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Yang C, Gong Y, Liu S, Sun C, Wang T, Chen X, Liu W, Zhang X, Yang Y, Zhang M. LincR-PPP2R5C deficiency enhancing the fungicidal activity of neutrophils in pulmonary cryptococcosis is linked to the upregulation of IL-4. mBio 2024:e0213024. [PMID: 39287443 DOI: 10.1128/mbio.02130-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2024] [Accepted: 08/26/2024] [Indexed: 09/19/2024] Open
Abstract
Pulmonary cryptococcosis is a common complication in immunocompromised patients. In a mouse model of pulmonary cryptococcosis, Cryptococcus neoformans induces a type 2 immune response that is detrimental to host protection. Long non-coding RNAs (lncRNAs) have emerged as key players in the pathogenesis of infectious diseases. However, the roles and mechanisms of lncRNAs in fungal infection are largely elusive. In the present study, we aimed to explore the roles of LincR-PPP2R5C in pulmonary cryptococcosis. We observed an increase in the level of LincR-PPP2R5C in the lung tissues of C57BL/6J mice after tracheal infection with C. neoformans. Subsequently, we intratracheally infected LincR-PPP2R5C knockout (KO) mice and wild-type mice with C. neoformans. LincR-PPP2R5C deficiency mitigates C. neoformans infection, which can be demonstrated by extending survival time and decreasing fungal burden in the lung. In the lung tissues of infected LincR-PPP2R5C KO mice, there was a notable increase in the levels of type 2 cytokines [interleukin (IL)-4 and IL-5] and an increase in the number of neutrophils in both the lung tissue and bronchoalveolar lavage fluid. Mechanistically, the lack of LincR-PPP2R5C results in increased protein phosphatase 2A phosphorylation, thereby enhancing the fungicidal activity of neutrophils against Cryptococcus neoformans, with IL-4 playing a synergistic role in this process. Overall, LincR-PPP2R5C deficiency mitigated pulmonary cryptococcosis by increasing the fungicidal activity of neutrophils, which was associated with increased IL-4 levels. Our study presented specific evidence of the role of host-derived lncRNAs in the regulation of C. neoformans infection. IMPORTANCE Pulmonary cryptococcosis is a human fungal disease caused by Cryptococcus neoformans, which is common not only in immunocompromised individuals but also in patients with normal immune function. Therefore, studying the control mechanisms of pulmonary cryptococcosis is highly important. Here, we demonstrated that the deletion of LincR-PPP2R5C leads to increased killing of C. neoformans by neutrophils, thereby reducing pulmonary cryptococcal infection. These findings will greatly enhance our understanding of the mechanisms by which lncRNAs regulate the pathogenesis of C. neoformans, facilitating the use of lncRNAs in pulmonary cryptococcosis therapy.
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Affiliation(s)
- Chen Yang
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ying Gong
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
| | - Shan Liu
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
| | - Chunan Sun
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
| | - Ting Wang
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
| | - Xin Chen
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
| | - Wei Liu
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
| | - Xia Zhang
- Department of Infectious Diseases, The Affiliated Taizhou People's Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Yonglin Yang
- Department of Infectious Diseases, The Affiliated Taizhou People's Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Nanjing, China
| | - Mingshun Zhang
- Department of Immunology, National Vaccine Innovation Platform, School of Basic Medical Sciences, Nanjing Medical University, Nanjing, China
- NHC Key Laboratory of Antibody Technique, Jiangsu Key Laboratory of Pathogen Biology, Department of Immunology, Nanjing Medical University, Nanjing, China
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Shepelev N, Dontsova O, Rubtsova M. Post-Transcriptional and Post-Translational Modifications in Telomerase Biogenesis and Recruitment to Telomeres. Int J Mol Sci 2023; 24:5027. [PMID: 36902458 PMCID: PMC10003056 DOI: 10.3390/ijms24055027] [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: 02/02/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023] Open
Abstract
Telomere length is associated with the proliferative potential of cells. Telomerase is an enzyme that elongates telomeres throughout the entire lifespan of an organism in stem cells, germ cells, and cells of constantly renewed tissues. It is activated during cellular division, including regeneration and immune responses. The biogenesis of telomerase components and their assembly and functional localization to the telomere is a complex system regulated at multiple levels, where each step must be tuned to the cellular requirements. Any defect in the function or localization of the components of the telomerase biogenesis and functional system will affect the maintenance of telomere length, which is critical to the processes of regeneration, immune response, embryonic development, and cancer progression. An understanding of the regulatory mechanisms of telomerase biogenesis and activity is necessary for the development of approaches toward manipulating telomerase to influence these processes. The present review focuses on the molecular mechanisms involved in the major steps of telomerase regulation and the role of post-transcriptional and post-translational modifications in telomerase biogenesis and function in yeast and vertebrates.
