1
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Makeyev EV, Huang S. The perinucleolar compartment: structure, function, and utility in anti-cancer drug development. Nucleus 2024; 15:2306777. [PMID: 38281066 PMCID: PMC10824145 DOI: 10.1080/19491034.2024.2306777] [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: 09/25/2023] [Accepted: 01/12/2024] [Indexed: 01/29/2024] Open
Abstract
The perinucleolar compartment (PNC) was initially identified as a nuclear structure enriched for the polypyrimidine tract-binding protein. Since then, the PNC has been implicated in carcinogenesis. The prevalence of this compartment is positively correlated with disease progression in various types of cancer, and its expression in primary tumors is linked to worse patient outcomes. Using the PNC as a surrogate marker for anti-cancer drug efficacy has led to the development of a clinical candidate for anti-metastasis therapies. The PNC is a multicomponent nuclear body situated at the periphery of the nucleolus. Thus far, several non-coding RNAs and RNA-binding proteins have been identified as the PNC components. Here, we summarize the current understanding of the structure and function of the PNC, as well as its recurrent links to cancer progression and metastasis.
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Affiliation(s)
- Eugene V. Makeyev
- Centre for Developmental Neurobiology, King’s College London, London, UK
| | - Sui Huang
- Department of Cell and Developmental Biology, Northwestern University, Chicago, IL, USA
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2
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Chung TH, Zhuravskaya A, Makeyev EV. Regulation potential of transcribed simple repeated sequences in developing neurons. Hum Genet 2024; 143:875-895. [PMID: 38153590 PMCID: PMC11294396 DOI: 10.1007/s00439-023-02626-1] [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: 07/19/2023] [Accepted: 11/28/2023] [Indexed: 12/29/2023]
Abstract
Simple repeated sequences (SRSs), defined as tandem iterations of microsatellite- to satellite-sized DNA units, occupy a substantial part of the human genome. Some of these elements are known to be transcribed in the context of repeat expansion disorders. Mounting evidence suggests that the transcription of SRSs may also contribute to normal cellular functions. Here, we used genome-wide bioinformatics approaches to systematically examine SRS transcriptional activity in cells undergoing neuronal differentiation. We identified thousands of long noncoding RNAs containing >200-nucleotide-long SRSs (SRS-lncRNAs), with hundreds of these transcripts significantly upregulated in the neural lineage. We show that SRS-lncRNAs often originate from telomere-proximal regions and that they have a strong potential to form multivalent contacts with a wide range of RNA-binding proteins. Our analyses also uncovered a cluster of neurally upregulated SRS-lncRNAs encoded in a centromere-proximal part of chromosome 9, which underwent an evolutionarily recent segmental duplication. Using a newly established in vitro system for rapid neuronal differentiation of induced pluripotent stem cells, we demonstrate that at least some of the bioinformatically predicted SRS-lncRNAs, including those encoded in the segmentally duplicated part of chromosome 9, indeed increase their expression in developing neurons to readily detectable levels. These and other lines of evidence suggest that many SRSs may be expressed in a cell type and developmental stage-specific manner, providing a valuable resource for further studies focused on the functional consequences of SRS-lncRNAs in the normal development of the human brain, as well as in the context of neurodevelopmental disorders.
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Affiliation(s)
- Tek Hong Chung
- Centre for Developmental Neurobiology, New Hunt's House, King's College London, London, SE1 1UL, UK
| | - Anna Zhuravskaya
- Centre for Developmental Neurobiology, New Hunt's House, King's College London, London, SE1 1UL, UK
| | - Eugene V Makeyev
- Centre for Developmental Neurobiology, New Hunt's House, King's College London, London, SE1 1UL, UK.
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3
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Kumari A, Vertii A. Perspective: "Current understanding of NADs dynamics and mechanisms of Disease". Gene 2024; 894:147960. [PMID: 37923094 DOI: 10.1016/j.gene.2023.147960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 10/09/2023] [Accepted: 10/31/2023] [Indexed: 11/07/2023]
Abstract
Chromatin architecture is essential for gene regulation, and multiple levels of the 3D chromatin organization exhibit dynamic changes during organismal development and cell differentiation. Heterochromatin, termed compartment B in Hi-C datasets, is a phase-separating gene-silencing form of chromatin, preferentially located at the two nuclear sites, nuclear (lamina-associate chromatin domains, LADs) and nucleoli (nucleoli-associated chromatin domains, NADs) peripheries. LADs and NADs contain both interchangeable and location-specific chromatin domains. Recent studies suggest striking dynamics in LADs and NADs during the differentiation of embryonic stem cells into neural progenitors and neurons. Here we discuss recent advances in understanding NADs changes during neuronal differentiation and future questions on how NADs integrity can contribute to healthy neurodevelopment and neurodevelopment diseases.
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Affiliation(s)
- Amrita Kumari
- Department of Molecular, Cellular and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 1605, US
| | - Anastassiia Vertii
- Department of Molecular, Cellular and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 1605, US.
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4
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Hao Q, Liu M, Daulatabad SV, Gaffari S, Song YJ, Srivastava R, Bhaskar S, Moitra A, Mangan H, Tseng E, Gilmore RB, Frier SM, Chen X, Wang C, Huang S, Chamberlain S, Jin H, Korlach J, McStay B, Sinha S, Janga SC, Prasanth SG, Prasanth KV. Monoallelically expressed noncoding RNAs form nucleolar territories on NOR-containing chromosomes and regulate rRNA expression. eLife 2024; 13:e80684. [PMID: 38240312 PMCID: PMC10852677 DOI: 10.7554/elife.80684] [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: 05/31/2022] [Accepted: 01/18/2024] [Indexed: 02/07/2024] Open
Abstract
Out of the several hundred copies of rRNA genes arranged in the nucleolar organizing regions (NOR) of the five human acrocentric chromosomes, ~50% remain transcriptionally inactive. NOR-associated sequences and epigenetic modifications contribute to the differential expression of rRNAs. However, the mechanism(s) controlling the dosage of active versus inactive rRNA genes within each NOR in mammals is yet to be determined. We have discovered a family of ncRNAs, SNULs (Single NUcleolus Localized RNA), which form constrained sub-nucleolar territories on individual NORs and influence rRNA expression. Individual members of the SNULs monoallelically associate with specific NOR-containing chromosomes. SNULs share sequence similarity to pre-rRNA and localize in the sub-nucleolar compartment with pre-rRNA. Finally, SNULs control rRNA expression by influencing pre-rRNA sorting to the DFC compartment and pre-rRNA processing. Our study discovered a novel class of ncRNAs influencing rRNA expression by forming constrained nucleolar territories on individual NORs.
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Affiliation(s)
- Qinyu Hao
- Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Minxue Liu
- Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Swapna Vidhur Daulatabad
- Department of BioHealth Informatics, School of Informatics and Computing, IUPUIIndianapolisUnited States
| | - Saba Gaffari
- Department of Computer Science, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - You Jin Song
- Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Rajneesh Srivastava
- Department of BioHealth Informatics, School of Informatics and Computing, IUPUIIndianapolisUnited States
| | - Shivang Bhaskar
- Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Anurupa Moitra
- Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Hazel Mangan
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland GalwayGalwayIreland
| | | | - Rachel B Gilmore
- Department of Genetics and Genome Sciences, University of Connecticut School of MedicineFarmingtonUnited States
| | | | - Xin Chen
- Department of Biophysics and Quantitative Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Chengliang Wang
- Department of Biochemistry, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Sui Huang
- Department of Cell and Molecular Biology, Northwestern UniversityChicagoUnited States
| | - Stormy Chamberlain
- Department of Genetics and Genome Sciences, University of Connecticut School of MedicineFarmingtonUnited States
| | - Hong Jin
- Department of Biophysics and Quantitative Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
- Department of Biochemistry, University of Illinois at Urbana-ChampaignUrbanaUnited States
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | | | - Brian McStay
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland GalwayGalwayIreland
| | - Saurabh Sinha
- Department of Computer Science, University of Illinois at Urbana-ChampaignUrbanaUnited States
- Department of Biomedical Engineering, Georgia TechAtlantaUnited States
| | - Sarath Chandra Janga
- Department of BioHealth Informatics, School of Informatics and Computing, IUPUIIndianapolisUnited States
| | - Supriya G Prasanth
- Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
- Cancer Center at Illinois, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Kannanganattu V Prasanth
- Department of Cell and Developmental Biology, University of Illinois at Urbana-ChampaignUrbanaUnited States
- Cancer Center at Illinois, University of Illinois at Urbana-ChampaignUrbanaUnited States
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5
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Diaz LR, Gil-Ranedo J, Jaworek KJ, Nsek N, Marques JP, Costa E, Hilton DA, Bieluczyk H, Warrington O, Hanemann CO, Futschik ME, Bossing T, Barros CS. Ribogenesis boosts controlled by HEATR1-MYC interplay promote transition into brain tumour growth. EMBO Rep 2024; 25:168-197. [PMID: 38225354 PMCID: PMC10897169 DOI: 10.1038/s44319-023-00017-1] [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: 02/06/2023] [Revised: 11/16/2023] [Accepted: 11/22/2023] [Indexed: 01/17/2024] Open
Abstract
Cell commitment to tumourigenesis and the onset of uncontrolled growth are critical determinants in cancer development but the early events directing tumour initiating cell (TIC) fate remain unclear. We reveal a single-cell transcriptome profile of brain TICs transitioning into tumour growth using the brain tumour (brat) neural stem cell-based Drosophila model. Prominent changes in metabolic and proteostasis-associated processes including ribogenesis are identified. Increased ribogenesis is a known cell adaptation in established tumours. Here we propose that brain TICs boost ribogenesis prior to tumour growth. In brat-deficient TICs, we show that this dramatic change is mediated by upregulated HEAT-Repeat Containing 1 (HEATR1) to promote ribosomal RNA generation, TIC enlargement and onset of overgrowth. High HEATR1 expression correlates with poor glioma patient survival and patient-derived glioblastoma stem cells rely on HEATR1 for enhanced ribogenesis and tumourigenic potential. Finally, we show that HEATR1 binds the master growth regulator MYC, promotes its nucleolar localisation and appears required for MYC-driven ribogenesis, suggesting a mechanism co-opted in ribogenesis reprogramming during early brain TIC development.
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Affiliation(s)
- Laura R Diaz
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Jon Gil-Ranedo
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Karolina J Jaworek
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
- School of Biological Sciences, Bangor University, LL57 2UW, Bangor, UK
| | - Nsikan Nsek
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Joao Pinheiro Marques
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Eleni Costa
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - David A Hilton
- Department of Cellular and Anatomical Pathology, University Hospitals Plymouth, PL6 8DH, Plymouth, UK
| | - Hubert Bieluczyk
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Oliver Warrington
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
- Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, WC1N 3AR, London, UK
| | - C Oliver Hanemann
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Matthias E Futschik
- School of Biomedical Sciences, Faculty of Health, Derriford Research Facility, University of Plymouth, PL6 8BU, Plymouth, UK
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-504, Coimbra, Portugal
| | - Torsten Bossing
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK
| | - Claudia S Barros
- Peninsula Medical School, Faculty of Health, John Bull Building, University of Plymouth, PL6 8BU, Plymouth, UK.
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6
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van Bueren MAE, Janssen A. The impact of chromatin on double-strand break repair: Imaging tools and discoveries. DNA Repair (Amst) 2024; 133:103592. [PMID: 37976899 DOI: 10.1016/j.dnarep.2023.103592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 10/16/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
Eukaryotic nuclei are constantly being exposed to factors that break or chemically modify the DNA. Accurate repair of this DNA damage is crucial to prevent DNA mutations and maintain optimal cell function. To overcome the detrimental effects of DNA damage, a multitude of repair pathways has evolved. These pathways need to function properly within the different chromatin domains present in the nucleus. Each of these domains exhibit distinct molecular- and bio-physical characteristics that can influence the response to DNA damage. In particular, chromatin domains highly enriched for repetitive DNA sequences, such as nucleoli, centromeres and pericentromeric heterochromatin require tailored repair mechanisms to safeguard genome stability. Work from the past decades has led to the development of innovative imaging tools as well as inducible DNA damage techniques to gain new insights into the impact of these repetitive chromatin domains on the DNA repair process. Here we summarize these tools with a particular focus on Double-Strand Break (DSB) repair, and discuss the insights gained into our understanding of the influence of chromatin domains on DSB -dynamics and -repair pathway choice.
