1
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Scott KL, Halfmann CT, Hoefakker AD, Purkayastha P, Wang TC, Lele TP, Roux KJ. Nucleocytoplasmic transport rates are regulated by cellular processes that modulate GTP availability. J Cell Biol 2024; 223:e202308152. [PMID: 38683248 PMCID: PMC11059771 DOI: 10.1083/jcb.202308152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 03/08/2024] [Accepted: 04/01/2024] [Indexed: 05/01/2024] Open
Abstract
Nucleocytoplasmic transport (NCT), the facilitated diffusion of cargo molecules between the nucleus and cytoplasm through nuclear pore complexes (NPCs), enables numerous fundamental eukaryotic cellular processes. Ran GTPase uses cellular energy in the direct form of GTP to create a gradient across the nuclear envelope (NE) that drives the majority of NCT. We report here that changes in GTP availability resulting from altered cellular physiology modulate the rate of NCT, as monitored using synthetic and natural cargo, and the dynamics of Ran itself. Cell migration, cell spreading, and/or modulation of the cytoskeleton or its connection to the nucleus alter GTP availability and thus rates of NCT, regulating RNA export and protein synthesis. These findings support a model in which changes in cellular physiology that alter GTP availability can regulate the rate of NCT, impacting fundamental cellular processes that extensively utilize NCT.
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Affiliation(s)
- Kelsey L. Scott
- Enabling Technologies Group, Sanford Research, Sioux Falls, SD, USA
| | | | - Allison D. Hoefakker
- Enabling Technologies Group, Sanford Research, Sioux Falls, SD, USA
- Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, USA
| | - Purboja Purkayastha
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
| | - Ting Ching Wang
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
| | - Tanmay P. Lele
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
- Department of Translational Medical Sciences, Texas A&M University, Houston, TX, USA
| | - Kyle J. Roux
- Enabling Technologies Group, Sanford Research, Sioux Falls, SD, USA
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD, USA
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2
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Xiao R, Zhang L, Xin Z, Zhu J, Zhang Q, Zheng G, Chu S, Wu J, Zhang L, Wan Y, Chen X, Yuan W, Zhang Z, Zhu X, Fang X. Disruption of mitochondrial energy metabolism is a putative pathogenesis of Diamond-Blackfan anemia. iScience 2024; 27:109172. [PMID: 38414864 PMCID: PMC10897903 DOI: 10.1016/j.isci.2024.109172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 12/23/2023] [Accepted: 02/06/2024] [Indexed: 02/29/2024] Open
Abstract
Energy metabolism in the context of erythropoiesis and related diseases remains largely unexplored. Here, we developed a primary cell model by differentiating hematopoietic stem progenitor cells toward the erythroid lineage and suppressing the mitochondrial oxidative phosphorylation (OXPHOS) pathway. OXPHOS suppression led to differentiation failure of erythroid progenitors and defects in ribosome biogenesis. Ran GTPase-activating protein 1 (RanGAP1) was identified as a target of mitochondrial OXPHOS for ribosomal defects during erythropoiesis. Overexpression of RanGAP1 largely alleviated erythroid defects resulting from OXPHOS suppression. Coenzyme Q10, an activator of OXPHOS, largely rescued erythroid defects and increased RanGAP1 expression. Patients with Diamond-Blackfan anemia (DBA) exhibited OXPHOS suppression and a concomitant suppression of ribosome biogenesis. RNA-seq analysis implied that the substantial mutation (approximately 10%) in OXPHOS genes accounts for OXPHOS suppression in these patients. Conclusively, OXPHOS disruption and the associated disruptive mitochondrial energy metabolism are linked to the pathogenesis of DBA.
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Affiliation(s)
- Rudan Xiao
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Lijuan Zhang
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Zijuan Xin
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Junwei Zhu
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
| | - Qian Zhang
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
| | - Guangmin Zheng
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Siyun Chu
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
| | - Jing Wu
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing 101408, P.R. China
| | - Lu Zhang
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Yang Wan
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Xiaojuan Chen
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Weiping Yuan
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Zhaojun Zhang
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing 101408, P.R. China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, P.R. China
- Beijing Key Laboratory of Genome and Precision Medicine Technologies, Beijing 100101, P.R. China
| | - Xiaofan Zhu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Xiangdong Fang
- Beijing Institute of Genomics, Chinese Academy of Sciences & China National Center for Bioinformation, Beijing 100101, P.R. China
- University of Chinese Academy of Sciences, Beijing 100049, P.R. China
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing 101408, P.R. China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, P.R. China
- Beijing Key Laboratory of Genome and Precision Medicine Technologies, Beijing 100101, P.R. China
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3
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Cosgrove BD, Bounds LR, Taylor CK, Su AL, Rizzo AJ, Barrera A, Crawford GE, Hoffman BD, Gersbach CA. Mechanosensitive genomic enhancers potentiate the cellular response to matrix stiffness. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.10.574997. [PMID: 38260455 PMCID: PMC10802421 DOI: 10.1101/2024.01.10.574997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Epigenetic control of cellular transcription and phenotype is influenced by changes in the cellular microenvironment, yet how mechanical cues from these microenvironments precisely influence epigenetic state to regulate transcription remains largely unmapped. Here, we combine genome-wide epigenome profiling, epigenome editing, and phenotypic and single-cell RNA-seq CRISPR screening to identify a new class of genomic enhancers that responds to the mechanical microenvironment. These 'mechanoenhancers' could be active on either soft or stiff extracellular matrix contexts, and regulated transcription to influence critical cell functions including apoptosis, mechanotransduction, proliferation, and migration. Epigenetic editing of mechanoenhancers on rigid materials tuned gene expression to levels observed on softer materials, thereby reprogramming the cellular response to the mechanical microenvironment. These editing approaches may enable the precise alteration of mechanically-driven disease states.
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Affiliation(s)
- Brian D. Cosgrove
- Department of Biomedical Engineering, Duke University; Durham, NC 27708, USA
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
| | - Lexi R. Bounds
- Department of Biomedical Engineering, Duke University; Durham, NC 27708, USA
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
| | - Carson Key Taylor
- Department of Biomedical Engineering, Duke University; Durham, NC 27708, USA
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
| | - Alan L. Su
- Department of Biomedical Engineering, Duke University; Durham, NC 27708, USA
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
| | - Anthony J. Rizzo
- Department of Biomedical Engineering, Duke University; Durham, NC 27708, USA
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
| | - Alejandro Barrera
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
- Department of Biostatistics and Bioinformatics, Duke University; Durham, NC 27708, USA
| | - Gregory E. Crawford
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
- Department of Pediatrics, Duke University Medical Center; Durham, NC 27708, USA
| | - Brenton D. Hoffman
- Department of Biomedical Engineering, Duke University; Durham, NC 27708, USA
- Department of Cell Biology, Duke University; Durham, NC 27708, USA
| | - Charles A. Gersbach
- Department of Biomedical Engineering, Duke University; Durham, NC 27708, USA
- Center for Advanced Genomic Technologies, Duke University; Durham, NC 27708, USA
- Department of Cell Biology, Duke University; Durham, NC 27708, USA
- Department of Surgery, Duke University Medical Center; Durham, NC 27708, USA
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4
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Goswami R, Gupta A, Bednova O, Coulombe G, Patel D, Rotello VM, Leyton JV. Nuclear localization signal-tagged systems: relevant nuclear import principles in the context of current therapeutic design. Chem Soc Rev 2024; 53:204-226. [PMID: 38031452 PMCID: PMC10798298 DOI: 10.1039/d1cs00269d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Nuclear targeting of therapeutics provides a strategy for enhancing efficacy of molecules active in the nucleus and minimizing off-target effects. 'Active' nuclear-directed transport and efficient translocations across nuclear pore complexes provide the most effective means of maximizing nuclear localization. Nuclear-targeting systems based on nuclear localization signal (NLS) motifs have progressed significantly since the beginning of the current millennium. Here, we offer a roadmap for understanding the basic mechanisms of nuclear import in the context of actionable therapeutic design for developing NLS-therapeutics with improved treatment efficacy.
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Affiliation(s)
- Ritabrita Goswami
- Department of Chemistry, University of Massachusetts, Massachusetts, USA.
| | - Aarohi Gupta
- Department of Chemistry, University of Massachusetts, Massachusetts, USA.
| | - Olga Bednova
- Département de médecine nucléaire et radiobiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Québec, Canada
| | - Gaël Coulombe
- Service des stages et du développement professionnel, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Dipika Patel
- Service des stages et du développement professionnel, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Vincent M Rotello
- Department of Chemistry, University of Massachusetts, Massachusetts, USA.
| | - Jeffrey V Leyton
- École des sciences pharmaceutiques, Université d'Ottawa, Ottawa, Ontario, Canada.
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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5
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Scott KL, Halfmann CT, Hoefakker AD, Purkayastha P, Wang TC, Lele TP, Roux KJ. Nucleocytoplasmic transport rates are regulated by cellular processes that modulate GTP availability. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.29.573651. [PMID: 38234722 PMCID: PMC10793428 DOI: 10.1101/2023.12.29.573651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Nucleocytoplasmic transport (NCT), the facilitated diffusion of cargo molecules between the nucleus and cytoplasm through nuclear pore complexes (NPCs), enables numerous fundamental eukaryotic cellular processes. Ran GTPase uses cellular energy in the direct form of GTP to create a gradient across the nuclear envelope (NE) that drives the majority of NCT. We report here that changes in GTP availability resulting from altered cellular physiology modulate the rate of NCT, as monitored using synthetic and natural cargo, and the dynamics of Ran itself. Cell migration, cell spreading and/or modulation of the cytoskeleton or its connection to the nucleus alter GTP availability and thus rates of NCT, regulating RNA export and protein synthesis. These findings support a model in which changes in cellular physiology that alter GTP availability can regulate the rate of NCT, impacting fundamental cellular processes that extensively utilize NCT.
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Affiliation(s)
- Kelsey L. Scott
- Enabling Technologies Group, Sanford Research, Sioux Falls SD
| | | | - Allison D. Hoefakker
- Enabling Technologies Group, Sanford Research, Sioux Falls SD
- Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD
| | - Purboja Purkayastha
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas
| | - Ting Ching Wang
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas
| | - Tanmay P. Lele
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas
- Department of Translational Medical Sciences, Texas A&M University, Houston, Texas
| | - Kyle J. Roux
- Enabling Technologies Group, Sanford Research, Sioux Falls SD
- Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD
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6
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Yang Y, Guo L, Chen L, Gong B, Jia D, Sun Q. Nuclear transport proteins: structure, function, and disease relevance. Signal Transduct Target Ther 2023; 8:425. [PMID: 37945593 PMCID: PMC10636164 DOI: 10.1038/s41392-023-01649-4] [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: 04/09/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 11/12/2023] Open
Abstract
Proper subcellular localization is crucial for the functioning of biomacromolecules, including proteins and RNAs. Nuclear transport is a fundamental cellular process that regulates the localization of many macromolecules within the nuclear or cytoplasmic compartments. In humans, approximately 60 proteins are involved in nuclear transport, including nucleoporins that form membrane-embedded nuclear pore complexes, karyopherins that transport cargoes through these complexes, and Ran system proteins that ensure directed and rapid transport. Many of these nuclear transport proteins play additional and essential roles in mitosis, biomolecular condensation, and gene transcription. Dysregulation of nuclear transport is linked to major human diseases such as cancer, neurodegenerative diseases, and viral infections. Selinexor (KPT-330), an inhibitor targeting the nuclear export factor XPO1 (also known as CRM1), was approved in 2019 to treat two types of blood cancers, and dozens of clinical trials of are ongoing. This review summarizes approximately three decades of research data in this field but focuses on the structure and function of individual nuclear transport proteins from recent studies, providing a cutting-edge and holistic view on the role of nuclear transport proteins in health and disease. In-depth knowledge of this rapidly evolving field has the potential to bring new insights into fundamental biology, pathogenic mechanisms, and therapeutic approaches.
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Affiliation(s)
- Yang Yang
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lu Guo
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lin Chen
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Bo Gong
- The Key Laboratory for Human Disease Gene Study of Sichuan Province and Department of Laboratory Medicine, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China
| | - Da Jia
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Pediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, China.
| | - Qingxiang Sun
- Department of Pulmonary and Critical Care Medicine, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China.
- Department of Pathology, State Key Laboratory of Biotherapy and Cancer Centre, West China Hospital, Sichuan University, and Collaborative Innovation Centre of Biotherapy, Chengdu, China.
