1
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Singh U, Bindra D, Samaiya A, Mishra RK. Overexpressed Nup88 stabilized through interaction with Nup62 promotes NF-κB dependent pathways in cancer. Front Oncol 2023; 13:1095046. [PMID: 36845732 PMCID: PMC9947638 DOI: 10.3389/fonc.2023.1095046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 01/16/2023] [Indexed: 02/11/2023] Open
Abstract
Bidirectional nucleo-cytoplasmic transport, regulating several vital cellular processes, is mediated by the Nuclear Pore Complex (NPC) comprising the nucleoporin (Nup) proteins. Nup88, a constituent nucleoporin, is overexpressed in many cancers, and a positive correlation exists between progressive stages of cancer and Nup88 levels. While a significant link of Nup88 overexpression in head and neck cancer exists but mechanistic details of Nup88 roles in tumorigenesis are sparse. Here, we report that Nup88 and Nup62 levels are significantly elevated in head and neck cancer patient samples and cell lines. We demonstrate that the elevated levels of Nup88 or Nup62 impart proliferation and migration advantages to cells. Interestingly, Nup88-Nup62 engage in a strong interaction independent of Nup-glycosylation status and cell-cycle stages. We report that the interaction with Nup62 stabilizes Nup88 by inhibiting the proteasome-mediated degradation of overexpressed Nup88. Overexpressed Nup88 stabilized by interaction with Nup62 can interact with NF-κB (p65) and sequesters p65 partly into nucleus of unstimulated cells. NF-κB targets like Akt, c-myc, IL-6 and BIRC3 promoting proliferation and growth are induced under Nup88 overexpression conditions. In conclusion, our data indicates that simultaneous overexpression of Nup62 and Nup88 in head and neck cancer stabilizes Nup88. Stabilized Nup88 interacts and activates p65 pathway, which perhaps is the underlying mechanism in Nup88 overexpressing tumors.
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Affiliation(s)
- Usha Singh
- Nups and Sumo Biology Group, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh, India
| | - Divya Bindra
- Nups and Sumo Biology Group, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh, India
| | - Atul Samaiya
- Department of Surgical Oncology, Bansal Hospital, Bhopal, Madhya Pradesh, India
| | - Ram Kumar Mishra
- Nups and Sumo Biology Group, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER), Bhopal, Madhya Pradesh, India,*Correspondence: Ram Kumar Mishra,
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2
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Gleixner AM, Verdone BM, Otte CG, Anderson EN, Ramesh N, Shapiro OR, Gale JR, Mauna JC, Mann JR, Copley KE, Daley EL, Ortega JA, Cicardi ME, Kiskinis E, Kofler J, Pandey UB, Trotti D, Donnelly CJ. NUP62 localizes to ALS/FTLD pathological assemblies and contributes to TDP-43 insolubility. Nat Commun 2022; 13:3380. [PMID: 35697676 PMCID: PMC9192689 DOI: 10.1038/s41467-022-31098-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 06/03/2022] [Indexed: 01/12/2023] Open
Abstract
A G4C2 hexanucleotide repeat expansion in the C9orf72 gene is the most common genetic cause of ALS and FTLD (C9-ALS/FTLD) with cytoplasmic TDP-43 inclusions observed in regions of neurodegeneration. The accumulation of repetitive RNAs and dipeptide repeat protein (DPR) are two proposed mechanisms of toxicity in C9-ALS/FTLD and linked to impaired nucleocytoplasmic transport. Nucleocytoplasmic transport is regulated by the phenylalanine-glycine nucleoporins (FG nups) that comprise the nuclear pore complex (NPC) permeability barrier. However, the relationship between FG nups and TDP-43 pathology remains elusive. Our studies show that nuclear depletion and cytoplasmic mislocalization of one FG nup, NUP62, is linked to TDP-43 mislocalization in C9-ALS/FTLD iPSC neurons. Poly-glycine arginine (GR) DPR accumulation initiates the formation of cytoplasmic RNA granules that recruit NUP62 and TDP-43. Cytoplasmic NUP62 and TDP-43 interactions promotes their insolubility and NUP62:TDP-43 inclusions are frequently found in C9orf72 ALS/FTLD as well as sporadic ALS/FTLD postmortem CNS tissue. Our findings indicate NUP62 cytoplasmic mislocalization contributes to TDP-43 proteinopathy in ALS/FTLD.
