Effects of Hyperthermia on Chromatin Condensation and Nucleoli

Total Page:16

File Type:pdf, Size:1020Kb

Effects of Hyperthermia on Chromatin Condensation and Nucleoli (CANCER RESEARCH 49, 1254-1260. March 1. 1989] Effects of Hyperthermia on Chromatin Condensation and Nucleoli Disintegration as Visualized by Induction of Premature Chromosome Condensation in Interphase Mammalian Cells1 George E. Iliakis and Gabriel E. Pantelias2 Thomas Jefferson University Hospital, Department of Radiation Oncology and Nuclear Medicine, Philadelphia, Pennsylvania 19107 [G. E. I., G. E. P.]; and the National Research Center for Physical Sciences "Demokritos", Aghia Paraskevi Attikis, Athens, Greece [G. E. P.] ABSTRACT nuclei (13), in chromatin (14-17), and in nuclear matrices (18, 19), and it was proposed that disruption of important nuclear The effects of hyperthermia on chromatin condensation and nucleoli processes by this nuclear protein binding may be the reason for disintegration, as visualized by induction of premature chromosome con cell killing (17). Beyond cell killing the excess nuclear proteins densation in interphase mammalian cells, was studied in exponentially have been implicated in the inhibition of DNA synthesis (5, 6) growing and plateau phase Chinese hamster ovary cells. Exposure to heat reduced the ability of interphase chromatin to condense and the and the inhibition of DNA repair following both ionizing (20, ability of the nucleolar organizing region to disintegrate under the influ 21) and uv (22) irradiation. It is thought that inhibition of ence of factors provided by mitotic cells when fused to interphase cells. these cellular functions may be due to alterations induced in Based on these effects treated cells were classified in three categories. chromatin conformation and in particular to restriction of DNA Category 1 contained cells able to condense their chromatin and disinte supercoiling changes as a result of protein addition to the grate the nucleolar organizing region. Category 2 contained cells able to nuclear matrix (19). These results stress the possible importance only partly condense their chromatin and unable to disintegrate the of chromatin as the principal site of heat-induced damage that nucleolar organizing region. Category 3 contained cells unable to condense ultimately leads to cell death. their chromatin and unable to disintegrate the nucleolar organizing region. Integrity and structural alterations in chromatin can also be The fraction of cells with nondisintegrated nucleoli increased with in studied by utilizing the technique of premature chromosome creasing exposure time at 45.5 < and reached a plateau at almost 100% condensation (23-26). Chromatin of a cell can ordinarily be after about 20 min. Exponentially growing and plateau phase cells showed similar response. Recovery from the effects of heat on chromatin conden visualized as distinct chromosomes only when the cell enters sation and disintegration of the nucleolar organizing region depended mitosis. However, when mitotic cells are fused with cells in upon the duration of the heat treatment. For exposures up to 15 min at interphase by means either of Sendai virus or of PEG,3 disin 45.5°C,agradual reduction in the fraction of cells with nondisintegrated tegration of the nuclear membrane and other nuclear structures nucleoli was observed when cells were allowed for repair at 37°C. takes place. In addition, interphase chromatin undergoes a However, only a very limited amount of repair was observed after a 30- min exposure to 45.5°C.The repair times observed at the chromosome condensation process taking morphology that is characteristic of the cell cycle phase of the interphase cell at the time of level were similar to those reported for the removal of excess protein fusion. This phenomenon is referred to as premature chromo accumulating in chromatin or the nuclear matrix, suggesting a causal some condensation (PCC) and the induced chromosome units relationship between the two phenomena. It is