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7
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Garg R, Endzhievskaya S, Williamson M. B-type Plexins promote the GTPase activity of Ran to affect androgen receptor nuclear translocation in prostate cancer. Cancer Gene Ther 2023; 30:1513-1523. [PMID: 37563360 PMCID: PMC10645588 DOI: 10.1038/s41417-023-00655-6] [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: 02/16/2023] [Revised: 07/10/2023] [Accepted: 08/01/2023] [Indexed: 08/12/2023]
Abstract
Resistance to anti-androgen therapy for metastatic prostate cancer is a major clinical problem. Sema3C promotes resistance to androgen withdrawal via its receptor, PlexinB1. Activation of PlexinB1 promotes the ligand-independent nuclear translocation of the androgen receptor (AR), which may contribute to resistance to androgen deprivation therapy. However, the mechanism by which PlexinB1 promotes nuclear translocation is unclear. We show here that PlexinB1 and B2 regulate nuclear import by acting as GTPase activating proteins (GAPs) for the small RasGTPase Ran, a key regulator of nuclear trafficking. Purified PlexinB1/B2 protein catalyses the hydrolysis of RanGTP, and mutations in the GAP domain of PlexinB1 inhibit this activity. Activation of PlexinB1/B2 with Sema4D decreases the levels of RanGTP, while PlexinB1 or B2 depletion increases the levels of activated Ran in the cell. Ran directly associates with B-type plexins in a GTP-dependent manner. Sema4D is internalised by endocytosis, and PlexinB1 and Ran display overlapping patterns of expression. Furthermore, Sema4D/PlexinB1-induced AR nuclear translocation is dependent on the GAP domain of PlexinB1 and is blocked by the expression of non-functional Ran mutants. Depletion of PlexinB1 decreases the nuclear/cytoplasmic ratio of Ran, indicative of a higher RanGTP/GDP ratio. Plexins may promote the growth of androgen-independent prostate cancer through their activity as RanGAPs.
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Affiliation(s)
- Ritu Garg
- School of Cancer and Pharmaceutical Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Sofia Endzhievskaya
- Randall Division of Cell and Molecular Biophysics, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Magali Williamson
- School of Cancer and Pharmaceutical Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK.
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8
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Cristi AC, Rapuri S, Coyne AN. Nuclear pore complex and nucleocytoplasmic transport disruption in neurodegeneration. FEBS Lett 2023; 597:2546-2566. [PMID: 37657945 PMCID: PMC10612469 DOI: 10.1002/1873-3468.14729] [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: 06/25/2023] [Revised: 07/29/2023] [Accepted: 08/24/2023] [Indexed: 09/03/2023]
Abstract
Nuclear pore complexes (NPCs) play a critical role in maintaining the equilibrium between the nucleus and cytoplasm, enabling bidirectional transport across the nuclear envelope, and are essential for proper nuclear organization and gene regulation. Perturbations in the regulatory mechanisms governing NPCs and nuclear envelope homeostasis have been implicated in the pathogenesis of several neurodegenerative diseases. The ESCRT-III pathway emerges as a critical player in the surveillance and preservation of well-assembled, functional NPCs, as well as nuclear envelope sealing. Recent studies have provided insights into the involvement of nuclear ESCRT-III in the selective reduction of specific nucleoporins associated with neurodegenerative pathologies. Thus, maintaining quality control of the nuclear envelope and NPCs represents a pivotal element in the pathological cascade leading to neurodegenerative diseases. This review describes the constituents of the nuclear-cytoplasmic transport machinery, encompassing the nuclear envelope, NPC, and ESCRT proteins, and how their structural and functional alterations contribute to the development of neurodegenerative diseases.
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Affiliation(s)
- América Chandía Cristi
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
| | - Sampath Rapuri
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
| | - Alyssa N Coyne
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
- Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore MD 21205, USA
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9
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Yeo EJ, Shin MJ, Youn GS, Park JH, Yeo HJ, Kwon HJ, Lee LR, Kim NY, Kwon SY, Kim SM, Lee J, Lee KW, Lee CH, Cho YJ, Kwon OS, Kim DW, Jung HY, Eum WS, Choi SY. Tat-RAN attenuates brain ischemic injury in hippocampal HT-22 cells and ischemia animal model. Neurochem Int 2023; 167:105538. [PMID: 37207854 DOI: 10.1016/j.neuint.2023.105538] [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: 02/16/2023] [Revised: 04/30/2023] [Accepted: 05/07/2023] [Indexed: 05/21/2023]
Abstract
Oxidative stress plays a key role in the pathogenesis of neuronal injury, including ischemia. Ras-related nuclear protein (RAN), a member of the Ras superfamily, involves in a variety of biological roles, such as cell division, proliferation, and signal transduction. Although RAN reveals antioxidant effect, its precise neuroprotective mechanisms are still unclear. Therefore, we investigated the effects of RAN on HT-22 cell which were exposed to H2O2-induced oxidative stress and ischemia animal model by using the cell permeable Tat-RAN fusion protein. We showed that Tat-RAN transduced into HT-22 cells, and markedly inhibited cell death, DNA fragmentation, and reactive oxygen species (ROS) generation under oxidative stress. This fusion protein also controlled cellular signaling pathways, including mitogen-activated protein kinases (MAPKs), NF-κB, and apoptosis (Caspase-3, p53, Bax and Bcl-2). In the cerebral forebrain ischemia animal model, Tat-RAN significantly inhibited both neuronal cell death, and astrocyte and microglia activation. These results indicate that RAN significantly protects against hippocampal neuronal cell death, suggesting Tat-RAN will help to develop the therapies for neuronal brain diseases including ischemic injury.
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Affiliation(s)
- Eun Ji Yeo
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Min Jea Shin
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Gi Soo Youn
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Jung Hwan Park
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Hyeon Ji Yeo
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Hyun Jung Kwon
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Lee Re Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Na Yeon Kim
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Su Yeon Kwon
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Su Min Kim
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Jaehak Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Keun Wook Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Chan Hee Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Yong-Jun Cho
- Department of Neurosurgery, Hallym University Medical Center, Chuncheon, 24253, South Korea
| | - Oh-Shin Kwon
- School of Life Sciences, College of Natural Sciences Kyungpook National University, Taegu, 41566, South Korea
| | - Dae Won Kim
- Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung-Wonju National University, Gangneung, 25457, South Korea
| | - Hyo Young Jung
- Department of Veterinary Medicine & Institute of Veterinary Science, Chungnam National University, Daejeon, 34134, South Korea
| | - Won Sik Eum
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea.
| | - Soo Young Choi
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea.
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10
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Shrestha S, Ems-McClung SC, Hazelbaker MA, Yount AL, Shaw SL, Walczak CE. Importin α/β promote Kif18B microtubule association and enhance microtubule destabilization activity. Mol Biol Cell 2023; 34:ar30. [PMID: 36790918 PMCID: PMC10092650 DOI: 10.1091/mbc.e22-03-0113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Tight regulation of microtubule (MT) dynamics is necessary for proper spindle assembly and chromosome segregation. The MT destabilizing Kinesin-8, Kif18B, controls astral MT dynamics and spindle positioning. Kif18B interacts with importin α/β as well as with the plus-tip tracking protein EB1, but how these associations modulate Kif18B is not known. We mapped the key binding sites on Kif18B, made residue-specific mutations, and assessed their impact on Kif18B function. Blocking EB1 interaction disrupted Kif18B MT plus-end accumulation and inhibited its ability to control MT length on monopolar spindles in cells. Blocking importin α/β interaction disrupted Kif18B localization without affecting aster size. In vitro, importin α/β increased Kif18B MT association by increasing the on-rate and decreasing the off-rate from MTs, which stimulated MT destabilization. In contrast, EB1 promoted MT destabilization without increasing lattice binding in vitro, which suggests that EB1 and importin α/β have distinct roles in the regulation of Kif18B-mediated MT destabilization. We propose that importin α/β spatially modulate Kif18B association with MTs to facilitate its MT destabilization activity. Our results suggest that Ran regulation is important not only to control molecular motor function near chromatin but also to provide a spatial control mechanism to modulate MT binding of nuclear localization signal-containing spindle assembly factors.
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Affiliation(s)
- Sanjay Shrestha
- Medical Sciences, Indiana School of Medicine-Bloomington, Bloomington, IN 47405
| | | | - Mark A Hazelbaker
- Medical Sciences, Indiana School of Medicine-Bloomington, Bloomington, IN 47405
| | - Amber L Yount
- Medical Sciences, Indiana School of Medicine-Bloomington, Bloomington, IN 47405
| | - Sidney L Shaw
- Department of Biology, Indiana University, Bloomington, IN 47405
| | - Claire E Walczak
- Medical Sciences, Indiana School of Medicine-Bloomington, Bloomington, IN 47405
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11
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Lin X, Pang Q, Hu J, Sun J, Dai S, Yu Y, Xu J. SUMOylation mediates the disassembly of the Smad4 nuclear export complex via RanGAP1 in KELOIDS. J Cell Mol Med 2023; 27:1045-1055. [PMID: 36916534 PMCID: PMC10098277 DOI: 10.1111/jcmm.17216] [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: 09/23/2021] [Revised: 12/14/2021] [Accepted: 01/18/2022] [Indexed: 03/16/2023] Open
Abstract
Sentrin/small ubiquitin-like modifier (SUMO) has emerged as a powerful mediator regulating biological processes and participating in pathophysiological processes that cause human diseases, such as cancer, myocardial fibrosis and neurological disorders. Sumoylation has been shown to play a positive regulatory role in keloids. However, the sumoylation mechanism in keloids remains understudied. We proposed that sumoylation regulates keloids via a complex. RanGAP1 acted as a synergistic, functional partner of SUMOs in keloids. Nuclear accumulation of Smad4, a TGF-β/Smad pathway member, was associated with RanGAP1 after SUMO1 inhibition. RanGAP1*SUMO1 mediated the nuclear accumulation of Smad4 due to its impact on nuclear export and reduction in the dissociation of Smad4 and CRM1. We clarified a novel mechanism of positive regulation of sumoylation in keloids and demonstrated the function of sumoylation in Smad4 nuclear export. The NPC-associated RanGAP1*SUMO1 complex functions as a disassembly machine for the export receptor CRM1 and Smad4. Our research provides new perspectives for the mechanisms of keloids and nucleocytoplasmic transport.
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Affiliation(s)
- Xiaohu Lin
- Department of Plastic and Reconstructive Surgery, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
| | - Qianqian Pang
- Ningbo Hwamei Hospital, University of Chinese Academy of Sciences, Ningbo, Zhejiang, China
| | - Jie Hu
- Department of Plastic Surgery, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jiaqi Sun
- Department of Plastic Surgery, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Siya Dai
- Department of Plastic Surgery, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yijia Yu
- Department of Plastic Surgery, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jinghong Xu
- Department of Plastic Surgery, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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12
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Jibiki K, Kodama TS, Yasuhara N. Importin alpha family NAAT/IBB domain: Functions of a pleiotropic long chameleon sequence. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2023; 134:175-209. [PMID: 36858734 DOI: 10.1016/bs.apcsb.2022.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Nuclear transport is essential for eukaryotic cell survival and regulates the movement of functional molecules in and out of the nucleus via the nuclear pore. Transport is facilitated by protein-protein interactions between cargo and transport receptors, which contribute to the expression and regulation of downstream genetic information. This chapter focuses on the molecular basis of the multifunctional nature of the importin α family, the representative transport receptors that bring proteins into the nucleus. Importin α performs multiple functions during the nuclear transport cycle through interactions with multiple molecules by a single domain called the IBB domain. This domain is a long chameleon sequence, which can change its conformation and binding mode depending on the interaction partners. By considering the evolutionarily conserved biochemical/physicochemical propensities of the amino acids constituting the functional complex interfaces, together with their structural properties, the mechanisms of switching between multiple complexes formed via IBB and the regulation of downstream functions are examined in detail. The mechanism of regulation by IBB indicates that the time has come for a paradigm shift in the way we view the molecular mechanisms by which proteins regulate downstream functions through their interactions with other molecules.
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Affiliation(s)
- Kazuya Jibiki
- Graduate School of Integrated Basic Sciences, Nihon University, Setagaya-ku, Tokyo, Japan
| | - Takashi S Kodama
- Laboratory of Molecular Biophysics, Institute for Protein Research, Osaka University, Osaka, Japan.
| | - Noriko Yasuhara
- Graduate School of Integrated Basic Sciences, Nihon University, Setagaya-ku, Tokyo, Japan.