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Affiliation(s)
- Amanda M Gleixner
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Brandie Morris Verdone
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Charlton G Otte
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Physician Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Eric N Anderson
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Nandini Ramesh
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
- Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA
| | - Olivia R Shapiro
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Jenna R Gale
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Jocelyn C Mauna
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Jacob R Mann
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Katie E Copley
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
| | - Elizabeth L Daley
- The Ken & Ruth Davee Department of Neurology, Northwestern University of Feinberg School of Medicine, Chicago, IL, USA
| | - Juan A Ortega
- The Ken & Ruth Davee Department of Neurology, Northwestern University of Feinberg School of Medicine, Chicago, IL, USA
| | - Maria Elena Cicardi
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Evangelos Kiskinis
- The Ken & Ruth Davee Department of Neurology, Northwestern University of Feinberg School of Medicine, Chicago, IL, USA
- Department of Neuroscience, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Julia Kofler
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Udai B Pandey
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA
- Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Davide Trotti
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Christopher J Donnelly
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- LiveLikeLou Center for ALS Research, University of Pittsburgh Brain Institute, Pittsburgh, PA, USA.
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA.
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3
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Coyne AN, Rothstein JD. Nuclear pore complexes - a doorway to neural injury in neurodegeneration. Nat Rev Neurol 2022; 18:348-362. [PMID: 35488039 PMCID: PMC10015220 DOI: 10.1038/s41582-022-00653-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2022] [Indexed: 12/13/2022]
Abstract
The genetic underpinnings and end-stage pathological hallmarks of neurodegenerative diseases are increasingly well defined, but the cellular pathophysiology of disease initiation and propagation remains poorly understood, especially in sporadic forms of these diseases. Altered nucleocytoplasmic transport is emerging as a prominent pathomechanism of multiple neurodegenerative diseases, including amyotrophic lateral sclerosis, Alzheimer disease, frontotemporal dementia and Huntington disease. The nuclear pore complex (NPC) and interactions between its individual nucleoporin components and nuclear transport receptors regulate nucleocytoplasmic transport, as well as genome organization and gene expression. Specific nucleoporin abnormalities have been identified in sporadic and familial forms of neurodegenerative disease, and these alterations are thought to contribute to disrupted nucleocytoplasmic transport. The specific nucleoporins and nucleocytoplasmic transport proteins that have been linked to different neurodegenerative diseases are partially distinct, suggesting that NPC injury contributes to the cellular specificity of neurodegenerative disease and could be an early initiator of the pathophysiological cascades that underlie neurodegenerative disease. This concept is consistent with the fact that rare genetic mutations in some nucleoporins cause cell-type-specific neurological disease. In this Review, we discuss nucleoporin and NPC disruptions and consider their impact on cellular function and the pathophysiology of neurodegenerative disease.
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Affiliation(s)
- Alyssa N Coyne
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Jeffrey D Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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4
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One Ring to Rule them All? Structural and Functional Diversity in the Nuclear Pore Complex. Trends Biochem Sci 2021; 46:595-607. [PMID: 33563541 DOI: 10.1016/j.tibs.2021.01.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 02/07/2023]
Abstract
The nuclear pore complex (NPC) is the massive protein assembly that regulates the transport of macromolecules between the nucleus and the cytoplasm. Recent breakthroughs have provided major insights into the structure of the NPC in different eukaryotes, revealing a previously unsuspected diversity of NPC architectures. In parallel, the NPC has been shown to be a key player in regulating essential nuclear processes such as chromatin organization, gene expression, and DNA repair. However, our knowledge of the NPC structure has not been able to address the molecular mechanisms underlying its regulatory roles. We discuss potential explanations, including the coexistence of alternative NPC architectures with specific functional roles.
