Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 1.541
Filter
1.
Transfus Med Hemother ; 51(5): 292-309, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39371255

ABSTRACT

Background: Telomeres are the end-capping structures of all eukaryotic chromosomes thereby protecting the genome from damage and degradation. During the aging process, telomeres shorten continuously with each cell division until critically short telomeres prevent further proliferation whereby cells undergo terminal differentiation, senescence, or apoptosis. Premature aging due to critically short telomere length (TL) can also result from pathogenic germline variants in the telomerase complex or related genes that typically counteract replicative telomere shortening in germline and certain somatic cell populations, e.g., hematopoetic stem cells. Inherited diseases that result in altered telomere maintenance are summarized under the term telomere biology disorder (TBD). Summary: Since TL both reflects but more importantly restricts the replicative capacity of various human tissues, a sufficient telomere reserve is particularly important in cells with high proliferative activity (e.g., hematopoiesis, immune cells, intestinal cells, liver, lung, and skin). Consequently, altered telomere maintenance as observed in TBDs typically results in premature replicative cellular exhaustion in the respective organ systems eventually leading to life-threatening complications such as bone marrow failure (BMF), pulmonary fibrosis, and liver cirrhosis. Key Messages: The recognition of a potential congenital origin in approximately 10% of adult patients with clinical BMF is of utmost importance for the proper diagnosis, appropriate patient and family counseling, to prevent the use of inefficient treatment and to avoid therapy-related toxicities including appropriate donor selection when patients have to undergo stem cell transplantation from related donors. This review summarizes the current state of knowledge about TBDs with particular focus on the clinical manifestation patterns in children (termed early onset TBD) compared to adults (late-onset TBD) including typical treatment- and disease course-related complications as well as their prognosis and adequate therapy. Thereby, it aims to raise awareness for a disease group that is currently still highly underdiagnosed particularly when it first manifests itself in adulthood.

2.
Genome Biol ; 25(1): 246, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39300486

ABSTRACT

BACKGROUND: N6-methyladenosine (m6A), the most abundant internal modification on eukaryotic mRNA, and N6, 2'-O-dimethyladenosine (m6Am), are epitranscriptomic marks that function in multiple aspects of posttranscriptional regulation. Fat mass and obesity-associated protein (FTO) can remove both m6A and m6Am; however, little is known about how FTO achieves its substrate selectivity. RESULTS: Here, we demonstrate that ZBTB48, a C2H2-zinc finger protein that functions in telomere maintenance, associates with FTO and binds both mRNA and the telomere-associated regulatory RNA TERRA to regulate the functional interactions of FTO with target transcripts. Specifically, depletion of ZBTB48 affects targeting of FTO to sites of m6A/m6Am modification, changes cellular m6A/m6Am levels and, consequently, alters decay rates of target RNAs. ZBTB48 ablation also accelerates growth of HCT-116 colorectal cancer cells and modulates FTO-dependent regulation of Metastasis-associated protein 1 (MTA1) transcripts by controlling the binding to MTA1 mRNA of the m6A reader IGF2BP2. CONCLUSIONS: Our findings thus uncover a previously unknown mechanism of posttranscriptional regulation in which ZBTB48 co-ordinates RNA-binding of the m6A/m6Am demethylase FTO to control expression of its target RNAs.


Subject(s)
Adenosine , Alpha-Ketoglutarate-Dependent Dioxygenase FTO , Humans , Adenosine/analogs & derivatives , Adenosine/metabolism , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/metabolism , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics , HCT116 Cells , RNA, Messenger/metabolism , RNA, Messenger/genetics , Telomere/metabolism , Telomere/genetics , Transcription Factors/metabolism , Transcription Factors/genetics , Zinc Fingers
3.
J Affect Disord ; 368: 599-606, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39303890

