N^(6)-methyladenosine RNA methylation,an essential post-transcriptional modification,dynamically regulates RNA metabolism and plays a crucial role in neuronal function.Growing evidence suggests that dysregulated N^(6)...N^(6)-methyladenosine RNA methylation,an essential post-transcriptional modification,dynamically regulates RNA metabolism and plays a crucial role in neuronal function.Growing evidence suggests that dysregulated N^(6)-methyladenosine modification contributes to the pathogenesis of neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease,multiple sclerosis,and amyotrophic lateral sclerosis.However,the precise mechanisms by which N^(6)-methyladenosine modification influences these conditions remain unclear.This review summarizes the role of m6A modification and its associated regulators in neurodegeneration,focusing on their involvement in key pathological processes.In Alzheimer’s disease,m6A modification contributes to synaptic dysfunction,mitochondrial damage,and neuronal apoptosis.Evidence from APP/PS1,5xFAD,tau transgenic,and Drosophila models demonstrates that regulators such as methyltransferase-like 3 and fat mass and obesity-associated protein influence Alzheimer’s disease progression through neuroinflammation,circular RNAs dysregulation,and autophagy-related mechanisms.In Parkinson’s disease,altered N^(6)-methyladenosine regulator expression affects dopaminergic neuron survival and stress responses by modulating mRNA stability and autophagy-related lncRNAs.In multiple sclerosis and amyotrophic lateral sclerosis,N^(6)-methyladenosine affects immune activation,myelin repair,and the regulation of disease-associated genes such as TDP-43.Beyond N^(6)-methyladenosine,other RNA methylation modifications-such as m1A,m5C,m7G,uracil,and pseudouridine-are implicated in neurodegenerative diseases through their regulation of mitochondrial function,RNA metabolism,and neuronal stress responses.Additionally,N^(6)-methyladenosine exhibits cell type-specific functions:in microglia,it regulates inflammatory activation and phagocytic function;in astrocytes,it modulates metabolic homeostasis and glutamate-associated neurotoxicity;in neurons,it affects synaptic function and neurodegeneration-related gene expression;and in adult neural stem cells,it controls differentiation,neurogenesis,and cognitive plasticity.Recently,several small-molecule inhibitors targeting methyltransferase-like 3 or fat mass and obesity-associated protein have been developed to modulate N^(6)-methyladenosine modification,providing new opportunities for disease intervention,with the targeting of N⁶-methyladenosine-related pathways emerging as a promising therapeutic strategy.However,challenges persist in optimizing the specificity and delivery of these therapeutic approaches.展开更多
The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsor...The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications.展开更多
DNA methylation is an important promising biomarker for cancer diagnosis and monitoring.Therefore,the assessment of DNA methylation levels is helpful for the prognosis and diagnosis of cancer.However,it is still a hug...DNA methylation is an important promising biomarker for cancer diagnosis and monitoring.Therefore,the assessment of DNA methylation levels is helpful for the prognosis and diagnosis of cancer.However,it is still a huge challenge to sensitively and accurately quantify the levels of DNA methylation in clinical sample.In this work,we proposed a protospacer adjacent motif(PAM)-free mediated CRISPR-Cas12a ultra-sensitive and quantitative DNA methylation detection method.Through recognizing the ds DNA with toehold region,CRISPR-Cas12a not only got rid of the limitation of PAM,but also improved its distinction ability for single Cp G site methylation,nearly 5-fold that of conventional PAM-containing ds DNA.We further introduced assist-strand and design an artificial mismatch to greatly improve the ability to distinguish single Cp G methylation site.Our results showed that the discrimination factor was >200.Then,we constructed toe-ds DNA by using “heating and freezing”,which made our method universally applicable and feasible.In addition,we greatly simplified the difficulty of primer design.Our method detected four highly methylated genes acyl carrier protein(ACP),CLV3/ESR-related(CLE),Disabled(DAB) and Homeobox(HOX) with a detection limit of 0.01 % and excellent linearity in DNA methylation standards.Then,we verified the clinical utility of this method in 29 hepatocellular carcinomas,11 ovarian cancers and4 health people.In conclusion,we have successfully constructed a PAM-free CRISPR-Cas12a DNA methylation quantification method,which achieves high congruence in sensitivity,specificity and universality,fully demonstrating its significant clinical application value.展开更多
Fig(Ficus carica L.)with purple-red peel cultivars are popular among consumers and exhibit better storability.While DNA methylation influences fruit ripening and color development,its specific role in fig fruit remain...Fig(Ficus carica L.)with purple-red peel cultivars are popular among consumers and exhibit better storability.While DNA methylation influences fruit ripening and color development,its specific role in fig fruit remains unclear.This study explores the impact of DNA methylation on the fig peel coloration.Enzymatic colorimetric detection revealed that the level of‘Purple Peel’fig DNA methylation decreases with fig fruit ripening and coloring.Treatment of young fruit with the DNA-methylation inhibitor azacytidine induced peel coloration,suggesting that a decrease in DNA-methylation level promotes fig peel coloration.Seven members of DNA methyltransferases and three members of DNA demethylases were identified from a high-level fig genome,highlighting FcMET1 and FcDRM2 as stable proteins,ensuring functional expression.Reference to the Arabidopsis protein interaction network map predicted that FcMET1 is in a central position,suggesting a crucial regulatory role in multiple biological processes.Correlation analysis revealed a positive correlation between FcMET1 expression during peel development and the level of total DNA methylation.Weighted gene co-expression network analysis identified co-expression of FcMET1 with the color-related transcription factors MYB,bHLH and WD40,as well as with eight structural genes in the flavonoid-biosynthesis pathway.The expression of FcUFGT3 was negatively correlated with that of FcMET1.McrBC-PCR and Bisulfite Sequencing detection showed that a low methylation level of the FcUFGT3 promoter corresponds with its high expression in colored fig.This investigation of the mechanism of DNA methylation provides a theoretical basis for understanding the role of DNA-methylation modifications in fig ripening and coloring.展开更多