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Affiliation(s)
- Marit A E van Bueren
- Center for Molecular Medicine, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands
| | - Aniek Janssen
- Center for Molecular Medicine, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, the Netherlands.
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7
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Böğürcü-Seidel N, Ritschel N, Acker T, Németh A. Beyond ribosome biogenesis: noncoding nucleolar RNAs in physiology and tumor biology. Nucleus 2023; 14:2274655. [PMID: 37906621 PMCID: PMC10730139 DOI: 10.1080/19491034.2023.2274655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/19/2023] [Indexed: 11/02/2023] Open
Abstract
The nucleolus, the largest subcompartment of the nucleus, stands out from the nucleoplasm due to its exceptionally high local RNA and low DNA concentrations. Within this central hub of nuclear RNA metabolism, ribosome biogenesis is the most prominent ribonucleoprotein (RNP) biogenesis process, critically determining the structure and function of the nucleolus. However, recent studies have shed light on other roles of the nucleolus, exploring the interplay with various noncoding RNAs that are not directly involved in ribosome synthesis. This review focuses on this intriguing topic and summarizes the techniques to study and the latest findings on nucleolar long noncoding RNAs (lncRNAs) as well as microRNAs (miRNAs) in the context of nucleolus biology beyond ribosome biogenesis. We particularly focus on the multifaceted roles of the nucleolus and noncoding RNAs in physiology and tumor biology.
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Affiliation(s)
| | - Nadja Ritschel
- Institute of Neuropathology, Justus Liebig University Giessen, Giessen, Germany
| | - Till Acker
- Institute of Neuropathology, Justus Liebig University Giessen, Giessen, Germany
| | - Attila Németh
- Institute of Neuropathology, Justus Liebig University Giessen, Giessen, Germany
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8
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Wang C, Ma H, Baserga SJ, Pederson T, Huang S. Nucleolar structure connects with global nuclear organization. Mol Biol Cell 2023; 34:ar114. [PMID: 37610836 PMCID: PMC10846622 DOI: 10.1091/mbc.e23-02-0062] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 08/25/2023] Open
Abstract
The nucleolus is a multifunctional nuclear body. To tease out the roles of nucleolar structure without resorting to the use of multi-action drugs, we knocked down the RNA polymerase I subunit RPA194 in HeLa cells by siRNA. Loss of RPA194 resulted in nucleolar-structural segregation and effects on both nucleolus-proximal and distal-nuclear components. The perinucleolar compartment was disrupted, centromere clustering around nucleoli was significantly reduced, and the intranuclear locations of specific genomic loci were altered. Moreover, Cajal bodies, distal from nucleoli, underwent morphological and some compositional changes. In comparison, when the preribosomal RNA-processing factor, UTP4, was knocked down, neither nucleolar segregation nor the intranuclear effects were observed, demonstrating that the changes of nucleolar proximal and distal nuclear domains in RPA194 knockdown cells unlikely arise from a cessation of ribosome synthesis, rather from the consequence of nucleolar-structure alteration. These findings point to a commutative system that links nucleolar structure to the maintenance and spatial organization of certain nuclear domains and genomic loci.
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Affiliation(s)
- Chen Wang
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Hanhui Ma
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA 01605
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Susan J. Baserga
- Department of Genetics, Yale School of Medicine, New Haven, CT 06520
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520
| | - Thoru Pederson
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA 01605
| | - Sui Huang
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
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9
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Belli V, Maiello D, Di Lorenzo C, Furia M, Vicidomini R, Turano M. New Insights into Dyskerin-CypA Interaction: Implications for X-Linked Dyskeratosis Congenita and Beyond. Genes (Basel) 2023; 14:1766. [PMID: 37761906 PMCID: PMC10531313 DOI: 10.3390/genes14091766] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/27/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
The highly conserved family of cyclophilins comprises multifunctional chaperones that interact with proteins and RNAs, facilitating the dynamic assembly of multimolecular complexes involved in various cellular processes. Cyclophilin A (CypA), the predominant member of this family, exhibits peptidyl-prolyl cis-trans isomerase activity. This enzymatic function aids with the folding and activation of protein structures and often serves as a molecular regulatory switch for large multimolecular complexes, ensuring appropriate inter- and intra-molecular interactions. Here, we investigated the involvement of CypA in the nucleus, where it plays a crucial role in supporting the assembly and trafficking of heterogeneous ribonucleoproteins (RNPs). We reveal that CypA is enriched in the nucleolus, where it colocalizes with the pseudouridine synthase dyskerin, the catalytic component of the multifunctional H/ACA RNPs involved in the modification of cellular RNAs and telomere stability. We show that dyskerin, whose mutations cause the X-linked dyskeratosis (X-DC) and the Hoyeraal-Hreidarsson congenital ribosomopathies, can directly interact with CypA. These findings, together with the remark that substitution of four dyskerin prolines are known to cause X-DC pathogenic mutations, lead us to indicate this protein as a CypA client. The data presented here suggest that this chaperone can modulate dyskerin activity influencing all its partecipated RNPs.
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Affiliation(s)
- Valentina Belli
- Istituto Nazionale Tumori—IRCSS—Fondazione G. Pascale, 80131 Naples, Italy;
| | - Daniela Maiello
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (D.M.); (C.D.L.); (M.F.)
| | - Concetta Di Lorenzo
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (D.M.); (C.D.L.); (M.F.)
- Department of Advanced Medical and Surgical Sciences, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Maria Furia
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (D.M.); (C.D.L.); (M.F.)
| | - Rosario Vicidomini
- Section on Cellular Communication, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Mimmo Turano
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (D.M.); (C.D.L.); (M.F.)
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10
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Mitchell RJ, Kriger SM, Fenton AD, Havrylyuk D, Pandeya A, Sun Y, Smith T, DeRouchey JE, Unrine JM, Oza V, Blackburn JS, Wei Y, Heidary DK, Glazer EC. A monoadduct generating Ru(ii) complex induces ribosome biogenesis stress and is a molecular mimic of phenanthriplatin. RSC Chem Biol 2023; 4:344-353. [PMID: 37181632 PMCID: PMC10170627 DOI: 10.1039/d2cb00247g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Accepted: 02/01/2023] [Indexed: 03/03/2023] Open
Abstract
Ruthenium complexes are often investigated as potential replacements for platinum-based chemotherapeutics in hopes of identifying systems with improved tolerability in vivo and reduced susceptibility to cellular resistance mechanisms. Inspired by phenanthriplatin, a non-traditional platinum agent that contains only one labile ligand, monofunctional ruthenium polypyridyl agents have been developed, but until now, few demonstrated promising anticancer activity. Here we introduce a potent new scaffold, based on [Ru(tpy)(dip)Cl]Cl (tpy = 2,2':6',2''-terpyridine and dip = 4,7-diphenyl-1,10-phenanthroline) in pursuit of effective Ru(ii)-based monofunctional agents. Notably, the extension of the terpyridine at the 4' position with an aromatic ring resulted in a molecule that was cytotoxic in several cancer cell lines with sub-micromolar IC50 values, induced ribosome biogenesis stress, and exhibited minimal zebrafish embryo toxicity. This study demonstrates the successful design of a Ru(ii) agent that mimics many of the biological effects and phenotypes seen with phenanthriplatin, despite numerous differences in both the ligands and metal center structure.
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Affiliation(s)
- Richard J Mitchell
- Department of Chemistry, University of Kentucky 505 Rose St. Lexington KY 40506 USA
| | - Sarah M Kriger
- Department of Chemistry, North Carolina State University 2620 Yarbrough DriveRaleigh NC 27695 USA
| | - Alexander D Fenton
- Department of Chemistry, University of Kentucky 505 Rose St. Lexington KY 40506 USA
| | - Dmytro Havrylyuk
- Department of Chemistry, University of Kentucky 505 Rose St. Lexington KY 40506 USA
| | - Ankit Pandeya
- Department of Chemistry, University of Kentucky 505 Rose St. Lexington KY 40506 USA
| | - Yang Sun
- Department of Chemistry, University of Kentucky 505 Rose St. Lexington KY 40506 USA
| | - Tami Smith
- Department of Plant and Soil Sciences, University of Kentucky 1100 S. Limestone St Lexington KY 40546 USA
| | - Jason E DeRouchey
- Department of Chemistry, University of Kentucky 505 Rose St. Lexington KY 40506 USA
| | - Jason M Unrine
- Department of Plant and Soil Sciences, University of Kentucky 1100 S. Limestone St Lexington KY 40546 USA
| | - Viral Oza
- Department of Molecular and Cellular Biochemistry, University of Kentucky 741 S. Limestone St. Lexington KY 40536 USA
| | - Jessica S Blackburn
- Department of Molecular and Cellular Biochemistry, University of Kentucky 741 S. Limestone St. Lexington KY 40536 USA
| | - Yinan Wei
- Department of Chemistry, University of Kentucky 505 Rose St. Lexington KY 40506 USA
| | - David K Heidary
- Department of Chemistry, North Carolina State University 2620 Yarbrough DriveRaleigh NC 27695 USA
| | - Edith C Glazer
- Department of Chemistry, North Carolina State University 2620 Yarbrough DriveRaleigh NC 27695 USA
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11
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Wang C, Ma H, Baserga SJ, Pederson T, Huang S. Nucleolar structure connects with global nuclear organization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.30.534966. [PMID: 37034708 PMCID: PMC10081344 DOI: 10.1101/2023.03.30.534966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The nucleolus is a multi-functional nuclear body. To tease out the roles of nucleolar structure without resorting to multi-action drugs, we knocked down RNA polymerase I subunit RPA194 in HeLa cells by siRNA. Loss of RPA194 resulted in nucleolar structural segregation and effects on both nucleolus-proximal and distal nuclear components. The perinucleolar compartment was disrupted, centromere-nucleolus interactions were significantly reduced, and the intranuclear locations of specific genomic loci were altered. Moreover, Cajal bodies, distal from nucleoli, underwent morphological and compositional changes. To distinguish whether these global reorganizations are the results of nucleolar structural disruption or inhibition of ribosome synthesis, the pre-ribosomal RNA processing factor, UTP4, was also knocked down, which did not lead to nucleolar segregation, nor the intranuclear effects seen with RPA195A knockdown, demonstrating that they do not arise from a cessation of ribosome synthesis. These findings point to a commutative system that links nucleolar structure to the maintenance and spatial organization of certain nuclear bodies and genomic loci.