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13
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Loss of RanGAP1 drives chromosome instability and rapid tumorigenesis of osteosarcoma. Dev Cell 2023; 58:192-210.e11. [PMID: 36696903 DOI: 10.1016/j.devcel.2022.12.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 09/27/2022] [Accepted: 12/29/2022] [Indexed: 01/26/2023]
Abstract
Chromothripsis is a catastrophic event of chromosomal instability that involves intensive fragmentation and rearrangements within localized chromosomal regions. However, its cause remains unclear. Here, we show that reduction and inactivation of Ran GTPase-activating protein 1 (RanGAP1) commonly occur in human osteosarcoma, which is associated with a high rate of chromothripsis. In rapidly expanding mouse osteoprogenitors, RanGAP1 deficiency causes chromothripsis in chr1q, instant inactivation of Rb1 and degradation of p53, consequent failure in DNA damage repair, and ultrafast osteosarcoma tumorigenesis. During mitosis, RanGAP1 anchors to the kinetochore, where it recruits PP1-γ to counteract the activity of the spindle-assembly checkpoint (SAC) and prevents TOP2A degradation, thus safeguarding chromatid decatenation. Loss of RanGAP1 causes SAC hyperactivation and chromatid decatenation failure. These findings demonstrate that RanGAP1 maintains mitotic chromosome integrity and that RanGAP1 loss drives tumorigenesis through its direct effects on SAC and decatenation and secondary effects on DNA damage surveillance.
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14
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Differential nuclear import sets the timing of protein access to the embryonic genome. Nat Commun 2022; 13:5887. [PMID: 36202846 PMCID: PMC9537182 DOI: 10.1038/s41467-022-33429-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 09/16/2022] [Indexed: 02/02/2023] Open
Abstract
The development of a fertilized egg to an embryo requires the proper temporal control of gene expression. During cell differentiation, timing is often controlled via cascades of transcription factors (TFs). However, in early development, transcription is often inactive, and many TF levels stay constant, suggesting that alternative mechanisms govern the observed rapid and ordered onset of gene expression. Here, we find that in early embryonic development access of maternally deposited nuclear proteins to the genome is temporally ordered via importin affinities, thereby timing the expression of downstream targets. We quantify changes in the nuclear proteome during early development and find that nuclear proteins, such as TFs and RNA polymerases, enter the nucleus sequentially. Moreover, we find that the timing of nuclear proteins' access to the genome corresponds to the timing of downstream gene activation. We show that the affinity of proteins to importin is a major determinant in the timing of protein entry into embryonic nuclei. Thus, we propose a mechanism by which embryos encode the timing of gene expression in early development via biochemical affinities. This process could be critical for embryos to organize themselves before deploying the regulatory cascades that control cell identities.
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15
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Lu S, Hu J, Arogundade OA, Goginashvili A, Vazquez-Sanchez S, Diedrich JK, Gu J, Blum J, Oung S, Ye Q, Yu H, Ravits J, Liu C, Yates JR, Cleveland DW. Heat-shock chaperone HSPB1 regulates cytoplasmic TDP-43 phase separation and liquid-to-gel transition. Nat Cell Biol 2022; 24:1378-1393. [PMID: 36075972 PMCID: PMC9872726 DOI: 10.1038/s41556-022-00988-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 07/28/2022] [Indexed: 01/27/2023]
Abstract
While acetylated, RNA-binding-deficient TDP-43 reversibly phase separates within nuclei into complex droplets (anisosomes) comprised of TDP-43-containing liquid outer shells and liquid centres of HSP70-family chaperones, cytoplasmic aggregates of TDP-43 are hallmarks of multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Here we show that transient oxidative stress, proteasome inhibition or inhibition of the ATP-dependent chaperone activity of HSP70 provokes reversible cytoplasmic TDP-43 de-mixing and transition from liquid to gel/solid, independently of RNA binding or stress granules. Isotope labelling mass spectrometry was used to identify that phase-separated cytoplasmic TDP-43 is bound by the small heat-shock protein HSPB1. Binding is direct, mediated through TDP-43's RNA binding and low-complexity domains. HSPB1 partitions into TDP-43 droplets, inhibits TDP-43 assembly into fibrils, and is essential for disassembly of stress-induced TDP-43 droplets. A decrease in HSPB1 promotes cytoplasmic TDP-43 de-mixing and mislocalization. HSPB1 depletion was identified in spinal motor neurons of patients with ALS containing aggregated TDP-43. These findings identify HSPB1 to be a regulator of cytoplasmic TDP-43 phase separation and aggregation.
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Affiliation(s)
- Shan Lu
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | - Jiaojiao Hu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | | | - Alexander Goginashvili
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | - Sonia Vazquez-Sanchez
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | | | - Jinge Gu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jacob Blum
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Spencer Oung
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
- Ludwig Institute for Cancer Research, San Diego, CA, USA
| | - Qiaozhen Ye
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA
| | - Haiyang Yu
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - John Ravits
- Department of Neurosciences, University of California, San Diego, CA, USA
| | - Cong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - John R Yates
- The Scripps Research Institute, La Jolla, CA, USA
| | - Don W Cleveland
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA, USA.
- Ludwig Institute for Cancer Research, San Diego, CA, USA.
- Department of Neurosciences, University of California, San Diego, CA, USA.
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16
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Chavan S, Khuperkar D, Lonare A, Panigrahi S, Bellare J, Rapole S, Seshadri V, Joseph J. RanGTPase links nucleo-cytoplasmic transport to the recruitment of cargoes into small extracellular vesicles. Cell Mol Life Sci 2022; 79:392. [PMID: 35779171 PMCID: PMC11071952 DOI: 10.1007/s00018-022-04422-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/09/2022] [Accepted: 06/13/2022] [Indexed: 11/24/2022]
Abstract
Small extracellular vesicle (sEV)-mediated intercellular communication regulates multiple aspects of growth and development in multicellular organisms. However, the mechanism underlying cargo recruitment into sEVs is currently unclear. We show that the key nucleo-cytoplasmic transport (NCT) protein-RanGTPase, in its GTP-bound form (RanGTP), is enriched in sEVs secreted by mammalian cells. This recruitment of RanGTP into sEVs depends on the export receptor CRM1 (also called XPO1). The recruitment of GAPDH, a candidate cargo protein, into sEVs is regulated by the RanGTP-CRM1axis in a nuclear export signal (NES)-dependent manner. Perturbation of NCT through overexpression or depletion of nuclear transport components affected the recruitment of Ran, CRM1 and GAPDH into sEVs. Our studies, thus, suggest a link between NCT, particularly the Ran-CRM1 axis, and recruitment of NES-containing cargoes into the sEVs. Collectively, these findings implicate RanGTPase as a link between NCT and sEV mediated intercellular communication.
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Affiliation(s)
- Sakalya Chavan
- National Centre for Cell Science, S.P. Pune University Campus, Ganeshkhind, Pune, 411007, India
| | - Deepak Khuperkar
- National Centre for Cell Science, S.P. Pune University Campus, Ganeshkhind, Pune, 411007, India
- UK Dementia Research Institute at King's College London, London and University of Cambridge, Cambridge, UK
| | - Akshay Lonare
- National Centre for Cell Science, S.P. Pune University Campus, Ganeshkhind, Pune, 411007, India
| | - Swagatika Panigrahi
- National Centre for Cell Science, S.P. Pune University Campus, Ganeshkhind, Pune, 411007, India
| | - Jayesh Bellare
- Department of Chemical Engineering and Wadhwani Research Centre for Bioengineering, IIT Bombay, Mumbai, 400079, India
| | - Srikanth Rapole
- National Centre for Cell Science, S.P. Pune University Campus, Ganeshkhind, Pune, 411007, India
| | - Vasudevan Seshadri
- National Centre for Cell Science, S.P. Pune University Campus, Ganeshkhind, Pune, 411007, India
| | - Jomon Joseph
- National Centre for Cell Science, S.P. Pune University Campus, Ganeshkhind, Pune, 411007, India.
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17
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Baud A, Derbis M, Tutak K, Sobczak K. Partners in crime: Proteins implicated in
RNA
repeat expansion diseases. WIRES RNA 2022; 13:e1709. [PMID: 35229468 PMCID: PMC9539487 DOI: 10.1002/wrna.1709] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 11/06/2022]
Affiliation(s)
- Anna Baud
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Magdalena Derbis
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Katarzyna Tutak
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
| | - Krzysztof Sobczak
- Department of Gene Expression Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University Poznan Poland
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18
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Pham G, Shin DM, Kim Y, Kim SH. Ran-GTP/-GDP-dependent nuclear accumulation of NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 and TGACG-BINDING FACTOR2 controls salicylic acid-induced leaf senescence. PLANT PHYSIOLOGY 2022; 189:1774-1793. [PMID: 35417014 PMCID: PMC9237681 DOI: 10.1093/plphys/kiac164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 02/08/2022] [Indexed: 05/11/2023]
Abstract
Leaf senescence is the final stage of leaf development and can be triggered by various external factors, such as hormones and light deprivation. In this study, we demonstrate that the overexpression of the GTP-bound form of Arabidopsis (Arabidopsis thaliana) Ran1 (a Ras-related nuclear small G-protein, AtRan1) efficiently promotes age-dependent and dark-triggered leaf senescence, while Ran-GDP has the opposite effect. Transcriptome analysis comparing AtRan1-GDP- and AtRan1-GTP-overexpressing transgenic plants (Ran1T27Nox and Ran1G22Vox, respectively) revealed that differentially expressed genes (DEGs) related to the senescence-promoting hormones salicylic acid (SA), jasmonic acid, abscisic acid, and ethylene (ET) were significantly upregulated in dark-triggered senescing leaves of Ran1G22Vox, indicating that these hormones are actively involved in Ran-GTP/-GDP-dependent, dark-triggered leaf senescence. Bioinformatic analysis of the promoter regions of DEGs identified diverse consensus motifs, including the bZIP motif, a common binding site for TGACG-BINDING FACTOR (TGA) transcription factors. Interestingly, TGA2 and its interactor, NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 (NPR1), which are two positive transcriptional regulators of SA signaling, differed in their extent of accumulation in the nucleus versus cytoplasm of Ran1T27Nox and Ran1G22Vox plants. Moreover, SA-induced, Ran-GTP-/-GDP-dependent functions of NPR1 included genome-wide global transcriptional reprogramming of genes involved in cell death, aging, and chloroplast organization. Furthermore, the expression of AtRan1-GTP in SA signaling-defective npr1 and SA biosynthesis-deficient SA-induction deficient2 genetic backgrounds abolished the effects of AtRan1-GTP, thus retarding age-promoted leaf senescence. However, ET-induced leaf senescence was not mediated by Ran machinery-dependent nuclear shuttling of ETHYLENE-INSENSITIVE3 and ETHYLENE-INSENSITIVE3-LIKE1 proteins. We conclude that Ran-GTP/-GDP-dependent nuclear accumulation of NPR1 and TGA2 represents another regulatory node for SA-induced leaf senescence.
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Affiliation(s)
| | | | - Yoon Kim
- Division of Biological Science and Technology, Yonsei University, Yonseidae 1 Gil, Wonju-Si 220-710, South Korea
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19
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Luo N, Fu M, Zhang Y, Li X, Zhu W, Yang F, Chen Z, Mei Q, Peng X, Shen L, Zhang Y, Li Q, Hu G. Prognostic Role of M6A-Associated Immune Genes and Cluster-Related Tumor Microenvironment Analysis: A Multi-Omics Practice in Stomach Adenocarcinoma. Front Cell Dev Biol 2022; 10:935135. [PMID: 35859893 PMCID: PMC9291731 DOI: 10.3389/fcell.2022.935135] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 06/03/2022] [Indexed: 12/24/2022] Open
Abstract
N6-methylandrostenedione (m6A) methylation plays a very important role in the development of malignant tumors. The immune system is the key point in the progression of tumors, particularly in terms of tumor treatment and drug resistance. Tumor immunotherapy has now become a hot spot and a new approach for tumor treatment. However, as far as the stomach adenocarcinoma (STAD) is concerned, the in-depth research is still a gap in the m6A-associated immune markers. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases is extremely important for our research, where we obtained gene mutation, gene expression data and relevant clinical information of STAD patients. Firstly, the samples from GEO were used as external validation groups, while the TCGA samples were divided into a training group and an internal validation group randomly. Using the way of Single factor COX-LASSO- and multi-factor Cox to construct the prognostic model. Then, all samples were subjected to cluster analysis to generate high and low expression groups of immune gene. Meanwhile, we also collected the correlation between these types and tumor microenvironment. On this basis, a web version of the dynamic nomogram APP was developed. In addition, we performed microenvironmental correlation, copy number variation and mutation analyses for model genes. The prognostic model for STAD developed here demonstrated a very strong predictive ability. The results of cluster analysis manifested that the immune gene low expression group had lower survival rate and higher degree of immune infiltration. Therefore, the immune gene low expression group was associated with lower survival rates and a higher degree of immune infiltration. Gene set enrichment analysis suggested that the potential mechanism might be related to the activation of immunosuppressive functions and multiple signaling pathways. Correspondingly, the web version of the dynamic nomogram APP produced by the DynNom package has successfully achieved rapid and accurate calculation of patient survival rates. Finally, the multi-omics analysis of model genes further enriched the research content. Interference of RAB19 was confirmed to facilitate migration of STAD cells in vitro, while its overexpression inhibited these features. The prognostic model for STAD constructed in this study is accurate and efficient based on multi-omics analysis and experimental validation. Additionally, the results of the correlation analysis between the tumor microenvironment and m6Ascore are the basics of further exploration of the pathophysiological mechanism in STAD.
