351
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Bi X, Miao K, Wei L. Alkyne-Tagged Raman Probes for Local Environmental Sensing by Hydrogen-Deuterium Exchange. J Am Chem Soc 2022; 144:8504-8514. [PMID: 35508077 DOI: 10.1021/jacs.2c01991] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Alkyne-tagged Raman probes have shown high promise for noninvasive and sensitive visualization of small biomolecules to understand their functional roles in live cells. However, the potential for alkynes to sense cellular environments that goes beyond imaging remains to be further explored. Here, we report a general strategy for Raman imaging-based local environment sensing by hydrogen-deuterium exchange (HDX) of terminal alkynes (termed alkyne-HDX). We first demonstrate, in multiple Raman probes, that deuterations of the alkynyl hydrogens lead to remarkable shifts of alkyne Raman peaks for about 130 cm-1, providing resolvable signals suited for imaging-based analysis with high specificity. Both our analytical derivation and experimental characterizations subsequently establish that HDX kinetics are linearly proportional to both alkyne pKas and environmental pDs. After validating the quantitative nature of this strategy, we apply alkyne-HDX to sensing local chemical and cellular environments. We establish that alkyne-HDX exhibits high sensitivity to various DNA structures and demonstrates the capacity to detect DNA structural changes in situ from UV-induced damage. We further show that this strategy is also applicable to resolve subtle pD variations in live cells. Altogether, our work lays the foundation for utilizing alkyne-HDX strategy to quantitatively sense the local environments for a broad spectrum of applications in complex biological systems.
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Affiliation(s)
- Xiaotian Bi
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Kun Miao
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Lu Wei
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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352
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Perro A, Coudon N, Chapel JP, Martin N, Béven L, Douliez JP. Building micro-capsules using water-in-water emulsion droplets as templates. J Colloid Interface Sci 2022; 613:681-696. [DOI: 10.1016/j.jcis.2022.01.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 12/11/2022]
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353
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Feric M, Misteli T. Function moves biomolecular condensates in phase space. Bioessays 2022; 44:e2200001. [PMID: 35243657 PMCID: PMC9277701 DOI: 10.1002/bies.202200001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 02/19/2022] [Accepted: 02/22/2022] [Indexed: 11/08/2022]
Abstract
Phase separation underlies the formation of biomolecular condensates. We hypothesize the cellular processes that occur within condensates shape their structural features. We use the example of transcription to discuss structure-function relationships in condensates. Various types of transcriptional condensates have been reported across the evolutionary spectrum in the cell nucleus as well as in mitochondrial and bacterial nucleoids. In vitro and in vivo observations suggest that transcriptional activity of condensates influences their supramolecular structure, which in turn affects their function. Condensate organization thus becomes driven by differences in miscibility among the DNA and proteins of the transcription machinery and the RNA transcripts they generate. These considerations are in line with the notion that cellular processes shape the structural properties of condensates, leading to a dynamic, mutual interplay between structure and function in the cell.
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Affiliation(s)
- Marina Feric
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Tom Misteli
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
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354
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Targeting Ribosome Biogenesis in Cancer: Lessons Learned and Way Forward. Cancers (Basel) 2022; 14:cancers14092126. [PMID: 35565259 PMCID: PMC9100539 DOI: 10.3390/cancers14092126] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 04/18/2022] [Accepted: 04/22/2022] [Indexed: 01/05/2023] Open
Abstract
Simple Summary Cells need to produce ribosomes to sustain continuous proliferation and expand in numbers, a feature that is even more prominent in uncontrollably proliferating cancer cells. Certain cancer cell types are expected to depend more on ribosome biogenesis based on their genetic background, and this potential vulnerability can be exploited in designing effective, targeted cancer therapies. This review provides information on anti-cancer molecules that target the ribosome biogenesis machinery and indicates avenues for future research. Abstract Rapid growth and unrestrained proliferation is a hallmark of many cancers. To accomplish this, cancer cells re-wire and increase their biosynthetic and metabolic activities, including ribosome biogenesis (RiBi), a complex, highly energy-consuming process. Several chemotherapeutic agents used in the clinic impair this process by interfering with the transcription of ribosomal RNA (rRNA) in the nucleolus through the blockade of RNA polymerase I or by limiting the nucleotide building blocks of RNA, thereby ultimately preventing the synthesis of new ribosomes. Perturbations in RiBi activate nucleolar stress response pathways, including those controlled by p53. While compounds such as actinomycin D and oxaliplatin effectively disrupt RiBi, there is an ongoing effort to improve the specificity further and find new potent RiBi-targeting compounds with improved pharmacological characteristics. A few recently identified inhibitors have also become popular as research tools, facilitating our advances in understanding RiBi. Here we provide a comprehensive overview of the various compounds targeting RiBi, their mechanism of action, and potential use in cancer therapy. We discuss screening strategies, drug repurposing, and common problems with compound specificity and mechanisms of action. Finally, emerging paths to discovery and avenues for the development of potential biomarkers predictive of therapeutic outcomes across cancer subtypes are also presented.
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355
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Guidotti N, Eördögh Á, Mivelaz M, Rivera-Fuentes P, Fierz B. Multivalent Peptide Ligands To Probe the Chromocenter Microenvironment in Living Cells. ACS Chem Biol 2022; 18:1066-1075. [PMID: 35447032 DOI: 10.1021/acschembio.2c00203] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chromatin is spatially organized into functional states that are defined by both the presence of specific histone post-translational modifications (PTMs) and a defined set of chromatin-associated "reader" proteins. Different models for the underlying mechanism of such compartmentalization have been proposed, including liquid-liquid phase separation (LLPS) of chromatin-associated proteins to drive spatial organization. Heterochromatin, characterized by lysine 9 methylation on histone H3 (H3K9me3) and the presence of heterochromatin protein 1 (HP1) as a multivalent reader, represents a prime example of a spatially defined chromatin state. Heterochromatin foci exhibit features of protein condensates driven by LLPS; however, the exact nature of the physicochemical environment within heterochromatin in different cell types is not completely understood. Here we present tools to interrogate the environment of chromatin subcompartments in the form of modular, cell-permeable, multivalent, and fluorescent peptide probes. These probes can be tuned to target specific chromatin states by providing binding sites to reader proteins and can thereby integrate into the PTM-reader interaction network. Here we generate probes specific to HP1, directing them to heterochromatin at chromocenters in mouse fibroblasts. Moreover, we use a polarity-sensing photoactivatable probe that photoconverts to a fluorescent state in phase-separated protein droplets and thereby reports on the local microenvironment. Equipped with this dye, our probes indeed turn fluorescent in murine chromocenters. Image analysis and single-molecule tracking experiments reveal that the compartments are less dense and more dynamic than HP1 condensates obtained in vitro. Our results thus demonstrate that the local organization of heterochromatin in chromocenters is internally more complex than an HP1 condensate.
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Affiliation(s)
- Nora Guidotti
- École Polytechnique Fédérale de Lausanne (EPFL), SB ISIC LCBM, Station 6, CH-1015 Lausanne, Switzerland
| | - Ádám Eördögh
- EPFL, SB ISIC LOCBP, Station 6, CH-1015 Lausanne, Switzerland
- Laboratory of Organic Chemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Maxime Mivelaz
- École Polytechnique Fédérale de Lausanne (EPFL), SB ISIC LCBM, Station 6, CH-1015 Lausanne, Switzerland
| | | | - Beat Fierz
- École Polytechnique Fédérale de Lausanne (EPFL), SB ISIC LCBM, Station 6, CH-1015 Lausanne, Switzerland
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356
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Antifeeva IA, Fonin AV, Fefilova AS, Stepanenko OV, Povarova OI, Silonov SA, Kuznetsova IM, Uversky VN, Turoverov KK. Liquid-liquid phase separation as an organizing principle of intracellular space: overview of the evolution of the cell compartmentalization concept. Cell Mol Life Sci 2022; 79:251. [PMID: 35445278 PMCID: PMC11073196 DOI: 10.1007/s00018-022-04276-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 03/24/2022] [Accepted: 03/27/2022] [Indexed: 12/14/2022]
Abstract
At the turn of the twenty-first century, fundamental changes took place in the understanding of the structure and function of proteins and then in the appreciation of the intracellular space organization. A rather mechanistic model of the organization of living matter, where the function of proteins is determined by their rigid globular structure, and the intracellular processes occur in rigidly determined compartments, was replaced by an idea that highly dynamic and multifunctional "soft matter" lies at the heart of all living things. According this "new view", the most important role in the spatio-temporal organization of the intracellular space is played by liquid-liquid phase transitions of biopolymers. These self-organizing cellular compartments are open dynamic systems existing at the edge of chaos. They are characterized by the exceptional structural and compositional dynamics, and their multicomponent nature and polyfunctionality provide means for the finely tuned regulation of various intracellular processes. Changes in the external conditions can cause a disruption of the biogenesis of these cellular bodies leading to the irreversible aggregation of their constituent proteins, followed by the transition to a gel-like state and the emergence of amyloid fibrils. This work represents a historical overview of changes in our understanding of the intracellular space compartmentalization. It also reflects methodological breakthroughs that led to a change in paradigms in this area of science and discusses modern ideas about the organization of the intracellular space. It is emphasized here that the membrane-less organelles have to combine a certain resistance to the changes in their environment and, at the same time, show high sensitivity to the external signals, which ensures the normal functioning of the cell.