proposed that nuclear protein accumulation on chromatin or in the nuclear matrix reduces the as prematurely condensed chromosomes (also abbreviated as accessibility of chromatin to enzymes responsible for the phosphor) l:itinn PCC, the context clarifies the way in which the abbreviation is reactions necessary for chromatin condensation and disintegration of the used). The process of premature chromosome condensation can nucleolus. be thought of as a prophasing reaction (27). The factors from the mitotic cell responsible for the prophasing reaction are most likely heat and Ca2+ sensitive, Mg2+ dependent, proteins of INTRODUCTION relatively high molecular weight that bind preferentially to chromatin (28-33). The recent consideration of hyperthermia as an adjuvant to In this paper we report on the effects of heat (45.5 and 43°C) radiation therapy (1) and the possibility of probing mechanisms of gene expression using the synthesis of heat shock proteins on chromatin morphology and nuclear organization, as visual as a model system (2) has drawn much attention to the effects ized by PCC, in exponentially growing and plateau phase CHO of heat on living systems. To fully utilize the potential of cells. Selected results obtained with HeLa cells are also pre hyperthermia, or hyperthermia in conjunction with other mo sented and discussed. The results obtained indicate a dramatic dalities in the above-mentioned goals, it is necessary to deter effect of heat on the ability of chromatin to condense and on mine the molecular alterations that it induces as well as the the ability of the nucleolus to disintegrate after induction of lesions that lead to cell death. PCC. This is, to the best of our knowledge, the first report on Hyperthermia has been shown to induce a number of effects this topic. in mammalian cells including inhibition of DNA, RNA, and protein synthesis (3-6), induction of chromosomal aberrations MATERIALS AND METHODS (7, 8), and in ultrastructural studies, disappearance of the intranucleolar chromatin and the granular ribonucleoprotein Cell Culture and Heating. Experiments were performed using Chinese components of the nucleolus (9-12). Furthermore, hyperther hamster ovary cells, strain 10B, grown as monolayers in McCoy's 5A mia was found to increase the protein to DNA ratio in isolated medium supplemented with 10% fetal calf serum and antibiotics (50 units/ml potassium penicillin (i,, 50 Mg/ml streptomycin sulfate). Cells Received 8/22/88; revised 11/28/88; accepted 12/1/88. were grown at 37°Cina humidified incubator, in an atmosphere of 5% The costs of publication of this article were defrayed in part by the payment COj and 95% air. Stock cultures were maintained in vitro by routinely of page charges. This article must therefore be hereby marked advertisement in subculturing (every second day) at an initial density of 10'' cells in 75- accordance with 18 U.S.C. Section 1734 solely to indicate this fact. ' This work was supported in part by NCI Grants 1R01 CA45557 and 1R01 CA42026 awarded by the NIH. DHHS. 3The abbreviations used are: PEG, polyethylene glycol; PCC, premature 2Supported by Grant B16-E-206-GR awarded by the Commission of the chromosome condensation or prematurely condensed chromosome; CHO, European Communities, Radiation Protection Program. Chinese hamster ovary; PBS, phosphate buffered saline. 1254 Downloaded from cancerres.aacrjournals.org on September 26, 2021. © 1989 American Association for Cancer Research. EFFECTS OF HYPERTHERMIA ON INTERPHASE CHROMATIN cm2 tissue culture flasks. After 2 days of growth, cells in these cultures as required by the particular experimental protocol and processed for had reached a density of IO7per flask, and were used to prepare cultures fusion. Slides prepared were allowed to dry overnight at room temper for experiments. For this purpose, 10s cells, suspended in 3-ml growth ature and were subsequently immersed in photographic emulsion (II- medium, were plated in 25-cm2 tissue culture flasks and were allowed ford), after dilution