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1.
Hum Genomics ; 18(1): 56, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38831447

ABSTRACT

BACKGROUND: Several lines of evidence suggest that leukocyte telomere length (LTL) can affect the development of prostate cancer (PC). METHODS: Here, we employed single nucleoside polymorphisms (SNPs) as instrumental variables (IVs) for LTL (n = 472,174) and conducted Mendelian randomization analysis to estimate their causal impact on PCs (79,148 patients/61,106 controls and 6311 patients/88,902 controls). RESULTS: Every 1-s.d extension of LTL increased the risk of PCs by 34%. Additionally, the analysis of candidate mediators between LTL and PCs via two-step Mendelian randomization revealed that among the 23 candidates, Alzheimer's disease, liver iron content, sex hormone binding global levels, naive CD4-CD8-T cell% T cell, and circulating leptin levels played substantial mediating roles. There is no robust evidence to support the reverse causal relationship between LTL and the selected mediators of PCs. Adjusting for the former four mediators, rather than adjusting for circulating leptin levels, decreased the impact of LTL on PCs. CONCLUSION: This study provides potential intervention measures for preventing LTL-induced PCs.


Subject(s)
Leukocytes , Mendelian Randomization Analysis , Polymorphism, Single Nucleotide , Prostatic Neoplasms , Telomere , White People , Humans , Male , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Leukocytes/metabolism , Polymorphism, Single Nucleotide/genetics , White People/genetics , Telomere/genetics , Telomere Homeostasis/genetics , Leptin/genetics , Leptin/blood , Genetic Predisposition to Disease , Aged , Middle Aged
2.
Nat Commun ; 15(1): 4707, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38830842

ABSTRACT

Persisting replication intermediates can confer mitotic catastrophe. Loss of the fission yeast telomere protein Taz1 (ortholog of mammalian TRF1/TRF2) causes telomeric replication fork (RF) stalling and consequently, telomere entanglements that stretch between segregating mitotic chromosomes. At ≤20 °C, these entanglements fail to resolve, resulting in lethality. Rif1, a conserved DNA replication/repair protein, hinders the resolution of telomere entanglements without affecting their formation. At mitosis, local nuclear envelope (NE) breakdown occurs in the cell's midregion. Here we demonstrate that entanglement resolution occurs in the cytoplasm following this NE breakdown. However, in response to taz1Δ telomeric entanglements, Rif1 delays midregion NE breakdown at ≤20 °C, in turn disfavoring entanglement resolution. Moreover, Rif1 overexpression in an otherwise wild-type setting causes cold-specific NE defects and lethality, which are rescued by membrane fluidization. Hence, NE properties confer the cold-specificity of taz1Δ lethality, which stems from postponement of NE breakdown. We propose that such postponement promotes clearance of simple stalled RFs, but resolution of complex entanglements (involving strand invasion between nonsister telomeres) requires rapid exposure to the cytoplasm.


Subject(s)
Anaphase , Nuclear Envelope , Schizosaccharomyces pombe Proteins , Schizosaccharomyces , Telomere-Binding Proteins , Telomere , Nuclear Envelope/metabolism , Schizosaccharomyces/genetics , Schizosaccharomyces/metabolism , Telomere/metabolism , Schizosaccharomyces pombe Proteins/metabolism , Schizosaccharomyces pombe Proteins/genetics , Telomere-Binding Proteins/metabolism , Telomere-Binding Proteins/genetics , DNA Replication
3.
Nat Commun ; 15(1): 4681, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824190

ABSTRACT

The telomere sequence, TTAGGG, is conserved across all vertebrates and plays an essential role in suppressing the DNA damage response by binding a set of proteins termed shelterin. Changes in the telomere sequence impair shelterin binding, initiate a DNA damage response, and are toxic to cells. Here we identify a family with a variant in the telomere template sequence of telomerase, the enzyme responsible for telomere elongation, that led to a non-canonical telomere sequence. The variant is inherited across at least one generation and one family member reports no significant medical concerns despite ~9% of their telomeres converting to the novel sequence. The variant template disrupts telomerase repeat addition processivity and decreased the binding of the telomere-binding protein POT1. Despite these disruptions, the sequence is readily incorporated into cellular chromosomes. Incorporation of a variant sequence prevents POT1-mediated inhibition of telomerase suggesting that incorporation of a variant sequence may influence telomere addition. These findings demonstrate that telomeres can tolerate substantial degeneracy while remaining functional and provide insights as to how incorporation of a non-canonical telomere sequence might alter telomere length dynamics.


