1
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Wu Z, Gu X, Zha L, Yang Q, Zhou Y, Zeng Z. Structural and functional insights into yeast Tbf1 as an atypical telomeric repeat-binding factor. Structure 2024:S0969-2126(24)00128-X. [PMID: 38677290 DOI: 10.1016/j.str.2024.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/14/2024] [Accepted: 04/02/2024] [Indexed: 04/29/2024]
Abstract
Telomeric repeat-binding factor 1 (Tbf1) has a similar architecture as the TRF family of telomeric proteins and plays important roles in both telomere homeostasis and ribosome regulation. However, the molecular basis of why Tbf1 has such different functions compared to other TRFs remains unclear. Here, we present the crystal structures of the TRF homology (TRFH) and Myb-L domains from Schizosaccharomyces pombe Tbf1 (spTbf1). TRFH-mediated homodimerization is essential for spTbf1 stability. Importantly, spTbf1TRFH lacks the conserved docking motif for interactions with telomeric proteins, explaining why spTbf1 does not participate in the assembly of the shelterin complex. Finally, structural and biochemical analyses demonstrate that TRFH and Myb-L domains as well as the loop region of spTbf1 coordinate to recognize S. pombe telomeric double-stranded DNA. Overall, our findings provide structural and functional insights into how fungi Tbf1 acts as an atypical telomeric repeat-binding factor, which helps to understand the evolution of TRFH-containing telomeric proteins.
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Affiliation(s)
- Zhenfang Wu
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
| | - Xin Gu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Lin Zha
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Qingqiu Yang
- Department of Hematology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Yuanze Zhou
- Department of Hematology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing 400038, China.
| | - Zhixiong Zeng
- Hunan Provincial Key Laboratory of the TCM Agricultural Biogenomics, Changsha Medical University, Changsha 410219, China.
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2
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Yin L, Jiang N, Li T, Zhang Y, Yuan S. Telomeric function and regulation during male meiosis in mice and humans. Andrology 2024. [PMID: 38511802 DOI: 10.1111/andr.13631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 02/26/2024] [Accepted: 03/03/2024] [Indexed: 03/22/2024]
Abstract
BACKGROUND Telomeres are unique structures situated at the ends of chromosomes. Preserving the structure and function of telomeres is essential for maintaining genomic stability and promoting genetic diversity during male meiosis in mammals. MATERIAL-METHODS This review compiled recent literature on the function and regulation of telomeres during male meiosis in both mice and humans, and also highlighted the critical roles of telomeres in reproductive biology and medicine. RESULTS-DISCUSSION Various structures, consisting of the LINC complex (SUN-KASH), SPDYA-CDK2, TTM trimer (TERB1-TERB2-MAJIN), and shelterin, are critical in controlling telomeric activities, such as nuclear envelope attachment and bouquet formation. Other than telomere-related proteins, cohesins and genes responsible for regulating telomere function are also highlighted, though the exact mechanism remains unclear. The gene-mutant mouse models with meiotic defects directly reveal the essential roles of telomeres in male meiosis. Recently reported mutant genes associated with telomere activity in clinical practice have also been illustrated in detail. CONCLUSIONS Proper regulation of telomere activities is essential for male meiosis progression in mice and humans.
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Affiliation(s)
- Lisha Yin
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Nan Jiang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tao Li
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Youzhi Zhang
- School of Pharmacy, Xianning Medical College, Hubei University of Science and Technology; Hubei Engineering Research Center of Traditional Chinese Medicine of South Hubei Province, Xianning, China
| | - Shuiqiao Yuan
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Laboratory of Animal Center, Huazhong University of Science and Technology, Wuhan, China
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3
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Yang X, Feng F, Gao D, Cai L, Wan C, Zhou X, Zeng Z. Analysis of telomere length and the relationship with neurocognitive functions in euthymic bipolar disorder: A cross-sectional pilot study. J Affect Disord 2024; 347:630-634. [PMID: 38065483 DOI: 10.1016/j.jad.2023.12.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 11/09/2023] [Accepted: 12/02/2023] [Indexed: 12/21/2023]
Abstract
BACKGROUND Telomere shortening has been considered a potential biological marker related to disease susceptibility and aging in psychiatric disorders. However, the relationship between telomere length and bipolar disorder (BD-I and BD-II) is uncertain. Moreover, whether telomere shortening is an independent factor of cognitive impairment in BD patients is still inconclusive. METHODS We explore telomere length and cognitive function in patients with bipolar disorder and the relationship between them. We enrolled three groups (35 patients with euthymic BD-I, 18 with euthymic BD-II, and 38 healthy controls). Telomere length was measured by fluorescent quantitative polymerase chain reaction (q-PCR), and cognitive function was evaluated by the MATRICS Consensus Cognitive Battery (MCCB). SPSS 24.0 was used for statistical analysis. RESULTS The telomere length of euthymic patients with BD-I and BD-II was shorter than that of healthy controls (F = 8.228, P = 0.001, η2 = 0.176). Telomere length was not significantly different between BD-I and BD-II. Compared to HCs, poor performance was detected in attention and vigilance in BD-I patients (F = 3.473, P = 0.036). Working memory was positively correlated with telomere length in BD-II patients (Beta = 0.5, P = 0.041, Adjusted R2 = 0.2). CONCLUSIONS The current study provided evidence of shortened telomere length in euthymic BD patients, indicating that telomere shortening might be a promising biomarker of susceptibility to bipolar disorder. The telomere length predicted the working memory in BD-II patients. Further studies are needed to clarify the role of accelerated aging on cognitive functioning in a young group of patients with BD.
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Affiliation(s)
- Xi Yang
- Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China.
| | - Fei Feng
- Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Dailin Gao
- The Second People's Hospital of Futian District Shenzhen, Shenzhen, China
| | - Luyao Cai
- Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Chao Wan
- Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Xudong Zhou
- Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Zhiwen Zeng
- Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
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4
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Li B. Unwrap RAP1's Mystery at Kinetoplastid Telomeres. Biomolecules 2024; 14:67. [PMID: 38254667 PMCID: PMC10813129 DOI: 10.3390/biom14010067] [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: 12/06/2023] [Revised: 12/27/2023] [Accepted: 12/27/2023] [Indexed: 01/24/2024] Open
Abstract
Although located at the chromosome end, telomeres are an essential chromosome component that helps maintain genome integrity and chromosome stability from protozoa to mammals. The role of telomere proteins in chromosome end protection is conserved, where they suppress various DNA damage response machineries and block nucleolytic degradation of the natural chromosome ends, although the detailed underlying mechanisms are not identical. In addition, the specialized telomere structure exerts a repressive epigenetic effect on expression of genes located at subtelomeres in a number of eukaryotic organisms. This so-called telomeric silencing also affects virulence of a number of microbial pathogens that undergo antigenic variation/phenotypic switching. Telomere proteins, particularly the RAP1 homologs, have been shown to be a key player for telomeric silencing. RAP1 homologs also suppress the expression of Telomere Repeat-containing RNA (TERRA), which is linked to their roles in telomere stability maintenance. The functions of RAP1s in suppressing telomere recombination are largely conserved from kinetoplastids to mammals. However, the underlying mechanisms of RAP1-mediated telomeric silencing have many species-specific features. In this review, I will focus on Trypanosoma brucei RAP1's functions in suppressing telomeric/subtelomeric DNA recombination and in the regulation of monoallelic expression of subtelomere-located major surface antigen genes. Common and unique mechanisms will be compared among RAP1 homologs, and their implications will be discussed.
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Affiliation(s)
- Bibo Li
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Arts and Sciences, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, USA;
- Case Comprehensive Cancer Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195, USA
- Center for RNA Science and Therapeutics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
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5
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Li B. Telomere maintenance in African trypanosomes. Front Mol Biosci 2023; 10:1302557. [PMID: 38074093 PMCID: PMC10704157 DOI: 10.3389/fmolb.2023.1302557] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 11/15/2023] [Indexed: 02/12/2024] Open
Abstract
Telomere maintenance is essential for genome integrity and chromosome stability in eukaryotic cells harboring linear chromosomes, as telomere forms a specialized structure to mask the natural chromosome ends from DNA damage repair machineries and to prevent nucleolytic degradation of the telomeric DNA. In Trypanosoma brucei and several other microbial pathogens, virulence genes involved in antigenic variation, a key pathogenesis mechanism essential for host immune evasion and long-term infections, are located at subtelomeres, and expression and switching of these major surface antigens are regulated by telomere proteins and the telomere structure. Therefore, understanding telomere maintenance mechanisms and how these pathogens achieve a balance between stability and plasticity at telomere/subtelomere will help develop better means to eradicate human diseases caused by these pathogens. Telomere replication faces several challenges, and the "end replication problem" is a key obstacle that can cause progressive telomere shortening in proliferating cells. To overcome this challenge, most eukaryotes use telomerase to extend the G-rich telomere strand. In addition, a number of telomere proteins use sophisticated mechanisms to coordinate the telomerase-mediated de novo telomere G-strand synthesis and the telomere C-strand fill-in, which has been extensively studied in mammalian cells. However, we recently discovered that trypanosomes lack many telomere proteins identified in its mammalian host that are critical for telomere end processing. Rather, T. brucei uses a unique DNA polymerase, PolIE that belongs to the DNA polymerase A family (E. coli DNA PolI family), to coordinate the telomere G- and C-strand syntheses. In this review, I will first briefly summarize current understanding of telomere end processing in mammals. Subsequently, I will describe PolIE-mediated coordination of telomere G- and C-strand synthesis in T. brucei and implication of this recent discovery.
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Affiliation(s)
- Bibo Li
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Arts and Sciences, Cleveland State University, Cleveland, OH, United States
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, United States
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States
- Center for RNA Science and Therapeutics, Case Western Reserve University, Cleveland, OH, United States
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6
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Sienkiewicz M, Sroka K, Binienda A, Jurk D, Fichna J. A new face of old cells: An overview about the role of senescence and telomeres in inflammatory bowel diseases. Ageing Res Rev 2023; 91:102083. [PMID: 37802318 DOI: 10.1016/j.arr.2023.102083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 10/01/2023] [Accepted: 10/02/2023] [Indexed: 10/08/2023]
Abstract
Cellular senescence is a pivotal factor contributing to aging and the pathophysiology of age-related diseases. Despite the presence of inflammation and abnormal immune system function in both inflammatory bowel diseases (IBD) and senescence, the relationship between the two remains largely unexplored. Therefore, our study aimed to investigate the intricate connection between cellular senescence, telomeres, and IBD. The review highlights the presence of senescence markers, particularly p16 and p21, in IBD patients, suggesting their potential association with disease progression and mucosal inflammation. We emphasize the critical role of macrophages in eliminating senescent cells and how disturbance in effective clearance may contribute to persistent senescence and inflammation in IBD. Additionally, we shed light on the involvement of telomeres in IBD, as their dysfunction impairs enterocyte function and disrupts colonic barrier integrity, potentially exacerbating the pathogenesis of the disease. Targeting senescence and telomere dysfunctions holds promise for the development of innovative therapeutic approaches to mitigate intestinal inflammation and alleviate symptoms in IBD patients. By unraveling the precise role of senescence in IBD, we can pave the way for the discovery of novel therapeutic interventions that effectively address the underlying mechanisms of intestinal inflammation, offering hope for improved management and treatment of IBD patients.
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Affiliation(s)
- Michał Sienkiewicz
- Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | - Kamila Sroka
- Department of Family Medicine and Public Health, University of Opole, Opole, Poland
| | - Agata Binienda
- Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland
| | - Diana Jurk
- Robert and Arlene Kogod Center On Aging, Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Jakub Fichna
- Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
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7
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Martinez S, Jones JD. A pilot study examining the relationship between chronic heroin use and telomere length among individuals of African ancestry. Pharmacol Biochem Behav 2023; 231:173631. [PMID: 37689117 PMCID: PMC10545475 DOI: 10.1016/j.pbb.2023.173631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 08/29/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023]
Abstract
BACKGROUND Prior research has suggested a possible link between heroin use and shortened telomere length (TL), a marker of cellular aging and genomic stability. We sought to replicate these findings by examining the relationship between TL and heroin use among individuals of African ancestry. METHODS This cross-sectional study examined TL among 57 participants [17.5 % female; mean age 48.0 (±6.80) years] of African ancestry with Opioid Use Disorder (OUD) and a mean heroin use duration of 18.2 (±10.7) years. Quantitative polymerase chain reaction (qPCR) was used to calculate TL as the ratio between telomere repeat copy number (T) and a single-copy gene, copy number (S). The primary dependent variable was TL (T/S Ratio) measured in kilobase pairs. Covariates included heroin use years and personality traits. Using a hybrid approach, multiple linear regression and Bayesian linear regression examined the association of chronological age, heroin use years and personality traits with TL. RESULTS The multiple linear regression model fit the data well, R2 = 0.265, F(7,49) = 2.53, p < .026. Chronological age (β = -0.36, p = .017), neuroticism (β = 0.46, p = .044), and conscientiousness (β = 0.52, p = .040) were significant predictors of TL. Bayesian linear regression provided moderate support for the alternate hypothesis that chronological age and TL are associated, BF10 = 5.77, R2 = 0.120. The posterior summary of the coefficient was M = 0.719 (SD = 0.278, 95 % credible interval [-1.28, -0.163]). CONCLUSIONS Contrary to prior studies, these findings suggest that heroin use duration may not be significantly associated with TL among individuals of African ancestry, highlighting the need for more rigorous research to elucidate the complexity of this relationship.