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5
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Coyne AN, Zaepfel BL, Hayes L, Fitchman B, Salzberg Y, Luo EC, Bowen K, Trost H, Aigner S, Rigo F, Yeo GW, Harel A, Svendsen CN, Sareen D, Rothstein JD. G 4C 2 Repeat RNA Initiates a POM121-Mediated Reduction in Specific Nucleoporins in C9orf72 ALS/FTD. Neuron 2020; 107:1124-1140.e11. [PMID: 32673563 PMCID: PMC8077944 DOI: 10.1016/j.neuron.2020.06.027] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 03/06/2020] [Accepted: 06/23/2020] [Indexed: 02/08/2023]
Abstract
Through mechanisms that remain poorly defined, defects in nucleocytoplasmic transport and accumulations of specific nuclear-pore-complex-associated proteins have been reported in multiple neurodegenerative diseases, including C9orf72 Amyotrophic Lateral Sclerosis and Frontotemporal Dementia (ALS/FTD). Using super-resolution structured illumination microscopy, we have explored the mechanism by which nucleoporins are altered in nuclei isolated from C9orf72 induced pluripotent stem-cell-derived neurons (iPSNs). Of the 23 nucleoporins evaluated, we observed a reduction in a subset of 8, including key components of the nuclear pore complex scaffold and the transmembrane nucleoporin POM121. Reduction in POM121 appears to initiate a decrease in the expression of seven additional nucleoporins, ultimately affecting the localization of Ran GTPase and subsequent cellular toxicity in C9orf72 iPSNs. Collectively, our data suggest that the expression of expanded C9orf72 ALS/FTD repeat RNA alone affects nuclear POM121 expression in the initiation of a pathological cascade affecting nucleoporin levels within neuronal nuclei and ultimately downstream neuronal survival.
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Affiliation(s)
- Alyssa N Coyne
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Benjamin L Zaepfel
- Biochemistry, Cellular, and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Lindsey Hayes
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Boris Fitchman
- Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Yuval Salzberg
- Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - En-Ching Luo
- Bioengineering Graduate Program, University of California San Diego College of Engineering, La Jolla, CA 92037, USA
| | - Kelly Bowen
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hannah Trost
- The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Stefan Aigner
- Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, CA 92037, USA
| | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA 92010, USA
| | - Gene W Yeo
- Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, CA 92037, USA; Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92037, USA
| | - Amnon Harel
- Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Clive N Svendsen
- The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Dhruv Sareen
- The Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Jeffrey D Rothstein
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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6
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The Nuclear Pore Complex: A Target for NS3 Protease of Dengue and Zika Viruses. Viruses 2020; 12:v12060583. [PMID: 32466480 PMCID: PMC7354628 DOI: 10.3390/v12060583] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/01/2020] [Accepted: 04/05/2020] [Indexed: 12/22/2022] Open
Abstract
During flavivirus infection, some viral proteins move to the nucleus and cellular components are relocated from the nucleus to the cytoplasm. Thus, the integrity of the main regulator of the nuclear-cytoplasmic transport, the nuclear pore complex (NPC), was evaluated during infection with dengue virus (DENV) and Zika virus (ZIKV). We found that while during DENV infection the integrity and distribution of at least three nucleoporins (Nup), Nup153, Nup98, and Nup62 were altered, during ZIKV infection, the integrity of TPR, Nup153, and Nup98 were modified. In this work, several lines of evidence indicate that the viral serine protease NS2B3 is involved in Nups cleavage. First, the serine protease inhibitors, TLCK and Leupeptin, prevented Nup98 and Nup62 cleavage. Second, the transfection of DENV and ZIKV NS2B3 protease was sufficient to inhibit the nuclear ring recognition detected in mock-infected cells with the Mab414 antibody. Third, the mutant but not the active (WT) protease was unable to cleave Nups in transfected cells. Thus, here we describe for the first time that the NS3 protein from flavivirus plays novel functions hijacking the nuclear pore complex, the main controller of the nuclear-cytoplasmic transport.
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7
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Bishop PJ, Kinoshita Y, Lopes NN, Ward AS, Kohtz DS. Changes in Nup62 content affect contact-induced differentiation of cultured myoblasts. Differentiation 2020; 114:27-35. [PMID: 32554220 DOI: 10.1016/j.diff.2020.05.001] [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: 10/01/2019] [Revised: 03/21/2020] [Accepted: 05/11/2020] [Indexed: 10/24/2022]
Abstract
Differentiation of cultured skeletal myoblasts is induced by extrinsic signals that include reduction in ambient mitogen concentration and increased cell density. Using an established murine myoblast cell line (C2C12), we have found that experimental reduction of the nucleoporin p62 (Nup62) content of myoblasts enhances differentiation in high-mitogen medium, while forced expression of Nup62 inhibits density-induced differentiation. In contrast, differentiation of myoblasts induced by low-mitogen medium was unaffected by ectopic Nup62 expression. Further analyses suggested that Nup62 content affects density-induced myoblast differentiation through a mechanism involving activation of p38 MAP kinase. Nuclear pore complex (NPC) composition, in particular changes in NUP62 content, may be altered during viral infection, differentiation, and in neoplastic growth. The results support a functional role for changes in Nup62 composition in NPCs and density-induced myogenic differentiation, and suggest a link between loss of Nup62 content and induction of an intracellular stress signaling pathways.