Subject(s)
Pedigree , Shelterin Complex , Telomerase , Telomere-Binding Proteins , Telomere , Humans , Telomere/metabolism , Telomere/genetics , Telomere-Binding Proteins/metabolism , Telomere-Binding Proteins/genetics , Shelterin Complex/metabolism , Telomerase/genetics , Telomerase/metabolism , Male , Female , Telomere Homeostasis/genetics , Base Sequence , Adult
4.
Sci Adv ; 10(18): eadl1922, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38691604

ABSTRACT

The most common form of facioscapulohumeral dystrophy (FSHD1) is caused by a partial loss of the D4Z4 macrosatellite repeat array in the subtelomeric region of chromosome 4. Patients with FSHD1 typically carry 1 to 10 D4Z4 repeats, whereas nonaffected individuals have 11 to 150 repeats. The ~150-kilobyte subtelomeric region of the chromosome 10q exhibits a ~99% sequence identity to the 4q, including the D4Z4 array. Nevertheless, contractions of the chr10 array do not cause FSHD or any known disease, as in most people D4Z4 array on chr10 is flanked by the nonfunctional polyadenylation signal, not permitting the DUX4 expression. Here, we attempted to correct the FSHD genotype by a CRISPR-Cas9-induced exchange of the chr4 and chr10 subtelomeric regions. We demonstrated that the induced t(4;10) translocation can generate recombinant genotypes translated into improved FSHD phenotype. FSHD myoblasts with the t(4;10) exhibited reduced expression of the DUX4 targets, restored PAX7 target expression, reduced sensitivity to oxidative stress, and improved differentiation capacity.


Subject(s)
Chromosomes, Human, Pair 10 , Chromosomes, Human, Pair 4 , Genotype , Homeodomain Proteins , Muscular Dystrophy, Facioscapulohumeral , Phenotype , Telomere , Humans , Chromosomes, Human, Pair 10/genetics , Chromosomes, Human, Pair 4/genetics , CRISPR-Cas Systems , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Muscular Dystrophy, Facioscapulohumeral/genetics , Myoblasts/metabolism , PAX7 Transcription Factor/genetics , PAX7 Transcription Factor/metabolism , Telomere/genetics , Telomere/metabolism , Translocation, Genetic
5.
Mol Plant Pathol ; 25(5): e13460, 2024 May.
Article in English | MEDLINE | ID: mdl-38695626

ABSTRACT

Reverse genetic approaches are common tools in genomics for elucidating gene functions, involving techniques such as gene deletion followed by screening for aberrant phenotypes. If the generation of gene deletion mutants fails, the question arises whether the failure stems from technical issues or because the gene of interest (GOI) is essential, meaning that the deletion causes lethality. In this report, we introduce a novel method for assessing gene essentiality using the phytopathogenic ascomycete Magnaporthe oryzae. The method is based on the observation that telomere vectors are lost in transformants during cultivation without selection pressure. We tested the hypothesis that essential genes can be identified in deletion mutants co-transformed with a telomere vector. The M. oryzae gene MoPKC, described in literature as essential, was chosen as GOI. Using CRISPR/Cas9 technology transformants with deleted GOI were generated and backed up by a telomere vector carrying a copy of the GOI and conferring fenhexamid resistance. Transformants in which the GOI deletion in the genome was not successful lost the telomere vector on media without fenhexamid. In contrast, transformants with confirmed GOI deletion retained the telomere vector even in absence of fenhexamid selection. In the latter case, the maintenance of the telomere indicates that the GOI is essential for the surveillance of the fungi, as it would have been lost otherwise. The method presented here allows to test for essentiality of genes when no mutants can be obtained from gene deletion approaches, thereby expanding the toolbox for studying gene function in ascomycetes.