Reader proteins that bind specific methyllysine are important to biological functions of lysine methylation,but readers of many methyllysine sites are still unknown.Therefore,development of covalent probes is importan...Reader proteins that bind specific methyllysine are important to biological functions of lysine methylation,but readers of many methyllysine sites are still unknown.Therefore,development of covalent probes is important to identify readers from cell samples so as to understand biological roles of lysine methylation.Generally,readers bind methyllysine via aromatic cages that contain tryptophan,tyrosine and phenylalanine,that offer a unique motif for selective crosslinking.We recently reported a site-selective tryptophan crosslinking strategy based on dimethylsulfonium that mimics dimethyllysine to crosslink tryptophan in aromatic cages of readers.Since tyrosine is a key residue for binding affinity to methyllysine,especially some readers that do not contain tryptophan residues in the binding pocket.Here we developed strategies of site-selective crosslinking to tyrosine.Ultraviolet(UV)source was applied to excite tyrosine at neutral pH or phenoxide at basic p H,and subsequent single-electron transfer(SET)from Tyr*to sulfonium inside the binding pocket enables selective crosslinking.In consequence,methyllysine readers with tyrosine-containing aromatic cages could be selectively crosslinked by site-specific sulfonium peptide probes.In addition,we expanded substrates from aromatic cages to tyrosine residues of proximate contact with sulfonium probes.The pair of LgBiT and SmBiT exhibited orthogonal crosslinking in complicated cell samples.As a result,we may expand sulfonium tools to target local tyrosine in future investigations.展开更多
Detecting lung cancer early is crucial for improving survival rates,yet it remains a significant challenge due to many cases being diagnosed at advanced stages.This review aims to provide advances in epigenetics which...Detecting lung cancer early is crucial for improving survival rates,yet it remains a significant challenge due to many cases being diagnosed at advanced stages.This review aims to provide advances in epigenetics which have highlighted DNA methylation patterns as promising biomarkers for early detection,prognosis,and treatment response in lung cancer.Techniques like bisulfite conversion followed by PCR,digital droplet polymerase chain reaction,and next-generation sequencing are commonly used for detecting these methylation patterns,which occur early in the cancer development process and can be detected in non-invasive samples like blood and sputum.Key genes such as SHOX2 and RASSF1A have demonstrated high sensitivity and specificity in clinical studies,making them crucial for diagnostic purposes.However,several challenges remain to be overcome before these biomarkers can be widely adopted for use in clinical practice.Standardizing the assays and validating their effectiveness are critical steps.Additionally,integrating methylation biomarkers with existing diagnostic tools could significantly enhance the accuracy of lung cancer detection,providing a more comprehensive diagnostic approach.Although progress has been made in understanding and utilizing DNA methylation patterns for lung cancer detection,more research and extensive clinical trials are necessary to fully harness their potential.These efforts will help establish the robustness of methylation patterns as biomarkers and therapeutic targets,ultimately leading to better prevention,diagnosis,and treatment strategies for lung cancer.In conclusion,DNA methylation states represent a promising avenue for advancing early detection,accurate diagnosis,and management of lung cancer.展开更多
The methylation of DNA is a prevalent epigenetic modification that plays a crucial role in the pathological progression of ocular diseases.DNA methylation can regulate gene expression,thereby affecting cell function a...The methylation of DNA is a prevalent epigenetic modification that plays a crucial role in the pathological progression of ocular diseases.DNA methylation can regulate gene expression,thereby affecting cell function and signal transduction.Ophthalmic diseases are a kind of complex diseases,and their pathogenesis involves many factors such as genetic,environmental and individual differences.In addition,inflammation,oxidative stress and lipid metabolism,which abnormal DNA methylation is closely related to,are also considered to be major factors in eye diseases.The current understanding of DNA methylation in eye diseases is becoming more complex and comprehensive.In addition to the simple suppression of gene expression by hypermethylation,factors such as hypomethylation or demethylation,DNA methylation in non-promoter regions,interactions with other epigenetic modifications,and dynamic changes in DNA methylation must also be considered.Interestingly,although some genes are at abnormal methylation levels,their expression is not significantly changed,which indirectly reflects the complexity of gene regulation.This review aims to summarize and compare some relevant studies,and provide with new ideas and methods for the prevention and treatment of different eye diseases,such as glaucoma,retinoblastoma,and diabetic retinopathy.展开更多
Illegal hunting and trafficking of wildlife and their derivatives extort unprecedented population decline of relatively many species pushing them towards extinction.Notwithstanding contemporary counteracting intervent...Illegal hunting and trafficking of wildlife and their derivatives extort unprecedented population decline of relatively many species pushing them towards extinction.Notwithstanding contemporary counteracting interventions at international,regional,national and local levels,wildlife farming is advocated as an alternative approach to minimize pressure on wild populations.For wildlife farming to be an effective conservation tool,the integration of wildlife forensics is inevitable to allow distinction between captive-bred and wild-caught species.To this end,we analyzed methylation rates of skeletal muscle samples(pectoralis major,triceps brachii,gastrocnemius,biceps femoris,and neck muscles)from 60 captive-bred and 30 wild-caught Common Pheasant.A total of 13,507 differentially methylated regions were identified between five wild-caught and five captive-bred individuals through whole-genome methylation sequencing(WGBS).Based on the selected five methylation sites,LOC116231076,LOC116242223,ATAD2B,EGFL6,and HS2ST,quantitative detection technique was developed using methylation-sensitive high-resolution melting curve(MS-HRM)to measure methylation rates.The results showed significant differences in methylation rates at all differential sites between wild-caught and captive-bred individuals(|t|=0.67–33.10,P=0.000–0.042).The discrimination accuracy rate of each locus was highest in the gastrocnemius muscle and lowest in the neck muscle.The discrimination accuracy rate on LOC116231076,LOC116242223,ATAD2B,EGFL6,and HS2ST methylation sites for gastrocnemius muscle was 64.98%,100.00%,68.54%,63.79%,and 63.70%,respectively;and for neck muscle it was 67.42%,68.06%,83.61%,65.04%,and68.85%,respectively.The united discrimination accuracy rate of the five loci were 100.00%for gastrocnemius muscle,99.78%for biceps femoris muscle,97.52%for pectoralis major muscle,93.96%for triceps brachii muscle,and 91.63%for neck muscle,respectively.The panel also revealed excellent repeatability,reproducibility,sensitivity and universality to mammals and avian species.This study establishes an effective,accurate and low-cost identification technology for the identification of wild and farmed Common Pheasant,and also provides a reference for the development of identification methods for other species.展开更多
BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this ...BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this disease.AIM To explore the mechanism of miR-125a-5p in the pathogenesis of GC.METHODS The expression levels of miR-125a-5p,SERPINE1 and DNMT1 in GC cells and tissues were detected by real-time polymerase chain reaction(PCR)and Western blotting.Methylation-specific PCR was used to detect the level of miR-125a-5p methylation.A cell counting kit 8 assay,scratch test,and a Transwell assay were performed to detect the proliferation,migration,and invasiveness of HGC27 cells,respectively.The expression of the epithelial mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin and vimentin in HGC27 cells was detected by Western blotting,while the expression of vimentin was detected by immunofluorescence.RESULTS This study revealed that miR-125a-5p was expressed at low levels in GC clinical samples and cells and that miR-125a-5p overexpression inhibited the proliferation,migration,invasiveness and EMT of GC cells.Mechanistically,miR-125a-5p can reduce GC cell proliferation,promote E-cadherin expression,inhibit N-cadherin and vimentin expression,and reduce the EMT of GC cells,thus constraining GC cells to a certain extent.Moreover,DNMT1 inhibited miR-125a-5p expression by increasing the methylation of the miR-125a-5p promoter,thereby promoting the expression of SERPINE1,which acts together with miR-125a-5p to exert antagonistic effects on GC.CONCLUSION Our study revealed that DNMT1 promoted SERPINE1 protein expression by inducing miR-125a-5p methylation,which led to the proliferation,migration and occurrence of EMT in GC cells.展开更多
BACKGROUND Epigenetic regulation of leptin(LEP)plays a critical role in metabolic disorders,yet its promoter methylation patterns in lean diabetic populations remain poorly characterized.Emerging evidence suggests DNA...BACKGROUND Epigenetic regulation of leptin(LEP)plays a critical role in metabolic disorders,yet its promoter methylation patterns in lean diabetic populations remain poorly characterized.Emerging evidence suggests DNA methylation may precede clinical hyperglycemia,offering potential for early risk stratification.While obesity-associated LEP methylation is well-studied,lean Asian populations who exhibit high diabetes prevalence despite lower adiposity,represent an underexplored cohort.This study hypothesizes that LEP promoter methylation in peripheral leukocytes decreases progressively from normoglycemia to prediabetes and type 2 diabetes mellitus(T2DM),correlating inversely with serum LEP levels in lean Chinese adults[body mass index(BMI)<24 kg/m^(2)].AIM To investigate LEP promoter methylation status and its association with serum LEP levels across glycemic states in lean Chinese adults.METHODS We enrolled 392 participants including 120 normoglycemic controls,94 prediabetes[44 impaired fasting glucose(IFG)/50 impaired glucose tolerance(IGT)],178 T2DM aged 40-60 years with BMI<24 kg/m^(2).Genomic DNA from peripheral leukocytes underwent bisulfite conversion followed by methylation-specific PCR to assess CpG methylation in the LEP promoter.Serum LEP was quantified via enzyme-linked immunosorbent assay,with other parameters measured through standard assays.Statistical analyses included analysis of variance,χ²tests,and Pearson correlation(Bonferroni-corrected P value).RESULTS Methylation frequencies declined progressively:59.2%(controls)reduced to 43.6%(prediabetes;IFG:38.6%,IGT:48%)reduced to 31.5%(T2DM)(all P<0.05 vs controls;T2DM vs IGT:P=0.030).Serum LEP levels increased significantly in T2DM(16.94±4.19μg/L)vs controls(11.33±3.10μg/L;P=0.002),with intermediate values in prediabetes(IFG:13.79±3.32μg/L;IGT:12.62±4.81μg/L).A near-perfect inverse correlation between methylation and LEP levels was observed(r=-0.95,95%CI:-0.97 to-0.92,P<0.001),persisting after adjusting for age and BMI(β=-0.91,P<0.001).CONCLUSION LEP promoter hypomethylation parallels worsening glycemic status in lean Chinese adults,suggesting its potential as a blood-based epigenetic biomarker for diabetes progression,pending validation in longitudinal cohorts.展开更多
Cyclic volatile methyl siloxanes(cVMSs)are widely used in industrial and consumer products because of their thermal stability,low reactivity,and reduced surface tension[1].Their extensive use has resulted in environme...Cyclic volatile methyl siloxanes(cVMSs)are widely used in industrial and consumer products because of their thermal stability,low reactivity,and reduced surface tension[1].Their extensive use has resulted in environmental pollution globally.Recognized as very persistent and very bioaccumulative(vPvB),compounds such as octamethylcyclotetrasiloxane(D4),decamethylcyclopentasiloxane(D5),and dodecamethylcyclohexasiloxane(D6)are regulated in the European Union[2]and are monitored worldwide.展开更多
In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels...In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels at CGIs remains largely elusive.KDM2 proteins(KDM2A and KDM2B)are H3K36me2 demethylases known to bind specifically at CGIs.Here,we report that depletion of each or both KDM2 proteins,or mutation of all their JmjC domains that harbor the H3K36me2 demethylation activity,leads to an increase in DNA methylation at selective CGIs.The Kdm2a/2b double knockout shows a stronger increase in DNA methylation compared with the single mutant of Kdm2a or Kdm2b,indicating that KDM2A and KDM2B redundantly regulate DNA methylation at CGIs.In addition,the increase of CGI DNA methylation upon mutations of KDM2 proteins is associated with the chromatin environment.Our findings reveal that KDM2A and KDM2B function redundantly in regulating DNA methylation at a subset of CGIs in an H3K36me2 demethylation-dependent manner.展开更多
DNA methylation is a critical epigenetic regulator in the occurrence and development of diseases and is closely related to various functional responses in relation to spinal cord injury.To investigate the role of DNA ...DNA methylation is a critical epigenetic regulator in the occurrence and development of diseases and is closely related to various functional responses in relation to spinal cord injury.To investigate the role of DNA methylation in spinal cord injury,we constructed a library with reduced-representation bisulfite sequencing data obtained at various time points(day 0-42)after spinal cord injury in mice.Global DNA methylation levels,specifically non-CpG(CHG and CHH)methylation levels,decreased modestly following spinal cord injury.Stages post-spinal cord injury were classified as early(day 0-3),intermediate(day7-14),and late(day 28-42)based on similarity and hie rarchical cluste ring of global DNA methylation patterns.The non-CpG methylation level,which included CHG and CHH methylation levels,was markedly reduced despite accounting for a minor proportion of total methylation abundance.At multiple genomic sites,including the 5’untranslated regions,promoter,exon,intron,and 3’untranslated regions,the non-CpG methylation level was markedly decreased following spinal cord injury,whereas the CpG methylation level remained unchanged at these locations.Approximately one-half of the differentially methylated regions were located in intergenic areas;the other differentially methylated regions in both CpG and non-CpG regions were cluste red in intron regions,where the DNA methylation level was highest.The function of genes associated with differentially methylated regions in promoter regions was also investigated.From Gene Ontology analysis results,DNA methylation was implicated in a number of essential functional responses to spinal cord injury,including neuronal synaptic connection creation and axon regeneration.Notably,neither CpG methylation nor non-CpG methylation was implicated in the functional response of glial or inflammatory cells.In summary,our work elucidated the dynamic pattern of DNA methylation in the spinal co rd following injury and identified reduced nonCpG methylation as an epigenetic target after spinal cord injury in mice.展开更多