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Affiliation(s)
- Patrick J Bishop
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, MI, 48859, USA.
| | - Yayoi Kinoshita
- Department of Pathology, Icahn School of Medicine, One Gustave Levy Place, New York, NY, 10029, USA.
| | - N Natalie Lopes
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, MI, 48859, USA.
| | - Avery S Ward
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, MI, 48859, USA.
| | - D Stave Kohtz
- Foundational Sciences, College of Medicine, Central Michigan University, Mount Pleasant, MI, 48859, USA.
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8
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Shamseldin HE, Makhseed N, Ibrahim N, Al-Sheddi T, Alobeid E, Abdulwahab F, Alkuraya FS. NUP214 deficiency causes severe encephalopathy and microcephaly in humans. Hum Genet 2019; 138:221-229. [PMID: 30758658 DOI: 10.1007/s00439-019-01979-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 02/07/2019] [Indexed: 10/27/2022]
Abstract
Nuclear pore complex (NPC) is a fundamental component of the nuclear envelope and is key to the nucleocytoplasmic transport. Mutations in several NUP genes that encode individual components of NPC known as nucleoporins have been identified in recent years among patients with static encephalopathies characterized by developmental delay and microcephaly. We describe a multiplex consanguineous family in which four affected members presented with severe neonatal hypotonia, profound global developmental delay, progressive microcephaly and early death. Autozygome and linkage analysis revealed that this phenotype is linked to a founder disease haplotype (chr9:127,113,732-135,288,807) in which whole exome sequencing revealed the presence of a novel homozygous missense variant in NUP214. Functional analysis of patient-derived fibroblasts recapitulated the dysmorphic phenotype of nuclei that was previously described in NUP214 knockdown cells. In addition, the typical rim staining of NUP214 is largely displaced, further supporting the deleterious effect of the variant. Our data expand the list of NUP genes that are mutated in encephalopathy disorders in humans.
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Affiliation(s)
- Hanan E Shamseldin
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Nawal Makhseed
- Department of Pediatrics, Al-Jahra Hospital, Kuwait City, Kuwait
| | - Niema Ibrahim
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Tarfa Al-Sheddi
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Eman Alobeid
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Firdous Abdulwahab
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. .,Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia.
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9
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Cutler AA, Jackson JB, Corbett AH, Pavlath GK. Non-equivalence of nuclear import among nuclei in multinucleated skeletal muscle cells. J Cell Sci 2018; 131:jcs.207670. [PMID: 29361530 DOI: 10.1242/jcs.207670] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 12/21/2017] [Indexed: 01/01/2023] Open
Abstract
Skeletal muscle is primarily composed of large myofibers containing thousands of post-mitotic nuclei distributed throughout a common cytoplasm. Protein production and localization in specialized myofiber regions is crucial for muscle function. Myonuclei differ in transcriptional activity and protein accumulation, but how these differences among nuclei sharing a cytoplasm are achieved is unknown. Regulated nuclear import of proteins is one potential mechanism for regulating transcription spatially and temporally in individual myonuclei. The best-characterized nuclear localization signal (NLS) in proteins is the classical NLS (cNLS), but many other NLS motifs exist. We examined cNLS and non-cNLS reporter protein import using multinucleated muscle cells generated in vitro, revealing that cNLS and non-cNLS nuclear import differs among nuclei in the same cell. Investigation of cNLS nuclear import rates in isolated myofibers ex vivo confirmed differences in nuclear import rates among myonuclei. Analyzing nuclear import throughout myogenesis revealed that cNLS and non-cNLS import varies during differentiation. Taken together, our results suggest that both spatial and temporal regulation of nuclear import pathways are important in muscle cell differentiation and protein regionalization in myofibers.