ABSTRACT

BACKGROUND: Although stressor exposure early in life was known risk factor for telomere length (TL) attrition, limited literature explored it across generations. Furthermore, the effects of resilience have rarely been examined. Here, we examined whether the effects of intergenerational parent-child separation on offspring 1-year TL attrition vary by the levels of resilience. METHOD: In a sample of 342 mother-child dyads living in rural China, the intergenerational continuation of parent-child separation was defined as the two generations both experiencing parent-child separation from both parents for >6 months a year early in life assessed by the parent-reported questionnaire, whereas intergenerational discontinuity refers to parent-child separation exposed in one generation only. TL was measured at baseline (from June to November 2021) and 1-year later with children's buccal mucosa swabs, with resilience polygenic risk scores (PRS) evaluated based on 4 single-nucleotide variations in 4 resilience-related genes (OXTR, FKBP5, NPY, and TNF-α). RESULTS: Among 342 mother-offspring dyads, 35 (10.2 %) experienced intergenerational continuation of parent-child separation, and 139 (40.6 %) were identified as discontinuous. Remarkably, a 0.12-point reduction in TL attrition was only associated with intergenerational continuation of parent-child separation (95 % CI: 0.04, 0.21, P < 0.01) but not discontinuity. Importantly, the association between intergenerational continuation of parent-child separation with accelerated TL attrition disappeared in offspring with high resilience PRS (ß = 0.07, 95%CI: -0.06, 0.21). CONCLUSION: Our findings highlight the importance of breaking the intergenerational cycle of parent-child separation and the moderating effects of resilience on TL attrition for children exposed to adversity.

4.
Reprod Sci ; 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39269661

ABSTRACT

Characterization of long non-coding telomeric repeat-containing RNAs in sperm of normozoospermic and oligoasthenozoospermic men as new biomarker of idiopathic male infertility. We conducted an observational prospective study with two groups of men with normal or orligoasthenozoospermic spermiogram, aged 40 and above. Fertility parameters were analyzed in men undergoing intracytoplasmic sperm injection with donor oocytes, to avoid the female factor. Telomeric RNAs and telomere length were measured by quantitative fluorescent in situ hybridization. Data from seminal parameters and in-vitro fertilization were assessed according to IVIRMA protocols. Patients with oligoasthenozoospermia, who had worse seminal parameters, also obtained embryos with lower inner-cell-mass quality (p = 0.04), despite using donor oocytes. While mean levels of telomeric RNAs were similar for both groups, the percentage of spermatozoa with more than 3 foci was higher in oligoasthenozoospermic men (p = 0.02). Regarding telomere length, oligoasthenozoospermic men had shorter mean, a higher accumulation of short telomeres (15th percentile; p = 0.03) and a lower percentage of very-long telomeres (85th percentile; p = 0.01). Finally, a positive correlation was found between telomeric-RNAs intensity and total progressive motility in the spermatozoa of normozoospermic patients (r = 0.5; p = 0.03). Telomeric parameters were altered in the spermatozoa of the oligoasthenozoospermic group, which also showed lower quality embryos. Interestingly, in the normozoospermic group, a correlation was found between progressive motility and telomeric RNA levels, suggesting that they could be a good biomarker of sperm quality. Further studies are required to confirm these results and translate them into the clinical practice.Trial registration number: 1711-MAD-109-CB, 07/07/2021.

5.
Int J Med Sci ; 21(11): 2065-2080, 2024.
Article in English | MEDLINE | ID: mdl-39239547

ABSTRACT

Sarcoma is a rare tumor derived from the mesenchymal tissue and mainly found in children and adolescents. The outcome for patients with sarcoma is relatively poor compared with that for many other solid malignant tumors. Sarcomas have a highly heterogeneous pathogenesis, histopathology and biological behavior. Dysregulated signaling pathways and various gene mutations are frequently observed in sarcomas. The telomere maintenance mechanism (TMM) has recently been considered as a prognostic factor for patients with sarcomas, and alternative lengthening of telomeres (ALT) positivity has been correlated with poor outcomes in patients with several types of sarcomas. Therefore, telomeres and telomerases may be useful targets for treating sarcomas. This review aims to provide an overview of telomere and telomerase biology in sarcomas.