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Affiliation(s)
- Iuliia A Antifeeva
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Alexander V Fonin
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Anna S Fefilova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Olesya V Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Olga I Povarova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Sergey A Silonov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Irina M Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd. MDC07, Tampa, FL, 33612, USA.
| | - Konstantin K Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Av., 4, St. Petersburg, 194064, Russia.
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357
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Liu J, Zhorabek F, Chau Y. Nucleic Acids Modulate Liquidity and Dynamics of Artificial Membraneless Organelles. ACS Macro Lett 2022; 11:562-567. [PMID: 35575335 DOI: 10.1021/acsmacrolett.2c00167] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Liquid-liquid phase separation (LLPS) emerges as a fundamental underlying mechanism for the biological organization, especially the formation of membraneless organelles (MLOs) hosting intrinsically disordered proteins (IDPs) as scaffolds. Nucleic acids are compositional biomacromolecules of MLOs with wide implications in normal cell functions as well as in pathophysiology caused by aberrant phase behavior. Exploiting a minimalist artificial membraneless organelles (AMLO) from LLPS of IDP-mimicking polymer-oligopeptide hybrid (IPH), we investigated the effect of nucleic acids with different lengths and sequence variations on AMLO. The behavior of this AMLO in the presence of DNAs and RNAs resembled natural MLOs in multiple aspects, namely, modulated propensity of formation, morphology, liquidity, and dynamics. Both DNA and RNA could enhance the LLPS of AMLO, while compared with RNA, DNA had a higher tendency to solidify and diminish dynamics thereof. These findings suggest its potential as a concise model system for the understanding of the interaction between nucleic acids and natural MLOs and for studying the molecular mechanism of diseases involving MLOs.
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Affiliation(s)
- Jianhui Liu
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
| | - Fariza Zhorabek
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
| | - Ying Chau
- Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
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358
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Korshikov II, Bilonozhko YO, Milchevskaya YG. Peculiarities of Nucleus–Nucleolus Indicators of Seed Progeny in Mother Stankevich Pine trees (Pinus brutia var. stankewiczii Sukacz.) Different in Levels of Heterozygosity. CYTOL GENET+ 2022. [DOI: 10.3103/s0095452722020074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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359
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Compartment-Specific Proximity Ligation Expands the Toolbox to Assess the Interactome of the Long Non-Coding RNA NEAT1. Int J Mol Sci 2022; 23:ijms23084432. [PMID: 35457249 PMCID: PMC9027746 DOI: 10.3390/ijms23084432] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/06/2022] [Accepted: 04/13/2022] [Indexed: 12/23/2022] Open
Abstract
The nuclear paraspeckle assembly transcript 1 (NEAT1) locus encodes two long non-coding (lnc)RNA isoforms that are upregulated in many tumours and dynamically expressed in response to stress. NEAT1 transcripts form ribonucleoprotein complexes with numerous RNA-binding proteins (RBPs) to assemble paraspeckles and modulate the localisation and activity of gene regulatory enzymes as well as a subset of messenger (m)RNA transcripts. The investigation of the dynamic composition of NEAT1-associated proteins and mRNAs is critical to understand the function of NEAT1. Interestingly, a growing number of biochemical and genetic tools to assess NEAT1 interactomes has been reported. Here, we discuss the Hybridisation Proximity (HyPro) labeling technique in the context of NEAT1. HyPro labeling is a recently developed method to detect spatially ordered interactions of RNA-containing nuclear compartments in cultured human cells. After introducing NEAT1 and paraspeckles, we describe the advantages of the HyPro technology in the context of other methods to study RNA interactomes, and review the key findings in mapping NEAT1-associated RNA transcripts and protein binding partners. We further discuss the limitations and potential improvements of HyPro labeling, and conclude by delineating its applicability in paraspeckles-related cancer research.
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360
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Bose M, Lampe M, Mahamid J, Ephrussi A. Liquid-to-solid phase transition of oskar ribonucleoprotein granules is essential for their function in Drosophila embryonic development. Cell 2022; 185:1308-1324.e23. [PMID: 35325593 PMCID: PMC9042795 DOI: 10.1016/j.cell.2022.02.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 11/24/2021] [Accepted: 02/18/2022] [Indexed: 01/05/2023]
Abstract
Asymmetric localization of oskar ribonucleoprotein (RNP) granules to the oocyte posterior is crucial for abdominal patterning and germline formation in the Drosophila embryo. We show that oskar RNP granules in the oocyte are condensates with solid-like physical properties. Using purified oskar RNA and scaffold proteins Bruno and Hrp48, we confirm in vitro that oskar granules undergo a liquid-to-solid phase transition. Whereas the liquid phase allows RNA incorporation, the solid phase precludes incorporation of additional RNA while allowing RNA-dependent partitioning of client proteins. Genetic modification of scaffold granule proteins or tethering the intrinsically disordered region of human fused in sarcoma (FUS) to oskar mRNA allowed modulation of granule material properties in vivo. The resulting liquid-like properties impaired oskar localization and translation with severe consequences on embryonic development. Our study reflects how physiological phase transitions shape RNA-protein condensates to regulate the localization and expression of a maternal RNA that instructs germline formation.
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Affiliation(s)
- Mainak Bose
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg 69117, Germany
| | - Marko Lampe
- Advanced Light Microscopy Facility, European Molecular Biology Laboratory, Heidelberg 69117, Germany
| | - Julia Mahamid
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg 69117, Germany.
| | - Anne Ephrussi
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg 69117, Germany.
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361
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Abstract
Small nucleolar RNAs (snoRNAs) are non-coding RNAs vital for ribosomal RNA (rRNA) maturation. The U8 snoRNA, encoded by the SNORD118 gene in humans, is an atypical C/D box snoRNA as it promotes rRNA cleavage rather than 2′–O–methylation and is unique to vertebrates. The U8 snoRNA is critical for cleavage events that produce the mature 5.8S and 28S rRNAs of the large ribosomal subunit. Unexpectedly, single nucleotide polymorphisms (SNPs) in the SNORD118 gene were recently found causal to the neurodegenerative disease leukoencephalopathy, brain calcifications, and cysts (LCC; aka Labrune syndrome), but its molecular pathogenesis is unclear. Here, we will review current knowledge on the function of the U8 snoRNA in ribosome biogenesis, and connect it to the preservation of brain function in humans as well as to its dysregulation in inherited white matter disease.
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Affiliation(s)
- Emily J McFadden
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Susan J Baserga
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.,Department of Genetics, Yale School of Medicine, New Haven, CT, USA.,Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT, USA
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362
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Igelmann S, Lessard F, Ferbeyre G. Liquid-Liquid Phase Separation in Cancer Signaling, Metabolism and Anticancer Therapy. Cancers (Basel) 2022; 14:cancers14071830. [PMID: 35406602 PMCID: PMC8997759 DOI: 10.3390/cancers14071830] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 01/07/2023] Open
Abstract
The cancer state is thought to be maintained by genetic and epigenetic changes that drive a cancer-promoting gene expression program. However, recent results show that cellular states can be also stably maintained by the reorganization of cell structure leading to the formation of biological condensates via the process of liquid-liquid phase separation. Here, we review the data showing cancer-specific biological condensates initiated by mutant oncoproteins, RNA-binding proteins, or lincRNAs that regulate oncogenic gene expression programs and cancer metabolism. Effective anticancer drugs may specifically partition into oncogenic biological condensates (OBC).
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Affiliation(s)
- Sebastian Igelmann
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC H3C 3J7, Canada;
- Montreal Cancer Institute, CR-CHUM, Université de Montréal, Montréal, QC H2X 0A9, Canada
| | - Frédéric Lessard
- Laboratory of Growth and Development, St-Patrick Research Group in Basic Oncology, Cancer Division of the Quebec University Hospital Research Centre, Québec, QC G1R 2J6, Canada;
| | - Gerardo Ferbeyre
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC H3C 3J7, Canada;
- Montreal Cancer Institute, CR-CHUM, Université de Montréal, Montréal, QC H2X 0A9, Canada
- Correspondence: ; Tel.: +1-514-343-7571
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363
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Pundel OJ, Blowes LM, Connelly JT. Extracellular Adhesive Cues Physically Define Nucleolar Structure and Function. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2105545. [PMID: 35122409 PMCID: PMC8981897 DOI: 10.1002/advs.202105545] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/19/2022] [Indexed: 05/14/2023]
Abstract
Adhesive cues from the extracellular matrix (ECM) specify the size and shape of the nucleus via mechanical forces transmitted through the cytoskeleton. However, the effects of these biophysical stimuli on internal nuclear architecture and cellular responses remain poorly understood. This study investigates the direct impact of ECM adhesion on nucleolar remodeling in human keratinocytes using micropatterned substrates. Limited adhesion on small micropatterns promotes fusion of nucleoli, alongside a reduction in nuclear volume and condensation of heterochromatin. These changes in nucleolar architecture are mediated by altered chromatin biomechanics and depend on integration of the nucleus with the actin cytoskeleton. Functionally, nucleolar remodeling regulates ribogenesis and protein synthesis in keratinocytes and is associated with specific transcriptional changes in ribogenesis genes. Together, these findings demonstrate that cell shape and nuclear morphology control nucleolar structure and function and implicate the nucleolus as a key mechano-sensing element within the cell.