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Affiliation(s)
- Alicia A Cutler
- Department of Pharmacology, Emory University, Atlanta, GA 30322, USA.,Graduate Program in Biochemistry, Cell and Developmental Biology, Emory University, Atlanta, GA 30322, USA
| | | | - Anita H Corbett
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Grace K Pavlath
- Department of Pharmacology, Emory University, Atlanta, GA 30322, USA
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10
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Ryabichko SS, Ibragimov AN, Lebedeva LA, Kozlov EN, Shidlovskii YV. Super-Resolution Microscopy in Studying the Structure and Function of the Cell Nucleus. Acta Naturae 2017; 9:42-51. [PMID: 29340216 PMCID: PMC5762827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Indexed: 11/21/2022] Open
Abstract
In recent decades, novel microscopic methods commonly referred to as super- resolution microscopy have been developed. These methods enable the visualization of a cell with a resolution of up to 10 nm. The application of these methods is of great interest in studying the structure and function of the cell nucleus. The review describes the main achievements in this field.
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Affiliation(s)
- S. S. Ryabichko
- Institute of Gene Biology RAS, Vavilova Str. 34/5, Moscow, 119334, Russia
| | - A. N. Ibragimov
- Institute of Gene Biology RAS, Vavilova Str. 34/5, Moscow, 119334, Russia
| | - L. A. Lebedeva
- Institute of Gene Biology RAS, Vavilova Str. 34/5, Moscow, 119334, Russia
| | - E. N. Kozlov
- Institute of Gene Biology RAS, Vavilova Str. 34/5, Moscow, 119334, Russia
| | - Y. V. Shidlovskii
- Institute of Gene Biology RAS, Vavilova Str. 34/5, Moscow, 119334, Russia
- I.M. Sechenov First Moscow State Medical University, Trubetskaya Str. 8, bldg. 2, Moscow, 119048 , Russia
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11
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Shashkova S, Leake MC. Single-molecule fluorescence microscopy review: shedding new light on old problems. Biosci Rep 2017; 37:BSR20170031. [PMID: 28694303 PMCID: PMC5520217 DOI: 10.1042/bsr20170031] [Citation(s) in RCA: 150] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 07/08/2017] [Accepted: 07/10/2017] [Indexed: 12/19/2022] Open
Abstract
Fluorescence microscopy is an invaluable tool in the biosciences, a genuine workhorse technique offering exceptional contrast in conjunction with high specificity of labelling with relatively minimal perturbation to biological samples compared with many competing biophysical techniques. Improvements in detector and dye technologies coupled to advances in image analysis methods have fuelled recent development towards single-molecule fluorescence microscopy, which can utilize light microscopy tools to enable the faithful detection and analysis of single fluorescent molecules used as reporter tags in biological samples. For example, the discovery of GFP, initiating the so-called 'green revolution', has pushed experimental tools in the biosciences to a completely new level of functional imaging of living samples, culminating in single fluorescent protein molecule detection. Today, fluorescence microscopy is an indispensable tool in single-molecule investigations, providing a high signal-to-noise ratio for visualization while still retaining the key features in the physiological context of native biological systems. In this review, we discuss some of the recent discoveries in the life sciences which have been enabled using single-molecule fluorescence microscopy, paying particular attention to the so-called 'super-resolution' fluorescence microscopy techniques in live cells, which are at the cutting-edge of these methods. In particular, how these tools can reveal new insights into long-standing puzzles in biology: old problems, which have been impossible to tackle using other more traditional tools until the emergence of new single-molecule fluorescence microscopy techniques.
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Affiliation(s)
- Sviatlana Shashkova
- Department of Physics, Biological Physical Sciences Institute (BPSI), University of York, York YO10 5DD, U.K
- Department of Biology, Biological Physical Sciences Institute (BPSI), University of York, York YO10 5DD, U.K
| | - Mark C Leake
- Department of Physics, Biological Physical Sciences Institute (BPSI), University of York, York YO10 5DD, U.K.