Subject(s)
Sarcoma , Telomerase , Telomere Homeostasis , Telomere , Humans , Telomerase/genetics , Telomerase/metabolism , Sarcoma/genetics , Sarcoma/therapy , Sarcoma/pathology , Telomere/genetics , Telomere/metabolism , Telomere Homeostasis/genetics , Prognosis , Mutation
6.
Front Oncol ; 14: 1399442, 2024.
Article in English | MEDLINE | ID: mdl-39224814

ABSTRACT

Introduction: Alternative lengthening of telomeres (ALT) occurs in sarcomas and ALT cancers share common mechanisms of therapy resistance or sensitivity. Telomeric DNA C-circles are self-primed circular telomeric repeats detected with a PCR assay that provide a sensitive and specific biomarker exclusive to ALT cancers. We have previously shown that 23% of high-risk neuroblastomas are of the ALT phenotype. Here, we investigate the frequency of ALT in Ewing's family sarcoma (EFS), rhabdomyosarcoma (RMS), and osteosarcoma (OS) by analyzing DNA from fresh frozen primary tumor samples utilizing the real-time PCR C-circle Assay (CCA). Methods: We reviewed prior publications on ALT detection in pediatric sarcomas. DNA was extracted from fresh frozen primary tumors, fluorometrically quantified, C-circles were selectively enriched by isothermal rolling cycle amplification and detected by real-time PCR. Results: The sample cohort consisted of DNA from 95 EFS, 191 RMS, and 87 OS primary tumors. One EFS and 4 RMS samples were inevaluable. Using C-circle positive (CC+) cutoffs previously defined for high-risk neuroblastoma, we observed 0 of 94 EFS, 5 of 187 RMS, and 62 of 87 OS CC+ tumors. Conclusions: Utilizing the ALT-specific CCA we observed ALT in 0% of EFS, 2.7% of RMS, and 71% of OS. These data are comparable to prior studies in EFS and OS using less specific ALT markers. The CCA can provide a robust and sensitive means of identifying ALT in sarcomas and has potential as a companion diagnostic for ALT targeted therapeutics.

7.
BMC Med ; 22(1): 359, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39227814

ABSTRACT

BACKGROUND: Psychological and trauma-related factors are associated with many diseases and mortality. However, a comprehensive assessment of the association between psycho-trauma exposures and aging acceleration is currently lacking. METHODS: Using data from 332,359 UK Biobank participants, we calculated biological aging acceleration, indexed by the presence of leukocyte telomere length (LTL) deviation (i.e., the difference between genetically determined and observed LTL > 0). The acceleration of facial aging (i.e., looking older than the chronological age) was assessed using a self-report question. Then, we estimated the associations of each psycho-trauma factor with biological and facial aging acceleration, using logistic regression models adjusted for multiple important covariates. Furthermore, restricted to 99,180 participants with complete psychological and trauma-related data, we identified clusters of individuals with distinct psycho-trauma patterns using the latent class analysis method and assessed their associations with aging acceleration using similar models. RESULTS: We observed most of the studied psycho-trauma factors were associated with biological and facial aging acceleration. Compared to the "Absence of trauma and psychopathology" cluster, the "adverse childhood experiences (ACEs) with psychopathology" cluster showed strong associations with those aging measurements (odds ratio [OR] = 1.13 [1.05 - 1.23] for biological and 1.52 [1.18 - 1.95] for facial aging acceleration), while no such association was observed for the "ACEs without psychopathology" cluster (1.04 [0.99 - 1.09] and 1.02 [0.84 - 1.24]. CONCLUSIONS: Our study demonstrated significant associations of psycho-trauma factors with both biological and facial aging acceleration. The differential aging consequences observed among ACEs exposed individuals with and without psychopathology prompt interventions aimed to improve individuals' psychological resilience to prevent aging acceleration.