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Affiliation(s)
- Suky Martinez
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons and New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA.
| | - Jermaine D Jones
- Division on Substance Use Disorders, Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons and New York State Psychiatric Institute, 1051 Riverside Drive, New York, NY 10032, USA
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8
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Vijay Kumar MJ, Morales R, Tsvetkov AS. G-quadruplexes and associated proteins in aging and Alzheimer's disease. FRONTIERS IN AGING 2023; 4:1164057. [PMID: 37323535 PMCID: PMC10267416 DOI: 10.3389/fragi.2023.1164057] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 05/17/2023] [Indexed: 06/17/2023]
Abstract
Aging is a prominent risk factor for many neurodegenerative disorders, such as Alzheimer's disease (AD). Alzheimer's disease is characterized by progressive cognitive decline, memory loss, and neuropsychiatric and behavioral symptoms, accounting for most of the reported dementia cases. This disease is now becoming a major challenge and burden on modern society, especially with the aging population. Over the last few decades, a significant understanding of the pathophysiology of AD has been gained by studying amyloid deposition, hyperphosphorylated tau, synaptic dysfunction, oxidative stress, calcium dysregulation, and neuroinflammation. This review focuses on the role of non-canonical secondary structures of DNA/RNA G-quadruplexes (G4s, G4-DNA, and G4-RNA), G4-binding proteins (G4BPs), and helicases, and their roles in aging and AD. Being critically important for cellular function, G4s are involved in the regulation of DNA and RNA processes, such as replication, transcription, translation, RNA localization, and degradation. Recent studies have also highlighted G4-DNA's roles in inducing DNA double-strand breaks that cause genomic instability and G4-RNA's participation in regulating stress granule formation. This review emphasizes the significance of G4s in aging processes and how their homeostatic imbalance may contribute to the pathophysiology of AD.
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Affiliation(s)
- M. J. Vijay Kumar
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
| | - Rodrigo Morales
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
- Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O’Higgins, Santiago, Chile
| | - Andrey S. Tsvetkov
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
- The University of Texas Graduate School of Biomedical Sciences, Houston, TX, United States
- UTHealth Consortium on Aging, The University of Texas McGovern Medical School, Houston, TX, United States
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9
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Salem S, Ashaat E. Association of Relative Telomere Length and LINE-1 Methylation with Autism but not with Severity. J Autism Dev Disord 2023:10.1007/s10803-023-05965-0. [PMID: 37014460 DOI: 10.1007/s10803-023-05965-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2023] [Indexed: 04/05/2023]
Abstract
Autism is associated with genomic instability, which is regulated by telomere length (TL) and index of global methylation (LINE-1). This study will determine relative TL (RTL) and LINE-1 methylation percentage for 69 patients and 33 control subjects to evaluate their potential role as biomarkers for autism. The results displayed a significant decrease of both RTL and LINE-1 methylation in autistic cases relative to controls (P < 0.001). Analysis of receiver operating characteristics curve revealed that both of RTL and LINE-1 methylation percentage have the ability to serve as autism biomarkers (area under the curve = 0.817 and 0.889, respectively). The statistical analysis revealed positive correlation between the two biomarkers (correlation coefficient = 0.439 and P < 0.001).
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Affiliation(s)
- Sohair Salem
- Molecular Genetics & Enzymology Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt.
| | - Engy Ashaat
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
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10
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Yang X, Benny PA, Cervera-Marzal E, Wu B, Lassiter CB, Astern J, Garmire LX. Placental telomere length shortening is not associated with severe preeclampsia but the gestational age. Aging (Albany NY) 2022; 15:353-370. [PMID: 36575046 PMCID: PMC9925682 DOI: 10.18632/aging.204445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 12/09/2022] [Indexed: 12/28/2022]
Abstract
Variations in telomere length (TL) have been associated with aging, stress, and many diseases. Placenta TL is an essential molecular component influencing the outcome of birth. Previous investigations into the relationship between placenta TL and preeclampsia (PE) have produced conflicting findings. We conducted a retrospective case-control analysis in this study to address the disparity. We used placenta samples from 224 births received from Hawaii Biorepository (HiBR) between 2006 and 2013, comprising 129 healthy full-term controls and 95 severe PE samples. The average absolute placental TL was calculated using the quantitative polymerase chain reaction (qPCR) technique. We utilized multiple linear regressions to associate placental TL with severe PE and other demographic, clinical and physiological data. The outcome demonstrates that the placental TL of severe PE cases did not significantly differ from that of healthy controls. Instead, there is a strong correlation between gestational age and placenta TL shortening. Placental TL also exhibits racial differences: (1) Latino moms' TL is significantly longer than non-Latino mothers' (p=0.009). (2) Caucasian patients with severe PE have shorter TL than non-Caucasian patients (p=0.0037). This work puts the long-standing question of whether severe PE influences placental TL to rest. Placental TL is not related to severe PE but is negatively associated with gestational age and is also affected by race.
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Affiliation(s)
- Xiaotong Yang
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Paula A. Benny
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Elorri Cervera-Marzal
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Biyu Wu
- Department of Nutritional Science, University of Hawaii, Honolulu, HI 96822, USA
| | - Cameron B. Lassiter
- Epidemiology Program, University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Joshua Astern
- University of Hawai’i Biorepository John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA
| | - Lana X. Garmire
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
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11
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Aschacher T, Geisler D, Lenz V, Aschacher O, Winkler B, Schaefer AK, Mitterbauer A, Wolf B, Enzmann FK, Messner B, Laufer G, Ehrlich MP, Grabenwöger M, Bergmann M. Impacts of Telomeric Length, Chronic Hypoxia, Senescence, and Senescence-Associated Secretory Phenotype on the Development of Thoracic Aortic Aneurysm. Int J Mol Sci 2022; 23:ijms232415498. [PMID: 36555139 PMCID: PMC9779024 DOI: 10.3390/ijms232415498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/18/2022] [Accepted: 11/30/2022] [Indexed: 12/13/2022] Open
Abstract
Thoracic aortic aneurysm (TAA) is an age-related and life-threatening vascular disease. Telomere shortening is a predictor of age-related diseases, and its progression is associated with premature vascular disease. The aim of the present work was to investigate the impacts of chronic hypoxia and telomeric DNA damage on cellular homeostasis and vascular degeneration of TAA. We analyzed healthy and aortic aneurysm specimens (215 samples) for telomere length (TL), chronic DNA damage, and resulting changes in cellular homeostasis, focusing on senescence and apoptosis. Compared with healthy thoracic aorta (HTA), patients with tricuspid aortic valve (TAV) showed telomere shortening with increasing TAA size, in contrast to genetically predisposed bicuspid aortic valve (BAV). In addition, TL was associated with chronic hypoxia and telomeric DNA damage and with the induction of senescence-associated secretory phenotype (SASP). TAA-TAV specimens showed a significant difference in SASP-marker expression of IL-6, NF-κB, mTOR, and cell-cycle regulators (γH2AX, Rb, p53, p21), compared to HTA and TAA-BAV. Furthermore, we observed an increase in CD163+ macrophages and a correlation between hypoxic DNA damage and the number of aortic telocytes. We conclude that chronic hypoxia is associated with telomeric DNA damage and the induction of SASP in a diseased aortic wall, promising a new therapeutic target.
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Affiliation(s)
- Thomas Aschacher
- Department of Cardiovascular Surgery, Clinic Floridsdorf and Karl Landsteiner Institute for Cardio-Vascular Research, 1210 Vienna, Austria
- Department of Cardiac Surgery, Medical University of Vienna, 1090 Vienna, Austria
- Correspondence: ; Tel.: +43-1-277-00-74316
| | - Daniela Geisler
- Department of Cardiovascular Surgery, Clinic Floridsdorf and Karl Landsteiner Institute for Cardio-Vascular Research, 1210 Vienna, Austria
| | - Verena Lenz
- Department of Cardiovascular Surgery, Clinic Floridsdorf and Karl Landsteiner Institute for Cardio-Vascular Research, 1210 Vienna, Austria
| | - Olivia Aschacher
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Bernhard Winkler
- Department of Cardiovascular Surgery, Clinic Floridsdorf and Karl Landsteiner Institute for Cardio-Vascular Research, 1210 Vienna, Austria
- Faculty of Medicine, Sigmund Freud Private University of Vienna, 1030 Vienna, Austria
| | | | - Andreas Mitterbauer
- Department of General Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Brigitte Wolf
- Department of General Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Florian K. Enzmann
- Department of Vascular Surgery, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Barbara Messner
- Department of Cardiac Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Günther Laufer
- Department of Cardiac Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Marek P. Ehrlich
- Department of Cardiac Surgery, Medical University of Vienna, 1090 Vienna, Austria
| | - Martin Grabenwöger
- Department of Cardiovascular Surgery, Clinic Floridsdorf and Karl Landsteiner Institute for Cardio-Vascular Research, 1210 Vienna, Austria
- Faculty of Medicine, Sigmund Freud Private University of Vienna, 1030 Vienna, Austria
| | - Michael Bergmann
- Department of General Surgery, Medical University of Vienna, 1090 Vienna, Austria
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12
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Akinnibosun OA, Maier MC, Eales J, Tomaszewski M, Charchar FJ. Telomere therapy for chronic kidney disease. Epigenomics 2022; 14:1039-1054. [PMID: 36177720 DOI: 10.2217/epi-2022-0073] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Chronic kidney disease (CKD) is estimated to affect almost 10% of individuals worldwide and is one of the leading causes of morbidity and mortality. Renal fibrosis, a central pathway in CKD progression (irrespective of etiology), is associated with shortened or dysfunctional telomeres in animal studies. Telomeres are specialized nucleoprotein structures located at the chromosome end that maintain genomic integrity. The mechanisms of associations between telomere length and CKD have not yet been fully elucidated, however, CKD patients with shorter telomere length may have decreased renal function and a higher mortality rate. A plethora of ongoing research has focused on possible therapeutic applications of telomeres with the overall goal to preserve telomere length as a therapy to treat CKD.