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Affiliation(s)
- Chen Wang
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Hanhui Ma
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA
- School of Life Science and Technology, Shanghai Tech University, Shanghai, China
| | - Susan J Baserga
- Department of Genetics, Yale School of Medicine, New Haven, CT
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT
- Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT
| | - Thoru Pederson
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA
| | - Sui Huang
- Department of Cell and Developmental Biology, Northwestern University Feinberg School of Medicine, Chicago, IL
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12
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Ni C, Buszczak M. The homeostatic regulation of ribosome biogenesis. Semin Cell Dev Biol 2023; 136:13-26. [PMID: 35440410 PMCID: PMC9569395 DOI: 10.1016/j.semcdb.2022.03.043] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 12/22/2022]
Abstract
The continued integrity of biological systems depends on a balance between interdependent elements at the molecular, cellular, and organismal levels. This is particularly true for the generation of ribosomes, which influence almost every aspect of cell and organismal biology. Ribosome biogenesis (RiBi) is an energetically demanding process that involves all three RNA polymerases, numerous RNA processing factors, chaperones, and the coordinated expression of 79-80 ribosomal proteins (r-proteins). Work over the last several decades has revealed that the dynamic regulation of ribosome production represents a major mechanism by which cells maintain homeostasis in response to changing environmental conditions and acute stress. More recent studies suggest that cells and tissues within multicellular organisms exhibit dramatically different levels of ribosome production and protein synthesis, marked by the differential expression of RiBi factors. Thus, distinct bottlenecks in the RiBi process, downstream of rRNA transcription, may exist within different cell populations of multicellular organisms during development and in adulthood. This review will focus on our current understanding of the mechanisms that link the complex molecular process of ribosome biogenesis with cellular and organismal physiology. We will discuss diverse topics including how different steps in the RiBi process are coordinated with one another, how MYC and mTOR impact RiBi, and how RiBi levels change between stem cells and their differentiated progeny. In turn, we will also review how regulated changes in ribosome production itself can feedback to influence cell fate and function.
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Affiliation(s)
- Chunyang Ni
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Michael Buszczak
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA.
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13
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Romanowska-Duda Z, Piotrowski K, Stępiński D, Popłońska K. A Promising Ash Supplementation Strategy in the Cultivation of Spirodela polyrrhiza Plants. Cells 2023; 12:289. [PMID: 36672224 PMCID: PMC9856745 DOI: 10.3390/cells12020289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/05/2023] [Accepted: 01/09/2023] [Indexed: 01/15/2023] Open
Abstract
An innovative approach to the management of waste in the form of ash obtained during biomass combustion is justified due to its specific properties, including the presence of macro- and microelements. The aim of the current study was to determine the concentration of ash obtained from Sorghum combustion regarding its fertilizer value and its effect on the cytological structures, physiological parameters, growth and development of Lemnaceae plants, thereby demonstrating the possibility of using this waste to supplement culture media. The analyses showed that the use of ash in the in vitro cultivation of Lemnaceae aquatic plants had a dose-dependent effect. The addition of 2% ash favorably affected the condition of plant roots, i.e., meristem elongation and an increase in nucleoli sizes as well as improving the chlorophyll content index, gas exchange parameters, chemical oxygen demand (COD) and plant vigor via PSII, which was confirmed by a chlorophyll fluorescence measurement. On the other hand, too high of a concentration, i.e., 10% ash, adversely affected the plant development and parameters studied. Concluding, the use of ash at a low concentration favorably affected the yielding of Spirodela polyrrhiza, whose biomass can be used for energy purposes in the production of bioethanol, plant biogas or the phytoremediation of industrial waters and leachate.
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Affiliation(s)
- Zdzisława Romanowska-Duda
- Department of Plant Ecophysiology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 92-237 Lodz, Poland
| | - Krzysztof Piotrowski
- Department of Plant Ecophysiology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 92-237 Lodz, Poland
| | - Dariusz Stępiński
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| | - Katarzyna Popłońska
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
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14
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Fu Y, Liu Y, Wen T, Fang J, Chen Y, Zhou Z, Gu X, Wu H, Sheng J, Xu Z, Zou W, Chen B. Real-time imaging of RNA polymerase I activity in living human cells. J Biophys Biochem Cytol 2022; 222:213608. [PMID: 36282216 PMCID: PMC9606689 DOI: 10.1083/jcb.202202110] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 08/19/2022] [Accepted: 09/27/2022] [Indexed: 11/22/2022] Open
Abstract
RNA polymerase I (Pol I) synthesizes about 60% of cellular RNA by transcribing multiple copies of the ribosomal RNA gene (rDNA). The transcriptional activity of Pol I controls the level of ribosome biogenesis and cell growth. However, there is currently a lack of methods for monitoring Pol I activity in real time. Here, we develop LiveArt (live imaging-based analysis of rDNA transcription) to visualize and quantify the spatiotemporal dynamics of endogenous ribosomal RNA (rRNA) synthesis. LiveArt reveals mitotic silencing and reactivation of rDNA transcription, as well as the transcriptional kinetics of interphase rDNA. Using LiveArt, we identify SRFBP1 as a potential regulator of rRNA synthesis. We show that rDNA transcription occurs in bursts and can be altered by modulating burst duration and amplitude. Importantly, LiveArt is highly effective in the screening application for anticancer drugs targeting Pol I transcription. These approaches pave the way for a deeper understanding of the mechanisms underlying nucleolar functions.
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Affiliation(s)
- Yujuan Fu
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China
| | - Yaxin Liu
- Institute of Environmental Medicine, and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Tanye Wen
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jie Fang
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China
| | - Yalong Chen
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ziying Zhou
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xinyi Gu
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hao Wu
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jinghao Sheng
- Institute of Environmental Medicine, and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhengping Xu
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China,Institute of Environmental Medicine, and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Wei Zou
- The Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, China,Insititute of Translational Medicine, Zhejiang University, Hangzhou, China,Wei Zou:
| | - Baohui Chen
- Department of Cell Biology and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China,Institute of Hematology, Zhejiang University and Zhejiang Engineering Laboratory for Stem Cell and Immunotherapy, Hangzhou, China,Zhejiang Provincial Key Laboratory of Genetic & Developmental Disorders, Hangzhou, China,Correspondence to Baohui Chen:
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15
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van Schaik T, Manzo SG, Vouzas AE, Liu NQ, Teunissen H, de Wit E, Gilbert DM, van Steensel B. Dynamic chromosomal interactions and control of heterochromatin positioning by Ki-67. EMBO Rep 2022; 23:e55782. [PMID: 36245428 PMCID: PMC9724667 DOI: 10.15252/embr.202255782] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 09/26/2022] [Accepted: 09/29/2022] [Indexed: 11/05/2022] Open
Abstract
Ki-67 is a chromatin-associated protein with a dynamic distribution pattern throughout the cell cycle and is thought to be involved in chromatin organization. The lack of genomic interaction maps has hampered a detailed understanding of its roles, particularly during interphase. By pA-DamID mapping in human cell lines, we find that Ki-67 associates with large genomic domains that overlap mostly with late-replicating regions. Early in interphase, when Ki-67 is present in pre-nucleolar bodies, it interacts with these domains on all chromosomes. However, later in interphase, when Ki-67 is confined to nucleoli, it shows a striking shift toward small chromosomes. Nucleolar perturbations indicate that these cell cycle dynamics correspond to nucleolar maturation during interphase, and suggest that nucleolar sequestration of Ki-67 limits its interactions with larger chromosomes. Furthermore, we demonstrate that Ki-67 does not detectably control chromatin-chromatin interactions during interphase, but it competes with the nuclear lamina for interaction with late-replicating DNA, and it controls replication timing of (peri)centromeric regions. Together, these results reveal a highly dynamic choreography of genome interactions and roles for Ki-67 in heterochromatin organization.
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Affiliation(s)
- Tom van Schaik
- Division of Gene Regulation and Oncode InstituteNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - Stefano G Manzo
- Division of Gene Regulation and Oncode InstituteNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - Athanasios E Vouzas
- Department of Biological ScienceThe Florida State UniversityTallahasseeFLUSA,San Diego Biomedical Research InstituteSan DiegoCAUSA
| | - Ning Qing Liu
- Division of Gene Regulation and Oncode InstituteNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - Hans Teunissen
- Division of Gene Regulation and Oncode InstituteNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - Elzo de Wit
- Division of Gene Regulation and Oncode InstituteNetherlands Cancer InstituteAmsterdamThe Netherlands
| | - David M Gilbert
- Department of Biological ScienceThe Florida State UniversityTallahasseeFLUSA,San Diego Biomedical Research InstituteSan DiegoCAUSA
| | - Bas van Steensel
- Division of Gene Regulation and Oncode InstituteNetherlands Cancer InstituteAmsterdamThe Netherlands,Department of Cell BiologyErasmus University Medical CentreRotterdamThe Netherlands
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16
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Nucleolus and Nucleolar Stress: From Cell Fate Decision to Disease Development. Cells 2022; 11:cells11193017. [PMID: 36230979 PMCID: PMC9563748 DOI: 10.3390/cells11193017] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/19/2022] [Accepted: 09/22/2022] [Indexed: 11/30/2022] Open
Abstract
Besides the canonical function in ribosome biogenesis, there have been significant recent advances towards the fascinating roles of the nucleolus in stress response, cell destiny decision and disease progression. Nucleolar stress, an emerging concept describing aberrant nucleolar structure and function as a result of impaired rRNA synthesis and ribosome biogenesis under stress conditions, has been linked to a variety of signaling transductions, including but not limited to Mdm2-p53, NF-κB and HIF-1α pathways. Studies have uncovered that nucleolus is a stress sensor and signaling hub when cells encounter various stress conditions, such as nutrient deprivation, DNA damage and oxidative and thermal stress. Consequently, nucleolar stress plays a pivotal role in the determination of cell fate, such as apoptosis, senescence, autophagy and differentiation, in response to stress-induced damage. Nucleolar homeostasis has been involved in the pathogenesis of various chronic diseases, particularly tumorigenesis, neurodegenerative diseases and metabolic disorders. Mechanistic insights have revealed the indispensable role of nucleolus-initiated signaling in the progression of these diseases. Accordingly, the intervention of nucleolar stress may pave the path for developing novel therapies against these diseases. In this review, we systemically summarize recent findings linking the nucleolus to stress responses, signaling transduction and cell-fate decision, set the spotlight on the mechanisms by which nucleolar stress drives disease progression, and highlight the merit of the intervening nucleolus in disease treatment.
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17
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Lytic Reactivation of the Kaposi’s Sarcoma-Associated Herpesvirus (KSHV) Is Accompanied by Major Nucleolar Alterations. Viruses 2022; 14:v14081720. [PMID: 36016343 PMCID: PMC9412354 DOI: 10.3390/v14081720] [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: 06/14/2022] [Revised: 07/21/2022] [Accepted: 07/28/2022] [Indexed: 02/01/2023] Open
Abstract
The nucleolus is a subnuclear compartment whose primary function is the biogenesis of ribosomal subunits. Certain viral infections affect the morphology and composition of the nucleolar compartment and influence ribosomal RNA (rRNA) transcription and maturation. However, no description of nucleolar morphology and function during infection with Kaposi’s sarcoma-associated herpesvirus (KSHV) is available to date. Using immunofluorescence microscopy, we documented extensive destruction of the nuclear and nucleolar architecture during the lytic reactivation of KSHV. This was manifested by the redistribution of key nucleolar proteins, including the rRNA transcription factor UBF. Distinct delocalization patterns were evident; certain nucleolar proteins remained together whereas others dissociated, implying that nucleolar proteins undergo nonrandom programmed dispersion. Significantly, the redistribution of UBF was dependent on viral DNA replication or late viral gene expression. No significant changes in pre-rRNA levels and no accumulation of pre-rRNA intermediates were found by RT-qPCR and Northern blot analysis. Furthermore, fluorescent in situ hybridization (FISH), combined with immunofluorescence, revealed an overlap between Fibrillarin and internal transcribed spacer 1 (ITS1), which represents the primary product of the pre-rRNA, suggesting that the processing of rRNA proceeds during lytic reactivation. Finally, small changes in the levels of pseudouridylation (Ψ) and 2′-O-methylation (Nm) were documented across the rRNA; however, none were localized to the functional domain. Taken together, our results suggest that despite dramatic changes in the nucleolar organization, rRNA transcription and processing persist during lytic reactivation of KSHV. Whether the observed nucleolar alterations favor productive infection or signify cellular anti-viral responses remains to be determined.
