathies are diseases characterized by defects in nuclear envelope structure. A well-known example is Emery-Dreifuss muscular dystrophy, which is caused by mutations in the human lamin A/C and emerin genes. While most nuclear envelope proteins are ubiquitously expressed, laminopathies often affect only a subset of tissues. The molecular mechanisms underlying these tissue-specific manifestations remain elusive. We hypothesize that different functional subclasses of genes might be differentially affected by defects in specific nuclear envelope components. Results Here we determine genome-wide DNA association profiles of two nuclear envelope components, lamin/LMN-1 and emerin/EMR-1 in adult Caenorhabditis elegans. Although both proteins bind to transcriptionally inactive regions of the genome, EMR-1 is enriched at genes involved in muscle and neuronal function. Deletion of either EMR-1 or LEM-2, another integral envelope protein, causes local changes in nuclear architecture as evidenced by altered association between DNA and LMN-1. Transcriptome analyses reveal that EMR-1 and LEM-2 are associated with gene repression, particularly of genes implicated in muscle and nervous system function. We demonstrate that emr-1, but not lem-2, mutants are sensitive to the cholinesterase inhibitor aldicarb, indicating altered activity at neuromuscular junctions. Conclusions We identify a class of elements that bind EMR-1 but do not associate with LMN-1, and these are enriched for muscle and neuronal genes. Our data support a redundant function of EMR-1 and LEM-2 in chromatin anchoring to the nuclear envelope and gene repression. We demonstrate a specific role of EMR-1 in neuromuscular junction activity that may contribute to Emery-Dreifuss muscular dystrophy in humans.
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31
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Askjaer P, Galy V, Meister P. Modern Tools to Study Nuclear Pore Complexes and Nucleocytoplasmic Transport in Caenorhabditis elegans. Methods Cell Biol 2014; 122:277-310. [DOI: 10.1016/b978-0-12-417160-2.00013-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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32
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Li Z, Zhu Y, Zhai Y, R Castroagudin M, Bao Y, White TE, Glavy JS. Werner complex deficiency in cells disrupts the Nuclear Pore Complex and the distribution of lamin B1. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1833:3338-3345. [PMID: 24050918 DOI: 10.1016/j.bbamcr.2013.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 07/22/2013] [Accepted: 09/03/2013] [Indexed: 11/24/2022]
Abstract
From the surrounding shell to the inner machinery, nuclear proteins provide the functional plasticity of the nucleus. This study highlights the nuclear association of Pore membrane (POM) protein NDC1 and Werner protein (WRN), a RecQ helicase responsible for the DNA instability progeria disorder, Werner Syndrome. In our previous publication, we connected the DNA damage sensor Werner's Helicase Interacting Protein (WHIP), a binding partner of WRN, to the NPC. Here, we confirm the association of the WRN/WHIP complex and NDC1. In established WRN/WHIP knockout cell lines, we further demonstrate the interdependence of WRN/WHIP and Nucleoporins (Nups). These changes do not completely abrogate the barrier of the Nuclear Envelope (NE) but do affect the distribution of FG Nups and the RAN gradient, which are necessary for nuclear transport. Evidence from WRN/WHIP knockout cell lines demonstrates changes in the processing and nucleolar localization of lamin B1. The appearance of "RAN holes" void of RAN corresponds to regions within the nucleolus filled with condensed pools of lamin B1. From WRN/WHIP knockout cell line extracts, we found three forms of lamin B1 that correspond to mature holoprotein and two potential post-translationally modified forms of the protein. Upon treatment with topoisomerase inhibitors lamin B1 cleavage occurs only in WRN/WHIP knockout cells. Our data suggest the link of the NDC1 and WRN as one facet of the network between the nuclear periphery and genome stability. Loss of WRN complex leads to multiple alterations at the NPC and the nucleolus.
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Affiliation(s)
- Zhi Li
- Department of Chemistry, Chemical Biology & Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Yizhou Zhu
- Department of Chemistry, Chemical Biology & Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Yujia Zhai
- Department of Chemistry, Chemical Biology & Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Michelle R Castroagudin
- Department of Chemistry, Chemical Biology & Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Yifei Bao
- Department of Chemistry, Chemical Biology & Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Tommy E White
- Department of Chemistry, Chemical Biology & Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Joseph S Glavy
- Department of Chemistry, Chemical Biology & Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA.