Subject(s)
Aging , Humans , United Kingdom/epidemiology , Male , Female , Middle Aged , Aging/physiology , Aged , Biological Specimen Banks , Adult , Face , Leukocytes , Adverse Childhood Experiences , UK Biobank
8.
Hum Immunol ; 85(6): 111146, 2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39317127

ABSTRACT

The function of the immune system is highly dependent on cellular differentiation and clonal expansion of antigen-specific lymphocytes. Telomeres are conserved DNA-protein structures of linear chromosome termini. Telomere length has been investigated to be different in various lymphocyte subpopulations depending on their function and to change with aging. Association of accelerated telomere loss compared to matched controls has already been confirmed in many syndromes with immune dysregulation. Immunodeficiencies connected with dysfunction of telomere termini are dyskeratosis congenita, ICF syndrome (Immunodeficiency, centromeric instability and facial anomalies syndrome) genetic disorders involving DNA repair and disorders involving the VDJ recombination.

9.
Mol Ecol ; : e17491, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39192633

ABSTRACT

Telomere lengths and telomere dynamics can correlate with lifespan, behaviour and individual quality. Such relationships have spurred interest in understanding variation in telomere lengths and their dynamics within and between populations. Many studies have identified how environmental processes can influence telomere dynamics, but the role of genetic variation is much less well characterized. To provide a novel perspective on how telomeric variation relates to genetic variability, we longitudinally sampled individuals across a narrow hybrid zone (n = 127 samples), wherein two Manacus species characterized by contrasting genome-wide heterozygosity interbreed. We measured individual (n = 66) and population (n = 3) differences in genome-wide heterozygosity and, among hybrids, amount of genetic admixture using RADseq-generated SNPs. We tested for population differences in telomere lengths and telomere dynamics. We then examined how telomere lengths and telomere dynamics covaried with genome-wide heterozygosity within populations. Hybrid individuals exhibited longer telomeres, on average, than individuals sampled in the adjacent parental populations. No population differences in telomere dynamics were observed. Within the parental population characterized by relatively low heterozygosity, higher genome-wide heterozygosity was associated with shorter telomeres and higher rates of telomere shortening-a pattern that was less apparent in the other populations. All of these relationships were independent of sex, despite the contrasting life histories of male and female manakins. Our study highlights how population comparisons can reveal interrelationships between genetic variation and telomeres, and how naturally occurring hybridization and genome-wide heterozygosity can relate to telomere lengths and telomere dynamics.

10.
EMBO Mol Med ; 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39198715

ABSTRACT

Dyskeratosis congenita (DC) is a rare inherited bone marrow failure syndrome, caused by genetic mutations that principally affect telomere biology. Approximately 35% of cases remain uncharacterised at the genetic level. To explore the genetic landscape, we conducted genetic studies on a large collection of clinically diagnosed cases of DC as well as cases exhibiting features resembling DC, referred to as 'DC-like' (DCL). This led us to identify several novel pathogenic variants within known genetic loci and in the novel X-linked gene, POLA1. In addition, we have also identified several novel variants in POT1 and ZCCHC8 in multiple cases from different families expanding the allelic series of DC and DCL phenotypes. Functional characterisation of novel POLA1 and POT1 variants, revealed pathogenic effects on protein-protein interactions with primase, CTC1-STN1-TEN1 (CST) and shelterin subunit complexes, that are critical for telomere maintenance. ZCCHC8 variants demonstrated ZCCHC8 deficiency and signs of pervasive transcription, triggering inflammation in patients' blood. In conclusion, our studies expand the current genetic architecture and broaden our understanding of disease mechanisms underlying DC and DCL disorders.