Colitis-associated colorectal cancer(CAC),a serious complication of ulcerative colitis(UC),is associated with a poor prognosis.The vitamin D receptor(VDR)is recognized for its protective role in UC and CAC through the...Colitis-associated colorectal cancer(CAC),a serious complication of ulcerative colitis(UC),is associated with a poor prognosis.The vitamin D receptor(VDR)is recognized for its protective role in UC and CAC through the maintenance of intestinal barrier integrity and the regulation of inflammation.This study demonstrates a significant reduction in m^(6)A-related genes,particularly methyltransferase like 14(METTL14),in UC and CAC patients and identifies an association between METTL14 and VDR.In the azoxymethane(AOM)/dextran sodium sulfate(DSS)-induced mousemodel,vitamin D treatment increases METTL14 expression and reduces tumorburden,while Vdr-knockout mice exhibit lower METTL14 levels and increased tumorigenesis.In vitro,the VDR agonist calcipotriol upregulates METTL14 in NCM460 cells,with this effect attenuated by VDR knockdown.VDRknockdown inDLD-1colon cancer cellsdecreases METTL14 expressionand promotes proliferation,which is reversed by METTL14 overexpression.Mechanistic studies reveal that VDR regulates METTL14 expression via promoter binding,modulating key target genes such as SOX4,DROSH,and PHLPP2.This study highlights the role of the VDR-METTL14 axis as a protective mechanism in CAC and suggests its potential as a therapeutic target for preventing and treating CAC.展开更多
Homoisoflavonoids are in the subclass of the larger family of flavonoids having one more alkyl carbon than flavonoids. Among them, 8-C-Methylated homoisoflavones have not been extensively studied for synthesis and bio...Homoisoflavonoids are in the subclass of the larger family of flavonoids having one more alkyl carbon than flavonoids. Among them, 8-C-Methylated homoisoflavones have not been extensively studied for synthesis and biological evaluation. Author’s current objective is to synthesize 8-C-Methylated homoisoflavones by the reaction of 3-C-methylated dihydrochalcones with N,N’-dimethyl (chloromethylene) ammonium chloride generated in situ from DMF and PCl<sub>5</sub> for one carbon extension at about room temperature. The 3-C-methylated dihydrochalcones were synthesized by the reduction of 3-C-methylated chalcones, which were prepared from 3-C-methylated acetophenones and aromatic aldehydes in the presence of base. All the synthesized novel homoisoflavones’s structures were characterized by NMR and Tandem Mass Spectrometry.展开更多
Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environme...Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environmental toxin that causes Parkinson's disease.However,the mechanism by which Sal mediates dopaminergic neuronal death remains unclear.In this study,we found that Sal significantly enhanced the global level of N~6-methyladenosine(m~6A)RNA methylation in PC12 cells,mainly by inducing the downregulation of the expression of m~6A demethylases fat mass and obesity-associated protein(FTO)and alk B homolog 5(ALKBH5).RNA sequencing analysis showed that Sal downregulated the Hippo signaling pathway.The m~6A reader YTH domain-containing family protein 2(YTHDF2)promoted the degradation of m~6A-containing Yes-associated protein 1(YAP1)mRNA,which is a downstream key effector in the Hippo signaling pathway.Additionally,downregulation of YAP1 promoted autophagy,indicating that the mutual regulation between YAP1 and autophagy can lead to neurotoxicity.These findings reveal the role of Sal on m~6A RNA methylation and suggest that Sal may act as an RNA methylation inducer mediating dopaminergic neuronal death through YAP1 and autophagy.Our results provide greater insights into the neurotoxic effects of catechol isoquinolines compared with other studies and may be a reference for assessing the involvement of RNA methylation in the pathogenesis of Parkinson's disease.展开更多
RNA methylation modifications have been found for decades of years, which occur at different RNA types of numerous species, and their distribution is species-specific. However, people rarely know their biological func...RNA methylation modifications have been found for decades of years, which occur at different RNA types of numerous species, and their distribution is species-specific. However, people rarely know their biological functions. There are several identified methylation modifications in eukaryotic messenger RNA （mRNA）, such as NT-methylguanosine （mVG） at the cap, Nr-methyl-2＇-O-methyladenosine （m6Am）, 2＇-O-methylation （Nm） within the cap and the internal positions, and internal N6-methyladenosine （m6A） and 5-methylcytosine （mSC）. Among them, mTG cap was studied more clearly and found to have vital roles in several important mRNA processes like mRNA translation, stability and nuclear export, m6A as the most abundant modification in mRNA was found in the 1970s and has been proposed to function in mRNA splicing, translation, stability, transport and so on. mrA has been discovered as the first RNA reversible modification which is demethylated directly by human fat mass and obesity associated protein （FRO） and its homolog protein, alkylation repair ho- molog 5 （ALKBH5）. b-TO has a special demethylation mechanism that demethylases m6A to A through two over-oxidative intermediate states： N6-hydroxymethyladenosine （hm6A） and Nr-formyladenosine （frA）. The two newly discovered m6A demethylases, bTO and ALKBH5, significantly control energy homeostasis and spermatogenesis, respectively, indicating that the dynamic and reversible mrA, analogous to DNA and histone modifications, plays broad roles in biological kingdoms and brings us an emerging field ＂RNA Epige- netics＂. 5-methylcytosine （5mC） as an epigenetic mark in DNA has been studied widely, but mSC in mRNA is seldom explored. The bisulfide sequencing showed mSC is another abundant modification in mRNA, suggesting that it might be another RNA epigenetic mark. This review focuses on the main methylation modifications in mRNA to describe their formation, distribution, function and demethylation from the current knowledge and to provide future 19erspectives on functional studies.展开更多
