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Rivosecchi J, Jurikova K, Cusanelli E. Telomere-specific regulation of TERRA and its impact on telomere stability. Semin Cell Dev Biol 2024; 157:3-23. [PMID: 38088000 DOI: 10.1016/j.semcdb.2023.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/02/2023] [Indexed: 01/08/2024]
Abstract
TERRA is a class of telomeric repeat-containing RNAs that are expressed from telomeres in multiple organisms. TERRA transcripts play key roles in telomere maintenance and their physiological levels are essential to maintain the integrity of telomeric DNA. Indeed, deregulated TERRA expression or its altered localization can impact telomere stability by multiple mechanisms including fueling transcription-replication conflicts, promoting resection of chromosome ends, altering the telomeric chromatin, and supporting homologous recombination. Therefore, a fine-tuned control of TERRA is important to maintain the integrity of the genome. Several studies have reported that different cell lines express substantially different levels of TERRA. Most importantly, TERRA levels markedly vary among telomeres of a given cell type, indicating the existence of telomere-specific regulatory mechanisms which may help coordinate TERRA functions. TERRA molecules contain distinct subtelomeric sequences, depending on their telomere of origin, which may instruct specific post-transcriptional modifications or mediate distinct functions. In addition, all TERRA transcripts share a repetitive G-rich sequence at their 3' end which can form DNA:RNA hybrids and fold into G-quadruplex structures. Both structures are involved in TERRA functions and can critically affect telomere stability. In this review, we examine the mechanisms controlling TERRA levels and the impact of their telomere-specific regulation on telomere stability. We compare evidence obtained in different model organisms, discussing recent advances as well as controversies in the field. Furthermore, we discuss the importance of DNA:RNA hybrids and G-quadruplex structures in the context of TERRA biology and telomere maintenance.
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Affiliation(s)
- Julieta Rivosecchi
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy
| | - Katarina Jurikova
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy; Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská dolina, 84215 Bratislava, Slovakia
| | - Emilio Cusanelli
- Laboratory of Cell Biology and Molecular Genetics, Department CIBIO, University of Trento, via Sommarive 9, 38123 Trento, Italy.
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2
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Yegorov YE. Olovnikov, Telomeres, and Telomerase. Is It Possible to Prolong a Healthy Life? BIOCHEMISTRY. BIOKHIMIIA 2023; 88:1704-1718. [PMID: 38105192 DOI: 10.1134/s0006297923110032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/29/2023] [Accepted: 08/31/2023] [Indexed: 12/19/2023]
Abstract
The science of telomeres and telomerase has made tremendous progress in recent decades. In this review, we consider it first in a historical context (the Carrel-Hayflick-Olovnikov-Blackburn chain of discoveries) and then review current knowledge on the telomere structure and dynamics in norm and pathology. Central to the review are consequences of the telomere shortening, including telomere position effects, DNA damage signaling, and increased genetic instability. Cell senescence and role of telomere length in its development are discussed separately. Therapeutic aspects and risks of telomere lengthening methods including use of telomerase and other approaches are also discussed.
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Affiliation(s)
- Yegor E Yegorov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia.
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3
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Sutterlüty H, Bargl M, Holzmann K. Quantifying telomere transcripts as tool to improve risk assessment for genetic instability and genotoxicity. MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2023; 891:503690. [PMID: 37770147 DOI: 10.1016/j.mrgentox.2023.503690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 08/18/2023] [Accepted: 09/04/2023] [Indexed: 10/03/2023]
Abstract
Telomere repeat-containing RNAs (TERRA) are transcribed from telomeres as long non-coding RNAs and are part of the telomere structure with protective function. The genetic stability of cells requires telomeric repeats at the ends of chromosomes. Maintenance of telomere length (TL) is essential for proliferative capacity and chromosomal integrity. In contrast, telomere shortening is a recognized risk factor for carcinogenesis and a biomarker of aging due to the cumulative effects of environmental exposures and life experiences such as trauma or stress. In this context, telomere repeats are lost due to cell proliferation, but are also susceptible to stress factors including reactive oxygen species (ROS) inducing oxidative base damage. Quantitative PCR (qPCR) of genomic DNA is an established method to analyze TL as a tool to detect genotoxic events. That same qPCR method can be applied to RNA converted into cDNA to quantify TERRA as a useful tool to perform high-throughput screenings. This short review summarizes relevant qPCR studies using both TL and TERRA quantification, provides an overall view of the molecular mechanisms of telomere protection against ROS by TERRA, and summarizes the presented studies comparing the results at DNA and RNA levels, which indicate that fluctuations at transcript level might reflect a short-term response. Therefore, we conclude that performing both of these measurements together will improve genotoxicity studies.