11.
Mol Cell ; 84(16): 3044-3060.e11, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39142279

ABSTRACT

G-quadruplexes (G4s) form throughout the genome and influence important cellular processes. Their deregulation can challenge DNA replication fork progression and threaten genome stability. Here, we demonstrate an unexpected role for the double-stranded DNA (dsDNA) translocase helicase-like transcription factor (HLTF) in responding to G4s. We show that HLTF, which is enriched at G4s in the human genome, can directly unfold G4s in vitro and uses this ATP-dependent translocase function to suppress G4 accumulation throughout the cell cycle. Additionally, MSH2 (a component of MutS heterodimers that bind G4s) and HLTF act synergistically to suppress G4 accumulation, restrict alternative lengthening of telomeres, and promote resistance to G4-stabilizing drugs. In a discrete but complementary role, HLTF restrains DNA synthesis when G4s are stabilized by suppressing primase-polymerase (PrimPol)-dependent repriming. Together, the distinct roles of HLTF in the G4 response prevent DNA damage and potentially mutagenic replication to safeguard genome stability.


Subject(s)
DNA Primase , DNA Replication , DNA-Binding Proteins , G-Quadruplexes , Genomic Instability , MutS Homolog 2 Protein , Transcription Factors , Humans , Transcription Factors/metabolism , Transcription Factors/genetics , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/genetics , MutS Homolog 2 Protein/metabolism , MutS Homolog 2 Protein/genetics , DNA Primase/metabolism , DNA Primase/genetics , Telomere Homeostasis , DNA Damage , HEK293 Cells , Multifunctional Enzymes/metabolism , Multifunctional Enzymes/genetics , DNA-Directed DNA Polymerase
12.
Int J Mol Sci ; 25(16)2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39201341

ABSTRACT

The number of infertile couples undergoing in vitro fertilisation (IVF) has increased significantly. The efficacy of this procedure is contingent upon a multitude of factors, including gamete quality. One factor influencing gamete quality is oxidative stress, which leads to telomere damage and accelerates cellular ageing. Identifying new biomarkers that can predict the success of assisted reproduction techniques is a current relevant area of research. In this review, we discuss the potential role of SIRT1, a protein known to protect against oxidative stress and telomeres, which are responsible for genome stability, as biomarkers of gamete quality and assisted reproduction technique outcomes.


Subject(s)
Biomarkers , Fertilization in Vitro , Oxidative Stress , Sirtuin 1 , Telomere , Humans , Fertilization in Vitro/methods , Telomere/metabolism , Telomere/genetics , Sirtuin 1/metabolism , Sirtuin 1/genetics , Germ Cells/metabolism , Fertility/genetics , Female , Male
13.
Genes (Basel) ; 15(8)2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39202386

ABSTRACT

Fluorescence in situ hybridization (FISH) with two different probes, the canonical insect telomeric sequence (TTAGG)n and the sequence (TTAGGGATGG)n, was performed on meiotic chromosomes of two members of the true bug family Cimicidae (Cimicomorpha), the common bed bug Cimex lectularius Linnaeus, 1758 and the tropical bed bug C. hemipterus (Fabricius, 1803), whose telomeric motifs were not known. In both species, there were no hybridization signals with the first probe, but strong signals at chromosomal ends were observed with the second probe, indicating the presence of a telomeric motif (TTAGGGATGG)n. This study represents the first FISH confirmation of the presence of a non-canonical telomeric motif not only for the infraorder Cimicomorpha but also for the suborder Heteroptera (Hemiptera) as a whole. The present finding is of key significance for unraveling the evolutionary shifts in the telomeric sequences in this suborder.


