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Singh M, Raseley K, Perez AM, MacKenzie D, Kosiyatrakul ST, Desai S, Batista N, Guru N, Loomba KK, Abid HZ, Wang Y, Udo-Bellner L, Stout RF, Schildkraut CL, Xiao M, Zhang D. Elucidation of the molecular mechanism of the breakage-fusion-bridge (BFB) cycle using a CRISPR-dCas9 cellular model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.03.587951. [PMID: 38617299 PMCID: PMC11014597 DOI: 10.1101/2024.04.03.587951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Chromosome instability (CIN) is frequently observed in many tumors. The breakage-fusion-bridge (BFB) cycle has been proposed to be one of the main drivers of CIN during tumorigenesis and tumor evolution. However, the detailed mechanisms for the individual steps of the BFB cycle warrants further investigation. Here, we demonstrated that a nuclease-dead Cas9 (dCas9) coupled with a telomere-specific single-guide RNA (sgTelo) can be used to model the BFB cycle. First, we showed that targeting dCas9 to telomeres using sgTelo impeded DNA replication at telomeres and induced a pronounced increase of replication stress and DNA damage. Using Single-Molecule Telomere Assay via Optical Mapping (SMTA-OM), we investigated the genome-wide features of telomeres in the dCas9/sgTelo cells and observed a dramatic increase of chromosome end fusions, including fusion/ITS+ and fusion/ITS-.Consistently, we also observed an increase in the formation of dicentric chromosomes, anaphase bridges, and intercellular telomeric chromosome bridges (ITCBs). Utilizing the dCas9/sgTelo system, we uncovered many novel molecular and structural features of the ITCB and demonstrated that multiple DNA repair pathways are implicated in the formation of ITCBs. Our studies shed new light on the molecular mechanisms of the BFB cycle, which will advance our understanding of tumorigenesis, tumor evolution, and drug resistance.
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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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Catto LFB, Zanelatto LC, Donaires FS, de Carvalho VS, Santana BA, Pinto AL, Fantacini D, de Souza LEB, Fonseca NP, Telho BS, Ayrosa Madeira MI, Barbosa Pagnano KB, Firmato AB, Fagundes EM, Higashi M, Nunes EC, Traina F, Lobo de F. Pontes L, Rego EM, Calado RT. Telomeric repeat-containing RNA is dysregulated in acute myeloid leukemia. Blood Adv 2023; 7:7067-7078. [PMID: 37773887 PMCID: PMC10694524 DOI: 10.1182/bloodadvances.2023010658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 09/11/2023] [Accepted: 09/18/2023] [Indexed: 10/01/2023] Open
Abstract
TERRA (telomeric repeat-containing RNA) is a class of long noncoding RNAs transcribed from subtelomeric and telomeric regions. TERRA binds to the subtelomeric and telomeric DNA-forming R-loops (DNA-RNA hybrids), which are involved in telomere maintenance and telomerase function, but the role of TERRA in human cells is not well characterized. Here, we comprehensively investigated for the first time TERRA expression in primary human hematopoietic cells from an exploratory cohort of patients with acute myeloid leukemia (AML), patients with acute lymphoblastic leukemia (ALL), patients with telomere biology disorder (TBD), and healthy subjects. TERRA expression was repressed in primary human hematopoietic cells, including healthy donors, patients with ALL, and patients with TBD, irrespective of their telomere length, except for AML. A second cohort comprising 88 patients with AML showed that TERRA was overexpressed in an AML subgroup also characterized by higher R-loop formation, low TERT and RNAseH2 expression, and a paucity of somatic splicing factor mutations. Telomere length did not correlate with TERRA expression levels. To assess the role of TERRA R-loops in AML, we induced R-loop depletion by increasing RNAseH1 expression in 2 AML cell lines. Decreased TERRA R-loops in AML cell lines resulted in increased chemosensitivity to cytarabine. Our findings indicate that TERRA is uniformly repressed in primary human hematopoietic cells but abnormally expressed in an AML subset with low telomerase.
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Affiliation(s)
- Luiz Fernando B. Catto
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Leonardo C. Zanelatto
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Flavia S. Donaires
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Vinicius S. de Carvalho
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Bárbara A. Santana
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - André L. Pinto
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Daianne Fantacini
- Regional Blood Center, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Lucas Eduardo B. de Souza
- Regional Blood Center, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Natasha P. Fonseca
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Bruno S. Telho
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Maria Isabel Ayrosa Madeira
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | | | | | | | | | | | - Fabiola Traina
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Lorena Lobo de F. Pontes
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Eduardo M. Rego
- Department of Internal Medicine, University of São Paulo Medical School, São Paulo, Brazil
| | - Rodrigo T. Calado
- Department of Medical Imaging, Hematology, and Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
- Regional Blood Center, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
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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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Rivosecchi J, Cusanelli E. TERRA beyond cancer: the biology of telomeric repeat-containing RNAs in somatic and germ cells. FRONTIERS IN AGING 2023; 4:1224225. [PMID: 37636218 PMCID: PMC10448526 DOI: 10.3389/fragi.2023.1224225] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 07/31/2023] [Indexed: 08/29/2023]
Abstract
The telomeric noncoding RNA TERRA is a key component of telomeres and it is widely expressed in normal as well as cancer cells. In the last 15 years, several publications have shed light on the role of TERRA in telomere homeostasis and cell survival in cancer cells. However, only few studies have investigated the regulation or the functions of TERRA in normal tissues. A better understanding of the biology of TERRA in non-cancer cells may provide unexpected insights into how these lncRNAs are transcribed and operate in cells, and their potential role in physiological processes, such as aging, age-related pathologies, inflammatory processes and human genetic diseases. In this review we aim to discuss the findings that have advanced our understanding of the biology of TERRA using non-cancer mammalian cells as a model system.
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Affiliation(s)
- Julieta Rivosecchi
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology—CIBIO, University of Trento, Trento, Italy
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Córdova-Oriz I, Kohls G, Iglesias C, Polonio AM, Chico-Sordo L, Toribio M, Meseguer M, Varela E, Pellicer A, García-Velasco JA. A Randomized Controlled Intervention Trial with Danazol to Improve Telomeric and Fertility Parameters in Women with Diminished Ovarian Reserve: A Pilot Study. WOMEN'S HEALTH REPORTS (NEW ROCHELLE, N.Y.) 2023; 4:305-318. [PMID: 37476605 PMCID: PMC10354732 DOI: 10.1089/whr.2023.0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 06/07/2023] [Indexed: 07/22/2023]
Abstract
Background Most women who are treated at in vitro fertilization (IVF) clinics have trouble conceiving due to ovarian failure (OF), which seems to be associated to short telomeres and reduced or absent telomerase activity in their granulosa cells. Indeed, telomere pathways are involved in organ dysfunction. However, sexual steroids can stimulate the expression of the telomerase gene and have been successfully used to prevent telomere attrition. Thus, a strategy to improve IVF outcomes in women with OF could be telomerase reactivation using sexual steroids. Methods We conducted a double-blind, placebo-controlled study. Patients with diminished ovarian reserve were randomized to Danazol or placebo for 3 months. We included patients with normal ovarian reserve in the study as untreated controls. Patients and controls underwent several ovarian stimulations (OSs). Telomere and IVF parameters were assessed. Results We found that the mean telomere length in blood and the percentage of short and long telomeres were similar throughout the 3 months of treatment with Danazol. Remarkably, while the number of cells with one telomeric repeat-containing RNA (TERRA) focus decreased (p = 0.04) after the first month of Danazol treatment, the number of cells with 2 to 4 TERRA foci increased (p = 0.02). Regarding fertility, no differences were found in the antral follicle count. Interestingly, in OS performed after the trial, all Danazol-treated patients had a better MII oocyte rate compared to OS performed before the pilot study.EudraCT number: 2018-004400-19. Conclusions Danazol treatment seemed to affect telomere maintenance, since both the number of TERRA foci and the ratio of MII oocytes changed. However, further research is needed to confirm these results.
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Affiliation(s)
- Isabel Córdova-Oriz
- The Health Research Institute La Fe (IIS La Fe), IVI Foundation, Valencia, Spain
| | | | | | - Alba M. Polonio
- The Health Research Institute La Fe (IIS La Fe), IVI Foundation, Valencia, Spain
| | - Lucía Chico-Sordo
- The Health Research Institute La Fe (IIS La Fe), IVI Foundation, Valencia, Spain
| | | | - Marcos Meseguer
- The Health Research Institute La Fe (IIS La Fe), IVI Foundation, Valencia, Spain
- Laboratory of In Vitro Fertilization, IVIRMA Valencia, Valencia, Spain
| | - Elisa Varela
- The Health Research Institute La Fe (IIS La Fe), IVI Foundation, Valencia, Spain
- Department of Medical Specialties and Public Health, Rey Juan Carlos University, Madrid, Spain
| | - Antonio Pellicer
- The Health Research Institute La Fe (IIS La Fe), IVI Foundation, Valencia, Spain
- School of Medicine, Department of Obstetrics and Gynecology, University of Valencia, Valencia, Spain
- IVIRMA Rome, Rome, Italy
| | - Juan A. García-Velasco
- The Health Research Institute La Fe (IIS La Fe), IVI Foundation, Valencia, Spain
- IVIRMA Madrid, Madrid, Spain
- Department of Medical Specialties and Public Health, Rey Juan Carlos University, Madrid, Spain
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Savoca V, Rivosecchi J, Gaiatto A, Rossi A, Mosca R, Gialdini I, Zubovic L, Tebaldi T, Macchi P, Cusanelli E. TERRA stability is regulated by RALY and polyadenylation in a telomere-specific manner. Cell Rep 2023; 42:112406. [PMID: 37060569 DOI: 10.1016/j.celrep.2023.112406] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/25/2023] [Accepted: 03/31/2023] [Indexed: 04/16/2023] Open
Abstract
Telomeric repeat-containing RNA (TERRA) is a long non-coding RNA transcribed from telomeres that plays key roles in telomere maintenance. A fraction of TERRA is polyadenylated, and the presence of the poly(A) tail influences TERRA localization and stability. However, the mechanisms of TERRA biogenesis remain mostly elusive. Here, we show that the stability of TERRA transcripts is regulated by the RNA-binding protein associated with lethal yellow mutation (RALY). RALY depletion results in lower TERRA levels, impaired localization of TERRA at telomeres, and ultimately telomere damage. Importantly, we show that TERRA polyadenylation is telomere specific and that RALY preferentially stabilizes non-polyadenylated TERRA transcripts. Finally, we report that TERRA interacts with the poly(A)-binding protein nuclear 1 (PABPN1). Altogether, our results indicate that TERRA stability is regulated by the interplay between RALY and PABPN1, defined by the TERRA polyadenylation state. Our findings also suggest that different telomeres may trigger distinct TERRA-mediated responses.