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Affiliation(s)
- Na Luo
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Min Fu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yiling Zhang
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoyu Li
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wenjun Zhu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Feng Yang
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ziqi Chen
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi Mei
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaohong Peng
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lulu Shen
- Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuanyuan Zhang
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Yuanyuan Zhang, ; Qianxia Li, ; Guangyuan Hu,
| | - Qianxia Li
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Yuanyuan Zhang, ; Qianxia Li, ; Guangyuan Hu,
| | - Guangyuan Hu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- *Correspondence: Yuanyuan Zhang, ; Qianxia Li, ; Guangyuan Hu,
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20
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Yunes SA, Willoughby JLS, Kwan JH, Biagi JM, Pokharel N, Chin HG, York EA, Su KC, George K, Shah JV, Emili A, Schaus SE, Hansen U. Factor quinolinone inhibitors disrupt spindles and multiple LSF (TFCP2)-protein interactions in mitosis, including with microtubule-associated proteins. PLoS One 2022; 17:e0268857. [PMID: 35704642 PMCID: PMC9200292 DOI: 10.1371/journal.pone.0268857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 05/09/2022] [Indexed: 11/19/2022] Open
Abstract
Factor quinolinone inhibitors (FQIs), a first-in-class set of small molecule inhibitors targeted to the transcription factor LSF (TFCP2), exhibit promising cancer chemotherapeutic properties. FQI1, the initial lead compound identified, unexpectedly induced a concentration-dependent delay in mitotic progression. Here, we show that FQI1 can rapidly and reversibly lead to mitotic arrest, even when added directly to mitotic cells, implying that FQI1-mediated mitotic defects are not transcriptionally based. Furthermore, treatment with FQIs resulted in a striking, concentration-dependent diminishment of spindle microtubules, accompanied by a concentration-dependent increase in multi-aster formation. Aberrant γ-tubulin localization was also observed. These phenotypes suggest that perturbation of spindle microtubules is the primary event leading to the mitotic delays upon FQI1 treatment. Previously, FQIs were shown to specifically inhibit not only LSF DNA-binding activity, which requires LSF oligomerization to tetramers, but also other specific LSF-protein interactions. Other transcription factors participate in mitosis through non-transcriptional means, and we recently reported that LSF directly binds α-tubulin and is present in purified cellular tubulin preparations. Consistent with a microtubule role for LSF, here we show that LSF enhanced the rate of tubulin polymerization in vitro, and FQI1 inhibited such polymerization. To probe whether the FQI1-mediated spindle abnormalities could result from inhibition of mitotic LSF-protein interactions, mass spectrometry was performed using as bait an inducible, tagged form of LSF that is biotinylated by endogenous enzymes. The global proteomics analysis yielded expected associations for a transcription factor, notably with RNA processing machinery, but also to nontranscriptional components. In particular, and consistent with spindle disruption due to FQI treatment, mitotic, FQI1-sensitive interactions were identified between the biotinylated LSF and microtubule-associated proteins that regulate spindle assembly, positioning, and dynamics, as well as centrosome-associated proteins. Probing the mitotic LSF interactome using small molecule inhibitors therefore supported a non-transcriptional role for LSF in mediating progression through mitosis.
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Affiliation(s)
- Sarah A. Yunes
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
| | - Jennifer L. S. Willoughby
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
- Alnylam Pharmaceuticals, Cambridge, Massachusetts, United States of America
| | - Julian H. Kwan
- Department of Biochemistry and Center for Network Systems Biology, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Jessica M. Biagi
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Niranjana Pokharel
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Hang Gyeong Chin
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
- New England Biolabs, Ipswich, Massachusetts, United States of America
| | - Emily A. York
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Kuan-Chung Su
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts, United States of America
| | - Kelly George
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jagesh V. Shah
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Andrew Emili
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Department of Biochemistry and Center for Network Systems Biology, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Scott E. Schaus
- Department of Chemistry and Center for Molecular Discovery, Boston University, Boston, Massachusetts, United States of America
| | - Ulla Hansen
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, Boston, Massachusetts, United States of America
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21
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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: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 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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22
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Andreu I, Granero-Moya I, Chahare NR, Clein K, Molina-Jordán M, Beedle AEM, Elosegui-Artola A, Abenza JF, Rossetti L, Trepat X, Raveh B, Roca-Cusachs P. Mechanical force application to the nucleus regulates nucleocytoplasmic transport. Nat Cell Biol 2022; 24:896-905. [PMID: 35681009 PMCID: PMC7614780 DOI: 10.1038/s41556-022-00927-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 04/26/2022] [Indexed: 12/30/2022]
Abstract
Mechanical force controls fundamental cellular processes in health and disease, and increasing evidence shows that the nucleus both experiences and senses applied forces. Such forces can lead to the nuclear translocation of proteins, but whether force controls nucleocytoplasmic transport, and how, remains unknown. Here we show that nuclear forces differentially control passive and facilitated nucleocytoplasmic transport, setting the rules for the mechanosensitivity of shuttling proteins. We demonstrate that nuclear force increases permeability across nuclear pore complexes, with a dependence on molecular weight that is stronger for passive than for facilitated diffusion. Owing to this differential effect, force leads to the translocation of cargoes into or out of the nucleus within a given range of molecular weight and affinity for nuclear transport receptors. Further, we show that the mechanosensitivity of several transcriptional regulators can be both explained by this mechanism and engineered exogenously by introducing appropriate nuclear localization signals. Our work unveils a mechanism of mechanically induced signalling, probably operating in parallel with others, with potential applicability across signalling pathways.
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Affiliation(s)
- Ion Andreu
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain.
- Universidad de Navarra, TECNUN Escuela de Ingeniería, Donostia-San Sebastián, Spain.
| | - Ignasi Granero-Moya
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
| | - Nimesh R Chahare
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Kessem Clein
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Marc Molina-Jordán
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
| | - Amy E M Beedle
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Department of Physics, King's College London, London, UK
| | - Alberto Elosegui-Artola
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Department of Physics, King's College London, London, UK
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Cell and Tissue Mechanobiology Laboratory, The Francis Crick Institute, London, UK
| | - Juan F Abenza
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Leone Rossetti
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
| | - Xavier Trepat
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain
- Universitat de Barcelona, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - Barak Raveh
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Pere Roca-Cusachs
- Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Technology (BIST), Barcelona, Spain.
- Universitat de Barcelona, Barcelona, Spain.
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23
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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: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [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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24
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β-Arrestin2 Is Critically Involved in the Differential Regulation of Phosphosignaling Pathways by Thyrotropin-Releasing Hormone and Taltirelin. Cells 2022; 11:cells11091473. [PMID: 35563779 PMCID: PMC9103620 DOI: 10.3390/cells11091473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 12/17/2022] Open
Abstract
In recent years, thyrotropin-releasing hormone (TRH) and its analogs, including taltirelin (TAL), have demonstrated a range of effects on the central nervous system that represent potential therapeutic agents for the treatment of various neurological disorders, including neurodegenerative diseases. However, the molecular mechanisms of their actions remain poorly understood. In this study, we investigated phosphosignaling dynamics in pituitary GH1 cells affected by TRH and TAL and the putative role of β-arrestin2 in mediating these effects. Our results revealed widespread alterations in many phosphosignaling pathways involving signal transduction via small GTPases, MAP kinases, Ser/Thr- and Tyr-protein kinases, Wnt/β-catenin, and members of the Hippo pathway. The differential TRH- or TAL-induced phosphorylation of numerous proteins suggests that these ligands exhibit some degree of biased agonism at the TRH receptor. The different phosphorylation patterns induced by TRH or TAL in β-arrestin2-deficient cells suggest that the β-arrestin2 scaffold is a key factor determining phosphorylation events after TRH receptor activation. Our results suggest that compounds that modulate kinase and phosphatase activity can be considered as additional adjuvants to enhance the potential therapeutic value of TRH or TAL.
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25
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Sáinz-Jaspeado M, Smith RO, Plunde O, Pawelzik SC, Jin Y, Nordling S, Ding Y, Aspenström P, Hedlund M, Bastianello G, Ascione F, Li Q, Demir CS, Fernando D, Daniel G, Franco-Cereceda A, Kroon J, Foiani M, Petrova TV, Kilimann MW, Bäck M, Claesson-Welsh L. Palmdelphin Regulates Nuclear Resilience to Mechanical Stress in the Endothelium. Circulation 2021; 144:1629-1645. [PMID: 34636652 PMCID: PMC8589083 DOI: 10.1161/circulationaha.121.054182] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Supplemental Digital Content is available in the text. PALMD (palmdelphin) belongs to the family of paralemmin proteins implicated in cytoskeletal regulation. Single nucleotide polymorphisms in the PALMD locus that result in reduced expression are strong risk factors for development of calcific aortic valve stenosis and predict severity of the disease.
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Affiliation(s)
- Miguel Sáinz-Jaspeado
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
| | - Ross O Smith
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
| | - Oscar Plunde
- Department of Medicine Solna, Karolinska Institutet and Department of Cardiology, Karolinska University Hospital Stockholm, Sweden (O.P., S.-C.P., M.B.)
| | - Sven-Christian Pawelzik
- Department of Medicine Solna, Karolinska Institutet and Department of Cardiology, Karolinska University Hospital Stockholm, Sweden (O.P., S.-C.P., M.B.)
| | - Yi Jin
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
| | - Sofia Nordling
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
| | - Yindi Ding
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
| | - Pontus Aspenström
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
| | - Marie Hedlund
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
| | - Giulia Bastianello
- IFOM-FIRC (institute of molecular oncology - Fondazione italiana per la ricerca sul cancro), Milano, Italy (G.B., F.A., Q.L., M.F.).,University of Milan, Italy (G.B., M.F.)
| | - Flora Ascione
- IFOM-FIRC (institute of molecular oncology - Fondazione italiana per la ricerca sul cancro), Milano, Italy (G.B., F.A., Q.L., M.F.)
| | - Qingsen Li
- IFOM-FIRC (institute of molecular oncology - Fondazione italiana per la ricerca sul cancro), Milano, Italy (G.B., F.A., Q.L., M.F.)
| | - Cansaran Saygili Demir
- Department of Oncology, University of Lausanne, Switzerland (C.S.D., T.V.P.).,Ludwig Institute for Cancer Research Lausanne, Switzerland (C.S.D., T.V.P.)
| | - Dinesh Fernando
- Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, Uppsala (D.F., G.D.)
| | - Geoffrey Daniel
- Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, Uppsala (D.F., G.D.)
| | - Anders Franco-Cereceda
- Department of Molecular Medicine and Surgery, Karolinska Institutet, and Department of Cardiothoracic Surgery, Karolinska University Hospital, Stockholm, Sweden (A.F.-C.)
| | - Jeffrey Kroon
- Department of Experimental Vascular Medicine, Amsterdam Cardiovascular Sciences, University of Amsterdam, Amsterdam University Medical Center, The Netherlands (J.K.)
| | - Marco Foiani
- IFOM-FIRC (institute of molecular oncology - Fondazione italiana per la ricerca sul cancro), Milano, Italy (G.B., F.A., Q.L., M.F.).,University of Milan, Italy (G.B., M.F.)
| | - Tatiana V Petrova
- Department of Oncology, University of Lausanne, Switzerland (C.S.D., T.V.P.).,Ludwig Institute for Cancer Research Lausanne, Switzerland (C.S.D., T.V.P.)
| | - Manfred W Kilimann
- Department of Neuroscience (M.W.K.), Uppsala University, Sweden.,Department of Molecular Neurobiology, Max Planck Institute for Experimental Medicine, Göttingen, Germany (M.W.K.)
| | - Magnus Bäck
- Department of Medicine Solna, Karolinska Institutet and Department of Cardiology, Karolinska University Hospital Stockholm, Sweden (O.P., S.-C.P., M.B.)
| | - Lena Claesson-Welsh
- Rudbeck, Beijer and SciLifeLab Laboratories, Department of Immunology, Genetics and Pathology (M.S.-J., R.O.S., Y.J., S.N., Y.D., P.A., M.H., L.C.-W.), Uppsala University, Sweden
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26
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Hirsch AG, Becker D, Lamping JP, Krebber H. Unraveling the stepwise maturation of the yeast telomerase including a Cse1 and Mtr10 mediated quality control checkpoint. Sci Rep 2021; 11:22174. [PMID: 34773052 PMCID: PMC8590012 DOI: 10.1038/s41598-021-01599-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 10/29/2021] [Indexed: 01/17/2023] Open
Abstract
Telomerases elongate the ends of chromosomes required for cell immortality through their reverse transcriptase activity. By using the model organism Saccharomyces cerevisiae we defined the order in which the holoenzyme matures. First, a longer precursor of the telomerase RNA, TLC1 is transcribed and exported into the cytoplasm, where it associates with the protecting Sm-ring, the Est and the Pop proteins. This partly matured telomerase is re-imported into the nucleus via Mtr10 and a novel TLC1-import factor, the karyopherin Cse1. Remarkably, while mutations in all known transport factors result in short telomere ends, mutation in CSE1 leads to the amplification of Y′ elements in the terminal chromosome regions and thus elongated telomere ends. Cse1 does not only support TLC1 import, but also the Sm-ring stabilization on the RNA enableling Mtr10 contact and nuclear import. Thus, Sm-ring formation and import factor contact resembles a quality control step in the maturation process of the telomerase. The re-imported immature TLC1 is finally trimmed into the 1158 nucleotides long mature form via the nuclear exosome. TMG-capping of TLC1 finalizes maturation, leading to mature telomerase.