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Affiliation(s)
| | - Michelle C Maier
- Health Innovation and Transformation Centre, Federation University Australia, Ballarat, Victoria, Australia
| | - James Eales
- Division of Cardiovascular Sciences, University of Manchester, Manchester, UK
| | - Maciej Tomaszewski
- Division of Cardiovascular Sciences, University of Manchester, Manchester, UK.,Manchester Heart Centre and Manchester Academic Health Science Centre, Manchester University NHS Foundation Trust, Manchester, UK
| | - Fadi J Charchar
- Health Innovation and Transformation Centre, Federation University Australia, Ballarat, Victoria, Australia.,Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,Department of Anatomy and Physiology, University of Melbourne, Melbourne, Victoria, Australia
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13
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Sun H, Wu Z, Zhou Y, Lu Y, Lu H, Chen H, Shi S, Zeng Z, Wu J, Lei M. Structural insights into Pot1-ssDNA, Pot1-Tpz1 and Tpz1-Ccq1 Interactions within fission yeast shelterin complex. PLoS Genet 2022; 18:e1010308. [PMID: 35849625 PMCID: PMC9333443 DOI: 10.1371/journal.pgen.1010308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 07/28/2022] [Accepted: 06/22/2022] [Indexed: 11/30/2022] Open
Abstract
The conserved shelterin complex caps chromosome ends to protect telomeres and regulate telomere replication. In fission yeast Schizosaccharomyces pombe, shelterin consists of telomeric single- and double-stranded DNA-binding modules Pot1-Tpz1 and Taz1-Rap1 connected by Poz1, and a specific component Ccq1. While individual structures of the two DNA-binding OB folds of Pot1 (Pot1OB1-GGTTAC and Pot1OB2-GGTTACGGT) are available, structural insight into recognition of telomeric repeats with spacers by the complete DNA-binding domain (Pot1DBD) remains an open question. Moreover, structural information about the Tpz1-Ccq1 interaction requires to be revealed for understanding how the specific component Ccq1 of S. pombe shelterin is recruited to telomeres to function as an interacting hub. Here, we report the crystal structures of Pot1DBD-single-stranded-DNA, Pot1372-555-Tpz1185-212 and Tpz1425-470-Ccq1123-439 complexes and propose an integrated model depicting the assembly mechanism of the shelterin complex at telomeres. The structure of Pot1DBD-DNA unveils how Pot1 recognizes S. pombe degenerate telomeric sequences. Our analyses of Tpz1-Ccq1 reveal structural basis for the essential role of the Tpz1-Ccq1 interaction in telomere recruitment of Ccq1 that is required for telomere maintenance and telomeric heterochromatin formation. Overall, our findings provide valuable structural information regarding interactions within fission yeast shelterin complex at 3’ ss telomeric overhang. Telomeres, composed of repetitive DNA sequences and specialized proteins, are protective structures at the ends of linear chromosomes. The telomere structure is essential for the maintenance of genome integrity and stability, and telomere dysfunction has been linked to human development, aging, cancer and a variety of degenerative diseases. An evolutionarily conserved multiple-protein complex called shelterin plays versatile roles in telomere homeostasis regulation, end protection and heterochromatin establishment. However, the highly flexible nature of shelterin complex has greatly impeded our structural and functional understanding for this important complex. In fission yeast, structures of the shelterin dsDNA-binding protein subcomplex Taz1-Rap1 and the bridge subcomplex Tpz1-Poz1-Rap1 are available. Although individual OB-fold subdomains structures have been characterized, structural information about the complete Pot1DBD bound to telomeric repeats with spacers remains to be revealed. Here, by determining the crystal structures of the telomeric overhang binding Pot1DBD-ssDNA, Pot1372-555-Tpz1185-212 and Tpz1425-470-Ccq1123-439 subcomplexes, we provide structural basis not only for the recognition of S. pombe degenerate telomeric sequences by Pot1, but also for the essential function of the Tpz1-Ccq1 interaction in Ccq1 recruitment to telomeres for telomere maintenance and telomeric heterochromatin formation. These findings provide an integrated model depicting the assembly mechanism of the shelterin complex at telomeres and its multiple roles in telomere biology.
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Affiliation(s)
- Hong Sun
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
- University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Zhenfang Wu
- Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Precision Medicine, Shanghai, China
- * E-mail: (ZW); (ZZ); (JW); (ML)
| | - Yuanze Zhou
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Yanjia Lu
- Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Precision Medicine, Shanghai, China
| | - Huaisheng Lu
- Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Precision Medicine, Shanghai, China
| | - Hongwen Chen
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Shaohua Shi
- Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Precision Medicine, Shanghai, China
| | - Zhixiong Zeng
- Shandong Provincial Key Laboratory of Microbial Engineering, College of Bioengineering, Qilu University of Technology, Shandong, China
- * E-mail: (ZW); (ZZ); (JW); (ML)
| | - Jian Wu
- Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Precision Medicine, Shanghai, China
- * E-mail: (ZW); (ZZ); (JW); (ML)
| | - Ming Lei
- Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Institute of Precision Medicine, Shanghai, China
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- * E-mail: (ZW); (ZZ); (JW); (ML)
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14
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Mushtaq I, Bhat GR, Rah B, Besina S, Zahoor S, Wani MA, Shah MA, Bashir S, Farooq M, Rather RA, Afroze D. Telomere Attrition With Concomitant hTERT Overexpression Involved in the Progression of Gastric Cancer May Have Prognostic and Clinical Implications in High-Risk Population Group From North India. Front Oncol 2022; 12:919351. [PMID: 35912187 PMCID: PMC9326504 DOI: 10.3389/fonc.2022.919351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 06/13/2022] [Indexed: 11/25/2022] Open
Abstract
Genetic instabilities exacerbated by the dysfunction of telomeres can lead to the development of cancer. Nearly 90% of all human malignancies are linked with telomere dysregulation and overexpression of telomerase, an enzyme that catalyzes the synthesis of telomeric DNA repeats at the ends of chromosomes. The burden of gastric cancer continues to inflict a deterring impact on the global health scenario, accounting for over one million new cases in 2020. The disease is asymptomatic in its early stages of progression, which is attributed to the poor prognosis and overall surge in mortality rate worldwide. Exploiting telomere physiology can provide extensive mechanistic insight into telomere-associated gastric cancer progression and its use as a target in a variety of therapeutic interventions. In this study, we aimed to evaluate the clinical implications of c-Myc, human telomerase reverse transcriptase (hTERT) expression, and telomere length in patients with gastric cancer. A total of 57 gastric cancer cases and adjacent controls were included in the study. RT-PCR and immunohistochemistry were used to assess the expression levels of c-Myc and hTERT. The relative telomere length was measured by MMQPCR using the Cawthon method. Our results indicated that the shorter telomere and increased hTERT expression were associated with gastric cancer progression. The study also highlighted the role of short telomeres and increased expression of hTERT in gastric cancer progression and its association with various etiological risk factors, transcriptional activators, and overall survival among the ethnic Kashmiri population of North India.
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Affiliation(s)
- Ifra Mushtaq
- Advanced Centre for Human Genetics, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Gh Rasool Bhat
- Advanced Centre for Human Genetics, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Bilal Rah
- Advanced Centre for Human Genetics, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Syed Besina
- Department of Pathology, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Sheikh Zahoor
- Department of Surgical Oncology, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Muneer A. Wani
- Department of General Surgery, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Mubashir A. Shah
- Department of General Surgery, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Sadaf Bashir
- Advanced Centre for Human Genetics, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Muzamil Farooq
- Advanced Centre for Human Genetics, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Rafiq A. Rather
- Advanced Centre for Human Genetics, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
| | - Dil Afroze
- Advanced Centre for Human Genetics, Sher-I- Kashmir Institute of Medical Sciences, Srinagar, India
- *Correspondence: Dil Afroze,
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15
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Shu H, Zhang R, Xiao K, Yang J, Sun X. G-Quadruplex-Binding Proteins: Promising Targets for Drug Design. Biomolecules 2022; 12:biom12050648. [PMID: 35625576 PMCID: PMC9138358 DOI: 10.3390/biom12050648] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 12/31/2022] Open
Abstract
G-quadruplexes (G4s) are non-canonical secondary nucleic acid structures. Sequences with the potential to form G4s are abundant in regulatory regions of the genome including telomeres, promoters and 5′ non-coding regions, indicating they fulfill important genome regulatory functions. Generally, G4s perform various biological functions by interacting with proteins. In recent years, an increasing number of G-quadruplex-binding proteins have been identified with biochemical experiments. G4-binding proteins are involved in vital cellular processes such as telomere maintenance, DNA replication, gene transcription, mRNA processing. Therefore, G4-binding proteins are also associated with various human diseases. An intensive study of G4-protein interactions provides an attractive approach for potential therapeutics and these proteins can be considered as drug targets for novel medical treatment. In this review, we present biological functions and structural properties of G4-binding proteins, and discuss how to exploit G4-protein interactions to develop new therapeutic targets.
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16
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Libertini G, Shubernetskaya O, Corbi G, Ferrara N. Is Evidence Supporting the Subtelomere-Telomere Theory of Aging? BIOCHEMISTRY. BIOKHIMIIA 2021; 86:1526-1539. [PMID: 34937532 DOI: 10.1134/s0006297921120026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The telomere theory tries to explain cellular mechanisms of aging as mainly caused by telomere shortening at each duplication. The subtelomere-telomere theory overcomes various shortcomings of telomere theory by highlighting the essential role of subtelomeric DNA in aging mechanisms. The present work illustrates and deepens the correspondence between assumptions and implications of subtelomere-telomere theory and experimental results. In particular, it is investigated the evidence regarding the relationships between aging and (i) epigenetic modifications; (ii) oxidation and inflammation; (iii) telomere protection; (iv) telomeric heterochromatin hood; (v) gradual cell senescence; (vi) cell senescence; and (vii) organism decline with telomere shortening. The evidence appears broadly in accordance or at least compatible with the description and implications of the subtelomere-telomere theory. In short, phenomena of cellular aging, by which the senescence of the whole organism is determined in various ways, appear substantially dependent on epigenetic modifications regulated by the subtelomere-telomere-telomeric hood-telomerase system. These phenomena appear to be not random, inevitable, and irreversible but rather induced and regulated by genetically determined mechanisms, and modifiable and reversible by appropriate methods. All this supports the thesis that aging is a genetically programmed and regulated phenoptotic phenomenon and is against the opposite thesis of aging as caused by random and inevitable degenerative factors.
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Affiliation(s)
- Giacinto Libertini
- Member of the Italian Society for Evolutionary Biology (SIBE), Asti, 14100, Italy. .,Department of Translational Medical Sciences, Federico II University of Naples, Naples, 80131, Italy
| | - Olga Shubernetskaya
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, 117997, Russia.
| | - Graziamaria Corbi
- Department of Medicine and Health Sciences, University of Molise, Campobasso, 86100, Italy. .,Italian Society of Gerontology and Geriatrics (SIGG), Firenze, 50129, Italy
| | - Nicola Ferrara
- Department of Translational Medical Sciences, Federico II University of Naples, Naples, 80131, Italy. .,Istituti Clinici Scientifici Maugeri SPA - Società Benefit, IRCCS, Telese Terme, BN, 82037, Italy
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17
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Zipper head mechanism of telomere synthesis by human telomerase. Cell Res 2021; 31:1275-1290. [PMID: 34782750 PMCID: PMC8648750 DOI: 10.1038/s41422-021-00586-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 10/08/2021] [Indexed: 11/08/2022] Open
Abstract
Telomerase, a multi-subunit ribonucleoprotein complex, is a unique reverse transcriptase that catalyzes the processive addition of a repeat sequence to extend the telomere end using a short fragment of its own RNA component as the template. Despite recent structural characterizations of human and Tetrahymena telomerase, it is still a mystery how telomerase repeatedly uses its RNA template to synthesize telomeric DNA. Here, we report the cryo-EM structure of human telomerase holoenzyme bound with telomeric DNA at resolutions of 3.5 Å and 3.9 Å for the catalytic core and biogenesis module, respectively. The structure reveals that a leucine residue Leu980 in telomerase reverse transcriptase (TERT) catalytic subunit functions as a zipper head to limit the length of the short primer-template duplex in the active center. Moreover, our structural and computational analyses suggest that TERT and telomerase RNA (hTR) are organized to harbor a preformed active site that can accommodate short primer-template duplex substrates for catalysis. Furthermore, our findings unveil a double-fingers architecture in TERT that ensures nucleotide addition processivity of human telomerase. We propose that the zipper head Leu980 is a structural determinant for the sequence-based pausing signal of DNA synthesis that coincides with the RNA element-based physical template boundary. Functional analyses unveil that the non-glycine zipper head plays an essential role in both telomerase repeat addition processivity and telomere length homeostasis. In addition, we also demonstrate that this zipper head mechanism is conserved in all eukaryotic telomerases. Together, our study provides an integrated model for telomerase-mediated telomere synthesis.
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18
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Watson JM, Trieb J, Troestl M, Renfrew K, Mandakova T, Fulnecek J, Shippen DE, Riha K. A hypomorphic allele of telomerase uncovers the minimal functional length of telomeres in Arabidopsis. Genetics 2021; 219:6339584. [PMID: 34849882 DOI: 10.1093/genetics/iyab126] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 07/23/2021] [Indexed: 12/23/2022] Open
Abstract
Despite the essential requirement of telomeric DNA for genome stability, the length of telomere tracts between species substantially differs, raising the question of the minimal length of telomeric DNA necessary for proper function. Here, we address this question using a hypomorphic allele of the telomerase catalytic subunit, TERT. We show that although this construct partially restored telomerase activity to a tert mutant, telomeres continued to shorten over several generations, ultimately stabilizing at a bimodal size distribution. Telomeres on two chromosome arms were maintained at a length of 1 kb, while the remaining telomeres were maintained at 400 bp. The longest telomeres identified in this background were also significantly longer in wild-type populations, suggesting cis-acting elements on these arms either promote telomerase processivity or recruitment. Genetically disrupting telomerase processivity in this background resulted in immediate lethality. Thus, telomeres of 400 bp are both necessary and sufficient for Arabidopsis viability. As this length is the estimated minimal length for t-loop formation, our data suggest that telomeres long enough to form a t-loop constitute the minimal functional length.