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18
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Transcription Dependent Loss of an Ectopically Expressed Variant Surface Glycoprotein during Antigenic Variation in Trypanosoma brucei. mBio 2022; 13:e0384721. [PMID: 35229632 PMCID: PMC8941856 DOI: 10.1128/mbio.03847-21] [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] [Indexed: 12/13/2022] Open
Abstract
In the mammalian host, Trypanosoma brucei is coated in a single-variant surface glycoprotein (VSG) species. Stochastic switching of the expressed VSG allows the parasite to escape detection by the host immune system. DNA double-strand breaks (DSB) trigger VSG switching, and repair via gene conversion results in an antigenically distinct VSG being expressed from the single active bloodstream-form expression site (BES). The single active BES is marked by VSG exclusion 2 (VEX2) protein. Here, we have disrupted monoallelic VSG expression by stably expressing a second telomeric VSG from a ribosomal locus. We found that cells expressing two VSGs contained one VEX2 focus that was significantly larger in size than the wild-type cells; this therefore suggests the ectopic VSG is expressed from the same nuclear position as the active BES. Unexpectedly, we report that in the double VSG-expressing cells, the DNA sequence of the ectopic copy is lost following a DSB in the active BES, despite it being spatially separated in the genome. The loss of the ectopic VSG is dependent on active transcription and does not disrupt the number or variety of templates used to repair a BES DSB and elicit a VSG switch. We propose that there are stringent mechanisms within the cell to reinforce monoallelic expression during antigenic variation. IMPORTANCE The single-cell parasite Trypanosoma brucei causes the fatal disease human African trypanosomiasis and is able to colonize the blood, fat, skin, and central nervous system. Trypanosomes survive in the mammalian host owing to a dense protective protein coat that consists of a single-variant surface glycoprotein species. Stochastic switching of one VSG for an immunologically distinct one enables the parasite to escape recognition by the host immune system. We have disrupted monoallelic antigen expression by expressing a second VSG and report that following DSB-triggered VSG switching, the DNA sequence of the ectopic VSG is lost in a transcription-dependent manner. We propose that there are strict requirements to ensure that only one variant antigen is expressed following a VSG switch, which has important implications for understanding how the parasite survives in the mammalian host.
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19
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Abstract
In eukaryotic cells, protein and RNA factors involved in genome activities like transcription, RNA processing, DNA replication, and repair accumulate in self-organizing membraneless chromatin subcompartments. These structures contribute to efficiently conduct chromatin-mediated reactions and to establish specific cellular programs. However, the underlying mechanisms for their formation are only partly understood. Recent studies invoke liquid-liquid phase separation (LLPS) of proteins and RNAs in the establishment of chromatin activity patterns. At the same time, the folding of chromatin in the nucleus can drive genome partitioning into spatially distinct domains. Here, the interplay between chromatin organization, chromatin binding, and LLPS is discussed by comparing and contrasting three prototypical chromatin subcompartments: the nucleolus, clusters of active RNA polymerase II, and pericentric heterochromatin domains. It is discussed how the different ways of chromatin compartmentalization are linked to transcription regulation, the targeting of soluble factors to certain parts of the genome, and to disease-causing genetic aberrations.
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Affiliation(s)
- Karsten Rippe
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, 69120 Heidelberg, Germany
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20
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9-Aminoacridine Inhibits Ribosome Biogenesis by Targeting Both Transcription and Processing of Ribosomal RNA. Int J Mol Sci 2022; 23:ijms23031260. [PMID: 35163183 PMCID: PMC8836032 DOI: 10.3390/ijms23031260] [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: 12/10/2021] [Revised: 01/18/2022] [Accepted: 01/19/2022] [Indexed: 12/13/2022] Open
Abstract
Aminoacridines, used for decades as antiseptic and antiparasitic agents, are prospective candidates for therapeutic repurposing and new drug development. Although the mechanisms behind their biological effects are not fully elucidated, they are most often attributed to the acridines’ ability to intercalate into DNA. Here, we characterized the effects of 9-aminoacridine (9AA) on pre-rRNA metabolism in cultured mammalian cells. Our results demonstrate that 9AA inhibits both transcription of the ribosomal RNA precursors (pre-rRNA) and processing of the already synthesized pre-rRNAs, thereby rapidly abolishing ribosome biogenesis. Using a fluorescent intercalator displacement assay, we further show that 9AA can bind to RNA in vitro, which likely contributes to its ability to inhibit post-transcriptional steps in pre-rRNA maturation. These findings extend the arsenal of small-molecule compounds that can be used to block ribosome biogenesis in mammalian cells and have implications for the pharmacological development of new ribosome biogenesis inhibitors.
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21
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Wu M, Lu L, Chen S, Li Y, Zhang Q, Fu S, Deng X. Natural products inducing nucleolar stress: implications in cancer therapy. Anticancer Drugs 2022; 33:e21-e27. [PMID: 34561998 DOI: 10.1097/cad.0000000000001146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The nucleolus is the site of ribosome biogenesis and is found to play an important role in stress sensing. For over 100 years, the increase in the size and number of nucleoli has been considered as a marker of aggressive tumors. Despite this, the contribution of the nucleolus and the biologic processes mediated by it to cancer pathogenesis has been largely overlooked. This state has been changed over the recent decades with the demonstration that the nucleolus controls numerous cellular functions associated with cancer development. Induction of nucleolar stress has recently been regarded as being superior to conventional cytotoxic/cytostatic strategy in that it is more selective to neoplastic cells while sparing normal cells. Natural products represent an excellent source of bioactive molecules and some of them have been found to be able to induce nucleolar stress. The demonstration of these nucleolar stress-inducing natural products has paved the way for a new therapeutic approach to more delicate tumor cell-killing. This review provides a contemporary summary of the role of the nucleolus as a novel promising target for cancer therapy, with particular emphasis on natural products as an exciting new class of anti-cancer drugs with nucleolar stress-inducing properties.
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Affiliation(s)
- Mi Wu
- Key Laboratory of Translational Cancer Stem Cell Research, Hunan Normal University
- Department of Pathophysiology, Hunan Normal University School of Medicine, Changsha
| | - Lu Lu
- Key Laboratory of Translational Cancer Stem Cell Research, Hunan Normal University
- Department of Pathophysiology, Hunan Normal University School of Medicine, Changsha
| | - Sisi Chen
- Key Laboratory of Translational Cancer Stem Cell Research, Hunan Normal University
- Department of Pathophysiology, Hunan Normal University School of Medicine, Changsha
| | - Ying Li
- Key Laboratory of Translational Cancer Stem Cell Research, Hunan Normal University
- Department of Pathophysiology, Hunan Normal University School of Medicine, Changsha
| | - Qiuting Zhang
- Key Laboratory of Translational Cancer Stem Cell Research, Hunan Normal University
- Department of Pathophysiology, Hunan Normal University School of Medicine, Changsha
| | - Shujun Fu
- Key Laboratory of Translational Cancer Stem Cell Research, Hunan Normal University
- Department of Pathophysiology, Hunan Normal University School of Medicine, Changsha
| | - Xiyun Deng
- Key Laboratory of Translational Cancer Stem Cell Research, Hunan Normal University
- Department of Pathophysiology, Hunan Normal University School of Medicine, Changsha
- Department of Pathophysiology, Jishou University School of Medicine, Jishou, Hunan, China
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22
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Otellin VA, Khozhai LI, Shishko TT, Vershinina EA. Nucleolar Ultrastructure in Neurons of the Rat Neocortical Sensorimotor Area during the Neonatal Period after Perinatal Hypoxic Exposure and Its Pharmacological Correction. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s0022093021060053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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23
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Kim Y, Kim TK, Shin Y, Tak E, Song GW, Oh YM, Kim JK, Pack CG. Characterizing Organelles in Live Stem Cells Using Label-Free Optical Diffraction Tomography. Mol Cells 2021; 44:851-860. [PMID: 34819398 PMCID: PMC8627838 DOI: 10.14348/molcells.2021.0190] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/27/2021] [Accepted: 09/09/2021] [Indexed: 01/10/2023] Open
Abstract
Label-free optical diffraction tomography (ODT), an imaging technology that does not require fluorescent labeling or other pre-processing, can overcome the limitations of conventional cell imaging technologies, such as fluorescence and electron microscopy. In this study, we used ODT to characterize the cellular organelles of three different stem cells-namely, human liver derived stem cell, human umbilical cord matrix derived mesenchymal stem cell, and human induced pluripotent stem cell-based on their refractive index and volume of organelles. The physical property of each stem cell was compared with that of fibroblast. Based on our findings, the characteristic physical properties of specific stem cells can be quantitatively distinguished based on their refractive index and volume of cellular organelles. Altogether, the method employed herein could aid in the distinction of living stem cells from normal cells without the use of fluorescence or specific biomarkers.
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Affiliation(s)
- Youngkyu Kim
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea
| | - Tae-Keun Kim
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea
| | - Yeonhee Shin
- Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Eunyoung Tak
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea
- Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Gi-Won Song
- Division of Hepatobiliary Surgery and Liver Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Yeon-Mok Oh
- Department of Pulmonary and Critical Care Medicine, Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Jun Ki Kim
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea
- Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Chan-Gi Pack
- Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea
- Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea
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24
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Zhu Y, Cheng C, Chen L, Zhang L, Pan H, Hou L, Sun Z, Zhang L, Fu X, Chan KY, Zhang J. Cell cycle heterogeneity directs spontaneous 2C state entry and exit in mouse embryonic stem cells. Stem Cell Reports 2021; 16:2659-2673. [PMID: 34624246 PMCID: PMC8580870 DOI: 10.1016/j.stemcr.2021.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 09/07/2021] [Accepted: 09/08/2021] [Indexed: 12/01/2022] Open
Abstract
Mouse embryonic stem cells (ESCs) show cell-to-cell heterogeneity. A small number of two-cell-like cells (2CLCs) marked by endogenous retrovirus activation emerge spontaneously. The 2CLCs are unstable and they are prone to transiting back to the pluripotent state without extrinsic stimulus. To understand how this bidirectional transition takes place, we performed single-cell RNA sequencing on isolated 2CLCs that underwent 2C-like state exit and re-entry, and revealed a step-by-step transitional process between 2C-like and pluripotent states. Mechanistically, we found that cell cycle played an important role in mediating these transitions by regulating assembly of the nucleolus and peri-nucleolar heterochromatin to influence 2C gene Dux expression. Collectively, our findings provide a roadmap of the 2C-like state entry and exit in ESCs and also a causal role of the cell cycle in promoting these transitions. The entry to and exit from the 2C-like state showed a step-by-step roadmap Cell cycle participates in mediating dynamic transitions between ESCs and 2CLCs G1/S phase arrest facilitates the Dux locus escape from heterochromatin Nucleolus-heterochromatin remodeling is involved in 2C activation
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Affiliation(s)
- Yuqing Zhu
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China; Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Haining, Zhejiang, China
| | - Chen Cheng
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China
| | - Lang Chen
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China
| | - Li Zhang
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China
| | - Hongru Pan
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China
| | - Linxiao Hou
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China
| | - Zhen Sun
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China
| | - Ling Zhang
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China; Zhejiang Laboratory for Systems and Precision Medicine, Zhejiang University Medical Center, Hangzhou, Zhejiang, China
| | - Xudong Fu
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China; Zhejiang Laboratory for Systems and Precision Medicine, Zhejiang University Medical Center, Hangzhou, Zhejiang, China; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kuan Yoow Chan
- Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Haining, Zhejiang, China
| | - Jin Zhang
- Center for Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Hangzhou, Zhejiang, China; Zhejiang Laboratory for Systems and Precision Medicine, Zhejiang University Medical Center, Hangzhou, Zhejiang, China; Institute of Hematology, Zhejiang University, Hangzhou, Zhejiang, China; Center of Gene/Cell Engineering and Genome Medicine, Hangzhou, Zhejiang, China.