- Department of Biology, Biological Physical Sciences Institute (BPSI), University of York, York YO10 5DD, U.K
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12
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Wu Z, Jin Z, Zhang X, Shen N, Wang J, Zhao Y, Mei L. Nup62, associated with spindle microtubule rather than spindle matrix, is involved in chromosome alignment and spindle assembly during mitosis. Cell Biol Int 2016; 40:968-75. [PMID: 27298184 DOI: 10.1002/cbin.10633] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 06/01/2016] [Indexed: 11/10/2022]
Abstract
An increasing number of the active mitotic functions of nucleoporins in the distinct steps of mitosis have been assigned over the past few years. As one of FG-repeats containing nucleoporins, Nup62 has been found to be involved in nuclear transport, cell migration, virus infection, and cell cycle regulation. However, the role and mechanism of Nup62 in mitotic regulation have not been fully revealed. In this paper, it was revealed that a fraction of Nup62 was associated with mitotic spindle microtubule instead of spindle matrix, and the localization of Nup62 in the mitotic spindle depended on its three coiled-coil domains rather than Crm1, although Nup62 strongly interacted with Crm1 during mitosis. Moreover, depletion of Nup62 by small interference of RNA seriously induced the defects of chromosome alignment and spindle assembly although the bipolar spindle was observed in most of the Nup62 knock-down cells. Notably, congression of polar chromosome defect was observed in more than 30% of Nup62 knock-down cells. These findings revealed that Nup62 was a novel mitotic spindle associated nucleoporin and involved in chromosome alignment and spindle assembly.
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Affiliation(s)
- Zhige Wu
- Department of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
| | - Zhihua Jin
- Department of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
| | - Xinhong Zhang
- Department of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
| | - Na Shen
- Department of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
| | - Jinbo Wang
- Department of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
| | - Yingxian Zhao
- Department of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
| | - Lehe Mei
- Department of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
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Martins TV, Evans MJ, Wysham DB, Morris RJ. Nuclear pores enable sustained perinuclear calcium oscillations. BMC SYSTEMS BIOLOGY 2016; 10:55. [PMID: 27449670 PMCID: PMC4957432 DOI: 10.1186/s12918-016-0289-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 06/14/2016] [Indexed: 11/16/2022]
Abstract
Background Calcium signalling relies on the flux of calcium ions across membranes yet how signals in different compartments are related remains unclear. In particular, similar calcium signals on both sides of the nuclear envelope have been reported and attributed to passive diffusion through nuclear pores. However, observed differing cytosolic and nucleosolic calcium signatures suggest that the signalling machinery in these compartments can act independently. Results We adapt the fire-diffuse-fire model to investigate the generation of perinuclear calcium oscillations. We demonstrate that autonomous spatio-temporal calcium patterns are still possible in the presence of nuclear and cytosolic coupling via nuclear pores. The presence or absence of this autonomy is dependent upon the strength of the coupling and the maximum firing rate of an individual calcium channel. In all cases, coupling through the nuclear pores enables robust signalling with respect to changes in the diffusion constant. Conclusions We show that contradictory interpretations of experimental data with respect to the autonomy of nuclear calcium oscillations can be reconciled within one model, with different observations being a consequence of varying nuclear pore permeabilities for calcium and refractory conditions of channels. Furthermore, our results provide an explanation for why calcium oscillations on both sides of the nuclear envelope may be beneficial for sustained perinuclear signaling. Electronic supplementary material The online version of this article (doi:10.1186/s12918-016-0289-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Teresa Vaz Martins
- Computational & Systems Biology and Crop Genetics, John Innes Centre, Norwich Research Park, Norwich, UK.