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Affiliation(s)
- Anna Greta Hirsch
- Abteilung für Molekulare Genetik, Institut für Mikrobiologie Und Genetik, Göttinger Zentrum für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany
| | - Daniel Becker
- Philipps-Universität Marburg, Klinik für Dermatologie Und Allergologie, Baldingerstraße, 35043, Marburg, Germany
| | - Jan-Philipp Lamping
- Abteilung für Molekulare Genetik, Institut für Mikrobiologie Und Genetik, Göttinger Zentrum für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany
| | - Heike Krebber
- Abteilung für Molekulare Genetik, Institut für Mikrobiologie Und Genetik, Göttinger Zentrum für Molekulare Biowissenschaften (GZMB), Georg-August Universität Göttingen, Göttingen, Germany.
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27
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Afinanisa Q, Cho MK, Seong HA. AMPK Localization: A Key to Differential Energy Regulation. Int J Mol Sci 2021; 22:10921. [PMID: 34681581 PMCID: PMC8535671 DOI: 10.3390/ijms222010921] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/05/2021] [Accepted: 10/07/2021] [Indexed: 11/23/2022] Open
Abstract
As the central node between nutrition signaling input and the metabolic pathway, AMP-activated protein kinase (AMPK) is tightly regulated to maintain energy homeostasis. Subcellular compartmentalization of AMPK is one of the critical regulations that enables AMPK to access proper targets and generate appropriate responses to specific perturbations and different levels of stress. One of the characterized localization mechanisms is RanGTPase-driven CRM1 that recognizes the nuclear export sequence (NES) on the α subunit to translocate AMPK into the cytoplasm. Nuclear localization putatively employs RanGTPase-driven importin that might recognize the nuclear localization signal (NLS) present on the AMPKα2 kinase domain. Nucleo-cytoplasmic shuttling of AMPK is influenced by multiple factors, such as starvation, exercise, heat shock, oxidant, cell density, and circadian rhythm. Tissue-specific localization, which distributes AMPK trimers with different combinations, has also been shown to be vital in maintaining tissue-specific metabolism. Tissue-specific and subcellular distribution of AMPK might be attributed to differences in the expression of the subunit, the stabilization by protein regulators, tissue activity, and the localization of AMPK activators. Considering the importance of AMPK localization in coordinating signaling and metabolism, further research is due to fully elucidate the largely unknown complex mechanism underlying this regulation.
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Affiliation(s)
| | | | - Hyun-A Seong
- Department of Biochemistry, School of Biological Sciences, Chungbuk National University, Cheongju 28644, Korea; (Q.A.); (M.K.C.)
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28
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Liu X, Zhang Z, Zhang M, Zhao X, Zhang T, Liu W, Zhang J. A ras-related nuclear protein Ran participates in the 20E signaling pathway and is essential for the growth and development of Locusta migratoria. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2021; 178:104945. [PMID: 34446211 DOI: 10.1016/j.pestbp.2021.104945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/25/2021] [Accepted: 07/29/2021] [Indexed: 06/13/2023]
Abstract
The small GTPase Ran is a member of the Ras superfamily of small GTP-binding proteins, which plays a key role in the translocation of RNA and proteins through the nuclear pore complex. In this study, the full-length cDNA sequence of LmRan gene was obtained, which consists of 648-nucleotides open reading frame (ORF) and encodes 215 amino acids. RT-qPCR results revealed that LmRan was expressed in all developmental days and tissues investigated. Injection of dsLmRan into 4th and 5th instar nymphs, resulted in a significant down-regulation of LmRan transcripts, respectively. All dsLmRan-injected nymphs died before molting. Further hematoxylin and eosin staining of the integument showed that there was no apolysis occurred after silencing LmRan. In addition, the weight of dsLmRan-injected nymphs was significantly lower than that of the control group, and the gastric caecum and midgut was severely smaller. Especiallly, the mRNA level of LmCYP302a1, LmCYP315a1 and LmCYP314a1 responsible for 20E synthesis, LmE75 and LmE74 genes involved in the 20E signaling pathway, LmGfat, LmUAP1 and LmCHT10 genes involved in chitin metabolism pathway were dramatically decreased in the dsLmRan-injected nymphs. Together, the results indicated that LmRan participate in the 20E signaling pathway, which is essential for the growth and development of locusts.
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Affiliation(s)
- Xiaojian Liu
- Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Zheng Zhang
- Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Min Zhang
- Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Xiaoming Zhao
- Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Tingting Zhang
- Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Weimin Liu
- Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Jianzhen Zhang
- Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China.
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29
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Marretta AL, Di Lorenzo G, Ribera D, Cannella L, von Arx C, Bracigliano A, Clemente O, Tafuto R, Pizzolorusso A, Tafuto S. Selinexor and the Selective Inhibition of Nuclear Export: A New Perspective on the Treatment of Sarcomas and Other Solid and Non-Solid Tumors. Pharmaceutics 2021; 13:pharmaceutics13091522. [PMID: 34575598 PMCID: PMC8466603 DOI: 10.3390/pharmaceutics13091522] [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: 07/06/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 12/05/2022] Open
Abstract
Nucleocytoplasmic transport has been found dysregulated in many types of cancer and is often described as a poor prognostic factor. Specifically, Exportin-1 (XPO1) has been found overexpressed in many tumors and has become an attractive target in molecular oncology and therapeutics development. The selective inhibitor of nuclear export, Selinexor, is one of the most scientifically interesting drugs that targets XPO1 in clinical development. In this review, we summarized the most relevant preclinical and clinical results achieved for non-solid tumors, sarcomas, and other kind of solid tumors.
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Affiliation(s)
- Antonella Lucia Marretta
- Department of Clinical and Surgery Oncology Unit, University of Naples “Federico II”, Via S. Pansini 5, 80131 Naples, Italy;
| | - Giuseppe Di Lorenzo
- Sarcomas and Rare Tumors Unit, Istituto Nazionale Tumori—IRCCS, Fondazione “G. Pascale”, 80131 Naples, Italy; (G.D.L.); (L.C.); (O.C.); (A.P.); (S.T.)
| | - Dario Ribera
- Department of Clinical and Surgery Oncology Unit, University of Naples “Federico II”, Via S. Pansini 5, 80131 Naples, Italy;
- Correspondence:
| | - Lucia Cannella
- Sarcomas and Rare Tumors Unit, Istituto Nazionale Tumori—IRCCS, Fondazione “G. Pascale”, 80131 Naples, Italy; (G.D.L.); (L.C.); (O.C.); (A.P.); (S.T.)
| | - Claudia von Arx
- Department of Breast and Thoracic Oncology, Division of Breast Medical Oncology, Istituto Nazionale Tumori—IRCCS, Fondazione “G. Pascale”, 80131 Naples, Italy;
| | - Alessandra Bracigliano
- Nuclear Medicine Unit, Istituto Nazionale Tumori—IRCCS, Fondazione “G. Pascale”, Via M. Semmola 53, 80131 Naples, Italy;
| | - Ottavia Clemente
- Sarcomas and Rare Tumors Unit, Istituto Nazionale Tumori—IRCCS, Fondazione “G. Pascale”, 80131 Naples, Italy; (G.D.L.); (L.C.); (O.C.); (A.P.); (S.T.)
| | - Roberto Tafuto
- Division of Neurosurgery, University of Naples “Federico II”, Via S. Pansini 5, 80131 Naples, Italy;
| | - Antonio Pizzolorusso
- Sarcomas and Rare Tumors Unit, Istituto Nazionale Tumori—IRCCS, Fondazione “G. Pascale”, 80131 Naples, Italy; (G.D.L.); (L.C.); (O.C.); (A.P.); (S.T.)
| | - Salvatore Tafuto
- Sarcomas and Rare Tumors Unit, Istituto Nazionale Tumori—IRCCS, Fondazione “G. Pascale”, 80131 Naples, Italy; (G.D.L.); (L.C.); (O.C.); (A.P.); (S.T.)
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30
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Shen Q, Wang YE, Palazzo AF. Crosstalk between nucleocytoplasmic trafficking and the innate immune response to viral infection. J Biol Chem 2021; 297:100856. [PMID: 34097873 PMCID: PMC8254040 DOI: 10.1016/j.jbc.2021.100856] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/24/2021] [Accepted: 06/03/2021] [Indexed: 12/16/2022] Open
Abstract
The nuclear pore complex is the sole gateway connecting the nucleoplasm and cytoplasm. In humans, the nuclear pore complex is one of the largest multiprotein assemblies in the cell, with a molecular mass of ∼110 MDa and consisting of 8 to 64 copies of about 34 different nuclear pore proteins, termed nucleoporins, for a total of 1000 subunits per pore. Trafficking events across the nuclear pore are mediated by nuclear transport receptors and are highly regulated. The nuclear pore complex is also used by several RNA viruses and almost all DNA viruses to access the host cell nucleoplasm for replication. Viruses hijack the nuclear pore complex, and nuclear transport receptors, to access the nucleoplasm where they replicate. In addition, the nuclear pore complex is used by the cell innate immune system, a network of signal transduction pathways that coordinates the first response to foreign invaders, including viruses and other pathogens. Several branches of this response depend on dynamic signaling events that involve the nuclear translocation of downstream signal transducers. Mounting evidence has shown that these signaling cascades, especially those steps that involve nucleocytoplasmic trafficking events, are targeted by viruses so that they can evade the innate immune system. This review summarizes how nuclear pore proteins and nuclear transport receptors contribute to the innate immune response and highlights how viruses manipulate this cellular machinery to favor infection. A comprehensive understanding of nuclear pore proteins in antiviral innate immunity will likely contribute to the development of new antiviral therapeutic strategies.
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Affiliation(s)
- Qingtang Shen
- School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China.
| | - Yifan E Wang
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Alexander F Palazzo
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
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31
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Sajidah ES, Lim K, Wong RW. How SARS-CoV-2 and Other Viruses Build an Invasion Route to Hijack the Host Nucleocytoplasmic Trafficking System. Cells 2021; 10:1424. [PMID: 34200500 PMCID: PMC8230057 DOI: 10.3390/cells10061424] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/31/2021] [Accepted: 06/03/2021] [Indexed: 12/14/2022] Open
Abstract
The host nucleocytoplasmic trafficking system is often hijacked by viruses to accomplish their replication and to suppress the host immune response. Viruses encode many factors that interact with the host nuclear transport receptors (NTRs) and the nucleoporins of the nuclear pore complex (NPC) to access the host nucleus. In this review, we discuss the viral factors and the host factors involved in the nuclear import and export of viral components. As nucleocytoplasmic shuttling is vital for the replication of many viruses, we also review several drugs that target the host nuclear transport machinery and discuss their feasibility for use in antiviral treatment.