with water (2:3, emulsion:water). Slides were dried to grow for 2 or 4 days in order to obtain exponentially growing or in a slight draft and placed in light tight boxes at 4°Cfor 2-5 days. plateau phase cells, respectively. Exponentially growing cultures had a After this period of time slides were developed and analyzed. density of 1-1.3 x IO6cells/flask and cultures in the plateau phase a density of 6-7 x IO6cells/flask. Flow cytometry measurements showed that exponentially growing cells contained about 45 ±5% cells in Gì RESULTS phase, 45 ±5% cells in S phase and 10 ±5% cells in G2 + M phase. In plateau phase cultures more than 90% (usually between 92 and 95%) Effect of Heat on the Process of Premature Chromosome of the cells were found at a stage in the cell cycle showing a DNA Condensation. Morphological changes induced by heat in chro- content equivalent to that of d cells, with the remaining cells found in matin and the chromosomes, as visualized in interphase cells S (3-5%) and in G2 (4-7%) phases. Cells were checked and found free using the technique of premature chromosome condensation, of mycoplasma contamination. To establish the general validity of the were investigated. Plateau phase cells were used first for these results obtained, experiments were also carried out with I lei .a cells experiments because they mainly contain Gìcells that show (kindly provided by Dr. Roti Roti, Washington University, St. Louis, complete chromatin condensation into discrete chromosomes MO). Cells were grown as monolayers in Joklik-modifled minimum after fusion with mitotic cells, thus simplifying analysis. How essential medium plus 3.5% each of fetal bovine and calf sera (16). ever, similar results were subsequently obtained with cells in Exponentially growing cultures were prepared by incubating for 2 days 3x10* cells in 5 ml of growth medium in 25-cm2 tissue culture flasks. every phase of the cycle (using exponentially growing cultures). Exponentially growing cells were heated in their growth medium Fig. 1 illustrates the chromosome condensation achieved after (pH 7.3-7.6) and plateau phase cells in fresh McCoy's 5A (without fusion and 1-h incubation at 37°C,of an untreated (nonheated) serum) to reduce pH related effects (pH of spent medium from plateau interphase (d) CHO cell with a cell at mitosis.
Recommended publications
  • PSF and P54nrb/Nono ^ Multi-Functional Nuclear Proteins
    FEBS 26628 FEBS Letters 531 (2002) 109^114 View metadata, citation and similar papers at core.ac.uk brought to you by CORE Minireview provided by Elsevier - Publisher Connector PSF and p54nrb/NonO ^ multi-functional nuclear proteins Yaron Shav-Tal, Dov Ziporià Department of Molecular Cell Biology, The Weizmann Institute of Science, Rehovot 76100, Israel Received 30 May 2002; revised 10 September 2002; accepted 11 September 2002 First published online 7 October 2002 Edited by Takashi Gojobori glutamine-rich N-terminus of PSF might be involved in pro- Abstract Proteins are often referred to in accordance with the activity with which they were ¢rst associated or the organelle in tein^protein interactions [2]. nrb which they were initially identi¢ed. However, a variety of nu- p54 (human) and NonO (mouse) are highly homologous clear factors act in multiple molecular reactions occurring si- to the C-terminus of PSF (Fig. 1) [7,8]. Proteomics have iden- multaneously within the nucleus. This review describes the func- ti¢ed PSF and p54nrb/NonO in the nucleolus [9] and in asso- tions of the nuclear factors PSF (polypyrimidine tract-binding ciation with the nuclear membrane [10]. p54nrb/NonO was protein-associated splicing factor) and p54nrb/NonO. PSF was recently shown to be a component of a novel nuclear domain initially termed a splicing factor due to its association with the termed paraspeckles [11].TheDrosophila homolog of these nrb second step of pre-mRNA splicing while p54 /NonO was proteins is the NONA/BJ6 protein encoded by the no-on-tran- thought to participate in transcriptional regulation.