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Affiliation(s)
- Hedwig Sutterlüty
- Center for Cancer Research, Comprehensive Cancer Center, Medical University Vienna, Borschkegasse 8a, A-1090 Vienna, Austria
| | - Maximilian Bargl
- Center for Cancer Research, Comprehensive Cancer Center, Medical University Vienna, Borschkegasse 8a, A-1090 Vienna, Austria
| | - Klaus Holzmann
- Center for Cancer Research, Comprehensive Cancer Center, Medical University Vienna, Borschkegasse 8a, A-1090 Vienna, Austria.
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4
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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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5
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Friesen CR, Wapstra E, Olsson M. Of telomeres and temperature: Measuring thermal effects on telomeres in ectothermic animals. Mol Ecol 2022; 31:6069-6086. [PMID: 34448287 DOI: 10.1111/mec.16154] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/20/2021] [Accepted: 08/23/2021] [Indexed: 01/31/2023]
Abstract
Ectotherms are classic models for understanding life-history tradeoffs, including the reproduction-somatic maintenance tradeoffs that may be reflected in telomere length and their dynamics. Importantly, life-history traits of ectotherms are tightly linked to their thermal environment, with diverse or synergistic mechanistic explanations underpinning the variation. Telomere dynamics potentially provide a mechanistic link that can be used to monitor thermal effects on individuals in response to climatic perturbations. Growth rate, age and developmental stage are all affected by temperature, which interacts with telomere dynamics in complex and intriguing ways. The physiological processes underpinning telomere dynamics can be visualized and understood using thermal performance curves (TPCs). TPCs reflect the evolutionary history and the thermal environment during an individual's ontogeny. Telomere maintenance should be enhanced at or near the thermal performance optimum of a species, population and individual. The thermal sensitivity of telomere dynamics should reflect the interacting TPCs of the processes underlying them. The key processes directly underpinning telomere dynamics are mitochondrial function (reactive oxygen production), antioxidant activity, telomerase activity and telomere endcap protein status. We argue that identifying TPCs for these processes will significantly help design robust, repeatable experiments and field studies of telomere dynamics in ectotherms. Conceptually, TPCs are a valuable framework to predict and interpret taxon- and population-specific telomere dynamics across thermal regimes. The literature of thermal effects on telomeres in ectotherms is sparse and mostly limited to vertebrates, but our conclusions and recommendations are relevant across ectothermic animals.
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Affiliation(s)
- Christopher R Friesen
- School of Earth, Atmospheric and Life Sciences, The University of Wollongong, Wollongong, New South Wales, Australia.,School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales, Australia
| | - Erik Wapstra
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - Mats Olsson
- School of Earth, Atmospheric and Life Sciences, The University of Wollongong, Wollongong, New South Wales, Australia.,Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
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6
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Kroupa M, Tomasova K, Kavec M, Skrobanek P, Buchler T, Kumar R, Vodickova L, Vodicka P. TElomeric repeat-containing RNA (TERRA): Physiological functions and relevance in cancer. Front Oncol 2022; 12:913314. [PMID: 35982970 PMCID: PMC9380590 DOI: 10.3389/fonc.2022.913314] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 07/12/2022] [Indexed: 11/13/2022] Open
Abstract
Telomeres are complex protective structures located at the ends of linear eukaryotic chromosomes. Their purpose is to prevent genomic instability. Research progress in telomere biology during the past decades has identified a network of telomeric transcripts of which the best-studied is TElomeric Repeat-containing RNA (TERRA). TERRA was shown to be important not only for the preservation of telomere homeostasis and genomic stability but also for the expression of hundreds of genes across the human genome. These findings added a new level of complexity to telomere biology. Herein we provide insights on the telomere transcriptome, its relevance for proper telomere function, and its implications in human pathology. We also discuss possible clinical opportunities of exosomal telomere transcripts detection as a biomarker in cancer precision medicine.