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Affiliation(s)
- J Matthew Watson
- Gregor Mendel Institute of Plant Molecular Biology, Austrian Academy of Sciences, 1030 Vienna, Austria
| | - Johanna Trieb
- Gregor Mendel Institute of Plant Molecular Biology, Austrian Academy of Sciences, 1030 Vienna, Austria
| | - Martina Troestl
- Gregor Mendel Institute of Plant Molecular Biology, Austrian Academy of Sciences, 1030 Vienna, Austria
| | - Kyle Renfrew
- Department of Biochemistry, Texas A&M University, College Station, TX 77840, USA
| | - Terezie Mandakova
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | - Jaroslav Fulnecek
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | - Dorothy E Shippen
- Department of Biochemistry, Texas A&M University, College Station, TX 77840, USA
| | - Karel Riha
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
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19
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Ackerson SM, Romney C, Schuck PL, Stewart JA. To Join or Not to Join: Decision Points Along the Pathway to Double-Strand Break Repair vs. Chromosome End Protection. Front Cell Dev Biol 2021; 9:708763. [PMID: 34322492 PMCID: PMC8311741 DOI: 10.3389/fcell.2021.708763] [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: 05/12/2021] [Accepted: 06/17/2021] [Indexed: 01/01/2023] Open
Abstract
The regulation of DNA double-strand breaks (DSBs) and telomeres are diametrically opposed in the cell. DSBs are considered one of the most deleterious forms of DNA damage and must be quickly recognized and repaired. Telomeres, on the other hand, are specialized, stable DNA ends that must be protected from recognition as DSBs to inhibit unwanted chromosome fusions. Decisions to join DNA ends, or not, are therefore critical to genome stability. Yet, the processing of telomeres and DSBs share many commonalities. Accordingly, key decision points are used to shift DNA ends toward DSB repair vs. end protection. Additionally, DSBs can be repaired by two major pathways, namely homologous recombination (HR) and non-homologous end joining (NHEJ). The choice of which repair pathway is employed is also dictated by a series of decision points that shift the break toward HR or NHEJ. In this review, we will focus on these decision points and the mechanisms that dictate end protection vs. DSB repair and DSB repair choice.
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Affiliation(s)
- Stephanie M Ackerson
- Department of Biological Sciences, University of South Carolina, Columbia, SC, United States
| | - Carlan Romney
- Department of Biological Sciences, University of South Carolina, Columbia, SC, United States
| | - P Logan Schuck
- Department of Biological Sciences, University of South Carolina, Columbia, SC, United States
| | - Jason A Stewart
- Department of Biological Sciences, University of South Carolina, Columbia, SC, United States
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20
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Kim EJ, Koh SH, Ha J, Na DL, Seo SW, Kim HJ, Park KW, Lee JH, Roh JH, Kwon JC, Yoon SJ, Jung NY, Jeong JH, Jang JW, Kim HJ, Park KH, Choi SH, Kim S, Park YH, Kim BC, Kim YE, Kwon HS, Park HH, Jin JH. Increased telomere length in patients with frontotemporal dementia syndrome. J Neurol Sci 2021; 428:117565. [PMID: 34311139 DOI: 10.1016/j.jns.2021.117565] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 06/22/2021] [Accepted: 07/01/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Telomeres are repetitive DNA sequences of TTAGGG at the ends of chromosomes. Many studies have shown that telomere shortening is associated with aging-related diseases, such as cardiovascular diseases, hypertension, diabetes, cancer, and various neurodegenerative diseases, including Alzheimer's disease, vascular dementia, Parkinson's disease, and dementia with Lewy bodies. However, changes in telomere length (TL) in patients with frontotemporal dementia (FTD) syndrome are unclear. Accordingly, in this study, we assessed TL in blood samples from patients with FTD syndrome. METHODS Absolute TL was measured in peripheral blood leukocytes from 53 patients with FTD syndromes (25 with behavioral variant FTD, 19 with semantic variant primary progressive aphasia [PPA], six with nonfluent/agrammatic variant PPA, and three with amyotrophic lateral sclerosis [ALS] plus) and 28 cognitively unimpaired (CU) controls using terminal restriction fragment analysis. RESULTS TL was significantly longer in the FTD group than in the CU group. All FTD subtypes had significantly longer TL than controls. There were no significant differences in TL among FTD syndromes. No significant correlations were found between TL and demographic factors in the FTD group. CONCLUSIONS Longer telomeres were associated with FTD syndrome, consistent with a recent report demonstrating that longer telomeres are related to ALS. Therefore, our results may support a shared biology between FTD and ALS. More studies with larger sample sizes are needed.
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Affiliation(s)
- Eun-Joo Kim
- Department of Neurology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan, Republic of Korea
| | - Seong-Ho Koh
- Department of Neurology, Hanyang University College of Medicine, Gyeonggi-do, Republic of Korea.
| | - Jungsoon Ha
- Department of Neurology, Hanyang University College of Medicine, Gyeonggi-do, Republic of Korea; GemVax & Kael Co., Ltd, Gyeonggi-do, Republic of Korea
| | - Duk L Na
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Sang Won Seo
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hee-Jin Kim
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Kyung Won Park
- Department of Neurology, Dong-A Medical Center, Dong-A University College of Medicine, Busan, Republic of Korea
| | - Jae-Hong Lee
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jee Hoon Roh
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jay C Kwon
- Department of Neurology, Changwon Fatima Hospital, Changwon, Republic of Korea
| | - Soo Jin Yoon
- Department of Neurology, Eulgi University Hospital, Daejeon, Republic of Korea
| | - Na-Yeon Jung
- Department of Neurology, Pusan National University Yangsan Hospital, Research Institute for Convergence of Biomedical Science and Technology, Busan, Republic of Korea
| | - Jee H Jeong
- Department of Neurology, Ewha Womans University Hospital, Seoul, Republic of Korea
| | - Jae-Won Jang
- Department of Neurology, Kangwon National University Hospital, Chuncheon, Republic of Korea
| | - Hee-Jin Kim
- Department of Neurology, Hanyang University College of Medicine, Seoul, Republic of Korea
| | - Kee Hyung Park
- Department of Neurology, Gachon University Gil Hospital, Incheon, Republic of Korea
| | - Seong Hye Choi
- Department of Neurology, Inha University School of Medicine, Incheon, Republic of Korea
| | - SangYun Kim
- Department of Neurology, Seoul National University College of Medicine and Clinical Neuroscience Center, Seoul National University Bundang Hospital, Gyeonggi-do, Republic of Korea
| | - Young Ho Park
- Department of Neurology, Seoul National University College of Medicine and Clinical Neuroscience Center, Seoul National University Bundang Hospital, Gyeonggi-do, Republic of Korea
| | - Byeong C Kim
- Department of Neurology, Chonnam National University Medical School, Chonnam National University Hospital, Gwangju, Republic of Korea
| | - Young-Eun Kim
- Department of Laboratory Medicine, Hanyang University College of Medicine, Seoul, Republic of Korea
| | - Hyuk Sung Kwon
- Department of Neurology, Hanyang University College of Medicine, Gyeonggi-do, Republic of Korea
| | - Hyun-Hee Park
- Department of Neurology, Hanyang University College of Medicine, Gyeonggi-do, Republic of Korea
| | - Jeong-Hwa Jin
- Department of Neurology, Hanyang University College of Medicine, Gyeonggi-do, Republic of Korea
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21
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Miner AE, Graves JS. What telomeres teach us about MS. Mult Scler Relat Disord 2021; 54:103084. [PMID: 34371369 DOI: 10.1016/j.msard.2021.103084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 05/14/2021] [Accepted: 06/09/2021] [Indexed: 02/03/2023]
Abstract
While the precise mechanisms driving progressive forms of MS are not fully understood, patient age has clear impact on disease phenotype. The very young with MS have high relapse rates and virtually no progressive disease, whereas older patients tend to experience more rapid disability accumulation with few relapses. Defining a patient's biological age may offer more precision in determining the role of aging processes in MS phenotype and pathophysiology than just working with an individual's birthdate. The most well recognized measurement of an individual's "biological clock" is telomere length (TL). While TL may differ across tissue types in an individual, most cells TL correlate well with leukocyte TL (LTL), which is the most common biomarker used for aging. LTL has been associated with risk for aging related diseases and most recently with higher levels of disability and brain atrophy in people living with MS. LTL explains 15% of the overall association of chronological age with MS disability level. While LTL may be used just as a biomarker of overall somatic aging processes, triggering of the DNA damage response by telomere attrition leads to senescence pathways that are likely highly relevant to a chronic autoimmune disease. Considering reproductive aging factors, particularly ovarian aging in women, which correlates with LTL and oocyte telomere length, may complement measurements of somatic aging in understanding MS progression. The key to stopping non-relapse related progression in MS might lie in targeting pathways related to biological aging effects on the immune and nervous systems.
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Affiliation(s)
- Annalise E Miner
- Department of Neurosciences, University of California, San Diego, USA
| | - Jennifer S Graves
- Department of Neurosciences, University of California, San Diego, USA.
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22
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Khodadadi E, Mir SM, Memar MY, Sadeghi H, Kashiri M, Faeghiniya M, Jamalpoor Z, Sheikh Arabi M. Shelterin complex at telomeres: Roles in cancers. GENE REPORTS 2021. [DOI: 10.1016/j.genrep.2021.101174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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Habib I, Khan S, Mohammad T, Hussain A, Alajmi MF, Rehman T, Anjum F, Hassan MI. Impact of non-synonymous mutations on the structure and function of telomeric repeat binding factor 1. J Biomol Struct Dyn 2021; 40:9053-9066. [PMID: 33982644 DOI: 10.1080/07391102.2021.1922313] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Telomeric repeat binding factor 1 (TRF1) is one of the major components of the shelterin complex. It directly binds to the telomere and controls its function by regulating the telomerase acting on it. Several variations are reported in the TRF1 gene; some are associated with variety of diseases. Here, we have studied the structural and functional significance of these variations in the TRFH domain of TRF1. We have used cutting-edge computational methods such as SIFT, PolyPhen-2, PROVEAN, Mutation Assessor, mCSM, SDM, STRUM, MAESTRO, and DUET to predict the effects of 124 mutations in the TRFH domain of TRF1. Out of 124 mutations, we have identified 12 deleterious mutations with high confidence based on their prediction. To see the impact of the finally selected mutations on the structure and stability of TRF1, all-atom molecular dynamics (MD) simulations on TRF1-Wild type (WT), L79R and P150R mutants for 200 ns were carried out. A significant conformational change in the structure of the P150R mutant was observed. Our integrated computational study provides a comprehensive understanding of structural changes in TRF1 incurred due to the mutations and subsequent function, leading to the progression of many diseases.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Insan Habib
- Department of Computer Science, Jamia Millia Islamia, New Delhi, India
| | - Shama Khan
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch, South Africa
| | - Taj Mohammad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Afzal Hussain
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Mohamed F Alajmi
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Tabish Rehman
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Farah Anjum
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taif University, Taif, Saudi Arabia
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
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24
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Libertini G, Corbi G, Nicola F. Importance and Meaning of TERRA Sequences for Aging Mechanisms. BIOCHEMISTRY (MOSCOW) 2021; 85:1505-1517. [PMID: 33705290 DOI: 10.1134/s0006297920120044] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Any theory suggesting an adaptive meaning for aging implicitly postulates the existence of specific mechanisms, genetically determined and modulated, causing progressive decline of an organism. According to the subtelomere-telomere theory, each telomere is covered by a hood formed in the first cell of an organism having a size preserved at each subsequent duplication. Telomere shortening, which is quantitatively different for each cell type according to the telomerase regulation, causes the hood to slide on the subtelomere repressing it by the telomeric position effect. At this point, the theory postulates existence of subtelomeric regulatory sequences, whose progressive transcriptional repression by the hood should cause cellular alterations that would be the likely determinant of aging manifestations. However, sequences with characteristics of these hypothetical sequences have already been described and documented. They are the [sub]TElomeric Repeat-containing RNA (TERRA) sequences. The repression of TERRA sequences causes progressively: (i) down- or up-regulation of many other regulatory sequences; (ii) increase in the probability of activation of cell senescence program (blockage of the ability to replicate and very significant alterations of the cellular functions). When cell senescence program has not been triggered and the repression is partial, there is a partial alteration of the cellular functions that is easily reversible by telomerase activation. Location of the extremely important sequences in chromosomal parts that are most vulnerable to repression by the telomeric hood is evolutionarily unjustifiable if aging is not considered adaptive: this location must be necessarily adaptive with the specific function of determining aging of the cell and consequently of the whole organism.