Subject(s)
In Situ Hybridization, Fluorescence , Telomere , Animals , Telomere/genetics , Heteroptera/genetics , Nucleotide Motifs/genetics , Chromosomes, Insect/genetics
14.
Schizophr Res ; 272: 89-95, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39208769

ABSTRACT

OBJECTIVE: Contemporary research suggests reduced telomere length in schizophrenia spectrum disorders (SZ) compared to age-adjusted non-affected individuals. However, the role of telomere maintenance and telomere repair in SZ is poorly understood as well as the involvement of telomere biology in cognitive abnormalities in SZ. METHODS: The study consisted of 758 participants (SZ [n = 357] and healthy controls, HC [n = 401]) collected as part of the Norwegian TOP study. Participants were assessed with standardized neuropsychological tests measuring five cognitive domains. Leucocyte telomere length (TL) was measured via blood and determined by quantitative real-time Polymerase Chain Reaction (qPCR) providing a telomere to single copy ratio (T/S ratio), used to estimate the mean telomere length. Telomerase activity was assessed by the expression levels of the Telomerase Reverse Transcriptase (TERT) and Telomerase RNA Component (TERC) genes. To assess telomere maintenance and telomere repair we calculated the telomerase expression to TL ratio (TERT/TL and TERC/TL respectively). RESULTS: Patients had reduced TERT (F = 5.03, p = 0.03), but not TERC expression (F = 1.04, p = 0.31), and higher TERT/TL (F = 6.68, p = 0.01) and TERC/TL (F = 6.71, p = 0.01), adjusted for age, sex, and ethnicity. No statistically significant association was observed between any of the telomere biology markers and the cognitive domains (p > 0.05). CONCLUSION: Our study shows changes in TERT expression and telomere maintenance and telomere repair in SZ compared HC. However, the role of telomere biology in the mechanism underlying cognitive impairment in psychosis seems limited.


Subject(s)
Schizophrenia , Telomerase , Telomere , Humans , Female , Male , Telomerase/genetics , Schizophrenia/genetics , Schizophrenia/physiopathology , Adult , Middle Aged , RNA/genetics , Cognitive Dysfunction/etiology , Cognitive Dysfunction/genetics , Cognitive Dysfunction/physiopathology , Leukocytes/metabolism , Neuropsychological Tests , Telomere Homeostasis/physiology , Schizophrenic Psychology , Telomere Shortening/physiology , Psychotic Disorders/genetics , Psychotic Disorders/physiopathology
15.
Biochem Soc Trans ; 52(4): 1551-1564, 2024 08 28.
Article in English | MEDLINE | ID: mdl-39109533

ABSTRACT

The six-subunit shelterin complex binds to mammalian telomeres and protects them from triggering multiple DNA damage response pathways. The loss of this protective function by shelterin can have detrimental effects on cells. In this review, we first discuss structural studies of shelterin, detailing the contributions of each subunit and inter-subunit interactions in protecting chromosome ends. We then examine the influence of telomeric chromatin dynamics on the function of shelterin at telomeres. These studies provide valuable insights and underscore the challenges that future research must tackle to attain high-resolution structures of shelterin.


Subject(s)
Chromatin , Shelterin Complex , Telomere-Binding Proteins , Telomere , Telomere/metabolism , Chromatin/metabolism , Chromatin/chemistry , Humans , Shelterin Complex/metabolism , Telomere-Binding Proteins/metabolism , Telomere-Binding Proteins/chemistry , Animals , DNA Damage , Protein Binding
16.
Biochem Soc Trans ; 52(4): 1957-1968, 2024 08 28.
Article in English | MEDLINE | ID: mdl-39194999

ABSTRACT

Telomerase, crucial for maintaining telomere length, is an attractive target for cancer therapy due to its role in cellular immortality. Despite three decades of research efforts, no small-molecule telomerase inhibitors have been clinically approved, highlighting the extensive challenges in developing effective telomerase-based therapeutics. This review examines conventional and emerging methods to measure telomerase activity and discusses existing inhibitors, including oligonucleotides and small molecules. Furthermore, this review highlights recent breakthroughs in structural studies of telomerase using cryo-electron microscopy, which can facilitate improved structure-based drug design. Altogether, advancements in structural methodologies and high-throughput screening offer promising prospects for telomerase-based cancer therapeutic development.