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Affiliation(s)
- Michal Kroupa
- Department of the Molecular Biology of Cancer, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia
- Faculty of Medicine and Biomedical Center in Pilsen, Charles University, Pilsen, Czechia
- *Correspondence: Michal Kroupa, ; Pavel Vodicka,
| | - Kristyna Tomasova
- Department of the Molecular Biology of Cancer, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia
- Faculty of Medicine and Biomedical Center in Pilsen, Charles University, Pilsen, Czechia
| | - Miriam Kavec
- Department of the Molecular Biology of Cancer, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia
- Department of Oncology, First Faculty of Medicine, Charles University and Thomayer University Hospital, Prague, Czechia
| | - Pavel Skrobanek
- Department of Oncology, First Faculty of Medicine, Charles University and Thomayer University Hospital, Prague, Czechia
| | - Tomas Buchler
- Department of Oncology, First Faculty of Medicine, Charles University and Thomayer University Hospital, Prague, Czechia
| | - Rajiv Kumar
- Department of the Molecular Biology of Cancer, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia
- Division of Molecular Genetic Epidemiology, German Cancer Research Center, Heidelberg, Germany
| | - Ludmila Vodickova
- Department of the Molecular Biology of Cancer, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia
- Faculty of Medicine and Biomedical Center in Pilsen, Charles University, Pilsen, Czechia
- Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University, Prague, Czechia
| | - Pavel Vodicka
- Department of the Molecular Biology of Cancer, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czechia
- Faculty of Medicine and Biomedical Center in Pilsen, Charles University, Pilsen, Czechia
- Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University, Prague, Czechia
- *Correspondence: Michal Kroupa, ; Pavel Vodicka,
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7
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Vourc’h C, Dufour S, Timcheva K, Seigneurin-Berny D, Verdel A. HSF1-Activated Non-Coding Stress Response: Satellite lncRNAs and Beyond, an Emerging Story with a Complex Scenario. Genes (Basel) 2022; 13:genes13040597. [PMID: 35456403 PMCID: PMC9032817 DOI: 10.3390/genes13040597] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/18/2022] [Accepted: 03/19/2022] [Indexed: 12/21/2022] Open
Abstract
In eukaryotes, the heat shock response is orchestrated by a transcription factor named Heat Shock Factor 1 (HSF1). HSF1 is mostly characterized for its role in activating the expression of a repertoire of protein-coding genes, including the heat shock protein (HSP) genes. Remarkably, a growing set of reports indicate that, upon heat shock, HSF1 also targets various non-coding regions of the genome. Focusing primarily on mammals, this review aims at reporting the identity of the non-coding genomic sites directly bound by HSF1, and at describing the molecular function of the long non-coding RNAs (lncRNAs) produced in response to HSF1 binding. The described non-coding genomic targets of HSF1 are pericentric Satellite DNA repeats, (sub)telomeric DNA repeats, Short Interspersed Nuclear Element (SINE) repeats, transcriptionally active enhancers and the NEAT1 gene. This diverse set of non-coding genomic sites, which already appears to be an integral part of the cellular response to stress, may only represent the first of many. Thus, the study of the evolutionary conserved heat stress response has the potential to emerge as a powerful cellular context to study lncRNAs, produced from repeated or unique DNA regions, with a regulatory function that is often well-documented but a mode of action that remains largely unknown.
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Affiliation(s)
- Claire Vourc’h
- Université de Grenoble Alpes (UGA), 38700 La Tronche, France
- Correspondence: (C.V.); (A.V.)
| | - Solenne Dufour
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
| | - Kalina Timcheva
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
| | - Daphné Seigneurin-Berny
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
| | - André Verdel
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U 1209/CNRS UMR 5309, Site Santé-Allée des Alpes, 38700 La Tronche, France; (S.D.); (K.T.); (D.S.-B.)
- Correspondence: (C.V.); (A.V.)
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8
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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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9
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Alecki C, Vera M. Role of Nuclear Non-Canonical Nucleic Acid Structures in Organismal Development and Adaptation to Stress Conditions. Front Genet 2022; 13:823241. [PMID: 35281835 PMCID: PMC8906566 DOI: 10.3389/fgene.2022.823241] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 01/25/2022] [Indexed: 11/21/2022] Open
Abstract
Over the last decades, numerous examples have involved nuclear non-coding RNAs (ncRNAs) in the regulation of gene expression. ncRNAs can interact with the genome by forming non-canonical nucleic acid structures such as R-loops or DNA:RNA triplexes. They bind chromatin and DNA modifiers and transcription factors and favor or prevent their targeting to specific DNA sequences and regulate gene expression of diverse genes. We review the function of these non-canonical nucleic acid structures in regulating gene expression of multicellular organisms during development and in response to different stress conditions and DNA damage using examples described in several organisms, from plants to humans. We also overview recent techniques developed to study where R-loops or DNA:RNA triplexes are formed in the genome and their interaction with proteins.