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Affiliation(s)
- G Libertini
- Independent researcher, member of the Italian Society for Evolutionary Biology, Asti, 14100, Italy.
| | - G Corbi
- Department of Medicine and Health Sciences, University of Molise, Campobasso, 86100, Italy.,Italian Society of Gerontology and Geriatrics (SIGG), Firenze, 50129, Italy
| | - F Nicola
- Department of Translational Medical Sciences, Federico II University of Naples, Naples, 80131, Italy.,Istituti Clinici Scientifici Maugeri SPA - Società Benefit, IRCCS, Telese Terme, BN, 82037, Italy
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25
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Monsen RC, Chakravarthy S, Dean WL, Chaires JB, Trent JO. The solution structures of higher-order human telomere G-quadruplex multimers. Nucleic Acids Res 2021; 49:1749-1768. [PMID: 33469644 PMCID: PMC7897503 DOI: 10.1093/nar/gkaa1285] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/21/2020] [Accepted: 01/13/2021] [Indexed: 12/17/2022] Open
Abstract
Human telomeres contain the repeat DNA sequence 5′-d(TTAGGG), with duplex regions that are several kilobases long terminating in a 3′ single-stranded overhang. The structure of the single-stranded overhang is not known with certainty, with disparate models proposed in the literature. We report here the results of an integrated structural biology approach that combines small-angle X-ray scattering, circular dichroism (CD), analytical ultracentrifugation, size-exclusion column chromatography and molecular dynamics simulations that provide the most detailed characterization to date of the structure of the telomeric overhang. We find that the single-stranded sequences 5′-d(TTAGGG)n, with n = 8, 12 and 16, fold into multimeric structures containing the maximal number (2, 3 and 4, respectively) of contiguous G4 units with no long gaps between units. The G4 units are a mixture of hybrid-1 and hybrid-2 conformers. In the multimeric structures, G4 units interact, at least transiently, at the interfaces between units to produce distinctive CD signatures. Global fitting of our hydrodynamic and scattering data to a worm-like chain (WLC) model indicates that these multimeric G4 structures are semi-flexible, with a persistence length of ∼34 Å. Investigations of its flexibility using MD simulations reveal stacking, unstacking, and coiling movements, which yield unique sites for drug targeting.
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Affiliation(s)
- Robert C Monsen
- Department of Biochemistry & Molecular Genetics, University of Louisville Medical School, Louisville, KY 40202, USA
| | - Srinivas Chakravarthy
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological Chemical and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - William L Dean
- James Graham Brown Cancer Center, University of Louisville Medical School, Louisville, KY 40202, USA
| | - Jonathan B Chaires
- Department of Biochemistry & Molecular Genetics, University of Louisville Medical School, Louisville, KY 40202, USA.,James Graham Brown Cancer Center, University of Louisville Medical School, Louisville, KY 40202, USA.,Department of Medicine, University of Louisville Medical School, Louisville, KY 40202, USA
| | - John O Trent
- Department of Biochemistry & Molecular Genetics, University of Louisville Medical School, Louisville, KY 40202, USA.,James Graham Brown Cancer Center, University of Louisville Medical School, Louisville, KY 40202, USA.,Department of Medicine, University of Louisville Medical School, Louisville, KY 40202, USA
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26
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McGurk MP, Dion-Côté AM, Barbash DA. Rapid evolution at the Drosophila telomere: transposable element dynamics at an intrinsically unstable locus. Genetics 2021; 217:iyaa027. [PMID: 33724410 PMCID: PMC8045721 DOI: 10.1093/genetics/iyaa027] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/03/2020] [Indexed: 12/26/2022] Open
Abstract
Drosophila telomeres have been maintained by three families of active transposable elements (TEs), HeT-A, TAHRE, and TART, collectively referred to as HTTs, for tens of millions of years, which contrasts with an unusually high degree of HTT interspecific variation. While the impacts of conflict and domestication are often invoked to explain HTT variation, the telomeres are unstable structures such that neutral mutational processes and evolutionary tradeoffs may also drive HTT evolution. We leveraged population genomic data to analyze nearly 10,000 HTT insertions in 85 Drosophila melanogaster genomes and compared their variation to other more typical TE families. We observe that occasional large-scale copy number expansions of both HTTs and other TE families occur, highlighting that the HTTs are, like their feral cousins, typically repressed but primed to take over given the opportunity. However, large expansions of HTTs are not caused by the runaway activity of any particular HTT subfamilies or even associated with telomere-specific TE activity, as might be expected if HTTs are in strong genetic conflict with their hosts. Rather than conflict, we instead suggest that distinctive aspects of HTT copy number variation and sequence diversity largely reflect telomere instability, with HTT insertions being lost at much higher rates than other TEs elsewhere in the genome. We extend previous observations that telomere deletions occur at a high rate, and surprisingly discover that more than one-third do not appear to have been healed with an HTT insertion. We also report that some HTT families may be preferentially activated by the erosion of whole telomeres, implying the existence of HTT-specific host control mechanisms. We further suggest that the persistent telomere localization of HTTs may reflect a highly successful evolutionary strategy that trades away a stable insertion site in order to have reduced impact on the host genome. We propose that HTT evolution is driven by multiple processes, with niche specialization and telomere instability being previously underappreciated and likely predominant.
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Affiliation(s)
- Michael P McGurk
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Anne-Marie Dion-Côté
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
- Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Daniel A Barbash
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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27
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Kosebent EG, Ozturk S. The spatiotemporal expression of TERT and telomere repeat binding proteins in the postnatal mouse testes. Andrologia 2021; 53:e13976. [PMID: 33544428 DOI: 10.1111/and.13976] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 12/06/2020] [Accepted: 01/01/2021] [Indexed: 12/31/2022] Open
Abstract
Telomeres consist of repetitive DNA sequences and telomere-associated proteins. Telomeres located at the ends of eukaryotic chromosomes undergo shortening due to DNA replication, genotoxic factors and reactive oxygen species. The short telomeres are elongated by the enzyme telomerase expressed in the germ line, embryonic and stem cells. Telomerase is in the structure of ribonucleoprotein composed of telomerase reverse transcriptase (TERT), telomerase RNA component (Terc) and other components. Among telomere-associated proteins, telomeric repeat binding factor 1 (TRF1) and 2 (TRF2) exclusively bind to the double-stranded telomeric DNA to regulate its length. However, protection of telomeres 1 (POT1) interacts with the single-stranded telomeric DNA to protect from DNA damage response. Herein, we characterised the spatial and temporal expression of the TERT, TRF1, TRF2 and POT1 proteins in the postnatal mouse testes at the ages of 6, 8, 16, 20, 29, 32 and 88 days by using immunohistochemistry. Significant differences in the spatiotemporal expression patterns and levels of these proteins were determined in the postnatal testes (p < .05). These findings indicate that TERT and telomere repeat binding proteins seem to be required for maintaining the length and structural integrity of telomeres in the spermatogenic cells from newborn to adult terms.
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Affiliation(s)
- Esra G Kosebent
- Department of Histology and Embryology, Akdeniz University School of Medicine, Antalya, Turkey
| | - Saffet Ozturk
- Department of Histology and Embryology, Akdeniz University School of Medicine, Antalya, Turkey
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28
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Touati R, Tajouri A, Mesaoudi I, Oueslati AE, Lachiri Z, Kharrat M. New methodology for repetitive sequences identification in human X and Y chromosomes. Biomed Signal Process Control 2021; 64:102207. [PMID: 33101452 PMCID: PMC7572123 DOI: 10.1016/j.bspc.2020.102207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 07/23/2020] [Accepted: 09/01/2020] [Indexed: 11/24/2022]
Abstract
Repetitive DNA sequences occupy the major proportion of DNA in the human genome and even in the other species' genomes. The importance of each repetitive DNA type depends on many factors: structural and functional roles, positions, lengths and numbers of these repetitions are clear examples. Conserving such DNA sequences or not in different locations in the chromosome remains a challenge for researchers in biology. Detecting their location despite their great variability and finding novel repetitive sequences remains a challenging task. To side-step this problem, we developed a new method based on signal and image processing tools. In fact, using this method we could find repetitive patterns in DNA images regardless of the repetition length. This new technique seems to be more efficient in detecting new repetitive sequences than bioinformatics tools. In fact, the classical tools present limited performances especially in case of mutations (insertion or deletion). However, modifying one or a few numbers of pixels in the image doesn't affect the global form of the repetitive pattern. As a consequence, we generated a new repetitive patterns database which contains tandem and dispersed repeated sequences. The highly repetitive sequences, we have identified in X and Y chromosomes, are shown to be located in other human chromosomes or in other genomes. The data we have generated is then taken as input to a Convolutional neural network classifier in order to classify them. The system we have constructed is efficient and gives an average of 94.4% as recognition score.
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Affiliation(s)
- Rabeb Touati
- University of Tunis El Manar, LR99ES10 Human Genetics Laboratory, Faculty of Medicine of Tunis (FMT), Tunisia
- University of Tunis El Manar, SITI Laboratory, National School of Engineers of Tunis, BP 37, Le Belvédère, 1002, Tunis, Tunisia
| | - Asma Tajouri
- University of Tunis El Manar, LR99ES10 Human Genetics Laboratory, Faculty of Medicine of Tunis (FMT), Tunisia
| | - Imen Mesaoudi
- University of Tunis El Manar, SITI Laboratory, National School of Engineers of Tunis, BP 37, Le Belvédère, 1002, Tunis, Tunisia
| | - Afef Elloumi Oueslati
- University of Tunis El Manar, SITI Laboratory, National School of Engineers of Tunis, BP 37, Le Belvédère, 1002, Tunis, Tunisia
| | - Zied Lachiri
- University of Tunis El Manar, SITI Laboratory, National School of Engineers of Tunis, BP 37, Le Belvédère, 1002, Tunis, Tunisia
| | - Maher Kharrat
- University of Tunis El Manar, LR99ES10 Human Genetics Laboratory, Faculty of Medicine of Tunis (FMT), Tunisia
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29
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Phage display screening identifies a prostate specific antigen (PSA) -/lo prostate cancer cell specific peptide to retard castration resistance of prostate cancer. Transl Oncol 2021; 14:101020. [PMID: 33508757 PMCID: PMC7844130 DOI: 10.1016/j.tranon.2021.101020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 01/10/2021] [Accepted: 01/12/2021] [Indexed: 01/06/2023] Open
Abstract
To our knowledge, this is the first study to identify a peptide (named as “TAP1”) that specifically binds with PSA−/lo prostate cancer cells. TAP1 inhibited PCa growth both in vitro and in vivo. TAP1 also improved the anti-tumor effect of the anti-androgens and chemotherapeutic agents in vitro. The effects of TAP1 might at least in part by shortening the lengths of telomeres and decreasing the expression of HOXB9 and TGF-β2. Our results indicated that therapeutic peptides that specifically target prostate cancer stem cell might be a very valuable and promising approach to overcome chemoresistance and prevent recurrence in patients with PCa.
Patients with prostate cancer (PCa) will eventually progress to castrate-resistant prostate cancer (CRPC) after androgen deprivation therapy (ADT) treatment. Prostate-specific antigen (PSA)−/lo cells which harbor self-renewing long-term tumor-propagating cells that can be enriched using ALDH+CD44+α2β1+ and can initiate tumor development may represent a critical source of CRPC cells. Our purpose was to find a peptide that specifically targets PSA−/lo PCa cells to retard the development of CRPC. PSA+ and PSA−/lo cells were successfully separated from LNCaP xenograft tumors after prostate- PSAP-GFP vector infection and FACS. A variety of PSA−/lo cells specifically targeting peptide (named as “TAP1” targeted affinity peptide 1) was identified by using phage display library screening. The highest binding rate in TAP1 binding cell subpopulations are identified to be among ALDH+CD44+CXCR4+CD24+ cells. TAP1 significantly inhibited PCa growth both in vitro and in vivo. TAP1 significantly improved the anti-proliferation effect of the anti-androgens (Charcoal dextran-stripped serum (CDSS)+Bicalutamide, Enzalutamide) and chemotherapeutic agents (Abiraterone, Docetaxel, Etoposide) in vitro. TAP1 treatment shortens the length of telomeres in ALDH+CD44+CXCR4+CD24+ cells and significantly reduces the expression of Homeobox B9 (HOXB9) and TGF-β2. In conclusion, PSA−/lo PCa cell-specific targeting peptide (TAP1) that suppressed PCa cell growth both in vitro and in vivo and improved the drug sensitivities of anti-androgens and chemotherapeutic agents at least through shortening the length of telomere and reducing the expression of HOXB9 and TGF-β2. Therapeutic peptides that specifically target prostate cancer stem cell might be a very valuable and promising approach to overcome chemoresistance and prevent recurrence in patients with PCa.
