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Brand CL, Oliver GT, Farkas IZ, Buszczak M, Levine MT. Recurrent Duplication and Diversification of a Vital DNA Repair Gene Family Across Drosophila. Mol Biol Evol 2024; 41:msae113. [PMID: 38865490 PMCID: PMC11210505 DOI: 10.1093/molbev/msae113] [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: 11/07/2023] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/14/2024] Open
Abstract
Maintaining genome integrity is vital for organismal survival and reproduction. Essential, broadly conserved DNA repair pathways actively preserve genome integrity. However, many DNA repair proteins evolve adaptively. Ecological forces like UV exposure are classically cited drivers of DNA repair evolution. Intrinsic forces like repetitive DNA, which also imperil genome integrity, have received less attention. We recently reported that a Drosophila melanogaster-specific DNA satellite array triggered species-specific, adaptive evolution of a DNA repair protein called Spartan/MH. The Spartan family of proteases cleave hazardous, covalent crosslinks that form between DNA and proteins ("DNA-protein crosslink repair"). Appreciating that DNA satellites are both ubiquitous and universally fast-evolving, we hypothesized that satellite DNA turnover spurs adaptive evolution of DNA-protein crosslink repair beyond a single gene and beyond the D. melanogaster lineage. This hypothesis predicts pervasive Spartan gene family diversification across Drosophila species. To study the evolutionary history of the Drosophila Spartan gene family, we conducted population genetic, molecular evolution, phylogenomic, and tissue-specific expression analyses. We uncovered widespread signals of positive selection across multiple Spartan family genes and across multiple evolutionary timescales. We also detected recurrent Spartan family gene duplication, divergence, and gene loss. Finally, we found that ovary-enriched parent genes consistently birthed functionally diverged, testis-enriched daughter genes. To account for Spartan family diversification, we introduce a novel mechanistic model of antagonistic coevolution that links DNA satellite evolution and adaptive regulation of Spartan protease activity. This framework promises to accelerate our understanding of how DNA repeats drive recurrent evolutionary innovation to preserve genome integrity.
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Affiliation(s)
- Cara L Brand
- Department of Biology and Epigenetics Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Genevieve T Oliver
- Department of Biology and Epigenetics Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Isabella Z Farkas
- Department of Biology and Epigenetics Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael Buszczak
- Department of Molecular Biology and Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Mia T Levine
- Department of Biology and Epigenetics Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
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2
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Córdova-Oriz I, Polonio AM, Cuadrado-Torroglosa I, Chico-Sordo L, Medrano M, García-Velasco JA, Varela E. Chromosome ends and the theory of marginotomy: implications for reproduction. Biogerontology 2024; 25:227-248. [PMID: 37943366 DOI: 10.1007/s10522-023-10071-w] [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: 07/26/2023] [Accepted: 09/21/2023] [Indexed: 11/10/2023]
Abstract
Telomeres are the protective structures located at the ends of linear chromosomes. They were first described in the 1930s, but their biology remained unexplored until the early 70s, when Alexey M. Olovnikov, a theoretical biologist, suggested that telomeres cannot be fully copied during DNA replication. He proposed a theory that linked this phenomenon with the limit of cell proliferation capacity and the "duration of life" (theory of marginotomy), and suggested a potential of telomere lenghthening for the prevention of aging (anti-marginotomy). The impact of proliferative telomere shortening on life expectancy was later confirmed. In humans, telomere shortening is counteracted by telomerase, an enzyme that is undetectable in most adult somatic cells, but present in cancer cells and adult and embryonic stem and germ cells. Although telomere length dynamics are different in male and female gametes during gametogenesis, telomere lengths are reset at the blastocyst stage, setting the initial length of the species. The role of the telomere pathway in reproduction has been explored for years, mainly because of increased infertility resulting from delayed childbearing. Short telomere length in ovarian somatic cells is associated to decreased fertility and higher aneuploidy rates in embryos. Consequently, there is a growing interest in telomere lengthening strategies, aimed at improving fertility. It has also been observed that lifestyle factors can affect telomere length and improve fertility outcomes. In this review, we discuss the implications of telomere theory in fertility, especially in oocytes, spermatozoa, and embryos, as well as therapies to enhance reproductive success.
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Affiliation(s)
- Isabel Córdova-Oriz
- IVIRMA Global Research Alliance, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Valencia, Spain
| | - Alba M Polonio
- IVIRMA Global Research Alliance, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Valencia, Spain
| | - Isabel Cuadrado-Torroglosa
- IVIRMA Global Research Alliance, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Valencia, Spain
| | - Lucía Chico-Sordo
- IVIRMA Global Research Alliance, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Valencia, Spain
| | - Marta Medrano
- IVIRMA Global Research Alliance, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Valencia, Spain
| | - Juan A García-Velasco
- IVIRMA Global Research Alliance, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Valencia, Spain
- IVIRMA Global Research Alliance, IVIRMA Madrid, Madrid, Spain
- Department of Medical Specialties and Public Health, Edificio Departamental II, Rey Juan Carlos University, Av. de Atenas, s/n, 28922, Alcorcón, Madrid, Spain
| | - Elisa Varela
- IVIRMA Global Research Alliance, Instituto de Investigación Sanitaria La Fe (IIS La Fe), Valencia, Spain.
- Department of Medical Specialties and Public Health, Edificio Departamental II, Rey Juan Carlos University, Av. de Atenas, s/n, 28922, Alcorcón, Madrid, Spain.
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3
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Das A, Giri AK, Bhattacharjee P. Targeting 'histone mark': Advanced approaches in epigenetic regulation of telomere dynamics in cancer. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:195007. [PMID: 38237857 DOI: 10.1016/j.bbagrm.2024.195007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 01/23/2024]
Abstract
Telomere integrity is required for the maintenance of genome stability and prevention of oncogenic transformation of cells. Recent evidence suggests the presence of epigenetic modifications as an important regulator of mammalian telomeres. Telomeric and subtelomeric regions are rich in epigenetic marks that regulate telomere length majorly through DNA methylation and post-translational histone modifications. Specific histone modifying enzymes play an integral role in establishing telomeric histone codes necessary for the maintenance of structural integrity. Alterations of crucial histone moieties and histone modifiers cause deregulations in the telomeric chromatin leading to carcinogenic manifestations. This review delves into the significance of histone modifications and their influence on telomere dynamics concerning cancer. Additionally, it highlights the existing research gaps that hold the potential to drive the development of therapeutic interventions targeting the telomere epigenome.
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Affiliation(s)
- Ankita Das
- Department of Environmental Science, University of Calcutta, Kolkata 700019, India; Department of Zoology, University of Calcutta, Kolkata 700019, India
| | - Ashok K Giri
- Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India
| | - Pritha Bhattacharjee
- Department of Environmental Science, University of Calcutta, Kolkata 700019, India.
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Xu Y, Komiyama M. G-Quadruplexes in Human Telomere: Structures, Properties, and Applications. Molecules 2023; 29:174. [PMID: 38202757 PMCID: PMC10780218 DOI: 10.3390/molecules29010174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/20/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024] Open
Abstract
G-quadruplexes, intricate four-stranded structures composed of G-tetrads formed by four guanine bases, are prevalent in both DNA and RNA. Notably, these structures play pivotal roles in human telomeres, contributing to essential cellular functions. Additionally, the existence of DNA:RNA hybrid G-quadruplexes adds a layer of complexity to their structural diversity. This review provides a comprehensive overview of recent advancements in unraveling the intricacies of DNA and RNA G-quadruplexes within human telomeres. Detailed insights into their structural features are presented, encompassing the latest developments in chemical approaches designed to probe these G-quadruplex structures. Furthermore, this review explores the applications of G-quadruplex structures in targeting human telomeres. Finally, the manuscript outlines the imminent challenges in this evolving field, setting the stage for future investigations.
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Affiliation(s)
- Yan Xu
- Division of Chemistry, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan
| | - Makoto Komiyama
- Research Center for Advanced Science and Technology (RCAST), The University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8904, Japan
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Abstract
Keratinocyte senescence contributes to skin ageing and epidermal dysfunction. According to the existing knowledge, the transcription factor ΔNp63α plays pivotal roles in differentiation and proliferation of keratinocytes. It is traditionally accepted that ΔNp63α exerts its functions via binding to promoter regions to activate or repress gene transcription. However, accumulating evidence demonstrates that ΔNp63α can bind to elements away from promoter regions of its target genes, mediating epigenetic regulation. On the other hand, several epigenetic alterations, including DNA methylation, histone modification and variation, chromatin remodelling, as well as enhancer-promoter looping, are found to be related to cell senescence. To systematically elucidate how ΔNp63α affects keratinocyte senescence via epigenetic regulation, we comprehensively compiled the literatures on the roles of ΔNp63α in keratinocyte senescence, epigenetics in cellular senescence, and the relation between ΔNp63α-mediated epigenetic regulation and keratinocyte senescence. Based on the published data, we conclude that ΔNp63α mediates epigenetic regulation via multiple mechanisms: recruiting epigenetic enzymes to modify DNA or histones, coordinating chromatin remodelling complexes (CRCs) or regulating their expression, and mediating enhancer-promoter looping. Consequently, the expression of genes related to cell cycle is modulated, and proliferation of keratinocytes and renewal of stem cells are maintained, by ΔNp63α. During skin inflammaging, the decline of ΔNp63α may lead to epigenetic dysregulation, resultantly deteriorating keratinocyte senescence.
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Affiliation(s)
- Linghan Kuang
- Department of Laboratory Medicine, West China Second University Hospital, Sichuan University, Chengdu 610041, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu 610041, China
| | - Chenghua Li
- Center of Growth, Metabolism and Aging, Key Laboratory of Biological Resources and Ecological Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, China
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Sze S, Bhardwaj A, Fnu P, Azarm K, Mund R, Ring K, Smith S. TERRA R-loops connect and protect sister telomeres in mitosis. Cell Rep 2023; 42:113235. [PMID: 37843976 PMCID: PMC10873023 DOI: 10.1016/j.celrep.2023.113235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/08/2023] [Accepted: 09/22/2023] [Indexed: 10/18/2023] Open
Abstract
Resolution of cohesion between sister telomeres in human cells depends on TRF1-mediated recruitment of the polyADP-ribosyltransferase tankyrase to telomeres. In human aged cells, due to insufficient recruitment of TRF1/tankyrase to shortened telomeres, sisters remain cohered in mitosis. This persistent cohesion plays a protective role, but the mechanism by which sisters remain cohered is not well understood. Here we show that telomere repeat-containing RNA (TERRA) holds sister telomeres together through RNA-DNA hybrid (R-loop) structures. We show that a tankyrase-interacting partner, the RNA-binding protein C19orf43, is required for repression of TERRA R-loops. Persistent telomere cohesion in C19orf43-depleted cells is counteracted by RNaseH1, confirming that RNA-DNA hybrids hold sisters together. Consistent with a protective role for persistent telomere cohesion, depletion of C19orf43 in aged cells reduces DNA damage and delays replicative senescence. We propose that the inherent inability of shortened telomeres to recruit R-loop-repressing machinery permits a controlled onset of senescence.
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Affiliation(s)
- Samantha Sze
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016, USA
| | | | - Priyanka Fnu
- University of Rochester Medical Center, Rochester, NY 14642, USA
| | | | - Rachel Mund
- New York Medical College, Valhalla, NY 10595, USA
| | - Katherine Ring
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016, USA
| | - Susan Smith
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016, USA.