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Affiliation(s)
- Célia Alecki
- Department of Biochemistry, McGill University, Montreal, QC, Canada
| | - Maria Vera
- Department of Biochemistry, McGill University, Montreal, QC, Canada
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10
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Badmus KA, Idrus Z, Meng GY, Sazili AQ, Mamat-Hamidi K. Telomere Length and Regulatory Genes as Novel Stress Biomarkers and Their Diversities in Broiler Chickens ( Gallus gallus domesticus) Subjected to Corticosterone Feeding. Animals (Basel) 2021; 11:ani11102759. [PMID: 34679783 PMCID: PMC8532957 DOI: 10.3390/ani11102759] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/16/2021] [Accepted: 08/23/2021] [Indexed: 12/15/2022] Open
Abstract
Simple Summary Assessment of poultry welfare is very crucial for sustainable production in the tropics. There is a demand for alternatives to plasma corticosterone levels as they have received much criticism as an unsuitable predictor of animal welfare due to inconsistency. In this study, we noticed no effect of age on plasma corticosterone (CORT) although it was altered by CORT treatment. However, growth performances and organ weight were affected by CORT treatment and age. The broad sense evaluation of telomere length in this study revealed that telomere length in the blood, muscle, liver and heart was shortened by chronic stress induced by corticosterone administration. The expression profile of the telomere regulatory genes was altered by chronic stress. This study informed us of the potential of telomere length and its regulatory genes in the assessment of animal welfare in the poultry sector for sustainable production. Abstract This study was designed to characterize telomere length and its regulatory genes and to evaluate their potential as well-being biomarkers. Chickens were fed a diet containing corticosterone (CORT) for 4 weeks and performances, organ weight, plasma CORT levels, telomere lengths and regulatory genes were measured and recorded. Body weights of CORT-fed chickens were significantly suppressed (p < 0.05), and organ weights and circulating CORT plasma levels (p < 0.05) were altered. Interaction effect of CORT and duration was significant (p < 0.05) on heart and liver telomere length. CORT significantly (p < 0.05) shortened the telomere length of the whole blood, muscle, liver and heart. The TRF1, chTERT, TELO2 and HSF1 were significantly (p < 0.05) upregulated in the liver and heart at week 4 although these genes and TERRA were downregulated in the muscles at weeks 2 and 4. Therefore, telomere lengths and their regulators are associated and diverse, so they can be used as novel biomarkers of stress in broiler chickens fed with CORT.
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Affiliation(s)
- Kazeem Ajasa Badmus
- Department of Animal Science, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia; (K.A.B.); (Z.I.); (A.Q.S.)
- Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia;
| | - Zulkifli Idrus
- Department of Animal Science, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia; (K.A.B.); (Z.I.); (A.Q.S.)
- Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia;
| | - Goh Yong Meng
- Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia;
- Department of Veterinary Pre-Clinical Science, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia
| | - Awis Qurni Sazili
- Department of Animal Science, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia; (K.A.B.); (Z.I.); (A.Q.S.)
- Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia;
| | - Kamalludin Mamat-Hamidi
- Department of Animal Science, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia; (K.A.B.); (Z.I.); (A.Q.S.)
- Institute of Tropical Agriculture and Food Security, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia;
- Correspondence:
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11
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TERRA transcription destabilizes telomere integrity to initiate break-induced replication in human ALT cells. Nat Commun 2021; 12:3760. [PMID: 34145295 PMCID: PMC8213692 DOI: 10.1038/s41467-021-24097-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 05/31/2021] [Indexed: 01/22/2023] Open
Abstract
Alternative Lengthening of Telomeres (ALT) is a Break-Induced Replication (BIR)-based mechanism elongating telomeres in a subset of human cancer cells. While the notion that spontaneous DNA damage at telomeres is required to initiate ALT, the molecular triggers of this physiological telomere instability are largely unknown. We previously proposed that the telomeric long noncoding RNA TERRA may represent one such trigger; however, given the lack of tools to suppress TERRA transcription in cells, our hypothesis remained speculative. We have developed Transcription Activator-Like Effectors able to rapidly inhibit TERRA transcription from multiple chromosome ends in an ALT cell line. TERRA transcription inhibition decreases marks of DNA replication stress and DNA damage at telomeres and impairs ALT activity and telomere length maintenance. We conclude that TERRA transcription actively destabilizes telomere integrity in ALT cells, thereby triggering BIR and promoting telomere elongation. Our data point to TERRA transcription manipulation as a potentially useful target for therapy. TERRA RNA has previously been linked to Alternative lengthening of telomeres (ALT). Here the authors developed a tool to rapidly inhibit TERRA transcription from different chromosome ends in an ALT cell line to show that TERRA transcription actively promotes break induced replication (BIR) and destabilizes telomere integrity in ALT cells.
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12
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Dong X, Sun S, Zhang L, Kim S, Tu Z, Montagna C, Maslov AY, Suh Y, Wang T, Campisi J, Vijg J. Age-related telomere attrition causes aberrant gene expression in sub-telomeric regions. Aging Cell 2021; 20:e13357. [PMID: 34018656 PMCID: PMC8208793 DOI: 10.1111/acel.13357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 03/01/2021] [Accepted: 03/07/2021] [Indexed: 12/13/2022] Open
Abstract
Telomere attrition has been proposed as a biomarker and causal factor in aging. In addition to causing cellular senescence and apoptosis, telomere shortening has been found to affect gene expression in subtelomeric regions. Here, we analyzed the distribution of age-related differentially expressed genes from the GTEx RNA sequencing database of 54 tissue types from 979 human subjects and found significantly more upregulated than downregulated genes in subtelomeric regions as compared to the genome-wide average. Our data demonstrate spatial relationships between telomeres and gene expression in aging.