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30
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Červenák F, Sepšiová R, Nosek J, Tomáška Ľ. Step-by-Step Evolution of Telomeres: Lessons from Yeasts. Genome Biol Evol 2020; 13:6127219. [PMID: 33537752 PMCID: PMC7857110 DOI: 10.1093/gbe/evaa268] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2020] [Indexed: 12/23/2022] Open
Abstract
In virtually every eukaryotic species, the ends of nuclear chromosomes are protected by telomeres, nucleoprotein structures counteracting the end-replication problem and suppressing recombination and undue DNA repair. Although in most cases, the primary structure of telomeric DNA is conserved, there are several exceptions to this rule. One is represented by the telomeric repeats of ascomycetous yeasts, which encompass a great variety of sequences, whose evolutionary origin has been puzzling for several decades. At present, the key questions concerning the driving force behind their rapid evolution and the means of co-evolution of telomeric repeats and telomere-binding proteins remain largely unanswered. Previously published studies addressed mostly the general concepts of the evolutionary origin of telomeres, key properties of telomeric proteins as well as the molecular mechanisms of telomere maintenance; however, the evolutionary process itself has not been analyzed thoroughly. Here, we aimed to inspect the evolution of telomeres in ascomycetous yeasts from the subphyla Saccharomycotina and Taphrinomycotina, with special focus on the evolutionary origin of species-specific telomeric repeats. We analyzed the sequences of telomeric repeats from 204 yeast species classified into 20 families and as a result, we propose a step-by-step model, which integrates the diversity of telomeric repeats, telomerase RNAs, telomere-binding protein complexes and explains a propensity of certain species to generate the repeat heterogeneity within a single telomeric array.
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Affiliation(s)
- Filip Červenák
- Department of Genetics, Comenius University in Bratislava, Faculty of Natural Sciences, Bratislava, Slovakia
| | - Regina Sepšiová
- Department of Genetics, Comenius University in Bratislava, Faculty of Natural Sciences, Bratislava, Slovakia
| | - Jozef Nosek
- Department of Biochemistry, Comenius University in Bratislava, Faculty of Natural Sciences, Bratislava, Slovakia
| | - Ľubomír Tomáška
- Department of Genetics, Comenius University in Bratislava, Faculty of Natural Sciences, Bratislava, Slovakia
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31
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Telomeres and telomerase in risk assessment of cardiovascular diseases. Exp Cell Res 2020; 397:112361. [PMID: 33171154 DOI: 10.1016/j.yexcr.2020.112361] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 11/02/2020] [Indexed: 01/14/2023]
Abstract
Telomeres are repetitive nucleoprotein structures located at the ends of chromosomes. Reduction in the number of repetitions causes cell senescence. Cells with high proliferative potential age with each replication cycle. Post-mitotic cells (e.g. cardiovascular cells) have a different aging mechanism. During the aging of cardiovascular system cells, permanent DNA damage occurs in the telomeric regions caused by mitochondrial dysfunction, which is a phenomenon independent of cell proliferation and telomere length. Mitochondrial dysfunction is accompanied by increased production of reactive oxygen species and development of inflammation. This phenomenon in the cells of blood vessels can lead to atherosclerosis development. Telomere damage in cardiomyocytes leads to the activation of the DNA damage response system, histone H2A.X phosphorylation, p53 activation and p21 and p16 protein synthesis, resulting in the SASP phenotype (senescence-associated secretory phenotype), increased inflammation and cardiac dysfunction. Cardiovascular cells show the activity of the TERT subunit of telomerase, an enzyme that prevents telomere shortening. It turns out that disrupting the activity of this enzyme can also contribute to the formation of cardiovascular diseases. Measurements of telomere length according to the "blood-muscle" model may help in the future to assess the risk of cardiovascular complications in people undergoing cardiological procedures, as well as to assess the effectiveness of some drugs.
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32
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Diala I, Shiohama Y, Fujita T, Kotake Y, Demonacos C, Krstic-Demonacos M, Leva GD, Fujii M. Telomerase inhibition, telomere attrition and proliferation arrest of cancer cells induced by phosphorothioate ASO-NLS conjugates targeting hTERC and siRNAs targeting hTERT. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2020; 39:407-425. [PMID: 32310030 DOI: 10.1080/15257770.2020.1713357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Telomerase activity has been regarded as a critical step in cellular immortalization and carcinogenesis and because of this, regulation of telomerase represents an attractive target for anti-tumor specific therapeutics. Recently, one avenue of cancer research focuses on antisense strategy to target the oncogenes or cancer driver genes, in a sequence specific fashion to down-regulate the expression of the target gene. The protein catalytic subunit, human telomerase reverse transcriptase (hTERT) and the template RNA component (hTERC) are essential for telomerase function, thus theoretically, inhibition of telomerase activity can be achieved by interfering with either the gene expression of hTERT or the hTERC of the telomerase enzymatic complex. The present study showed that phosphorothioate antisense oligonucleotide (sASO)-nuclear localization signal (NLS) peptide conjugates targeting hTERC could inhibit telomerase activity very efficiently at 5 μM concentration but less efficiently at 1 μM concentration. On the other hand, siRNA targeting hTERT mRNA could strongly suppress hTERT expression at 200 nM concentration. It was also revealed that siRNA targeting hTERT could induce telomere attrition and then irreversible arrest of proliferation of cancer cells.
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Affiliation(s)
- Irmina Diala
- Department of Biological & Environmental Chemistry, Faculty of Humanity Oriented Science and Engineering, Kindai University, Iizuka, Japan
| | - Yasuo Shiohama
- Department of Biological & Environmental Chemistry, Faculty of Humanity Oriented Science and Engineering, Kindai University, Iizuka, Japan
| | - Takashi Fujita
- Department of Biological & Environmental Chemistry, Faculty of Humanity Oriented Science and Engineering, Kindai University, Iizuka, Japan
| | - Yojiro Kotake
- Department of Biological & Environmental Chemistry, Faculty of Humanity Oriented Science and Engineering, Kindai University, Iizuka, Japan
| | - Constantinos Demonacos
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health Sciences, University of Manchester, Manchester, UK
| | - Marija Krstic-Demonacos
- College of Science & Technology, School of Environment & Life Sciences, University of Salford, Salford, UK
| | - Gianpiero Di Leva
- College of Science & Technology, School of Environment & Life Sciences, University of Salford, Salford, UK
| | - Masayuki Fujii
- Department of Biological & Environmental Chemistry, Faculty of Humanity Oriented Science and Engineering, Kindai University, Iizuka, Japan
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33
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Pańczyszyn A, Boniewska-Bernacka E, Goc A. The role of telomeres and telomerase in the senescence of postmitotic cells. DNA Repair (Amst) 2020; 95:102956. [PMID: 32937289 DOI: 10.1016/j.dnarep.2020.102956] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 08/18/2020] [Indexed: 12/13/2022]
Abstract
Senescence is a process related to the stopping of divisions and changes leading the cell to the SASP phenotype. Permanent senescence of many SASP cells contributes to faster aging of the body and development of age-related diseases due to the release of pro-inflammatory factors. Both mitotically active and non-dividing cells can undergo senescence as a result of activation of different molecular pathways. Telomeres, referred to as the molecular clock, direct the dividing cell into the aging pathway when reaching a critical length. In turn, the senescence of postmitotic cells depends not on the length of telomeres, but their functionality. Dysfunctional telomeres are responsible for triggering the signaling of DNA damage response (DDR). Telomerase subunits in post-mitotic cells translocate between the nucleus, cytoplasm and mitochondria, participating in the regulation of their activity. Among other things, they contribute to the reduction of reactive oxygen species generation, which leads to telomere dysfunction and, consequently, senescence. Some proteins of the shelterin complex also play a protective role by inhibiting senescence-initiating kinases and limiting ROS production by mitochondria.
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Affiliation(s)
- Anna Pańczyszyn
- University of Opole, Institute of Medical Sciences, Department of Biology and Genetics, Opole 45-040, Pl.Kopernika 11a, Poland.
| | - Ewa Boniewska-Bernacka
- University of Opole, Institute of Medical Sciences, Department of Biology and Genetics, Opole 45-040, Pl.Kopernika 11a, Poland.
| | - Anna Goc
- University of Opole, Institute of Medical Sciences, Department of Biology and Genetics, Opole 45-040, Pl.Kopernika 11a, Poland.
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34
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Structural insights into telomere protection and homeostasis regulation by yeast CST complex. Nat Struct Mol Biol 2020; 27:752-762. [PMID: 32661422 DOI: 10.1038/s41594-020-0459-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 05/22/2020] [Indexed: 01/29/2023]
Abstract
Budding yeast Cdc13-Stn1-Ten1 (CST) complex plays an essential role in telomere protection and maintenance. Despite extensive studies, only structural information of individual domains of CST is available; the architecture of CST still remains unclear. Here, we report crystal structures of Kluyveromyces lactis Cdc13-telomeric-DNA, Cdc13-Stn1 and Stn1-Ten1 complexes and propose an integrated model depicting how CST assembles and plays its roles at telomeres. Surprisingly, two oligonucleotide/oligosaccharide-binding (OB) folds of Cdc13 (OB2 and OB4), previously believed to mediate Cdc13 homodimerization, actually form a stable intramolecular interaction. This OB2-OB4 module of Cdc13 is required for the Cdc13-Stn1 interaction that assembles CST into an architecture with a central ring-like core and multiple peripheral modules in a 2:2:2 stoichiometry. Functional analyses indicate that this unique CST architecture is essential for both telomere capping and homeostasis regulation. Overall, our results provide fundamentally valuable structural information regarding the CST complex and its roles in telomere biology.
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35
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The nuts and bolts of animal emotion. Neurosci Biobehav Rev 2020; 113:273-286. [DOI: 10.1016/j.neubiorev.2020.01.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 10/28/2019] [Accepted: 01/22/2020] [Indexed: 02/07/2023]
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36
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Trybek T, Kowalik A, Góźdź S, Kowalska A. Telomeres and telomerase in oncogenesis. Oncol Lett 2020; 20:1015-1027. [PMID: 32724340 PMCID: PMC7377093 DOI: 10.3892/ol.2020.11659] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 03/25/2020] [Indexed: 12/24/2022] Open
Abstract
Telomeres are located at the ends of chromosomes and protect them from degradation. Suppressing the activity of telomerase, a telomere-synthesizing enzyme, and maintaining short telomeres is a protective mechanism against cancer in humans. In most human somatic cells, the expression of telomerase reverse transcriptase (TERT) is repressed and telomerase activity is inhibited. This leads to the progressive shortening of telomeres and inhibition of cell growth in a process called replicative senescence. Most types of primary cancer exhibit telomerase activation, which allows uncontrolled cell proliferation. Previous research indicates that TERT activation also affects cancer development through activities other than the canonical function of mediating telomere elongation. Recent studies have improved the understanding of the structure and function of telomeres and telomerase as well as key mechanisms underlying the activation of TERT and its role in oncogenesis. These advances led to a search for drugs that inhibit telomerase as a target for cancer therapy. The present review article summarizes the organization and function of telomeres, their role in carcinogenesis, and advances in telomerase-targeted therapy.
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Affiliation(s)
- Tomasz Trybek
- Endocrinology Clinic, Holycross Cancer Center, 25-734 Kielce, Poland
| | - Artur Kowalik
- Department of Molecular Diagnostics, Holycross Cancer Center, 25-734 Kielce, Poland
| | - Stanisław Góźdź
- The Faculty of Health Sciences, Jan Kochanowski University, 25-319 Kielce, Poland.,Oncology Clinic, Holycross Cancer Center, 25-734 Kielce, Poland
| | - Aldona Kowalska
- Endocrinology Clinic, Holycross Cancer Center, 25-734 Kielce, Poland.,The Faculty of Health Sciences, Jan Kochanowski University, 25-319 Kielce, Poland
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37
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Abstract
Effective maintenance and stability of our genomes is essential for normal cell division, tissue homeostasis, and cellular and organismal fitness. The processes of chromosome replication and segregation require continual surveillance to insure fidelity. Accurate and efficient repair of DNA damage preserves genome integrity, which if lost can lead to multiple diseases, including cancer. Poly(ADP-ribose) a dynamic and reversible posttranslational modification and the enzymes that catalyze it (PARP1, PARP2, tankyrase 1, and tankyrase 2) function to maintain genome stability through diverse mechanisms. Here we review the role of these enzymes and the modification in genome repair, replication, and resolution in human cells.