| | - Matthew J Evans
- Computational & Systems Biology and Crop Genetics, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Derin B Wysham
- Mathematics Department, Wenatchee Valley College, Wenatchee, USA
| | - Richard J Morris
- Computational & Systems Biology and Crop Genetics, John Innes Centre, Norwich Research Park, Norwich, UK
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14
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Sydor AM, Czymmek KJ, Puchner EM, Mennella V. Super-Resolution Microscopy: From Single Molecules to Supramolecular Assemblies. Trends Cell Biol 2015; 25:730-748. [DOI: 10.1016/j.tcb.2015.10.004] [Citation(s) in RCA: 185] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 10/03/2015] [Accepted: 10/05/2015] [Indexed: 11/25/2022]
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Role for NUP62 depletion and PYK2 redistribution in dendritic retraction resulting from chronic stress. Proc Natl Acad Sci U S A 2014; 111:16130-5. [PMID: 25349423 DOI: 10.1073/pnas.1418896111] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Genetic evidence suggests cell-type-specific functions for certain nucleoporins, and gene expression profiling has revealed that nucleoporin p62 (NUP62) transcripts are decreased in the prefrontal cortex of major depressives. Chronic stress, which can precipitate depression, induces changes in the architecture and plasticity of apical dendrites that are particularly evident in the CA3 region of the hippocampus. Genetically targeted translating ribosome affinity purification revealed a selective reduction in translated Nup62 transcripts in CA3 of chronically stressed mice, and the Nup62 protein content of nuclei extracted from whole hippocampus was found to be decreased in chronically stressed rats. In cultured cells, phosphorylation of a FAK/proline-rich tyrosine kinase 2 (PYK2) consensus site in the alpha-helical domain of NUP62 (human Y422) is shown to be associated with shedding of NUP62 from the nuclear pore complex (NPC) and/or retention of NUP62 in the cytoplasm. Increased levels of phospho-Y425 Nup62 were observed in cytoplasmic fractions of hippocampi from chronically stressed rats, and immunofluorescence microscopy revealed redistribution of activated Pyk2 to the perinuclear region of stressed pyramidal neurons. Depletion of Nup62 from cultured embryonic day 18 rat hippocampal and cortical neurons resulted in simplification and retraction of dendritic arbors, without disruption of axon initial segment integrity. Thus, at least two types of mechanisms--one affecting expression and the other association with the NPC--could contribute to loss of NUP62 from CA3 pyramidal neurons during chronic stress. Their combined actions may account for the enhanced responsiveness of CA3 apical dendrites to chronic stress and may either be pathogenic or serve to protect CA3 neurons from permanent damage.
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Fichtman B, Harel A. Stress and aging at the nuclear gateway. Mech Ageing Dev 2014; 135:24-32. [PMID: 24447784 DOI: 10.1016/j.mad.2014.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 12/31/2013] [Accepted: 01/06/2014] [Indexed: 12/11/2022]
Abstract
The nuclear pore complex (NPC) is a massive molecular machine embedded in the nuclear envelope and controlling traffic into and out of the cell nucleus. Here, we describe some of the outstanding research questions concerning the NPC, its assembly and functions. We also discuss recent findings that link the NPC and its immediate surroundings to the process of cellular aging. Scaffold and barrier nucleoporins are two major types of protein building blocks that make up the NPC. Surprisingly, these two groups of nucleoporins differ dramatically in their turnover rates. Recent work identifies some of the scaffold nucleoporins as the most extremely long-lived proteins in rat brain. Some of the consequences of these findings and new open questions arising from them are discussed. We also consider the evidence for a perturbed permeability barrier in nuclei from old cells and the alteration of nuclear transport pathways under stress conditions. Finally, we describe the connection between premature aging syndromes and the nuclear lamina, a filamentous protein network which underlies the nuclear envelope.
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Affiliation(s)
- Boris Fichtman
- Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, 1311502, Israel
| | - Amnon Harel
- Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, 1311502, Israel.
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17
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Hashizume C, Moyori A, Kobayashi A, Yamakoshi N, Endo A, Wong RW. Nucleoporin Nup62 maintains centrosome homeostasis. Cell Cycle 2013; 12:3804-16. [PMID: 24107630 PMCID: PMC3905072 DOI: 10.4161/cc.26671] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Centrosomes are comprised of 2 orthogonally arranged centrioles surrounded by the pericentriolar material (PCM), which serves as the main microtubule organizing center of the animal cell. More importantly, centrosomes also control spindle polarity and orientation during mitosis. Recently, we and other investigators discovered that several nucleoporins play critical roles during cell division. Here, we show that nucleoporin Nup62 plays a novel role in centrosome integrity. Knockdown of Nup62 induced mitotic arrest in G2/M phases and mitotic cell death. Depletion of Nup62 using RNA interference results in defective centrosome segregation and centriole maturation during the G2 phase. Moreover, Nup62 depletion in human cells leads to the appearance of multinucleated cells and induces the formation of multipolar centrosomes, centriole synthesis defects, dramatic spindle orientation defects, and centrosome component rearrangements that impair cell bi-polarity. Our results also point to a potential role of Nup62 in targeting gamma-tubulin and SAS-6 to the centrioles.