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Stylianakis E, Chan JPK, Law PP, Jiang Y, Khadayate S, Karimi MM, Festenstein R, Vannier JB. Mouse HP1γ regulates TRF1 expression and telomere stability. Life Sci 2023; 331:122030. [PMID: 37598977 DOI: 10.1016/j.lfs.2023.122030] [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: 11/29/2022] [Revised: 08/16/2023] [Accepted: 08/17/2023] [Indexed: 08/22/2023]
Abstract
AIMS Telomeric repeat-containing RNAs are long non-coding RNAs generated from the telomeres. TERRAs are essential for the establishment of heterochromatin marks at telomeres, which serve for the binding of members of the heterochromatin protein 1 (HP1) protein family of epigenetic modifiers involved with chromatin compaction and gene silencing. While HP1γ is enriched on gene bodies of actively transcribed human and mouse genes, it is unclear if its transcriptional role is important for HP1γ function in telomere cohesion and telomere maintenance. We aimed to study the effect of mouse HP1γ on the transcription of telomere factors and molecules that can affect telomere maintenance. MAIN METHODS We investigated the telomere function of HP1γ by using HP1γ deficient mouse embryonic fibroblasts (MEFs). We used gene expression analysis of HP1γ deficient MEFs and validated the molecular and mechanistic consequences of HP1γ loss by telomere FISH, immunofluorescence, RT-qPCR and DNA-RNA immunoprecipitation (DRIP). KEY FINDINGS Loss of HP1γ in primary MEFs led to a downregulation of various telomere and telomere-accessory transcripts, including the shelterin protein TRF1. Its downregulation is associated with increased telomere replication stress and DNA damage (γH2AX), effects more profound in females. We suggest that the source for the impaired telomere maintenance is a consequence of increased telomeric DNA-RNA hybrids and TERRAs arising at and from mouse chromosomes 18 and X. SIGNIFICANCE Our results suggest an important transcriptional control by mouse HP1γ of various telomere factors including TRF1 protein and TERRAs that has profound consequences on telomere stability, with a potential sexually dimorphic nature.
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Affiliation(s)
- Emmanouil Stylianakis
- Telomere Replication & Stability group, Medical Research Council London Institute of Medical Sciences, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom; Gene Control Mechanisms and Disease Group, Faculty of Medicine, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Jackson Ping Kei Chan
- Gene Control Mechanisms and Disease Group, Faculty of Medicine, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Pui Pik Law
- Gene Control Mechanisms and Disease Group, Faculty of Medicine, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Yi Jiang
- Gene Control Mechanisms and Disease Group, Faculty of Medicine, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Sanjay Khadayate
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Mohammad Mahdi Karimi
- Comprehensive Cancer Centre, School of Cancer & Pharmaceutical Sciences, Faculty of Life Sciences & Medicine, King's College London, London, United Kingdom
| | - Richard Festenstein
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom; Gene Control Mechanisms and Disease Group, Faculty of Medicine, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Jean-Baptiste Vannier
- Telomere Replication & Stability group, Medical Research Council London Institute of Medical Sciences, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom.
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8
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Liu J, Zheng T, Chen D, Huang J, Zhao Y, Ma W, Liu H. RBMX involves in telomere stability maintenance by regulating TERRA expression. PLoS Genet 2023; 19:e1010937. [PMID: 37756323 PMCID: PMC10529574 DOI: 10.1371/journal.pgen.1010937] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 08/23/2023] [Indexed: 09/29/2023] Open
Abstract
Telomeric repeat-containing RNA (TERRA) is a class of long noncoding RNAs (lncRNAs) that are transcribed from subtelomeric to telomeric region of chromosome ends. TERRA is prone to form R-loop structures at telomeres by invading into telomeric DNA. Excessive telomere R-loops result in telomere instability, so the TERRA level needs to be delicately modulated. However, the molecular mechanisms and factors controlling TERRA level are still largely unknown. In this study, we report that the RNA binding protein RBMX is a novel regulator of TERRA level and telomere integrity. The expression level of TERRA is significantly elevated in RBMX depleted cells, leading to enhanced telomere R-loop formation, replication stress, and telomere instability. We also found that RBMX binds to TERRA and the nuclear exosome targeting protein ZCCHC8 simultaneously, and that TERRA degradation slows down upon RBMX depletion, implying that RBMX promotes TERRA degradation by regulating its transportation to the nuclear exosome, which decays nuclear RNAs. Altogether, these findings uncover a new role of RBMX in TERRA expression regulation and telomere integrity maintenance, and raising RBMX as a potential target of cancer therapy.
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Affiliation(s)
- Jingfan Liu
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Tian Zheng
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People’s Republic of China
| | - Dandan Chen
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Junjiu Huang
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Yong Zhao
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Wenbin Ma
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Haiying Liu
- MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China
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Agredo A, Kasinski AL. Histone 4 lysine 20 tri-methylation: a key epigenetic regulator in chromatin structure and disease. Front Genet 2023; 14:1243395. [PMID: 37671044 PMCID: PMC10475950 DOI: 10.3389/fgene.2023.1243395] [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: 06/20/2023] [Accepted: 08/07/2023] [Indexed: 09/07/2023] Open
Abstract
Chromatin is a vital and dynamic structure that is carefully regulated to maintain proper cell homeostasis. A great deal of this regulation is dependent on histone proteins which have the ability to be dynamically modified on their tails via various post-translational modifications (PTMs). While multiple histone PTMs are studied and often work in concert to facilitate gene expression, here we focus on the tri-methylation of histone H4 on lysine 20 (H4K20me3) and its function in chromatin structure, cell cycle, DNA repair, and development. The recent studies evaluated in this review have shed light on how H4K20me3 is established and regulated by various interacting partners and how H4K20me3 and the proteins that interact with this PTM are involved in various diseases. Through analyzing the current literature on H4K20me3 function and regulation, we aim to summarize this knowledge and highlights gaps that remain in the field.
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Affiliation(s)
- Alejandra Agredo
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
- Purdue Life Sciences Interdisciplinary Program (PULSe), Purdue University, West Lafayette, IN, United States
| | - Andrea L. Kasinski
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
- Purdue Institute for Cancer Research, Purdue University, West Lafayette, IN, United States
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10
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Takeuchi C, Yokoshi M, Kondo S, Shibuya A, Saito K, Fukaya T, Siomi H, Iwasaki Y. Mod(mdg4) variants repress telomeric retrotransposon HeT-A by blocking subtelomeric enhancers. Nucleic Acids Res 2022; 50:11580-11599. [PMID: 36373634 PMCID: PMC9723646 DOI: 10.1093/nar/gkac1034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/17/2022] [Accepted: 10/22/2022] [Indexed: 11/16/2022] Open
Abstract
Telomeres in Drosophila are composed of sequential non-LTR retrotransposons HeT-A, TART and TAHRE. Although they are repressed by the PIWI-piRNA pathway or heterochromatin in the germline, the regulation of these retrotransposons in somatic cells is poorly understood. In this study, we demonstrated that specific splice variants of Mod(mdg4) repress HeT-A by blocking subtelomeric enhancers in ovarian somatic cells. Among the variants, we found that the Mod(mdg4)-N variant represses HeT-A expression the most efficiently. Subtelomeric sequences bound by Mod(mdg4)-N block enhancer activity within subtelomeric TAS-R repeats. This enhancer-blocking activity is increased by the tandem association of Mod(mdg4)-N to repetitive subtelomeric sequences. In addition, the association of Mod(mdg4)-N couples with the recruitment of RNA polymerase II to the subtelomeres, which reinforces its enhancer-blocking function. Our findings provide novel insights into how telomeric retrotransposons are regulated by the specific variants of insulator proteins associated with subtelomeric sequences.
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Affiliation(s)
- Chikara Takeuchi
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Moe Yokoshi
- Laboratory of Transcription Dynamics, Research Center for Biological Visualization, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo 113-0032, Japan
| | - Shu Kondo
- Department of Chromosome Science, National Institute of Genetics, Research Organization of Information and Systems (ROIS), Shizuoka 411-8540, Japan
| | - Aoi Shibuya
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Kuniaki Saito
- Department of Chromosome Science, National Institute of Genetics, Research Organization of Information and Systems (ROIS), Shizuoka 411-8540, Japan
| | - Takashi Fukaya
- Laboratory of Transcription Dynamics, Research Center for Biological Visualization, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo 113-0032, Japan,Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 113-0032, Japan
| | | | - Yuka W Iwasaki
- To whom correspondence should be addressed. Tel: +81 3 5363 3529; Fax: +81 3 5363 3266;
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Mishra R, Haldar S, Biondi S, Bhari VK, Singh G, Bhowmick NA. TGF-β controls stromal telomere length through epigenetic modifications. 3 Biotech 2022; 12:290. [PMID: 36276465 PMCID: PMC9512944 DOI: 10.1007/s13205-022-03346-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 09/01/2022] [Indexed: 11/01/2022] Open
Abstract
Telomere length is primarily controlled by the enzyme telomerase, but being chromatin structures, telomeres undergo epigenetic regulation for their maintenance and function. Altered telomere length among cancer cells combined with shorter telomere length in cancer-associated stromal cells, strongly implicated with progression to prostate cancer metastasis and cancer death and providing a novel target for therapeutics. Transforming growth factor-β (TGF-β) signaling pathways are well-recognized for their role in stromal-epithelial interactions responsible for prostate androgen responsiveness, promoting tumorigenesis. However, the underlying mechanism remains unclear. We sought to establish a role for TGF-β in the regulation of telomere length in mouse and human prostate fibroblast. Polymerase chain reaction (PCR)-based telomere length measuring methods are widely used due to their repeatability and reproducibility. Using real-time RT-PCR-based telomere length measuring method, we identified that TGF-beta regulates telomere length via increased expression of histone methyltransferase, Suv39h1, which in turn affected histone methylation levels at the telomeric ends. Moreover, treatment of DAPT and non-steroidal antiandrogen bicalutamide demonstrated that notch and androgen signaling co-operated with TGF-ß in regulating stromal telomere length. Telomere variation in tumor cells and non-tumor cells within the tumor microenvironment greatly facilitates the clinical assessment of prostate cancer; therefore, understanding stromal telomere length regulation mechanism will hold significant prospects for cancer treatment, diagnosis, and prognosis. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-022-03346-5.
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Affiliation(s)
- Rajeev Mishra
- Department of Life Sciences and Biotechnology, Chhatrapati Shahu Ji Maharaj University, Kalyanpur, Kanpur, UP 208024 India
- Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA
| | - Subhash Haldar
- Department of Food and Nutrition, University of Gour Banga, Mokdumpur, West Bengal 732101 India
| | - Shea Biondi
- Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA
| | - Vikash Kumar Bhari
- Department of Biosciences, Manipal University Jaipur, Jaipur, Rajasthan 303007 India
| | - Gyanendra Singh
- Toxicology Department, ICMR-National Institute of Occupational Health, Ahmedabad, 380016 India
| | - Neil A Bhowmick
- Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048 USA
- Department of Research, Greater Los Angeles Veterans Administration, Los Angeles, CA 90073 USA
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Cross-species incompatibility between a DNA satellite and the Drosophila Spartan homolog poisons germline genome integrity. Curr Biol 2022; 32:2962-2971.e4. [DOI: 10.1016/j.cub.2022.05.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 04/06/2022] [Accepted: 05/05/2022] [Indexed: 12/19/2022]
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13
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Vourc’h C, Dufour S, Timcheva K, Seigneurin-Berny D, Verdel A. HSF1-Activated Non-Coding Stress Response: Satellite lncRNAs and Beyond, an Emerging Story with a Complex Scenario. Genes (Basel) 2022; 13:genes13040597. [PMID: 35456403 PMCID: PMC9032817 DOI: 10.3390/genes13040597] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/18/2022] [Accepted: 03/19/2022] [Indexed: 12/21/2022] Open
Abstract
In eukaryotes, the heat shock response is orchestrated by a transcription factor named Heat Shock Factor 1 (HSF1). HSF1 is mostly characterized for its role in activating the expression of a repertoire of protein-coding genes, including the heat shock protein (HSP) genes. Remarkably, a growing set of reports indicate that, upon heat shock, HSF1 also targets various non-coding regions of the genome. Focusing primarily on mammals, this review aims at reporting the identity of the non-coding genomic sites directly bound by HSF1, and at describing the molecular function of the long non-coding RNAs (lncRNAs) produced in response to HSF1 binding. The described non-coding genomic targets of HSF1 are pericentric Satellite DNA repeats, (sub)telomeric DNA repeats, Short Interspersed Nuclear Element (SINE) repeats, transcriptionally active enhancers and the NEAT1 gene. This diverse set of non-coding genomic sites, which already appears to be an integral part of the cellular response to stress, may only represent the first of many. Thus, the study of the evolutionary conserved heat stress response has the potential to emerge as a powerful cellular context to study lncRNAs, produced from repeated or unique DNA regions, with a regulatory function that is often well-documented but a mode of action that remains largely unknown.