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Affiliation(s)
- Xiao Dong
- Department of GeneticsAlbert Einstein College of MedicineBronxNYUSA
- Institute on the Biology of Aging and MetabolismDepartment of Genetics, Cell Biology and DevelopmentUniversity of MinnesotaMinneapolisMNUSA
| | - Shixiang Sun
- Department of GeneticsAlbert Einstein College of MedicineBronxNYUSA
| | - Lei Zhang
- Department of GeneticsAlbert Einstein College of MedicineBronxNYUSA
- Institute on the Biology of Aging and MetabolismDepartment of Genetics, Cell Biology and DevelopmentUniversity of MinnesotaMinneapolisMNUSA
| | - Seungsoo Kim
- Department of Obstetrics and GynecologyColumbia University Irving Medical CenterNew YorkNYUSA
| | - Zhidong Tu
- Department of Genetics and Genomic SciencesIcahn Institute for Genomics and Multiscale BiologyIcahn School of Medicine Mount SinaiNew YorkNYUSA
| | | | - Alexander Y. Maslov
- Department of GeneticsAlbert Einstein College of MedicineBronxNYUSA
- Laboratory of Applied Genomic TechnologiesVoronezh State University of Engineering TechnologyVoronezhRussia
| | - Yousin Suh
- Department of Obstetrics and GynecologyColumbia University Irving Medical CenterNew YorkNYUSA
- Department of Genetics and DevelopmentColumbia University Irving Medical CenterNew YorkNYUSA
| | - Tao Wang
- Department of Epidemiology & Population HealthAlbert Einstein College of MedicineBronxNYUSA
| | | | - Jan Vijg
- Department of GeneticsAlbert Einstein College of MedicineBronxNYUSA
- School of Public HealthCenter for Single‐Cell OmicsShanghai Jiao Tong University School of MedicineShanghaiChina
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13
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The Power of Stress: The Telo-Hormesis Hypothesis. Cells 2021; 10:cells10051156. [PMID: 34064566 PMCID: PMC8151059 DOI: 10.3390/cells10051156] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/29/2021] [Accepted: 05/06/2021] [Indexed: 02/06/2023] Open
Abstract
Adaptative response to stress is a strategy conserved across evolution to promote survival. In this context, the groundbreaking findings of Miroslav Radman on the adaptative value of changing mutation rates opened new avenues in our understanding of stress response. Inspired by this work, we explore here the putative beneficial effects of changing the ends of eukaryotic chromosomes, the telomeres, in response to stress. We first summarize basic principles in telomere biology and then describe how various types of stress can alter telomere structure and functions. Finally, we discuss the hypothesis of stress-induced telomere signaling with hormetic effects.
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14
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Gala K, Khattar E. Long non-coding RNAs at work on telomeres: Functions and implications in cancer therapy. Cancer Lett 2021; 502:120-132. [PMID: 33450357 DOI: 10.1016/j.canlet.2020.12.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 12/13/2020] [Accepted: 12/29/2020] [Indexed: 12/27/2022]
Abstract
Long non-coding RNAs (lncRNAs) are known to regulate various biological processes including cancer. Cancer cells possess limitless replicative potential which is attained by telomere length maintenance while normal somatic cells have a limited lifespan because their telomeres shorten with every cell division ultimately triggering replicative senescence. Two lncRNAs have been observed to play a key role in telomere length maintenance. First is the lncRNA TERC (telomerase RNA component) which functions as a template for telomeric DNA synthesis in association with telomerase reverse transcriptase (TERT) which serves as the catalytic component. Together they constitute the telomerase complex which functions as a reverse transcriptase to elongate telomeres. Second lncRNA that helps in regulating telomere length is the telomeric repeat-containing RNA (TERRA) which is transcribed from the subtelomeric region and extends to the telomeric region. TERC and TERRA exhibit important functions in cancer with implications in precision oncology. In this review, we discuss various aspects of these important lncRNAs in humans and their role in cancer along with recent advancements in their anticancer therapeutic application.
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Affiliation(s)
- Kavita Gala
- Sunandan Divatia School of Science, SVKM's NMIMS (Deemed to be) University, Mumbai, 400056, Maharashtra, India
| | - Ekta Khattar
- Sunandan Divatia School of Science, SVKM's NMIMS (Deemed to be) University, Mumbai, 400056, Maharashtra, India.