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Affiliation(s)
- Elma Sakinatus Sajidah
- Division of Nano Life Science in the Graduate School of Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan;
| | - Keesiang Lim
- WPI-Nano Life Science Institute, Kanazawa University, Kanazawa 920-1192, Japan
| | - Richard W. Wong
- Division of Nano Life Science in the Graduate School of Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan;
- WPI-Nano Life Science Institute, Kanazawa University, Kanazawa 920-1192, Japan
- Cell-Bionomics Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan
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32
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Lee CH, Hawker NP, Peters JR, Lonhienne TGA, Gursanscky NR, Matthew L, Brosnan CA, Mann CWG, Cromer L, Taochy C, Ngo QA, Sundaresan V, Schenk PM, Kobe B, Borges F, Mercier R, Bowman JL, Carroll BJ. DEFECTIVE EMBRYO AND MERISTEMS genes are required for cell division and gamete viability in Arabidopsis. PLoS Genet 2021; 17:e1009561. [PMID: 33999950 PMCID: PMC8158957 DOI: 10.1371/journal.pgen.1009561] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/27/2021] [Accepted: 04/21/2021] [Indexed: 11/19/2022] Open
Abstract
The DEFECTIVE EMBRYO AND MERISTEMS 1 (DEM1) gene encodes a protein of unknown biochemical function required for meristem formation and seedling development in tomato, but it was unclear whether DEM1’s primary role was in cell division or alternatively, in defining the identity of meristematic cells. Genome sequence analysis indicates that flowering plants possess at least two DEM genes. Arabidopsis has two DEM genes, DEM1 and DEM2, which we show are expressed in developing embryos and meristems in a punctate pattern that is typical of genes involved in cell division. Homozygous dem1 dem2 double mutants were not recovered, and plants carrying a single functional DEM1 allele and no functional copies of DEM2, i.e. DEM1/dem1 dem2/dem2 plants, exhibit normal development through to the time of flowering but during male reproductive development, chromosomes fail to align on the metaphase plate at meiosis II and result in abnormal numbers of daughter cells following meiosis. Additionally, these plants show defects in both pollen and embryo sac development, and produce defective male and female gametes. In contrast, dem1/dem1 DEM2/dem2 plants showed normal levels of fertility, indicating that DEM2 plays a more important role than DEM1 in gamete viability. The increased importance of DEM2 in gamete viability correlated with higher mRNA levels of DEM2 compared to DEM1 in most tissues examined and particularly in the vegetative shoot apex, developing siliques, pollen and sperm. We also demonstrate that gamete viability depends not only on the number of functional DEM alleles inherited following meiosis, but also on the number of functional DEM alleles in the parent plant that undergoes meiosis. Furthermore, DEM1 interacts with RAS-RELATED NUCLEAR PROTEIN 1 (RAN1) in yeast two-hybrid and pull-down binding assays, and we show that fluorescent proteins fused to DEM1 and RAN1 co-localize transiently during male meiosis and pollen development. In eukaryotes, RAN is a highly conserved GTPase that plays key roles in cell cycle progression, spindle assembly during cell division, reformation of the nuclear envelope following cell division, and nucleocytoplasmic transport. Our results demonstrate that DEM proteins play an essential role in cell division in plants, most likely through an interaction with RAN1. Up to half of the genes predicted from genome projects lack a known biological and biochemical function. Many of these genes are likely to play essential roles but it is difficult to reveal their function because minor changes in the genetic sequence can result in lethality and genetic redundancy can obscure analysis. Genome projects predict that flowering plants have at least two DEM genes that encode a protein of unknown cellular and biochemical function. In this paper, we use multiple combinations of dem mutants in Arabidopsis to show that DEM genes are essential for cell division and gamete viability. Interestingly, gamete viability depends not only on the number of functional copies of DEM genes in the gametes, but also on the number of functional copies of DEM genes in the parent plant that produces the gametes. We also show that DEM proteins interact with RAN, a highly conserved protein that controls cell division in all eukaryotic organisms.
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Affiliation(s)
- Chin Hong Lee
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
| | - Nathaniel P. Hawker
- Section of Plant Biology, One Shields Avenue, University of California at Davis, Davis, California, United States of America
| | - Jonathan R. Peters
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
| | - Thierry G. A. Lonhienne
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
| | - Nial R. Gursanscky
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
| | - Louisa Matthew
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
| | - Christopher A. Brosnan
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
| | - Christopher W. G. Mann
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
| | - Laurence Cromer
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Christelle Taochy
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Quy A. Ngo
- Section of Plant Biology, One Shields Avenue, University of California at Davis, Davis, California, United States of America
| | - Venkatesan Sundaresan
- Section of Plant Biology, One Shields Avenue, University of California at Davis, Davis, California, United States of America
| | - Peer M. Schenk
- School of Agriculture and Food Sciences, The University of Queensland, St. Lucia, Australia
| | - Bostjan Kobe
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
- Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, Australia
| | - Filipe Borges
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Raphael Mercier
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
- Department of Chromosome Biology, Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - John L. Bowman
- Section of Plant Biology, One Shields Avenue, University of California at Davis, Davis, California, United States of America
- School of Biological Sciences, Monash University, Clayton Campus, Clayton, Victoria, Australia
- * E-mail: (JLB); (BJC)
| | - Bernard J. Carroll
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Australia
- * E-mail: (JLB); (BJC)
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33
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Tsai YL, Manley JL. Multiple ways to a dead end: diverse mechanisms by which ALS mutant genes induce cell death. Cell Cycle 2021; 20:631-646. [PMID: 33722167 DOI: 10.1080/15384101.2021.1886661] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a deadly neuromuscular disorder caused by progressive motor neuron loss in the brain and spinal cord. Over the past decades, a number of genetic mutations have been identified that cause or are associated with ALS disease progression. Numerous genes harbor ALS mutations, and they encode proteins displaying a wide range of physiological functions, with limited overlap. Despite the divergent functions, mutations in these genes typically trigger protein aggregation, which can confer gain- and/or loss-of-function to a number of essential cellular processes. Nuclear processes such as mRNA splicing and the response to DNA damage are significantly affected in ALS patients. Cytoplasmic organelles such as mitochondria are damaged by ALS mutant proteins. Processes that maintain cellular homeostasis such as autophagy, nonsense-mediated mRNA decay and nucleocytoplasmic transport, are also impaired by ALS mutations. Here, we review the multiple mechanisms by which mutations in major ALS-associated genes, such as TARDBP, C9ORF72 and FUS, lead to impairment of essential cellular processes.
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Affiliation(s)
- Yueh-Lin Tsai
- Department of Biological Sciences, Columbia University, New York, NY, United States
| | - James L Manley
- Department of Biological Sciences, Columbia University, New York, NY, United States
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34
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Mboukou A, Rajendra V, Kleinova R, Tisné C, Jantsch MF, Barraud P. Transportin-1: A Nuclear Import Receptor with Moonlighting Functions. Front Mol Biosci 2021; 8:638149. [PMID: 33681296 PMCID: PMC7930572 DOI: 10.3389/fmolb.2021.638149] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 01/13/2021] [Indexed: 12/11/2022] Open
Abstract
Transportin-1 (Trn1), also known as karyopherin-β2 (Kapβ2), is probably the best-characterized nuclear import receptor of the karyopherin-β family after Importin-β, but certain aspects of its functions in cells are still puzzling or are just recently emerging. Since the initial identification of Trn1 as the nuclear import receptor of hnRNP A1 ∼25 years ago, several molecular and structural studies have unveiled and refined our understanding of Trn1-mediated nuclear import. In particular, the understanding at a molecular level of the NLS recognition by Trn1 made a decisive step forward with the identification of a new class of NLSs called PY-NLSs, which constitute the best-characterized substrates of Trn1. Besides PY-NLSs, many Trn1 cargoes harbour NLSs that do not resemble the archetypical PY-NLS, which complicates the global understanding of cargo recognition by Trn1. Although PY-NLS recognition is well established and supported by several structures, the recognition of non-PY-NLSs by Trn1 is far less understood, but recent reports have started to shed light on the recognition of this type of NLSs. Aside from its principal and long-established activity as a nuclear import receptor, Trn1 was shown more recently to moonlight outside nuclear import. Trn1 has for instance been caught in participating in virus uncoating, ciliary transport and in modulating the phase separation properties of aggregation-prone proteins. Here, we focus on the structural and functional aspects of Trn1-mediated nuclear import, as well as on the moonlighting activities of Trn1.
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Affiliation(s)
- Allegra Mboukou
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique (IBPC), UMR 8261, CNRS, Université de Paris, Paris, France
| | - Vinod Rajendra
- Department of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Renata Kleinova
- Department of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Carine Tisné
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique (IBPC), UMR 8261, CNRS, Université de Paris, Paris, France
| | - Michael F. Jantsch
- Department of Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - Pierre Barraud
- Expression Génétique Microbienne, Institut de Biologie Physico-Chimique (IBPC), UMR 8261, CNRS, Université de Paris, Paris, France
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35
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Samer S, Raman R, Laube G, Kreutz MR, Karpova A. The nuclear lamina is a hub for the nuclear function of Jacob. Mol Brain 2021; 14:9. [PMID: 33436037 PMCID: PMC7802242 DOI: 10.1186/s13041-020-00722-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 12/26/2020] [Indexed: 12/23/2022] Open
Abstract
Jacob is a synapto-nuclear messenger protein that couples NMDAR activity to CREB-dependent gene expression. In this study, we investigated the nuclear distribution of Jacob and report a prominent targeting to the nuclear envelope that requires NMDAR activity and nuclear import. Immunogold electron microscopy and proximity ligation assay combined with STED imaging revealed preferential association of Jacob with the inner nuclear membrane where it directly binds to LaminB1, an intermediate filament and core component of the inner nuclear membrane (INM). The association with the INM is transient; it involves a functional nuclear export signal in Jacob and a canonical CRM1-RanGTP-dependent export mechanism that defines the residing time of the protein at the INM. Taken together, the data suggest a stepwise redistribution of Jacob within the nucleus following nuclear import and prior to nuclear export.
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Affiliation(s)
- Sebastian Samer
- RG Neuroplasticity, Leibniz Institute for Neurobiology, 39118, Magdeburg, Germany
| | - Rajeev Raman
- RG Neuroplasticity, Leibniz Institute for Neurobiology, 39118, Magdeburg, Germany
| | - Gregor Laube
- RG Neuroplasticity, Leibniz Institute for Neurobiology, 39118, Magdeburg, Germany
| | - Michael R Kreutz
- RG Neuroplasticity, Leibniz Institute for Neurobiology, 39118, Magdeburg, Germany.
- Center for Behavioral Brain Sciences, Otto Von Guericke University, 39106, Magdeburg, Germany.
- Leibniz Group 'Dendritic Organelles and Synaptic Function', Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251, Hamburg, Germany.
| | - Anna Karpova
- RG Neuroplasticity, Leibniz Institute for Neurobiology, 39118, Magdeburg, Germany.
- Center for Behavioral Brain Sciences, Otto Von Guericke University, 39106, Magdeburg, Germany.
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36
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Xu X, Su Y, Zou Z, Zhou Y, Yan J. Correlation between C9ORF72 mutation and neurodegenerative diseases: A comprehensive review of the literature. Int J Med Sci 2021; 18:378-386. [PMID: 33390807 PMCID: PMC7757155 DOI: 10.7150/ijms.53550] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 11/09/2020] [Indexed: 12/13/2022] Open
Abstract
Chromosome 9 open reading frame 72 (C9ORF72) encodes a 54-kDa protein with unknown function that is expressed at high levels in the central nervous system. The C9ORF72 hexanucleotide amplification is one of the most recently discovered repetitive amplification diseases related to neurodegeneration. Its association with amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) spectrum diseases has been fully established, although a causative role for C9ORF72 in Alzheimer's disease (AD) and Parkinson's disease (PD) remains to be established. Therefore, in this article, we will review the evidence for C9ORF72 as a causative factor in neurodegenerative diseases, the underlying mechanisms, and the potential for targeting C9ORF72 as a strategy to alleviate neurodegenerative disease progression.