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Ikegami K, Lieb JD. Integral nuclear pore proteins bind to Pol III-transcribed genes and are required for Pol III transcript processing in C. elegans. Mol Cell 2013; 51:840-9. [PMID: 24011592 DOI: 10.1016/j.molcel.2013.08.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 06/27/2013] [Accepted: 07/31/2013] [Indexed: 11/15/2022]
Abstract
Nuclear pores associate with active protein-coding genes in yeast and have been implicated in transcriptional regulation. Here, we show that in addition to transcriptional regulation, key components of C. elegans nuclear pores are required for processing of a subset of small nucleolar RNAs (snoRNAs) and tRNAs transcribed by RNA polymerase (Pol) III. Chromatin immunoprecipitation of NPP-13 and NPP-3, two integral nuclear pore components, and importin-β IMB-1 provides strong evidence that this requirement is direct. All three proteins associate specifically with tRNA and snoRNA genes undergoing Pol III transcription. These pore components bind immediately downstream of the Pol III preinitiation complex but are not required for Pol III recruitment. Instead, NPP-13 is required for cleavage of tRNA and snoRNA precursors into mature RNAs, whereas Pol II transcript processing occurs normally. Our data suggest that integral nuclear pore proteins act to coordinate transcription and processing of Pol III transcripts in C. elegans.
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Affiliation(s)
- Kohta Ikegami
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Carolina Center for Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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34
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Zheng X, Yang S, Han Y, Zhao X, Zhao L, Tian T, Tong J, Xu P, Xiong C, Meng A. Loss of zygotic NUP107 protein causes missing of pharyngeal skeleton and other tissue defects with impaired nuclear pore function in zebrafish embryos. J Biol Chem 2012; 287:38254-64. [PMID: 22965233 PMCID: PMC3488094 DOI: 10.1074/jbc.m112.408997] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 09/08/2012] [Indexed: 11/06/2022] Open
Abstract
The Nup107-160 multiprotein subcomplex is essential for the assembly of nuclear pore complexes. The developmental functions of individual constituents of this subcomplex in vertebrates remain elusive. In particular, it is unknown whether Nup107 plays an important role in development of vertebrate embryos. Zebrafish nup107 is maternally expressed and its zygotic expression becomes prominent in the head region and the intestine from 24 h postfertilization (hpf) onward. In this study, we generate a zebrafish mutant line, nup107(tsu068Gt), in which the nup107 locus is disrupted by an insertion of Tol2 transposon element in the first intron and as a result it fails to produce normal transcripts. Homozygous nup107(tsu068Gt) mutant embryos exhibit tissue-specific defects after 3 days postfertilization (dpf), including loss of the pharyngeal skeletons, degeneration of the intestine, absence of the swim bladder, and smaller eyes. These mutants die at 5-6 days. Extensive apoptosis occurs in the affected tissues, which is partially dependent on p53 apoptotic pathways. In cells of the defective tissues, FG-repeat nucleoporins are disturbed and nuclear pore number is reduced, leading to impaired translocation of mRNAs from the nucleus to the cytoplasm. Our findings shed new light on developmental function of Nup107 in vertebrates.
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Affiliation(s)
- Xiaofeng Zheng
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Shuyan Yang
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
- the Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yanchao Han
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Xinyi Zhao
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Long Zhao
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Tian Tian
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Jingyuan Tong
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Pengfei Xu
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Cong Xiong
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
| | - Anming Meng
- From the State Key Laboratory of Biomembrane and Membrane Engineering, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China and
- the Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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Hachet V, Busso C, Toya M, Sugimoto A, Askjaer P, Gönczy P. The nucleoporin Nup205/NPP-3 is lost near centrosomes at mitotic onset and can modulate the timing of this process in Caenorhabditis elegans embryos. Mol Biol Cell 2012; 23:3111-21. [PMID: 22740626 PMCID: PMC3418306 DOI: 10.1091/mbc.e12-03-0204] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Through an RNAi-based modifier screen, we identified the nucleoporin Nup205/NPP-3 as a negative regulator of mitotic onset in Caenorhabditis elegans. Strikingly, NPP-3 is lost from the nuclear envelope at mitotic onset in an AIR-1– and centrosome-dependent manner. We propose a model whereby centrosomes and AIR-1 promote timely mitosis by locally removing NPP-3. Regulation of mitosis in time and space is critical for proper cell division. We conducted an RNA interference–based modifier screen to identify novel regulators of mitosis in Caenorhabditis elegans embryos. Of particular interest, this screen revealed that the Nup205 nucleoporin NPP-3 can negatively modulate the timing of mitotic onset. Furthermore, we discovered that NPP-3 and nucleoporins that are associated with it are lost from the nuclear envelope (NE) in the vicinity of centrosomes at the onset of mitosis. We demonstrate that centrosomes are both necessary and sufficient for NPP-3 local loss, which also requires the activity of the Aurora-A kinase AIR-1. Our findings taken together support a model in which centrosomes and AIR-1 promote timely onset of mitosis by locally removing NPP-3 and associated nucleoporins from the NE.