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Affiliation(s)
- Valeria Savoca
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Julieta Rivosecchi
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Alice Gaiatto
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Annalisa Rossi
- Laboratory of Molecular and Cellular Neurobiology, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Riccardo Mosca
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Irene Gialdini
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Lorena Zubovic
- Laboratory of Molecular and Cellular Neurobiology, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy
| | - Toma Tebaldi
- Laboratory of RNA and Disease Data Science, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy; Section of Hematology, Department of Internal Medicine, Yale Comprehensive Cancer Center, Yale University School of Medicine, New Haven, CT, USA
| | - Paolo Macchi
- Laboratory of Molecular and Cellular Neurobiology, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy.
| | - Emilio Cusanelli
- Laboratory of Cell Biology and Molecular Genetics, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Povo, Italy.
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Clatterbuck Soper SF, Meltzer PS. ATRX/DAXX: Guarding the Genome against the Hazards of ALT. Genes (Basel) 2023; 14:genes14040790. [PMID: 37107548 PMCID: PMC10137841 DOI: 10.3390/genes14040790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 03/29/2023] Open
Abstract
Proliferating cells must enact a telomere maintenance mechanism to ensure genomic stability. In a subset of tumors, telomeres are maintained not by telomerase, but through a homologous recombination-based mechanism termed Alternative Lengthening of Telomeres or ALT. The ALT process is linked to mutations in the ATRX/DAXX/H3.3 histone chaperone complex. This complex is responsible for depositing non-replicative histone variant H3.3 at pericentric and telomeric heterochromatin but has also been found to have roles in ameliorating replication in repeat sequences and in promoting DNA repair. In this review, we will discuss ways in which ATRX/DAXX helps to protect the genome, and how loss of this complex allows ALT to take hold.
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Telomere Transcription in MLL-Rearranged Leukemia Cell Lines: Increased Levels of TERRA Associate with Lymphoid Lineage and Are Independent of Telomere Length and Ploidy. Biomedicines 2023; 11:biomedicines11030925. [PMID: 36979904 PMCID: PMC10046226 DOI: 10.3390/biomedicines11030925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/25/2023] [Accepted: 03/02/2023] [Indexed: 03/19/2023] Open
Abstract
Telomere transcription into telomeric repeat-containing RNA (TERRA) is an integral component of all aspects of chromosome end protection consisting of telomerase- or recombination-dependent telomere elongation, telomere capping, and the preservation of the (sub)telomeric heterochromatin structure. The chromatin modifier and transcriptional regulator MLL binds to telomeres and regulates TERRA transcription in telomere length homeostasis and response to telomere dysfunction. MLL fusion proteins (MLL-FPs), the product of MLL rearrangements in leukemia, also bind to telomeric chromatin. However, an effect on telomere transcription in MLL-rearranged (MLL-r) leukemia has not yet been evaluated. Here, we show increased UUAGGG repeat-containing RNA levels in MLL-r acute lymphoblastic leukemia (ALL) when compared to non-MLL-r ALL and myeloid leukemia. MLL rearrangements do not affect telomere length and UUAGGG repeat-containing RNA levels correlate with mean telomere length and reflect increased levels of TERRA. Furthermore, high levels of TERRA in MLL-r ALL occur in the presence of telomerase activity and are independent of ploidy, an underestimated source of variation on the overall transcriptome size in a cell. This MLL rearrangement-dependent and lymphoid lineage-associated increase in levels of TERRA supports a sustained telomere transcription by MLL-FPs that correlates with marked genomic stability previously reported in pediatric MLL-r ALL.
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Chen L, Zhang C, Ma W, Huang J, Zhao Y, Liu H. METTL3-mediated m6A modification stabilizes TERRA and maintains telomere stability. Nucleic Acids Res 2022; 50:11619-11634. [PMID: 36399511 PMCID: PMC9723618 DOI: 10.1093/nar/gkac1027] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 09/23/2022] [Accepted: 10/21/2022] [Indexed: 11/19/2022] Open
Abstract
Telomeric repeat-containing RNA (TERRA) is a type of long non-coding RNA transcribed from telomeres, and it forms R-loops by invasion into telomeric DNA. Since either an excessive or inadequate number of R-loops leads to telomere instability, the TERRA levels need to be delicately modulated. In this study, we found that m6A modification presents on the subtelomeric regions of TERRA and stabilizes it, and the loss of METTL3 impacts telomere stability. Mechanically, the m6A modification on TERRA is catalyzed by METTL3, recognized and stabilized by the m6A reader YTHDC1. Knockdown of either METTL3 or YTHDC1 enhances TERRA degradation. The m6A-modified TERRA forms R-loops and promotes homologous recombination which is essential for the alternative lengthening of telomeres (ALT) pathway in cancer cells. METTL3 depletion leads to R-loop reduction, telomere shortening and instability. Altogether, these findings reveal that METTL3 protects telomeres by catalyzing m6A modification on TERRA, indicating that inhibition or deletion of METTL3 is potentially a new avenue for ALT cancer therapy.
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Affiliation(s)
| | | | - Wenbin Ma
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Junjiu Huang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China
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11
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Choi BE, Lee HT. DNA-RNA hybrid G-quadruplex tends to form near the 3' end of telomere overhang. Biophys J 2022; 121:2962-2980. [PMID: 35769005 PMCID: PMC9388385 DOI: 10.1016/j.bpj.2022.06.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 01/14/2022] [Accepted: 06/24/2022] [Indexed: 11/25/2022] Open
Abstract
Telomeric repeat-containing RNA (TERRA) has been suggested to participate in telomere maintenance. TERRA consisting of UUAGGG repeats is capable of forming an intermolecular G-quadruplex (GQ) with single-stranded TTAGGG-repeat DNA in the telomere 3' overhang. To explore the structural features and potential functions of this DNA-RNA hybrid GQ (HGQ), we used single-molecule FRET to study the folding patterns of DNA with four to seven telomeric tandem repeats annealed with a short RNA consisting of two or five telomeric repeats. Our data highlight that RNA prefers to form DNA-RNA HGQ near the 3' end of telomeric DNA. Furthermore, the unfolding of secondary structures by a complementary C-rich sequence was observed for DNA GQ but not for DNA-RNA HGQ, which demonstrated the enhanced stability of the telomere 3' end via hybridization with RNA. These conformational and physical properties of telomeric DNA-RNA HGQ suggest that TERRA might limit access to the 3' end of the telomeric DNA overhang, which is known to be critical for the interaction with telomerase and other telomere-associated proteins.
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Affiliation(s)
- Bok-Eum Choi
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama
| | - Hui-Ting Lee
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama.
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12
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Telomeric Repeat-Containing RNA (TERRA): A Review of the Literature and First Assessment in Cutaneous T-Cell Lymphomas. Genes (Basel) 2022; 13:genes13030539. [PMID: 35328092 PMCID: PMC8953746 DOI: 10.3390/genes13030539] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 01/11/2023] Open
Abstract
Telomeric Repeat-containing RNA (TERRA) are long non-coding RNAs transcribed from telomeric DNA sequences from multiple chromosome ends. Major research efforts have been made to understand TERRA roles and functions in several physiological and pathological processes. We summarize herein available data regarding TERRA’s roles in human cells and we report the first investigation in cutaneous T-cells lymphomas (CTCL) using real-time PCR. Among the TERRA analysed, our data suggest a particular role for TERRA 16p downregulation and TERRA 11q upregulation in CTCL lymphomagenesis.
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13
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Xu X, Chen Z, Wu W, Tian X. Polyadenylated Telomeric Noncoding RNA Functions as a Pivotal Therapeutic Target of Anti-Ageing to Stabilize Telomere Length of Chromosomes Via Collaborating With Zscan4c. Front Pharmacol 2022; 12:822779. [PMID: 35222015 PMCID: PMC8863872 DOI: 10.3389/fphar.2021.822779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 12/27/2021] [Indexed: 02/05/2023] Open
Abstract
Telomeres are closely associated with the development of cell aging. Shortening or erosion of telomeres will cause cell mortality, suggesting that the maintenance of telomere integrity facilitates cell anti-senescence. However, the mechanism of how to keep the telomere length remains fragmentary. Here, we found that polyadenylated telomeric noncoding RNA (TERRA) can promote the self-renewal when overexpressed in mouse embryonic stem cells (mESCs), implying that TERRA with polyadenylation is critical for mESC maintenance. Further studies revealed that TERRA with a polyadenylated tail plays an important role in the sustenance of telomere length. High-throughput sequencing and quantitative real-time PCR show that zinc finger and SCAN domain containing 4C (Zscan4c) may be a potential target of TERRA. Zscan4c is negatively regulated by TERRA and collaborates with TERRA to stabilize the telomere length of chromosomes in mESCs. Our study not only identifies TERRA as a potential novel factor of telomere length regulation and uncovers the new molecular mechanism of cell anti-aging, but also indicates that Zscan4c could be a key therapeutic target candidate for therapy in dysfunctional chromosome diseases. These data will expand our understanding of the cell fate regulatory network and will be beneficial to drug discovery and theragnostics for antiaging and anticancer therapy in the future.