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Affiliation(s)
- Claire Vourc’h
- Université de Grenoble Alpes (UGA), 38700 La Tronche, France
- Correspondence: (C.V.); (A.V.)
| | - Solenne Dufour
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
| | - Kalina Timcheva
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
| | - Daphné Seigneurin-Berny
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
| | - André Verdel
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
- Correspondence: (C.V.); (A.V.)
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Lee KH, Kim DY, Kim W. Regulation of Gene Expression by Telomere Position Effect. Int J Mol Sci 2021; 22:ijms222312807. [PMID: 34884608 PMCID: PMC8657463 DOI: 10.3390/ijms222312807] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/23/2021] [Accepted: 11/24/2021] [Indexed: 11/16/2022] Open
Abstract
Many diseases that involve malignant tumors in the elderly affect the quality of human life; therefore, the relationship between aging and pathogenesis in geriatric diseases must be under-stood to develop appropriate treatments for these diseases. Recent reports have shown that epigenetic regulation caused by changes in the local chromatin structure plays an essential role in aging. This review provides an overview of the roles of telomere shortening on genomic structural changes during an age-dependent shift in gene expression. Telomere shortening is one of the most prominent events that is involved in cellular aging and it affects global gene expression through genome rearrangement. This review provides novel insights into the roles of telomere shortening in disease-affected cells during pathogenesis and suggests novel therapeutic approaches.
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Affiliation(s)
- Kyung-Ha Lee
- Division of Cosmetic Science and Technology, Daegu Haany University, Gyeongsan 38610, Korea;
| | - Do-Yeon Kim
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Korea
- Correspondence: (D.-Y.K.); (W.K.)
| | - Wanil Kim
- Department of Biochemistry, Department of Convergence Medical Science, Institute of Health Sciences, School of Medicine, Gyeongsang National University, Jinju 52727, Korea
- Correspondence: (D.-Y.K.); (W.K.)
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15
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Loss of telomere silencing is accompanied by dysfunction of Polo kinase and centrosomes during Drosophila oogenesis and early development. PLoS One 2021; 16:e0258156. [PMID: 34624021 PMCID: PMC8500440 DOI: 10.1371/journal.pone.0258156] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 09/18/2021] [Indexed: 12/03/2022] Open
Abstract
Telomeres are nucleoprotein complexes that protect the ends of eukaryotic linear chromosomes from degradation and fusions. Telomere dysfunction leads to cell growth arrest, oncogenesis, and premature aging. Telomeric RNAs have been found in all studied species; however, their functions and biogenesis are not clearly understood. We studied the mechanisms of development disorders observed upon overexpression of telomeric repeats in Drosophila. In somatic cells, overexpression of telomeric retrotransposon HeT-A is cytotoxic and leads to the accumulation of HeT-A Gag near centrosomes. We found that RNA and RNA-binding protein Gag encoded by the telomeric retrotransposon HeT-A interact with Polo and Cdk1 mitotic kinases, which are conserved regulators of centrosome biogenesis and cell cycle. The depletion of proteins Spindle E, Ccr4 or Ars2 resulting in HeT-A overexpression in the germline was accompanied by mislocalization of Polo as well as its abnormal stabilization during oogenesis and severe deregulation of centrosome biogenesis leading to maternal-effect embryonic lethality. These data suggest a mechanistic link between telomeric HeT-A ribonucleoproteins and cell cycle regulators that ensures the cell response to telomere dysfunction.
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16
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Remnant L, Kochanova NY, Reid C, Cisneros-Soberanis F, Earnshaw WC. The intrinsically disorderly story of Ki-67. Open Biol 2021; 11:210120. [PMID: 34375547 PMCID: PMC8354752 DOI: 10.1098/rsob.210120] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 07/13/2021] [Indexed: 01/14/2023] Open
Abstract
Ki-67 is one of the most famous marker proteins used by histologists to identify proliferating cells. Indeed, over 30 000 articles referring to Ki-67 are listed on PubMed. Here, we review some of the current literature regarding the protein. Despite its clinical importance, our knowledge of the molecular biology and biochemistry of Ki-67 is far from complete, and its exact molecular function(s) remain enigmatic. Furthermore, reports describing Ki-67 function are often contradictory, and it has only recently become clear that this proliferation marker is itself dispensable for cell proliferation. We discuss the unusual organization of the protein and its mRNA and how they relate to various models for its function. In particular, we focus on ways in which the intrinsically disordered structure of Ki-67 might aid in the assembly of the still-mysterious mitotic chromosome periphery compartment by controlling liquid-liquid phase separation of nucleolar proteins and RNAs.
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Affiliation(s)
- Lucy Remnant
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Natalia Y. Kochanova
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Caitlin Reid
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Fernanda Cisneros-Soberanis
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - William C. Earnshaw
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
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Wolffgramm J, Buchmuller B, Palei S, Muñoz‐López Á, Kanne J, Janning P, Schweiger MR, Summerer D. Light-Activation of DNA-Methyltransferases. Angew Chem Int Ed Engl 2021; 60:13507-13512. [PMID: 33826797 PMCID: PMC8251764 DOI: 10.1002/anie.202103945] [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: 03/19/2021] [Indexed: 12/27/2022]
Abstract
5-Methylcytosine (5mC), the central epigenetic mark of mammalian DNA, plays fundamental roles in chromatin regulation. 5mC is written onto genomes by DNA methyltransferases (DNMT), and perturbation of this process is an early event in carcinogenesis. However, studying 5mC functions is limited by the inability to control individual DNMTs with spatiotemporal resolution in vivo. We report light-control of DNMT catalysis by genetically encoding a photocaged cysteine as a catalytic residue. This enables translation of inactive DNMTs, their rapid activation by light-decaging, and subsequent monitoring of de novo DNA methylation. We provide insights into how cancer-related DNMT mutations alter de novo methylation in vivo, and demonstrate local and tuneable cytosine methylation by light-controlled DNMTs fused to a programmable transcription activator-like effector domain targeting pericentromeric satellite-3 DNA. We further study early events of transcriptome alterations upon DNMT-catalyzed cytosine methylation. Our study sets a basis to dissect the order and kinetics of diverse chromatin-associated events triggered by normal and aberrant DNA methylation.
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Affiliation(s)
- Jan Wolffgramm
- Faculty of Chemistry and Chemical BiologyTU Dortmund UniversityOtto-Hahn Str. 4a44227DortmundGermany
| | - Benjamin Buchmuller
- Faculty of Chemistry and Chemical BiologyTU Dortmund UniversityOtto-Hahn Str. 4a44227DortmundGermany
| | - Shubhendu Palei
- Faculty of Chemistry and Chemical BiologyTU Dortmund UniversityOtto-Hahn Str. 4a44227DortmundGermany
| | - Álvaro Muñoz‐López
- Faculty of Chemistry and Chemical BiologyTU Dortmund UniversityOtto-Hahn Str. 4a44227DortmundGermany
| | - Julian Kanne
- Department of Epigenetics and Tumor Biology, Medical FacultyUniversity of CologneKerpener Str. 6250937KölnGermany
| | - Petra Janning
- Max-Planck-Institute for Molecular PhysiologyOtto-Hahn-Str. 1144227DortmundGermany
| | - Michal R. Schweiger
- Department of Epigenetics and Tumor Biology, Medical FacultyUniversity of CologneKerpener Str. 6250937KölnGermany
| | - Daniel Summerer
- Faculty of Chemistry and Chemical BiologyTU Dortmund UniversityOtto-Hahn Str. 4a44227DortmundGermany
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18
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Wolffgramm J, Buchmuller B, Palei S, Muñoz‐López Á, Kanne J, Janning P, Schweiger MR, Summerer D. Light‐Activation of DNA‐Methyltransferases. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jan Wolffgramm
- Faculty of Chemistry and Chemical Biology TU Dortmund University Otto-Hahn Str. 4a 44227 Dortmund Germany
| | - Benjamin Buchmuller
- Faculty of Chemistry and Chemical Biology TU Dortmund University Otto-Hahn Str. 4a 44227 Dortmund Germany
| | - Shubhendu Palei
- Faculty of Chemistry and Chemical Biology TU Dortmund University Otto-Hahn Str. 4a 44227 Dortmund Germany
| | - Álvaro Muñoz‐López
- Faculty of Chemistry and Chemical Biology TU Dortmund University Otto-Hahn Str. 4a 44227 Dortmund Germany
| | - Julian Kanne
- Department of Epigenetics and Tumor Biology, Medical Faculty University of Cologne Kerpener Str. 62 50937 Köln Germany
| | - Petra Janning
- Max-Planck-Institute for Molecular Physiology Otto-Hahn-Str. 11 44227 Dortmund Germany
| | - Michal R. Schweiger
- Department of Epigenetics and Tumor Biology, Medical Faculty University of Cologne Kerpener Str. 62 50937 Köln Germany
| | - Daniel Summerer
- Faculty of Chemistry and Chemical Biology TU Dortmund University Otto-Hahn Str. 4a 44227 Dortmund Germany
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Legoff L, D'Cruz SC, Bouchekhchoukha K, Monfort C, Jaulin C, Multigner L, Smagulova F. In utero exposure to chlordecone affects histone modifications and activates LINE-1 in cord blood. Life Sci Alliance 2021; 4:4/6/e202000944. [PMID: 33837044 PMCID: PMC8091598 DOI: 10.26508/lsa.202000944] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 03/26/2021] [Accepted: 03/29/2021] [Indexed: 01/06/2023] Open
Abstract
In utero exposure to chlordecone affects chromatin and leads to activation of retroelements. This study shows the changes induced by chlordecone in human umbilical cord blood and blood-derived cell line. Environmental factors can induce detrimental consequences into adulthood life. In this study, we examined the epigenetic effects induced by in utero chlordecone (CD) exposure on human male cord blood as well as in blood-derived Ke-37 cell line. Genome-wide analysis of histone H3K4me3 distribution revealed that genes related to chromosome segregation, chromatin organization, and cell cycle have altered occupancy in their promoters. The affected regions were enriched in ESR1, SP family, and IKZF1 binding motifs. We also observed a global reduction in H3K9me3, markedly in repeated sequences of the genome. Decrease in H3K9me3 after CD exposure correlates with decreased methylation in LINE-1 promoters and telomere length extension. These observations on human cord blood were assessed in the Ke-37 human cell line. H3K4me3 and the expression of genes related to immune response, DNA repair, and chromatin organization, which were affected in human cord blood were also altered in CD-exposed Ke-37 cells. Our data suggest that developmental exposure to CD leads to profound changes in histone modification patterns and affects the processes controlled by them in human cord blood.