Pancreatic cancer(PanCa)presents a catastrophic disease with poor overall survival at advanced stages,with immediate requirement of new and effective treatment options.Besides genetic mutations,epigenetic dysregulatio...Pancreatic cancer(PanCa)presents a catastrophic disease with poor overall survival at advanced stages,with immediate requirement of new and effective treatment options.Besides genetic mutations,epigenetic dysregulation of signaling pathway-associated enriched genes are considered as novel therapeutic target.Mechanisms beneath the deoxyribonucleic acid methylation and its utility in developing of epi-drugs in PanCa are under trails.Combinations of epigenetic medicines with conventional cytotoxic treatments or targeted therapy are promising options to improving the dismal response and survival rate of PanCa patients.Recent studies have identified potentially valid pathways that support the prediction that future PanCa clinical trials will include vigorous testing of epigenomic therapies.Epigenetics thus promises to generate a significant amount of new knowledge of biological and medical importance.Our review could identify various components of epigenetic mechanisms known to be involved in the initiation and development of pancreatic ductal adenocarcinoma and related precancerous lesions,and novel pharmacological strategies that target these components could potentially lead to breakthroughs.We aim to highlight the possibilities that exist and the potential therapeutic interventions.展开更多
BACKGROUND Cholangiocarcinoma(CCA),also known as bile duct cancer,is a devastating malignancy primarily affecting the biliary tract.AIM To assess their performance in clinical diagnosis and monitoring of CCA,plasma me...BACKGROUND Cholangiocarcinoma(CCA),also known as bile duct cancer,is a devastating malignancy primarily affecting the biliary tract.AIM To assess their performance in clinical diagnosis and monitoring of CCA,plasma methylation and circulating tumor cells were detected.METHODS Plasma samples were collected from Hubei Cancer Hospital(n=156).Plasma DNA was tested to detect SHOX2,HOXA9,SEPTIN9,and RASSF1A methylation using TaqMan PCR.Circulating tumor cells(CTCs)were detected in the peripheral blood of patients using the United States Food and Drug Administration-approved cell search system before and after clinical therapy.The CCA diagnostic value was estimated using the area under the curve.The independent prognosis risk factors for patients with CCA were estimated using Cox and logistic regression analyses.RESULTS The sensitivity and specificity of the four DNA plasma methylations exhibited 64.74%sensitivity and 93.88%specificity for detecting CCA.The receiver operating characteristic curve of the combined value for CCA diagnosis in plasma was 0.828±0.032.RASSF1A plasma methylation was related to the prognosis of patients with CCA.We determined the prognostic hazard ratio for CCA using CTC count,tumor stage,methylation,and carbohydrate antigen 19-9 levels as key factors.Our overall survival nomogram achieved a C-index of 0.705(0.605-0.805).CONCLUSION SHOX2,HOXA9,SEPTIN9,and RASSF1A plasma methylation demonstrated increased sensitivity for diagnosing CCA.RASSF1A plasma methylation and CTCs were valuable predictors to assess CCA prognosis and recurrence.展开更多
DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Ca...DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Camellia sinensis).In this study,we combined the methylome,transcriptome,and metabolome to investigate the dynamic changes in DNA methylation and its potential regulatory roles in secondary metabolite biosynthesis.In this study,the level of genomic DNA methylation increased as leaf development progressed from tender to old leaf.It additionally exhibited a similar distribution across the genomic background at the two distinct developmental stages studied.Notably,integrated analysis of transcriptomic and methylomic data showed that DNA hypermethylation primarily occurred in genes of the phenylpropanoid,flavonoid,and terpenoid biosynthesis pathways.The effect of methylation on transcription of these secondary metabolite biosynthesis genes was dependent on the location of methylation(i.e.,in the promoter,gene or intergenic regions)and the sequence context(i.e.,CpG,CHG,or CHH).Changes in the content of catechins and terpenoids were consistent with the changes in gene transcription and the methylation state of structural genes,such as serine carboxypeptidase-like acyltransferases 1A(SCPL1A),leucoanthocyanidin reductase(LAR),and nerolidol synthase(NES).Our study provides valuable information for dissecting the effects of DNA methylation on regulation of genes involved in secondary metabolism during tea leaf development.展开更多
基金supported by the National Nature Science Foundation of China(General Program),Nos.82271237,82071218(both to JC),and 82230042(to ZY)the Foundation of Key Laboratory of Neurology,Hebei Medical University,Ministry of Education,China,No.2023001(to JC).
文摘N^(6)-methyladenosine RNA methylation,an essential post-transcriptional modification,dynamically regulates RNA metabolism and plays a crucial role in neuronal function.Growing evidence suggests that dysregulated N^(6)-methyladenosine modification contributes to the pathogenesis of neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease,multiple sclerosis,and amyotrophic lateral sclerosis.However,the precise mechanisms by which N^(6)-methyladenosine modification influences these conditions remain unclear.This review summarizes the role of m6A modification and its associated regulators in neurodegeneration,focusing on their involvement in key pathological processes.In Alzheimer’s disease,m6A modification contributes to synaptic dysfunction,mitochondrial damage,and neuronal apoptosis.Evidence from APP/PS1,5xFAD,tau transgenic,and Drosophila models demonstrates that regulators such as methyltransferase-like 3 and fat mass and obesity-associated protein influence Alzheimer’s disease progression through neuroinflammation,circular RNAs dysregulation,and autophagy-related mechanisms.In Parkinson’s disease,altered N^(6)-methyladenosine regulator expression affects dopaminergic neuron survival and stress responses by modulating mRNA stability and autophagy-related lncRNAs.In multiple sclerosis and amyotrophic lateral sclerosis,N^(6)-methyladenosine affects immune activation,myelin repair,and the regulation of disease-associated genes such as TDP-43.Beyond N^(6)-methyladenosine,other RNA methylation modifications-such as m1A,m5C,m7G,uracil,and pseudouridine-are implicated in neurodegenerative diseases through their regulation of mitochondrial function,RNA metabolism,and neuronal stress responses.Additionally,N^(6)-methyladenosine exhibits cell type-specific functions:in microglia,it regulates inflammatory activation and phagocytic function;in astrocytes,it modulates metabolic homeostasis and glutamate-associated neurotoxicity;in neurons,it affects synaptic function and neurodegeneration-related gene expression;and in adult neural stem cells,it controls differentiation,neurogenesis,and cognitive plasticity.Recently,several small-molecule inhibitors targeting methyltransferase-like 3 or fat mass and obesity-associated protein have been developed to modulate N^(6)-methyladenosine modification,providing new opportunities for disease intervention,with the targeting of N⁶-methyladenosine-related pathways emerging as a promising therapeutic strategy.However,challenges persist in optimizing the specificity and delivery of these therapeutic approaches.
文摘The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications.