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Affiliation(s)
- Oscar J. Pundel
- Centre for Cell Biology and Cutaneous Research4 Newark StreetLondonE1 2ATUK
| | - Liisa M. Blowes
- Centre for Cell Biology and Cutaneous Research4 Newark StreetLondonE1 2ATUK
| | - John T. Connelly
- Centre for Cell Biology and Cutaneous Research4 Newark StreetLondonE1 2ATUK
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364
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Mehta S, Zhang J. Liquid-liquid phase separation drives cellular function and dysfunction in cancer. Nat Rev Cancer 2022; 22:239-252. [PMID: 35149762 PMCID: PMC10036213 DOI: 10.1038/s41568-022-00444-7] [Citation(s) in RCA: 119] [Impact Index Per Article: 59.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/12/2022] [Indexed: 12/11/2022]
Abstract
Cancer is a disease of uncontrollably reproducing cells. It is governed by biochemical pathways that have escaped the regulatory bounds of normal homeostatic balance. This balance is maintained through precise spatiotemporal regulation of these pathways. The formation of biomolecular condensates via liquid-liquid phase separation (LLPS) has recently emerged as a widespread mechanism underlying the spatiotemporal coordination of biological activities in cells. Biomolecular condensates are widely observed to directly regulate key cellular processes involved in cancer cell pathology, and the dysregulation of LLPS is increasingly implicated as a previously hidden driver of oncogenic activity. In this Perspective, we discuss how LLPS shapes the biochemical landscape of cancer cells.
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Affiliation(s)
- Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Jin Zhang
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA.
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA.
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA.
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365
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Casadio R, Martelli PL, Savojardo C. Machine learning solutions for predicting protein–protein interactions. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2022. [DOI: 10.1002/wcms.1618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Rita Casadio
- Biocomputing Group University of Bologna Bologna Italy
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366
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Phillips CM, Updike DL. Germ granules and gene regulation in the Caenorhabditis elegans germline. Genetics 2022; 220:6541922. [PMID: 35239965 PMCID: PMC8893257 DOI: 10.1093/genetics/iyab195] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 10/10/2021] [Indexed: 01/27/2023] Open
Abstract
The transparency of Caenorhabditis elegans provides a unique window to observe and study the function of germ granules. Germ granules are specialized ribonucleoprotein (RNP) assemblies specific to the germline cytoplasm, and they are largely conserved across Metazoa. Within the germline cytoplasm, they are positioned to regulate mRNA abundance, translation, small RNA production, and cytoplasmic inheritance to help specify and maintain germline identity across generations. Here we provide an overview of germ granules and focus on the significance of more recent observations that describe how they further demix into sub-granules, each with unique compositions and functions.
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Affiliation(s)
- Carolyn M Phillips
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA,Corresponding author: (C.M.P.); (D.L.U.)
| | - Dustin L Updike
- The Mount Desert Island Biological Laboratory, Bar Harbor, ME 04672, USA,Corresponding author: (C.M.P.); (D.L.U.)
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367
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Agarwal A, Arora L, Rai SK, Avni A, Mukhopadhyay S. Spatiotemporal modulations in heterotypic condensates of prion and α-synuclein control phase transitions and amyloid conversion. Nat Commun 2022; 13:1154. [PMID: 35241680 PMCID: PMC8894376 DOI: 10.1038/s41467-022-28797-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 02/10/2022] [Indexed: 12/30/2022] Open
Abstract
Biomolecular condensation via liquid-liquid phase separation of proteins and nucleic acids is associated with a range of critical cellular functions and neurodegenerative diseases. Here, we demonstrate that complex coacervation of the prion protein and α-synuclein within narrow stoichiometry results in the formation of highly dynamic, reversible, thermo-responsive liquid droplets via domain-specific electrostatic interactions between the positively-charged intrinsically disordered N-terminal segment of prion and the acidic C-terminal tail of α-synuclein. The addition of RNA to these coacervates yields multiphasic, vesicle-like, hollow condensates. Picosecond time-resolved measurements revealed the presence of transient electrostatic nanoclusters that are stable on the nanosecond timescale and can undergo breaking-and-making of interactions on slower timescales giving rise to a liquid-like behavior in the mesoscopic regime. The liquid-to-solid transition drives a rapid conversion of complex coacervates into heterotypic amyloids. Our results suggest that synergistic prion-α-synuclein interactions within condensates provide mechanistic underpinnings of their physiological role and overlapping neuropathological features.
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Affiliation(s)
- Aishwarya Agarwal
- Centre for Protein Science, Design and Engineering, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Lisha Arora
- Centre for Protein Science, Design and Engineering, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Sandeep K Rai
- Centre for Protein Science, Design and Engineering, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Anamika Avni
- Centre for Protein Science, Design and Engineering, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Samrat Mukhopadhyay
- Centre for Protein Science, Design and Engineering, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India.
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India.
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India.
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368
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Gai X, Xin D, Wu D, Wang X, Chen L, Wang Y, Ma K, Li Q, Li P, Yu X. Pre-ribosomal RNA reorganizes DNA damage repair factors in nucleus during meiotic prophase and DNA damage response. Cell Res 2022; 32:254-268. [PMID: 34980897 PMCID: PMC8888703 DOI: 10.1038/s41422-021-00597-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 11/11/2021] [Indexed: 11/09/2022] Open
Abstract
In response to DNA double-strand breaks (DSBs), DNA damage repair factors are recruited to DNA lesions and form nuclear foci. However, the underlying molecular mechanism remains largely elusive. Here, by analyzing the localization of DSB repair factors in the XY body and DSB foci, we demonstrate that pre-ribosomal RNA (pre-rRNA) mediates the recruitment of DSB repair factors around DNA lesions. Pre-rRNA exists in the XY body, a DSB repair hub, during meiotic prophase, and colocalizes with DSB repair factors, such as MDC1, BRCA1 and TopBP1. Moreover, pre-rRNA-associated proteins and RNAs, such as ribosomal protein subunits, RNase MRP and snoRNAs, also localize in the XY body. Similar to those in the XY body, pre-rRNA and ribosomal proteins also localize at DSB foci and associate with DSB repair factors. RNA polymerase I inhibitor treatment that transiently suppresses transcription of rDNA but does not affect global protein translation abolishes foci formation of DSB repair factors as well as DSB repair. The FHA domain and PST repeats of MDC1 recognize pre-rRNA and mediate phase separation of DSB repair factors, which may be the molecular basis for the foci formation of DSB repair factors during DSB response.
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Affiliation(s)
- Xiaochen Gai
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Di Xin
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Duo Wu
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Xin Wang
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Linlin Chen
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Yiqing Wang
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Kai Ma
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Qilin Li
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Peng Li
- grid.494629.40000 0004 8008 9315Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315School of Life Sciences, Westlake University, Hangzhou, Zhejiang China ,grid.494629.40000 0004 8008 9315Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang China
| | - Xiaochun Yu
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, Zhejiang, China. .,School of Life Sciences, Westlake University, Hangzhou, Zhejiang, China. .,Institute of Basic Medical Sciences, Westlake Institute for Advanced Study, Hangzhou, Zhejiang, China.
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369
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The Novel Protease Activities of JMJD5–JMJD6–JMJD7 and Arginine Methylation Activities of Arginine Methyltransferases Are Likely Coupled. Biomolecules 2022; 12:biom12030347. [PMID: 35327545 PMCID: PMC8945206 DOI: 10.3390/biom12030347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/03/2022] [Accepted: 02/18/2022] [Indexed: 12/23/2022] Open
Abstract
The surreptitious discoveries of the protease activities on arginine-methylated targets of a subfamily of Jumonji domain-containing family including JMJD5, JMJD6, and JMJD7 pose several questions regarding their authenticity, function, purpose, and relations with others. At the same time, despite several decades of efforts and massive accumulating data regarding the roles of the arginine methyltransferase family (PRMTs), the exact function of this protein family still remains a mystery, though it seems to play critical roles in transcription regulation, including activation and inactivation of a large group of genes, as well as other biological activities. In this review, we aim to elucidate that the function of JMJD5/6/7 and PRMTs are likely coupled. Besides roles in the regulation of the biogenesis of membrane-less organelles in cells, they are major players in regulating stimulating transcription factors to control the activities of RNA Polymerase II in higher eukaryotes, especially in the animal kingdom. Furthermore, we propose that arginine methylation by PRMTs could be a ubiquitous action marked for destruction after missions by a subfamily of the Jumonji protein family.
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370
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Rippe K, Papantonis A. Functional organization of RNA polymerase II in nuclear subcompartments. Curr Opin Cell Biol 2022; 74:88-96. [PMID: 35217398 DOI: 10.1016/j.ceb.2022.01.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/08/2022] [Accepted: 01/14/2022] [Indexed: 12/22/2022]
Abstract
Distinct clusters of RNA polymerase II are responsible for gene transcription inside eukaryotic cell nuclei. Despite the functional implications of such subnuclear organization, the attributes of these clusters and the mechanisms underlying their formation remain only partially understood. Recently, the concept of proteins and RNA phase-separating into liquid-like droplets was proposed to drive the formation of transcriptionally-active subcompartments. Here, we attempt to reconcile previous with more recent findings, and discuss how the different ways of assembling the active RNA polymerase II transcriptional machinery relate to nuclear compartmentalization.