    [Show full text]
  • Localization of Condensin Subunit XCAP-E in Interphase Nucleus, Nucleoid and Nuclear
    1 Localization of condensin subunit XCAP-E in interphase nucleus, nucleoid and nuclear matrix of XL2 cells. Elmira Timirbulatova, Igor Kireev, Vladimir Ju. Polyakov, and Rustem Uzbekov* Division of Electron Microscopy, A.N.Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119899, Moscow, Russia. *Author for correspondence: telephone. 007-095-939-55-28; FAX 007-095-939-31-81 e-mail: [email protected] Key words: XCAP-E; nucleolus; condensin; nuclear matrix; Xenopus. Abbreviations: DAPI , 4’, 6 diamidino-2-phenylindole; DNP, deoxyribonucleoprotein; DRB, 5,6-dichloro-1b-d-ribofuranosylbenzimidazole; SMC, structural maintenance of chromosomes; XCAP-E, Xenopus chromosome associated protein E. 2 Abstract The Xenopus XCAP-E protein is a component of condensin complex In the present work we investigate its localization in interphase XL2 cells and nucleoids. We shown, that XCAP-E is localizes in granular and in dense fibrillar component of nucleolus and also in small karyoplasmic structures (termed “SMC bodies”). Extraction by 2M NaCl does not influence XCAP-E distribution in nucleolus and “SMC bodies”. DNAse I treatment of interphase cells permeabilized by Triton X-100 or nucleoids resulted in partial decrease of labeling intensity in the nucleus, whereas RNAse A treatment resulted in practically complete loss of labeling of nucleolus and “SMC bodies” labeling. In mitotic cells, however, 2M NaCl extraction results in an intense staining of the chromosome region although the labeling was visible along the whole length of sister chromatids, with a stronger staining in centromore region. The data are discussed in view of a hypothesis about participation of XCAP-E in processing of ribosomal RNA.
    [Show full text]
  • Building the Interphase Nucleus: a Study on the Kinetics of 3D Chromosome Formation, Temporal Relation to Active Transcription, and the Role of Nuclear Rnas
    University of Massachusetts Medical School eScholarship@UMMS GSBS Dissertations and Theses Graduate School of Biomedical Sciences 2020-07-28 Building the Interphase Nucleus: A study on the kinetics of 3D chromosome formation, temporal relation to active transcription, and the role of nuclear RNAs Kristin N. Abramo University of Massachusetts Medical School Let us know how access to this document benefits ou.y Follow this and additional works at: https://escholarship.umassmed.edu/gsbs_diss Part of the Bioinformatics Commons, Cell Biology Commons, Computational Biology Commons, Genomics Commons, Laboratory and Basic Science Research Commons, Molecular Biology Commons, Molecular Genetics Commons, and the Systems Biology Commons Repository Citation Abramo KN. (2020). Building the Interphase Nucleus: A study on the kinetics of 3D chromosome formation, temporal relation to active transcription, and the role of nuclear RNAs. GSBS Dissertations and Theses. https://doi.org/10.13028/a9gd-gw44. Retrieved from https://escholarship.umassmed.edu/ gsbs_diss/1099 Creative Commons License This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License This material is brought to you by eScholarship@UMMS. It has been accepted for inclusion in GSBS Dissertations and Theses by an authorized administrator of eScholarship@UMMS. For more information, please contact [email protected]. BUILDING THE INTERPHASE NUCLEUS: A STUDY ON THE KINETICS OF 3D CHROMOSOME FORMATION, TEMPORAL RELATION TO ACTIVE TRANSCRIPTION, AND THE ROLE OF NUCLEAR RNAS A Dissertation Presented By KRISTIN N. ABRAMO Submitted to the Faculty of the University of Massachusetts Graduate School of Biomedical Sciences, Worcester in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSPOPHY July 28, 2020 Program in Systems Biology, Interdisciplinary Graduate Program BUILDING THE INTERPHASE NUCLEUS: A STUDY ON THE KINETICS OF 3D CHROMOSOME FORMATION, TEMPORAL RELATION TO ACTIVE TRANSCRIPTION, AND THE ROLE OF NUCLEAR RNAS A Dissertation Presented By KRISTIN N.