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Affiliation(s)
- Kameron Azarm
- Department of Pathology, Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, New York 10016, USA
| | - Susan Smith
- Department of Pathology, Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, New York 10016, USA
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38
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Shukla R, Oh H, Sibille E. Molecular and Cellular Evidence for Age by Disease Interactions: Updates and Path Forward. Am J Geriatr Psychiatry 2020; 28:237-247. [PMID: 31285153 DOI: 10.1016/j.jagp.2019.06.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 05/14/2019] [Accepted: 06/01/2019] [Indexed: 12/31/2022]
Abstract
Characterization of age-associated gene expression changes shows that the brain engages a specific set of genes and biologic pathways along a continuous life-long trajectory and that these genes and pathways overlap with those associated with brain-related disorders. Based on this correlative observation, we have suggested a model of age-by-disease interaction by which brain ageing promotes biologic changes associated with diseases and where deviations from expected age-related trajectories, due to biologic and environmental factors, contribute to defining disease risk or resiliency. In this review, we first evaluate various biomarkers that can be used to study age-by-disease interactions and then focus on transcriptome analysis (i.e., the set of all expressed genes) as a useful tool to explore this interaction. Using the specific example of brain-derived neurotrophic factor and brain-derived neurotrophic factor-associated genes, we then describe molecular events and mechanisms potentially contributing to age-by-disease interactions. Finally, we suggest that long-term biologic adaptations within distinct cellular components of cortical microcircuits, as determined by transcriptome analysis, may integrate and mediate the effects of ageing and diseases. Moving forward, we suggest that analysis of transcriptome similarities between ageing and small molecule-induced system perturbations may lead to novel therapeutics discovery.
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Affiliation(s)
- Rammohan Shukla
- Campbell Family Mental Health Research Institute of CAMH, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Hyunjung Oh
- Campbell Family Mental Health Research Institute of CAMH, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute of CAMH, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada.
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39
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The nuclear pore complex prevents sister chromatid recombination during replicative senescence. Nat Commun 2020; 11:160. [PMID: 31919430 PMCID: PMC6952416 DOI: 10.1038/s41467-019-13979-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 12/10/2019] [Indexed: 12/15/2022] Open
Abstract
The Nuclear Pore Complex (NPC) has emerged as an important hub for processing various types of DNA damage. Here, we uncover that fusing a DNA binding domain to the NPC basket protein Nup1 reduces telomere relocalization to nuclear pores early after telomerase inactivation. This Nup1 modification also impairs the relocalization to the NPC of expanded CAG/CTG triplet repeats. Strikingly, telomerase negative cells bypass senescence when expressing this Nup1 modification by maintaining a minimal telomere length compatible with proliferation through rampant unequal exchanges between sister chromatids. We further report that a Nup1 mutant lacking 36 C-terminal residues recapitulates the phenotypes of the Nup1-LexA fusion indicating a direct role of Nup1 in the relocation of stalled forks to NPCs and restriction of error-prone recombination between repeated sequences. Our results reveal a new mode of telomere maintenance that could shed light on how 20% of cancer cells are maintained without telomerase or ALT. The Nuclear Pore Complex has been linked to DNA damage processing. Here the authors reveal that the Nup1 C-terminus is critical for the relocalization of eroded telomeres to nuclear pores and that modification of Nup1 promotes sister chromatid recombination and unleashes a new telomere maintenance mechanism.
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40
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Luo M, Teng X, Wang B, Zhang J, Liu Y, Liu D, Li H, Lu H. Protection of telomeres 1 (POT1) of Pinus tabuliformis bound the telomere ssDNA. TREE PHYSIOLOGY 2020; 40:119-127. [PMID: 31860719 DOI: 10.1093/treephys/tpz125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 10/14/2019] [Accepted: 11/15/2019] [Indexed: 06/10/2023]
Abstract
Protection of telomeres 1 (POT1) is a telomeric protein that binds to the telomere single-stranded (ss) region. It plays an essential role in maintaining genomic stability in both plants and animals. In this study, we investigated the properties of POT1 in Pinus tabuliformis Carr. (PtPOT1) through electrophoretic mobility shift assay. PtPOT1 harbored affinity for telomeric ssDNA and could bind plant- and mammalian-type ssDNA sequences. Notably, there were two oligonucleotide/oligosaccharide binding (OB) folds, and OB1 or OB2 alone, or both together, could bind ssDNA, which is significantly different from human POT1. Based on our data, we hypothesized that the two OB folds of PtPOT1 bound the same ssDNA. This model not only provides new insight into the ssDNA binding of PtPOT1 but also sheds light on the functional divergence of POT1 proteins in gymnosperms and humans.
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Affiliation(s)
- Mei Luo
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, No.35, Qinghua East road, Haidian District, Beijing 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Xiaotong Teng
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Bing Wang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Jiaxue Zhang
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Yadi Liu
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Di Liu
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Hui Li
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Hai Lu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, No.35, Qinghua East road, Haidian District, Beijing 100083, China
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
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41
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Zhang M, Wang B, Li T, Liu R, Xiao Y, Geng X, Li G, Liu Q, Price CM, Liu Y, Wang F. Mammalian CST averts replication failure by preventing G-quadruplex accumulation. Nucleic Acids Res 2019; 47:5243-5259. [PMID: 30976812 PMCID: PMC6547417 DOI: 10.1093/nar/gkz264] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 03/28/2019] [Accepted: 04/03/2019] [Indexed: 11/12/2022] Open
Abstract
Human CST (CTC1-STN1-TEN1) is an RPA-like complex that associates with G-rich single-strand DNA and helps resolve replication problems both at telomeres and genome-wide. We previously showed that CST binds and disrupts G-quadruplex (G4) DNA in vitro, suggesting that CST may prevent in vivo blocks to replication by resolving G4 structures. Here, we demonstrate that CST binds and unfolds G4 with similar efficiency to RPA. In cells, CST is recruited to telomeric and non-telomeric chromatin upon G4 stabilization, even when ATR/ATM pathways were inhibited. STN1 depletion increases G4 accumulation and slows bulk genomic DNA replication. At telomeres, combined STN1 depletion and G4 stabilization causes multi-telomere FISH signals and telomere loss, hallmarks of deficient telomere duplex replication. Strand-specific telomere FISH indicates preferential loss of C-strand DNA while analysis of BrdU uptake during leading and lagging-strand telomere replication shows preferential under-replication of lagging telomeres. Together these results indicate a block to Okazaki fragment synthesis. Overall, our findings indicate a novel role for CST in maintaining genome integrity through resolution of G4 structures both ahead of the replication fork and on the lagging strand template.
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Affiliation(s)
- Miaomiao Zhang
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
| | - Bing Wang
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
| | - Tingfang Li
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
| | - Rui Liu
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
| | - Yingnan Xiao
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
| | - Xin Geng
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
| | - Guang Li
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
| | - Qiang Liu
- Department of Radiobiology, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College,Tianjin 300192, PR China
| | - Carolyn M Price
- Departments of Cancer and Cell Biology, University of Cincinnati, Cincinnati, OH, USA
| | - Yang Liu
- Department of Radiobiology, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College,Tianjin 300192, PR China
| | - Feng Wang
- Department of Genetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, PR China
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Combined treatment with emodin and a telomerase inhibitor induces significant telomere damage/dysfunction and cell death. Cell Death Dis 2019; 10:527. [PMID: 31296842 PMCID: PMC6624283 DOI: 10.1038/s41419-019-1768-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 06/23/2019] [Accepted: 06/24/2019] [Indexed: 01/06/2023]
Abstract
G-quadruplex telomeric secondary structures represent natural replication fork barriers and must be resolved to permit efficient replication. Stabilization of telomeric G4 leads to telomere dysfunctions demonstrated by telomere shortening or damage, resulting in genome instability and apoptosis. Chemical compounds targeting G4 structures have been reported to induce telomere disturbance and tumor suppression. Here, virtual screening was performed in a natural compound library using PyRx to identify novel G4 ligands. Emodin was identified as one of the best candidates, showing a great G4-binding potential. Subsequently, we confirmed that emodin could stabilize G4 structures in vitro and trigger telomere dysfunctions including fragile telomeres, telomere loss, and telomeric DNA damage. However, this telomere disturbance could be rescued by subsequent elevation of telomerase activity; in contrast, when we treated the cells with the telomerase inhibitor BIBR1532 upon emodin treatment, permanent telomere disturbance and obvious growth inhibition of 4T1-cell xenograft tumors were observed in mice. Taken together, our results show for the first time that emodin-induced telomeric DNA damage can upregulate telomerase activity, which may weaken its anticancer effect. The combined use of emodin and the telomerase inhibitor synergistically induced telomere dysfunction and inhibited tumor generation.
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43
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Monroy-Jaramillo N, Dyukova E, Walss-Bass C. Telomere length in psychiatric disorders: Is it more than an ageing marker? World J Biol Psychiatry 2019; 19:S2-S20. [PMID: 28000540 DOI: 10.1080/15622975.2016.1273550] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVES Psychiatric and substance-use disorders have been associated with premature biological ageing. Telomere length (TL), considered an ageing marker, has been analysed in psychiatric disorders, and to a lesser extent in substance-use disorders, with recent findings suggesting TL may be related to disease pathology. METHODS We conducted a critical and non-systematic literature search of TL studies published up to June 2016 in psychiatric and substance-use disorders, focussing on studies describing mechanisms, including studies linking telomere biology with genetic factors, stress and mitochondrial alterations (104 studies selected). RESULTS Patients with major depressive disorder and anxiety appear to have shorter leukocyte telomeres compared to controls. Inconclusive results are found for other psychiatric disorders and for substance-use disorders. This may be due in part to differences in medication treatment and response, as studies suggest that some psychotropic medications may modulate TL. Importantly, some studies establish a relationship between telomere machinery, stress and mitochondria function in psychiatric and substance-use disorders. CONCLUSIONS While further longitudinal studies considering telomere genetics are needed to clarify the cause-effect link between telomeres and mitochondria function in psychiatric and substance-use disorders, the recent findings linking these biological processes suggest that telomeres may be more than ageing markers.
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Affiliation(s)
- Nancy Monroy-Jaramillo
- a Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences , McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth) , Houston , TX , USA.,b Department of Genetics , National Institute of Neurology and Neurosurgery, Manuel Velasco Suarez , Mexico City , Mexico
| | - Elena Dyukova
- a Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences , McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth) , Houston , TX , USA
| | - Consuelo Walss-Bass
- a Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences , McGovern Medical School, University of Texas Health Science Center at Houston (UTHealth) , Houston , TX , USA
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44
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Hiskens MI, Angoa-Pérez M, Schneiders AG, Vella RK, Fenning AS. Modeling sports-related mild traumatic brain injury in animals-A systematic review. J Neurosci Res 2019; 97:1194-1222. [PMID: 31135069 DOI: 10.1002/jnr.24472] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/22/2019] [Accepted: 05/07/2019] [Indexed: 12/14/2022]
Abstract
Sports-related head trauma has emerged as an important public health issue, as mild traumatic brain injuries (mTBIs) may result in neurodegenerative disorders such as chronic traumatic encephalopathy (CTE). Research into mTBI and CTE pathophysiology are difficult to undertake in athletes, with observational trials and post-mortem analysis the current mainstays. Thus, animal models play an important role in the study of mTBI, however, traditional animal models have focused on acute, severe injuries rather than the more typical mTBI's seen in sport injuries. Recently, a number of animal models have been developed that are both appropriately scaled and biomechanically relevant to the forces sustained by athletes. This review aimed to examine the literature for variables included in these animal models, and the resulting neurotrauma as evidenced by pathology and behavioral deficits. A systematic search of the literature was performed in multiple electronic databases. The inclusion criteria required mimicry of athlete mTBI conditions: freedom of head movement, lack of surgical alteration of the skull, and application of direct contact force. Studies were analyzed for variables including apparatus design features (impact force, change in animal head velocity, and kinetic energy transfer to the head), demonstrated pathology (phosphorylated tau, TDP-43 aggregation, diffuse axonal injury, gliosis, cytokine inflammation response, and genetic integrity), and behavioral changes. These studies suggested that appropriate animal models can assist in understanding the pathological and functional outcomes of athlete mTBI, and could be used as a platform for future studies of diagnostic/prognostic markers and in the development of treatment interventions.