Subject(s)
Drug Discovery , Enzyme Inhibitors , Telomerase , Telomerase/antagonists & inhibitors , Telomerase/metabolism , Humans , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic use , Drug Discovery/methods , Cryoelectron Microscopy , Neoplasms/drug therapy , Drug Design , Telomere/metabolism , Oligonucleotides/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use
17.
Int J Biol Macromol ; 277(Pt 3): 134300, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39097069

ABSTRACT

Extensive bodies of research are dedicated to the study of seed aging with a particular focus on the roles of reactive oxygen species (ROS), and the ensuing oxidative damage during storage, as a primary cause of seed vigor decreasing. ROS diffuse to the nucleus and damage the telomeres, resulting in a loss of genetic integrity. Protection of telomeres 1 (POT1) is a telomeric protein that binds to the telomere region, and plays an essential role in maintaining genomic stability in plants. In this study, there were totally four MsPOT1 genes obtained from alfalfa genome. Expression analysis of four MsPOT1 genes in germinated seed presented the different expressions. Four MsPOT1 genes displayed high expression levels at the early stage of seed germination, Among the four POT1 genes, it was found that MS. gene040108 was significantly up-regulated in the early germination stage of CK seeds, but down-regulated in aged seeds. RT-qPCR assays and RNA-seq data revealed that MsPOT1-X gene was significantly induced by seed aging treatment. Transgenic seeds overexpressing MsPOT1-X gene in Arabidopsis thaliana and Medicago trunctula exhibited enhanced seed vigor, telomere length, telomerase activity associated with reduced H2O2 content. These results would provide a new way to understand aging stress-responsive MsPOT1 genes for genetic improvement of seed vigor. Although a key gene regulating seed vigor was identified in this study, the specific mechanism of MsPOT1-X gene regulating seed vigor needs to be further explored.


Subject(s)
Gene Expression Regulation, Plant , Medicago sativa , Plant Proteins , Seeds , Medicago sativa/genetics , Medicago sativa/metabolism , Seeds/genetics , Seeds/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Telomere/metabolism , Telomere/genetics , Germination/genetics , Plants, Genetically Modified , Telomere-Binding Proteins/metabolism , Telomere-Binding Proteins/genetics , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis/growth & development , Reactive Oxygen Species/metabolism
18.
Int J Mol Sci ; 25(15)2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39126110

ABSTRACT

Understanding the complex dynamics of telomere biology is important in the strong link between aging and cancer. Telomeres, the protective caps at the end of chromosomes, are central players in this connection. While their gradual shortening due to replication limits tumors expansion by triggering DNA repair mechanisms, it also promotes oncogenic changes within chromosomes, thus sustaining tumorigenesis. The enzyme telomerase, responsible for maintaining telomere length, emerges as a central player in this context. Its expression in cancer cells facilitates the preservation of telomeres, allowing them to circumvent the growth-limiting effects of short telomeres. Interestingly, the influence of telomerase extends beyond telomere maintenance, as evidenced by its involvement in promoting cell growth through alternative pathways. In this context, inflammation accelerates telomere shortening, resulting in telomere dysfunction, while telomere elements also play a role in modulating the inflammatory response. The recognition of this interplay has promoted the development of novel therapeutic approaches centered around telomerase inhibition. This review provides a comprehensive overview of the field, emphasizing recent progress in knowledge and the implications in understanding of cancer biology.


Subject(s)
Aging , Inflammation , Neoplasms , Telomerase , Telomere , Telomerase/metabolism , Humans , Inflammation/metabolism , Inflammation/pathology , Neoplasms/metabolism , Neoplasms/pathology , Neoplasms/genetics , Aging/metabolism , Aging/genetics , Animals , Telomere/metabolism , Telomere/genetics , Telomere Homeostasis , Telomere Shortening
19.
Front Vet Sci ; 11: 1430861, 2024.
Article in English | MEDLINE | ID: mdl-39170634