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15
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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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16
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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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17
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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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18
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Martens DS, Plusquin M, Cox B, Nawrot TS. Early Biological Aging and Fetal Exposure to High and Low Ambient Temperature: A Birth Cohort Study. ENVIRONMENTAL HEALTH PERSPECTIVES 2019; 127:117001. [PMID: 31691586 PMCID: PMC6927502 DOI: 10.1289/ehp5153] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 08/26/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Although studies have provided estimates of premature mortality to either heat or cold in adult populations, and fetal exposure to ambient temperature may be associated with life expectancy, the effects of temperature on aging in early life have not yet been studied. Telomere length (TL) is a marker of biological aging, and a short TL at birth may predict lifespan and disease susceptibility later in life. OBJECTIVES We studied to what extent prenatal ambient temperature exposure is associated with newborn TL. METHODS In the ENVIRONAGE (ENVIRonmental influence ON early AGEing) birth cohort in Flanders, Belgium, we measured cord blood and placental TL in 1,103 mother-newborn pairs (singletons with ≥36wk of gestation) using a quantitative real-time polymerase chain reaction (qPCR) method. We associated newborn TL with average weekly exposure to ambient temperature using distributed lag nonlinear models (DLNMs) while controlling for potential confounders. Double-threshold DLNMs were used to estimate cold and heat thresholds and the linear associations between temperature and TL below the cold threshold and above the heat threshold. RESULTS Prenatal temperature exposure above the heat threshold (19.5°C) was associated with shorter cord blood TL. The association with a 1°C increase in temperature was strongest at week 36 of gestation and resulted in a 3.29% [95% confidence interval (CI): -4.67, -1.88] shorter cord blood TL. Consistently, prenatal temperature exposure below the cold threshold (5.0°C) was associated with longer cord blood TL. The association with a 1°C decrease in temperature was strongest at week 10 of gestation with 0.72% (95% CI: 0.46, 0.97) longer cord blood TL. DISCUSSION Our study supports potential effects of prenatal temperature exposure on longevity and disease susceptibility later in life. Future climate scenarios might jeopardize the potential molecular longevity of future generations from birth onward. https://doi.org/10.1289/EHP5153.
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Affiliation(s)
- Dries S Martens
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Michelle Plusquin
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Bianca Cox
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
| | - Tim S Nawrot
- Centre for Environmental Sciences, Hasselt University, Hasselt, Belgium
- Department of Public Health and Primary Care, Leuven University, Leuven, Belgium
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19
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Perera ON, Sobinoff AP, Teber ET, Harman A, Maritz MF, Yang SF, Pickett HA, Cesare AJ, Arthur JW, MacKenzie KL, Bryan TM. Telomerase promotes formation of a telomere protective complex in cancer cells. SCIENCE ADVANCES 2019; 5:eaav4409. [PMID: 31616780 PMCID: PMC6774720 DOI: 10.1126/sciadv.aav4409] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 09/09/2019] [Indexed: 05/04/2023]
Abstract
Telomerase is a ribonucleoprotein complex that catalyzes addition of telomeric DNA repeats to maintain telomeres in replicating cells. Here, we demonstrate that the telomerase protein hTERT performs an additional role at telomeres that is independent of telomerase catalytic activity yet essential for telomere integrity and cell proliferation. Short-term depletion of endogenous hTERT reduced the levels of heat shock protein 70 (Hsp70-1) and the telomere protective protein Apollo at telomeres, and induced telomere deprotection and cell cycle arrest, in the absence of telomere shortening. Short-term expression of hTERT promoted colocalization of Hsp70-1 with telomeres and Apollo and reduced numbers of deprotected telomeres, in a manner independent of telomerase catalytic activity. These data reveal a previously unidentified noncanonical function of hTERT that promotes formation of a telomere protective complex containing Hsp70-1 and Apollo and is essential for sustained proliferation of telomerase-positive cancer cells, likely contributing to the known cancer-promoting effects of both hTERT and Hsp70-1.
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Affiliation(s)
- Omesha N. Perera
- Cell Biology Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Alexander P. Sobinoff
- Telomere Length Regulation Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Erdahl T. Teber
- Bioinformatics Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Ashley Harman
- Cell Biology Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Michelle F. Maritz
- Children’s Cancer Institute, School of Women’s and Children’s Health, University of NSW, NSW 2052, Australia
| | - Sile F. Yang
- Telomere Length Regulation Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Hilda A. Pickett
- Telomere Length Regulation Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Anthony J. Cesare
- Genome Integrity Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Jonathan W. Arthur
- Bioinformatics Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Karen L. MacKenzie
- Children’s Cancer Institute, School of Women’s and Children’s Health, University of NSW, NSW 2052, Australia
| | - Tracy M. Bryan
- Cell Biology Unit, Children’s Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
- Corresponding author.