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Affiliation(s)
- Karsten Rippe
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany.
| | - Argyris Papantonis
- Translational Epigenetics Group, Institute of Pathology, University Medical Center Göttingen, Göttingen, Germany.
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371
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Migration of Influenza Virus Nucleoprotein into the Nucleolus Is Essential for Ribonucleoprotein Complex Formation. mBio 2022. [PMCID: PMC8725578 DOI: 10.1128/mbio.03315-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Influenza A virus double-helical ribonucleoprotein complex (RNP) performs transcription and replication of viral genomic RNA (vRNA). Although RNP formation occurs in the nuclei of virus-infected cells, the nuclear domains involved in this process remain unclear. Here, we show that the nucleolus is an essential site for functional RNP formation. Viral nucleoprotein (NP), a major RNP component, temporarily localized to the nucleoli of virus-infected cells. Mutations in a nucleolar localization signal (NoLS) on NP abolished double-helical RNP formation, resulting in a loss of viral RNA synthesis ability, whereas ectopic fusion of the NoLS enabled the NP mutant to form functional double-helical RNPs. Furthermore, nucleolar disruption of virus-infected cells inhibited NP assembly into double-helical RNPs, resulting in decreased viral RNA synthesis. Collectively, our findings demonstrate that NP migration into the nucleolus is a critical step for functional RNP formation, showing the importance of the nucleolus in the influenza virus life cycle.
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372
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Hansma HG. Potassium at the Origins of Life: Did Biology Emerge from Biotite in Micaceous Clay? Life (Basel) 2022; 12:301. [PMID: 35207588 PMCID: PMC8880093 DOI: 10.3390/life12020301] [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: 12/31/2021] [Revised: 01/31/2022] [Accepted: 01/31/2022] [Indexed: 12/15/2022] Open
Abstract
Intracellular potassium concentrations, [K+], are high in all types of living cells, but the origins of this K+ are unknown. The simplest hypothesis is that life emerged in an environment that was high in K+. One such environment is the spaces between the sheets of the clay mineral mica. The best mica for life's origins is the black mica, biotite, because it has a high content of Mg++ and because it has iron in various oxidation states. Life also has many of the characteristics of the environment between mica sheets, giving further support for the possibility that mica was the substrate on and within which life emerged. Here, a scenario for life's origins is presented, in which the necessary processes and components for life arise in niches between mica sheets; vesicle membranes encapsulate these processes and components; the resulting vesicles fuse, forming protocells; and eventually, all of the necessary components and processes are encapsulated within individual cells, some of which survive to seed the early Earth with life. This paper presents three new foci for the hypothesis of life's origins between mica sheets: (1) that potassium is essential for life's origins on Earth; (2) that biotite mica has advantages over muscovite mica; and (3) that micaceous clay is a better environment than isolated mica for life's origins.
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373
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Mechanisms of DNA Mobilization and Sequestration. Genes (Basel) 2022; 13:genes13020352. [PMID: 35205396 PMCID: PMC8872102 DOI: 10.3390/genes13020352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/10/2022] [Accepted: 02/12/2022] [Indexed: 12/04/2022] Open
Abstract
The entire genome becomes mobilized following DNA damage. Understanding the mechanisms that act at the genome level requires that we embrace experimental and computational strategies to capture the behavior of the long-chain DNA polymer, which is the building block for the chromosome. Long-chain polymers exhibit constrained, sub-diffusive motion in the nucleus. Cross-linking proteins, including cohesin and condensin, have a disproportionate effect on genome organization in their ability to stabilize transient interactions. Cross-linking proteins can segregate the genome into sub-domains through polymer–polymer phase separation (PPPS) and can drive the formation of gene clusters through small changes in their binding kinetics. Principles from polymer physics provide a means to unravel the mysteries hidden in the chains of life.
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374
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Vanden Broeck A, Klinge S. An emerging mechanism for the maturation of the Small Subunit Processome. Curr Opin Struct Biol 2022; 73:102331. [PMID: 35176592 DOI: 10.1016/j.sbi.2022.102331] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/14/2021] [Accepted: 01/10/2022] [Indexed: 12/15/2022]
Abstract
The biogenesis of the eukaryotic ribosome is a tightly regulated and energetically demanding process involving more than 200 ribosome assembly factors. These factors work in concert to ensure accurate assembly and maturation of both ribosomal subunits. Cryo-electron microscopy (cryo-EM) structures of numerous eukaryotic ribosome assembly intermediates have provided a wealth of structural insights highlighting the molecular interplay of a cast of assembly factors. In this review, we focus on recently determined structures of maturing small subunit (SSU) processomes, giant precursors of the small ribosomal subunit. Based on these structures and complementary biochemical and genetic studies, we discuss an emerging mechanism involving exosome-mediated SSU processome maturation and disassembly.
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Affiliation(s)
- Arnaud Vanden Broeck
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, NY 10065, USA. https://twitter.com/AVBroeck
| | - Sebastian Klinge
- Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, NY 10065, USA.
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375
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do Amaral MJ, Freire MHO, Almeida MS, Pinheiro AS, Cordeiro Y. Phase separation of the mammalian prion protein: physiological and pathological perspectives. J Neurochem 2022. [PMID: 35149997 DOI: 10.1111/jnc.15586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/24/2022] [Accepted: 01/31/2022] [Indexed: 11/27/2022]
Abstract
Abnormal phase transitions have been implicated in the occurrence of proteinopathies. Disordered proteins with nucleic acid binding ability drive the formation of reversible micron-sized condensates capable of controlling nucleic acid processing/transport. This mechanism, achieved via liquid-liquid phase separation (LLPS), underlies the formation of long-studied membraneless organelles (e.g., nucleolus) and various transient condensates formed by driver proteins. The prion protein (PrP) is not a classical nucleic acid-binding protein. However, it binds nucleic acids with high affinity, undergoes nucleocytoplasmic shuttling, contains a long intrinsically disordered region rich in glycines and evenly spaced aromatic residues, among other biochemical/biophysical properties of bona fide drivers of phase transitions. Because of this, our group and others have characterized LLPS of recombinant PrP. In vitro phase separation of PrP is modulated by nucleic acid aptamers, and, depending on the aptamer conformation, the liquid droplets evolve to solid-like species. Herein we discuss recent studies and previous evidence supporting PrP phase transitions. We focus on the central role of LLPS related to PrP physiology and pathology, with a special emphasis on the interaction of PrP with different ligands, such as proteins and nucleic acids, which can play a role in prion disease pathogenesis. Finally, we comment on therapeutic strategies directed at the nonfunctional phase separation that could potentially tackle prion diseases or other protein misfolding disorders.
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Affiliation(s)
- Mariana J do Amaral
- Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | | | - Anderson S Pinheiro
- Department of Biochemistry, Institute of Chemistry, Rio de Janeiro, RJ, Brazil
| | - Yraima Cordeiro
- Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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376
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Abstract
The 14-3-3 family proteins are vital scaffold proteins that ubiquitously expressed in various tissues. They interact with numerous protein targets and mediate many cellular signaling pathways. The 14-3-3 binding motifs are often embedded in intrinsically disordered regions which are closely associated with liquid-liquid phase separation (LLPS). In the past ten years, LLPS has been observed for a variety of proteins and biological processes, indicating that LLPS plays a fundamental role in the formation of membraneless organelles and cellular condensates. While extensive investigations have been performed on 14-3-3 proteins, its involvement in LLPS is overlooked. To date, 14-3-3 proteins have not been reported to undergo LLPS alone or regulate LLPS of their binding partners. To reveal the potential involvement of 14-3-3 proteins in LLPS, in this review, we summarized the LLPS propensity of 14-3-3 binding partners and found that about one half of them may undergo LLPS spontaneously. We further analyzed the phase separation behavior of representative 14-3-3 binders and discussed how 14-3-3 proteins may be involved. By modulating the conformation and valence of interactions and recruiting other molecules, we speculate that 14-3-3 proteins can efficiently regulate the functions of their targets in the context of LLPS. Considering the critical roles of 14-3-3 proteins, there is an urgent need for investigating the involvement of 14-3-3 proteins in the phase separation process of their targets and the underling mechanisms.
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377
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Systematic mapping of nuclear domain-associated transcripts reveals speckles and lamina as hubs of functionally distinct retained introns. Mol Cell 2022; 82:1035-1052.e9. [PMID: 35182477 DOI: 10.1016/j.molcel.2021.12.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 12/22/2022]
Abstract
The nucleus is highly compartmentalized through the formation of distinct classes of membraneless domains. However, the composition and function of many of these structures are not well understood. Using APEX2-mediated proximity labeling and RNA sequencing, we surveyed human transcripts associated with nuclear speckles, several additional domains, and the lamina. Remarkably, speckles and lamina are associated with distinct classes of retained introns enriched in genes that function in RNA processing, translation, and the cell cycle, among other processes. In contrast to the lamina-proximal introns, retained introns associated with speckles are relatively short, GC-rich, and enriched for functional sites of RNA-binding proteins that are concentrated in these domains. They are also highly differentially regulated across diverse cellular contexts, including the cell cycle. Thus, our study provides a resource of nuclear domain-associated transcripts and further reveals speckles and lamina as hubs of distinct populations of retained introns linked to gene regulation and cell cycle progression.