基金financially supported by the Natural Science Foundation of Wuhan City (Chenguang Project) (No.2024040801020331)the Natural Science Foundation of Hubei Province of China (No.2023AFB402)+1 种基金the National Key Research and Development Program of China (No.2023YFE0210200)Interdisciplinary Research Program of HUST。
文摘DNA methylation is an important promising biomarker for cancer diagnosis and monitoring.Therefore,the assessment of DNA methylation levels is helpful for the prognosis and diagnosis of cancer.However,it is still a huge challenge to sensitively and accurately quantify the levels of DNA methylation in clinical sample.In this work,we proposed a protospacer adjacent motif(PAM)-free mediated CRISPR-Cas12a ultra-sensitive and quantitative DNA methylation detection method.Through recognizing the ds DNA with toehold region,CRISPR-Cas12a not only got rid of the limitation of PAM,but also improved its distinction ability for single Cp G site methylation,nearly 5-fold that of conventional PAM-containing ds DNA.We further introduced assist-strand and design an artificial mismatch to greatly improve the ability to distinguish single Cp G methylation site.Our results showed that the discrimination factor was >200.Then,we constructed toe-ds DNA by using “heating and freezing”,which made our method universally applicable and feasible.In addition,we greatly simplified the difficulty of primer design.Our method detected four highly methylated genes acyl carrier protein(ACP),CLV3/ESR-related(CLE),Disabled(DAB) and Homeobox(HOX) with a detection limit of 0.01 % and excellent linearity in DNA methylation standards.Then,we verified the clinical utility of this method in 29 hepatocellular carcinomas,11 ovarian cancers and4 health people.In conclusion,we have successfully constructed a PAM-free CRISPR-Cas12a DNA methylation quantification method,which achieves high congruence in sensitivity,specificity and universality,fully demonstrating its significant clinical application value.
基金supported by 111 Project(Grant No.B17043)China Postdoctoral Science Foundation(Grant No.2022M723425).
文摘Fig(Ficus carica L.)with purple-red peel cultivars are popular among consumers and exhibit better storability.While DNA methylation influences fruit ripening and color development,its specific role in fig fruit remains unclear.This study explores the impact of DNA methylation on the fig peel coloration.Enzymatic colorimetric detection revealed that the level of‘Purple Peel’fig DNA methylation decreases with fig fruit ripening and coloring.Treatment of young fruit with the DNA-methylation inhibitor azacytidine induced peel coloration,suggesting that a decrease in DNA-methylation level promotes fig peel coloration.Seven members of DNA methyltransferases and three members of DNA demethylases were identified from a high-level fig genome,highlighting FcMET1 and FcDRM2 as stable proteins,ensuring functional expression.Reference to the Arabidopsis protein interaction network map predicted that FcMET1 is in a central position,suggesting a crucial regulatory role in multiple biological processes.Correlation analysis revealed a positive correlation between FcMET1 expression during peel development and the level of total DNA methylation.Weighted gene co-expression network analysis identified co-expression of FcMET1 with the color-related transcription factors MYB,bHLH and WD40,as well as with eight structural genes in the flavonoid-biosynthesis pathway.The expression of FcUFGT3 was negatively correlated with that of FcMET1.McrBC-PCR and Bisulfite Sequencing detection showed that a low methylation level of the FcUFGT3 promoter corresponds with its high expression in colored fig.This investigation of the mechanism of DNA methylation provides a theoretical basis for understanding the role of DNA-methylation modifications in fig ripening and coloring.
基金the support from National Natural Science Foundation of China(No.22161132006)Key R&D Program of Zhejiang(No.2024SSYS0036)Westlake University Startup。
文摘Reader proteins that bind specific methyllysine are important to biological functions of lysine methylation,but readers of many methyllysine sites are still unknown.Therefore,development of covalent probes is important to identify readers from cell samples so as to understand biological roles of lysine methylation.Generally,readers bind methyllysine via aromatic cages that contain tryptophan,tyrosine and phenylalanine,that offer a unique motif for selective crosslinking.We recently reported a site-selective tryptophan crosslinking strategy based on dimethylsulfonium that mimics dimethyllysine to crosslink tryptophan in aromatic cages of readers.Since tyrosine is a key residue for binding affinity to methyllysine,especially some readers that do not contain tryptophan residues in the binding pocket.Here we developed strategies of site-selective crosslinking to tyrosine.Ultraviolet(UV)source was applied to excite tyrosine at neutral pH or phenoxide at basic p H,and subsequent single-electron transfer(SET)from Tyr*to sulfonium inside the binding pocket enables selective crosslinking.In consequence,methyllysine readers with tyrosine-containing aromatic cages could be selectively crosslinked by site-specific sulfonium peptide probes.In addition,we expanded substrates from aromatic cages to tyrosine residues of proximate contact with sulfonium probes.The pair of LgBiT and SmBiT exhibited orthogonal crosslinking in complicated cell samples.As a result,we may expand sulfonium tools to target local tyrosine in future investigations.
文摘Detecting lung cancer early is crucial for improving survival rates,yet it remains a significant challenge due to many cases being diagnosed at advanced stages.This review aims to provide advances in epigenetics which have highlighted DNA methylation patterns as promising biomarkers for early detection,prognosis,and treatment response in lung cancer.Techniques like bisulfite conversion followed by PCR,digital droplet polymerase chain reaction,and next-generation sequencing are commonly used for detecting these methylation patterns,which occur early in the cancer development process and can be detected in non-invasive samples like blood and sputum.Key genes such as SHOX2 and RASSF1A have demonstrated high sensitivity and specificity in clinical studies,making them crucial for diagnostic purposes.However,several challenges remain to be overcome before these biomarkers can be widely adopted for use in clinical practice.Standardizing the assays and validating their effectiveness are critical steps.Additionally,integrating methylation biomarkers with existing diagnostic tools could significantly enhance the accuracy of lung cancer detection,providing a more comprehensive diagnostic approach.Although progress has been made in understanding and utilizing DNA methylation patterns for lung cancer detection,more research and extensive clinical trials are necessary to fully harness their potential.These efforts will help establish the robustness of methylation patterns as biomarkers and therapeutic targets,ultimately leading to better prevention,diagnosis,and treatment strategies for lung cancer.In conclusion,DNA methylation states represent a promising avenue for advancing early detection,accurate diagnosis,and management of lung cancer.
文摘The methylation of DNA is a prevalent epigenetic modification that plays a crucial role in the pathological progression of ocular diseases.DNA methylation can regulate gene expression,thereby affecting cell function and signal transduction.Ophthalmic diseases are a kind of complex diseases,and their pathogenesis involves many factors such as genetic,environmental and individual differences.In addition,inflammation,oxidative stress and lipid metabolism,which abnormal DNA methylation is closely related to,are also considered to be major factors in eye diseases.The current understanding of DNA methylation in eye diseases is becoming more complex and comprehensive.In addition to the simple suppression of gene expression by hypermethylation,factors such as hypomethylation or demethylation,DNA methylation in non-promoter regions,interactions with other epigenetic modifications,and dynamic changes in DNA methylation must also be considered.Interestingly,although some genes are at abnormal methylation levels,their expression is not significantly changed,which indirectly reflects the complexity of gene regulation.This review aims to summarize and compare some relevant studies,and provide with new ideas and methods for the prevention and treatment of different eye diseases,such as glaucoma,retinoblastoma,and diabetic retinopathy.