Subject(s)
Ascomycota , Genes, Essential , Genetic Vectors , Phenotype , Telomere , Telomere/genetics , Genetic Vectors/genetics , CRISPR-Cas Systems/genetics , Genes, Fungal/genetics , Gene Deletion , Magnaporthe/genetics , Magnaporthe/pathogenicity
6.
Am J Hum Genet ; 111(5): 927-938, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38701745

ABSTRACT

Leukocyte telomere length (LTL) varies significantly across human populations, with individuals of African ancestry having longer LTL than non-Africans. However, the genetic and environmental drivers of LTL variation in Africans remain largely unknown. We report here on the relationship between LTL, genetics, and a variety of environmental and climatic factors in ethnically diverse African adults (n = 1,818) originating from Botswana, Tanzania, Ethiopia, and Cameroon. We observe significant variation in LTL among populations, finding that the San hunter-gatherers from Botswana have the longest leukocyte telomeres and that the Fulani pastoralists from Cameroon have the shortest telomeres. Genetic factors explain ∼50% of LTL variation among individuals. Moreover, we observe a significant negative association between Plasmodium falciparum malaria endemicity and LTL while adjusting for age, sex, and genetics. Within Africa, adults from populations indigenous to areas with high malaria exposure have shorter LTL than those in populations indigenous to areas with low malaria exposure. Finally, we explore to what degree the genetic architecture underlying LTL in Africa covaries with malaria exposure.


Subject(s)
Malaria, Falciparum , Telomere , Humans , Malaria, Falciparum/genetics , Malaria, Falciparum/epidemiology , Malaria, Falciparum/parasitology , Male , Female , Adult , Africa South of the Sahara/epidemiology , Telomere/genetics , Endemic Diseases , Plasmodium falciparum/genetics , Plasmodium falciparum/pathogenicity , Black People/genetics , Middle Aged , Leukocytes/metabolism , Telomere Homeostasis/genetics , Young Adult , Sub-Saharan African People
7.
Viruses ; 16(5)2024 05 10.
Article in English | MEDLINE | ID: mdl-38793637

ABSTRACT

BACKGROUND: Chronic/latent viral infections may accelerate immunological aging, particularly among people living with HIV (PLWH). We characterized chronic/latent virus infections across their lifespan and investigated their associations with leukocyte telomere length (LTL). METHODS: Participants enrolled in the CARMA cohort study were randomly selected to include n = 15 for each decade of age between 0 and >60 y, for each sex, and each HIV status. Cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 8 (HHV-8), herpes simplex virus 1 (HSV-1), and HSV-2 infection were determined serologically; HIV, hepatitis C (HCV), and hepatitis B (HBV) were self-reported. LTLs were measured using monochrome multiplex qPCR. Associations between the number of viruses, LTL, and sociodemographic factors were assessed using ordinal logistic and linear regression modeling. RESULTS: The study included 187 PLWH (105 female/82 male) and 190 HIV-negative participants (105 female/84 male), ranging in age from 0.7 to 76.1 years. Living with HIV, being older, and being female were associated with harbouring a greater number of chronic/latent non-HIV viruses. Having more infections was in turn bivariately associated with a shorter LTL. In multivariable analyses, older age, living with HIV, and the female sex remained independently associated with having more infections, while having 3-4 viruses (vs. 0-2) was associated with a shorter LTL. CONCLUSIONS: Our results suggest that persistent viral infections are more prevalent in PLWH and females, and that these may contribute to immunological aging. Whether this is associated with comorbidities later in life remains an important question.


Subject(s)
HIV Infections , Leukocytes , Humans , Female , HIV Infections/virology , HIV Infections/immunology , Male , Leukocytes/virology , Middle Aged , Adult , Aged , Young Adult , Adolescent , Child , Telomere/genetics , Infant , Child, Preschool , Latent Infection/virology , Virus Diseases/virology , Virus Diseases/immunology , Chronic Disease , Cohort Studies , Infant, Newborn
8.
Nutrients ; 16(10)2024 May 08.
Article in English | MEDLINE | ID: mdl-38794655