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Affiliation(s)
- Xiaojuan Xu
- Huaxi MR Research Centre (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology and National Clinical Research Center for Geriatrics, West China Hospital of Sichuan University, Chengdu, China.,School of Life Sciences, Hefei Normal University, Hefei, China
| | - Zhengju Chen
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Wei Wu
- School of Life Sciences, Anhui University, Hefei, China
| | - Xiaohe Tian
- School of Life Sciences, Hefei Normal University, Hefei, China
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14
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Sato S. Protein Chemical Modification Using Highly Reactive Species and Spatial Control of Catalytic Reactions. Chem Pharm Bull (Tokyo) 2022; 70:95-105. [PMID: 35110442 DOI: 10.1248/cpb.c21-00915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Protein bioconjugation has become an increasingly important research method for introducing artificial functions in to protein with various applications, including therapeutics and biomaterials. Due to its amphiphilic nature, only a few tyrosine residues are exposed on the protein surface. Therefore, tyrosine residue has attracted attention as suitable targets for site-specific modification, and it is the most studied amino acid residue for modification reactions other than lysine and cysteine residues. In this review, we present the progress of our tyrosine chemical modification studies over the past decade. We have developed several different catalytic approaches to selectively modify tyrosine residues using peroxidase, laccase, hemin, and ruthenium photocatalysts. In addition to modifying tyrosine residues by generating radical species through single-electron transfer, we have developed a histidine modification method that utilizes singlet oxygen generated by photosensitizers. These highly reactive chemical species selectively modify proteins in close proximity to the enzyme/catalyst. Taking advantage of the spatially controllable reaction fields, we have developed novel methods for site-specific antibody modification, detecting hotspots of oxidative stress, and target identification of bioactive molecules.
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Affiliation(s)
- Shinichi Sato
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University
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15
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Xu M, Chigumira T, Chen Z, Tones J, Zhao R, Dahl KN, Chenoweth DM, Zhang H. CRISPR Cas13-Based Tools to Track and Manipulate Endogenous Telomeric Repeat-Containing RNAs in Live Cells. Front Mol Biosci 2022; 8:785160. [PMID: 35174207 PMCID: PMC8841788 DOI: 10.3389/fmolb.2021.785160] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/22/2021] [Indexed: 12/23/2022] Open
Abstract
TERRA, TElomeric Repeat-containing RNA, is a long non-coding RNA transcribed from telomeres. Emerging evidence indicates that TERRA regulates telomere maintenance and chromosome end protection in normal and cancerous cells. However, the mechanism of how TERRA contributes to telomere functions is still unclear, partially owing to the shortage of approaches to track and manipulate endogenous TERRA molecules in live cells. Here, we developed a method to visualize TERRA in live cells via a combination of CRISPR Cas13 RNA labeling and SunTag technology. Single-particle tracking reveals that TERRA foci undergo anomalous diffusion in a manner that depends on the timescale and telomeric localization. Furthermore, we used a chemically-induced protein dimerization system to manipulate TERRA subcellular localization in live cells. Overall, our approaches to monitor and control TERRA locations in live cells provide powerful tools to better understand its roles in telomere maintenance and genomic integrity.
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Affiliation(s)
- Meng Xu
- Department of Biological Sciences, Mellon College of Science, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Tafadzwa Chigumira
- Department of Chemical Engineering, College of Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Ziheng Chen
- Department of Biological Sciences, Mellon College of Science, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Jason Tones
- Department of Biological Sciences, Mellon College of Science, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Rongwei Zhao
- Department of Biological Sciences, Mellon College of Science, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Kris Noel Dahl
- Department of Chemical Engineering, College of Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
| | - David M. Chenoweth
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, United States
| | - Huaiying Zhang
- Department of Biological Sciences, Mellon College of Science, Carnegie Mellon University, Pittsburgh, PA, United States
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16
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Lin J, Epel E. Stress and telomere shortening: Insights from cellular mechanisms. Ageing Res Rev 2022; 73:101507. [PMID: 34736994 PMCID: PMC8920518 DOI: 10.1016/j.arr.2021.101507] [Citation(s) in RCA: 100] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/08/2021] [Accepted: 10/21/2021] [Indexed: 12/14/2022]
Abstract
Short telomeres confer risk of degenerative diseases. Chronic psychological stress can lead to disease through many pathways, and research from in vitro studies to human longitudinal studies has pointed to stress-induced telomere damage as an important pathway. However, there has not been a comprehensive model to describe how changes in stress physiology and neuroendocrine pathways can lead to changes in telomere biology. Critically short telomeres or the collapse of the telomere structure caused by displacement of telomere binding protein complex shelterin elicit a DNA damage response and lead to senescence or apoptosis. In this narrative review, we summarize the key roles glucocorticoids, reactive oxygen species (ROS) and mitochondria, and inflammation play in mediating the relationship between psychological stress and telomere maintenance. We emphasis that these mediators are interconnected and reinforce each other in positive feedback loops. Telomere length has not been studied across the lifespan yet, but the initial setting point at birth appears to be the most influential point, as it sets the lifetime trajectory, and is influenced by stress. We describe two types of intergenerational stress effects on telomeres - prenatal stress effects on telomeres during fetal development, and 'telotype transmission" -the directly inherited transmission of short telomeres from parental germline. It is clear that the initial simplistic view of telomere length as a mitotic clock has evolved into a far more complex picture of both transgenerational telomere influences, and of interconnected molecular and cellular pathways and networks, as hallmarks of aging where telomere maintenance is a key player interacting with mitochondria. Further mechanistic investigations testing this comprehensive model of stress mediators shaping telomere biology and the telomere-mitochondrial nexus will lead to better understanding from cell to human lifespan aging, and could lead to anti-aging interventions.
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17
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Impact of Chromatin Dynamics and DNA Repair on Genomic Stability and Treatment Resistance in Pediatric High-Grade Gliomas. Cancers (Basel) 2021; 13:cancers13225678. [PMID: 34830833 PMCID: PMC8616465 DOI: 10.3390/cancers13225678] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/08/2021] [Accepted: 11/11/2021] [Indexed: 02/07/2023] Open
Abstract
Simple Summary Pediatric high-grade gliomas (pHGGs) are the leading cause of mortality in pediatric neuro-oncology, due in great part to treatment resistance driven by complex DNA repair mechanisms. pHGGs have recently been divided into molecular subtypes based on mutations affecting the N-terminal tail of the histone variant H3.3 and the ATRX/DAXX histone chaperone that deposits H3.3 at repetitive heterochromatin loci that are of paramount importance to the stability of our genome. This review addresses the functions of H3.3 and ATRX/DAXX in chromatin dynamics and DNA repair, as well as the impact of mutations affecting H3.3/ATRX/DAXX on treatment resistance and how the vulnerabilities they expose could foster novel therapeutic strategies. Abstract Despite their low incidence, pediatric high-grade gliomas (pHGGs), including diffuse intrinsic pontine gliomas (DIPGs), are the leading cause of mortality in pediatric neuro-oncology. Recurrent, mutually exclusive mutations affecting K27 (K27M) and G34 (G34R/V) in the N-terminal tail of histones H3.3 and H3.1 act as key biological drivers of pHGGs. Notably, mutations in H3.3 are frequently associated with mutations affecting ATRX and DAXX, which encode a chaperone complex that deposits H3.3 into heterochromatic regions, including telomeres. The K27M and G34R/V mutations lead to distinct epigenetic reprogramming, telomere maintenance mechanisms, and oncogenesis scenarios, resulting in distinct subgroups of patients characterized by differences in tumor localization, clinical outcome, as well as concurrent epigenetic and genetic alterations. Contrasting with our understanding of the molecular biology of pHGGs, there has been little improvement in the treatment of pHGGs, with the current mainstays of therapy—genotoxic chemotherapy and ionizing radiation (IR)—facing the development of tumor resistance driven by complex DNA repair pathways. Chromatin and nucleosome dynamics constitute important modulators of the DNA damage response (DDR). Here, we summarize the major DNA repair pathways that contribute to resistance to current DNA damaging agent-based therapeutic strategies and describe the telomere maintenance mechanisms encountered in pHGGs. We then review the functions of H3.3 and its chaperones in chromatin dynamics and DNA repair, as well as examining the impact of their mutation/alteration on these processes. Finally, we discuss potential strategies targeting DNA repair and epigenetic mechanisms as well as telomere maintenance mechanisms, to improve the treatment of pHGGs.
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18
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Forsyth RG, Krenács T, Athanasou N, Hogendoorn PCW. Cell Biology of Giant Cell Tumour of Bone: Crosstalk between m/wt Nucleosome H3.3, Telomeres and Osteoclastogenesis. Cancers (Basel) 2021; 13:5119. [PMID: 34680268 PMCID: PMC8534144 DOI: 10.3390/cancers13205119] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/06/2021] [Accepted: 10/08/2021] [Indexed: 12/14/2022] Open
Abstract
Giant cell tumour of bone (GCTB) is a rare and intriguing primary bone neoplasm. Worrisome clinical features are its local destructive behaviour, its high tendency to recur after surgical therapy and its ability to create so-called benign lung metastases (lung 'plugs'). GCTB displays a complex and difficult-to-understand cell biological behaviour because of its heterogenous morphology. Recently, a driver mutation in histone H3.3 was found. This mutation is highly conserved in GCTB but can also be detected in glioblastoma. Denosumab was recently introduced as an extra option of medical treatment next to traditional surgical and in rare cases, radiotherapy. Despite these new insights, many 'old' questions about the key features of GCTB remain unanswered, such as the presence of telomeric associations (TAs), the reactivation of hTERT, and its slight genomic instability. This review summarises the recent relevant literature of histone H3.3 in relation to the GCTB-specific G34W mutation and pays specific attention to the G34W mutation in relation to the development of TAs, genomic instability, and the characteristic morphology of GCTB. As pieces of an etiogenetic puzzle, this review tries fitting all these molecular features and the unique H3.3 G34W mutation together in GCTB.
