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Science (New York, N.Y.) Jun 2024Prion disease is caused by misfolding of the prion protein (PrP) into pathogenic self-propagating conformations, leading to rapid-onset dementia and death. However,...
Prion disease is caused by misfolding of the prion protein (PrP) into pathogenic self-propagating conformations, leading to rapid-onset dementia and death. However, elimination of endogenous PrP halts prion disease progression. In this study, we describe Coupled Histone tail for Autoinhibition Release of Methyltransferase (CHARM), a compact, enzyme-free epigenetic editor capable of silencing transcription through programmable DNA methylation. Using a histone H3 tail-Dnmt3l fusion, CHARM recruits and activates endogenous DNA methyltransferases, thereby reducing transgene size and cytotoxicity. When delivered to the mouse brain by systemic injection of adeno-associated virus (AAV), -targeted CHARM ablates PrP expression across the brain. Furthermore, we have temporally limited editor expression by implementing a kinetically tuned self-silencing approach. CHARM potentially represents a broadly applicable strategy to suppress pathogenic proteins, including those implicated in other neurodegenerative diseases.
Topics: Animals; Dependovirus; Mice; Brain; Prion Proteins; Gene Silencing; Epigenesis, Genetic; Histones; DNA Methylation; DNA (Cytosine-5-)-Methyltransferases; Prion Diseases; Humans; Transgenes
PubMed: 38935715
DOI: 10.1126/science.ado7082 -
Frontiers in Immunology 2024Targeted therapy for Sjögren's syndrome (SS) has become an important focus for clinicians. Multi-omics-wide Mendelian randomization (MR) analyses have provided new...
BACKGROUND
Targeted therapy for Sjögren's syndrome (SS) has become an important focus for clinicians. Multi-omics-wide Mendelian randomization (MR) analyses have provided new ideas for identifying potential drug targets.
METHODS
We conducted summary-data-based Mendelian randomization (SMR) analysis to evaluate therapeutic targets associated with SS by integrating DNA methylation, gene expression and protein quantitative trait loci (mQTL, eQTL, and pQTL, respectively). Genetic associations with SS were derived from the FinnGen study (discovery) and the GWAS catalog (replication). Colocalization analyses were employed to determine whether two potentially relevant phenotypes share the same genetic factors in a given region. Moreover, to delve deeper into potential regulation among DNA methylation, gene expression, and protein abundance, we conducted MR analysis to explore the causal relationship between candidate gene methylation and expression, as well as between gene expression and protein abundance. Drug prediction and molecular docking were further employed to validate the pharmacological activity of the candidate drug targets.
RESULTS
Upon integrating the multi-omics data, we identified three genes associated with SS risk: TNFAIP3, BTN3A1, and PLAU. The methylation of cg22068371 in BTN3A1 was positively associated with protein levels, consistent with the negative effect of cg22068371 methylation on the risk of SS. Additionally, positive correlations were observed between the gene methylation of PLAU (cg04939496) and expression, as well as between expression and protein levels. This consistency elucidates the promotional effects of PLAU on SS risk at the DNA methylation, gene expression, and protein levels. At the protein level, genetically predicted TNFAIP3 (OR 2.47, 95% CI 1.56-3.92) was positively associated with SS risk, while BTN3A1 (OR 2.96E-03, 95% CI 2.63E-04-3.33E-02) was negatively associated with SS risk. Molecular docking showed stable binding for candidate drugs and target proteins.
CONCLUSION
Our study reveals promising therapeutic targets for the treatment of SS, providing valuable insights into targeted therapy for SS. However, further validation through future experiments is warranted.
Topics: Humans; Sjogren's Syndrome; Mendelian Randomization Analysis; Quantitative Trait Loci; DNA Methylation; Genome-Wide Association Study; Molecular Docking Simulation; Genetic Predisposition to Disease; Molecular Targeted Therapy; Polymorphism, Single Nucleotide; Multiomics
PubMed: 38933282
DOI: 10.3389/fimmu.2024.1419363 -
Microorganisms Jun 2024A Gram-positive, rod-shaped, aerobic, motile, and spore-forming bacterium, designated SCL10, was isolated from exposure to Co-60 radiation. In this study, whole-genome...