    [Show full text]
  • Nuclear Matrix
    Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective Pierre Cau, Claire Navarro, Karim Harhouri, Patrice Roll, Sabine Sigaudy, Elise Kaspi, Sophie Perrin, Annachiara de Sandre-Giovannoli, Nicolas Lévy To cite this version: Pierre Cau, Claire Navarro, Karim Harhouri, Patrice Roll, Sabine Sigaudy, et al.. Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective. Seminars in Cell and Developmental Biology, Elsevier, 2014, 29, pp.125-147. 10.1016/j.semcdb.2014.03.021. hal-01646524 HAL Id: hal-01646524 https://hal-amu.archives-ouvertes.fr/hal-01646524 Submitted on 20 Dec 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Review Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective Pierre Cau a,b,c,∗, Claire Navarro a,b,1, Karim Harhouri a,b,1, Patrice Roll a,b,c,1,2, Sabine Sigaudy a,b,d,1,3, Elise Kaspi a,b,c,1,2, Sophie Perrin a,b,1, Annachiara De Sandre-Giovannoli a,b,d,1,3, Nicolas Lévy a,b,d,∗∗ a Aix-Marseille
    [Show full text]
  • Nuclear Domains
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Cold Spring Harbor Laboratory Institutional Repository CELL SCIENCE AT A GLANCE 2891 Nuclear domains dynamic structures and, in addition, nuclear pore complex has been shown to rapid protein exchange occurs between have a remarkable substructure, in which David L. Spector many of the domains and the a basket extends into the nucleoplasm. Cold Spring Harbor Laboratory, One Bungtown nucleoplasm (Misteli, 2001). An The peripheral nuclear lamina lies Road, Cold Spring Harbor, NY 11724, USA extensive effort is currently underway by inside the nuclear envelope and is (e-mail: [email protected]) numerous laboratories to determine the composed of lamins A/C and B and is biological function(s) associated with thought to play a role in regulating Journal of Cell Science 114, 2891-2893 (2001) © The Company of Biologists Ltd each domain. The accompanying poster nuclear envelope structure and presents an overview of commonly anchoring interphase chromatin at the The mammalian cell nucleus is a observed nuclear domains. nuclear periphery. Internal patches of membrane-bound organelle that contains lamin protein are also present in the the machinery essential for gene The nucleus is bounded by a nuclear nucleoplasm (Moir et al., 2000). The expression. Although early studies envelope, a double-membrane structure, cartoon depicts much of the nuclear suggested that little organization exists of which the outer membrane is envelope/peripheral lamina as within this compartment, more contiguous with the rough endoplasmic transparent, so that internal structures contemporary studies have identified an reticulum and is often studded with can be more easily observed.
    [Show full text]
  • Association of DNA with Nuclear Matrix in in Vitro Assembled Nuclei
    Cell Research (1997), 7, 107-117 Association of DNA with nuclear matrix in in vitro as- sembled nuclei induced by rDNA from Tetrahymena shang- haiensis in Xenopus egg extracts CHEN YING, BO ZHANG, XIU FEN LI, ZHONG HE ZHAI Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing 100871 ABSTRACT The nuclei assembled from exogenous DNA or chro- matin in egg extracts resemble their in vivo counterparts in many aspects. However, the distribution pattern of DNA in these nuclei remains unknown. We introduced rDNA from the macronuclei of Tetrahymena into Xenopus cell- free extracts to examine the association of specific DNA sequences with nuclear matrix (NM) in the nuclei assem- bled in vitro. Our previous works showed the 5'NTS (non- transcription sequences) of the rDNA specifically bind to the NM system in the macronuclei. We show now the rDNA could induce chromatin assembly and nuclear for- mation in Xenopus cell-free system. When we extracted the NM system and compared the binding affinity of differ- ent regions of rDNA with the NM system, we found that the 5'NTS still hold their binding affinity with insoluble structure of the assembled nuclei in the extracts of Xeno- pus eggs. Key words: Nuclear assembly, nuclear matrix, Xeno- pus egg extracts, Tetrahymena rDNA. On the occasion of Professor Lu Ji SHI's (L. C. Sze), eightieth birthday, we present this paper and extend our sincere greetings to Professor SHI. As we mentioned in our paper, in early 1950's, it is Professor SHI who first studied the behavior of exogenous homologous desoxyribose nucleoprotein (chromatin) in amphibian eggs.