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25
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Yap K, Chung TH, Makeyev EV. Hybridization-proximity labeling reveals spatially ordered interactions of nuclear RNA compartments. Mol Cell 2021; 82:463-478.e11. [PMID: 34741808 PMCID: PMC8791277 DOI: 10.1016/j.molcel.2021.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 10/11/2021] [Accepted: 10/12/2021] [Indexed: 12/11/2022]
Abstract
The ability of RNAs to form specific contacts with other macromolecules provides an important mechanism for subcellular compartmentalization. Here we describe a suite of hybridization-proximity (HyPro) labeling technologies for unbiased discovery of proteins (HyPro-MS) and transcripts (HyPro-seq) associated with RNAs of interest in genetically unperturbed cells. As a proof of principle, we show that HyPro-MS and HyPro-seq can identify both known and previously unexplored spatial neighbors of the noncoding RNAs 45S, NEAT1, and PNCTR expressed at markedly different levels. Notably, HyPro-seq uncovers an extensive repertoire of incompletely processed, adenosine-to-inosine-edited transcripts accumulating at the interface between their encoding chromosomal regions and the NEAT1-containing paraspeckle compartment. At least some of these targets require NEAT1 for their optimal expression. Overall, this study provides a versatile toolkit for dissecting RNA interactomes in diverse biomedical contexts and expands our understanding of the functional architecture of the mammalian nucleus. HyPro labeling uncovers interactors and spatial neighbors of RNAs of interest Protein and RNA partners are identified by mass spectrometry and deep sequencing No genetic modifications are required, allowing wider biomedical use Interactomes of RNA-containing nuclear bodies are mapped as a proof of principle
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Affiliation(s)
- Karen Yap
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
| | - Tek Hong Chung
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
| | - Eugene V Makeyev
- Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK.
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26
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Miyake T, McDermott JC. Nucleolar localization of c-Jun. FEBS J 2021; 289:748-765. [PMID: 34499807 DOI: 10.1111/febs.16187] [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] [Received: 07/21/2021] [Revised: 08/09/2021] [Accepted: 09/06/2021] [Indexed: 01/20/2023]
Abstract
Nucleoli are well defined for their function in ribosome biogenesis, but only a small fraction of the nucleolar proteome has been characterized. Here, we report that the proto-oncogene, c-Jun, is targeted to the nucleolus. Using live cell imaging in myogenic cells, we document that the c-Jun basic domain contains a unique, evolutionarily conserved motif that determines nucleolar targeting. Fos family Jun dimer partners, such as Fra2, while nuclear, do not co-localize with c-Jun in the nucleolus. A point mutation in c-Jun that mimics Fra2 (M260E) in its Nucleolar Localization sequence (NoLS) results in loss of c-Jun nucleolar targeting while still preserving nuclear localization. Fra2 can sequester c-Jun in the nucleoplasm, indicating that the stoichiometric ratio of heterodimeric partners regulates c-Jun nucleolar targeting. Finally, nucleolar localization of c-Jun modulates nucleolar architecture and ribosomal RNA accumulation. These studies highlight a novel role for Jun family proteins in the nucleolus, having potential implications for a diverse array of AP-1-regulated cellular processes.
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Affiliation(s)
- Tetsuaki Miyake
- Department of Biology, York University, Toronto, ON, Canada.,Muscle Health Research Centre (MHRC), York University, Toronto, ON, Canada.,Centre for Research in Biomolecular Interactions (CRBI), York University, Toronto, ON, Canada
| | - John C McDermott
- Department of Biology, York University, Toronto, ON, Canada.,Muscle Health Research Centre (MHRC), York University, Toronto, ON, Canada.,Centre for Research in Biomolecular Interactions (CRBI), York University, Toronto, ON, Canada.,Centre for Research in Mass Spectrometry (CRMS), York University, Toronto, ON, Canada
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27
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Thoms HC, Stark LA. The NF-κB Nucleolar Stress Response Pathway. Biomedicines 2021; 9:biomedicines9091082. [PMID: 34572268 PMCID: PMC8471347 DOI: 10.3390/biomedicines9091082] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/09/2021] [Accepted: 08/20/2021] [Indexed: 12/20/2022] Open
Abstract
The nuclear organelle, the nucleolus, plays a critical role in stress response and the regulation of cellular homeostasis. P53 as a downstream effector of nucleolar stress is well defined. However, new data suggests that NF-κB also acts downstream of nucleolar stress to regulate cell growth and death. In this review, we will provide insight into the NF-κB nucleolar stress response pathway. We will discuss apoptosis mediated by nucleolar sequestration of RelA and new data demonstrating a role for p62 (sequestosome (SQSTM1)) in this process. We will also discuss activation of NF-κB signalling by degradation of the RNA polymerase I (PolI) complex component, transcription initiation factor-IA (TIF-IA (RRN3)), and contexts where TIF-IA-NF-κB signalling may be important. Finally, we will discuss how this pathway is targeted by aspirin to mediate apoptosis of colon cancer cells.
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28
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Rodríguez-Fernández L, Company S, Zaragozá R, Viña JR, García-Trevijano ER. Cleavage and activation of LIM kinase 1 as a novel mechanism for calpain 2-mediated regulation of nuclear dynamics. Sci Rep 2021; 11:16339. [PMID: 34381117 PMCID: PMC8358030 DOI: 10.1038/s41598-021-95797-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 07/30/2021] [Indexed: 12/26/2022] Open
Abstract
Calpain-2 (CAPN2) is a processing enzyme ubiquitously expressed in mammalian tissues whose pleiotropic functions depend on the role played by its cleaved-products. Nuclear interaction networks, crucial for a number of molecular processes, could be modified by CAPN2 activity. However, CAPN2 functions in cell nucleus are poorly understood. To unveil CAPN2 functions in this compartment, the result of CAPN2-mediated interactions in cell nuclei was studied in breast cancer cell (BCC) lines. CAPN2 abundance was found to be determinant for its nucleolar localization during interphase. Those CAPN2-dependent components of nucleolar proteome, including the actin-severing protein cofilin-1 (CFL1), were identified by proteomic approaches. CAPN2 binding, cleavage and activation of LIM Kinase-1 (LIMK1), followed by CFL1 phosphorylation was studied. Upon CAPN2-depletion, full-length LIMK1 levels increased and CFL1/LIMK1 binding was inhibited. In addition, LIMK1 accumulated at the cell periphery and perinucleolar region and, the mitosis-specific increase of CFL1 phosphorylation and localization was altered, leading to aberrant mitosis and cell multinucleation. These findings uncover a mechanism for the role of CAPN2 during mitosis, unveil the critical role of CAPN2 in the interactions among nuclear components and, identifying LIMK1 as a new CAPN2-target, provide a novel mechanism for LIMK1 activation. CFL1 is crucial for cytoskeleton remodeling and mitosis, but also for the maintenance of nuclear structure, the movement of chromosomes and the modulation of transcription frequently altered in cancer cells. Consequently, the role of CAPN2 in the nuclear compartment might be extended to other actin-associated biological and pathological processes.
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Affiliation(s)
- L Rodríguez-Fernández
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valencia, Avda. Blasco Ibañez, 15, 46010, Valencia, Spain
| | - S Company
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valencia, Avda. Blasco Ibañez, 15, 46010, Valencia, Spain
| | - R Zaragozá
- Fundación Investigación Hospital Clínico-INCLIVA, Valencia, Spain.,Departamento de Anatomía y Embriología Humana, Facultad de Medicina, Universidad de Valencia, Valencia, Spain
| | - J R Viña
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valencia, Avda. Blasco Ibañez, 15, 46010, Valencia, Spain.,Fundación Investigación Hospital Clínico-INCLIVA, Valencia, Spain
| | - E R García-Trevijano
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valencia, Avda. Blasco Ibañez, 15, 46010, Valencia, Spain. .,Fundación Investigación Hospital Clínico-INCLIVA, Valencia, Spain.
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29
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Yoneda M, Nakagawa T, Hattori N, Ito T. The nucleolus from a liquid droplet perspective. J Biochem 2021; 170:153-162. [PMID: 34358306 DOI: 10.1093/jb/mvab090] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 07/27/2021] [Indexed: 11/14/2022] Open
Abstract
The nucleolus is a membrane-less organelle sequestered from the nucleus by liquid droplet formation through a liquid-liquid phase separation (LLPS). It plays important roles in cell homeostasis through its internal thermodynamic changes. Reversible nucleolar transitions between coalescence and dispersion are dependent on the concentrations, conformations, and interactions of its molecular liquid droplet-forming components, including DNA, RNA, and protein. The liquid droplet-like properties of the nucleolus enable its diverse dynamic roles. The liquid droplet formation mechanism, by which the nucleolus is sequestered from the nucleoplasm despite the absence of a membrane, explains a number of complex nucleolar functions.
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Affiliation(s)
- Mitsuhiro Yoneda
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
| | - Takeya Nakagawa
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
| | - Naoko Hattori
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
| | - Takashi Ito
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
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30
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Abstract
Biomolecular condensates concentrate molecules to facilitate basic biochemical processes, including transcription and DNA replication. While liquid-like condensates have been ascribed various functions, solid-like condensates are generally thought of as amorphous sites of protein storage. Here, we show that solid-like amyloid bodies coordinate local nuclear protein synthesis (LNPS) during stress. On stimulus, translationally active ribosomes accumulate along fiber-like assemblies that characterize amyloid bodies. Mass spectrometry analysis identified regulatory ribosomal proteins and translation factors that relocalize from the cytoplasm to amyloid bodies to sustain LNPS. These amyloidogenic compartments are enriched in newly transcribed messenger RNA by Heat Shock Factor 1 (HSF1). Depletion of stress-induced ribosomal intergenic spacer noncoding RNA (rIGSRNA) that constructs amyloid bodies prevents recruitment of the nuclear protein synthesis machinery, abolishes LNPS, and impairs the nuclear HSF1 response. We propose that amyloid bodies support local nuclear translation during stress and that solid-like condensates can facilitate complex biochemical reactions as their liquid counterparts can.
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31
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Iarovaia OV, Ioudinkova ES, Velichko AK, Razin SV. Manipulation of Cellular Processes via Nucleolus Hijaking in the Course of Viral Infection in Mammals. Cells 2021; 10:cells10071597. [PMID: 34202380 PMCID: PMC8303250 DOI: 10.3390/cells10071597] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 12/16/2022] Open
Abstract
Due to their exceptional simplicity of organization, viruses rely on the resources, molecular mechanisms, macromolecular complexes, regulatory pathways, and functional compartments of the host cell for an effective infection process. The nucleolus plays an important role in the process of interaction between the virus and the infected cell. The interactions of viral proteins and nucleic acids with the nucleolus during the infection process are universal phenomena and have been described for almost all taxonomic groups. During infection, proteins of the nucleolus in association with viral components can be directly used for the processes of replication and transcription of viral nucleic acids and the assembly and transport of viral particles. In the course of a viral infection, the usurpation of the nucleolus functions occurs and the usurpation is accompanied by profound changes in ribosome biogenesis. Recent studies have demonstrated that the nucleolus is a multifunctional and dynamic compartment. In addition to the biogenesis of ribosomes, it is involved in regulating the cell cycle and apoptosis, responding to cellular stress, repairing DNA, and transcribing RNA polymerase II-dependent genes. A viral infection can be accompanied by targeted transport of viral proteins to the nucleolus, massive release of resident proteins of the nucleolus into the nucleoplasm and cytoplasm, the movement of non-nucleolar proteins into the nucleolar compartment, and the temporary localization of viral nucleic acids in the nucleolus. The interaction of viral and nucleolar proteins interferes with canonical and non-canonical functions of the nucleolus and results in a change in the physiology of the host cell: cell cycle arrest, intensification or arrest of ribosome biogenesis, induction or inhibition of apoptosis, and the modification of signaling cascades involved in the stress response. The nucleolus is, therefore, an important target during viral infection. In this review, we discuss the functional impact of viral proteins and nucleic acid interaction with the nucleolus during infection.