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378
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Carey JL, Guo L. Liquid-Liquid Phase Separation of TDP-43 and FUS in Physiology and Pathology of Neurodegenerative Diseases. Front Mol Biosci 2022; 9:826719. [PMID: 35187086 PMCID: PMC8847598 DOI: 10.3389/fmolb.2022.826719] [Citation(s) in RCA: 62] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/11/2022] [Indexed: 12/12/2022] Open
Abstract
Liquid-liquid phase separation of RNA-binding proteins mediates the formation of numerous membraneless organelles with essential cellular function. However, aberrant phase transition of these proteins leads to the formation of insoluble protein aggregates, which are pathological hallmarks of neurodegenerative diseases including ALS and FTD. TDP-43 and FUS are two such RNA-binding proteins that mislocalize and aggregate in patients of ALS and FTD. They have similar domain structures that provide multivalent interactions driving their phase separation in vitro and in the cellular environment. In this article, we review the factors that mediate and regulate phase separation of TDP-43 and FUS. We also review evidences that connect the phase separation property of TDP-43 and FUS to their functional roles in cells. Aberrant phase transition of TDP-43 and FUS leads to protein aggregation and disrupts their regular cell function. Therefore, restoration of functional protein phase of TDP-43 and FUS could be beneficial for neuronal cells. We discuss possible mechanisms for TDP-43 and FUS aberrant phase transition and aggregation while reviewing the methods that are currently being explored as potential therapeutic strategies to mitigate aberrant phase transition and aggregation of TDP-43 and FUS.
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379
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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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380
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Shin Y. Rich Phase Separation Behavior of Biomolecules. Mol Cells 2022; 45:6-15. [PMID: 34966005 PMCID: PMC8819493 DOI: 10.14348/molcells.2021.0204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/10/2021] [Accepted: 09/10/2021] [Indexed: 11/27/2022] Open
Abstract
Phase separation is a thermodynamic process leading to the formation of compositionally distinct phases. For the past few years, numerous works have shown that biomolecular phase separation serves as biogenesis mechanisms of diverse intracellular condensates, and aberrant phase transitions are associated with disease states such as neurodegenerative diseases and cancers. Condensates exhibit rich phase behaviors including multiphase internal structuring, noise buffering, and compositional tunability. Recent studies have begun to uncover how a network of intermolecular interactions can give rise to various biophysical features of condensates. Here, we review phase behaviors of biomolecules, particularly with regard to regular solution models of binary and ternary mixtures. We discuss how these theoretical frameworks explain many aspects of the assembly, composition, and miscibility of diverse biomolecular phases, and highlight how a model-based approach can help elucidate the detailed thermodynamic principle for multicomponent intracellular phase separation.
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Affiliation(s)
- Yongdae Shin
- Department of Mechanical Engineering, Seoul National University, Seoul 08826, Korea
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul 08826, Korea
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381
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An assembly of nuclear bodies associates with the active VSG expression site in African trypanosomes. Nat Commun 2022; 13:101. [PMID: 35013170 PMCID: PMC8748868 DOI: 10.1038/s41467-021-27625-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 11/26/2021] [Indexed: 12/19/2022] Open
Abstract
A Variant Surface Glycoprotein (VSG) coat protects bloodstream form Trypanosoma brucei. Prodigious amounts of VSG mRNA (~7-10% total) are generated from a single RNA polymerase I (Pol I) transcribed VSG expression site (ES), necessitating extremely high levels of localised splicing. We show that splicing is required for processive ES transcription, and describe novel ES-associated T. brucei nuclear bodies. In bloodstream form trypanosomes, the expression site body (ESB), spliced leader array body (SLAB), NUFIP body and Cajal bodies all frequently associate with the active ES. This assembly of nuclear bodies appears to facilitate the extraordinarily high levels of transcription and splicing at the active ES. In procyclic form trypanosomes, the NUFIP body and SLAB do not appear to interact with the Pol I transcribed procyclin locus. The congregation of a restricted number of nuclear bodies at a single active ES, provides an attractive mechanism for how monoallelic ES transcription is mediated. A Variant Surface Glycoprotein (VSG) coat protects bloodstream form T. brucei. Applying super-resolution microscopy Budzak et al. characterize a set of nuclear bodies, which associate with the active expression site in bloodstream form T. brucei and highlight the importance of trans-splicing for transcription of VSG.
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382
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RNA gradients: Shapers of 3D genome architecture. Curr Opin Cell Biol 2022; 74:7-12. [PMID: 34998095 DOI: 10.1016/j.ceb.2021.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/01/2021] [Accepted: 12/03/2021] [Indexed: 01/13/2023]
Abstract
A growing body of evidence points to a role of nuclear RNAs (nucRNAs) in shaping the three-dimensional (3D) architecture of the genome within the nucleus of a eukaryotic cell. nucRNAs are non-homogeneously distributed within the nucleus where they can form global and local gradients that might contribute to instructing the formation and coordinating the function of different types of 3D genome structures. In this article, we highlight the available literature supporting a role of nucRNAs as 3D genome shapers and propose that nucRNA gradients are key mediators of genome structure and function.
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383
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Chen X, Mayr C. A working model for condensate RNA-binding proteins as matchmakers for protein complex assembly. RNA (NEW YORK, N.Y.) 2022; 28:76-87. [PMID: 34706978 PMCID: PMC8675283 DOI: 10.1261/rna.078995.121] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Most cellular processes are carried out by protein complexes, but it is still largely unknown how the subunits of lowly expressed complexes find each other in the crowded cellular environment. Here, we will describe a working model where RNA-binding proteins in cytoplasmic condensates act as matchmakers between their bound proteins (called protein targets) and newly translated proteins of their RNA targets to promote their assembly into complexes. Different RNA-binding proteins act as scaffolds for various cytoplasmic condensates with several of them supporting translation. mRNAs and proteins are recruited into the cytoplasmic condensates through binding to specific domains in the RNA-binding proteins. Scaffold RNA-binding proteins have a high valency. In our model, they use homotypic interactions to assemble condensates and they use heterotypic interactions to recruit protein targets into the condensates. We propose that unoccupied binding sites in the scaffold RNA-binding proteins transiently retain recruited and newly translated proteins in the condensates, thus promoting their assembly into complexes. Taken together, we propose that lowly expressed subunits of protein complexes combine information in their mRNAs and proteins to colocalize in the cytoplasm. The efficiency of protein complex assembly is increased by transient entrapment accomplished by multivalent RNA-binding proteins within cytoplasmic condensates.
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Affiliation(s)
- Xiuzhen Chen
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Christine Mayr
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
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384
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Bryant CJ, McCool MA, Abriola L, Surovtseva YV, Baserga SJ. A high-throughput assay for directly monitoring nucleolar rRNA biogenesis. Open Biol 2022; 12:210305. [PMID: 35078352 PMCID: PMC8790372 DOI: 10.1098/rsob.210305] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Studies of the regulation of nucleolar function are critical for ascertaining clearer insights into the basic biological underpinnings of ribosome biogenesis (RB), and for future development of therapeutics to treat cancer and ribosomopathies. A number of high-throughput primary assays based on morphological alterations of the nucleolus can indirectly identify hits affecting RB. However, there is a need for a more direct high-throughput assay for a nucleolar function to further evaluate hits. Previous reports have monitored nucleolar rRNA biogenesis using 5-ethynyl uridine (5-EU) in low-throughput. We report a miniaturized, high-throughput 5-EU assay that enables specific calculation of nucleolar rRNA biogenesis inhibition, based on co-staining of the nucleolar protein fibrillarin (FBL). The assay uses two siRNA controls: a negative non-targeting siRNA control and a positive siRNA control targeting RNA Polymerase 1 (RNAP1; POLR1A), and specifically quantifies median 5-EU signal within nucleoli. Maximum nuclear 5-EU signal can also be used to monitor the effects of putative small-molecule inhibitors of RNAP1, like BMH-21, or other treatment conditions that cause FBL dispersion. We validate the 5-EU assay on 68 predominately nucleolar hits from a high-throughput primary screen, showing that 58/68 hits significantly inhibit nucleolar rRNA biogenesis. Our new method establishes direct quantification of nucleolar function in high-throughput, facilitating closer study of RB in health and disease.