    [Show full text]
  • Nuclear Non-Chromatin Proteinaceous Structures: Their Role in the Organization and Function of the Interphase Nucleus
    J. Cell Set. 44, 395-435 (1980) 295 Printed in Great Britain © Company of BiologitU Limited igSo NUCLEAR NON-CHROMATIN PROTEINACEOUS STRUCTURES: THEIR ROLE IN THE ORGANIZATION AND FUNCTION OF THE INTERPHASE NUCLEUS PAUL S. AGUTTER* AND JONATHAN C. W. RICHARDSONf • Department of Biological Sciences, Napier College, Colinton Road, Edinburgh EH10 5DT, Scotland and f Department of Physiology and Pharmacology, University of St Andrews, Bute Medical Buildings, St Andrews, Fife, Scotland REVIEW ARTICLE: CONTENTS I. INTRODUCTION page 39s (1) Historical background 395 (2) Nomenclature 397 II. NUCLEAR PROTEIN MATRIX AND NUCLEAR GHOSTS 397 (1) Isolation 397 (2) Composition 398 (3) Ultrastructure 401 (4) Enzyme activities associated with the nuclear protein matrix 405 (5) Contractility of the nuclear protein matrix 405 (6) Functions associated with the nucleai protein matrix 408 III. SUBFRACTIONS OF THE NUCLEAR PROTEIN MATRIX 411 (A) The pore-lamina 411 (1) Isolation 411 (2) Composition 413 (3) Ultrastructure 414 (4) The molecular organization of the pore-lamina 417 (B) Other subfractions 419 IV. COMPOSITIONAL AND FUNCTIONAL DIFFERENCES BETWEEN THE PORE-LAMINA AND THE REMAINDER OF THE NUCLEAR PROTEIN MATRIX 42O V. PROSPECTS FOR FURTHER RESEARCH 422 (1) The role of the nuclear protein matrix in nucleo-cytoplasmic RNA transport 422 (2) Relevance of a knowledge of factors affecting the stability of the intra- nuclear regions of the matrix to the further development of methods for isolation of the nuclear envelope 423 (3) Fate of the nuclear matrix during mitosis 423 I. INTRODUCTION (1) Historical background Since 1949 there have been several accounts of a 'honeycomb layer' or 'nuclear cortex' in the nuclei of lower eukaryotes (Callan, Randall & Tomlin, 1949; Callan & Tomlin, 1950; Harris & James, 1952; Pappas, 1956; Beams, Tahmisian, Devine & 26-2 396 P.
    [Show full text]
  • Dynamic Force-Induced Direct Dissociation of Protein Complexes in a Nuclear Body in Living Cells
    ARTICLE Received 13 Jan 2012 | Accepted 26 Apr 2012 | Published 29 May 2012 DOI: 10.1038/ncomms1873 Dynamic force-induced direct dissociation of protein complexes in a nuclear body in living cells Yeh-Chuin Poh1, Sergey P. Shevtsov2, Farhan Chowdhury1, Douglas C. Wu1, Sungsoo Na3, Miroslav Dundr2 & Ning Wang1 Despite past progress in understanding mechanisms of cellular mechanotransduction, it is unclear whether a local surface force can directly alter nuclear functions without intermediate biochemical cascades. Here we show that a local dynamic force via integrins results in direct displacements of coilin and SMN proteins in Cajal bodies and direct dissociation of coilin-SMN associated complexes. Spontaneous movements of coilin increase more than those of SMN in the same Cajal body after dynamic force application. Fluorescence resonance energy transfer changes of coilin-SMN depend on force magnitude, an intact F-actin, cytoskeletal tension, Lamin A/C, or substrate rigidity. Other protein pairs in Cajal bodies exhibit different magnitudes of fluorescence resonance energy transfer. Dynamic cyclic force induces tiny phase lags between various protein pairs in Cajal bodies, suggesting viscoelastic interactions between them. These findings demonstrate that dynamic force-induced direct structural changes of protein complexes in Cajal bodies may represent a unique mechanism of mechanotransduction that impacts on nuclear functions involved in gene expression. 1 Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Champaign, Illinois 61801, USA. 2 Department of Cell Biology, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois 60064, USA. 3 Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indiana 46202, USA.