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32
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Davies C, Ooi CP, Sioutas G, Hall BS, Sidhu H, Butter F, Alsford S, Wickstead B, Rudenko G. TbSAP is a novel chromatin protein repressing metacyclic variant surface glycoprotein expression sites in bloodstream form Trypanosoma brucei. Nucleic Acids Res 2021; 49:3242-3262. [PMID: 33660774 PMCID: PMC8034637 DOI: 10.1093/nar/gkab109] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 02/02/2021] [Accepted: 02/11/2021] [Indexed: 12/13/2022] Open
Abstract
The African trypanosome Trypanosoma brucei is a unicellular eukaryote, which relies on a protective variant surface glycoprotein (VSG) coat for survival in the mammalian host. A single trypanosome has >2000 VSG genes and pseudogenes of which only one is expressed from one of ∼15 telomeric bloodstream form expression sites (BESs). Infectious metacyclic trypanosomes present within the tsetse fly vector also express VSG from a separate set of telomeric metacyclic ESs (MESs). All MESs are silenced in bloodstream form T. brucei. As very little is known about how this is mediated, we performed a whole genome RNAi library screen to identify MES repressors. This allowed us to identify a novel SAP domain containing DNA binding protein which we called TbSAP. TbSAP is enriched at the nuclear periphery and binds both MESs and BESs. Knockdown of TbSAP in bloodstream form trypanosomes did not result in cells becoming more ‘metacyclic-like'. Instead, there was extensive global upregulation of transcripts including MES VSGs, VSGs within the silent VSG arrays as well as genes immediately downstream of BES promoters. TbSAP therefore appears to be a novel chromatin protein playing an important role in silencing the extensive VSG repertoire of bloodstream form T. brucei.
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Affiliation(s)
- Carys Davies
- Sir Alexander Fleming Building, Department of Life Sciences, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - Cher-Pheng Ooi
- Sir Alexander Fleming Building, Department of Life Sciences, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - Georgios Sioutas
- Sir Alexander Fleming Building, Department of Life Sciences, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - Belinda S Hall
- Sir Alexander Fleming Building, Department of Life Sciences, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - Haneesh Sidhu
- Sir Alexander Fleming Building, Department of Life Sciences, Imperial College London, South Kensington, London SW7 2AZ, UK
| | - Falk Butter
- Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany
| | - Sam Alsford
- London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Bill Wickstead
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Gloria Rudenko
- Sir Alexander Fleming Building, Department of Life Sciences, Imperial College London, South Kensington, London SW7 2AZ, UK
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33
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Smolka JA, Sanz LA, Hartono SR, Chédin F. Recognition of RNA by the S9.6 antibody creates pervasive artifacts when imaging RNA:DNA hybrids. J Cell Biol 2021; 220:211957. [PMID: 33830170 PMCID: PMC8040515 DOI: 10.1083/jcb.202004079] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 02/01/2021] [Accepted: 03/10/2021] [Indexed: 12/11/2022] Open
Abstract
The S9.6 antibody is broadly used to detect RNA:DNA hybrids but has significant affinity for double-stranded RNA. The impact of this off-target RNA binding activity has not been thoroughly investigated, especially in the context of immunofluorescence microscopy. We report that S9.6 immunofluorescence signal observed in fixed human cells arises predominantly from ribosomal RNA, not RNA:DNA hybrids. S9.6 staining was unchanged by pretreatment with the RNA:DNA hybrid–specific nuclease RNase H1, despite verification in situ that S9.6 recognized RNA:DNA hybrids and that RNase H1 was active. S9.6 staining was, however, significantly sensitive to RNase T1, which specifically degrades RNA. Additional imaging and biochemical data indicate that the prominent cytoplasmic and nucleolar S9.6 signal primarily derives from ribosomal RNA. Importantly, genome-wide maps obtained by DNA sequencing after S9.6-mediated DNA:RNA immunoprecipitation (DRIP) are RNase H1 sensitive and RNase T1 insensitive. Altogether, these data demonstrate that imaging using S9.6 is subject to pervasive artifacts without pretreatments and controls that mitigate its promiscuous recognition of cellular RNAs.
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Affiliation(s)
- John A Smolka
- Department of Molecular and Cellular Biology and Genome Center, University of California, Davis, Davis, CA
| | - Lionel A Sanz
- Department of Molecular and Cellular Biology and Genome Center, University of California, Davis, Davis, CA
| | - Stella R Hartono
- Department of Molecular and Cellular Biology and Genome Center, University of California, Davis, Davis, CA
| | - Frédéric Chédin
- Department of Molecular and Cellular Biology and Genome Center, University of California, Davis, Davis, CA
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34
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MicroRNAs and long non-coding RNAs as novel regulators of ribosome biogenesis. Biochem Soc Trans 2021; 48:595-612. [PMID: 32267487 PMCID: PMC7200637 DOI: 10.1042/bst20190854] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/12/2020] [Accepted: 03/16/2020] [Indexed: 12/14/2022]
Abstract
Ribosome biogenesis is the fine-tuned, essential process that generates mature ribosomal subunits and ultimately enables all protein synthesis within a cell. Novel regulators of ribosome biogenesis continue to be discovered in higher eukaryotes. While many known regulatory factors are proteins or small nucleolar ribonucleoproteins, microRNAs (miRNAs), and long non-coding RNAs (lncRNAs) are emerging as a novel modulatory layer controlling ribosome production. Here, we summarize work uncovering non-coding RNAs (ncRNAs) as novel regulators of ribosome biogenesis and highlight their links to diseases of defective ribosome biogenesis. It is still unclear how many miRNAs or lncRNAs are involved in phenotypic or pathological disease outcomes caused by impaired ribosome production, as in the ribosomopathies, or by increased ribosome production, as in cancer. In time, we hypothesize that many more ncRNA regulators of ribosome biogenesis will be discovered, which will be followed by an effort to establish connections between disease pathologies and the molecular mechanisms of this additional layer of ribosome biogenesis control.
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35
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Taniue K, Akimitsu N. Aberrant phase separation and cancer. FEBS J 2021; 289:17-39. [PMID: 33583140 DOI: 10.1111/febs.15765] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/24/2021] [Accepted: 02/12/2021] [Indexed: 01/10/2023]
Abstract
Eukaryotic cells are intracellularly divided into numerous compartments or organelles, which coordinate specific molecules and biological reactions. Membrane-bound organelles are physically separated by lipid bilayers from the surrounding environment. Biomolecular condensates, also referred to membraneless organelles, are micron-scale cellular compartments that lack membranous enclosures but function to concentrate proteins and RNA molecules, and these are involved in diverse processes. Liquid-liquid phase separation (LLPS) driven by multivalent weak macromolecular interactions is a critical principle for the formation of biomolecular condensates, and a multitude of combinations among multivalent interactions may drive liquid-liquid phase transition (LLPT). Dysregulation of LLPS and LLPT leads to aberrant condensate and amyloid formation, which causes many human diseases, including neurodegeneration and cancer. Here, we describe recent findings regarding abnormal forms of biomolecular condensates and aggregation via aberrant LLPS and LLPT of cancer-related proteins in cancer development driven by mutation and fusion of genes. Moreover, we discuss the regulatory mechanisms by which aberrant LLPS and LLPT occur in cancer and the drug candidates targeting these mechanisms. Further understanding of the molecular events regulating how biomolecular condensates and aggregation form in cancer tissue is critical for the development of therapeutic strategies against tumorigenesis.
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Affiliation(s)
- Kenzui Taniue
- Isotope Science Center, The University of Tokyo, Japan.,Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, Japan
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36
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Smirnov E, Chmúrčiaková N, Liška F, Bažantová P, Cmarko D. Variability of Human rDNA. Cells 2021; 10:cells10020196. [PMID: 33498263 PMCID: PMC7909238 DOI: 10.3390/cells10020196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 12/15/2022] Open
Abstract
In human cells, ribosomal DNA (rDNA) is arranged in ten clusters of multiple tandem repeats. Each repeat is usually described as consisting of two parts: the 13 kb long ribosomal part, containing three genes coding for 18S, 5.8S and 28S RNAs of the ribosomal particles, and the 30 kb long intergenic spacer (IGS). However, this standard scheme is, amazingly, often altered as a result of the peculiar instability of the locus, so that the sequence of each repeat and the number of the repeats in each cluster are highly variable. In the present review, we discuss the causes and types of human rDNA instability, the methods of its detection, its distribution within the locus, the ways in which it is prevented or reversed, and its biological significance. The data of the literature suggest that the variability of the rDNA is not only a potential cause of pathology, but also an important, though still poorly understood, aspect of the normal cell physiology.
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37
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Houston R, Sekine S, Calderon MJ, Seifuddin F, Wang G, Kawagishi H, Malide DA, Li Y, Gucek M, Pirooznia M, Nelson AJ, Stokes MP, Stewart-Ornstein J, Mullett SJ, Wendell SG, Watkins SC, Finkel T, Sekine Y. Acetylation-mediated remodeling of the nucleolus regulates cellular acetyl-CoA responses. PLoS Biol 2020; 18:e3000981. [PMID: 33253182 PMCID: PMC7728262 DOI: 10.1371/journal.pbio.3000981] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 12/10/2020] [Accepted: 10/29/2020] [Indexed: 12/14/2022] Open
Abstract
The metabolite acetyl-coenzyme A (acetyl-CoA) serves as an essential element for a wide range of cellular functions including adenosine triphosphate (ATP) production, lipid synthesis, and protein acetylation. Intracellular acetyl-CoA concentrations are associated with nutrient availability, but the mechanisms by which a cell responds to fluctuations in acetyl-CoA levels remain elusive. Here, we generate a cell system to selectively manipulate the nucleo-cytoplasmic levels of acetyl-CoA using clustered regularly interspaced short palindromic repeat (CRISPR)-mediated gene editing and acetate supplementation of the culture media. Using this system and quantitative omics analyses, we demonstrate that acetyl-CoA depletion alters the integrity of the nucleolus, impairing ribosomal RNA synthesis and evoking the ribosomal protein-dependent activation of p53. This nucleolar remodeling appears to be mediated through the class IIa histone deacetylases (HDACs). Our findings highlight acetylation-mediated control of the nucleolus as an important hub linking acetyl-CoA fluctuations to cellular stress responses.
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Affiliation(s)
- Ryan Houston
- Aging Institute, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Shiori Sekine
- Aging Institute, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Division of Cardiology, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Michael J. Calderon
- Department of Cell Biology, Center for Biologic Imaging, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Fayaz Seifuddin
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Guanghui Wang
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Hiroyuki Kawagishi
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Daniela A. Malide
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Yuesheng Li
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Marjan Gucek
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Mehdi Pirooznia
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Alissa J. Nelson
- Cell Signaling Technology, INC., Danvers, Massachusetts, United States of America
| | - Matthew P. Stokes
- Cell Signaling Technology, INC., Danvers, Massachusetts, United States of America
| | - Jacob Stewart-Ornstein
- Department of Computational and Systems Biology, University of Pittsburgh and Hillman Cancer Center, Pittsburgh, Pennsylvania, United States of America
| | - Steven J. Mullett
- Department of Pharmacology and Chemical Biology, the Health Sciences Metabolomics and Lipidomics Core, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Stacy G. Wendell
- Department of Pharmacology and Chemical Biology, the Health Sciences Metabolomics and Lipidomics Core, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Simon C. Watkins
- Department of Cell Biology, Center for Biologic Imaging, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Toren Finkel
- Aging Institute, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Division of Cardiology, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
| | - Yusuke Sekine
- Aging Institute, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, United States of America
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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38
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Corvaisier M, Alvarado-Kristensson M. Non-Canonical Functions of the Gamma-Tubulin Meshwork in the Regulation of the Nuclear Architecture. Cancers (Basel) 2020; 12:cancers12113102. [PMID: 33114224 PMCID: PMC7690915 DOI: 10.3390/cancers12113102] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/17/2020] [Accepted: 10/21/2020] [Indexed: 12/15/2022] Open
Abstract
Simple Summary The appearance of a cell is connected to its function. For example, the fusiform of smooth muscle cells is adapted to facilitate muscle contraction, the lobed nucleus in white blood cells assists with the migratory behavior of these immune cells, and the condensed nucleus in sperm aids in their swimming efficiency. Thus, changes in appearance have been used for decades by doctors as a diagnostic method for human cancers. Here, we summarize our knowledge of how a cell maintains the shape of the nuclear compartment. Specifically, we discuss the role of a novel protein meshwork, the gamma-tubulin meshwork, in the regulation of nuclear morphology and as a therapeutic target against cancer. Abstract The nuclear architecture describes the organization of the various compartments in the nucleus of eukaryotic cells, where a plethora of processes such as nucleocytoplasmic transport, gene expression, and assembly of ribosomal subunits occur in a dynamic manner. During the different phases of the cell cycle, in post-mitotic cells and after oncogenic transformation, rearrangements of the nuclear architecture take place, and, among other things, these alterations result in reorganization of the chromatin and changes in gene expression. A member of the tubulin family, γtubulin, was first identified as part of a multiprotein complex that allows nucleation of microtubules. However, more than a decade ago, γtubulin was also characterized as a nuclear protein that modulates several crucial processes that affect the architecture of the nucleus. This review presents the latest knowledge regarding changes that arise in the nuclear architecture of healthy cells and under pathological conditions and, more specifically, considers the particular involvement of γtubulin in the modulation of the biology of the nuclear compartment.