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Affiliation(s)
- Nikita Shepelev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Olga Dontsova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Maria Rubtsova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
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3
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de Oliveira BCD, Shiburah ME, Paiva SC, Vieira MR, Morea EGO, da Silva MS, Alves CDS, Segatto M, Gutierrez-Rodrigues F, Borges JC, Calado RT, Cano MIN. Possible Involvement of Hsp90 in the Regulation of Telomere Length and Telomerase Activity During the Leishmania amazonensis Developmental Cycle and Population Proliferation. Front Cell Dev Biol 2021; 9:713415. [PMID: 34778247 PMCID: PMC8581162 DOI: 10.3389/fcell.2021.713415] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 09/29/2021] [Indexed: 12/29/2022] Open
Abstract
The Leishmania developmental cycle comprises three main life forms in two hosts, indicating that the parasite is continually challenged due to drastic environmental changes. The disruption of this cycle is critical for discovering new therapies to eradicate leishmaniasis, a neglected disease that affects millions worldwide. Telomeres, the physical ends of chromosomes, maintain genome stability and cell proliferation and are potential antiparasitic drug targets. Therefore, understanding how telomere length is regulated during parasite development is vital. Here, we show that telomeres form clusters spread in the nucleoplasm of the three parasite life forms. We also observed that amastigotes telomeres are shorter than metacyclic and procyclic promastigotes and that in parasites with continuous in vitro passages, telomere length increases over time. These observed differences in telomere length among parasite’s life stages were not due to lack/inhibition of telomerase since enzyme activity was detected in all parasite life stages, although the catalysis was temperature-dependent. These data led us to test if, similar to other eukaryotes, parasite telomere length maintenance could be regulated by Hsp83, the ortholog of Hsp90 in trypanosomatids, and Leishmania (LHsp90). Parasites were then treated with the Hsp90 inhibitor 17AAG. The results showed that 17AAG disturbed parasite growth, induced accumulation into G2/M phases, and telomere shortening in a time-dependent manner. It has also inhibited procyclic promastigote’s telomerase activity. Besides, LHsp90 interacts with the telomerase TERT component as shown by immunoprecipitation, strongly suggesting a new role for LHsp90 as a parasite telomerase component involved in controlling telomere length maintenance and parasite life span.