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20
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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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21
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Mensà E, Latini S, Ramini D, Storci G, Bonafè M, Olivieri F. The telomere world and aging: Analytical challenges and future perspectives. Ageing Res Rev 2019; 50:27-42. [PMID: 30615937 DOI: 10.1016/j.arr.2019.01.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/15/2018] [Accepted: 01/03/2019] [Indexed: 12/12/2022]
Abstract
Telomeres, the terminal nucleoprotein structures of eukaryotic chromosomes, play pleiotropic functions in cellular and organismal aging. Telomere length (TL) varies throughout life due to the influence of genetic factors and to a complex balancing between "shortening" and "elongation" signals. Telomerase, the only enzyme that can elongate a telomeric DNA chain, and telomeric repeat-containing RNA (TERRA), a long non-coding RNA involved in looping maintenance, play key roles in TL during life. Despite recent advances in the knowledge of TL, TERRA and telomerase activity (TA) biology and their measurement techniques, the experimental and theoretical issues involved raise a number of problems that should carefully be considered by researchers approaching the "telomere world". The increasing use of such parameters - hailed as promising clinically relevant biomarkers - has failed to be paralleled by the development of automated and standardized measurement technology. Consequently, associating given TL values to specific pathological conditions involves on the one hand technological issues and on the other clinical-biological issues related to the planning of clinically relevant association studies. Addressing these issues would help avoid major biases in association studies involving TL and a number of outcomes, especially those focusing on psychological and bio-behavioral variables. The main challenge in telomere research is the development of accurate and reliable measurement methods to achieve simple and sensitive TL, TERRA, and TA detection. The discovery of the localization of telomeres and TERRA in cellular and extracellular compartments had added an additional layer of complexity to the measurement of these age-related biomarkers. Since combined analysis of TL, TERRA and TA may well provide more exhaustive clinical information than a single parameter, we feel it is important for researchers in the various fields to become familiar with their most common measurement techniques and to be aware of the respective merits and drawbacks of these approaches.
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Affiliation(s)
- Emanuela Mensà
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy
| | - Silvia Latini
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy
| | - Deborah Ramini
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy
| | - Gianluca Storci
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy; Interdepartmental Centre "L. Galvani" (CIG), University of Bologna, Bologna, Italy
| | - Massimiliano Bonafè
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy; Interdepartmental Centre "L. Galvani" (CIG), University of Bologna, Bologna, Italy; Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), IRCCS, Biosciences Laboratory, Meldola, Italy
| | - Fabiola Olivieri
- Department of Clinical and Molecular Sciences, DISCLIMO, Università Politecnica delle Marche, Ancona, Italy; Center of Clinical Pathology and Innovative Therapy, IRCCS INRCA, Ancona, Italy.
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22
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Barna J, Csermely P, Vellai T. Roles of heat shock factor 1 beyond the heat shock response. Cell Mol Life Sci 2018; 75:2897-2916. [PMID: 29774376 PMCID: PMC11105406 DOI: 10.1007/s00018-018-2836-6] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/07/2018] [Indexed: 01/09/2023]
Abstract
Various stress factors leading to protein damage induce the activation of an evolutionarily conserved cell protective mechanism, the heat shock response (HSR), to maintain protein homeostasis in virtually all eukaryotic cells. Heat shock factor 1 (HSF1) plays a central role in the HSR. HSF1 was initially known as a transcription factor that upregulates genes encoding heat shock proteins (HSPs), also called molecular chaperones, which assist in refolding or degrading injured intracellular proteins. However, recent accumulating evidence indicates multiple additional functions for HSF1 beyond the activation of HSPs. Here, we present a nearly comprehensive list of non-HSP-related target genes of HSF1 identified so far. Through controlling these targets, HSF1 acts in diverse stress-induced cellular processes and molecular mechanisms, including the endoplasmic reticulum unfolded protein response and ubiquitin-proteasome system, multidrug resistance, autophagy, apoptosis, immune response, cell growth arrest, differentiation underlying developmental diapause, chromatin remodelling, cancer development, and ageing. Hence, HSF1 emerges as a major orchestrator of cellular stress response pathways.
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Affiliation(s)
- János Barna
- Department of Genetics, Eötvös Loránd University, Pázmány Péter Stny. 1/C, Budapest, 1117, Hungary
- MTA-ELTE Genetics Research Group, Eötvös Loránd University, Budapest, Hungary
| | - Péter Csermely
- Department of Medical Chemistry, Semmelweis University, Budapest, Hungary
| | - Tibor Vellai
- Department of Genetics, Eötvös Loránd University, Pázmány Péter Stny. 1/C, Budapest, 1117, Hungary.