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Báez-Becerra CT, Valencia-Rincón E, Velásquez-Méndez K, Ramírez-Suárez NJ, Guevara C, Sandoval-Hernandez A, Arboleda-Bustos CE, Olivos-Cisneros L, Gutiérrez-Ospina G, Arboleda H, Arboleda G. Nucleolar disruption, activation of P53 and premature senescence in POLR3A-mutated Wiedemann-Rautenstrauch syndrome fibroblasts. Mech Ageing Dev 2020; 192:111360. [PMID: 32976914 DOI: 10.1016/j.mad.2020.111360] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 09/15/2020] [Accepted: 09/17/2020] [Indexed: 01/01/2023]
Abstract
Recently, mutations in the RNA polymerase III subunit A (POLR3A) have been described as the cause of the neonatal progeria or Wiedemann-Rautenstrauch syndrome (WRS). POLR3A has important roles in transcription regulation of small RNAs, including tRNA, 5S rRNA, and 7SK rRNA. We aim to describe the cellular and molecular features of WRS fibroblasts. Cultures of primary fibroblasts from one WRS patient [monoallelic POLR3A variant c.3772_3773delCT (p.Leu1258Glyfs*12)] and one control patient were cultured in vitro. The mutation caused a decrease in the expression of wildtype POLR3A mRNA and POLR3A protein and a sharp increase in mutant protein expression. In addition, there was an increase in the nuclear localization of the mutant protein. These changes were associated with an increase in the number and area of nucleoli and to a high increase in the expression of pP53 and pH2AX. All these changes were associated with premature senescence. The present observations add to our understanding of the differences between Hutchinson-Gilford progeria syndrome and WRS and opens new alternatives to study cell senesce and human aging.
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Affiliation(s)
- Cindy Tatiana Báez-Becerra
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Estefania Valencia-Rincón
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Karen Velásquez-Méndez
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Nelson J Ramírez-Suárez
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Claudia Guevara
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Adrian Sandoval-Hernandez
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia; Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Carlos E Arboleda-Bustos
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Leonora Olivos-Cisneros
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de Mexico, Mexico
| | - Gabriel Gutiérrez-Ospina
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de Mexico, Mexico
| | - Humberto Arboleda
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia; Departamento de Pediatría, Facultad de Medicina, Universidad Nacional de Colombia Bogotá, Colombia
| | - Gonzalo Arboleda
- Grupo de Neurociencias y Muerte Celular, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia; Departamento de Patología, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia.
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Sharkey LM, Sandoval-Pistorius SS, Moore SJ, Gerson JE, Komlo R, Fischer S, Negron-Rios KY, Crowley EV, Padron F, Patel R, Murphy GG, Paulson HL. Modeling UBQLN2-mediated neurodegenerative disease in mice: Shared and divergent properties of wild type and mutant UBQLN2 in phase separation, subcellular localization, altered proteostasis pathways, and selective cytotoxicity. Neurobiol Dis 2020; 143:105016. [PMID: 32653673 DOI: 10.1016/j.nbd.2020.105016] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/26/2020] [Accepted: 07/07/2020] [Indexed: 12/12/2022] Open
Abstract
The ubiquitin-binding proteasomal shuttle protein UBQLN2 is implicated in common neurodegenerative disorders due to its accumulation in disease-specific aggregates and, when mutated, directly causes familial frontotemporal dementia/amyotrophic lateral sclerosis (FTD/ALS). Like other proteins linked to FTD/ALS, UBQLN2 undergoes phase separation to form condensates. The relationship of UBQLN2 phase separation and accumulation to neurodegeneration, however, remains uncertain. Employing biochemical, neuropathological and behavioral assays, we studied the impact of overexpressing WT or mutant UBQLN2 in the CNS of transgenic mice. Expression of UBQLN2 harboring a pathogenic mutation (P506T) elicited profound and widespread intraneuronal inclusion formation and aggregation without prominent neurodegenerative or behavioral changes. Both WT and mutant UBQLN2 formed ubiquitin- and P62-positive inclusions in neurons, supporting the view that UBQLN2 is intrinsically prone to phase separate, with the size, shape and frequency of inclusions depending on expression level and the presence or absence of a pathogenic mutation. Overexpression of WT or mutant UBQLN2 resulted in a dose-dependent decrease in levels of a key interacting chaperone, HSP70, as well as dose-dependent profound degeneration of the retina. We conclude that, at least in mice, robust aggregation of a pathogenic form of UBQLN2 is insufficient to cause neuronal loss recapitulating that of human FTD/ALS. Our results nevertheless support the view that altering the normal cellular balance of UBQLN2, whether wild type or mutant protein, has deleterious effects on cells of the CNS and retina that likely reflect perturbations in ubiquitin-dependent protein homeostasis.
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Affiliation(s)
- Lisa M Sharkey
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America.
| | - Stephanie S Sandoval-Pistorius
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, United States of America
| | - Shannon J Moore
- Michigan Neuroscience Institute and Department of Physiology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Julia E Gerson
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Robert Komlo
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Svetlana Fischer
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Keyshla Y Negron-Rios
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Emily V Crowley
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Francisco Padron
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Ronak Patel
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Geoffrey G Murphy
- Michigan Neuroscience Institute and Department of Physiology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America
| | - Henry L Paulson
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, United States of America.
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Engbrecht M, Mangerich A. The Nucleolus and PARP1 in Cancer Biology. Cancers (Basel) 2020; 12:cancers12071813. [PMID: 32640701 PMCID: PMC7408768 DOI: 10.3390/cancers12071813] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 06/26/2020] [Accepted: 07/01/2020] [Indexed: 12/13/2022] Open
Abstract
The nucleolus has been known for a long time to fulfill crucial functions in ribosome biogenesis, of which cancer cells can become addicted to in order to produce sufficient amounts of proteins for cell proliferation. Recently, the nucleolus has emerged as a central regulatory hub in many other cancer-relevant processes, including stress sensing, DNA damage response, cell cycle control, and proteostasis. This fostered the idea that nucleolar processes can be exploited in cancer therapy. Interestingly, a significant proportion of poly(ADP-ribose) polymerase 1 (PARP1) molecules are localized in the nucleolus and PARP1 also plays crucial roles in many processes that are important in cancer biology, including genome maintenance, replication, transcription, and chromatin remodeling. Furthermore, during the last years, PARP1 came into focus in oncology since it represents a promising target of pharmacological PARP inhibitors in various types of cancers. Here, we provide an overview of our current understanding on the role of PARP1 in nucleolar functions and discuss potential implications in cancer biology and therapy.
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Frank L, Rippe K. Repetitive RNAs as Regulators of Chromatin-Associated Subcompartment Formation by Phase Separation. J Mol Biol 2020; 432:4270-4286. [DOI: 10.1016/j.jmb.2020.04.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 04/14/2020] [Accepted: 04/14/2020] [Indexed: 12/21/2022]
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Picart-Picolo A, Picart C, Picault N, Pontvianne F. Nucleolus-associated chromatin domains are maintained under heat stress, despite nucleolar reorganization in Arabidopsis thaliana. JOURNAL OF PLANT RESEARCH 2020; 133:463-470. [PMID: 32372397 DOI: 10.1007/s10265-020-01201-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 04/17/2020] [Indexed: 05/23/2023]
Abstract
Several layers of mechanisms participate in plant adaptation to heat-stress. For example, the plant metabolism switches from cell growth mode to stress adaptation mode. Ribosome biogenesis is one of the most energy costly pathways. That biogenesis process occurs in the nucleolus, the largest nuclear compartment, whose structure is highly dependent on this pathway. We used a nucleolar marker to track the structure of the nucleolus, and revealed a change in its sub-nucleolar distribution under heat stress. In addition, the nucleolus is implicated in other cellular processes, such as genome organization within the nucleus. However, our analyses of nucleolus-associated chromatin domains under heat stress did not reveal significant differences compared to the control plants, suggesting a lack of connection between two of the main functions of the nucleolus: ribosome biogenesis and nuclear organization.
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Affiliation(s)
- Ariadna Picart-Picolo
- CNRS, LGDP UMR5096, Université de Perpignan, Perpignan, France
- UPVD, LGDP UMR5096, Université de Perpignan, Perpignan, France
| | - Claire Picart
- CNRS, LGDP UMR5096, Université de Perpignan, Perpignan, France
- UPVD, LGDP UMR5096, Université de Perpignan, Perpignan, France
| | - Nathalie Picault
- CNRS, LGDP UMR5096, Université de Perpignan, Perpignan, France
- UPVD, LGDP UMR5096, Université de Perpignan, Perpignan, France
| | - Frederic Pontvianne
- CNRS, LGDP UMR5096, Université de Perpignan, Perpignan, France.
- UPVD, LGDP UMR5096, Université de Perpignan, Perpignan, France.
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Cervantes M, Forné I, Ranjit S, Gratton E, Imhof A, Sassone-Corsi P. BMAL1 Associates with NOP58 in the Nucleolus and Contributes to Pre-rRNA Processing. iScience 2020; 23:101151. [PMID: 32450515 PMCID: PMC7256328 DOI: 10.1016/j.isci.2020.101151] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/30/2020] [Accepted: 05/05/2020] [Indexed: 12/24/2022] Open
Abstract
The transcription factor BMAL1 is a core element of the circadian clock that contributes to cyclic control of genes transcribed by RNA polymerase II. By using biochemical cellular fractionation and immunofluorescence analyses we reveal a previously uncharacterized nucleolar localization for BMAL1. We used an unbiased approach to determine the BMAL1 interactome by mass spectrometry and identified NOP58 as a prominent nucleolar interactor. NOP58, a core component of the box C/D small nucleolar ribonucleoprotein complex, associates with Snord118 to control specific pre-ribosomal RNA (pre-rRNA) processing steps. These results suggest a non-canonical role of BMAL1 in ribosomal RNA regulation. Indeed, we show that BMAL1 controls NOP58-associated Snord118 nucleolar levels and cleavage of unique pre-rRNA intermediates. Our findings identify an unsuspected function of BMAL1 in the nucleolus that appears distinct from its canonical role in the circadian clock system. BMAL1 displays a circadian-independent localization in the nucleolus Bmal1-deficient cells show altered nucleolar morphology Interactome proteomics reveals that BMAL1 associates with nucleolar proteins BMAL1 appears to play a non-canonical, non-circadian role in pre-rRNA processing
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Affiliation(s)
- Marlene Cervantes
- Center for Epigenetics and Metabolism, U1233 INSERM, Department of Biological Chemistry, University of California, Irvine, Irvine, CA 92697, USA
| | - Ignasi Forné
- Protein Analysis Unit, Biomedical Center, Ludwig Maximilian University of Munich, Munich 80539, Germany
| | - Suman Ranjit
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, Irvine, CA 92697, USA
| | - Enrico Gratton
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, Irvine, CA 92697, USA
| | - Axel Imhof
- Protein Analysis Unit, Biomedical Center, Ludwig Maximilian University of Munich, Munich 80539, Germany
| | - Paolo Sassone-Corsi
- Center for Epigenetics and Metabolism, U1233 INSERM, Department of Biological Chemistry, University of California, Irvine, Irvine, CA 92697, USA.