A Gram-positive, rod-shaped, aerobic, motile, and spore-forming bacterium, designated SCL10, was isolated from exposure to Co-60 radiation. In this study, whole-genome sequencing was performed to identify the strain as and functional characterization, with a focus on stress resistance. The genome of the SCL10 strain was sequenced and assembled, revealing a size of 4,979,182 bp and 5167 coding genes. The genes involved in biological functions were annotated by using the GO, COG, KEGG, NR, and Swiss-Prot databases. The results showed that genes related to alkyl hydroperoxide reductase (, ), DNA-binding proteins from starved cells (), spore and biofilm formation (, 0, ), cold shock-like protein (, ), ATP-dependent chaperone (), and photolyase, small, acid-soluble spore protein (SASP) and DNA repair protein (, ) could explain the stress resistance. These findings suggest that antioxidant activity, sporulation, biofilm formation, and DNA protection may be considered as the main resistance mechanisms under exposure to radiation in the SCL10 strain.
PubMed: 38930550
DOI: 10.3390/microorganisms12061168 -
Medicina (Kaunas, Lithuania) May 2024Primary open angle glaucoma (POAG) is defined as a "genetically complex trait", where modifying factors act on a genetic predisposing background. For the majority of... (Review)
Review
Primary open angle glaucoma (POAG) is defined as a "genetically complex trait", where modifying factors act on a genetic predisposing background. For the majority of glaucomatous conditions, DNA variants are not sufficient to explain pathogenesis. Some genes are clearly underlying the more "Mendelian" forms, while a growing number of related polymorphisms in other genes have been identified in recent years. Environmental, dietary, or biological factors are known to influence the development of the condition, but interactions between these factors and the genetic background are poorly understood. Several studies conducted in recent years have led to evidence that epigenetics, that is, changes in the pattern of gene expression without any changes in the DNA sequence, appear to be the missing link. Different epigenetic mechanisms have been proven to lead to glaucomatous changes in the eye, principally DNA methylation, post-translational histone modification, and RNA-associated gene regulation by non-coding RNAs. The aim of this work is to define the principal epigenetic actors in glaucoma pathogenesis. The identification of such mechanisms could potentially lead to new perspectives on therapeutic strategies.
Topics: Humans; Epigenesis, Genetic; DNA Methylation; Glaucoma, Open-Angle; Glaucoma; Genetic Predisposition to Disease
PubMed: 38929522
DOI: 10.3390/medicina60060905 -
International Journal of Molecular... Jun 2024The tumor microenvironment (TME) is crucial in tumor development, metastasis, and response to immunotherapy. DNA methylation can regulate the TME without altering the...
Identification and Validation of Tumor Microenvironment-Associated Signature in Clear-Cell Renal Cell Carcinoma through Integration of DNA Methylation and Gene Expression.
The tumor microenvironment (TME) is crucial in tumor development, metastasis, and response to immunotherapy. DNA methylation can regulate the TME without altering the DNA sequence. However, research on the methylation-driven TME in clear-cell renal cell carcinoma (ccRCC) is still lacking. In this study, integrated DNA methylation and RNA-seq data were used to explore methylation-driven genes (MDGs). Immune scores were calculated using the ESTIMATE, which was employed to identify TME-related genes. A new signature connected with methylation-regulated TME using univariate, multivariate Cox regression and LASSO regression analyses was developed. This signature consists of four TME-MDGs, including , , , and , which exhibit high methylation and low expression in tumors. Validation was performed using qRT-PCR which confirmed their downregulation in ccRCC clinical samples. Additionally, the signature demonstrated stable predictive performance in different subtypes of ccRCC. Risk scores are positively correlated with TMN stages, immune cell infiltration, tumor mutation burden, and adverse outcomes of immunotherapy. Interestingly, the expression of four TME-MDGs are highly correlated with the sensitivity of first-line drugs in ccRCC treatment, especially pazopanib. Molecular docking indicates a high affinity binding between the proteins and pazopanib. In summary, our study elucidates the comprehensive role of methylation-driven TME in ccRCC, aiding in identifying patients sensitive to immunotherapy and targeted therapy, and providing new therapeutic targets for ccRCC treatment.
Topics: Carcinoma, Renal Cell; Humans; Tumor Microenvironment; DNA Methylation; Kidney Neoplasms; Gene Expression Regulation, Neoplastic; Pyrimidines; Indazoles; Sulfonamides; Biomarkers, Tumor; Female; Molecular Docking Simulation; Gene Expression Profiling; Male
PubMed: 38928496
DOI: 10.3390/ijms25126792 -
International Journal of Molecular... Jun 2024Tissue biopsy remains the standard for diagnosing gastrointestinal stromal tumors (GISTs), although liquid biopsy is emerging as a promising alternative in oncology. In...