ABSTRACT

The aim of this study was to assess the causal relationships between mineral metabolism disorders, representative of trace elements, and key aging biomarkers: telomere length (TL) and mitochondrial DNA copy number (mtDNA-CN). Utilizing bidirectional Mendelian randomization (MR) analysis in combination with the two-stage least squares (2SLS) method, we explored the causal relationships between mineral metabolism disorders and these aging indicators. Sensitivity analysis can be used to determine the reliability and robustness of the research results. The results confirmed that a positive causal relationship was observed between mineral metabolism disorders and TL (p < 0.05), while the causal relationship with mtDNA-CN was not significant (p > 0.05). Focusing on subgroup analyses of specific minerals, our findings indicated a distinct positive causal relationship between iron metabolism disorders and both TL and mtDNA-CN (p < 0.05). In contrast, disorders in magnesium and phosphorus metabolism did not exhibit significant causal effects on either aging biomarker (p > 0.05). Moreover, reverse MR analysis did not reveal any significant causal effects of TL and mtDNA-CN on mineral metabolism disorders (p > 0.05). The combination of 2SLS with MR analysis further reinforced the positive causal relationship between iron levels and both TL and mtDNA-CN (p < 0.05). Notably, the sensitivity analysis did not indicate significant pleiotropy or heterogeneity within these causal relationships (p > 0.05). These findings highlight the pivotal role of iron metabolism in cellular aging, particularly in regulating TL and sustaining mtDNA-CN, offering new insights into how mineral metabolism disorders influence aging biomarkers. Our research underscores the importance of trace element balance, especially regarding iron intake, in combating the aging process. This provides a potential strategy for slowing aging through the adjustment of trace element intake, laying the groundwork for future research into the relationship between trace elements and healthy aging.


Subject(s)
DNA, Mitochondrial , Mendelian Randomization Analysis , Telomere , Humans , DNA, Mitochondrial/genetics , Telomere/metabolism , Minerals/metabolism , Aging/genetics , DNA Copy Number Variations , Trace Elements/blood , Iron/metabolism , Iron/blood , Biomarkers/blood
9.
Int J Nanomedicine ; 19: 3805-3825, 2024.
Article in English | MEDLINE | ID: mdl-38708177

ABSTRACT

Telomere is a protective structure located at the end of chromosomes of eukaryotes, involved in maintaining the integrity and stability of the genome. Telomeres play an essential role in cancer progression; accordingly, targeting telomere dynamics emerges as an effective approach for the development of cancer therapeutics. Targeting telomere dynamics may work through multifaceted molecular mechanisms; those include the activation of anti-telomerase immune responses, shortening of telomere lengths, induction of telomere dysfunction and constitution of telomerase-responsive drug release systems. In this review, we summarize a wide variety of telomere dynamics-targeted agents in preclinical studies and clinical trials, and reveal their promising therapeutic potential in cancer therapy. As shown, telomere dynamics-active agents are effective as anti-cancer chemotherapeutics and immunotherapeutics. Notably, these agents may display efficacy against cancer stem cells, reducing cancer stem levels. Furthermore, these agents can be integrated with the capability of tumor-specific drug delivery by the constitution of related nanoparticles, antibody drug conjugates and HSA-based drugs.


Subject(s)
Antineoplastic Agents , Neoplasms , Telomerase , Telomere , Humans , Neoplasms/drug therapy , Neoplasms/therapy , Telomere/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Telomerase/antagonists & inhibitors , Animals , Drug Delivery Systems/methods , Nanoparticles/chemistry , Immunotherapy/methods , Neoplastic Stem Cells/drug effects
10.
Sci Rep ; 14(1): 11208, 2024 05 16.
Article in English | MEDLINE | ID: mdl-38755232

ABSTRACT

The mechanisms that underlie senescence are not well understood in insects. Telomeres are conserved repetitive sequences at chromosome ends that protect DNA during replication. In many vertebrates, telomeres shorten during cell division and in response to stress and are often used as a cellular marker of senescence. However, little is known about telomere dynamics across the lifespan in invertebrates. We measured telomere length in larvae, prepupae, pupae, and adults of two species of solitary bees, Osmia lignaria and Megachile rotundata. Contrary to our predictions, telomere length was longer in later developmental stages in both O. lignaria and M. rotundata. Longer telomeres occurred after emergence from diapause, which is a physiological state with increased tolerance to stress. In O. lignaria, telomeres were longer in adults when they emerged following diapause. In M. rotundata, telomeres were longer in the pupal stage and subsequent adult stage, which occurs after prepupal diapause. In both species, telomere length did not change during the 8 months of diapause. Telomere length did not differ by mass similarly across species or sex. We also did not see a difference in telomere length after adult O. lignaria were exposed to a nutritional stress, nor did length change during their adult lifespan. Taken together, these results suggest that telomere dynamics in solitary bees differ from what is commonly reported in vertebrates and suggest that insect diapause may influence telomere dynamics.