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Affiliation(s)
- Louis Legoff
- University of Rennes, EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail (Irset)-UMR_S 1085, Rennes, France
| | - Shereen Cynthia D'Cruz
- University of Rennes, EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail (Irset)-UMR_S 1085, Rennes, France
| | - Katia Bouchekhchoukha
- University of Rennes, EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail (Irset)-UMR_S 1085, Rennes, France
| | - Christine Monfort
- University of Rennes, EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail (Irset)-UMR_S 1085, Rennes, France
| | - Christian Jaulin
- Institut de Génétique et Développement de Rennes, Epigenetics and Cancer Group, UMR 6290 CNRS, Université Rennes 1, Rennes Cedex, France
| | - Luc Multigner
- University of Rennes, EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail (Irset)-UMR_S 1085, Rennes, France
| | - Fatima Smagulova
- University of Rennes, EHESP, Inserm, Institut de Recherche en Santé, Environnement et Travail (Irset)-UMR_S 1085, Rennes, France
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20
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Emerging roles of centromeric RNAs in centromere formation and function. Genes Genomics 2021; 43:217-226. [PMID: 33523401 DOI: 10.1007/s13258-021-01041-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 01/04/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND Centromeres are specialized chromosomal domains involved in kinetochore formation and faithful chromosome segregation. Despite a high level of functional conservation, centromeres are not identified by DNA sequences, but by epigenetic means. Universally, centromeres are typically formed on highly repetitive DNA, which were previously considered to be silent. However, recent studies have shown that transcription occurs in this region, known as centromeric-derived RNAs (cenRNAs). CenRNAs that contribute to fundamental aspects of centromere function have been recently investigated in detail. However, the distribution, behavior and contributions of centromeric transcripts are still poorly understood. OBJECTIVE The aim of this article is to provide an overview of the roles of cenRNAs in centromere formation and function. METHODS We describe the structure and DNA sequence of centromere from yeast to human. In addition, we briefly introduce the roles of cenRNAs in centromere formation and function, kinetochore structure, accurate chromosome segregation, and pericentromeric heterochromatin assembly. Centromeric circular RNAs (circRNAs) and R-loops are rising stars in centromere function. CircRNAs have been successfully identified in various species with the assistance of high-throughput sequencing and novel computational approaches for non-polyadenylated RNA transcripts. Centromeric R-loops can be identified by the single-strand DNA ligation-based library preparation technique. But the molecular features and function of these centromeric R-loops and circRNAs are still being investigated. CONCLUSION In this review, we summarize recent findings on the epigenetic regulation of cenRNAs across species, which would provide useful information about cenRNAs and interesting hints for further studies.
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21
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Sun C, Li J, Dong J, Niu Y, Hu J, Lian J, Li W, Li J, Tian Y, Shi Q, Ye X. Chromosome-level genome assembly for the largemouth bass Micropterus salmoides provides insights into adaptation to fresh and brackish water. Mol Ecol Resour 2020; 21:301-315. [PMID: 32985096 DOI: 10.1111/1755-0998.13256] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 08/19/2020] [Accepted: 08/24/2020] [Indexed: 12/16/2022]
Abstract
Largemouth bass (LMB; Micropterus salmoides) has been an economically important fish in North America, Europe, and China. This study obtained a chromosome-level genome assembly of LMB using PacBio and Hi-C sequencing. The final assembled genome is 964 Mb, with contig N50 and scaffold N50 values of 1.23 Mb and 36.48 Mb, respectively. Combining with RNA sequencing data, we annotated a total of 23,701 genes. Chromosomal assembly and syntenic analysis proved that, unlike most Perciformes with the popular haploid chromosome number of 24, LMB has only 23 chromosomes (Chr), among which the Chr1 seems to be resulted from a chromosomal fusion event. LMB is phylogenetically closely related to European seabass and spotted seabass, diverging 64.1 million years ago (mya) from the two seabass species. Eight gene families comprising 294 genes associated with ionic regulation were identified through positive selection, transcriptome and genome comparisons. These genes involved in iron facilitated diffusion (such as claudin, aquaporins, sodium channel protein and so on) and others related to ion active transport (such as sodium/potassium-transporting ATPase and sodium/calcium exchanger). The claudin gene family, which is critical for regulating cell tight junctions and osmotic homeostasis, showed a significant expansion in LMB with 27 family members and 68 copies for salinity adaptation. In summary, we reported the first high-quality LMB genome, and provided insights into the molecular mechanisms of LMB adaptation to fresh and brackish water. The chromosome-level LMB genome will also be a valuable genomic resource for in-depth biological and evolutionary studies, germplasm conservation and genetic breeding of LMB.
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Affiliation(s)
- Chengfei Sun
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Jia Li
- Shenzhen Key Laboratory of Marine Genomics, Guangdong Provincial Key Laboratory of Molecular Breeding in Marine Economic Animals, BGI Academy of Marine Sciences, BGI Marine, BGI, Shenzhen, China
| | - Junjian Dong
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | | | - Jie Hu
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | | | - Wuhui Li
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Jiang Li
- Biozeron Shenzhen Inc., Shenzhen, China
| | - Yuanyuan Tian
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Qiong Shi
- Shenzhen Key Laboratory of Marine Genomics, Guangdong Provincial Key Laboratory of Molecular Breeding in Marine Economic Animals, BGI Academy of Marine Sciences, BGI Marine, BGI, Shenzhen, China
| | - Xing Ye
- Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation, Ministry of Agriculture and Rural Affairs, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
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Impact of Ovarian Aging in Reproduction: From Telomeres and Mice Models to Ovarian Rejuvenation. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2020; 93:561-569. [PMID: 33005120 PMCID: PMC7513441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The trend in our society to delay procreation increases the difficulty to conceive spontaneously. Thus, there is a growing need to use assisted reproduction technologies (ART) to form a family. With advanced maternal age, ovaries not only produce a lower number of oocytes after ovarian stimulation but also a lower quality-mainly aneuploidies-requiring further complex analysis to avoid complications during implantation and pregnancy. Although there are different options to have a child at advanced maternal age (like donor eggs), this is not the preferred choice for most patients. Unless women had cryopreserved their eggs at a younger age, reproductive medicine should try to optimize their opportunities to become pregnant with their own oocytes, when chances of success are reasonable. Aging has many causes, but telomere attrition is ultimately one of the main pathways involved in this process. Several reports link telomere biology and reproduction, but the molecular reasons for the rapid loss of ovarian function at middle age are still elusive. This review will focus on the knowledge acquired during the last years about ovarian aging and disease, both in mouse models of reproductive senescence and in humans with ovarian failure, and the implication of telomeres in this process. In addition, the review will discuss recent results on ovarian rejuvenation, achieved with stem cell therapies that are currently under study, or ovarian reactivation by tissue fragmentation and the attempts to generate oocytes in vitro.
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Telomere instability initiates and then boosts carcinogenesis by the butterfly effect. Curr Opin Genet Dev 2020; 60:92-98. [PMID: 32199233 DOI: 10.1016/j.gde.2020.01.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/22/2020] [Accepted: 01/28/2020] [Indexed: 12/20/2022]
Abstract
Telomeres are composed of DNA repeat sequences at the ends of chromosomes that recruit a multitude of proteins to form a complex loop structure at each extremity. The integrity of this structure is critical and correct conformation of the loop is essential for the protection of chromosome ends from DDR signaling. The properties of telomere composition and synthesis result in telomere shortening at each cell division, programming cellular lifespan by driving aged cells towards death. Indeed, many external factors, such as cellular stress, trigger cell-cycle dysfunction and, in some cases, enable the survival of cells with dysfunctionally short telomeres. Destabilized loops at chromosome ends can then lead to dramatic consequences, via a butterfly effect such as multiple chromosomal fusions and rearrangements causing large chromosomal deletions, XXL-LOH (loss of heterozygoty due to very large chromosome deletions, up to whole chromosome arm), the expression of recessive mutations, and potential cell transformation.
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Feng JX, Riddle NC. Epigenetics and genome stability. Mamm Genome 2020; 31:181-195. [PMID: 32296924 DOI: 10.1007/s00335-020-09836-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 04/07/2020] [Indexed: 12/19/2022]
Abstract
Maintaining genome stability is essential to an organism's health and survival. Breakdown of the mechanisms protecting the genome and the resulting genome instability are an important aspect of the aging process and have been linked to diseases such as cancer. Thus, a large network of interconnected pathways is responsible for ensuring genome integrity in the face of the continuous challenges that induce DNA damage. While these pathways are diverse, epigenetic mechanisms play a central role in many of them. DNA modifications, histone variants and modifications, chromatin structure, and non-coding RNAs all carry out a variety of functions to ensure that genome stability is maintained. Epigenetic mechanisms ensure the functions of centromeres and telomeres that are essential for genome stability. Epigenetic mechanisms also protect the genome from the invasion by transposable elements and contribute to various DNA repair pathways. In this review, we highlight the integral role of epigenetic mechanisms in the maintenance of genome stability and draw attention to issues in need of further study.
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Affiliation(s)
- Justina X Feng
- Department of Biology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nicole C Riddle
- Department of Biology, The University of Alabama at Birmingham, Birmingham, AL, USA.
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Srinivas N, Rachakonda S, Kumar R. Telomeres and Telomere Length: A General Overview. Cancers (Basel) 2020; 12:E558. [PMID: 32121056 PMCID: PMC7139734 DOI: 10.3390/cancers12030558] [Citation(s) in RCA: 138] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/24/2020] [Accepted: 02/26/2020] [Indexed: 02/06/2023] Open
Abstract
Telomeres are highly conserved tandem nucleotide repeats that include proximal double-stranded and distal single-stranded regions that in complex with shelterin proteins afford protection at chromosomal ends to maintain genomic integrity. Due to the inherent limitations of DNA replication and telomerase suppression in most somatic cells, telomeres undergo age-dependent incremental attrition. Short or dysfunctional telomeres are recognized as DNA double-stranded breaks, triggering cells to undergo replicative senescence. Telomere shortening, therefore, acts as a counting mechanism that drives replicative senescence by limiting the mitotic potential of cells. Telomere length, a complex hereditary trait, is associated with aging and age-related diseases. Epidemiological data, in general, support an association with varying magnitudes between constitutive telomere length and several disorders, including cancers. Telomere attrition is also influenced by oxidative damage and replicative stress caused by genetic, epigenetic, and environmental factors. Several single nucleotide polymorphisms at different loci, identified through genome-wide association studies, influence inter-individual variation in telomere length. In addition to genetic factors, environmental factors also influence telomere length during growth and development. Telomeres hold potential as biomarkers that reflect the genetic predisposition together with the impact of environmental conditions and as targets for anti-cancer therapies.
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Affiliation(s)
| | | | - Rajiv Kumar
- Division of Functional Genome Analysis, German Cancer Research Center, Im Neunheimer Feld 580, 69120 Heidelberg, Germany; (N.S.); (S.R.)
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26
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Bhattacharjee P, Das A, Giri AK, Bhattacharjee P. Epigenetic regulations in alternative telomere lengthening: Understanding the mechanistic insight in arsenic-induced skin cancer patients. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 704:135388. [PMID: 31837846 DOI: 10.1016/j.scitotenv.2019.135388] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 11/01/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
Telomere integrity is considered to be one of the primary mechanisms during malignant transformation. Arsenic, a group 1 carcinogenic metalloid, has been reported to cause telomere lengthening in a telomerase-independent manner. Recent studies suggest a significant role for epigenetic modifications in regulating telomeric length and integrity. Here, we have explored the role of epigenetic deregulation in alternative lengthening of telomeres (ALT) in arsenic-exposed skin cancer tissues and corresponding non-tumor tissues. The relative telomere length (RTL) was analyzed by qRT-PCR using 2-ΔΔCt method. The subtelomeric methylation pattern of the four chromosomes (7q, 18p, 21q and XpYp) were analysed by Methylation Specific PCR (MSP) in 40 pairs of arsenic exposed skin cancer tissues and its corresponding control. The role of constitutive heterochromatin histone marks in the regulation of telomere length (TL) was analyzed by targeted ELISA. A 2-fold increase of relative telomere length in 85% of the arsenic-induced skin cancer tissues was observed. Among the four chromosomes, subtelomere of XpYp was found to be hypermethylated (p < 0.001) whereas 18p was hypomethylated (p < 0.01). Additionally, the level of H4K20me3, a heterochromatic mark was found to be significantly down-regulated (p < 0.0003), and inversely correlated with telomere length indicating loss of heterochromatinization of telomeric DNA. These observations highlight the novel role of epigenetic regulation in the maintenance of constitutive heterochromatin structure at telomere. Alteration in subtelomeric DNA methylation patterns and depletion of H4K20me3 might lead to loss of heterochromatinization resulting in arsenic-induced telomeric elongation. We provide novel data indicating possible alternative determinants of telomere elongation through epigenetic modifications during arsenic-induced skin carcinogenesis which could be used as early 'epimarkers' in the near future. The findings provide new insights about the mechanism of arsenic-induced carcinogenesis.