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Affiliation(s)
- Virginie Hachet
- Swiss Institute for Experimental Cancer Research, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
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36
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González-Aguilera C, Askjaer P. Dissecting the NUP107 complex: multiple components and even more functions. Nucleus 2012; 3:340-8. [PMID: 22713280 DOI: 10.4161/nucl.21135] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The Nuclear Pore Complex (NPC) is a fascinating structure whose functional relevance and complexity attract significant interest. Within the NPC, several different subcomplexes interact with each other to form a highly conserved and stable structure. One of these subcomplexes is the NUP107 complex, constituted by 7-9 members. A wide variety of functions have been ascribed to the NUP107 complex, ranging from NPC assembly to mRNA export to cell differentiation. Recently, genetic dissection of the NUP107 complex has provided novel insight to the assembly of the complex and has, moreover, revealed an unexpected connection with the mitotic spindle assembly checkpoint protein MAD1.
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Affiliation(s)
- Cristina González-Aguilera
- Centro Andaluz de Biología del Desarrollo (CABD), Consejo Superior de Investigaciones Científicas, Universidad Pablo de Olavide, Seville, Spain
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37
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Clever M, Funakoshi T, Mimura Y, Takagi M, Imamoto N. The nucleoporin ELYS/Mel28 regulates nuclear envelope subdomain formation in HeLa cells. Nucleus 2012; 3:187-99. [PMID: 22555603 PMCID: PMC3383574 DOI: 10.4161/nucl.19595] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In open mitosis the nuclear envelope (NE) reassembles at the end of each mitosis. This process involves the reformation of the nuclear pore complex (NPC), the inner and outer nuclear membranes, and the nuclear lamina. In human cells cell cycle-dependent NE subdomains exist, characterized as A-type lamin-rich/NPC-free or B-type lamin-rich/NPC-rich, which are initially formed as core or noncore regions on mitotic chromosomes, respectively. Although postmitotic NE formation has been extensively studied, little is known about the coordination of NPC and NE assembly. Here, we report that the nucleoporin ELYS/Mel28, which is crucial for postmitotic NPC formation, is essential for recruiting the lamin B receptor (LBR) to the chromosomal noncore region. Furthermore, ELYS/Mel28 is responsible for focusing of A-type lamin-binding proteins like emerin, Lap2α and the barrier-to-autointegration factor (BAF) at the chromosomal core region. ELYS/Mel28 biochemically interacts with the LBR in a phosphorylation-dependent manner. Recruitment of the LBR depends on the nucleoporin Nup107, which interacts with ELYS/Mel28 but not on nucleoporin Pom121, suggesting that the specific molecular interactions with ELYS/Mel28 are involved in the NE assembly at the noncore region. The depletion of the LBR affected neither the behavior of emerin nor Lap2α indicating that the recruitment of the LBR to mitotic chromosomes is not involved in formation of the core region. The depletion of ELYS/Mel28 also accelerates the entry into cytokinesis after recruitment of emerin to chromosomes. Our data show that ELYS/Mel28 plays a role in NE subdomain formation in late mitosis.
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Affiliation(s)
- Michaela Clever
- Cellular Dynamics Laboratory; Riken Advanced Science Institute; Saitama, Japan
| | - Tomoko Funakoshi
- Cellular Dynamics Laboratory; Riken Advanced Science Institute; Saitama, Japan
- Live-Cell Molecular Imaging Research Team; Riken Advanced Science Institute; Saitama, Japan
| | - Yasuhiro Mimura
- Cellular Dynamics Laboratory; Riken Advanced Science Institute; Saitama, Japan
| | - Masatoshi Takagi
- Cellular Dynamics Laboratory; Riken Advanced Science Institute; Saitama, Japan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory; Riken Advanced Science Institute; Saitama, Japan
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