Subject(s)
Telomere , Animals , Bees/genetics , Bees/physiology , Telomere/genetics , Telomere/metabolism , Pupa/growth & development , Pupa/genetics , Female , Male , Telomere Homeostasis , Larva/genetics , Larva/growth & development , Larva/physiology , Diapause/genetics
11.
BMC Bioinformatics ; 25(1): 194, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38755561

ABSTRACT

Telomeres are regions of repetitive DNA at the ends of linear chromosomes which protect chromosome ends from degradation. Telomere lengths have been extensively studied in the context of aging and disease, though most studies use average telomere lengths which are of limited utility. We present a method for identifying all 92 telomere alleles from long read sequencing data. Individual telomeres are identified using variant repeats proximal to telomere regions, which are unique across alleles. This high-throughput and high-resolution characterization of telomeres could be foundational to future studies investigating the roles of specific telomeres in aging and disease.


Subject(s)
Alleles , Telomere , Telomere/genetics , Humans , Sequence Analysis, DNA/methods , High-Throughput Nucleotide Sequencing/methods , Repetitive Sequences, Nucleic Acid/genetics
12.
PLoS One ; 19(5): e0303357, 2024.
Article in English | MEDLINE | ID: mdl-38743757

ABSTRACT

Short telomeres are associated with cardiovascular disease (CVD). We aimed to investigate, if genetically determined telomere-length effects CVD-risk in the Heinz-Nixdorf-Recall study (HNRS) population. We selected 14 single-nucleotide polymorphisms (SNPs) associated with telomere-length (p<10-8) from the literature and after exclusion 9 SNPs were included in the analyses. Additionally, a genetic risk score (GRS) using these 9 SNPs was calculated. Incident CVD was defined as fatal and non-fatal myocardial infarction, stroke, and coronary death. We included 3874 HNRS participants with available genetic data and had no known history of CVD at baseline. Cox proportional-hazards regression was used to test the association between the SNPs/GRS and incident CVD-risk adjusting for common CVD risk-factors. The analyses were further stratified by CVD risk-factors. During follow-up (12.1±4.31 years), 466 participants experienced CVD-events. No association between SNPs/GRS and CVD was observed in the adjusted analyses. However, the GRS, rs10936599, rs2487999 and rs8105767 increase the CVD-risk in current smoker. Few SNPs (rs10936599, rs2487999, and rs7675998) showed an increased CVD-risk, whereas rs10936599, rs677228 and rs4387287 a decreased CVD-risk, in further strata. The results of our study suggest different effects of SNPs/GRS on CVD-risk depending on the CVD risk-factor strata, highlighting the importance of stratified analyses in CVD risk-factors.


Subject(s)
Cardiovascular Diseases , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Telomere , Humans , Cardiovascular Diseases/genetics , Male , Female , Middle Aged , Aged , Telomere/genetics , Risk Factors , Telomere Homeostasis/genetics
13.
Nat Commun ; 15(1): 4061, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38744897

ABSTRACT

Transcription stress has been linked to DNA damage -driven aging, yet the underlying mechanism remains unclear. Here, we demonstrate that Tcea1-/- cells, which harbor a TFIIS defect in transcription elongation, exhibit RNAPII stalling at oxidative DNA damage sites, impaired transcription, accumulation of R-loops, telomere uncapping, chromatin bridges, and genome instability, ultimately resulting in cellular senescence. We found that R-loops at telomeres causally contribute to the release of telomeric DNA fragments in the cytoplasm of Tcea1-/- cells and primary cells derived from naturally aged animals triggering a viral-like immune response. TFIIS-defective cells release extracellular vesicles laden with telomeric DNA fragments that target neighboring cells, which consequently undergo cellular senescence. Thus, transcription stress elicits paracrine signals leading to cellular senescence, promoting aging.