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Affiliation(s)
- Pritha Bhattacharjee
- Department of Zoology, University of Calcutta, Kolkata 700019, India; Department of Environmental Science, University of Calcutta, Kolkata 700019, India
| | - Ankita Das
- Department of Environmental Science, University of Calcutta, Kolkata 700019, India
| | - Ashok K Giri
- Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Pritha Bhattacharjee
- Department of Environmental Science, University of Calcutta, Kolkata 700019, India.
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Kwapisz M, Morillon A. Subtelomeric Transcription and its Regulation. J Mol Biol 2020; 432:4199-4219. [PMID: 32035903 PMCID: PMC7374410 DOI: 10.1016/j.jmb.2020.01.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 01/14/2020] [Accepted: 01/14/2020] [Indexed: 12/13/2022]
Abstract
The subtelomeres, highly heterogeneous repeated sequences neighboring telomeres, are transcribed into coding and noncoding RNAs in a variety of organisms. Telomereproximal subtelomeric regions produce non-coding transcripts i.e., ARRET, αARRET, subTERRA, and TERRA, which function in telomere maintenance. The role and molecular mechanisms of the majority of subtelomeric transcripts remain unknown. This review depicts the current knowledge and puts into perspective the results obtained in different models from yeasts to humans.
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Affiliation(s)
- Marta Kwapisz
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, France
| | - Antonin Morillon
- ncRNA, Epigenetic and Genome Fluidity, CNRS UMR 3244, Sorbonne Université, PSL University, Institut Curie, Centre de Recherche, 26 rue d'Ulm, 75248, Paris, France.
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28
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Aschacher T, Wolf B, Aschacher O, Enzmann F, Laszlo V, Messner B, Türkcan A, Weis S, Spiegl-Kreinecker S, Holzmann K, Laufer G, Ehrlich M, Bergmann M. Long interspersed element-1 ribonucleoprotein particles protect telomeric ends in alternative lengthening of telomeres dependent cells. Neoplasia 2019; 22:61-75. [PMID: 31846834 PMCID: PMC6920197 DOI: 10.1016/j.neo.2019.11.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 11/13/2019] [Accepted: 11/14/2019] [Indexed: 12/21/2022] Open
Abstract
Malignant cells ensure telomere maintenance by the alternative lengthening of telomeres (ALT) in the absence of telomerase activity (TA). The retrotransposons "long interspersed nuclear element-1" (LINE-1, L1) are expressed in malignant cells and are primarily known to contribute to complex karyotypes. Here we demonstrate that LINE-1 ribonucleoprotein particles (L1-RNPs) expression is significantly higher in ALT+- versus in TA+-human glioma. Analyzing a role of L1-RNP in ALT, we show that L1-RNPs bind to telomeric repeat containing RNA (TERRA), which is critical for telomere stabilization and which is overexpressed in ALT+ cells. In turn, L1-RNP knockdown (KD) abrogated the nuclear retention of TERRA, resulted in increased telomeric DNA damage, decreased cell growth and reduced expression of ALT characteristics such as c-circles and PML-bodies. L1-RNP KD also decreased the expression of Shelterin- and the ALT-regulating protein Topoisomerase IIIα (TopoIIIα) indicating a more general role of L1-RNPs in supporting telomeric integrity in ALT. Our findings suggest an impact of L1-RNP on telomere stability in ALT+ dependent tumor cells. As L1-RNPs are rarely expressed in normal adult human tissue those elements might serve as a novel target for tumor ablative therapy.
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Affiliation(s)
- Thomas Aschacher
- Cardiac Surgery Research Laboratory, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Brigitte Wolf
- Surgical Research Laboratories, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Olivia Aschacher
- Department of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Florian Enzmann
- Department of Vascular and Endovascular Surgery, Paracelsus Medical University Salzburg, Muellner Hauptstraße 48, 5020 Salzburg, Austria
| | - Viktoria Laszlo
- Surgical Research Laboratories, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Barbara Messner
- Cardiac Surgery Research Laboratory, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Adrian Türkcan
- Surgical Research Laboratories, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Serge Weis
- Division of Neuropathology, Neuromed Campus, Kepler University Hospital, 4020 Linz, Austria
| | - Sabine Spiegl-Kreinecker
- University Clinic for Neurosurgery, Neuromed Campus, Kepler University Hospital, Johannes Kepler University, Linz, Austria
| | - Klaus Holzmann
- Department of Cancer Research, Borschkegasse 8a, 1090 Vienna, Austria; Comprehensive Cancer Centre, Medical University of Vienna, Austria
| | - Günther Laufer
- Cardiac Surgery Research Laboratory, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Marek Ehrlich
- Cardiac Surgery Research Laboratory, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria
| | - Michael Bergmann
- Surgical Research Laboratories, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, 1090 Vienna, Austria; Comprehensive Cancer Centre, Medical University of Vienna, Austria.
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29
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Park J, Zhu Q, Mirek E, Na L, Raduwan H, Anthony TG, Belden WJ. BMAL1 associates with chromosome ends to control rhythms in TERRA and telomeric heterochromatin. PLoS One 2019; 14:e0223803. [PMID: 31634367 PMCID: PMC6802832 DOI: 10.1371/journal.pone.0223803] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 09/27/2019] [Indexed: 01/12/2023] Open
Abstract
The circadian clock and aging are intertwined. Disruption to the normal diurnal rhythm accelerates aging and corresponds with telomere shortening. Telomere attrition also correlates with increase cellular senescence and incidence of chronic disease. In this report, we examined diurnal association of White Collar 2 (WC-2) in Neurospora and BMAL1 in zebrafish and mice and found that these circadian transcription factors associate with telomere DNA in a rhythmic fashion. We also identified a circadian rhythm in Telomeric Repeat-containing RNA (TERRA), a lncRNA transcribed from the telomere. The diurnal rhythm in TERRA was lost in the liver of Bmal1-/- mice indicating it is a circadian regulated transcript. There was also a BMAL1-dependent rhythm in H3K9me3 at the telomere in zebrafish brain and mouse liver, and this rhythm was lost with increasing age. Taken together, these results provide evidence that BMAL1 plays a direct role in telomere homeostasis by regulating rhythms in TERRA and heterochromatin. Loss of these rhythms may contribute to telomere erosion during aging.
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Affiliation(s)
- Jinhee Park
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States of America
| | - Qiaoqiao Zhu
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States of America
| | - Emily Mirek
- Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States of America
| | - Li Na
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States of America
| | - Hamidah Raduwan
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States of America
| | - Tracy G. Anthony
- Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States of America
| | - William J. Belden
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States of America
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30
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Xu J, Tsai CW, Chang WS, Han Y, Bau DT, Pettaway CA, Gu J. Methylation of global DNA repeat LINE-1 and subtelomeric DNA repeats D4Z4 in leukocytes is associated with biochemical recurrence in African American prostate cancer patients. Carcinogenesis 2019; 40:1055-1060. [PMID: 30874286 DOI: 10.1093/carcin/bgz061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 03/06/2019] [Accepted: 03/12/2019] [Indexed: 11/13/2022] Open
Abstract
Global DNA methylation may play important roles in cancer etiology and prognosis. The goal of this study is to investigate whether the methylation of long interspersed nucleotide elements (LINE-1) and subtelomeric DNA repeats D4Z4 in leukocyte DNA is associated with aggressive prostate cancer (PCa) in African Americans. We measured DNA methylation levels of LINE-1 and D4Z4 in 306 African American (AA) PCa patients using pyrosequencing and compared their methylation levels among clinical variables. We further applied multivariate Cox proportional hazards model and Kaplan-Meier survival function and log-rank tests to assess the association between DNA methylation and biochemical recurrence (BCR). Overall, there was no significant difference of the methylation levels of LINE-1 and D4Z4 among patients with different clinical and epidemiological characteristics. However, the methylation of LINE-1 and D4Z4 was associated with BCR. Patients with lower LINE-1 methylation and higher D4Z4 methylation exhibited markedly increased risks of BCR with adjusted hazard ratios of 3.34 (95% confidence interval, 1.32-8.45) and 4.12 (95% confidence interval, 1.32-12.86), respectively, and significantly shorter BCR-free survival times. Our results suggest that lower global DNA methylation and higher subtelomeric region methylation may predict worse prognosis in localized AA PCa patients.
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Affiliation(s)
- Junfeng Xu
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Chia-Wen Tsai
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
| | - Wen-Shin Chang
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
| | - Yuyan Han
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Da-Tian Bau
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
| | - Curtis A Pettaway
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jian Gu
- Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Pompili L, Maresca C, Dello Stritto A, Biroccio A, Salvati E. BRCA2 Deletion Induces Alternative Lengthening of Telomeres in Telomerase Positive Colon Cancer Cells. Genes (Basel) 2019; 10:genes10090697. [PMID: 31510074 PMCID: PMC6771010 DOI: 10.3390/genes10090697] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/16/2019] [Accepted: 09/03/2019] [Indexed: 11/25/2022] Open
Abstract
BRCA1/2 are tumor suppressor genes controlling genomic stability also at telomeric and subtelomeric loci. Their mutation confers a predisposition to different human cancers but also sensitivity to antitumor drugs including poly(ADP-ribose) polymerase (PARP) inhibitors and G-quadruplex stabilizers. Here we demonstrate that BRCA2 deletion triggers TERRA hyperexpression and alternative lengthening mechanisms (ALT) in colon cancer cells in presence of telomerase activity. This finding opens the question if cancer patients bearing BRCA2 germline or sporadic mutation are suitable for anti-telomerase therapies, or how ALT activation could influence the short or long-term response to anti-PARP inhibitors or anti-G-quadruplex therapies.
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Affiliation(s)
- Luca Pompili
- Oncogenomic and Epigenetic Unit, IRCSS Regina Elena National Cancer Institute, Via Elio Chianesi, 53-00144 Rome, Italy.
| | - Carmen Maresca
- Oncogenomic and Epigenetic Unit, IRCSS Regina Elena National Cancer Institute, Via Elio Chianesi, 53-00144 Rome, Italy.
| | - Angela Dello Stritto
- Biology and Biotechnology Department "Charles Darwin", Sapienza University of Rome, Piazzale Aldo Moro, 5-00185 Rome, Italy.
| | - Annamaria Biroccio
- Oncogenomic and Epigenetic Unit, IRCSS Regina Elena National Cancer Institute, Via Elio Chianesi, 53-00144 Rome, Italy.
| | - Erica Salvati
- Oncogenomic and Epigenetic Unit, IRCSS Regina Elena National Cancer Institute, Via Elio Chianesi, 53-00144 Rome, Italy.
- Institute of Molecular Biology and Pathology, CNR, Via degli Apuli, 4-00185 Rome, Italy.
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32
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Yandım C, Karakülah G. Dysregulated expression of repetitive DNA in ER+/HER2- breast cancer. Cancer Genet 2019; 239:36-45. [PMID: 31536958 DOI: 10.1016/j.cancergen.2019.09.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 07/03/2019] [Accepted: 09/05/2019] [Indexed: 12/12/2022]
Abstract
Limited studies on breast cancer indicated pathogenic changes in the expressions of some repeat elements. A global analysis was much needed within this context to distinguish the most significant repeats from more than a thousand repeat motifs. Utilising a previously presented RNA-seq dataset, we studied expression changes of all repeats in ER+/HER2- human breast tumour samples obtained from 22 patients in comparison to matched normal tissues. Fifty six (56) repeat subtypes including satellites and transposons were found to be differentially expressed and most of them were novel for breast cancer. HERVKC4-int and HERV1_LTRc, whose expressions correlated well with that of the estrogen receptor gene ESR1, were upregulated at the highest level. REP522 and D20S16 satellites were also significantly upregulated along with insignificant increases in the expressions of other satellites including HSATI and BSR/beta. Interestingly, expressions of REP522 and D20S16 correlated with many key breast cancer pathway (e.g. BRCA1, BRCA2, AKT1, MTOR, KRAS) and survival genes; possibly highlighting their importance in the carcinogenesis of breast. Additional differentially expressed elements such as L1P and various MER transposons also exhibited a similar pattern. Finally, our repeat enrichment analysis on the promoters of differentially expressed genes revealed further links between additional repeats and nearby genes.