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Affiliation(s)
- Beatriz C D de Oliveira
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
| | - Mark E Shiburah
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
| | - Stepany C Paiva
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
| | - Marina R Vieira
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
| | - Edna Gicela O Morea
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
| | - Marcelo Santos da Silva
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
| | - Cristiane de Santis Alves
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
| | | | | | - Júlio C Borges
- São Carlos Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Rodrigo T Calado
- Hemocentro da Faculdade de Medicina de Ribeirão Preto, Universidade of São Paulo, São Paulo, Brazil
| | - Maria Isabel N Cano
- Department of Chemical and Biological Sciences, Institute of Biosciences, São Paulo State University (UNESP), São Paulo, Brazil
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Telomerase Biogenesis and Activities from the Perspective of Its Direct Interacting Partners. Cancers (Basel) 2020; 12:cancers12061679. [PMID: 32599885 PMCID: PMC7352425 DOI: 10.3390/cancers12061679] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/20/2020] [Accepted: 06/22/2020] [Indexed: 12/15/2022] Open
Abstract
Telomerase reverse transcriptase (TERT)—the catalytic subunit of telomerase—is reactivated in up to 90% of all human cancers. TERT is observed in heterogenous populations of protein complexes, which are dynamically regulated in a cell type- and cell cycle-specific manner. Over the past two decades, in vitro protein–protein interaction detection methods have discovered a number of endogenous TERT binding partners in human cells that are responsible for the biogenesis and functionalization of the telomerase holoenzyme, including the processes of TERT trafficking between subcellular compartments, assembly into telomerase, and catalytic action at telomeres. Additionally, TERT have been found to interact with protein species with no known telomeric functions, suggesting that these complexes may contribute to non-canonical activities of TERT. Here, we survey TERT direct binding partners and discuss their contributions to TERT biogenesis and functions. The goal is to review the comprehensive spectrum of TERT pro-malignant activities, both telomeric and non-telomeric, which may explain the prevalence of its upregulation in cancer.
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Abstract
Telomeres are specialised structures at the end of linear chromosomes. They consist of tandem repeats of the hexanucleotide sequence TTAGGG, as well as a protein complex called shelterin. Together, they form a protective loop structure against chromosome fusion and degradation. Shortening or damage to telomeres and opening of the loop induce an uncapped state that triggers a DNA damage response resulting in senescence or apoptosis.Average telomere length, usually measured in human blood lymphocytes, was thought to be a biomarker for ageing, survival and mortality. However, it becomes obvious that regulation of telomere length is very complex and involves multiple processes. For example, the "end replication problem" during DNA replication as well as oxidative stress are responsible for the shortening of telomeres. In contrast, telomerase activity can potentially counteract telomere shortening when it is able to access and interact with telomeres. However, while highly active during development and in cancer cells, the enzyme is down-regulated in most human somatic cells with a few exceptions such as human lymphocytes. In addition, telomeres can be transcribed, and the transcription products called TERRA are involved in telomere length regulation.Thus, telomere length and their integrity are regulated at many different levels, and we only start to understand this process under conditions of increased oxidative stress, inflammation and during diseases as well as the ageing process.This chapter aims to describe our current state of knowledge on telomeres and telomerase and their regulation in order to better understand their role for the ageing process.
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Identification of key genes and transcription factors in aging mesenchymal stem cells by DNA microarray data. Gene 2019; 692:79-87. [PMID: 30641220 DOI: 10.1016/j.gene.2018.12.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 12/31/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND Mesenchymal stem cells (MSCs) are multipotent cells that can be widely used in stem cell therapy. However, few studies have revealed the potential mechanisms of the changes in aging MSC. MATERIALS AND METHODS In this study, microarray data GSE35955 was downloaded from the Gene Expression Omnibus database. Then limma package in R was used to filtrate differentially expressed genes (DEGs), Transcription factors (TFs) were predicted by DCGL package. After predicting TFs, protein-protein interaction (PPI) network and TF-mediated transcriptional regulation network were constructed. The functional and pathway enrichment analysis of screened DEGs, hub genes and TFs were conducted by the DAVID. RESULTS Totally 156 up-regulated DEGs and 343 down-regulated DEGs were obtained. 6 hub genes (CTNNB1, PPP2R1A, FYN, MAPK1, PIK3C2A and EP300) were obtained from PPI network. 11 TFs (CREB1, CUX1, EGR1, EP300, FOXC1, HSF2, MEF2A, PLAU, SP1, STAT1 and USF1) for DEGs were predicted and 2 highly scored co-expression relationships (EP300-PPP2R1A and STAT1-FOXC1) were acquired from the TF-mediated transcriptional regulation network. CONCLUSIONS The discovery of the hub genes, TFs and pathways might contribute to the understanding of genetic and molecular functions of aging-related changes in MSC. Further validation studies on genes and TFs such as CTNNB1, FYN, PPP2R1A, MAPK1, EP300 and related biological processes and pathways, including adherens junction, DNA damage caused from oxidative stress, attribution of telomere, MSC differentiation and epigenetic regulation, are urgent for clinical prevention and treatment.