Subject(s)
Cellular Senescence , Cytosol , DNA Damage , Paracrine Communication , Telomere , Cellular Senescence/genetics , Animals , Telomere/metabolism , Telomere/genetics , Mice , Cytosol/metabolism , DNA/metabolism , Transcription, Genetic , Mice, Knockout , Humans , Extracellular Vesicles/metabolism , Genomic Instability , Aging/genetics , Aging/metabolism , Oxidative Stress , Mice, Inbred C57BL
14.
Sci Rep ; 14(1): 11711, 2024 05 22.
Article in English | MEDLINE | ID: mdl-38777848

ABSTRACT

Achieving successful pregnancy outcomes is a delicate interplay between the maternal and the fetal counterparts. Paternal factors play a critical role in health and disease of offspring. Early pregnancy loss (EPL) is a psychologically devastating condition affecting the quality of life (QOL). Thus, it needs to be managed by a mind body integrated approach like yoga.The prospective single arm exploratory studyincluded male partners of couples experiencing recurrent pregnancy loss (RPL, n = 30), and recurrent implantation failure (RIF, n = 30) and semen samples wereassessed at the beginning and completion of yoga (6 weeks) (WHO 2010).A significant increase in the sperm concentration, motility, decrease in seminal ROS, DFI and increase in relative sperm telomere length was found at the end of yoga. The relative expression of genes critical for early embryonic developmentnormalized towards the levels of controls. WHOQOL-BREF questionnaire scores to assess QOL also showed improvement.Integration of regular practice yoga into our lifestyle may help in improving seminal redox status, genomic integrity, telomere length, normalizing gene expression and QOL, highlighting the need to use an integrated, holistic approach in management of such cases. This is pertinent for decreasing the transmission of mutation and epimutation load to the developing embryo, improving pregnancy outcomes and decreasing genetic and epigenetic disease burden in the next generation.


Subject(s)
Quality of Life , Spermatozoa , Yoga , Humans , Male , Female , Pregnancy , Spermatozoa/metabolism , Adult , Abortion, Habitual/genetics , Abortion, Habitual/psychology , Abortion, Habitual/therapy , Telomere/genetics , Telomere/metabolism , Prospective Studies , Telomere Homeostasis , Sperm Motility/genetics
16.
Clin Epigenetics ; 16(1): 68, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38773655

ABSTRACT

BACKGROUND: Large B-cell lymphoma (LBCL) is the most common lymphoma and is known to be a biologically heterogeneous disease regarding genetic, phenotypic, and clinical features. Although the prognosis is good, one-third has a primary refractory or relapsing disease which underscores the importance of developing predictive biological markers capable of identifying high- and low-risk patients. DNA methylation (DNAm) and telomere maintenance alterations are hallmarks of cancer and aging. Both these alterations may contribute to the heterogeneity of the disease, and potentially influence the prognosis of LBCL. RESULTS: We studied the DNAm profiles (Infinium MethylationEPIC BeadChip) and relative telomere lengths (RTL) with qPCR of 93 LBCL cases: Diffuse large B-cell lymphoma not otherwise specified (DLBCL, n = 66), High-grade B-cell lymphoma (n = 7), Primary CNS lymphoma (n = 8), and transformation of indolent B-cell lymphoma (n = 12). There was a substantial methylation heterogeneity in DLBCL and other LBCL entities compared to normal cells and other B-cell neoplasms. LBCL cases had a particularly aberrant semimethylated pattern (0.15 ≤ ß ≤ 0.8) with large intertumor variation and overall low hypermethylation (ß > 0.8). DNAm patterns could not be used to distinguish between germinal center B-cell-like (GC) and non-GC DLBCL cases. In cases treated with R-CHOP-like regimens, a high percentage of global hypomethylation (ß < 0.15) was in multivariable analysis associated with worse disease-specific survival (DSS) (HR 6.920, 95% CI 1.499-31.943) and progression-free survival (PFS) (HR 4.923, 95% CI 1.286-18.849) in DLBCL and with worse DSS (HR 5.147, 95% CI 1.239-21.388) in LBCL. These cases with a high percentage of global hypomethylation also had a higher degree of CpG island methylation, including islands in promoter-associated regions, than the cases with less hypomethylation. Additionally, telomere length was heterogenous in LBCL, with a subset of the DLBCL-GC cases accounting for the longest RTL. Short RTL was independently associated with worse DSS (HR 6.011, 95% CI 1.319-27.397) and PFS (HR 4.689, 95% CI 1.102-19.963) in LBCL treated with R-CHOP-like regimens. CONCLUSION: We hypothesize that subclones with high global hypomethylation and hypermethylated CpG islands could have advantages in tumor progression, e.g. by inactivating tumor suppressor genes or promoting treatment resistance. Our findings suggest that cases with high global hypomethylation and thus poor prognosis could be candidates for alternative treatment regimens including hypomethylating drugs.