Tissue biopsy remains the standard for diagnosing gastrointestinal stromal tumors (GISTs), although liquid biopsy is emerging as a promising alternative in oncology. In this pilot study, we advocate for droplet digital PCR (ddPCR) to diagnose GIST in tissue samples and explore its potential for early diagnosis via liquid biopsy, focusing on the D842V mutation and hypermethylated gene. We utilized ddPCR to analyze the predominant mutation (D842V) in surgical tissue samples from 15 GIST patients, correlating with pathologists' diagnoses. We expanded our analysis to plasma samples to compare DNA alterations between tumor tissue and plasma, also investigating gene hypermethylation. We successfully detected the D842V mutation in GIST tissues by ddPCR. Despite various protocols to enhance mutation detection in early-stage disease, it remained challenging, likely due to the low concentration of DNA in plasma samples. Additionally, the results of Area Under the Curve (AUC) for the hypermethylated gene, analyzing concentration, ratio, and abundance were 0.74 (95% Confidence Interval (CI): 0.52 to 0.97), 0.77 (95% CI: 0.56 to 0.98), and 0.79 (95% CI: 0.59 to 0.99), respectively. As a rare disease, the early detection of GIST through such biomarkers is particularly crucial, offering significant potential to improve patient outcomes.
Topics: Humans; Septins; Gastrointestinal Stromal Tumors; DNA Methylation; Liquid Biopsy; Pilot Projects; Receptor, Platelet-Derived Growth Factor alpha; Female; Male; Middle Aged; Mutation; Polymerase Chain Reaction; Aged; Gastrointestinal Neoplasms; Biomarkers, Tumor; Adult
PubMed: 38928487
DOI: 10.3390/ijms25126783 -
International Journal of Molecular... Jun 2024Bacterial nitroreductase enzymes capable of activating imaging probes and prodrugs are valuable tools for gene-directed enzyme prodrug therapies and targeted cell...
Bacterial nitroreductase enzymes capable of activating imaging probes and prodrugs are valuable tools for gene-directed enzyme prodrug therapies and targeted cell ablation models. We recently engineered a nitroreductase ( NfsB F70A/F108Y) for the substantially enhanced reduction of the 5-nitroimidazole PET-capable probe, SN33623, which permits the theranostic imaging of vectors labeled with oxygen-insensitive bacterial nitroreductases. This mutant enzyme also shows improved activation of the DNA-alkylation prodrugs CB1954 and metronidazole. To elucidate the mechanism behind these enhancements, we resolved the crystal structure of the mutant enzyme to 1.98 Å and compared it to the wild-type enzyme. Structural analysis revealed an expanded substrate access channel and new hydrogen bonding interactions. Additionally, computational modeling of SN33623, CB1954, and metronidazole binding in the active sites of both the mutant and wild-type enzymes revealed key differences in substrate orientations and interactions, with improvements in activity being mirrored by reduced distances between the N5-H of isoalloxazine and the substrate nitro group oxygen in the mutant models. These findings deepen our understanding of nitroreductase substrate specificity and catalytic mechanisms and have potential implications for developing more effective theranostic imaging strategies in cancer treatment.
Topics: Nitroreductases; Nitroimidazoles; Metronidazole; Prodrugs; Escherichia coli Proteins; Positron-Emission Tomography; Escherichia coli; Catalytic Domain; Protein Engineering; Models, Molecular; Aziridines
PubMed: 38928299
DOI: 10.3390/ijms25126593 -
International Journal of Molecular... Jun 2024Mutations affecting codon 172 of the isocitrate dehydrogenase 2 () gene define a subgroup of sinonasal undifferentiated carcinomas (SNUCs) with a relatively favorable...
Mutations affecting codon 172 of the isocitrate dehydrogenase 2 () gene define a subgroup of sinonasal undifferentiated carcinomas (SNUCs) with a relatively favorable prognosis and a globally hypermethylated phenotype. They are also recurrent (along with mutations) in gliomas, acute myeloid leukemia, and intrahepatic cholangiocarcinoma. Commonly reported mutations, all associated with aberrant IDH2 enzymatic activity, include R172K, R172S, R172T, R172G, and R172M. We present a case of SNUC with a never-before-described mutation, R172A. Our report compares the methylation pattern of our sample to other cases from the Gene Expression Omnibus database. Hierarchical clustering suggests a strong association between our sample and other IDH-mutant SNUCs and a clear distinction between sinonasal normal tissues and tumors. Principal component analysis (PCA), using 100 principal components explaining 94.5% of the variance, showed the position of our sample to be within 1.02 standard deviation of the other IDH-mutant SNUCs. A molecular modeling analysis of the R172A versus other R172 variants provides a structural explanation to how they affect the protein active site. Our findings thus suggest that the R172A mutation in confers a gain of function similar to other R172 mutations in , resulting in a similar hypermethylated profile.