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7
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Gil RS, Vagnarelli P. Protein phosphatases in chromatin structure and function. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1866:90-101. [PMID: 30036566 PMCID: PMC6227384 DOI: 10.1016/j.bbamcr.2018.07.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/29/2018] [Accepted: 07/18/2018] [Indexed: 12/19/2022]
Abstract
Chromatin structure and dynamics are highly controlled and regulated processes that play an essential role in many aspects of cell biology. The chromatin transition stages and the factors that control this process are regulated by post-translation modifications, including phosphorylation. While the role of protein kinases in chromatin dynamics has been quite well studied, the nature and regulation of the counteracting phosphatases represent an emerging field but are still at their infancy. In this review we summarize the current literature on phosphatases involved in the regulation of chromatin structure and dynamics, with emphases on the major knowledge gaps that should require attention and more investigation.
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Affiliation(s)
- Raquel Sales Gil
- Colleges of Health and Life Science, Research Institute for Environment Health and Society, Brunel University London, London UB8 3PH, UK
| | - Paola Vagnarelli
- Colleges of Health and Life Science, Research Institute for Environment Health and Society, Brunel University London, London UB8 3PH, UK.
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8
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MacNeil DE, Bensoussan HJ, Autexier C. Telomerase Regulation from Beginning to the End. Genes (Basel) 2016; 7:genes7090064. [PMID: 27649246 PMCID: PMC5042394 DOI: 10.3390/genes7090064] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/25/2016] [Accepted: 08/26/2016] [Indexed: 12/11/2022] Open
Abstract
The vast body of literature regarding human telomere maintenance is a true testament to the importance of understanding telomere regulation in both normal and diseased states. In this review, our goal was simple: tell the telomerase story from the biogenesis of its parts to its maturity as a complex and function at its site of action, emphasizing new developments and how they contribute to the foundational knowledge of telomerase and telomere biology.
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Affiliation(s)
- Deanna Elise MacNeil
- Bloomfield Centre for Research in Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Côte Ste-Catherine Road, Montréal, QC H3T 1E2, Canada.
- Room M-29, Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montréal, QC H3A 0C7, Canada.
| | - Hélène Jeanne Bensoussan
- Bloomfield Centre for Research in Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Côte Ste-Catherine Road, Montréal, QC H3T 1E2, Canada.
- Room M-29, Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montréal, QC H3A 0C7, Canada.
| | - Chantal Autexier
- Bloomfield Centre for Research in Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 Côte Ste-Catherine Road, Montréal, QC H3T 1E2, Canada.
- Room M-29, Department of Anatomy and Cell Biology, McGill University, 3640 University Street, Montréal, QC H3A 0C7, Canada.
- Department of Experimental Medicine, McGill University, 1110 Pins Avenue West, Room 101, Montréal, QC H3A 1A3, Canada.