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Affiliation(s)
- Ramses G. Forsyth
- Department of Pathology, University Hospital Brussels (UZB), Laarbeeklaan 101, 1090 Brussels, Belgium;
- Labaratorium for Experimental Pathology (EXPA), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Tibor Krenács
- 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllöi ut 26, 1085 Budapest, Hungary;
| | - Nicholas Athanasou
- Department of Histopathology, Nuffield Orthopaedic Centre, University of Oxford, NDORMS, Oxford OX3 7HE, UK;
| | - Pancras C. W. Hogendoorn
- Department of Pathology, University Hospital Brussels (UZB), Laarbeeklaan 101, 1090 Brussels, Belgium;
- Labaratorium for Experimental Pathology (EXPA), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
- 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllöi ut 26, 1085 Budapest, Hungary;
- Department of Histopathology, Nuffield Orthopaedic Centre, University of Oxford, NDORMS, Oxford OX3 7HE, UK;
- Department of Pathology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2300 RC Leiden, The Netherlands
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19
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Ide S, Sasaki A, Kawamoto Y, Bando T, Sugiyama H, Maeshima K. Telomere-specific chromatin capture using a pyrrole-imidazole polyamide probe for the identification of proteins and non-coding RNAs. Epigenetics Chromatin 2021; 14:46. [PMID: 34627342 PMCID: PMC8502363 DOI: 10.1186/s13072-021-00421-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 09/23/2021] [Indexed: 11/25/2022] Open
Abstract
Background Knowing chromatin components at a DNA regulatory element at any given time is essential for understanding how the element works during cellular proliferation, differentiation and development. A region-specific chromatin purification is an invaluable approach to dissecting the comprehensive chromatin composition at a particular region. Several methods (e.g., PICh, enChIP, CAPTURE and CLASP) have been developed for isolating and analyzing chromatin components. However, all of them have some shortcomings in identifying non-coding RNA associated with DNA regulatory elements. Results We have developed a new approach for affinity purification of specific chromatin segments employing an N-methyl pyrrole (P)-N-methylimidazole (I) (PI) polyamide probe, which binds to a specific sequence in double-stranded DNA via Watson–Crick base pairing as a minor groove binder. This new technique is called proteomics and RNA-omics of isolated chromatin segments (PI-PRICh). Using PI-PRICh to isolate mouse and human telomeric components, we found enrichments of shelterin proteins, the well-known telomerase RNA component (TERC) and telomeric repeat-containing RNA (TERRA). When PI-PRICh was performed for alternative lengthening of telomere (ALT) cells with highly recombinogenic telomeres, in addition to the conventional telomeric chromatin, we obtained chromatin regions containing telomeric repeat insertions scattered in the genome and their associated RNAs. Conclusion PI-PRICh reproducibly identified both the protein and RNA components of telomeric chromatin when targeting telomere repeats. PI polyamide is a promising alternative to simultaneously isolate associated proteins and RNAs of sequence-specific chromatin regions under native conditions, allowing better understanding of chromatin organization and functions within the cell. Supplementary Information The online version contains supplementary material available at 10.1186/s13072-021-00421-8.
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Affiliation(s)
- Satoru Ide
- Genome Dynamics Laboratory, National Institute of Genetics, ROIS, Mishima, Shizuoka, 411-8540, Japan. .,Department of Genetics, School of Life Science, SOKENDAI, Mishima, Shizuoka, 411-8540, Japan.
| | - Asuka Sasaki
- Genome Dynamics Laboratory, National Institute of Genetics, ROIS, Mishima, Shizuoka, 411-8540, Japan.,Department of Genetics, School of Life Science, SOKENDAI, Mishima, Shizuoka, 411-8540, Japan
| | - Yusuke Kawamoto
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto, 606-8502, Japan
| | - Toshikazu Bando
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto, 606-8502, Japan
| | - Hiroshi Sugiyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto, 606-8502, Japan
| | - Kazuhiro Maeshima
- Genome Dynamics Laboratory, National Institute of Genetics, ROIS, Mishima, Shizuoka, 411-8540, Japan.,Department of Genetics, School of Life Science, SOKENDAI, Mishima, Shizuoka, 411-8540, Japan
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20
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Novo CL. A Tale of Two States: Pluripotency Regulation of Telomeres. Front Cell Dev Biol 2021; 9:703466. [PMID: 34307383 PMCID: PMC8300013 DOI: 10.3389/fcell.2021.703466] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/08/2021] [Indexed: 01/01/2023] Open
Abstract
Inside the nucleus, chromatin is functionally organized and maintained as a complex three-dimensional network of structures with different accessibility such as compartments, lamina associated domains, and membraneless bodies. Chromatin is epigenetically and transcriptionally regulated by an intricate and dynamic interplay of molecular processes to ensure genome stability. Phase separation, a process that involves the spontaneous organization of a solution into separate phases, has been proposed as a mechanism for the timely coordination of several cellular processes, including replication, transcription and DNA repair. Telomeres, the repetitive structures at the end of chromosomes, are epigenetically maintained in a repressed heterochromatic state that prevents their recognition as double-strand breaks (DSB), avoiding DNA damage repair and ensuring cell proliferation. In pluripotent embryonic stem cells, telomeres adopt a non-canonical, relaxed epigenetic state, which is characterized by a low density of histone methylation and expression of telomere non-coding transcripts (TERRA). Intriguingly, this telomere non-canonical conformation is usually associated with chromosome instability and aneuploidy in somatic cells, raising the question of how genome stability is maintained in a pluripotent background. In this review, we will explore how emerging technological and conceptual developments in 3D genome architecture can provide novel mechanistic perspectives for the pluripotent epigenetic paradox at telomeres. In particular, as RNA drives the formation of LLPS, we will consider how pluripotency-associated high levels of TERRA could drive and coordinate phase separation of several nuclear processes to ensure genome stability. These conceptual advances will provide a better understanding of telomere regulation and genome stability within the highly dynamic pluripotent background.
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Affiliation(s)
- Clara Lopes Novo
- The Francis Crick Institute, London, United Kingdom
- Imperial College London, London, United Kingdom
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21
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Saha A, Gaurav AK, Pandya UM, Afrin M, Sandhu R, Nanavaty V, Schnur B, Li B. TbTRF suppresses the TERRA level and regulates the cell cycle-dependent TERRA foci number with a TERRA binding activity in its C-terminal Myb domain. Nucleic Acids Res 2021; 49:5637-5653. [PMID: 34048580 PMCID: PMC8191777 DOI: 10.1093/nar/gkab401] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/05/2021] [Accepted: 04/29/2021] [Indexed: 02/07/2023] Open
Abstract
Telomere repeat-containing RNA (TERRA) has been identified in multiple organisms including Trypanosoma brucei, a protozoan parasite that causes human African trypanosomiasis. T. brucei regularly switches its major surface antigen, VSG, to evade the host immune response. VSG is expressed exclusively from subtelomeric expression sites, and we have shown that telomere proteins play important roles in the regulation of VSG silencing and switching. In this study, we identify several unique features of TERRA and telomere biology in T. brucei. First, the number of TERRA foci is cell cycle-regulated and influenced by TbTRF, the duplex telomere DNA binding factor in T. brucei. Second, TERRA is transcribed by RNA polymerase I mainly from a single telomere downstream of the active VSG. Third, TbTRF binds TERRA through its C-terminal Myb domain, which also has the duplex DNA binding activity, in a sequence-specific manner and suppresses the TERRA level without affecting its half-life. Finally, levels of the telomeric R-loop and telomere DNA damage were increased upon TbTRF depletion. Overexpression of an ectopic allele of RNase H1 that resolves the R-loop structure in TbTRF RNAi cells can partially suppress these phenotypes, revealing an underlying mechanism of how TbTRF helps maintain telomere integrity.
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Affiliation(s)
- Arpita Saha
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Amit Kumar Gaurav
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Unnati M Pandya
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Marjia Afrin
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Ranjodh Sandhu
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Vishal Nanavaty
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Brittny Schnur
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Bibo Li
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA.,Case Comprehensive Cancer Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA.,Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA.,Center for RNA Science and Therapeutics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
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22
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DNA-RNA Hybrid (R-Loop): From a Unified Picture of the Mammalian Telomere to the Genome-Wide Profile. Cells 2021; 10:cells10061556. [PMID: 34205454 PMCID: PMC8233970 DOI: 10.3390/cells10061556] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/11/2021] [Accepted: 06/16/2021] [Indexed: 01/16/2023] Open
Abstract
Local three-stranded DNA/RNA hybrid regions of genomes (R-loops) have been detected either by binding of a monoclonal antibody (DRIP assay) or by enzymatic recognition by RNaseH. Such a structure has been postulated for mouse and human telomeres, clearly suggested by the identification of the complementary RNA Telomeric repeat-containing RNA “TERRA”. However, the tremendous disparity in the information obtained with antibody-based technology drove us to investigate a new strategy. Based on the observation that DNA/RNA hybrids in a triplex complex genome co-purify with the double-stranded chromosomal DNA fraction, we developed a direct preparative approach from total protein-free cellular extract without antibody that allows their physical isolation and determination of their RNA nucleotide sequence. We then define in the normal mouse and human sperm genomes the notion of stable DNA associated RNA terminal R-loop complexes, including TERRA molecules synthesized from local promoters of every chromosome. Furthermore, the first strong evidence of all telomeric structures, applied additionally to the whole murine sperm genome compared to the testes, showed reproducible R-loop complexes of the whole genome and suggesting a defined profile in the sperm genome for the next generation.
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23
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RTEL1 influences the abundance and localization of TERRA RNA. Nat Commun 2021; 12:3016. [PMID: 34021146 PMCID: PMC8140157 DOI: 10.1038/s41467-021-23299-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 04/22/2021] [Indexed: 12/13/2022] Open
Abstract
Telomere repeat containing RNAs (TERRAs) are a family of long non-coding RNAs transcribed from the subtelomeric regions of eukaryotic chromosomes. TERRA transcripts can form R-loops at chromosome ends; however the importance of these structures or the regulation of TERRA expression and retention in telomeric R-loops remain unclear. Here, we show that the RTEL1 (Regulator of Telomere Length 1) helicase influences the abundance and localization of TERRA in human cells. Depletion of RTEL1 leads to increased levels of TERRA RNA while reducing TERRA-containing R loops at telomeres. In vitro, RTEL1 shows a strong preference for binding G-quadruplex structures which form in TERRA. This binding is mediated by the C-terminal region of RTEL1, and is independent of the RTEL1 helicase domain. RTEL1 binding to TERRA appears to be essential for cell viability, underscoring the importance of this function. Degradation of TERRA-containing R-loops by overexpression of RNAse H1 partially recapitulates the increased TERRA levels and telomeric instability associated with RTEL1 deficiency. Collectively, these data suggest that regulation of TERRA is a key function of the RTEL1 helicase, and that loss of that function may contribute to the disease phenotypes of patients with RTEL1 mutations. Long non coding RNA TERRA transcripts can form R-loops at chromosome ends. Here, the authors reveal a role for the helicase RTEL in affecting TERRA levels and localization.