    [Show full text]
  • Nuclear Matrix Protein Matrin 3 Is a Regulator of ZAP-Mediated Retroviral
    Erazo and Goff. Retrovirology (2015) 12:57 DOI 10.1186/s12977-015-0182-4 RESEARCH Open Access Nuclear matrix protein Matrin 3 is a regulator of ZAP‑mediated retroviral restriction Angela Erazo1 and Stephen P Goff1,2* Abstract Background: Matrin 3 is a nuclear matrix protein involved in multiple nuclear processes. In HIV-1 infection, Matrin 3 serves as a Rev cofactor important for the cytoplasmic accumulation of HIV-1 transcripts. ZAP is a potent host restric- tion factor of multiple viruses including retroviruses HIV-1 and MoMuLV. In this study we sought to further character- ize Matrin 3 functions in the regulation of HIV gene expression. Results: Here we describe a function for Matrin 3 as a negative regulator of the ZAP-mediated restriction of retro- viruses. Mass spectrometry analysis of Matrin 3-associated proteins uncovered interactions with proteins of the ZAP degradation complex, DDX17 and EXOSC3. Coimmunoprecipitation studies confirmed Matrin 3 associations with DDX17, EXOSC3 and ZAP, in a largely RNA-dependent manner, indicating that RNA is mediating the Matrin 3 interac- tions with these components of the ZAP degradation complex. Silencing Matrin 3 expression caused a remarkably enhanced ZAP-driven inhibition of HIV-1 and MoMuLV luciferase reporter viruses. This effect was shared with addi- tional nuclear matrix proteins. ZAP targets multiply-spliced HIV-1 transcripts, but in the context of Matrin 3 suppres- sion, this ZAP restriction was broadened to unspliced and multiply-spliced RNAs. Conclusions: Here we reveal an unprecedented role for a nuclear matrix protein, Matrin 3, in the regulation of ZAP’s antiretroviral activity.
    [Show full text]
  • 1 the Nucleoporin ELYS Regulates Nuclear Size by Controlling NPC
    bioRxiv preprint doi: https://doi.org/10.1101/510230; this version posted January 2, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. The nucleoporin ELYS regulates nuclear size by controlling NPC number and nuclear import capacity Predrag Jevtić1,4, Andria C. Schibler2,4, Gianluca Pegoraro3, Tom Misteli2,*, Daniel L. Levy1,* 1 Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071 2 National Cancer Institute, NIH, Bethesda, MD, 20892 3 High Throughput Imaging Facility (HiTIF), National Cancer Institute, NIH, Bethesda, MD, 20892 4 Co-first authors *Corresponding authors: Daniel L. Levy Tom Misteli University of Wyoming National Cancer Institute, NIH Department of Molecular Biology Center for Cancer Research 1000 E. University Avenue 41 Library Drive, Bldg. 41, B610 Laramie, WY, 82071 Bethesda, MD, 20892 Phone: 307-766-4806 Phone: 240-760-6669 Fax: 307-766-5098 Fax: 301-496-4951 E-mail: [email protected] E-mail: [email protected] Running Head: ELYS is a nuclear size effector Abbreviations: NE, nuclear envelope; NPC, nuclear pore complex; ER, endoplasmic reticulum; Nup, nucleoporin; FG-Nup, phenylalanine-glycine repeat nucleoporin 1 bioRxiv preprint doi: https://doi.org/10.1101/510230; this version posted January 2, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license.