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Mallm JP, Rippe K. Aurora Kinase B Regulates Telomerase Activity via a Centromeric RNA in Stem Cells. Cell Rep 2015; 11:1667-78. [PMID: 26051938 DOI: 10.1016/j.celrep.2015.05.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 03/28/2015] [Accepted: 05/11/2015] [Indexed: 11/29/2022] Open
Abstract
Non-coding RNAs can modulate histone modifications that, at the same time, affect transcript expression levels. Here, we dissect such a network in mouse embryonic stem cells (ESCs). It regulates the activity of the reverse transcriptase telomerase, which synthesizes telomeric repeats at the chromosome ends. We find that histone H3 serine 10 phosphorylation set by Aurora kinase B (AURKB) in ESCs during the S phase of the cell cycle at centromeric and (sub)telomeric loci promotes the expression of non-coding minor satellite RNA (cenRNA). Inhibition of AURKB induces silencing of cenRNA transcription and establishment of a repressive chromatin state with histone H3 lysine 9 trimethylation and heterochromatin protein 1 accumulation. This process results in a continuous shortening of telomeres. We further show that AURKB interacts with both telomerase and cenRNA and activates telomerase in trans. Thus, in mouse ESCs, telomere maintenance is regulated via expression of cenRNA in a cell-cycle-dependent manner.
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Affiliation(s)
- Jan-Philipp Mallm
- Research Group Genome Organization and Function, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Bioquant Center, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany.
| | - Karsten Rippe
- Research Group Genome Organization and Function, Deutsches Krebsforschungszentrum (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Bioquant Center, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany.
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The role of telomerase protein TERT in Alzheimer's disease and in tau-related pathology in vitro. J Neurosci 2015; 35:1659-74. [PMID: 25632141 DOI: 10.1523/jneurosci.2925-14.2015] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The telomerase reverse transcriptase protein TERT has recently been demonstrated to have a variety of functions both in vitro and in vivo, which are distinct from its canonical role in telomere extension. In different cellular systems, TERT protein has been shown to be protective through its interaction with mitochondria. TERT has previously been found in rodent neurons, and we hypothesize that it might have a protective function in adult human brain. Here, we investigated the expression of TERT at different stages of Alzheimer's disease pathology (Braak Stages I-VI) in situ and the ability of TERT to protect against oxidative damage in an in vitro model of tau pathology. Our data reveal that TERT is expressed in vitro in mouse neurons and microglia, and in vivo in the cytoplasm of mature human hippocampal neurons and activated microglia, but is absent from astrocytes. Intriguingly, hippocampal neurons expressing TERT did not contain hyperphosphorylated tau. Vice versa, neurons that expressed high levels of pathological tau did not appear to express TERT protein. TERT protein colocalized with mitochondria in the hippocampus of Alzheimer's disease brains (Braak Stage VI), as well as in cultured neurons under conditions of oxidative stress. Our in vitro data suggest that the absence of TERT increases ROS generation and oxidative damage in neurons induced by pathological tau. Together, our findings suggest that TERT protein persists in neurons of the adult human brain, where it may have a protective role against tau pathology.
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Bastan R, Eskandari N, Sabzghabaee AM, Manian M. Serine/Threonine phosphatases: classification, roles and pharmacological regulation. Int J Immunopathol Pharmacol 2015; 27:473-84. [PMID: 25572726 DOI: 10.1177/039463201402700402] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Phosphatases are important enzymes in a variety of biochemical pathways in different cells which they catalyze opposing reactions of phosphorylation and dephosphorylation, which may modulate the function of crucial signaling proteins in different cells. This is an important mechanism in the regulation of intracellular signal transduction pathways in many cells. Phosphatases play a key role in regulating signal transduction. It is known that phosphatases are specific for cleavage of either serine-threonine or tyrosine phosphate groups. To date, numerous compounds have been identified. This paper reviews the classification, roles and pharmacological of protein serine/threonine phosphates.
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Affiliation(s)
- R Bastan
- Department of Human Vaccine, Razi-Karaj Institute, Karaj, Iran
| | - N Eskandari
- Department of Immunology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - A M Sabzghabaee
- Isfahan Clinical Toxicology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - M Manian
- Department of Immunology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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The putative tumor suppressor C53 interacts with the human telomerase reverse transcriptase hTERT and regulates telomerase activity. CHINESE SCIENCE BULLETIN-CHINESE 2014. [DOI: 10.1007/s11434-014-0184-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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