ABSTRACT

Aging is a complex process influenced by internal and external factors. Oxidative stress damages DNA, leading to 8-hydroxy-2' deoxyguanosine formation (8-OHdG). Telomere shortening is considered a biomarker of aging and oxidative stress may enhance its attrition. The ability to manage and repair oxidative stress varies among species and life histories. Avian species, such as Psittacidae birds, exhibit exceptional lifespans despite their physiological characteristics that might suggest otherwise. This study investigates 8-OHdG levels in serum samples from long- and short-lived birds of the order Psittaciformes, examining their relationship with telomere length and antioxidant capacity based on lifespan strategies. Among 43 individuals analyzed 26 belonged to the "long-lived species" group and 17 belonged to the "short-lived species" one. Relative telomere length (rTL) was measured in DNA isolated from whole blood by qPCR, and oxidative stress markers, such as Total Antioxidant Capacity (TAC) and 8-OHdG, were determined by spectrophotometry in serum samples. Long-lived birds had longer rTL than short-lived ones [1.308 ± 0.11 vs. 0.565 ± 0.13, (p < 0.001)]. On the contrary, short-lived birds showed more DNA damage than their counterparts [3.847 ± 0.351 vs. 2.012 ± 0.308, respectively, (p < 0.001)]. Old birds had shorter rTL than young ones, for both longevity groups (p < 0.001). Although no correlation was found between 8-OHdG levels and age, nor 8-OHdG and telomere length, long-lived birds exhibited 75.42-unit increased TAC levels when increased 8-OHdG concentrations (p = 0.046). These findings highlight distinct patterns of telomere length and oxidative stress influenced by lifespan strategies among avian longevity groups.

20.
Int J Mol Sci ; 25(15)2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39125728

ABSTRACT

Persistent high-risk human papillomaviruses (HR HPVs) infection leads to the development of squamous intraepithelial lesions in cervical cells that may lead to cancer. The telomere length, telomerase activity, and species composition of the vaginal microbiome may influence the dynamic of changes and the process of carcinogenesis. In the present study, we analyze relative telomere length (RTL), relative hTERT expression (gene for the telomerase component-reverse transcriptase) in cervical smear cells and vaginal microbiomes. Total RNA and DNA were isolated from tissue samples of 109 patients from the following groups: control, carrier, low-grade or high-grade squamous intraepithelial lesion (L SIL and H SIL, respectively), and cancer. The quantitative PCR method was used to measure telomere length and telomerase expression. Vaginal microbiome bacteria were divided into community state types using morphotype criteria. Significant differences between histopathology groups were confirmed for both relative telomere length and relative hTERT expression (p < 0.001 and p = 0.001, respectively). A significant difference in RTL was identified between carriers and H SIL (p adj < 0.001) groups, as well as between carriers and L SIL groups (p adj = 0.048). In both cases, RTL was lower among carriers. The highest relative hTERT expression level was recorded in the H SIL group, and the highest relative hTERT expression level was recorded between carriers and the H SIL group (p adj < 0.001). A correlation between genotype and biocenosis was identified for genotype 16+A (p < 0.001). The results suggest that identification of HPV infection, telomere length assessment, and hTERT expression measurement together may be more predictive than each of these analyses performed separately.


Subject(s)
Microbiota , Papillomavirus Infections , Precancerous Conditions , Telomerase , Telomere , Uterine Cervical Neoplasms , Vagina , Humans , Female , Telomerase/metabolism , Telomerase/genetics , Vagina/microbiology , Vagina/virology , Microbiota/genetics , Papillomavirus Infections/virology , Papillomavirus Infections/complications , Papillomavirus Infections/genetics , Adult , Telomere/metabolism , Telomere/genetics , Middle Aged , Precancerous Conditions/virology , Precancerous Conditions/microbiology , Precancerous Conditions/genetics , Precancerous Conditions/pathology , Uterine Cervical Neoplasms/virology , Uterine Cervical Neoplasms/microbiology , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/pathology , Telomere Homeostasis , Papillomaviridae/genetics
SELECTION OF CITATIONS
SEARCH DETAIL