基金supported by the Fundamental Research Funds for the Central Universities(2572020DR10)Project on the Investigation,Supervision and Industry Regulation of Rare and Endangered Species(2024)。
文摘Illegal hunting and trafficking of wildlife and their derivatives extort unprecedented population decline of relatively many species pushing them towards extinction.Notwithstanding contemporary counteracting interventions at international,regional,national and local levels,wildlife farming is advocated as an alternative approach to minimize pressure on wild populations.For wildlife farming to be an effective conservation tool,the integration of wildlife forensics is inevitable to allow distinction between captive-bred and wild-caught species.To this end,we analyzed methylation rates of skeletal muscle samples(pectoralis major,triceps brachii,gastrocnemius,biceps femoris,and neck muscles)from 60 captive-bred and 30 wild-caught Common Pheasant.A total of 13,507 differentially methylated regions were identified between five wild-caught and five captive-bred individuals through whole-genome methylation sequencing(WGBS).Based on the selected five methylation sites,LOC116231076,LOC116242223,ATAD2B,EGFL6,and HS2ST,quantitative detection technique was developed using methylation-sensitive high-resolution melting curve(MS-HRM)to measure methylation rates.The results showed significant differences in methylation rates at all differential sites between wild-caught and captive-bred individuals(|t|=0.67–33.10,P=0.000–0.042).The discrimination accuracy rate of each locus was highest in the gastrocnemius muscle and lowest in the neck muscle.The discrimination accuracy rate on LOC116231076,LOC116242223,ATAD2B,EGFL6,and HS2ST methylation sites for gastrocnemius muscle was 64.98%,100.00%,68.54%,63.79%,and 63.70%,respectively;and for neck muscle it was 67.42%,68.06%,83.61%,65.04%,and68.85%,respectively.The united discrimination accuracy rate of the five loci were 100.00%for gastrocnemius muscle,99.78%for biceps femoris muscle,97.52%for pectoralis major muscle,93.96%for triceps brachii muscle,and 91.63%for neck muscle,respectively.The panel also revealed excellent repeatability,reproducibility,sensitivity and universality to mammals and avian species.This study establishes an effective,accurate and low-cost identification technology for the identification of wild and farmed Common Pheasant,and also provides a reference for the development of identification methods for other species.
基金the Research Program of the Science and Technology Department of Yunnan Province,No.202101AY070001-204.
文摘BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this disease.AIM To explore the mechanism of miR-125a-5p in the pathogenesis of GC.METHODS The expression levels of miR-125a-5p,SERPINE1 and DNMT1 in GC cells and tissues were detected by real-time polymerase chain reaction(PCR)and Western blotting.Methylation-specific PCR was used to detect the level of miR-125a-5p methylation.A cell counting kit 8 assay,scratch test,and a Transwell assay were performed to detect the proliferation,migration,and invasiveness of HGC27 cells,respectively.The expression of the epithelial mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin and vimentin in HGC27 cells was detected by Western blotting,while the expression of vimentin was detected by immunofluorescence.RESULTS This study revealed that miR-125a-5p was expressed at low levels in GC clinical samples and cells and that miR-125a-5p overexpression inhibited the proliferation,migration,invasiveness and EMT of GC cells.Mechanistically,miR-125a-5p can reduce GC cell proliferation,promote E-cadherin expression,inhibit N-cadherin and vimentin expression,and reduce the EMT of GC cells,thus constraining GC cells to a certain extent.Moreover,DNMT1 inhibited miR-125a-5p expression by increasing the methylation of the miR-125a-5p promoter,thereby promoting the expression of SERPINE1,which acts together with miR-125a-5p to exert antagonistic effects on GC.CONCLUSION Our study revealed that DNMT1 promoted SERPINE1 protein expression by inducing miR-125a-5p methylation,which led to the proliferation,migration and occurrence of EMT in GC cells.
文摘BACKGROUND Epigenetic regulation of leptin(LEP)plays a critical role in metabolic disorders,yet its promoter methylation patterns in lean diabetic populations remain poorly characterized.Emerging evidence suggests DNA methylation may precede clinical hyperglycemia,offering potential for early risk stratification.While obesity-associated LEP methylation is well-studied,lean Asian populations who exhibit high diabetes prevalence despite lower adiposity,represent an underexplored cohort.This study hypothesizes that LEP promoter methylation in peripheral leukocytes decreases progressively from normoglycemia to prediabetes and type 2 diabetes mellitus(T2DM),correlating inversely with serum LEP levels in lean Chinese adults[body mass index(BMI)<24 kg/m^(2)].AIM To investigate LEP promoter methylation status and its association with serum LEP levels across glycemic states in lean Chinese adults.METHODS We enrolled 392 participants including 120 normoglycemic controls,94 prediabetes[44 impaired fasting glucose(IFG)/50 impaired glucose tolerance(IGT)],178 T2DM aged 40-60 years with BMI<24 kg/m^(2).Genomic DNA from peripheral leukocytes underwent bisulfite conversion followed by methylation-specific PCR to assess CpG methylation in the LEP promoter.Serum LEP was quantified via enzyme-linked immunosorbent assay,with other parameters measured through standard assays.Statistical analyses included analysis of variance,χ²tests,and Pearson correlation(Bonferroni-corrected P value).RESULTS Methylation frequencies declined progressively:59.2%(controls)reduced to 43.6%(prediabetes;IFG:38.6%,IGT:48%)reduced to 31.5%(T2DM)(all P<0.05 vs controls;T2DM vs IGT:P=0.030).Serum LEP levels increased significantly in T2DM(16.94±4.19μg/L)vs controls(11.33±3.10μg/L;P=0.002),with intermediate values in prediabetes(IFG:13.79±3.32μg/L;IGT:12.62±4.81μg/L).A near-perfect inverse correlation between methylation and LEP levels was observed(r=-0.95,95%CI:-0.97 to-0.92,P<0.001),persisting after adjusting for age and BMI(β=-0.91,P<0.001).CONCLUSION LEP promoter hypomethylation parallels worsening glycemic status in lean Chinese adults,suggesting its potential as a blood-based epigenetic biomarker for diabetes progression,pending validation in longitudinal cohorts.
基金supported by the Shanghai 3-year Public Health Action Plan(grant number:GWVI-11.1-39).
文摘Cyclic volatile methyl siloxanes(cVMSs)are widely used in industrial and consumer products because of their thermal stability,low reactivity,and reduced surface tension[1].Their extensive use has resulted in environmental pollution globally.Recognized as very persistent and very bioaccumulative(vPvB),compounds such as octamethylcyclotetrasiloxane(D4),decamethylcyclopentasiloxane(D5),and dodecamethylcyclohexasiloxane(D6)are regulated in the European Union[2]and are monitored worldwide.