Subject(s)
DNA Methylation , Lymphoma, Large B-Cell, Diffuse , Humans , Lymphoma, Large B-Cell, Diffuse/genetics , Lymphoma, Large B-Cell, Diffuse/mortality , DNA Methylation/genetics , Female , Male , Prognosis , Middle Aged , Aged , Adult , Rituximab/therapeutic use , Aged, 80 and over , Cyclophosphamide/therapeutic use , Doxorubicin/therapeutic use , Vincristine/therapeutic use , Prednisone/therapeutic use , Telomere/genetics , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Telomere Shortening/genetics , Epigenesis, Genetic/genetics , CpG Islands/genetics
17.
Nat Commun ; 15(1): 4295, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769327

ABSTRACT

Chili pepper (Capsicum) is known for its unique fruit pungency due to the presence of capsaicinoids. The evolutionary history of capsaicinoid biosynthesis and the mechanism of their tissue specificity remain obscure due to the lack of high-quality Capsicum genomes. Here, we report two telomere-to-telomere (T2T) gap-free genomes of C. annuum and its wild nonpungent relative C. rhomboideum to investigate the evolution of fruit pungency in chili peppers. We precisely delineate Capsicum centromeres, which lack high-copy tandem repeats but are extensively invaded by CRM retrotransposons. Through phylogenomic analyses, we estimate the evolutionary timing of capsaicinoid biosynthesis. We reveal disrupted coding and regulatory regions of key biosynthesis genes in nonpungent species. We also find conserved placenta-specific accessible chromatin regions, which likely allow for tissue-specific biosynthetic gene coregulation and capsaicinoid accumulation. These T2T genomic resources will accelerate chili pepper genetic improvement and help to understand Capsicum genome evolution.


Subject(s)
Capsaicin , Capsicum , Evolution, Molecular , Genome, Plant , Phylogeny , Telomere , Capsicum/genetics , Capsicum/metabolism , Capsaicin/metabolism , Telomere/genetics , Telomere/metabolism , Fruit/genetics , Fruit/metabolism , Retroelements/genetics , Gene Expression Regulation, Plant
18.
Nat Struct Mol Biol ; 31(5): 791-800, 2024 May.
Article in English | MEDLINE | ID: mdl-38714889

ABSTRACT

The recognition that DNA can be ADP ribosylated provides an unexpected regulatory level of how ADP-ribosylation contributes to genome stability, epigenetics and immunity. Yet, it remains unknown whether DNA ADP-ribosylation (DNA-ADPr) promotes genome stability and how it is regulated. Here, we show that telomeres are subject to DNA-ADPr catalyzed by PARP1 and removed by TARG1. Mechanistically, we show that DNA-ADPr is coupled to lagging telomere DNA strand synthesis, forming at single-stranded DNA present at unligated Okazaki fragments and on the 3' single-stranded telomere overhang. Persistent DNA-linked ADPr, due to TARG1 deficiency, eventually leads to telomere shortening. Furthermore, using the bacterial DNA ADP-ribosyl-transferase toxin to modify DNA at telomeres directly, we demonstrate that unhydrolyzed DNA-linked ADP-ribose compromises telomere replication and telomere integrity. Thus, by identifying telomeres as chromosomal targets of PARP1 and TARG1-regulated DNA-ADPr, whose deregulation compromises telomere replication and integrity, our study highlights and establishes the critical importance of controlling DNA-ADPr turnover for sustained genome stability.