- MTA-ELTE Genetics Research Group, Eötvös Loránd University, Budapest, Hungary.
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23
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Dai C. The heat-shock, or HSF1-mediated proteotoxic stress, response in cancer: from proteomic stability to oncogenesis. Philos Trans R Soc Lond B Biol Sci 2018; 373:rstb.2016.0525. [PMID: 29203710 DOI: 10.1098/rstb.2016.0525] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2017] [Indexed: 12/17/2022] Open
Abstract
The heat-shock, or HSF1-mediated proteotoxic stress, response (HSR/HPSR) is characterized by induction of heat-shock proteins (HSPs). As molecular chaperones, HSPs facilitate the folding, assembly, transportation and degradation of other proteins. In mammals, heat shock factor 1 (HSF1) is the master regulator of this ancient transcriptional programme. Upon proteotoxic insults, the HSR/HPSR is essential to proteome homeostasis, or proteostasis, thereby resisting stress and antagonizing protein misfolding diseases and ageing. Contrasting with these benefits, an unexpected pro-oncogenic role of the HSR/HPSR is unfolding. Whereas HSF1 remains latent in primary cells without stress, it becomes constitutively activated within malignant cells, rendering them addicted to HSF1 for their growth and survival. Highlighting the HSR/HPSR as an integral component of the oncogenic network, several key pathways governing HSF1 activation by environmental stressors are causally implicated in malignancy. Importantly, HSF1 impacts the cancer proteome systemically. By suppressing tumour-suppressive amyloidogenesis, HSF1 preserves cancer proteostasis to support the malignant state, both providing insight into how HSF1 enables tumorigenesis and suggesting disruption of cancer proteostasis as a therapeutic strategy. This review provides an overview of the role of HSF1 in oncogenesis, mechanisms underlying its constitutive activation within cancer cells and its pro-oncogenic action, as well as potential HSF1-targeting strategies.This article is part of the theme issue 'Heat shock proteins as modulators and therapeutic targets of chronic disease: an integrated perspective'.
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Affiliation(s)
- Chengkai Dai
- Mouse Cancer Genetics Program, Center for Cancer Research NCI-Frederick, Building 560, Room 32-31b, 1050 Boyles Street, Frederick, MD 21702, USA
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24
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Avogaro L, Querido E, Dalachi M, Jantsch MF, Chartrand P, Cusanelli E. Live-cell imaging reveals the dynamics and function of single-telomere TERRA molecules in cancer cells. RNA Biol 2018; 15:787-796. [PMID: 29658398 PMCID: PMC6152429 DOI: 10.1080/15476286.2018.1456300] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Telomeres cap the ends of eukaryotic chromosomes, protecting them from degradation and erroneous recombination events which may lead to genome instability. Telomeres are transcribed giving rise to telomeric repeat-containing RNAs, called TERRA. The TERRA long noncoding RNAs have been proposed to play important roles in telomere biology, including heterochromatin formation and telomere length homeostasis. While TERRA RNAs are predominantly nuclear and localize at telomeres, little is known about the dynamics and function of TERRA molecules expressed from individual telomeres. Herein, we developed an assay to image endogenous TERRA molecules expressed from a single telomere in living human cancer cells. We show that single-telomere TERRA can be detected as TERRA RNA single particles which freely diffuse within the nucleus. Furthermore, TERRA molecules aggregate forming TERRA clusters. Three-dimensional size distribution and single particle tracking analyses revealed distinct sizes and dynamics for TERRA RNA single particles and clusters. Simultaneous time lapse confocal imaging of TERRA particles and telomeres showed that TERRA clusters transiently co-localize with telomeres. Finally, we used chemically modified antisense oligonucleotides to deplete TERRA molecules expressed from a single telomere. Single-telomere TERRA depletion resulted in increased DNA damage at telomeres and elsewhere in the genome. These results suggest that single-telomere TERRA transcripts participate in the maintenance of genomic integrity in human cancer cells.
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Affiliation(s)
- Laura Avogaro
- a Centre for Integrative Biology (CIBIO), University of Trento , Trento , Italy
| | - Emmanuelle Querido
- b Department of Biochemistry and Molecular Medicine , Université de Montréal , QC , Canada
| | - Myriam Dalachi
- b Department of Biochemistry and Molecular Medicine , Université de Montréal , QC , Canada
| | - Michael F Jantsch
- c Centre of Anatomy and Cell Biology, Medical University of Vienna , Vienna , Austria
| | - Pascal Chartrand
- b Department of Biochemistry and Molecular Medicine , Université de Montréal , QC , Canada
| | - Emilio Cusanelli
- a Centre for Integrative Biology (CIBIO), University of Trento , Trento , Italy
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