    [Show full text]
  • Direct Interaction Between Hnrnp-M and CDC5L/PLRG1 Proteins Affects Alternative Splice Site Choice
    Direct interaction between hnRNP-M and CDC5L/PLRG1 proteins affects alternative splice site choice David Llères, Marco Denegri, Marco Biggiogera, Paul Ajuh, Angus Lamond To cite this version: David Llères, Marco Denegri, Marco Biggiogera, Paul Ajuh, Angus Lamond. Direct interaction be- tween hnRNP-M and CDC5L/PLRG1 proteins affects alternative splice site choice. EMBO Reports, EMBO Press, 2010, 11 (6), pp.445 - 451. 10.1038/embor.2010.64. hal-03027049 HAL Id: hal-03027049 https://hal.archives-ouvertes.fr/hal-03027049 Submitted on 26 Nov 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. scientificscientificreport report Direct interaction between hnRNP-M and CDC5L/ PLRG1 proteins affects alternative splice site choice David Lle`res1*, Marco Denegri1*w,MarcoBiggiogera2,PaulAjuh1z & Angus I. Lamond1+ 1Wellcome Trust Centre for Gene Regulation & Expression, College of Life Sciences, University of Dundee, Dundee, UK, and 2LaboratoriodiBiologiaCellulareandCentrodiStudioperl’IstochimicadelCNR,DipartimentodiBiologiaAnimale, Universita’ di Pavia, Pavia, Italy Heterogeneous nuclear ribonucleoprotein-M (hnRNP-M) is an and affect the fate of heterogeneous nuclear RNAs by influencing their abundant nuclear protein that binds to pre-mRNA and is a structure and/or by facilitating or hindering the interaction of their component of the spliceosome complex.
    [Show full text]
  • Snapshot: Cellular Bodies David L
    SnapShot: Cellular Bodies David L. Spector Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA Number/ Typical Size Marker Body Name Description Image Cell and Shape Protein Involved in snRNP and snoRNP biogenesis and 0.1–2.0 µm; Cajal Body 0–6 Coilin posttranscriptional modification of newly assembled round spliceosomal snRNAs. 20S core Contains ubiquitin conjugates, the proteolytically active 0.2–1.2 µm; catalytic Clastosome 0–3 20S core and 19S regulatory complexes of the 26S irregular component of proteasome, and protein substrates of the proteasome. proteasome Contains several factors involved in 3′ cleavage of mRNAs. 0.2–1.0 µm; Cleavage Body 1–4 CstF 64 kDa ?20% contain newly synthesized RNA. Some cleavage round bodies localize adjacent to Cajal and PML bodies. Nuclear Contains proteins for pre-mRNA processing. Involved in Speckle or 0.8–1.8 µm; SC35, 25–50 the storage, assembly, and/or modification of pre-mRNA Interchromatin irregular SF2/ASF splicing factors. Granule Cluster Induced by heat shock response. Associates with Nuclear Stress 0.3–3.0 µm; satellite III repeats on human chromosome 9q12 and 2–10 HSF1 Body irregular other pericentromeric regions; recruits various RNA- binding proteins. Contains several transcription factors (Oct1/PTF) and 1.0–1.5 µm; OPT Domain 1–3 PTF RNA transcripts; predominant in late G1 cells. Often round Nuclear Bodies localizes close to nucleolus. 0.5 µm; Contains several RNA-binding proteins and nuclear- Paraspeckle 10–20 p54nrb, PSP1 round retained CTN-RNA. Cap on surface of nucleolus; found mainly in transformed Perinucleolar 0.3–1.0 µm; 1–4 hnRNPI (PTB) cells.
    [Show full text]