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24
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Viceconte N, Loriot A, Lona Abreu P, Scheibe M, Fradera Sola A, Butter F, De Smet C, Azzalin CM, Arnoult N, Decottignies A. PAR-TERRA is the main contributor to telomeric repeat-containing RNA transcripts in normal and cancer mouse cells. RNA (NEW YORK, N.Y.) 2021; 27:106-121. [PMID: 33127860 PMCID: PMC7749631 DOI: 10.1261/rna.076281.120] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 10/28/2020] [Indexed: 05/12/2023]
Abstract
Telomeric repeat-containing RNA (TERRA) molecules play important roles at telomeres, from heterochromatin regulation to telomerase activity control. In human cells, TERRA is transcribed from subtelomeric promoters located on most chromosome ends and associates with telomeres. The origin of mouse TERRA molecules is, however, unclear, as transcription from the pseudoautosomal PAR locus was recently suggested to account for the vast majority of TERRA in embryonic stem cells (ESC). Here, we confirm the production of TERRA from both the chromosome 18q telomere and the PAR locus in mouse embryonic fibroblasts, ESC, and various mouse cancer and immortalized cell lines, and we identify two novel sources of TERRA on mouse chromosome 2 and X. Using various approaches, we show that PAR-TERRA molecules account for the majority of TERRA transcripts, displaying an increase of two to four orders of magnitude compared to the telomeric 18q transcript. Finally, we present a SILAC-based pull-down screen revealing a large overlap between TERRA-interacting proteins in human and mouse cells, including PRC2 complex subunits, chromatin remodeling factors, DNA replication proteins, Aurora kinases, shelterin complex subunits, Bloom helicase, Coilin, and paraspeckle proteins. Hence, despite originating from distinct genomic regions, mouse and human TERRA are likely to play similar functions in cells.
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Affiliation(s)
- Nikenza Viceconte
- Genetic and Epigenetic Alterations of Genomes, de Duve Institute, Université catholique de Louvain (UCLouvain), 1200 Brussels, Belgium
| | - Axelle Loriot
- Genetic and Epigenetic Alterations of Genomes, de Duve Institute, Université catholique de Louvain (UCLouvain), 1200 Brussels, Belgium
| | - Patrícia Lona Abreu
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Marion Scheibe
- Quantitative Proteomics, Institute of Molecular Biology (IMB), 55128 Mainz, Germany
| | - Albert Fradera Sola
- Quantitative Proteomics, Institute of Molecular Biology (IMB), 55128 Mainz, Germany
| | - Falk Butter
- Quantitative Proteomics, Institute of Molecular Biology (IMB), 55128 Mainz, Germany
| | - Charles De Smet
- Genetic and Epigenetic Alterations of Genomes, de Duve Institute, Université catholique de Louvain (UCLouvain), 1200 Brussels, Belgium
| | - Claus M Azzalin
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Nausica Arnoult
- MCBD-University of Colorado Boulder, Boulder, Colorado 80309-0347, USA
| | - Anabelle Decottignies
- Genetic and Epigenetic Alterations of Genomes, de Duve Institute, Université catholique de Louvain (UCLouvain), 1200 Brussels, Belgium
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25
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Toubiana S, Larom G, Smoom R, Duszynski RJ, Godley LA, Francastel C, Velasco G, Selig S. Regulation of telomeric function by DNA methylation differs between humans and mice. Hum Mol Genet 2020; 29:3197-3210. [PMID: 32916696 DOI: 10.1093/hmg/ddaa206] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 11/13/2022] Open
Abstract
The most distal 2 kb region in the majority of human subtelomeres contains CpG-rich promoters for TERRA, a long non-coding RNA. When the function of the de novo DNA methyltransferase DNMT3B is disrupted, as in ICF1 syndrome, subtelomeres are abnormally hypomethylated, subtelomeric heterochromatin acquires open chromatin characteristics, TERRA is highly expressed, and telomeres shorten rapidly. In this study, we explored whether the regulation of subtelomeric epigenetic characteristics by DNMT3B is conserved between humans and mice. Studying the DNA sequence of the distal 30 kb of the majority of murine q-arm subtelomeres indicated that these regions are relatively CpG-poor and do not contain TERRA promoters similar to those present in humans. Despite the lack of human-like TERRA promoters, we clearly detected TERRA expression originating from at least seven q-arm subtelomeres, and at higher levels in mouse pluripotent stem cells in comparison with mouse embryonic fibroblasts (MEFs). However, these differences in TERRA expression could not be explained by differential methylation of CpG islands present in the TERRA-expressing murine subtelomeres. To determine whether Dnmt3b regulates the expression of TERRA in mice, we characterized subtelomeric methylation and associated telomeric functions in cells derived from ICF1 model mice. Littermate-derived WT and ICF1 MEFs demonstrated no significant differences in subtelomeric DNA methylation, chromatin modifications, TERRA expression levels, telomere sister chromatid exchange or telomere length. We conclude that the epigenetic characteristics of murine subtelomeres differ substantially from their human counterparts and that TERRA transcription in mice is regulated by factors others than Dnmt3b.
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Affiliation(s)
- Shir Toubiana
- Department of Genetics, Rappaport Faculty of Medicine and Research Institute, Technion, Haifa 31096, Israel
| | - Gal Larom
- Department of Genetics, Rappaport Faculty of Medicine and Research Institute, Technion, Haifa 31096, Israel
| | - Riham Smoom
- Department of Genetics, The Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Robert J Duszynski
- Department of Medicine, Section of Hematology Oncology, The University of Chicago, Chicago 60637, USA
| | - Lucy A Godley
- Department of Medicine, Section of Hematology Oncology, The University of Chicago, Chicago 60637, USA
| | - Claire Francastel
- Université de Paris, Epigénétique et Destin Cellulaire, CNRS, Paris 75013, France
| | - Guillaume Velasco
- Université de Paris, Epigénétique et Destin Cellulaire, CNRS, Paris 75013, France
| | - Sara Selig
- Department of Genetics, Rappaport Faculty of Medicine and Research Institute, Technion, Haifa 31096, Israel
- Laboratory of Molecular Medicine, Rambam Health Care Campus, Haifa 31096, Israel
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26
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Berlyoung AS, Armitage BA. Assembly and Characterization of RNA/DNA Hetero-G-Quadruplexes. Biochemistry 2020; 59:4072-4080. [PMID: 33048532 DOI: 10.1021/acs.biochem.0c00657] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Transient association of guanine-rich RNA and DNA in the form of hetero-G-quadruplexes (RDQs) has emerged as an important mechanism for regulating genome transcription and replication but relatively little is known about the structure and biophysical properties of RDQs compared with DNA and RNA homo-G-quadruplexes. Herein, we report the assembly and characterization of three RDQs based on sequence motifs found in human telomeres and mitochondrial nucleic acids. Stable RDQs were assembled using a duplex scaffold, which prevented segregation of the DNA and RNA strands into separate homo-GQs. Each of the RDQs exhibited UV melting temperatures above 50 °C in 100 mM KCl and predominantly parallel morphologies, evidently driven by the RNA component. The fluorogenic dye thioflavin T binds to each RDQ with low micromolar KD values, similar to its binding to RNA and DNA homo-GQs. These results establish a method for assembling RDQs that should be amenable to screening compounds and libraries to identify selective RDQ-binding small molecules, oligonucleotides, and proteins.
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Affiliation(s)
- April S Berlyoung
- Department of Chemistry and Center for Nucleic Acids Science and Technology, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Bruce A Armitage
- Department of Chemistry and Center for Nucleic Acids Science and Technology, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
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Aguado J, d’Adda di Fagagna F, Wolvetang E. Telomere transcription in ageing. Ageing Res Rev 2020; 62:101115. [PMID: 32565330 DOI: 10.1016/j.arr.2020.101115] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/05/2020] [Accepted: 06/11/2020] [Indexed: 02/08/2023]
Abstract
Telomeres, the ends of eukaryotic chromosomes, play a central role in the control of cellular senescence and organismal ageing and need to be protected in order to avoid being recognised as damaged DNA and activate DNA damage response pathways. Dysfunctional telomeres arise from critically short telomeres or altered telomere structures, which ultimately lead to replicative cellular senescence and chromosome instability: both hallmarks of ageing. The observation that telomeres are transcribed led to the discovery that telomeric transcripts play important roles in chromosome end protection and genome stability maintenance. Recent evidence indicates that particular long non-coding (nc)RNAs transcribed at telomeres, namely TElomeric Repeat-containing RNA (TERRA) and telomeric damage-induced long ncRNAs (tdilncRNA), play key roles in age-related pathways by actively orchestrating the mechanisms known to regulate telomere length, chromosome end protection and DNA damage signalling. Here, we provide a comprehensive overview of the telomere transcriptome, outlining how it functions as a regulatory platform with essential functions in safeguarding telomere integrity and stability. We next review emerging antisense oligonucleotides therapeutic strategies that target telomeric ncRNAs and discuss their potential for ameliorating ageing and age-related diseases. Altogether, this review provides insights on the biological relevance of telomere transcription mechanisms in human ageing physiology and pathology.
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28
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Kordowitzki P, López de Silanes I, Guío-Carrión A, Blasco MA. Dynamics of telomeric repeat-containing RNA expression in early embryonic cleavage stages with regards to maternal age. Aging (Albany NY) 2020; 12:15906-15917. [PMID: 32860669 PMCID: PMC7485725 DOI: 10.18632/aging.103922] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 07/21/2020] [Indexed: 12/11/2022]
Abstract
Telomeres are transcribed into long non-coding RNAs known as Telomeric Repeat-Containing RNA (TERRA). They have been shown to be essential regulators of telomeres and to act as epigenomic modulators at extra-telomeric sites. However the role of TERRA during early embryonic development has never been investigated. Here, we show that TERRA is expressed in murine and bovine early development following a wave pattern. It starts at 4-cell stage, reaching a maximum at the 16-cell followed by a decline at the morula and blastocyst stages. Moreover, TERRA expression is not affected by increasing oocyte donor age whereas telomere length does. This indicates that TERRA expression is independent of the telomere length in early development. Our findings anticipate an essential role of TERRA in early stages of development and this might be useful in the future for a better understanding of age related female infertility.