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Affiliation(s)
- Cihangir Yandım
- İzmir University of Economics, Faculty of Engineering, Department of Genetics and Bioengineering, 35330, Balçova, İzmir, Turkey; İzmir Biomedicine and Genome Center (IBG), Dokuz Eylül University Health Campus, 35340, İnciraltı, İzmir, Turkey
| | - Gökhan Karakülah
- İzmir Biomedicine and Genome Center (IBG), Dokuz Eylül University Health Campus, 35340, İnciraltı, İzmir, Turkey; İzmir International Biomedicine and Genome Institute (iBG-İzmir), Dokuz Eylül University, 35340, İnciraltı, İzmir, Turkey.
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33
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Mazzolini R, Gonzàlez N, Garcia-Garijo A, Millanes-Romero A, Peiró S, Smith S, García de Herreros A, Canudas S. Snail1 transcription factor controls telomere transcription and integrity. Nucleic Acids Res 2019; 46:146-158. [PMID: 29059385 PMCID: PMC5758914 DOI: 10.1093/nar/gkx958] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 10/16/2017] [Indexed: 02/06/2023] Open
Abstract
Besides controlling epithelial-to-mesenchymal transition (EMT) and cell invasion, the Snail1 transcriptional factor also provides cells with cancer stem cell features. Since telomere maintenance is essential for stemness, we have examined the control of telomere integrity by Snail1. Fluorescence in situ hybridization (FISH) analysis indicates that Snail1-depleted mouse mesenchymal stem cells (MSC) have both a dramatic increase of telomere alterations and shorter telomeres. Remarkably, Snail1-deficient MSC present higher levels of both telomerase activity and the long non-coding RNA called telomeric repeat-containing RNA (TERRA), an RNA that controls telomere integrity. Accordingly, Snail1 expression downregulates expression of the telomerase gene (TERT) as well as of TERRA 2q, 11q and 18q. TERRA and TERT are transiently downregulated during TGFβ-induced EMT in NMuMG cells, correlating with Snail1 expression. Global transcriptome analysis indicates that ectopic expression of TERRA affects the transcription of some genes induced during EMT, such as fibronectin, whereas that of TERT does not modify those genes. We propose that Snail1 repression of TERRA is required not only for telomere maintenance but also for the expression of a subset of mesenchymal genes.
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Affiliation(s)
- Rocco Mazzolini
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Núria Gonzàlez
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Andrea Garcia-Garijo
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Alba Millanes-Romero
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Sandra Peiró
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain
| | - Susan Smith
- Kimmel Center for Biology and Medicine at the Skirball Institute, Department of Pathology, New York University School of Medicine, New York University, USA
| | - Antonio García de Herreros
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain.,Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Sílvia Canudas
- Programa de Recerca en Càncer, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Barcelona, Spain.,Unitat de Nutrició Humana, Facultat de Medicina i Ciències de la Salut, Institut d'Investigació Sanitaria Pere Virgili (IISPV), Reus, Spain.,CIBER Fisiología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
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34
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Role of arsenic, lead and cadmium on telomere length and the risk of carcinogenesis: a mechanistic insight. THE NUCLEUS 2019. [DOI: 10.1007/s13237-019-00280-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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35
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Brunner E, Yagi R, Debrunner M, Beck-Schneider D, Burger A, Escher E, Mosimann C, Hausmann G, Basler K. CRISPR-induced double-strand breaks trigger recombination between homologous chromosome arms. Life Sci Alliance 2019; 2:e201800267. [PMID: 31196871 PMCID: PMC6587125 DOI: 10.26508/lsa.201800267] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 05/29/2019] [Accepted: 05/29/2019] [Indexed: 12/27/2022] Open
Abstract
CRISPR-Cas9-based genome editing has transformed the life sciences, enabling virtually unlimited genetic manipulation of genomes: The RNA-guided Cas9 endonuclease cuts DNA at a specific target sequence and the resulting double-strand breaks are mended by one of the intrinsic cellular repair pathways. Imprecise double-strand repair will introduce random mutations such as indels or point mutations, whereas precise editing will restore or specifically edit the locus as mandated by an endogenous or exogenously provided template. Recent studies indicate that CRISPR-induced DNA cuts may also result in the exchange of genetic information between homologous chromosome arms. However, conclusive data of such recombination events in higher eukaryotes are lacking. Here, we show that in Drosophila, the detected Cas9-mediated editing events frequently resulted in germline-transmitted exchange of chromosome arms-often without indels. These findings demonstrate the feasibility of using the system for generating recombinants and also highlight an unforeseen risk of using CRISPR-Cas9 for therapeutic intervention.
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Affiliation(s)
- Erich Brunner
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Ryohei Yagi
- Institute of Molecular Systems Biology, Eidgenössische Technische Hochschule Zurich, Zurich, Switzerland
| | - Marc Debrunner
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | | | - Alexa Burger
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Eliane Escher
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Christian Mosimann
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - George Hausmann
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Konrad Basler
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
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36
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Kordyukova MY, Kalmykova AI. Nature and Functions of Telomeric Transcripts. BIOCHEMISTRY (MOSCOW) 2019; 84:137-146. [DOI: 10.1134/s0006297919020044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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37
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Liang X, Hou X, Li J, Han Y, Zhang Y, Feng N, Du J, Zhang W, Zheng D, Fang S. High-resolution DNA methylome reveals that demethylation enhances adaptability to continuous cropping comprehensive stress in soybean. BMC PLANT BIOLOGY 2019; 19:79. [PMID: 30777019 PMCID: PMC6380062 DOI: 10.1186/s12870-019-1670-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 02/01/2019] [Indexed: 05/10/2023]
Abstract
BACKGROUND Continuous cropping stress involves such factors as biological barriers, allelopathic autotoxicity, deterioration of soil physicochemical properties, and soil fertility imbalance and is regarded as a kind of comprehensive stress limiting soybean yield and quality. Genomic DNA methylation is an important regulatory mechanism for plants to resist various environmental stresses. Therefore, it is especially worthwhile to reveal genomic methylation characteristics under stress and clarify the relationship between DNA methylation status and continuous cropping stress adaptability in soybean. RESULTS We generated a genome-wide map of cytosine methylation induced by this kind of comprehensive stress in a tolerant soybean variety (Kang Xian 2, KX2) and a sensitive variety (He Feng, HF55) using whole-genome bisulfite sequencing (WGBS) technology. The expression of DNA demethylase genes was detected using real-time quantitative PCR (qRT-PCR). The functions of differentially methylated genes (DMGs) involved in stress response in biochemical metabolism and genetic information transmission were further assessed based on Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The results showed that genomic DNA demethylation was closely related to continuous cropping comprehensive stress adaptability in soybean, which was further verified by the increasing expression of DNA demethylases ROS1 and DML. The demethylation of mCpG and mCpHpG (mCpApG preferred) contexts was more critical, which mainly occurred in gene-regulatory regions at the whole-chromosome scale. Moreover, this kind of stress adaptability may be related to various stress responders generated through strengthened glucose catabolism and amino acid and fatty acid anabolism, as well as fidelity transmission of genetic information. CONCLUSIONS Genomic DNA demethylation was closely associated with continuous cropping comprehensive stress adaptability, highlighting the promising potential of screening continuous cropping-tolerant cultivars by DNA methylation index and further exploring the application of DNA demethylases in soybean breeding.
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Affiliation(s)
- Xilong Liang
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Xue Hou
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Jianying Li
- Daqing Branch of Heilongjiang Academy of Agriculture Science, Daqing, 163316 China
| | - Yiqiang Han
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Yuxian Zhang
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Naijie Feng
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Jidao Du
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Wenhui Zhang
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Dianfeng Zheng
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
| | - Shumei Fang
- Heilongjiang Bayi Agricultural University, Daqing, 163319 China
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38
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Sousa‐Franco A, Rebelo K, da Rocha ST, Bernardes de Jesus B. LncRNAs regulating stemness in aging. Aging Cell 2019; 18:e12870. [PMID: 30456884 PMCID: PMC6351848 DOI: 10.1111/acel.12870] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 09/18/2018] [Accepted: 09/28/2018] [Indexed: 12/21/2022] Open
Abstract
One of the most outstanding observations from next-generation sequencing approaches was that only 1.5% of our genes code for proteins. The biggest part is transcribed but give rise to different families of RNAs without coding potential. The functional relevance of these abundant transcripts remains far from elucidated. Among them are the long non-coding RNAs (lncRNAs), a relatively large and heterogeneous group of RNAs shown to be highly tissue-specific, indicating a prominent role in processes controlling cellular identity. In particular, lncRNAs have been linked to both stemness properties and detrimental pathways regulating the aging process, being novel players in the intricate network guiding tissue homeostasis. Here, we summarize the up-to-date information on the role of lncRNAs that affect stemness and hence impact upon aging, highlighting the likelihood that lncRNAs may represent an unexploited reservoir of potential therapeutic targets for reprogramming applications and aging-related diseases.
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Affiliation(s)
- António Sousa‐Franco
- Instituto de Medicina MolecularFaculdade de Medicina da Universidade de LisboaLisboaPortugal
| | - Kenny Rebelo
- Instituto de Medicina MolecularFaculdade de Medicina da Universidade de LisboaLisboaPortugal
| | - Simão Teixeira da Rocha
- Instituto de Medicina MolecularFaculdade de Medicina da Universidade de LisboaLisboaPortugal
| | - Bruno Bernardes de Jesus
- Instituto de Medicina MolecularFaculdade de Medicina da Universidade de LisboaLisboaPortugal
- Department of Medical Sciences and Institute of Biomedicine—iBiMEDUniversity of AveiroAveiroPortugal
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Harrington L, Pucci F. In medio stat virtus: unanticipated consequences of telomere dysequilibrium. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2016.0444. [PMID: 29335368 PMCID: PMC5784064 DOI: 10.1098/rstb.2016.0444] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2017] [Indexed: 12/13/2022] Open
Abstract
The integrity of chromosome ends, or telomeres, depends on myriad processes that must balance the need to compact and protect the telomeric, G-rich DNA from detection as a double-stranded DNA break, and yet still permit access to enzymes that process, replicate and maintain a sufficient reserve of telomeric DNA. When unable to maintain this equilibrium, erosion of telomeres leads to perturbations at or near the telomeres themselves, including loss of binding by the telomere protective complex, shelterin, and alterations in transcription and post-translational modifications of histones. Although the catastrophic consequences of full telomere de-protection are well described, recent evidence points to other, less obvious perturbations that arise when telomere length equilibrium is altered. For example, critically short telomeres also perturb DNA methylation and histone post-translational modifications at distal sites throughout the genome. In murine stem cells for example, this dysregulated chromatin leads to inappropriate suppression of pluripotency regulator factors such as Nanog. This review summarizes these recent findings, with an emphasis on how these genome-wide, telomere-induced perturbations can have profound consequences on cell function and fate. This article is part of the theme issue ‘Understanding diversity in telomere dynamics’.