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Affiliation(s)
- Xingfeng Xu
- Faculty of Basic Medical Sciences, Guilin Medical University, Guilin, 541004, Guangxi, China.,Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, 541004, Guangxi, China
| | - Yan Su
- Faculty of Basic Medical Sciences, Guilin Medical University, Guilin, 541004, Guangxi, China.,Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, 541004, Guangxi, China
| | - Zhenyou Zou
- Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, 541004, Guangxi, China
| | - Yali Zhou
- Faculty of Basic Medical Sciences, Guilin Medical University, Guilin, 541004, Guangxi, China
| | - Jianguo Yan
- Faculty of Basic Medical Sciences, Guilin Medical University, Guilin, 541004, Guangxi, China.,Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin, 541004, Guangxi, China
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37
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Tsuchiya K, Hayashi H, Nishina M, Okumura M, Sato Y, Kanemaki MT, Goshima G, Kiyomitsu T. Ran-GTP Is Non-essential to Activate NuMA for Mitotic Spindle-Pole Focusing but Dynamically Polarizes HURP Near Chromosomes. Curr Biol 2021; 31:115-127.e3. [DOI: 10.1016/j.cub.2020.09.091] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/25/2020] [Accepted: 09/30/2020] [Indexed: 12/27/2022]
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38
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Lee J, Park J, Kim JH, Lee G, Park TE, Yoon KJ, Kim YK, Lim C. LSM12-EPAC1 defines a neuroprotective pathway that sustains the nucleocytoplasmic RAN gradient. PLoS Biol 2020; 18:e3001002. [PMID: 33362237 PMCID: PMC7757817 DOI: 10.1371/journal.pbio.3001002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 11/19/2020] [Indexed: 02/07/2023] Open
Abstract
Nucleocytoplasmic transport (NCT) defects have been implicated in neurodegenerative diseases such as C9ORF72-associated amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). Here, we identify a neuroprotective pathway of like-Sm protein 12 (LSM12) and exchange protein directly activated by cyclic AMP 1 (EPAC1) that sustains the nucleocytoplasmic RAN gradient and thereby suppresses NCT dysfunction by the C9ORF72-derived poly(glycine-arginine) protein. LSM12 depletion in human neuroblastoma cells aggravated poly(GR)-induced impairment of NCT and nuclear integrity while promoting the nuclear accumulation of poly(GR) granules. In fact, LSM12 posttranscriptionally up-regulated EPAC1 expression, whereas EPAC1 overexpression rescued the RAN gradient and NCT defects in LSM12-deleted cells. C9-ALS patient-derived neurons differentiated from induced pluripotent stem cells (C9-ALS iPSNs) displayed low expression of LSM12 and EPAC1. Lentiviral overexpression of LSM12 or EPAC1 indeed restored the RAN gradient, mitigated the pathogenic mislocalization of TDP-43, and suppressed caspase-3 activation for apoptosis in C9-ALS iPSNs. EPAC1 depletion biochemically dissociated RAN-importin β1 from the cytoplasmic nuclear pore complex, thereby dissipating the nucleocytoplasmic RAN gradient essential for NCT. These findings define the LSM12-EPAC1 pathway as an important suppressor of the NCT-related pathologies in C9-ALS/FTD. A post-transcriptional circuit comprising LSM12 and EPAC1 suppresses neurodegenerative pathologies in C9ORF72-associated amyotrophic lateral sclerosis by establishing the RAN gradient and sustaining nucleocytoplasmic transport.
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Affiliation(s)
- Jongbo Lee
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Jumin Park
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Ji-hyung Kim
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Giwook Lee
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Tae-Eun Park
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Ki-Jun Yoon
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Yoon Ki Kim
- Creative Research Initiatives Center for Molecular Biology of Translation, Korea University, Seoul, Republic of Korea
- Division of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Chunghun Lim
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
- * E-mail:
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39
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Pulupa J, Prior H, Johnson DS, Simon SM. Conformation of the nuclear pore in living cells is modulated by transport state. eLife 2020; 9:e60654. [PMID: 33346731 PMCID: PMC7752133 DOI: 10.7554/elife.60654] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/23/2020] [Indexed: 12/15/2022] Open
Abstract
While the static structure of the nuclear pore complex (NPC) continues to be refined with cryo-EM and x-ray crystallography, in vivo conformational changes of the NPC remain under-explored. We developed sensors that report on the orientation of NPC components by rigidly conjugating mEGFP to different NPC proteins. Our studies show conformational changes to select domains of nucleoporins (Nups) within the inner ring (Nup54, Nup58, Nup62) when transport through the NPC is perturbed and no conformational changes to Nups elsewhere in the NPC. Our results suggest that select components of the NPC are flexible and undergo conformational changes upon engaging with cargo.
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Affiliation(s)
- Joan Pulupa
- Laboratory of Cellular Biophysics, Rockefeller UniversityNew YorkUnited States
| | - Harriet Prior
- Laboratory of Cellular Biophysics, Rockefeller UniversityNew YorkUnited States
| | - Daniel S Johnson
- Department of Physics and Astronomy, Hofstra UniversityHempsteadUnited States
| | - Sanford M Simon
- Laboratory of Cellular Biophysics, Rockefeller UniversityNew YorkUnited States
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40
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Chang CC, Hsia KC. More than a zip code: global modulation of cellular function by nuclear localization signals. FEBS J 2020; 288:5569-5585. [PMID: 33296547 DOI: 10.1111/febs.15659] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 12/27/2022]
Abstract
Extensive structural and functional studies have been carried out in the field of nucleocytoplasmic transport. Nuclear transport factors, such as Importin-α/-β, recognize nuclear localization signals (NLSs) on cargo, and together with the small GTPase Ran, facilitate their nuclear localization. However, it is now emerging that binding of nuclear transport factors to NLSs not only mediates nuclear transport but also contributes to a variety of cellular functions in eukaryotes. Here, we describe recent advances that reveal how NLSs facilitate diverse cellular functions beyond nuclear transport activity. We review separately NLS-mediated regulatory mechanisms at different levels of biological organization, including (a) assembly of higher-order structures; (b) cellular organelle dynamics; and (c) modulation of cellular stress responses and viral infections. Finally, we provide mechanistic insights into how NLSs can regulate such a broad range of functions via their structural and biochemical properties.
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Affiliation(s)
- Chih-Chia Chang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Kuo-Chiang Hsia
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Institute of Biochemistry and Molecular Biology, College of Life Sciences, National Yang-Ming University, Taipei, Taiwan
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41
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Emerging molecular functions and novel roles for the DEAD-box protein Dbp5/DDX19 in gene expression. Cell Mol Life Sci 2020; 78:2019-2030. [PMID: 33205304 DOI: 10.1007/s00018-020-03680-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/21/2020] [Accepted: 10/06/2020] [Indexed: 12/23/2022]
Abstract
The DEAD-box protein (DBP) Dbp5, a member of the superfamily II (SFII) helicases, has multiple reported roles in gene expression. First identified as an essential regulator of mRNA export in Saccharomyces cerevisiae, the enzyme now has reported functions in non-coding RNA export, translation, transcription, and DNA metabolism. Localization of the protein to various cellular compartments (nucleoplasm, nuclear envelope, and cytoplasm) highlights the ability of Dbp5 to modulate different stages of the RNA lifecycle. While Dbp5 has been well studied for > 20 years, several critical questions remain regarding the mechanistic principles that govern Dbp5 localization, substrate selection, and functions in gene expression. This review aims to take a holistic view of the proposed functions of Dbp5 and evaluate models that accommodate current published data.
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42
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Lange A, Fasken MB, Stewart M, Corbett AH. Dissecting the roles of Cse1 and Nup2 in classical NLS-cargo release in vivo. Traffic 2020; 21:622-635. [PMID: 32734712 PMCID: PMC7891619 DOI: 10.1111/tra.12759] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 07/24/2020] [Accepted: 07/26/2020] [Indexed: 01/26/2023]
Abstract
The importin α/β transport machinery mediates the nuclear import of cargo proteins that bear a classical nuclear localization sequence (cNLS). These cargo proteins are linked to the major nuclear protein import factor, importin‐β, by the importin‐α adapter, after which cargo/carrier complexes enter the nucleus through nuclear pores. In the nucleus, cargo is released by the action of RanGTP and the nuclear pore protein Nup2, after which the importins are recycled to the cytoplasm for further transport cycles. The nuclear export of importin‐α is mediated by Cse1/CAS. Here, we exploit structures of functionally important complexes to identify residues that are critical for these interactions and provide insight into how cycles of protein import and recycling of importin‐α occur in vivo using a Saccharomyces cerevisiae model. We examine how these molecular interactions impact protein localization, cargo import, function and complex formation. We show that reversing the charge of key residues in importin‐α (Arg44) or Cse1 (Asp220) results in loss of function of the respective proteins and impairs complex formation both in vitro and in vivo. To extend these results, we show that basic residues in the Nup2 N‐terminus are required for both Nup2 interaction with importin‐α and Nup2 function. These results provide a more comprehensive mechanistic model of how Cse1, RanGTP and Nup2 function in concert to mediate cNLS‐cargo release in the nucleus. Directional transport of cargoes between the nucleus and cytoplasm is mediated by receptors that bind cargo in one compartment and release cargo into a destination compartment. Cargoes that contain a cNLS are recognized by importin‐α in the cytoplasm. Release factors including the importin‐α export receptor, Cse1, and a nuclear pore complex protein, Nup2, ensure efficient cargo delivery into the nucleus. Interactions defined by previous structural studies are required for productive interactions between importin‐α, Cse1, and Nup2 to occur in vivo.
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Affiliation(s)
- Allison Lange
- Department of Biology, Emory University, Atlanta, Georgia, USA
| | - Milo B Fasken
- Department of Biology, Emory University, Atlanta, Georgia, USA
| | - Murray Stewart
- Cambridge Biomedical Campus, MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Anita H Corbett
- Department of Biology, Emory University, Atlanta, Georgia, USA
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Nagi K, Kaur S, Bai Y, Shenoy SK. In-frame fusion of SUMO1 enhances βarrestin2's association with activated GPCRs as well as with nuclear pore complexes. Cell Signal 2020; 75:109759. [PMID: 32860951 DOI: 10.1016/j.cellsig.2020.109759] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/17/2020] [Accepted: 08/22/2020] [Indexed: 01/11/2023]
Abstract
Small ubiquitin like modifier (SUMO) conjugation or SUMOylation of βarrestin2 promotes its association with the clathrin adaptor protein AP2 and facilitates rapid β2 adrenergic receptor (β2AR) internalization. However, disruption of the consensus SUMOylation site in βarrestin2, did not prevent βarrestin2's association with activated β2ARs, dopamine D2 receptors (D2Rs), angiotensin type 1a receptors (AT1aRs) and V2 vasopressin receptors (V2Rs). To address the role of SUMOylation in the trafficking of βarrestin and GPCR complexes, we generated and characterized a yellow fluorescent protein (YFP) tagged βarrestin2-SUMO1 chimeric protein, which is resistant to de-SUMOylation. In HEK-293 cells, YFP-SUMO1 predominantly localized in the nucleus, whereas YFP-βarrestin2 is cytoplasmic. YFP-βarrestin2-SUMO1 in addition to being cytoplasmic, is localized at the nuclear membrane. Nonetheless, βarrestin2-SUMO1 associated robustly with agonist-activated β2ARs as evaluated by co-immunoprecipitation, confocal microscopy and bioluminescence resonance energy transfer (BRET). βarrestin2-SUMO1 associated strongly with the D2R, which forms transient complexes with βarrestin2. But, βarrestin2-SUMO1 and βarrestin2 showed equivalent binding with the V2R, which forms stable complexes with βarrestin2. βarrestin2 expression level directly correlated with the steady state levels of the unmodified form of RanGAP1, which upon SUMOylation associates with nuclear membrane. On the other hand, βarrestin2-SUMO1 not only localized at the nuclear membrane, but also formed a macromolecular complex with RanGAP1. Taken together, our data suggest that SUMOylation of βarrestin2 promotes its protein interactions at both cell and nuclear membranes. Furthermore, βarrestin2-SUMO1 presents as a useful tool to characterize βarrestin2 recruitment to GPCRs, which form transient and unstable complex with βarrestin2.