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Affiliation(s)
- Paweł Kordowitzki
- Institute of Animal Reproduction and Food Research of Polish Academy of Sciences, Olsztyn, Poland.,Institute for Veterinary Medicine, Nicolaus Copernicus University, Torun, Poland
| | - Isabel López de Silanes
- Telomeres and Telomerase Group, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Ana Guío-Carrión
- Telomeres and Telomerase Group, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Maria A Blasco
- Telomeres and Telomerase Group, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
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29
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Fernandes SG, Dsouza R, Pandya G, Kirtonia A, Tergaonkar V, Lee SY, Garg M, Khattar E. Role of Telomeres and Telomeric Proteins in Human Malignancies and Their Therapeutic Potential. Cancers (Basel) 2020; 12:E1901. [PMID: 32674474 PMCID: PMC7409176 DOI: 10.3390/cancers12071901] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 12/19/2022] Open
Abstract
Telomeres are the ends of linear chromosomes comprised of repetitive nucleotide sequences in humans. Telomeres preserve chromosomal stability and genomic integrity. Telomere length shortens with every cell division in somatic cells, eventually resulting in replicative senescence once telomere length becomes critically short. Telomere shortening can be overcome by telomerase enzyme activity that is undetectable in somatic cells, while being active in germline cells, stem cells, and immune cells. Telomeres are bound by a shelterin complex that regulates telomere lengthening as well as protects them from being identified as DNA damage sites. Telomeres are transcribed by RNA polymerase II, and generate a long noncoding RNA called telomeric repeat-containing RNA (TERRA), which plays a key role in regulating subtelomeric gene expression. Replicative immortality and genome instability are hallmarks of cancer and to attain them cancer cells exploit telomere maintenance and telomere protection mechanisms. Thus, understanding the role of telomeres and their associated proteins in cancer initiation, progression and treatment is very important. The present review highlights the critical role of various telomeric components with recently established functions in cancer. Further, current strategies to target various telomeric components including human telomerase reverse transcriptase (hTERT) as a therapeutic approach in human malignancies are discussed.
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Affiliation(s)
- Stina George Fernandes
- Sunandan Divatia School of Science, SVKM’s NMIMS (Deemed to be University), Vile Parle West, Mumbai 400056, India; (S.G.F.); (R.D.)
| | - Rebecca Dsouza
- Sunandan Divatia School of Science, SVKM’s NMIMS (Deemed to be University), Vile Parle West, Mumbai 400056, India; (S.G.F.); (R.D.)
| | - Gouri Pandya
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Noida 201313, India; (G.P.); (A.K.)
| | - Anuradha Kirtonia
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Noida 201313, India; (G.P.); (A.K.)
| | - Vinay Tergaonkar
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore; (V.T.); (S.Y.L.)
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117597, Singapore
- Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore 117597, Singapore
| | - Sook Y. Lee
- Laboratory of NF-κB Signaling, Institute of Molecular and Cell Biology (IMCB), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore; (V.T.); (S.Y.L.)
| | - Manoj Garg
- Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University Uttar Pradesh, Noida 201313, India; (G.P.); (A.K.)
| | - Ekta Khattar
- Sunandan Divatia School of Science, SVKM’s NMIMS (Deemed to be University), Vile Parle West, Mumbai 400056, India; (S.G.F.); (R.D.)
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30
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Barral A, Déjardin J. Telomeric Chromatin and TERRA. J Mol Biol 2020; 432:4244-4256. [DOI: 10.1016/j.jmb.2020.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 03/03/2020] [Accepted: 03/03/2020] [Indexed: 01/01/2023]
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31
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Brieño-Enríquez MA, Moak SL, Abud-Flores A, Cohen PE. Characterization of telomeric repeat-containing RNA (TERRA) localization and protein interactions in primordial germ cells of the mouse†. Biol Reprod 2020; 100:950-962. [PMID: 30423030 DOI: 10.1093/biolre/ioy243] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 09/10/2018] [Accepted: 11/09/2018] [Indexed: 12/18/2022] Open
Abstract
Telomeres are dynamic nucleoprotein structures capping the physical ends of linear eukaryotic chromosomes. They consist of telomeric DNA repeats (TTAGGG), the shelterin protein complex, and telomeric repeat-containing RNA (TERRA). Proposed TERRA functions are wide ranging and include telomere maintenance, telomerase inhibition, genomic stability, and alternative lengthening of telomere. However, the presence and role of TERRA in primordial germ cells (PGCs), the embryonic precursors of germ cells, is unknown. Using RNA-fluorescence in situ hybridization, we identify TERRA transcripts in female PGCs at 11.5, 12.5, and 13.5 days postcoitum. In male PGCs, the earliest detection TERRA was at 12.5 dpc where we observed cells with either zero or one TERRA focus. Using qRT-PCR, we evaluated chromosome-specific TERRA expression. Female PGCs showed TERRA expression at 11.5 dpc from eight different chromosome subtelomeric regions (chromosomes 1, 2, 7, 9, 11, 13, 17, and 18) while in male PGCs, TERRA expression was confined to the chromosome 17. Most TERRA transcription in 13.5 dpc male PGCs arose from chromosomes 2 and 6. TERRA interacting proteins were evaluated using identification of direct RNA interacting proteins (iDRiP), which identified 48 in female and 26 in male protein interactors from PGCs at 13.5 dpc. We validated two different proteins: the splicing factor, proline- and glutamine-rich (SFPQ) in PGCs and non-POU domain-containing octamer-binding protein (NONO) in somatic cells. Taken together, our data indicate that TERRA expression and interactome during PGC development are regulated in a dynamic fashion that is dependent on gestational age and sex.
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Affiliation(s)
- Miguel A Brieño-Enríquez
- Department of Biomedical Sciences and the Cornell Center for Reproductive Genomics, Cornell University, Ithaca, New York, USA
| | - Steffanie L Moak
- Department of Biomedical Sciences and the Cornell Center for Reproductive Genomics, Cornell University, Ithaca, New York, USA
| | - Anyul Abud-Flores
- Department of Biomedical Sciences and the Cornell Center for Reproductive Genomics, Cornell University, Ithaca, New York, USA
| | - Paula E Cohen
- Department of Biomedical Sciences and the Cornell Center for Reproductive Genomics, Cornell University, Ithaca, New York, USA
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32
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Toufektchan E, Lejour V, Durand R, Giri N, Draskovic I, Bardot B, Laplante P, Jaber S, Alter BP, Londono-Vallejo JA, Savage SA, Toledo F. Germline mutation of MDM4, a major p53 regulator, in a familial syndrome of defective telomere maintenance. SCIENCE ADVANCES 2020; 6:eaay3511. [PMID: 32300648 PMCID: PMC7148086 DOI: 10.1126/sciadv.aay3511] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 01/16/2020] [Indexed: 05/08/2023]
Abstract
Dyskeratosis congenita is a cancer-prone inherited bone marrow failure syndrome caused by telomere dysfunction. A mouse model recently suggested that p53 regulates telomere metabolism, but the clinical relevance of this finding remained uncertain. Here, a germline missense mutation of MDM4, a negative regulator of p53, was found in a family with features suggestive of dyskeratosis congenita, e.g., bone marrow hypocellularity, short telomeres, tongue squamous cell carcinoma, and acute myeloid leukemia. Using a mouse model, we show that this mutation (p.T454M) leads to increased p53 activity, decreased telomere length, and bone marrow failure. Variations in p53 activity markedly altered the phenotype of Mdm4 mutant mice, suggesting an explanation for the variable expressivity of disease symptoms in the family. Our data indicate that a germline activation of the p53 pathway may cause telomere dysfunction and point to polymorphisms affecting this pathway as potential genetic modifiers of telomere biology and bone marrow function.
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Affiliation(s)
- Eléonore Toufektchan
- Genetics of Tumor Suppression, Institut Curie, Paris, France
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
| | - Vincent Lejour
- Genetics of Tumor Suppression, Institut Curie, Paris, France
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
| | - Romane Durand
- Genetics of Tumor Suppression, Institut Curie, Paris, France
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
| | - Neelam Giri
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA
| | - Irena Draskovic
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
- Telomeres and Cancer, Institut Curie, Paris, France
| | - Boris Bardot
- Genetics of Tumor Suppression, Institut Curie, Paris, France
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
| | - Pierre Laplante
- Genetics of Tumor Suppression, Institut Curie, Paris, France
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
| | - Sara Jaber
- Genetics of Tumor Suppression, Institut Curie, Paris, France
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
| | - Blanche P. Alter
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA
| | - José-Arturo Londono-Vallejo
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
- Telomeres and Cancer, Institut Curie, Paris, France
| | - Sharon A. Savage
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA
| | - Franck Toledo
- Genetics of Tumor Suppression, Institut Curie, Paris, France
- CNRS UMR 3244, Paris, France
- Sorbonne Université, Paris, France
- PSL Research University, Paris, France
- Corresponding author.
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33
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Galigniana NM, Charó NL, Uranga R, Cabanillas AM, Piwien-Pilipuk G. Oxidative stress induces transcription of telomeric repeat-containing RNA (TERRA) by engaging PKA signaling and cytoskeleton dynamics. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118643. [DOI: 10.1016/j.bbamcr.2020.118643] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 12/27/2019] [Accepted: 01/02/2020] [Indexed: 12/11/2022]
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Rossi M, Gorospe M. Noncoding RNAs Controlling Telomere Homeostasis in Senescence and Aging. Trends Mol Med 2020; 26:422-433. [PMID: 32277935 DOI: 10.1016/j.molmed.2020.01.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 12/23/2019] [Accepted: 01/21/2020] [Indexed: 12/12/2022]
Abstract
Aging is a universal and time-dependent biological decline associated with progressive deterioration of cells, tissues, and organs. Age-related decay can eventually lead to pathology such as cardiovascular and neurodegenerative diseases, cancer, and diabetes. A prominent molecular process underlying aging is the progressive shortening of telomeres, the structures that protect the ends of chromosomes, eventually triggering cellular senescence. Noncoding (nc)RNAs are emerging as major regulators of telomere length homeostasis. In this review, we describe the impact of ncRNAs on telomere function and discuss their implications in senescence and age-related diseases. We discuss emerging therapeutic strategies targeting telomere-regulatory ncRNAs in aging pathology.
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Affiliation(s)
- Martina Rossi
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA.