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Affiliation(s)
- Lea Harrington
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, College of Science and Engineering, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JR, UK
| | - Fabio Pucci
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, College of Science and Engineering, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JR, UK
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40
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Roumelioti FM, Louizou E, Karras S, Neroutsou R, Velissariou V, Gagos S. Unbalanced X;9 translocation in an infertile male with de novo duplication Xp22.31p22.33. J Assist Reprod Genet 2019; 36:769-775. [PMID: 30675680 DOI: 10.1007/s10815-019-01405-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/09/2019] [Indexed: 12/12/2022] Open
Abstract
PURPOSE Male carriers of an X-autosome translocation are generally infertile, regardless of the position of the breakpoint on the X chromosome while the pathogenicity of Xp22.3 subtelomeric duplications is under debate. To shed light into this controversy, we present a rare case, of an azoospermic male with no other significant clinical findings, in whom classical cytogenetics revealed additional unbalanced chromosomal material, at the telomere of the long arm of one homolog of chromosome 9. METHODS In peripheral blood specimens of the index case and his parents, we performed GBanding, Inverted-DAPI Banding, AgNOR staining, Telomere specific Fluorescence in Situ Hybridization (FISH), Molecular karyotyping by Multi-color FISH, whole genome SNP microarrays, sub-telomeric MLPA, and transcription analysis of the expression of KAL1 gene by RT-PCR. RESULTS Multi-color FISH revealed an unbalanced translocation involving the short arm of chromosome X. SNP microarray analysis combined to classical cytogenetics and MLPA demonstrated a de novo 8.796 Mb duplication of Xp22.31-p22.33. Compared to three control specimens, the patient presented significantly elevated expression levels of KAL1 mRNA in peripheral blood, suggesting transcriptional functionality of the duplicated segment. CONCLUSIONS The duplicated segment contains the pseudo-autosomal region PAR1 and more than 30 genes including SHOX, ARSE, STS, KAL1, and FAM9A and is not listed as polymorphic. Our data advocate that duplications of the Xp22.3 region may not be associated with a clinical consequence.
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Affiliation(s)
- Fani-Marlen Roumelioti
- Laboratory of Genetics, Center of Experimental Medicine and Translational Research, Biomedical Research Foundation of the Academy of Athens, (BRFAA), Athens, Greece
| | - Eirini Louizou
- Department of Cytogenetics and Molecular Genetics, Bioiatriki, Group of Health Sciences, Athens, Greece
| | - Spyridon Karras
- Division of Endocrinology and Metabolism, First Department of Internal Medicine, Medical School, Aristotle University of Thessaloniki, AHEPA Hospital, Thessaloniki, Greece
| | - Rozalia Neroutsou
- Department of Cytogenetics and Molecular Genetics, Bioiatriki, Group of Health Sciences, Athens, Greece
| | - Voula Velissariou
- Department of Cytogenetics and Molecular Genetics, Bioiatriki, Group of Health Sciences, Athens, Greece
| | - Sarantis Gagos
- Laboratory of Genetics, Center of Experimental Medicine and Translational Research, Biomedical Research Foundation of the Academy of Athens, (BRFAA), Athens, Greece.
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Cacchione S, Biroccio A, Rizzo A. Emerging roles of telomeric chromatin alterations in cancer. J Exp Clin Cancer Res 2019; 38:21. [PMID: 30654820 PMCID: PMC6337846 DOI: 10.1186/s13046-019-1030-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 01/07/2019] [Indexed: 12/26/2022] Open
Abstract
Telomeres, the nucleoprotein structures that cap the ends of eukaryotic chromosomes, play important and multiple roles in tumorigenesis. Functional telomeres need the establishment of a protective chromatin structure based on the interplay between the specific complex named shelterin and a tight nucleosomal organization. Telomere shortening in duplicating somatic cells leads eventually to the destabilization of the telomere capping structure and to the activation of a DNA damage response (DDR) signaling. The final outcome of this process is cell replicative senescence, which constitute a protective barrier against unlimited proliferation. Cells that can bypass senescence checkpoint continue to divide until a second replicative checkpoint, crisis, characterized by chromosome fusions and rearrangements leading to massive cell death by apoptosis. During crisis telomere dysfunctions can either inhibit cell replication or favor tumorigenesis by the accumulation of chromosomal rearrangements and neoplastic mutations. The acquirement of a telomere maintenance mechanism allows fixing the aberrant phenotype, and gives the neoplastic cell unlimited replicative potential, one of the main hallmarks of cancer.Despite the crucial role that telomeres play in cancer development, little is known about the epigenetic alterations of telomeric chromatin that affect telomere protection and are associated with tumorigenesis. Here we discuss the current knowledge on the role of telomeric chromatin in neoplastic transformation, with a particular focus on H3.3 mutations in alternative lengthening of telomeres (ALT) cancers and sirtuin deacetylases dysfunctions.
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Affiliation(s)
- Stefano Cacchione
- Department of Biology and Biotechnology "Charles Darwin", Sapienza University of Roma, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Annamaria Biroccio
- Oncogenomic and Epigenetic Unit, IRCCS-Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy
| | - Angela Rizzo
- Oncogenomic and Epigenetic Unit, IRCCS-Regina Elena National Cancer Institute, Via Elio Chianesi 53, 00144, Rome, Italy.
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Telomeres in Plants and Humans: Not So Different, Not So Similar. Cells 2019; 8:cells8010058. [PMID: 30654521 PMCID: PMC6356271 DOI: 10.3390/cells8010058] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/07/2019] [Accepted: 01/07/2019] [Indexed: 01/01/2023] Open
Abstract
Parallel research on multiple model organisms shows that while some principles of telomere biology are conserved among all eukaryotic kingdoms, we also find some deviations that reflect different evolutionary paths and life strategies, which may have diversified after the establishment of telomerase as a primary mechanism for telomere maintenance. Much more than animals, plants have to cope with environmental stressors, including genotoxic factors, due to their sessile lifestyle. This is, in principle, made possible by an increased capacity and efficiency of the molecular systems ensuring maintenance of genome stability, as well as a higher tolerance to genome instability. Furthermore, plant ontogenesis differs from that of animals in which tissue differentiation and telomerase silencing occur during early embryonic development, and the “telomere clock” in somatic cells may act as a preventive measure against carcinogenesis. This does not happen in plants, where growth and ontogenesis occur through the serial division of apical meristems consisting of a small group of stem cells that generate a linear series of cells, which differentiate into an array of cell types that make a shoot and root. Flowers, as generative plant organs, initiate from the shoot apical meristem in mature plants which is incompatible with the human-like developmental telomere shortening. In this review, we discuss differences between human and plant telomere biology and the implications for aging, genome stability, and cell and organism survival. In particular, we provide a comprehensive comparative overview of telomere proteins acting in humans and in Arabidopsis thaliana model plant, and discuss distinct epigenetic features of telomeric chromatin in these species.
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43
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Andrałojć W, Małgowska M, Sarzyńska J, Pasternak K, Szpotkowski K, Kierzek R, Gdaniec Z. Unraveling the structural basis for the exceptional stability of RNA G-quadruplexes capped by a uridine tetrad at the 3' terminus. RNA (NEW YORK, N.Y.) 2019; 25:121-134. [PMID: 30341177 PMCID: PMC6298561 DOI: 10.1261/rna.068163.118] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/16/2018] [Indexed: 05/24/2023]
Abstract
Uridine tetrads (U-tetrads) are a structural element encountered in RNA G-quadruplexes, for example, in the structures formed by the biologically relevant human telomeric repeat RNA. For these molecules, an unexpectedly strong stabilizing influence of a U-tetrad forming at the 3' terminus of a quadruplex was reported. Here we present the high-resolution solution NMR structure of the r(UGGUGGU)4 quadruplex which, in our opinion, provides an explanation for this stabilization. Our structure features a distinctive, abrupt chain reversal just prior to the 3' uridine tetrad. Similar "reversed U-tetrads" were already observed in the crystalline phase. However, our NMR structure coupled with extensive explicit solvent molecular dynamics (MD) simulations identifies some key features of this motif that up to now remained overlooked. These include the presence of an exceptionally stable 2'OH to phosphate hydrogen bond, as well as the formation of an additional K+ binding pocket in the quadruplex groove.
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Affiliation(s)
- Witold Andrałojć
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Magdalena Małgowska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Joanna Sarzyńska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Karol Pasternak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Kamil Szpotkowski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Ryszard Kierzek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Zofia Gdaniec
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
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Nishihara H, Stanyon R, Kusumi J, Hirai H, Koga A. Evolutionary Origin of OwlRep, a Megasatellite DNA Associated with Adaptation of Owl Monkeys to Nocturnal Lifestyle. Genome Biol Evol 2018; 10:157-165. [PMID: 29294004 PMCID: PMC5765563 DOI: 10.1093/gbe/evx281] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2017] [Indexed: 12/14/2022] Open
Abstract
Rod cells of many nocturnal mammals have a “non-standard” nuclear architecture, which is called the inverted nuclear architecture. Heterochromatin localizes to the central region of the nucleus. This leads to an efficient light transmission to the outer segments of photoreceptors. Rod cells of diurnal mammals have the conventional nuclear architecture. Owl monkeys (genus Aotus) are the only taxon of simian primates that has a nocturnal or cathemeral lifestyle, and this adaptation is widely thought to be secondary. Their rod cells were shown to exhibit an intermediate chromatin distribution: a spherical heterochromatin block was found in the central region of the nucleus although it was less complete than that of typical nocturnal mammals. We recently demonstrated that the primary DNA component of this heterochromatin block was OwlRep, a megasatellite DNA consisting of 187-bp-long repeat units. However, the origin of OwlRep was not known. Here we show that OwlRep was derived from HSAT6, a simple repeat sequence found in the centromere regions of human chromosomes. HSAT6 occurs widely in primates, suggesting that it was already present in the last common ancestor of extant primates. Notably, Strepsirrhini and Tarsiformes apparently carry a single HSAT6 copy, whereas many species of Simiiformes contain multiple copies. Comparison of nucleotide sequences of these copies revealed the entire process of the OwlRep formation. HSAT6, with or without flanking sequences, was segmentally duplicated in New World monkeys. Then, in the owl monkey linage after its divergence from other New World monkeys, a copy of HSAT6 was tandemly amplified, eventually forming a megasatellite DNA.
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Affiliation(s)
- Hidenori Nishihara
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | | | - Junko Kusumi
- Faculty of Social and Cultural Studies, Kyushu University, Fukuoka, Japan
| | - Hirohisa Hirai
- Primate Research Institute, Kyoto University, Inuyama, Japan
| | - Akihiko Koga
- Primate Research Institute, Kyoto University, Inuyama, Japan
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45
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Sováková PP, Magdolenová A, Konečná K, Rájecká V, Fajkus J, Fojtová M. Telomere elongation upon transfer to callus culture reflects the reprogramming of telomere stability control in Arabidopsis. PLANT MOLECULAR BIOLOGY 2018; 98:81-99. [PMID: 30128721 DOI: 10.1007/s11103-018-0765-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 08/12/2018] [Indexed: 05/23/2023]
Abstract
KEY MESSAGE Standard pathways involved in the regulation of telomere stability do not contribute to gradual telomere elongation observed in the course of A. thaliana calli propagation. Genetic and epigenetic changes accompanying the culturing of plant cells have frequently been reported. Here we aimed to characterize the telomere homeostasis during long term callus propagation. While in Arabidopsis thaliana calli gradual telomere elongation was observed, telomeres were stable in Nicotiana tabacum and N. sylvestris cultures. Telomere elongation during callus propagation is thus not a general feature of plant cells. The long telomere phenotype in Arabidopsis calli was correlated neither with changes in telomerase activity nor with activation of alternative mechanisms of telomere elongation. The dynamics of telomere length changes was maintained in mutant calli with loss of function of important epigenetic modifiers but compromised in the presence of epigenetically active drug zebularine. To examine whether the cell culture-induced disruption of telomere homeostasis is associated with the modulated structure of chromosome ends, epigenetic properties of telomere chromatin were analysed. Albeit distinct changes in epigenetic modifications of telomere histones were observed, these were broadly stochastic. Our results show that contrary to animal cells, the structure and function of plant telomeres is not determined significantly by the epigenetic character of telomere chromatin. Set of differentially transcribed genes was identified in calli, but considering the known telomere- or telomerase-related functions of respective proteins, none of these changes per se was apparently related to the elongated telomere phenotype. Based on our data, we propose that the disruption in telomere homeostasis in Arabidopsis calli arises from the interplay of multiple factors, as a part of reprogramming of plant cells to long-term culture conditions.