Subject(s)
ADP-Ribosylation , DNA Replication , DNA , Poly (ADP-Ribose) Polymerase-1 , Telomere , Telomere/metabolism , Telomere/genetics , Poly (ADP-Ribose) Polymerase-1/metabolism , Poly (ADP-Ribose) Polymerase-1/genetics , Humans , DNA/metabolism , Animals , Mice , Adenosine Diphosphate Ribose/metabolism , Genomic Instability , Telomere Shortening
19.
Nutrients ; 16(9)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38732590

ABSTRACT

Nucleotides (NTs), important biomolecules involved in numerous cellular processes, have been proposed as potential candidates for anti-aging interventions. However, whether nucleotides can act as an anti-aging supplement in older adults remains unclear. TALENTs is a randomized, double-blinded, placebo-controlled trial that evaluates the efficacy and safety of NTs as an anti-aging supplement in older adults by exploring the effects of NTs on multiple dimensions of aging in a rigorous scientific setting. Eligible community-dwelling adults aged 60-70 years were randomly assigned equally to two groups: nucleotides intervention group and placebo control group. Comprehensive geriatric health assessments were performed at baseline, 2-months, and 4-months of the intervention. Biological specimens were collected and stored for age-related biomarker testing and multi-omics sequencing. The primary outcome was the change from baseline to 4 months on leukocyte telomere length and DNA methylation age. The secondary aims were the changes in possible mechanisms underlying aging processes (immunity, inflammatory profile, oxidative stress, gene stability, endocrine, metabolism, and cardiovascular function). Other outcomes were changes in physical function, body composition and geriatric health assessment (including sleep quality, cognitive function, fatigue, frailty, and psychology). In the RCT, 301 participants were assessed for eligibility and 122 were enrolled. Participants averaged 65.65 years of age, and were predominately female (67.21%). All baseline characteristics were well-balanced between groups, as expected due to randomization. The majority of participants were pre-frailty and had at least one chronic condition. The mean scores for physical activity, psychological, fatigue and quality of life were within the normal range. However, nearly half of the participants still had room for improvement in cognitive level and sleep quality. This TALENTs trial will represent one of the most comprehensive experimental clinical trials in which supplements are administered to elderly participants. The findings of this study will contribute to our understanding of the anti-aging effects of NTs and provide insights into their potential applications in geriatric healthcare.


Subject(s)
Aging , Longevity , Nucleotides , Humans , Aged , Female , Male , Aging/physiology , Middle Aged , Double-Blind Method , Dietary Supplements , Geriatric Assessment/methods , DNA Methylation/drug effects , Telomere/drug effects , Leukocytes
20.
J Med Virol ; 96(5): e29665, 2024 May.
Article in English | MEDLINE | ID: mdl-38738582

ABSTRACT

The cause of cancer is attributed to the uncontrolled growth and proliferation of cells resulting from genetic changes and alterations in cell behavior, a phenomenon known as epigenetics. Telomeres, protective caps on the ends of chromosomes, regulate both cellular aging and cancer formation. In most cancers, telomerase is upregulated, with the telomerase reverse transcriptase (TERT) enzyme and telomerase RNA component (TERC) RNA element contributing to the maintenance of telomere length. Additionally, it is noteworthy that two viruses, human papillomavirus (HPV) and Epstein-Barr virus (EBV), utilize telomerase for their replication or persistence in infected cells. Also, TERT and TERC may play major roles in cancer not related to telomere biology. They are involved in the regulation of gene expression, signal transduction pathways, cellular metabolism, or even immune response modulation. Furthermore, the crosstalk between TERT, TERC, RNA-binding proteins, and microRNAs contributes to a greater extent to cancer biology. To understand the multifaceted roles played by TERT and TERC in cancer and viral life cycles, and then to develop effective therapeutic strategies against these diseases, are fundamental for this goal. By investigating deeply, the complicated mechanisms and relationships between TERT and TERC, scientists will open the doors to new therapies. In its analysis, the review emphasizes the significance of gaining insight into the multifaceted roles that TERT and TERC play in cancer pathogenesis, as well as their involvement in the viral life cycle for designing effective anticancer therapy approaches.


Subject(s)
Neoplasms , Telomerase , Telomere , Telomerase/metabolism , Telomerase/genetics , Humans , Neoplasms/virology , Neoplasms/genetics , Telomere/metabolism , Herpesvirus 4, Human/genetics , Herpesvirus 4, Human/pathogenicity , Herpesvirus 4, Human/physiology , RNA/metabolism , RNA/genetics
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