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Affiliation(s)
- Matthew I Hiskens
- School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
| | - Mariana Angoa-Pérez
- Research & Development Service, John D. Dingell VA Medical Center, Detroit, Michigan.,Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, Michigan
| | - Anthony G Schneiders
- School of Health, Medical and Applied Sciences, Central Queensland University, Branyan, Australia
| | - Rebecca K Vella
- School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
| | - Andrew S Fenning
- School of Health, Medical and Applied Sciences, Central Queensland University, Rockhampton, Australia
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45
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González-Giraldo Y, Forero DA, Echeverria V, Garcia-Segura LM, Barreto GE. Tibolone attenuates inflammatory response by palmitic acid and preserves mitochondrial membrane potential in astrocytic cells through estrogen receptor beta. Mol Cell Endocrinol 2019; 486:65-78. [PMID: 30822454 DOI: 10.1016/j.mce.2019.02.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/17/2019] [Accepted: 02/18/2019] [Indexed: 12/19/2022]
Abstract
Palmitic acid (PA) induces several metabolic and molecular changes in astrocytes, and, it is involved in pathological conditions related to neurodegenerative diseases. Previously, we demonstrated that tibolone, a synthetic steroid with estrogenic, progestogenic and androgenic actions, protects cells from mitochondrial damage and morphological changes induced by PA. Here, we have evaluated which estrogen receptor is involved in protective actions of tibolone and analyzed whether tibolone reverses gene expression changes induced by PA. Tibolone actions on astrocytic cells were mimicked by agonists of estrogen receptor α (ERα) and β (ERβ), but the blockade of both ERs suggested a predominance of ERβ on mitochondria membrane potential. Expression analysis showed a significant effect of tibolone on genes associated with inflammation such as IL6, IL1B and miR155-3p. It is noteworthy that tibolone attenuated the increased expression of TERT, TERC and DNMT3B genes induced by palmitic acid. Our results suggest that tibolone has anti-inflammatory effects and can modulate pathways associated with DNA methylation and telomeric complex. However, future studies are needed to elucidate the role of epigenetic mechanisms and telomere-associated proteins on tibolone actions.
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Affiliation(s)
- Yeimy González-Giraldo
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C, Colombia
| | - Diego A Forero
- Laboratory of Neuropsychiatric Genetics, Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | - Valentina Echeverria
- Facultad de Ciencias de la Salud, Universidad San Sebastian, Lientur 1457, 4080871, Concepción, Chile; Research & Development Service, Bay Pines VA Healthcare System, Bay Pines, FL, 33744, USA
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), 28002, Madrid, Spain; Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C, Colombia.
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46
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Anitha A, Thanseem I, Vasu MM, Viswambharan V, Poovathinal SA. Telomeres in neurological disorders. Adv Clin Chem 2019; 90:81-132. [PMID: 31122612 DOI: 10.1016/bs.acc.2019.01.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ever since their discovery, the telomeres and the telomerase have been topics of intensive research, first as a mechanism of cellular aging and later as an indicator of health and diseases in humans. By protecting the chromosome ends, the telomeres play a vital role in preserving the information in our genome. Telomeres shorten with age and the rate of telomere erosion provides insight into the proliferation history of cells. The pace of telomere attrition is known to increase at the onset of several pathological conditions. Telomere shortening has been emerging as a potential contributor in the pathogenesis of several neurological disorders including autism spectrum disorders (ASD), schizophrenia, Alzheimer's disease (AD), Parkinson's disease (PD) and depression. The rate of telomere attrition in the brain is slower than that of other tissues owing to the low rate of cell proliferation in brain. Telomere maintenance is crucial for the functioning of stem cells in brain. Taking together the studies on telomere attrition in various neurological disorders, an association between telomere shortening and disease status has been demonstrated in schizophrenia, AD and depression, in spite of a few negative reports. But, studies in ASD and PD have failed to produce conclusive results. The cause-effect relationship between TL and neurological disorders is yet to be elucidated. The factors responsible for telomere erosion, which have also been implicated in the pathogenesis of neurological disorders, need to be explored in detail. Telomerase activation is now being considered as a potential therapeutic strategy for neurological disorders.
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Affiliation(s)
- Ayyappan Anitha
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India.
| | - Ismail Thanseem
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Mahesh Mundalil Vasu
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Vijitha Viswambharan
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Suresh A Poovathinal
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
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47
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Harrington L, Pucci F. In medio stat virtus: unanticipated consequences of telomere dysequilibrium. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2016.0444. [PMID: 29335368 PMCID: PMC5784064 DOI: 10.1098/rstb.2016.0444] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2017] [Indexed: 12/13/2022] Open
Abstract
The integrity of chromosome ends, or telomeres, depends on myriad processes that must balance the need to compact and protect the telomeric, G-rich DNA from detection as a double-stranded DNA break, and yet still permit access to enzymes that process, replicate and maintain a sufficient reserve of telomeric DNA. When unable to maintain this equilibrium, erosion of telomeres leads to perturbations at or near the telomeres themselves, including loss of binding by the telomere protective complex, shelterin, and alterations in transcription and post-translational modifications of histones. Although the catastrophic consequences of full telomere de-protection are well described, recent evidence points to other, less obvious perturbations that arise when telomere length equilibrium is altered. For example, critically short telomeres also perturb DNA methylation and histone post-translational modifications at distal sites throughout the genome. In murine stem cells for example, this dysregulated chromatin leads to inappropriate suppression of pluripotency regulator factors such as Nanog. This review summarizes these recent findings, with an emphasis on how these genome-wide, telomere-induced perturbations can have profound consequences on cell function and fate. This article is part of the theme issue ‘Understanding diversity in telomere dynamics’.
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Affiliation(s)
- Lea Harrington
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, College of Science and Engineering, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JR, UK
| | - Fabio Pucci
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, College of Science and Engineering, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JR, UK
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48
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Powell TR, De Jong S, Breen G, Lewis CM, Dima D. Telomere length as a predictor of emotional processing in the brain. Hum Brain Mapp 2018; 40:1750-1759. [PMID: 30511786 PMCID: PMC6492163 DOI: 10.1002/hbm.24487] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/20/2018] [Accepted: 11/24/2018] [Indexed: 12/24/2022] Open
Abstract
Shorter telomere length (TL) has been associated with the development of mood disorders as well as abnormalities in brain morphology. However, so far, no studies have considered the role TL may have on brain function during tasks relevant to mood disorders. In this study, we examine the relationship between TL and functional brain activation and connectivity, while participants (n = 112) perform a functional magnetic resonance imaging (fMRI) facial affect recognition task. Additionally, because variation in TL has a substantial genetic component we calculated polygenic risk scores for TL to test if they predict face‐related functional brain activation. First, our results showed that TL was positively associated with increased activation in the amygdala and cuneus, as well as increased connectivity from posterior regions of the face network to the ventral prefrontal cortex. Second, polygenic risk scores for TL show a positive association with medial prefrontal cortex activation. The data support the view that TL and genetic loading for shorter telomeres, influence the function of brain regions known to be involved in emotional processing.
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Affiliation(s)
- Timothy R Powell
- Social, Genetic and Developmental Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Simone De Jong
- Social, Genetic and Developmental Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,National Institute for Health Research Biomedical Research Centre for Mental Health, Institute of Psychiatry, Psychology and Neuroscience at the Maudsley Hospital and King's College London, London, United Kingdom
| | - Gerome Breen
- Social, Genetic and Developmental Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,National Institute for Health Research Biomedical Research Centre for Mental Health, Institute of Psychiatry, Psychology and Neuroscience at the Maudsley Hospital and King's College London, London, United Kingdom
| | - Cathryn M Lewis
- Social, Genetic and Developmental Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,National Institute for Health Research Biomedical Research Centre for Mental Health, Institute of Psychiatry, Psychology and Neuroscience at the Maudsley Hospital and King's College London, London, United Kingdom.,Department of Medical and Molecular Genetics, Guy's Hospital, King's College London, London, United Kingdom
| | - Danai Dima
- Department of Psychology, School of Arts and Social Sciences, City, University of London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
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49
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Polito F, Cucinotta M, Abbritti RV, Brogna A, Pergolizzi S, Tomasello C, Barresi V, Angileri FF, Di Giorgio R, Conti A, La Torre D, Germanò A, Aguennouz M. Silencing of telomere-binding protein adrenocortical dysplasia (ACD) homolog enhances radiosensitivity in glioblastoma cells. Transl Res 2018; 202:99-108. [PMID: 30080989 DOI: 10.1016/j.trsl.2018.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 06/23/2018] [Accepted: 07/10/2018] [Indexed: 11/30/2022]
Abstract
Adrenocortical dysplasia (ACD) is a shelterin protein involved in the maintenance of telomere length and in cancer radioresistance. This study investigated the expression profile of ACD in human gliomas and its role in radioresistance of glioma cells. The expression of ACD was analyzed in 62 different grades of glioma tissues and correlated with prognosis. A radioresistant cell line was generated from U87MG cells. For mechanistic studies, ACD was inhibited by small interfering RNA-targeting ACD and the effect on cell radioresistance, telomerase activity, cyclinD1, caspase-3, hTERT, and BIRC1 was evaluated. Clonogenic assay was performed after irradiation, to investigate the effect of ACD silencing on radiation sensitivity. ACD expression appeared strongly upregulated in higher grade gliomas, and its expression was significantly correlated to grading and poor prognosis. In glioma cell lines, ACD expression pattern was similar to those observed in glioma tissues. In irradiated cells, ACD expression was increased in an ionizing radiation dose-dependent manner. A higher expression of ACD was observed in the radioresistant clones than parental cells. Silencing of ACD led to the enhanced radiation sensitivity, decreased telomerase activity and cyclin D1 expression, reduced expression of BIRC1, and finally to the upregulation of caspase-3. This study represents the first report, which demonstrated the expression pattern of ACD in gliomas and its prognostic value. Our results suggested that ACD is involved in glioblastoma radioresistance, likely through the modulation of telomerase activity, proliferation, and apoptosis. ACD might represent a potential molecular biomarker and a novel therapeutic target in glioblastoma.
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Affiliation(s)
- Francesca Polito
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | - Maria Cucinotta
- Department of Clinical and Experimental Medicine, University of Messina, Italy
| | - Rosaria V Abbritti
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | - Anna Brogna
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | - Stefano Pergolizzi
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | - Chiara Tomasello
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | | | - Flavio F Angileri
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | | | - Alfredo Conti
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | - Domenico La Torre
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | - Antonino Germanò
- Department of Biomedical, Dental Sciences and of Morphological and Functional Images, University of Messina, Italy
| | - M'hammed Aguennouz
- Department of Clinical and Experimental Medicine, University of Messina, Italy.
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He L, Chen Z, Dai B, Li G, Zhu G. Low-level lead exposure and cardiovascular disease: the roles of telomere shortening and lipid disturbance. J Toxicol Sci 2018; 43:623-630. [PMID: 30404996 DOI: 10.2131/jts.43.623] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Lead exposure contributing to cardiovascular diseases is known and recognized widely. As the deleterious effects of low lead exposure attained increasing attention over the last decades, there have been numerous studies exploring the association of low levels of lead exposure and cardiovascular diseases. Moreover, it has been observed that lead exposure could cause telomere shortening and lipid disturbance, and that telomere shortening and lipid disturbance are closely related with cardiovascular diseases. Hence, telomere shortening and lipid disturbance might play an important role in the pathophysiological process of chronic low levels of lead exposure contributing to cardiovascular diseases. This review is intended to explore views of the rarely mentioned mechanism, telomere shortening and lipid disturbance, and the cardiovascular effects of low levels of lead exposure.
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Affiliation(s)
- Liyun He
- The First Clinical Medical College of Nanchang University, China
| | - Zhenying Chen
- The Fourth Clinical Medical College of Nanchang University, China
| | - Bo Dai
- The Fourth Clinical Medical College of Nanchang University, China
| | - Guilin Li
- Department of Physiology, Medical College of Nanchang University, China
| | - Gaochun Zhu
- Department of Anatomy, Medical College of Nanchang University, China
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