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Affiliation(s)
- Carson J. Bryant
- Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, 333 Cedar Street, New Haven, CT, USA
| | - Mason A. McCool
- Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, 333 Cedar Street, New Haven, CT, USA
| | - Laura Abriola
- Yale Center for Molecular Discovery, Yale University, West Haven, CT, USA
| | | | - Susan J. Baserga
- Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, 333 Cedar Street, New Haven, CT, USA,Department of Genetics, Yale School of Medicine, New Haven, CT, USA,Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT, USA
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385
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Heinrich S, Hondele M. Probing Liquid-Liquid Phase Separation of RNA-Binding Proteins In Vitro and In Vivo. Methods Mol Biol 2022; 2537:307-333. [PMID: 35895272 DOI: 10.1007/978-1-0716-2521-7_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Biomolecular condensates and the concept of liquid-liquid phase separation (LLPS) have transformed cell biology in recent years. Condensates organize cellular content and compartmentalize biochemical reactions, in particular many processes involving RNA. This protocol is aimed at readers new to the LLPS field who want to test their protein or cellular structure of interest. We describe the basic principles of liquid-liquid phase separation, and outline initial approaches-both in vitro and in yeast cells-for the characterization of a candidate cellular condensate. First, we focus on strategies to purify phase-separating proteins and to reconstitute condensates from recombinant proteins in vitro for observation by light microscopy. Second, we describe in vivo experiments (including fluorescence recovery after photobleaching (FRAP) microscopy and 1,6-Hexanediol treatment) to test whether a subcellular structure displays liquid-like behavior in cells.
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Affiliation(s)
| | - Maria Hondele
- Biozentrum, University of Basel, Basel, Switzerland.
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386
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Abstract
This review covers research findings reported over the past decade concerning the ability of low complexity (LC) domains to self-associate in a manner leading to their phase separation from aqueous solution. We focus our message upon the reductionist use of two forms of phase separation as biochemical assays to study how LC domains might function in living cells. Cells and their varied compartments represent extreme examples of material condensates. Over the past half century, biochemists, structural biologists, and molecular biologists have resolved the mechanisms driving innumerable forms of macromolecular condensation. In contrast, we remain largely ignorant as to how 10%-20% of our proteins actually work to assist in cell organization. This enigmatic 10%-20% of the proteome corresponds to gibberish-like LC sequences. We contend that many of these LC sequences move in and out of a structurally ordered, self-associated state as a means of offering a combination of organizational specificity and dynamic pliability to living cells. Finally, we speculate that ancient proteins may have behaved similarly, helping to condense, organize, and protect RNA early during evolution.
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Affiliation(s)
- Masato Kato
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, Texas 75390, USA
- Institute for Quantum Life Science, National Institutes for Quantum and Radiological Science and Technology, Chiba 263-8555, Japan
| | - Xiaoming Zhou
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Steven L McKnight
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, Texas 75390, USA
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387
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Cockrell AJ, Gerton JL. Nucleolar Organizer Regions as Transcription-Based Scaffolds of Nucleolar Structure and Function. Results Probl Cell Differ 2022; 70:551-580. [PMID: 36348121 DOI: 10.1007/978-3-031-06573-6_19] [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] [Indexed: 06/16/2023]
Abstract
Eukaryotic genomes maintain multiple copies of ribosomal DNA gene repeats in tandem arrays to provide sufficient ribosomal RNAs to make ribosomes. These DNA repeats are the most highly transcribed regions of the genome, with dedicated transcriptional machinery to manage the enormous task of producing more than 50% of the total RNA in a proliferating cell. The arrays are called nucleolar organizer regions (NORs) and constitute the scaffold of the nucleolar compartment, where ribosome biogenesis occurs. Advances in molecular and cellular biology have brought great insights into how these arrays are transcribed and organized within genomes. Much of their biology is driven by their high transcription level, which has also driven the development of unique methods to understand rDNA gene activity, beginning with classic techniques such as silver staining and Miller spreads. However, the application of modern methodologies such as CRISPR gene editing, super-resolution microscopy, and long-read sequencing has enabled recent advances described herein, with many more discoveries possible soon. This chapter highlights what is known about NOR transcription and organization and the techniques applied historically and currently. Given the potential for NORs to impact organismal health and disease, as highlighted at the end of the chapter, the field must continue to develop and apply innovative analysis to understand genetic, epigenetic, and organizer properties of the ribosomal DNA repeats.
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Affiliation(s)
- Alexandria J Cockrell
- Stowers Institute for Medical Research, Kansas City, MO, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Jennifer L Gerton
- Stowers Institute for Medical Research, Kansas City, MO, USA.
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA.
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388
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Kasselimi E, Pefani DE, Taraviras S, Lygerou Z. Ribosomal DNA and the nucleolus at the heart of aging. Trends Biochem Sci 2022; 47:328-341. [DOI: 10.1016/j.tibs.2021.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 12/15/2022]
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389
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Petit FG, Jamin SP, Kernanec PY, Becker E, Halet G, Primig M. EXOSC10/Rrp6 is essential for the eight-cell embryo/morula transition. Dev Biol 2021; 483:58-65. [PMID: 34965385 DOI: 10.1016/j.ydbio.2021.12.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 12/16/2021] [Accepted: 12/21/2021] [Indexed: 11/03/2022]
Abstract
The conserved 3'-5' exoribonuclease EXOSC10/Rrp6 is required for gametogenesis, brain development, erythropoiesis and blood cell enhancer function. The human ortholog is essential for mitosis in cultured cancer cells. Little is known, however, about the role of Exosc10 during embryo development and organogenesis. We generated an Exosc10 knockout model and find that Exosc10-/- mice show an embryonic lethal phenotype. We demonstrate that Exosc10 maternal wild type mRNA is present in mutant oocytes and that the gene is expressed during all stages of early embryogenesis. Furthermore, we observe that EXOSC10 early on localizes to the periphery of nucleolus precursor bodies in blastomeres, which is in keeping with the protein's role in rRNA processing and may indicate a function in the establishment of chromatin domains during initial stages of embryogenesis. Finally, we infer from genotyping data for embryonic days e7.5, e6.5 and e4.5 and embryos cultured in vitro that Exosc10-/- mutants arrest at the eight-cell embryo/morula transition. Our results demonstrate a novel essential role for Exosc10 during early embryogenesis, and they are consistent with earlier work showing that impaired ribosome biogenesis causes a developmental arrest at the morula stage.
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Affiliation(s)
- Fabrice G Petit
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail), UMR_S 1085, F-35000, Rennes, France.
| | - Soazik P Jamin
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail), UMR_S 1085, F-35000, Rennes, France
| | - Pierre-Yves Kernanec
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail), UMR_S 1085, F-35000, Rennes, France
| | | | - Guillaume Halet
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes), UMR 6290, F-35000, Rennes, France
| | - Michael Primig
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail), UMR_S 1085, F-35000, Rennes, France.
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390
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Pluripotency transcription factors at the focus: the phase separation paradigm in stem cells. Biochem Soc Trans 2021; 49:2871-2878. [PMID: 34812855 DOI: 10.1042/bst20210856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/02/2021] [Accepted: 11/04/2021] [Indexed: 12/13/2022]
Abstract
The transcription factors (TFs) OCT4, SOX2 and NANOG are key players of the gene regulatory network of pluripotent stem cells. Evidence accumulated in recent years shows that even small imbalances in the expression levels or relative concentrations of these TFs affect both, the maintenance of pluripotency and cell fate decisions. In addition, many components of the transcriptional machinery including RNA polymerases, cofactors and TFs such as those required for pluripotency, do not distribute homogeneously in the nucleus but concentrate in multiple foci influencing the delivery of these molecules to their DNA-targets. How cells control strict levels of available pluripotency TFs in this heterogeneous space and the biological role of these foci remain elusive. In recent years, a wealth of evidence led to propose that many of the nuclear compartments are formed through a liquid-liquid phase separation process. This new paradigm early penetrated the stem cells field since many key players of the pluripotency circuitry seem to phase-separate. Overall, the formation of liquid compartments may modulate the kinetics of biochemical reactions and consequently regulate many nuclear processes. Here, we review the state-of-the-art knowledge of compartmentalization in the cell nucleus and the relevance of this process for transcriptional regulation, particularly in pluripotent stem cells. We also highlight the recent advances and new ideas in the field showing how compartmentalization may affect pluripotency preservation and cell fate decisions.
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391
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Sönmez A, Mustafa R, Ryll ST, Tuorto F, Wacheul L, Ponti D, Litke C, Hering T, Kojer K, Koch J, Pitzer C, Kirsch J, Neueder A, Kreiner G, Lafontaine DLJ, Orth M, Liss B, Parlato R. Nucleolar stress controls mutant Huntington toxicity and monitors Huntington's disease progression. Cell Death Dis 2021; 12:1139. [PMID: 34880223 PMCID: PMC8655027 DOI: 10.1038/s41419-021-04432-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 11/12/2021] [Accepted: 11/18/2021] [Indexed: 12/26/2022]
Abstract
Transcriptional and cellular-stress surveillance deficits are hallmarks of Huntington's disease (HD), a fatal autosomal-dominant neurodegenerative disorder caused by a pathological expansion of CAG repeats in the Huntingtin (HTT) gene. The nucleolus, a dynamic nuclear biomolecular condensate and the site of ribosomal RNA (rRNA) transcription, is implicated in the cellular stress response and in protein quality control. While the exact pathomechanisms of HD are still unclear, the impact of nucleolar dysfunction on HD pathophysiology in vivo remains elusive. Here we identified aberrant maturation of rRNA and decreased translational rate in association with human mutant Huntingtin (mHTT) expression. The protein nucleophosmin 1 (NPM1), important for nucleolar integrity and rRNA maturation, loses its prominent nucleolar localization. Genetic disruption of nucleolar integrity in vulnerable striatal neurons of the R6/2 HD mouse model decreases the distribution of mHTT in a disperse state in the nucleus, exacerbating motor deficits. We confirmed NPM1 delocalization in the gradually progressing zQ175 knock-in HD mouse model: in the striatum at a presymptomatic stage and in the skeletal muscle at an early symptomatic stage. In Huntington's patient skeletal muscle biopsies, we found a selective redistribution of NPM1, similar to that in the zQ175 model. Taken together, our study demonstrates that nucleolar integrity regulates the formation of mHTT inclusions in vivo, and identifies NPM1 as a novel, readily detectable peripheral histopathological marker of HD progression.