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Affiliation(s)
- Pavla Polanská Sováková
- Laboratory of Functional Genomics and Proteomics, Faculty of Science, National Centre for Biomolecular Research, Masaryk University, 625 00, Brno, Czech Republic
| | - Alžbeta Magdolenová
- Laboratory of Functional Genomics and Proteomics, Faculty of Science, National Centre for Biomolecular Research, Masaryk University, 625 00, Brno, Czech Republic
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Prague, Czech Republic
| | - Klára Konečná
- Laboratory of Functional Genomics and Proteomics, Faculty of Science, National Centre for Biomolecular Research, Masaryk University, 625 00, Brno, Czech Republic
| | - Veronika Rájecká
- Laboratory of Functional Genomics and Proteomics, Faculty of Science, National Centre for Biomolecular Research, Masaryk University, 625 00, Brno, Czech Republic
| | - Jiří Fajkus
- Laboratory of Functional Genomics and Proteomics, Faculty of Science, National Centre for Biomolecular Research, Masaryk University, 625 00, Brno, Czech Republic
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, 625 00, Brno, Czech Republic
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., 612 65, Brno, Czech Republic
| | - Miloslava Fojtová
- Laboratory of Functional Genomics and Proteomics, Faculty of Science, National Centre for Biomolecular Research, Masaryk University, 625 00, Brno, Czech Republic.
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology (CEITEC), Masaryk University, 625 00, Brno, Czech Republic.
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46
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Gorgoulis VG, Pefani D, Pateras IS, Trougakos IP. Integrating the DNA damage and protein stress responses during cancer development and treatment. J Pathol 2018; 246:12-40. [PMID: 29756349 PMCID: PMC6120562 DOI: 10.1002/path.5097] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 04/16/2018] [Accepted: 05/08/2018] [Indexed: 12/11/2022]
Abstract
During evolution, cells have developed a wide spectrum of stress response modules to ensure homeostasis. The genome and proteome damage response pathways constitute the pillars of this interwoven 'defensive' network. Consequently, the deregulation of these pathways correlates with ageing and various pathophysiological states, including cancer. In the present review, we highlight: (1) the structure of the genome and proteome damage response pathways; (2) their functional crosstalk; and (3) the conditions under which they predispose to cancer. Within this context, we emphasize the role of oncogene-induced DNA damage as a driving force that shapes the cellular landscape for the emergence of the various hallmarks of cancer. We also discuss potential means to exploit key cancer-related alterations of the genome and proteome damage response pathways in order to develop novel efficient therapeutic modalities. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Vassilis G Gorgoulis
- Molecular Carcinogenesis Group, Department of Histology and Embryology, School of MedicineNational and Kapodistrian University of AthensAthensGreece
- Biomedical Research Foundation of the Academy of AthensAthensGreece
- Faculty of Biology, Medicine and HealthUniversity of Manchester, Manchester Academic Health Science CentreManchesterUK
| | - Dafni‐Eleftheria Pefani
- CRUK/MRC Institute for Radiation Oncology, Department of OncologyUniversity of OxfordOxfordUK
| | - Ioannis S Pateras
- Molecular Carcinogenesis Group, Department of Histology and Embryology, School of MedicineNational and Kapodistrian University of AthensAthensGreece
| | - Ioannis P Trougakos
- Department of Cell Biology and Biophysics, Faculty of BiologyNational and Kapodistrian University of AthensAthensGreece
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47
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Montero JJ, López-Silanes I, Megías D, F Fraga M, Castells-García Á, Blasco MA. TERRA recruitment of polycomb to telomeres is essential for histone trymethylation marks at telomeric heterochromatin. Nat Commun 2018; 9:1548. [PMID: 29670078 PMCID: PMC5906467 DOI: 10.1038/s41467-018-03916-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 03/20/2018] [Indexed: 11/18/2022] Open
Abstract
TERRAs are long non-coding RNAs generated from the telomeres. Lack of TERRA knockout models has hampered understanding TERRAs’ functions. We recently identified chromosome 20q as one of the main origins of human TERRAs, allowing us to generate the first 20q-TERRA knockout models and to demonstrate that TERRAs are essential for telomere length maintenance and protection. Here, we use ALT 20q-TERRA knockout cells to address a direct role of TERRAs in telomeric heterochromatin formation. We find that 20q-TERRAs are essential for the establishment of H3K9me3, H4K20me3, and H3K27me3 heterochromatin marks at telomeres. At the mechanistic level, we find that TERRAs bind to PRC2, responsible for catalyzing H3K27 tri-methylation, and that its localization to telomeres is TERRA-dependent. We further demonstrate that PRC2-dependent H3K27me3 at telomeres is required for the establishment of H3K9me3, H4K20me3, and HP1 binding at telomeres. Together, these findings demonstrate an important role for TERRAs in telomeric heterochromatin assembly. Long non-coding RNA TERRAs are essential for telomere protection and telomere length maintenance. Here the authors report a role for TERRAs in telomeric heterochromatin formation by recruiting Polycomb Repressive Complex 2 to telomeres.
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Affiliation(s)
- Juan J Montero
- Telomeres and Telomerase Group, Molecular Oncology Program, Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Isabel López-Silanes
- Telomeres and Telomerase Group, Molecular Oncology Program, Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Diego Megías
- Confocal Microscopy Unit, Spanish National Cancer Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Mario F Fraga
- Cancer Epigenetics Laboratory, Nanomaterials and Nanotechnology Research Center (CINN-CSIC)-Universidad de Oviedo, Institute of Oncology of Asturias (IUOPA) and Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Avda De la Vega, 4-6, 33940, El Entrego, Spain
| | - Álvaro Castells-García
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Drive Aiguader 88, 08003, Barcelona, Spain.,Universitat Pompeu Fabra (UPF), 08003, Barcelona, Spain
| | - Maria A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Melchor Fernández Almagro 3, E-28029, Madrid, Spain.
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48
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Fortuny A, Polo SE. The response to DNA damage in heterochromatin domains. Chromosoma 2018; 127:291-300. [PMID: 29594515 PMCID: PMC6440646 DOI: 10.1007/s00412-018-0669-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 03/18/2018] [Accepted: 03/19/2018] [Indexed: 10/24/2022]
Abstract
Eukaryotic genomes are organized into chromatin, divided into structurally and functionally distinct euchromatin and heterochromatin compartments. The high level of compaction and the abundance of repeated sequences in heterochromatin pose multiple challenges for the maintenance of genome stability. Cells have evolved sophisticated and highly controlled mechanisms to overcome these constraints. Here, we summarize recent findings on how the heterochromatic state influences DNA damage formation, signaling, and repair. By focusing on distinct heterochromatin domains in different eukaryotic species, we highlight the heterochromatin contribution to the compartmentalization of DNA damage repair in the cell nucleus and to the repair pathway choice. We also describe the diverse chromatin alterations associated with the DNA damage response in heterochromatin domains and present our current understanding of their regulatory mechanisms. Finally, we discuss the biological significance and the evolutionary conservation of these processes.
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Affiliation(s)
- Anna Fortuny
- Epigenetics and Cell Fate Centre, UMR7216 CNRS, Paris Diderot University, Paris, France
| | - Sophie E Polo
- Epigenetics and Cell Fate Centre, UMR7216 CNRS, Paris Diderot University, Paris, France.
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49
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Gomez-Escobar N, Almobadel N, Alzahrani O, Feichtinger J, Planells-Palop V, Alshehri Z, Thallinger GG, Wakeman JA, McFarlane RJ. Translin and Trax differentially regulate telomere-associated transcript homeostasis. Oncotarget 2017; 7:33809-20. [PMID: 27183912 PMCID: PMC5085120 DOI: 10.18632/oncotarget.9278] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 04/19/2016] [Indexed: 02/07/2023] Open
Abstract
Translin and Trax proteins are highly conserved nucleic acid binding proteins that have been implicated in RNA regulation in a range of biological processes including tRNA processing, RNA interference, microRNA degradation during oncogenesis, spermatogenesis and neuronal regulation. Here, we explore the function of this paralogue pair of proteins in the fission yeast. Using transcript analysis we demonstrate a reciprocal mechanism for control of telomere-associated transcripts. Mutation of tfx1+ (Trax) elevates transcript levels from silenced sub-telomeric regions of the genome, but not other silenced regions, such as the peri-centromeric heterochromatin. In the case of some sub-telomeric transcripts, but not all, this elevation is dependent on the Trax paralogue, Tsn1 (Translin). In a reciprocal fashion, Tsn1 (Translin) serves to repress levels of transcripts (TERRAs) from the telomeric repeats, whereas Tfx1 serves to maintain these elevated levels. This reveals a novel mechanism for the regulation of telomeric transcripts. We extend this to demonstrate that human Translin and Trax also control telomere-associated transcript levels in human cells in a telomere-specific fashion.
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Affiliation(s)
- Natalia Gomez-Escobar
- North West Cancer Research Institute, School of Medical Sciences, Bangor University, Bangor, Gwynedd, United Kingdom
| | - Nasser Almobadel
- North West Cancer Research Institute, School of Medical Sciences, Bangor University, Bangor, Gwynedd, United Kingdom
| | - Othman Alzahrani
- North West Cancer Research Institute, School of Medical Sciences, Bangor University, Bangor, Gwynedd, United Kingdom
| | - Julia Feichtinger
- Computational Biotechnology and Bioinformatics Group, Institute of Molecular Biotechnology, Graz University of Technology, Graz, Austria.,Omics Center Graz, BioTechMed Graz, Graz, Austria
| | - Vicente Planells-Palop
- North West Cancer Research Institute, School of Medical Sciences, Bangor University, Bangor, Gwynedd, United Kingdom
| | - Zafer Alshehri
- North West Cancer Research Institute, School of Medical Sciences, Bangor University, Bangor, Gwynedd, United Kingdom
| | - Gerhard G Thallinger
- Computational Biotechnology and Bioinformatics Group, Institute of Molecular Biotechnology, Graz University of Technology, Graz, Austria.,Omics Center Graz, BioTechMed Graz, Graz, Austria
| | - Jane A Wakeman
- North West Cancer Research Institute, School of Medical Sciences, Bangor University, Bangor, Gwynedd, United Kingdom
| | - Ramsay J McFarlane
- North West Cancer Research Institute, School of Medical Sciences, Bangor University, Bangor, Gwynedd, United Kingdom
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CTCF driven TERRA transcription facilitates completion of telomere DNA replication. Nat Commun 2017; 8:2114. [PMID: 29235471 PMCID: PMC5727389 DOI: 10.1038/s41467-017-02212-w] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 11/14/2017] [Indexed: 12/20/2022] Open
Abstract
Telomere repeat DNA forms a nucleo-protein structure that can obstruct chromosomal DNA replication, especially under conditions of replication stress. Transcription of telomere repeats can initiate at subtelomeric CTCF-binding sites to generate telomere repeat-encoding RNA (TERRA), but the role of transcription, CTCF, and TERRA in telomere replication is not known. Here, we have used CRISPR/Cas9 gene editing to mutate CTCF-binding sites at the putative start site of TERRA transcripts for a class of subtelomeres. Under replication stress, telomeres lacking CTCF-driven TERRA exhibit sister-telomere loss and upon entry into mitosis, exhibit the formation of ultra-fine anaphase bridges and micronuclei. Importantly, these phenotypes could be rescued by the forced transcription of TERRA independent of CTCF binding. Our findings indicate that subtelomeric CTCF facilitates telomeric DNA replication by promoting TERRA transcription. Our findings also demonstrate that CTCF-driven TERRA transcription acts in cis to facilitate telomere repeat replication and chromosome stability. TERRA RNA is involved in maintaining stability during telomere repeat replication. Here the authors, by using CRISPR/Cas9, mutate CTCF-binding sites at start site of TERRA transcripts and find that subtelomeric CTCF facilitates telomeric DNA replication by promoting TERRA transcription.
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