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35
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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: 126] [Impact Index Per Article: 31.5] [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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Lalonde M, Chartrand P. TERRA, a Multifaceted Regulator of Telomerase Activity at Telomeres. J Mol Biol 2020; 432:4232-4243. [PMID: 32084415 DOI: 10.1016/j.jmb.2020.02.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 02/06/2020] [Accepted: 02/10/2020] [Indexed: 02/07/2023]
Abstract
In eukaryotes, telomeres are repetitive sequences at the end of chromosomes, which are maintained in a constitutive heterochromatin state. It is now known that telomeres can be actively transcribed, leading to the production of a telomeric repeat-containing noncoding RNA called TERRA. Due to its sequence complementarity to the telomerase template, it was suggested early on that TERRA could be an inhibitor of telomerase. Since then, TERRA has been shown to be involved in heterochromatin formation at telomeres, to invade telomeric dsDNA and form R-loops, and even to promote telomerase recruitment at short telomeres. All these functions depend on the diverse capacities of this lncRNA to bind various cofactors, act as a scaffold, and promote higher-order complexes in cells. In this review, it will be highlighted as to how these properties of TERRA work together to regulate telomerase activity at telomeres.
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Affiliation(s)
- Maxime Lalonde
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Quebec, Canada
| | - Pascal Chartrand
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Quebec, Canada.
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37
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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: 18] [Impact Index Per Article: 4.5] [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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38
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Porreca RM, Herrera-Moyano E, Skourti E, Law PP, Gonzalez Franco R, Montoya A, Faull P, Kramer H, Vannier JB. TRF1 averts chromatin remodelling, recombination and replication dependent-break induced replication at mouse telomeres. eLife 2020; 9:49817. [PMID: 31934863 PMCID: PMC6986873 DOI: 10.7554/elife.49817] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 01/11/2020] [Indexed: 12/29/2022] Open
Abstract
Telomeres are a significant challenge to DNA replication and are prone to replication stress and telomere fragility. The shelterin component TRF1 facilitates telomere replication but the molecular mechanism remains uncertain. By interrogating the proteomic composition of telomeres, we show that mouse telomeres lacking TRF1 undergo protein composition reorganisation associated with the recruitment of DNA damage response and chromatin remodellers. Surprisingly, mTRF1 suppresses the accumulation of promyelocytic leukemia (PML) protein, BRCA1 and the SMC5/6 complex at telomeres, which is associated with increased Homologous Recombination (HR) and TERRA transcription. We uncovered a previously unappreciated role for mTRF1 in the suppression of telomere recombination, dependent on SMC5 and also POLD3 dependent Break Induced Replication at telomeres. We propose that TRF1 facilitates S-phase telomeric DNA synthesis to prevent illegitimate mitotic DNA recombination and chromatin rearrangement.
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Affiliation(s)
- Rosa Maria Porreca
- Telomere Replication and 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
| | - Emilia Herrera-Moyano
- Telomere Replication and 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
| | - Eleni Skourti
- Telomere Replication and 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
| | - Pui Pik Law
- Telomere Replication and 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
| | - Roser Gonzalez Franco
- Telomere Replication and 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
| | - Alex Montoya
- Biological Mass Spectrometry and Proteomics, Medical Research Council - London Institute of Medical Sciences, London, United Kingdom
| | - Peter Faull
- Biological Mass Spectrometry and Proteomics, Medical Research Council - London Institute of Medical Sciences, London, United Kingdom.,The Francis Crick Institute, Proteomics Mass Spectrometry Science and Technology Platform, London, United Kingdom
| | - Holger Kramer
- Biological Mass Spectrometry and Proteomics, Medical Research Council - London Institute of Medical Sciences, London, United Kingdom
| | - Jean-Baptiste Vannier
- Telomere Replication and 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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39
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Abstract
Stress exposure can leave long-term footprints within the organism, like in telomeres (TLs), protective chromosome caps that shorten during cell replication and following exposure to stressors. Short TLs are considered to indicate lower fitness prospects, but why TLs shorten under stressful conditions is not understood. Glucocorticoid hormones (GCs) increase upon stress exposure and are thought to promote TL shortening by increasing oxidative damage. However, evidence that GCs are pro-oxidants and oxidative stress is causally linked to TL attrition is mixed . Based on new biochemical findings, we propose the metabolic telomere attrition hypothesis: during times of substantially increased energy demands, TLs are shortened as part of the transition into an organismal 'emergency state', which prioritizes immediate survival functions over processes with longer-term benefits. TL attrition during energy shortages could serve multiple roles including amplified signalling of cellular energy debt to re-direct critical resources to immediately important processes. This new view of TL shortening as a strategy to resolve major energetic trade-offs can improve our understanding of TL dynamics. We suggest that TLs are master regulators of cell homeostasis and propose future research avenues to understand the interactions between energy homeostasis, metabolic regulators and TL.
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Affiliation(s)
- Stefania Casagrande
- 1 Research Group Evolutionary Physiology, Max Planck Institute for Ornithology , 82319 Seewiesen , Germany
| | - Michaela Hau
- 1 Research Group Evolutionary Physiology, Max Planck Institute for Ornithology , 82319 Seewiesen , Germany.,2 Department of Biology, University of Konstanz , D-78457 Konstanz , Germany
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40
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Oh BK, Choi Y, Bae J, Lee WM, Hoh JK, Choi JS. Increased amounts and stability of telomeric repeat-containing RNA (TERRA) following DNA damage induced by etoposide. PLoS One 2019; 14:e0225302. [PMID: 31756221 PMCID: PMC6874320 DOI: 10.1371/journal.pone.0225302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 11/01/2019] [Indexed: 11/25/2022] Open
Abstract
Telomeric repeat-containing RNAs (TERRAs) are long noncoding RNAs transcribed from subtelomeres toward telomeric repeat tracts, which have been implicated in telomere protection and heterochromatin formation. Genotoxic stress leads to upregulation of TERRAs. However, the mechanism of DNA damage-mediated TERRA induction remains elusive. Here, we treated HeLa cells with etoposide, a DNA double-strand break-generating agent, for various times and monitored the levels of TERRAs. Etoposide treatment led to a gradual time-dependent increase in TERRAs. Etoposide-mediated induction was evident in many TERRAs arising from various chromosome loci, including 20q and XpYp. Chromatin immunoprecipitation assays revealed no significant changes in the occupancy of RNA polymerase II at telomeres upon etoposide treatment. Interestingly, TERRAs arising from 20q, XpYp, 10q, and 13q degraded at slower rates in cells treated with etoposide, while degradation rates of TERRAs from many loci tested were nearly identical in both etoposide- and mock-treated cells. Telomere damage occurred from early time points of etoposide treatment, but telomere lengths and abundance of telomeric repeat-binding factor 2 (TRF2) at telomeres remained unchanged. In summary, etoposide treatment led to telomere damage and TERRA accumulation, but telomere lengths and TRF2-mediated telomere integrity were maintained. Etoposide-mediated TERRA accumulation could be attributed partly to RNA stabilization. These findings may provide insight into the post-transcriptional regulation of TERRAs in response to DNA damage.
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MESH Headings
- Antineoplastic Agents, Phytogenic/adverse effects
- Cell Survival/drug effects
- Chromosomes, Human, Pair 20/genetics
- Chromosomes, Human, X/genetics
- Chromosomes, Human, Y/genetics
- DNA Damage
- Etoposide/adverse effects
- Gene Expression Regulation, Neoplastic/drug effects
- HeLa Cells
- Humans
- RNA Stability
- RNA, Long Noncoding/chemistry
- RNA, Long Noncoding/genetics
- Telomere/drug effects
- Telomere/genetics
- Telomeric Repeat Binding Protein 2
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Affiliation(s)
- Bong-Kyeong Oh
- Institute for the Integration of Medicine and Innovative Technology, Hanyang University College of Medicine, Seoul, Korea
| | - Yoojung Choi
- Department of Translational Medicine, Hanyang University Graduate School of Biomedical Science and Engineering, Seoul, Korea
| | - Jaeman Bae
- Department of Obstetrics and Gynecology, Hanyang University College of Medicine, Seoul, Korea
| | - Won Moo Lee
- Department of Obstetrics and Gynecology, Hanyang University College of Medicine, Seoul, Korea
| | - Jeong-Kyu Hoh
- Department of Obstetrics and Gynecology, Hanyang University College of Medicine, Seoul, Korea
| | - Joong Sub Choi
- Institute for the Integration of Medicine and Innovative Technology, Hanyang University College of Medicine, Seoul, Korea
- Department of Obstetrics and Gynecology, Hanyang University College of Medicine, Seoul, Korea
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41
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Saha A, Nanavaty VP, Li B. Telomere and Subtelomere R-loops and Antigenic Variation in Trypanosomes. J Mol Biol 2019; 432:4167-4185. [PMID: 31682833 DOI: 10.1016/j.jmb.2019.10.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 10/02/2019] [Accepted: 10/21/2019] [Indexed: 12/12/2022]
Abstract
Trypanosoma brucei is a kinetoplastid parasite that causes African trypanosomiasis, which is fatal if left untreated. T. brucei regularly switches its major surface antigen, VSG, to evade the host immune responses. VSGs are exclusively expressed from subtelomeric expression sites (ESs) where VSG genes are flanked by upstream 70 bp repeats and downstream telomeric repeats. The telomere downstream of the active VSG is transcribed into a long-noncoding RNA (TERRA), which forms RNA:DNA hybrids (R-loops) with the telomeric DNA. At an elevated level, telomere R-loops cause more telomeric and subtelomeric double-strand breaks (DSBs) and increase VSG switching rate. In addition, stabilized R-loops are observed at the 70 bp repeats and immediately downstream of ES-linked VSGs in RNase H defective cells, which also have an increased amount of subtelomeric DSBs and more frequent VSG switching. Although subtelomere plasticity is expected to be beneficial to antigenic variation, severe defects in subtelomere integrity and stability increase cell lethality. Therefore, regulation of the telomere and 70 bp repeat R-loop levels is important for the balance between antigenic variation and cell fitness in T. brucei. In addition, the high level of the active ES transcription favors accumulation of R-loops at the telomere and 70 bp repeats, providing an intrinsic mechanism for local DSB formation, which is a strong inducer of VSG switching.