Topics: Humans; Isocitrate Dehydrogenase; DNA Methylation; Carcinoma; Mutation; Maxillary Sinus Neoplasms; Male; Middle Aged; Female; Aged
PubMed: 38928223
DOI: 10.3390/ijms25126518 -
International Journal of Molecular... Jun 2024Hypoxia-inducible factor 1-alpha (HIF1A) is a key transcription factor aiding tumor cells' adaptation to hypoxia, regulated by the prolyl hydroxylase family (EGLN1-3) by...
Hypoxia-inducible factor 1-alpha (HIF1A) is a key transcription factor aiding tumor cells' adaptation to hypoxia, regulated by the prolyl hydroxylase family (EGLN1-3) by directing toward degradation pathways. DNA methylation potentially influences EGLN and HIF1A levels, impacting cellular responses to hypoxia. We examined 96 HNSCC patients and three cell lines, analyzing gene expression of , , , , and at the mRNA level and EGLN1 protein levels. Methylation levels of and were assessed through high-resolution melting analysis. Bioinformatics tools were employed to characterize associations between and expression and methylation. We found significantly higher mRNA levels of , , , , and ( = 0.021; < 0.0001; < 0.0001; = 0.004, and < 0.0001, respectively) genes in tumor tissues compared to normal ones and downregulation of the mRNA level in tumor tissues ( = 0.0013). In HNSCC patients with hypermethylation of in normal tissue, we noted a reduction in mRNA levels compared to tumor tissue ( = 0.04). In conclusion, the differential expression of and genes in HNSCC tumors compared to normal tissues influences patients' overall survival, highlighting their role in tumor development. Moreover, DNA methylation could be responsible for suppression in the normal tissues of HNSCC patients.
Topics: Humans; DNA Methylation; Hypoxia-Inducible Factor 1, alpha Subunit; Squamous Cell Carcinoma of Head and Neck; Female; Head and Neck Neoplasms; Male; Gene Expression Regulation, Neoplastic; Cell Line, Tumor; Hypoxia-Inducible Factor-Proline Dioxygenases; Middle Aged; Prolyl Hydroxylases; Aged; Carcinogenesis; Adult
PubMed: 38928200
DOI: 10.3390/ijms25126495 -
International Journal of Molecular... Jun 2024The placenta is a crucial determinant of fetal survival, growth, and development. Deficiency in placental development directly causes intrauterine growth retardation...
The placenta is a crucial determinant of fetal survival, growth, and development. Deficiency in placental development directly causes intrauterine growth retardation (IUGR). IUGR can lead to fetal growth restriction and an increase in the mortality rate. The genetic mechanisms underlying IUGR development, however, remain unclear. In the present study, we integrated whole-genome DNA methylation and transcriptomic analyses to determine distinct gene expression patterns in various placental tissues to identify pivotal genes that are implicated with IUGR development. By performing RNA-sequencing analysis, 1487 differentially expressed genes (DEGs), with 737 upregulated and 750 downregulated genes, were identified in IUGR pigs (H_IUGR) compared with that in normal birth weight pigs (N_IUGR) ( < 0.05); furthermore, 77 miRNAs, 1331 lncRNAs, and 61 circRNAs were differentially expressed. The protein-protein interaction network analysis revealed that among these DEGs, the genes GNGT1, ANXA1, and CDC20 related to cellular developmental processes and blood vessel development were the key genes associated with the development of IUGR. A total of 495,870 differentially methylated regions were identified between the N_IUGR and H_IUGR groups, which included 25,053 differentially methylated genes (DMEs); moreover, the overall methylation level was higher in the H_IUGR group than in the N_IUGR group. Combined analysis showed an inverse correlation between methylation levels and gene expression. A total of 1375 genes involved in developmental processes, tissue development, and immune system regulation exhibited methylation differences in gene expression levels in the promoter regions and gene ontology regions. Five genes, namely, ANXA1, ADM, NRP2, SHH, and SMAD1, with high methylation levels were identified as potential contributors to IUGR development. These findings provide valuable insights that DNA methylation plays a crucial role in the epigenetic regulation of gene expression and mammalian development and that DNA-hypermethylated genes contribute to IUGR development in Rongchang pigs.
Topics: Animals; Fetal Growth Retardation; DNA Methylation; Swine; Female; Pregnancy; Placenta; Gene Expression Profiling; Protein Interaction Maps; Epigenesis, Genetic; MicroRNAs; Transcriptome; Gene Regulatory Networks
PubMed: 38928167
DOI: 10.3390/ijms25126462