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Affiliation(s)
- Aynur Sönmez
- Institute of Applied Physiology, Ulm University, Ulm, Germany
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S./FNRS), Université Libre de Bruxelles (ULB), Biopark campus, Gosselies, Belgium
| | - Rasem Mustafa
- Institute of Applied Physiology, Ulm University, Ulm, Germany
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Salome T Ryll
- Institute of Applied Physiology, Ulm University, Ulm, Germany
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Francesca Tuorto
- Division of Biochemistry, Mannheim Institute for Innate Immunoscience (MI3), Medical Faculty Mannheim, Heidelberg University, Mannheim and Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Ludivine Wacheul
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S./FNRS), Université Libre de Bruxelles (ULB), Biopark campus, Gosselies, Belgium
| | - Donatella Ponti
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome "Sapienza", Rome, Italy
| | - Christian Litke
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Tanja Hering
- Department of Neurology, Ulm University, Ulm, Germany
| | - Kerstin Kojer
- Department of Neurology, Ulm University, Ulm, Germany
| | - Jenniver Koch
- Institute of Applied Physiology, Ulm University, Ulm, Germany
| | - Claudia Pitzer
- Interdisciplinary Neurobehavioral Core (INBC), Heidelberg University, Heidelberg, Germany
| | - Joachim Kirsch
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | | | - Grzegorz Kreiner
- Maj Institute of Pharmacology, Department of Brain Biochemistry, Polish Academy of Sciences, Krakow, Poland
| | - Denis L J Lafontaine
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S./FNRS), Université Libre de Bruxelles (ULB), Biopark campus, Gosselies, Belgium
| | - Michael Orth
- Department of Neurology, Ulm University, Ulm, Germany
| | - Birgit Liss
- Institute of Applied Physiology, Ulm University, Ulm, Germany
- Linacre & New College, University of Oxford, Oxford, UK
| | - Rosanna Parlato
- Institute of Applied Physiology, Ulm University, Ulm, Germany.
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany.
- Division for Neurodegenerative Diseases, Department of Neurology, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
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392
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Suzuki HI, Onimaru K. Biomolecular condensates in cancer biology. Cancer Sci 2021; 113:382-391. [PMID: 34865286 PMCID: PMC8819300 DOI: 10.1111/cas.15232] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 12/12/2022] Open
Abstract
Understanding the characteristics of cancer cells is essential for the development of improved diagnosis and therapeutics. From a gene regulation perspective, the super‐enhancer concept has been introduced to systematically understand the molecular mechanisms underlying the identities of various cell types and has been extended to the analysis of cancer cells and cancer genome alterations. In addition, several characteristic features of super‐enhancers have led to the recognition of the link between gene regulation and biomolecular condensates, which is often mediated by liquid‐liquid phase separation. Several lines of evidence have suggested molecular and biophysical principles and their alterations in cancer cells, which are particularly associated with gene regulation and cell signaling (“ transcriptional” and “signaling” condensates). These findings collectively suggest that the modification of biomolecular condensates represents an important mechanism by which cancer cells acquire various cancer hallmark traits and establish functional innovation for cancer initiation and progression. The condensate model also provides the molecular basis of the vulnerability of cancer cells to transcriptional perturbation and further suggests the possibility of therapeutic targeting of condensates. This review summarizes recent findings regarding the relationships between super‐enhancers and biomolecular condensate models, multiple scenarios of condensate alterations in cancers, and the potential of the condensate model for therapeutic development.
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Affiliation(s)
- Hiroshi I Suzuki
- Division of Molecular Oncology, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Institute for Glyco-core Research (iGCORE), Nagoya University, Nagoya, Japan
| | - Koh Onimaru
- Division of Molecular Oncology, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya, Japan.,RIKEN Center for Biosystems Dynamics Research, Wako, Japan
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393
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Phase Separation of Intrinsically Disordered Nucleolar Proteins Relate to Localization and Function. Int J Mol Sci 2021; 22:ijms222313095. [PMID: 34884901 PMCID: PMC8657925 DOI: 10.3390/ijms222313095] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/11/2021] [Accepted: 11/28/2021] [Indexed: 01/10/2023] Open
Abstract
The process of phase separation allows for the establishment and formation of subcompartmentalized structures, thus enabling cells to perform simultaneous processes with precise organization and low energy requirements. Chemical modifications of proteins, RNA, and lipids alter the molecular environment facilitating enzymatic reactions at higher concentrations in particular regions of the cell. In this review, we discuss the nucleolus as an example of the establishment, dynamics, and maintenance of a membraneless organelle with a high level of organization.
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394
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Abstract
Although long noncoding RNAs (lncRNAs) are generally expressed at low levels, emerging evidence has revealed that many play important roles in gene regulation by a variety of mechanisms as they engage with proteins. Given that the abundance of proteins often greatly exceeds that of their interacting lncRNAs, quantification of the relative abundance, or even the exact stoichiometry in some cases, within lncRNA-protein complexes is helpful for understanding of the mechanism(s) of action of lncRNAs. We discuss methods used to examine lncRNA and protein expression at the single cell, subcellular, and suborganelle levels, the average and local lncRNA concentration in cells, as well as how lncRNAs can modulate the functions of their interacting proteins even at a low stoichiometric concentration.
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Affiliation(s)
- Man Wu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Liang-Zhong Yang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ling-Ling Chen
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
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395
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Amar K, Wei F, Chen J, Wang N. Effects of forces on chromatin. APL Bioeng 2021; 5:041503. [PMID: 34661040 PMCID: PMC8516479 DOI: 10.1063/5.0065302] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 09/27/2021] [Indexed: 12/29/2022] Open
Abstract
Chromatin is a unique structure of DNA and histone proteins in the cell nucleus and the site of dynamic regulation of gene expression. Soluble factors are known to affect the chromatin structure and function via activating or inhibiting specific transcription factors. Forces on chromatin come from exogenous stresses on the cell surface and/or endogenous stresses, which are regulated by substrate mechanics, geometry, and topology. Forces on chromatin involve direct (via adhesion molecules, cytoskeleton, and the linker of nucleoskeleton and cytoskeleton complexes) and indirect (via diffusion and/or translocation processes) signaling pathways to modulate levels of chromatin folding and deformation to regulate transcription, which is controlled by histone modifications and depends on magnitude, direction, rate/frequency, duration, and modes of stresses. The rapid force transmission pathway activates multiple genes simultaneously, and the force may act like a "supertranscription factor." The indirect mechanotransduction pathways and the rapid force transmission pathway together exert sustained impacts on the chromatin, the nucleus, and cell functions.
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Affiliation(s)
- Kshitij Amar
- Department of Mechanical Science and Engineering, The Grainger College of Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Fuxiang Wei
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Junwei Chen
- Key Laboratory of Molecular Biophysics of the Ministry of Education, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Ning Wang
- Department of Mechanical Science and Engineering, The Grainger College of Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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396
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Abstract
Nuclear bodies are membraneless condensates that may form via liquid-liquid phase separation. The viscoelastic chromatin network could impact their stability and may hold the key for understanding experimental observations that defy predictions of classical theories. However, quantitative studies on the role of the chromatin network in phase separation have remained challenging. Using a diploid human genome model parameterized with chromosome conformation capture (Hi-C) data, we study the thermodynamics and kinetics of nucleoli formation. Dynamical simulations predict the formation of multiple droplets for nucleolar particles that experience specific interactions with nucleolus-associated domains (NADs). Coarsening dynamics, surface tension, and coalescence kinetics of the simulated droplets are all in quantitative agreement with experimental measurements for nucleoli. Free energy calculations further support that a two-droplet state, often observed for nucleoli in somatic cells, is metastable and separated from the single-droplet state with an entropic barrier. Our study suggests that nucleoli-chromatin interactions facilitate droplets' nucleation but hinder their coarsening due to the coupled motion between droplets and the chromatin network: as droplets coalesce, the chromatin network becomes increasingly constrained. Therefore, the chromatin network supports a nucleation and arrest mechanism to stabilize the multi-droplet state for nucleoli and possibly for other nuclear bodies.