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Affiliation(s)
- Arpita Saha
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Science and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Vishal P Nanavaty
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Science and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA
| | - Bibo Li
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Science and Health Professions, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA; Case Comprehensive Cancer Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
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42
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Feretzaki M, Renck Nunes P, Lingner J. Expression and differential regulation of human TERRA at several chromosome ends. RNA (NEW YORK, N.Y.) 2019; 25:1470-1480. [PMID: 31350341 PMCID: PMC6795134 DOI: 10.1261/rna.072322.119] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 07/25/2019] [Indexed: 05/07/2023]
Abstract
The telomeric long noncoding RNA TERRA has been implicated in regulating telomere maintenance by telomerase and homologous recombination, and in influencing telomeric protein composition during the cell cycle and the telomeric DNA damage response. TERRA transcription starts at subtelomeric regions resembling the CpG islands of eukaryotic genes extending toward chromosome ends. TERRA contains chromosome-specific subtelomeric sequences at its 5' end and long tracts of UUAGGG-repeats toward the 3' end. Conflicting studies have been published as to whether TERRA is expressed from one or several chromosome ends. Here, we quantify TERRA species by RT-qPCR in normal and several cancerous human cell lines. By using chromosome-specific subtelomeric DNA primers, we demonstrate that TERRA is expressed from a large number of telomeres. Deficiency in DNA methyltransferases leads to TERRA up-regulation only at the subset of chromosome ends that contain CpG-island sequences, revealing differential regulation of TERRA promoters by DNA methylation. However, independently of the differences in TERRA expression, short telomeres were uniformly present in a DNA methyltransferase deficient cell line, indicating that telomere length was not dictated by TERRA expression in cis Bioinformatic analyses indicated the presence of a large number of putative transcription factors binding sites at TERRA promoters, and we identified a subset of them that repress TERRA expression. Altogether, our study confirms that TERRA corresponds to a large gene family transcribed from multiple chromosome ends where we identified two types of TERRA promoters, only one of which is regulated by DNA methylation.
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Affiliation(s)
- Marianna Feretzaki
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Patricia Renck Nunes
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Joachim Lingner
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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43
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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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44
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Liu B, Maekawa T, Yoshida K, Ly NH, Inoue K, Hasegawa A, Chatton B, Ogura A, Ishii S. Telomere shortening by transgenerational transmission of TNF-α-induced TERRA via ATF7. Nucleic Acids Res 2019; 47:283-298. [PMID: 30407559 PMCID: PMC6326783 DOI: 10.1093/nar/gky1149] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/30/2018] [Indexed: 12/30/2022] Open
Abstract
Various stresses increase disease susceptibility and accelerate aging, and increasing evidence suggests that these effects can be transmitted over generation. Epidemiological studies suggest that stressors experienced by parents affect the longevity of their offspring, possibly by regulating telomere dynamics. Telomeres are elongated by telomerase and shortened by certain stresses as well as telomere repeat-containing RNA (TERRA), a telomere transcript. However, the mechanism underlying the transgenerational effects is poorly understood. Here, we show that TNF-α, which is induced by various psychological stresses, induces the p38-dependent phosphorylation of ATF7, a stress-responsive chromatin regulator, in mouse testicular germ cells. This caused a release of ATF7 from the TERRA gene promoter in the subtelomeric region, which disrupted heterochromatin and induced TERRA. TERRA was transgenerationally transmitted to zygotes via sperm and caused telomere shortening. These results suggest that ATF7 and TERRA play key roles in paternal stress-induced telomere shortening in the offspring.
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Affiliation(s)
- Binbin Liu
- RIKEN Cluster for Pioneering Research, Tsukuba, Ibaraki 305-0074, Japan
| | - Toshio Maekawa
- RIKEN Cluster for Pioneering Research, Tsukuba, Ibaraki 305-0074, Japan
| | - Keisuke Yoshida
- RIKEN Cluster for Pioneering Research, Tsukuba, Ibaraki 305-0074, Japan
| | - Nhung Hong Ly
- RIKEN Cluster for Pioneering Research, Tsukuba, Ibaraki 305-0074, Japan.,Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Kimiko Inoue
- RIKEN BioResource Center, Tsukuba, Ibaraki 305-0074, Japan
| | - Ayumi Hasegawa
- RIKEN BioResource Center, Tsukuba, Ibaraki 305-0074, Japan
| | - Bruno Chatton
- Université de Strasbourg, UMR7242 Biotechnologie et Signalisation Cellulaire, Ecole Supérieure de Biotechnologie de Strasbourg, BP10413, Illkirch, France
| | - Atsuo Ogura
- RIKEN BioResource Center, Tsukuba, Ibaraki 305-0074, Japan
| | - Shunsuke Ishii
- RIKEN Cluster for Pioneering Research, Tsukuba, Ibaraki 305-0074, Japan.,Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
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45
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Marión RM, Montero JJ, López de Silanes I, Graña-Castro O, Martínez P, Schoeftner S, Palacios-Fábrega JA, Blasco MA. TERRA regulate the transcriptional landscape of pluripotent cells through TRF1-dependent recruitment of PRC2. eLife 2019; 8:44656. [PMID: 31426913 PMCID: PMC6701927 DOI: 10.7554/elife.44656] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 07/26/2019] [Indexed: 12/12/2022] Open
Abstract
The mechanisms that regulate pluripotency are still largely unknown. Here, we show that Telomere Repeat Binding Factor 1 (TRF1), a component of the shelterin complex, regulates the genome-wide binding of polycomb and polycomb H3K27me3 repressive marks to pluripotency genes, thereby exerting vast epigenetic changes that contribute to the maintenance of mouse ES cells in a naïve state. We further show that TRF1 mediates these effects by regulating TERRA, the lncRNAs transcribed from telomeres. We find that TERRAs are enriched at polycomb and stem cell genes in pluripotent cells and that TRF1 abrogation results in increased TERRA levels and in higher TERRA binding to those genes, coincidental with the induction of cell-fate programs and the loss of the naïve state. These results are consistent with a model in which TRF1-dependent changes in TERRA levels modulate polycomb recruitment to pluripotency and differentiation genes. These unprecedented findings explain why TRF1 is essential for the induction and maintenance of pluripotency.
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Affiliation(s)
- Rosa María Marión
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Juan J Montero
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Isabel López de Silanes
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Osvaldo Graña-Castro
- Bioinformatics Unit, Structural Biology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Paula Martínez
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Stefan Schoeftner
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | | | - Maria A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
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46
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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: 22] [Impact Index Per Article: 4.4] [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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47
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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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48
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The Emerging Roles of TERRA in Telomere Maintenance and Genome Stability. Cells 2019; 8:cells8030246. [PMID: 30875900 PMCID: PMC6468625 DOI: 10.3390/cells8030246] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/08/2019] [Accepted: 03/12/2019] [Indexed: 12/20/2022] Open
Abstract
The finding that transcription occurs at chromosome ends has opened new fields of study on the roles of telomeric transcripts in chromosome end maintenance and genome stability. Indeed, the ends of chromosomes are required to be protected from activation of DNA damage response and DNA repair pathways. Chromosome end protection is achieved by the activity of specific proteins that associate with chromosome ends, forming telomeres. Telomeres need to be constantly maintained as they are in a heterochromatic state and fold into specific structures (T-loops), which may hamper DNA replication. In addition, in the absence of maintenance mechanisms, chromosome ends shorten at every cell division due to limitations in the DNA replication machinery, which is unable to fully replicate the extremities of chromosomes. Altered telomere structure or critically short chromosome ends generate dysfunctional telomeres, ultimately leading to replicative senescence or chromosome instability. Telomere biology is thus implicated in multiple human diseases, including cancer. Emerging evidence indicates that a class of long noncoding RNAs transcribed at telomeres, known as TERRA for “TElomeric Repeat-containing RNA,” actively participates in the mechanisms regulating telomere maintenance and chromosome end protection. However, the molecular details of TERRA activities remain to be elucidated. In this review, we discuss recent findings on the emerging roles of TERRA in telomere maintenance and genome stability and their implications in human diseases.
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49
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Xu Y. Recent progress in human telomere RNA structure and function. Bioorg Med Chem Lett 2018; 28:2577-2584. [DOI: 10.1016/j.bmcl.2018.06.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 05/15/2018] [Accepted: 06/12/2018] [Indexed: 11/16/2022]
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50
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Gutiérrez I, Garavís M, de Lorenzo S, Villasante A, González C, Arias-Gonzalez JR. Single-Stranded Condensation Stochastically Blocks G-Quadruplex Assembly in Human Telomeric RNA. J Phys Chem Lett 2018; 9:2498-2503. [PMID: 29688724 DOI: 10.1021/acs.jpclett.8b00722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
TERRA is an RNA molecule transcribed from human subtelomeric regions toward chromosome ends potentially involved in regulation of heterochromatin stability, semiconservative replication, and telomerase inhibition, among others. TERRA contains tandem repeats of the sequence GGGUUA, with a strong tendency to fold into a four-stranded arrangement known as a parallel G-quadruplex. Here, we demonstrate by using single-molecule force spectroscopy that this potential is limited by the inherent capacity of RNA to self-associate randomly and further condense into entropically more favorable structures. We stretched RNA constructions with more than four and less than eight hexanucleotide repeats, thus unable to form several G-quadruplexes in tandem, flanked by non-G-rich overhangs of random sequence by optical tweezers on a one by one basis. We found that condensed RNA stochastically blocks G-quadruplex folding pathways with a near 20% probability, a behavior that is not found in DNA analogous molecules.
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Affiliation(s)
- Irene Gutiérrez
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia) , Cantoblanco, 28049 Madrid , Spain
| | - Miguel Garavís
- Instituto de Química Física Rocasolano, CSIC , C/Serrano 119 , 28006 Madrid , Spain
| | - Sara de Lorenzo
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia) , Cantoblanco, 28049 Madrid , Spain
| | - Alfredo Villasante
- Centro de Biología Molecular "Severo Ochoa" CSIC-UAM , C/Nicolás Cabrera 1 , 28049 Madrid , Spain
| | - Carlos González
- Instituto de Química Física Rocasolano, CSIC , C/Serrano 119 , 28006 Madrid , Spain
| | - J Ricardo Arias-Gonzalez
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia) , Cantoblanco, 28049 Madrid , Spain
- CNB-CSIC-IMDEA Nanociencia Associated Unit "Unidad de Nanobiotecnología" , Cantoblanco, 28049 Madrid , Spain
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