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Affiliation(s)
- Chieko Hashizume
- Laboratory of Molecular and Cellular Biology; Department of Biology; Faculty of Natural Systems; Institute of Science and Engineering; Kanazawa University; Kakuma-machi, Kanazawa, Japan
| | - Akane Moyori
- Laboratory of Molecular and Cellular Biology; Department of Biology; Faculty of Natural Systems; Institute of Science and Engineering; Kanazawa University; Kakuma-machi, Kanazawa, Japan; Division of Natural System; Graduate School of Natural Science and Technology; Kanazawa University; Kakuma-machi, Kanazawa, Japan
| | - Akiko Kobayashi
- Laboratory of Molecular and Cellular Biology; Department of Biology; Faculty of Natural Systems; Institute of Science and Engineering; Kanazawa University; Kakuma-machi, Kanazawa, Japan
| | - Nana Yamakoshi
- Laboratory of Molecular and Cellular Biology; Department of Biology; Faculty of Natural Systems; Institute of Science and Engineering; Kanazawa University; Kakuma-machi, Kanazawa, Japan; Division of Natural System; Graduate School of Natural Science and Technology; Kanazawa University; Kakuma-machi, Kanazawa, Japan
| | - Aoi Endo
- Laboratory of Molecular and Cellular Biology; Department of Biology; Faculty of Natural Systems; Institute of Science and Engineering; Kanazawa University; Kakuma-machi, Kanazawa, Japan
| | - Richard W Wong
- Laboratory of Molecular and Cellular Biology; Department of Biology; Faculty of Natural Systems; Institute of Science and Engineering; Kanazawa University; Kakuma-machi, Kanazawa, Japan; Bio-AFM Frontier Research Center; Kanazawa University; Kakuma-machi, Kanazawa, Japan
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Yoshimura SH, Otsuka S, Kumeta M, Taga M, Takeyasu K. Intermolecular disulfide bonds between nucleoporins regulate karyopherin-dependent nuclear transport. J Cell Sci 2013; 126:3141-50. [PMID: 23641069 DOI: 10.1242/jcs.124172] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Disulfide (S-S) bonds play important roles in the regulation of protein function and cellular stress responses. In this study, we demonstrate that distinct sets of nucleoporins (Nups), components of the nuclear pore complex (NPC), form S-S bonds and regulate nuclear transport through the NPC. Kinetic analysis of importin β demonstrated that the permeability of the NPC was increased by dithiothreitol treatment and reduced by oxidative stress. The permeability of small proteins such as GFP was not affected by either oxidative stress or a reducing reagent. Immunoblot analysis revealed that the oxidative stress significantly induced S-S bond formation in Nups 358, 155, 153 and 62 but not 88 and 160. The direct involvement of cysteine residues in the formation of S-S bonds was confirmed by mutating conserved cysteine residues in Nup62, which abolished the formation of S-S bonds and enhanced the permeability of the NPC. Knocking down Nup62 reduced the stress-inducible S-S bonds of Nup155, suggesting that Nup62 and Nup155 are covalently coupled via S-S bonds. From these results, we propose that the inner channel of the NPC is somehow insulated from the cytoplasm and is more sensitive than the cytoplasm to the intracellular redox state.
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Affiliation(s)
- Shige H Yoshimura
- Graduate School of Biostudies, Kyoto University, Yoshida-konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
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Nuclear pore complex composition: a new regulator of tissue-specific and developmental functions. Nat Rev Mol Cell Biol 2013; 13:687-99. [PMID: 23090414 DOI: 10.1038/nrm3461] [Citation(s) in RCA: 251] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Nuclear pore complexes (NPCs) are multiprotein aqueous channels that penetrate the nuclear envelope connecting the nucleus and the cytoplasm. NPCs consist of multiple copies of roughly 30 different proteins known as nucleoporins (NUPs). Due to their essential role in controlling nucleocytoplasmic transport, NPCs have traditionally been considered as structures of ubiquitous composition. The overall structure of the NPC is indeed conserved in all cells, but new evidence suggests that the protein composition of NPCs varies among cell types and tissues. Moreover, mutations in various nucleoporins result in tissue-specific diseases. These findings point towards a heterogeneity in NPC composition and function. This unexpected heterogeneity suggests that cells use a combination of different nucleoporins to assemble NPCs with distinct properties and specialized functions.
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