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Maiser A, Dillinger S, Längst G, Schermelleh L, Leonhardt H, Németh A. Super-resolution in situ analysis of active ribosomal DNA chromatin organization in the nucleolus. Sci Rep 2020; 10:7462. [PMID: 32366902 PMCID: PMC7198602 DOI: 10.1038/s41598-020-64589-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 04/01/2020] [Indexed: 12/21/2022] Open
Abstract
Ribosomal RNA (rRNA) transcription by RNA polymerase I (Pol I) is the first key step of ribosome biogenesis. While the molecular mechanisms of rRNA transcription regulation have been elucidated in great detail, the functional organization of the multicopy rRNA gene clusters (rDNA) in the nucleolus is less well understood. Here we apply super-resolution 3D structured illumination microscopy (3D-SIM) to investigate the spatial organization of transcriptionally competent active rDNA chromatin at size scales well below the diffraction limit by optical microscopy. We identify active rDNA chromatin units exhibiting uniformly ring-shaped conformations with diameters of ~240 nm in mouse and ~170 nm in human fibroblasts, consistent with rDNA looping. The active rDNA chromatin units are clearly separated from each other and from the surrounding areas of rRNA processing. Simultaneous imaging of all active genes bound by Pol I and the architectural chromatin protein Upstream Binding Transcription Factor (UBF) reveals a random spatial orientation of regular repeats of rDNA coding sequences within the nucleoli. These observations imply rDNA looping and exclude potential formation of systematic spatial assemblies of the well-ordered repetitive arrays of transcription units. Collectively, this study uncovers key features of the 3D organization of active rDNA chromatin units and their nucleolar clusters providing a spatial framework of nucleolar chromatin organization at unprecedented detail.
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Affiliation(s)
- Andreas Maiser
- Department of Biology II, Ludwig-Maximilians-Universität München, München, Germany
| | - Stefan Dillinger
- Department of Biochemistry III, University of Regensburg, Regensburg, Germany
| | - Gernot Längst
- Department of Biochemistry III, University of Regensburg, Regensburg, Germany
| | - Lothar Schermelleh
- Micron Advanced Bioimaging Unit, Department of Biochemistry, University of Oxford, Oxford, UK
| | - Heinrich Leonhardt
- Department of Biology II, Ludwig-Maximilians-Universität München, München, Germany
| | - Attila Németh
- Department of Biochemistry III, University of Regensburg, Regensburg, Germany.
- Institute of Neuropathology, Justus Liebig University, Giessen, Germany.
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Bianco C, Mohr I. Ribosome biogenesis restricts innate immune responses to virus infection and DNA. eLife 2019; 8:49551. [PMID: 31841110 PMCID: PMC6934380 DOI: 10.7554/elife.49551] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 12/16/2019] [Indexed: 01/05/2023] Open
Abstract
Ribosomes are universally important in biology and their production is dysregulated by developmental disorders, cancer, and virus infection. Although presumed required for protein synthesis, how ribosome biogenesis impacts virus reproduction and cell-intrinsic immune responses remains untested. Surprisingly, we find that restricting ribosome biogenesis stimulated human cytomegalovirus (HCMV) replication without suppressing translation. Interfering with ribosomal RNA (rRNA) accumulation triggered nucleolar stress and repressed expression of 1392 genes, including High Mobility Group Box 2 (HMGB2), a chromatin-associated protein that facilitates cytoplasmic double-stranded (ds) DNA-sensing by cGAS. Furthermore, it reduced cytoplasmic HMGB2 abundance and impaired induction of interferon beta (IFNB1) mRNA, which encodes a critical anti-proliferative, proinflammatory cytokine, in response to HCMV or dsDNA in uninfected cells. This establishes that rRNA accumulation regulates innate immune responses to dsDNA by controlling HMGB2 abundance. Moreover, it reveals that rRNA accumulation and/or nucleolar activity unexpectedly regulate dsDNA-sensing to restrict virus reproduction and regulate inflammation. (145 words)
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Affiliation(s)
- Christopher Bianco
- Department of Microbiology, NYU School of Medicine, New York, United States
| | - Ian Mohr
- Department of Microbiology, NYU School of Medicine, New York, United States.,Laura and Isaac Perlmutter Cancer Institute, NYU School of Medicine, New York, United States
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Bueno C, Martínez-Morga M, Martínez S. Non-proliferative neurogenesis in human periodontal ligament stem cells. Sci Rep 2019; 9:18038. [PMID: 31792338 PMCID: PMC6888846 DOI: 10.1038/s41598-019-54745-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 11/15/2019] [Indexed: 12/16/2022] Open
Abstract
Understanding the sequence of events from undifferentiated stem cells to neuron is not only important for the basic knowledge of stem cell biology, but also for therapeutic applications. In this study we examined the sequence of biological events during neural differentiation of human periodontal ligament stem cells (hPDLSCs). Here, we show that hPDLSCs-derived neural-like cells display a sequence of morphologic development highly similar to those reported before in primary neuronal cultures derived from rodent brains. We observed that cell proliferation is not present through neurogenesis from hPDLSCs. Futhermore, we may have discovered micronuclei movement and transient cell nuclei lobulation coincident to in vitro neurogenesis. Morphological analysis also reveals that neurogenic niches in the adult mouse brain contain cells with nuclear shapes highly similar to those observed during in vitro neurogenesis from hPDLSCs. Our results provide additional evidence that it is possible to differentiate hPDLSCs to neuron-like cells and suggest the possibility that the sequence of events from stem cell to neuron does not necessarily requires cell division from stem cell.
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Affiliation(s)
- Carlos Bueno
- Instituto de Neurociencias de Alicante (UMH-CSIC), San Juan, Alicante, 03550, Spain.
| | - Marta Martínez-Morga
- Department of Human Anatomy and Institute of Biomedical Research (IMIB), University of Murcia, Faculty of Medicine, Murcia, 30800, Spain
| | - Salvador Martínez
- Instituto de Neurociencias de Alicante (UMH-CSIC), San Juan, Alicante, 03550, Spain
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Marnef A, Finoux AL, Arnould C, Guillou E, Daburon V, Rocher V, Mangeat T, Mangeot PE, Ricci EP, Legube G. A cohesin/HUSH- and LINC-dependent pathway controls ribosomal DNA double-strand break repair. Genes Dev 2019; 33:1175-1190. [PMID: 31395742 PMCID: PMC6719620 DOI: 10.1101/gad.324012.119] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 06/26/2019] [Indexed: 02/01/2023]
Abstract
The ribosomal DNA (rDNA) represents a particularly unstable locus undergoing frequent breakage. DNA double-strand breaks (DSBs) within rDNA induce both rDNA transcriptional repression and nucleolar segregation, but the link between the two events remains unclear. Here we found that DSBs induced on rDNA trigger transcriptional repression in a cohesin- and HUSH (human silencing hub) complex-dependent manner throughout the cell cycle. In S/G2 cells, transcriptional repression is further followed by extended resection within the interior of the nucleolus, DSB mobilization at the nucleolar periphery within nucleolar caps, and repair by homologous recombination. We showed that nuclear envelope invaginations frequently connect the nucleolus and that rDNA DSB mobilization, but not transcriptional repression, involves the nuclear envelope-associated LINC complex and the actin pathway. Altogether, our data indicate that rDNA break localization at the nucleolar periphery is not a direct consequence of transcriptional repression but rather is an active process that shares features with the mobilization of persistent DSB in active genes and heterochromatin.
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Affiliation(s)
- Aline Marnef
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Anne-Laure Finoux
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Coline Arnould
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Emmanuelle Guillou
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Virginie Daburon
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Vincent Rocher
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Thomas Mangeat
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
| | - Philippe E Mangeot
- International Center for Infectiology Research (CIRI), Ecole Normale Supérieure de Lyon (ENS), U1111, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR5308, Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1, Université Lyon, Lyon F-6900, France
| | - Emiliano P Ricci
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC), Ecole Normale Supérieure de Lyon (ENS), U1210, Institut National de la Santé et de la Recherche Médicale (INSERM), UMR5239, Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1, Université de Lyon, Lyon F-69007, France
| | - Gaëlle Legube
- Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération (LBCMCP), Centre de Biologie Intégrative (CBI), Centre National de la Recherche Scientifique (CNRS), Université de Toulouse, Toulouse 31062, France
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Cerqueira AV, Lemos B. Ribosomal DNA and the Nucleolus as Keystones of Nuclear Architecture, Organization, and Function. Trends Genet 2019; 35:710-723. [PMID: 31447250 DOI: 10.1016/j.tig.2019.07.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 07/23/2019] [Accepted: 07/25/2019] [Indexed: 12/12/2022]
Abstract
The multicopy ribosomal DNA (rDNA) array gives origin to the nucleolus, a large nonmembrane-bound organelle that occupies a substantial volume within the cell nucleus. The rDNA/nucleolus has emerged as a coordinating hub in which seemingly disparate cellular functions converge, and from which a variety of cellular and organismal phenotypes emerge. However, the role of the nucleolus as a determinant and organizer of nuclear architecture and other epigenetic states of the genome is not well understood. We discuss the role of rDNA and the nucleolus in nuclear organization and function - from nucleolus-associated domains (NADs) to the regulation of imprinted loci and X chromosome inactivation, as well as rDNA contact maps that anchor and position the rDNA relative to the rest of the genome. The influence of the nucleolus on nuclear organization undoubtedly modulates diverse biological processes from metabolism to cell proliferation, genome-wide gene expression, maintenance of epigenetic states, and aging.
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Affiliation(s)
- Amanda V Cerqueira
- Department of Environmental Health, Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Bernardo Lemos
- Department of Environmental Health, Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
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Chen J, Stark LA. Insights into the Relationship between Nucleolar Stress and the NF-κB Pathway. Trends Genet 2019; 35:768-780. [PMID: 31434627 DOI: 10.1016/j.tig.2019.07.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/22/2019] [Accepted: 07/24/2019] [Indexed: 02/06/2023]
Abstract
The nuclear organelle the nucleolus and the transcription factor nuclear factor of κ-light-chain-enhancer of activated B cells (NF-κB) are both central to the control of cellular homeostasis, dysregulated in common diseases and implicated in the ageing process. Until recently, it was believed that they acted independently to regulate homeostasis in health and disease. However, there is an emerging body of evidence suggesting that nucleoli and NF-κB signalling converge at multiple levels. Here we will review current understanding of this crosstalk. We will discuss activation of the NF-κB pathway by nucleolar stress and induction of apoptosis by nucleolar sequestration of NF-κB/RelA. We will also discuss the role of TIF-IA, COMMD1, and nucleophosmin, which are key players in this crosstalk, and the therapeutic relevance, particularly with respect to the antitumour effects of aspirin.
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Affiliation(s)
- Jingyu Chen
- University of Edinburgh Cancer Research Centre, Institute of Genetics and Molecular Medicine, Western General Hospital, Crewe Road, Edinburgh, Scotland EH4 2XU, UK
| | - Lesley A Stark
- University of Edinburgh Cancer Research Centre, Institute of Genetics and Molecular Medicine, Western General Hospital, Crewe Road, Edinburgh, Scotland EH4 2XU, UK.
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