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Affiliation(s)
- Karim Nagi
- Department of Medicine, Division of Cardiology, Duke University Medical Center, Durham, NC 27710, USA; College of Medicine, QU Health, Qatar University, Doha, Qatar
| | - Suneet Kaur
- Department of Medicine, Division of Cardiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Yushi Bai
- Department of Medicine, Division of Cardiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Sudha K Shenoy
- Department of Medicine, Division of Cardiology, Duke University Medical Center, Durham, NC 27710, USA; Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
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Shi X, Wu J, Mensah RA, Tian N, Liu J, Liu F, Chen J, Che J, Guo Y, Wu B, Zhong G, Cheng C. Genome-Wide Identification and Characterization of UTR-Introns of Citrus sinensis. Int J Mol Sci 2020; 21:E3088. [PMID: 32349372 PMCID: PMC7247714 DOI: 10.3390/ijms21093088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/18/2020] [Accepted: 04/23/2020] [Indexed: 11/15/2022] Open
Abstract
Introns exist not only in coding sequences (CDSs) but also in untranslated regions (UTRs) of a gene. Recent studies in animals and model plants such as Arabidopsis have revealed that the UTR-introns (UIs) are widely presented in most genomes and involved in regulation of gene expression or RNA stability. In the present study, we identified introns at both 5'UTRs (5UIs) and 3'UTRs (3UIs) of sweet orange genes, investigated their size and nucleotide distribution characteristics, and explored the distribution of cis-elements in the UI sequences. Functional category of genes with predicted UIs were further analyzed using GO, KEGG, and PageMan enrichment. In addition, the organ-dependent splicing and abundance of selected UI-containing genes in root, leaf, and stem were experimentally determined. Totally, we identified 825 UI- and 570 3UI-containing transcripts, corresponding to 617 and 469 genes, respectively. Among them, 74 genes contain both 5UI and 3UI. Nucleotide distribution analysis showed that 5UI distribution is biased at both ends of 5'UTR whiles 3UI distribution is biased close to the start site of 3'UTR. Cis- elements analysis revealed that 5UI and 3UI sequences were rich of promoter-enhancing related elements, indicating that they might function in regulating the expression through them. Function enrichment analysis revealed that genes containing 5UI are significantly enriched in the RNA transport pathway. While, genes containing 3UI are significantly enriched in splicesome. Notably, many pentatricopeptide repeat-containing protein genes and the disease resistance genes were identified to be 3UI-containing. RT-PCR result confirmed the existence of UIs in the eight selected gene transcripts whereas alternative splicing events were found in some of them. Meanwhile, qRT-PCR result showed that UIs were differentially expressed among organs, and significant correlation was found between some genes and their UIs, for example: The expression of VPS28 and its 3UI was significantly negative correlated. This is the first report about the UIs in sweet orange from genome-wide level, which could provide evidence for further understanding of the role of UIs in gene expression regulation.
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Affiliation(s)
- Xiaobao Shi
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Junwei Wu
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Raphael Anue Mensah
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Na Tian
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Jiapeng Liu
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Fan Liu
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Jialan Chen
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Jingru Che
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Ye Guo
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Binghua Wu
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Guangyan Zhong
- Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
| | - Chunzhen Cheng
- College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
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XPO5 promotes primary miRNA processing independently of RanGTP. Nat Commun 2020; 11:1845. [PMID: 32296071 PMCID: PMC7160132 DOI: 10.1038/s41467-020-15598-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 03/17/2020] [Indexed: 12/24/2022] Open
Abstract
XPO5 mediates nuclear export of miRNA precursors in a RanGTP-dependent manner. However, XPO5-associated RNA species have not been determined globally and it is unclear whether XPO5 has any additional functions other than nuclear export. Here we show XPO5 pervasively binds to double-stranded RNA regions found in some clustered primary miRNA precursors and many cellular RNAs. Surprisingly, the binding of XPO5 to pri-miRNAs such as mir-17~92 and mir-15b~16-2 and highly structured RNAs such as vault RNAs is RanGTP-independent. Importantly, XPO5 enhances the processing efficiency of pri-mir-19a and mir-15b~16-2 by the DROSHA/DGCR8 microprocessor. Genetic deletion of XPO5 compromises the biogenesis of most miRNAs and leads to severe defects during mouse embryonic development and skin morphogenesis. This study reveals an unexpected function of XPO5 for recognizing and facilitating the nuclear cleavage of clustered pri-miRNAs, identifies numerous cellular RNAs bound by XPO5, and demonstrates physiological functions of XPO5 in mouse development. XPO5 mediates nuclear export of miRNA hairpin precursors (pre-miRNAs) through a RanGTP-dependent binding. Here the authors employ HITS-CLIP and biochemical analysis and show that XPO5 binds and promotes nuclear processing of clustered pri-miRNAs, with extensive double-stranded regions, independently of RanGTP.
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Moore S, Rabichow BE, Sattler R. The Hitchhiker's Guide to Nucleocytoplasmic Trafficking in Neurodegeneration. Neurochem Res 2020; 45:1306-1327. [PMID: 32086712 DOI: 10.1007/s11064-020-02989-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 02/12/2020] [Accepted: 02/14/2020] [Indexed: 12/12/2022]
Abstract
The widespread nature of nucleocytoplasmic trafficking defects and protein accumulation suggests distinct yet overlapping mechanisms in a variety of neurodegenerative diseases. Detailed understanding of the cellular pathways involved in nucleocytoplasmic transport and its dysregulation are essential for elucidating neurodegenerative pathogenesis and pinpointing potential areas for therapeutic intervention. The transport of cargos from the nucleus to the cytoplasm is generally regulated by the structure and function of the nuclear pore as well as the karyopherin α/β, importin, exportin, and mRNA export mechanisms. The disruption of these crucial transport mechanisms has been extensively described in the context of neurodegenerative diseases. One common theme in neurodegeneration is the cytoplasmic aggregation of proteins, including nuclear RNA binding proteins, repeat expansion associated gene products, and tau. These cytoplasmic aggregations are partly a consequence of failed nucleocytoplasmic transport machinery, but can also further disrupt transport, creating cyclical feed-forward mechanisms that exacerbate neurodegeneration. Here we describe the canonical mechanisms that regulate nucleocytoplasmic trafficking as well as how these mechanisms falter in neurodegenerative diseases.
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Affiliation(s)
- Stephen Moore
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA.,School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Benjamin E Rabichow
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA
| | - Rita Sattler
- Department of Neurobiology, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA.
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Guo L, Mohd KS, Ren H, Xin G, Jiang Q, Clarke PR, Zhang C. Phosphorylation of importin-α1 by CDK1-cyclin B1 controls mitotic spindle assembly. J Cell Sci 2019; 132:jcs232314. [PMID: 31434716 PMCID: PMC6765185 DOI: 10.1242/jcs.232314] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/09/2019] [Indexed: 12/22/2022] Open
Abstract
Importin-α serves as an adaptor linking importin-β to proteins carrying a nuclear localization sequence (NLS). During interphase, this interaction enables nuclear protein import, while in mitosis it regulates spindle assembly factors (SAFs) and controls microtubule nucleation, stabilization and spindle function. Here, we show that human importin-α1 is regulated during the cell cycle and is phosphorylated at two sites (threonine 9 and serine 62) during mitosis by the major mitotic protein kinase CDK1-cyclin B. Mutational analysis indicates that the mitotic phosphorylation of importin-α1 inhibits its binding to importin-β and promotes the release of TPX2 and KIFC1, which are then targeted like importin-β to the spindle. Loss of importin-α1 or expression of a non-phosphorylated mutant of importin-α1 results in the formation of shortened spindles with reduced microtubule density and induces a prolonged metaphase, whereas phosphorylation-mimicking mutants are functional in mitosis. We propose that phosphorylation of importin-α1 is a general mechanism for the spatial and temporal control of mitotic spindle assembly by CDK1-cyclin B1 that acts through the release of SAFs such as TPX2 and KIFC1 from inhibitory complexes that restrict spindle assembly.
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Affiliation(s)
- Li Guo
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Khamsah Suryati Mohd
- School of Medicine, Jacqui Wood Cancer Centre, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
| | - He Ren
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Guangwei Xin
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Qing Jiang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
| | - Paul R Clarke
- School of Medicine, Jacqui Wood Cancer Centre, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, Brisbane, QLD 4102, Australia
| | - Chuanmao Zhang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, College of Life Sciences, Peking University, Beijing 100871, China
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Aksu M, Trakhanov S, Vera Rodriguez A, Görlich D. Structural basis for the nuclear import and export functions of the biportin Pdr6/Kap122. J Cell Biol 2019; 218:1839-1852. [PMID: 31023722 PMCID: PMC6548137 DOI: 10.1083/jcb.201812093] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/26/2019] [Accepted: 03/28/2019] [Indexed: 12/26/2022] Open
Abstract
Importins ferry proteins into nuclei while exportins carry cargoes to the cytoplasm. In the accompanying paper in this issue (Vera Rodriguez et al. 2019. J. Cell Biol. https://doi.org/10.1083/jcb.201812091), we discovered that Pdr6 is a biportin that imports, e.g., the SUMO E2 ligase Ubc9 while depleting the translation factor eIF5A from the nuclear compartment. In this paper, we report the structures of key transport intermediates, namely, of the Ubc9•Pdr6 import complex, of the RanGTP•Pdr6 heterodimer, and of the trimeric RanGTP•Pdr6•eIF5A export complex. These revealed nonlinear transport signals, chaperone-like interactions, and how the RanGTPase system drives Pdr6 to transport Ubc9 and eIF5A in opposite directions. The structures also provide unexpected insights into the evolution of transport selectivity. Specifically, they show that recognition of Ubc9 by Pdr6 differs fundamentally from that of the human Ubc9-importer Importin 13. Likewise, Pdr6 recognizes eIF5A in a nonhomologous manner compared with the mammalian eIF5A-exporter Exportin 4. This suggests that the import of Ubc9 and active nuclear exclusion of eIF5A evolved in different eukaryotic lineages more than once and independently from each other.
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Affiliation(s)
- Metin Aksu
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Sergei Trakhanov
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Arturo Vera Rodriguez
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Dirk Görlich
- Department of Cellular Logistics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
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Ferreira PA. The coming-of-age of nucleocytoplasmic transport in motor neuron disease and neurodegeneration. Cell Mol Life Sci 2019; 76:2247-2273. [PMID: 30742233 PMCID: PMC6531325 DOI: 10.1007/s00018-019-03029-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 01/28/2019] [Indexed: 12/11/2022]
Abstract
The nuclear pore is the gatekeeper of nucleocytoplasmic transport and signaling through which a vast flux of information is continuously exchanged between the nuclear and cytoplasmic compartments to maintain cellular homeostasis. A unifying and organizing principle has recently emerged that cements the notion that several forms of amyotrophic lateral sclerosis (ALS), and growing number of other neurodegenerative diseases, co-opt the dysregulation of nucleocytoplasmic transport and that this impairment is a pathogenic driver of neurodegeneration. The understanding of shared pathomechanisms that underpin neurodegenerative diseases with impairments in nucleocytoplasmic transport and how these interface with current concepts of nucleocytoplasmic transport is bound to illuminate this fundamental biological process in a yet more physiological context. Here, I summarize unresolved questions and evidence and extend basic and critical concepts and challenges of nucleocytoplasmic transport and its role in the pathogenesis of neurodegenerative diseases, such as ALS. These principles will help to appreciate the roles of nucleocytoplasmic transport in the pathogenesis of ALS and other neurodegenerative diseases, and generate a framework for new ideas of the susceptibility of motoneurons, and possibly other neurons, to degeneration by dysregulation of nucleocytoplasmic transport.
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Affiliation(s)
- Paulo A Ferreira
- Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA.
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50
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Jevtić P, Schibler AC, Wesley CC, Pegoraro G, Misteli T, Levy DL. The nucleoporin ELYS regulates nuclear size by controlling NPC number and nuclear import capacity. EMBO Rep 2019; 20:embr.201847283. [PMID: 31085625 DOI: 10.15252/embr.201847283] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 04/09/2019] [Accepted: 04/11/2019] [Indexed: 12/13/2022] Open
Abstract
How intracellular organelles acquire their characteristic sizes is a fundamental question in cell biology. Given stereotypical changes in nuclear size in cancer, it is important to understand the mechanisms that control nuclear size in human cells. Using a high-throughput imaging RNAi screen, we identify and mechanistically characterize ELYS, a nucleoporin required for post-mitotic nuclear pore complex (NPC) assembly, as a determinant of nuclear size in mammalian cells. ELYS knockdown results in small nuclei, reduced nuclear lamin B2 localization, lower NPC density, and decreased nuclear import. Increasing nuclear import by importin α overexpression rescues nuclear size and lamin B2 import, while inhibiting importin α/β-mediated nuclear import decreases nuclear size. Conversely, ELYS overexpression increases nuclear size, enriches nuclear lamin B2 at the nuclear periphery, and elevates NPC density and nuclear import. Consistent with these observations, knockdown or inhibition of exportin 1 increases nuclear size. Thus, we identify ELYS as a novel positive effector of mammalian nuclear size and propose that nuclear size is sensitive to NPC density and nuclear import capacity.
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Affiliation(s)
- Predrag Jevtić
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
| | | | - Chase C Wesley
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
| | - Gianluca Pegoraro
- High Throughput Imaging Facility (HiTIF), National Cancer Institute, NIH, Bethesda, MD, USA
| | - Tom Misteli
- National Cancer Institute, NIH, Bethesda, MD, USA
| | - Daniel L Levy
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
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