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397
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Barros-Silva D, Klavert J, Jenster G, Jerónimo C, Lafontaine DLJ, Martens-Uzunova ES. The role of OncoSnoRNAs and Ribosomal RNA 2'-O-methylation in Cancer. RNA Biol 2021; 18:61-74. [PMID: 34775914 PMCID: PMC8677010 DOI: 10.1080/15476286.2021.1991167] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Ribosomes are essential nanomachines responsible for all protein production in cells. Ribosome biogenesis and function are energy costly processes, they are tightly regulated to match cellular needs. In cancer, major pathways that control ribosome biogenesis and function are often deregulated to ensure cell survival and to accommodate the continuous proliferation of tumour cells. Ribosomal RNAs (rRNAs) are abundantly modified with 2'-O-methylation (Nm, ribomethylation) being one of the most common modifications. In eukaryotic ribosomes, ribomethylation is performed by the methyltransferase Fibrillarin guided by box C/D small nucleolar RNAs (snoRNAs). Accumulating evidences indicate that snoRNA expression and ribosome methylation profiles are altered in cancer. Here we review our current knowledge on differential snoRNA expression and rRNA 2ʹ-O methylation in the context of human malignancies, and discuss the consequences and opportunities for cancer diagnostics, prognostics, and therapeutics.
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Affiliation(s)
- Daniela Barros-Silva
- Department of Urology, Erasmus MC Cancer Institute, University Medical Center, Rotterdam, The Netherlands.,Cancer Biology and Epigenetics Group, Research Center of IPO Porto (CI-IPOP) / RISE@CI-IPOP (Health Research Network), Portuguese Oncology Institute of Porto (IPO Porto) / Porto Comprehensive Cancer Center (Porto.CCC), Porto, Portugal
| | - Jonathan Klavert
- Department of Urology, Erasmus MC Cancer Institute, University Medical Center, Rotterdam, The Netherlands
| | - Guido Jenster
- Department of Urology, Erasmus MC Cancer Institute, University Medical Center, Rotterdam, The Netherlands
| | - Carmen Jerónimo
- Cancer Biology and Epigenetics Group, Research Center of IPO Porto (CI-IPOP) / RISE@CI-IPOP (Health Research Network), Portuguese Oncology Institute of Porto (IPO Porto) / Porto Comprehensive Cancer Center (Porto.CCC), Porto, Portugal.,Department of Pathology and Molecular Immunology, School of Medicine & Biomedical Sciences, University of Porto (Icbas-up), Porto, Portugal
| | - Denis L J Lafontaine
- Rna Molecular Biology, Fonds De La Recherche Scientifique (F.r.s./fnrs), Université Libre De Bruxelles (Ulb), BioPark Campus, Gosselies, Belgium
| | - Elena S Martens-Uzunova
- Department of Urology, Erasmus MC Cancer Institute, University Medical Center, Rotterdam, The Netherlands
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398
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Shen C, Li R, Negro R, Cheng J, Vora SM, Fu TM, Wang A, He K, Andreeva L, Gao P, Tian Z, Flavell RA, Zhu S, Wu H. Phase separation drives RNA virus-induced activation of the NLRP6 inflammasome. Cell 2021; 184:5759-5774.e20. [PMID: 34678144 DOI: 10.1016/j.cell.2021.09.032] [Citation(s) in RCA: 117] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 07/06/2021] [Accepted: 09/24/2021] [Indexed: 11/27/2022]
Abstract
NLRP6 is important in host defense by inducing functional outcomes including inflammasome activation and interferon production. Here, we show that NLRP6 undergoes liquid-liquid phase separation (LLPS) upon interaction with double-stranded RNA (dsRNA) in vitro and in cells, and an intrinsically disordered poly-lysine sequence (K350-354) of NLRP6 is important for multivalent interactions, phase separation, and inflammasome activation. Nlrp6-deficient or Nlrp6K350-354A mutant mice show reduced inflammasome activation upon mouse hepatitis virus or rotavirus infection, and in steady state stimulated by intestinal microbiota, implicating NLRP6 LLPS in anti-microbial immunity. Recruitment of ASC via helical assembly solidifies NLRP6 condensates, and ASC further recruits and activates caspase-1. Lipoteichoic acid, a known NLRP6 ligand, also promotes NLRP6 LLPS, and DHX15, a helicase in NLRP6-induced interferon signaling, co-forms condensates with NLRP6 and dsRNA. Thus, LLPS of NLRP6 is a common response to ligand stimulation, which serves to direct NLRP6 to distinct functional outcomes depending on the cellular context.
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Affiliation(s)
- Chen Shen
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Runzhi Li
- Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China; Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Roberto Negro
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; National Institute of Gastroenterology, "S. de Bellis" Research Hospital, Castellana Grotte, Bari 70013, Italy
| | - Jiewei Cheng
- Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China; Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Setu M Vora
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Tian-Min Fu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH 43210, USA; The Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA
| | - Anmin Wang
- Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China; Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Kaixin He
- Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China; Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Liudmila Andreeva
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Pu Gao
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhigang Tian
- Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China; Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Richard A Flavell
- Department of Immunobiology, Yale School of Medicine, New Haven, CT, USA; Howard Hughes Medical Institute, New Haven, CT, USA
| | - Shu Zhu
- Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China; Institute of Immunology, University of Science and Technology of China, Hefei, China.
| | - Hao Wu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA.
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399
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Yu H, Sun Z, Tan T, Pan H, Zhao J, Zhang L, Chen J, Lei A, Zhu Y, Chen L, Xu Y, Liu Y, Chen M, Sheng J, Xu Z, Qian P, Li C, Gao S, Daley GQ, Zhang J. rRNA biogenesis regulates mouse 2C-like state by 3D structure reorganization of peri-nucleolar heterochromatin. Nat Commun 2021; 12:6365. [PMID: 34753899 PMCID: PMC8578659 DOI: 10.1038/s41467-021-26576-2] [Citation(s) in RCA: 27] [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: 04/08/2021] [Accepted: 10/06/2021] [Indexed: 11/09/2022] Open
Abstract
The nucleolus is the organelle for ribosome biogenesis and sensing various types of stress. However, its role in regulating stem cell fate remains unclear. Here, we present evidence that nucleolar stress induced by interfering rRNA biogenesis can drive the 2-cell stage embryo-like (2C-like) program and induce an expanded 2C-like cell population in mouse embryonic stem (mES) cells. Mechanistically, nucleolar integrity maintains normal liquid-liquid phase separation (LLPS) of the nucleolus and the formation of peri-nucleolar heterochromatin (PNH). Upon defects in rRNA biogenesis, the natural state of nucleolus LLPS is disrupted, causing dissociation of the NCL/TRIM28 complex from PNH and changes in epigenetic state and reorganization of the 3D structure of PNH, which leads to release of Dux, a 2C program transcription factor, from PNH to activate a 2C-like program. Correspondingly, embryos with rRNA biogenesis defect are unable to develop from 2-cell (2C) to 4-cell embryos, with delayed repression of 2C/ERV genes and a transcriptome skewed toward earlier cleavage embryo signatures. Our results highlight that rRNA-mediated nucleolar integrity and 3D structure reshaping of the PNH compartment regulates the fate transition of mES cells to 2C-like cells, and that rRNA biogenesis is a critical regulator during the 2-cell to 4-cell transition of murine pre-implantation embryo development.
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Affiliation(s)
- Hua Yu
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Zhen Sun
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Tianyu Tan
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Hongru Pan
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Jing Zhao
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Ling Zhang
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Jiayu Chen
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Anhua Lei
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Yuqing Zhu
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Lang Chen
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Yuyan Xu
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China
| | - Yaxin Liu
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
| | - Ming Chen
- College of Life Sciences, Zhejiang University, 310058, Hangzhou, China
| | - Jinghao Sheng
- Institute of Environmental Medicine, and Cancer Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Zhengping Xu
- Institute of Environmental Medicine, and Cancer Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Pengxu Qian
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China
| | - Cheng Li
- Center for Bioinformatics, School of Life Sciences, Center for Statistical Science, Peking University, 100871, Beijing, China
| | - Shaorong Gao
- Clinical and Translational Research Center of Shanghai First Maternity and Infant Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - George Q Daley
- Stem Cell Transplantation Program, Division of Pediatric Hematology Oncology, Boston Children's Hospital, Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Jin Zhang
- Center of Stem Cell and Regenerative Medicine, Department of Basic Medical Sciences, and Bone Marrow Transplantation Center of the First Affiliated Hospital, Zhejiang University School of Medicine, 310003, Hangzhou, China.
- Zhejiang Laboratory for Systems & Precision Medicine, Zhejiang University Medical Center, 1369 West Wenyi Road, 311121, Hangzhou, China.
- Institute of Hematology, Zhejiang University, 310058, Hangzhou, China.
- Center of Gene/Cell Engineering and Genome Medicine, 310058, Hangzhou, Zhejiang, China.
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400
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Lee CH, Dermody TS. Some viruses need to phase-separate to replicate. EMBO J 2021; 40:e109558. [PMID: 34569635 DOI: 10.15252/embj.2021109558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 09/16/2021] [Indexed: 12/19/2022] Open
Abstract
Replication of rotavirus, an important cause of gastroenteritis in children, proceeds in large, easily discernible cytoplasmic structures, called viroplasms or viral factories, but mechanisms underlying their formation and function in infected cells have remained mysterious. In this issue, Geiger et al (2021) used a combination of in silico, in vitro, and cell-based approaches to define how two essential rotavirus nonstructural proteins, NSP2 and NSP5, form liquid-liquid phase-separated condensates as the structural foundation of rotavirus factories.
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Affiliation(s)
- Christopher H Lee
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Terence S Dermody
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Institute of Infection, Inflammation, and Immunity, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA.,Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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