基金supported by the National Natural Science Foundation of China(32070607)the National Key Research and Development Program of China(2020YFA0804000)the CAS Project for Young Scientists in Basic Research(YSBR-012).
文摘In the mammalian genome,most CpGs are methylated.However,CpGs within the CpG islands(CGIs)are largely unmethylated,which are important for gene expression regulation.The mechanism underlying the low methylation levels at CGIs remains largely elusive.KDM2 proteins(KDM2A and KDM2B)are H3K36me2 demethylases known to bind specifically at CGIs.Here,we report that depletion of each or both KDM2 proteins,or mutation of all their JmjC domains that harbor the H3K36me2 demethylation activity,leads to an increase in DNA methylation at selective CGIs.The Kdm2a/2b double knockout shows a stronger increase in DNA methylation compared with the single mutant of Kdm2a or Kdm2b,indicating that KDM2A and KDM2B redundantly regulate DNA methylation at CGIs.In addition,the increase of CGI DNA methylation upon mutations of KDM2 proteins is associated with the chromatin environment.Our findings reveal that KDM2A and KDM2B function redundantly in regulating DNA methylation at a subset of CGIs in an H3K36me2 demethylation-dependent manner.
基金National Key Research and Development Program of China,No.2016YFA0100800(to LC)International(Regional)Cooperation and Communication Program of the National Natural Science Foundation of China,No.81820108013(to LC)+3 种基金State Key Program of the National Natural Science Foundation of China,No.81330030(to LC)National Natural Science Foundation of China,Nos.82071370(to ZW),81301042(to LC)Shanghai Pujiang Program,No.19PJ1409200(to ZW)Shanghai Sailing Program,No.21YF1442400(to CL)。
文摘DNA methylation is a critical epigenetic regulator in the occurrence and development of diseases and is closely related to various functional responses in relation to spinal cord injury.To investigate the role of DNA methylation in spinal cord injury,we constructed a library with reduced-representation bisulfite sequencing data obtained at various time points(day 0-42)after spinal cord injury in mice.Global DNA methylation levels,specifically non-CpG(CHG and CHH)methylation levels,decreased modestly following spinal cord injury.Stages post-spinal cord injury were classified as early(day 0-3),intermediate(day7-14),and late(day 28-42)based on similarity and hie rarchical cluste ring of global DNA methylation patterns.The non-CpG methylation level,which included CHG and CHH methylation levels,was markedly reduced despite accounting for a minor proportion of total methylation abundance.At multiple genomic sites,including the 5’untranslated regions,promoter,exon,intron,and 3’untranslated regions,the non-CpG methylation level was markedly decreased following spinal cord injury,whereas the CpG methylation level remained unchanged at these locations.Approximately one-half of the differentially methylated regions were located in intergenic areas;the other differentially methylated regions in both CpG and non-CpG regions were cluste red in intron regions,where the DNA methylation level was highest.The function of genes associated with differentially methylated regions in promoter regions was also investigated.From Gene Ontology analysis results,DNA methylation was implicated in a number of essential functional responses to spinal cord injury,including neuronal synaptic connection creation and axon regeneration.Notably,neither CpG methylation nor non-CpG methylation was implicated in the functional response of glial or inflammatory cells.In summary,our work elucidated the dynamic pattern of DNA methylation in the spinal co rd following injury and identified reduced nonCpG methylation as an epigenetic target after spinal cord injury in mice.
基金funded by National High-Level Hospital Clinical Research Funding (2022-PUMCH-A-203)CAMS Innovation Fund for Medical Sciences (2021-I2M-1-001)+4 种基金Health Research & Special Projects Grant of China (201002020 and 201502005)The Integrated Entrusted Project of Research Funding at Peking Union Medical College Hospital (ZC201903347)the National Natural Science Foundation of China (81970495)Capital Health Development Scientific Research Fund (2022-2-4014)Peking Union Medical College Hospital Research Funding for Postdoc (kyfyjj202315)
文摘Colitis-associated colorectal cancer(CAC),a serious complication of ulcerative colitis(UC),is associated with a poor prognosis.The vitamin D receptor(VDR)is recognized for its protective role in UC and CAC through the maintenance of intestinal barrier integrity and the regulation of inflammation.This study demonstrates a significant reduction in m^(6)A-related genes,particularly methyltransferase like 14(METTL14),in UC and CAC patients and identifies an association between METTL14 and VDR.In the azoxymethane(AOM)/dextran sodium sulfate(DSS)-induced mousemodel,vitamin D treatment increases METTL14 expression and reduces tumorburden,while Vdr-knockout mice exhibit lower METTL14 levels and increased tumorigenesis.In vitro,the VDR agonist calcipotriol upregulates METTL14 in NCM460 cells,with this effect attenuated by VDR knockdown.VDRknockdown inDLD-1colon cancer cellsdecreases METTL14 expressionand promotes proliferation,which is reversed by METTL14 overexpression.Mechanistic studies reveal that VDR regulates METTL14 expression via promoter binding,modulating key target genes such as SOX4,DROSH,and PHLPP2.This study highlights the role of the VDR-METTL14 axis as a protective mechanism in CAC and suggests its potential as a therapeutic target for preventing and treating CAC.
文摘Homoisoflavonoids are in the subclass of the larger family of flavonoids having one more alkyl carbon than flavonoids. Among them, 8-C-Methylated homoisoflavones have not been extensively studied for synthesis and biological evaluation. Author’s current objective is to synthesize 8-C-Methylated homoisoflavones by the reaction of 3-C-methylated dihydrochalcones with N,N’-dimethyl (chloromethylene) ammonium chloride generated in situ from DMF and PCl<sub>5</sub> for one carbon extension at about room temperature. The 3-C-methylated dihydrochalcones were synthesized by the reduction of 3-C-methylated chalcones, which were prepared from 3-C-methylated acetophenones and aromatic aldehydes in the presence of base. All the synthesized novel homoisoflavones’s structures were characterized by NMR and Tandem Mass Spectrometry.
基金supported by the National Natural Science Foundation of China,Nos.82271283(to XC),91854115(to JW),31970044(to JW)the Natural Science Foundation of Beijing,No.7202001(to XC)the Scientific Research Project of Beijing Educational Committee,No.KM202010005022(to XC)。
文摘Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environmental toxin that causes Parkinson's disease.However,the mechanism by which Sal mediates dopaminergic neuronal death remains unclear.In this study,we found that Sal significantly enhanced the global level of N~6-methyladenosine(m~6A)RNA methylation in PC12 cells,mainly by inducing the downregulation of the expression of m~6A demethylases fat mass and obesity-associated protein(FTO)and alk B homolog 5(ALKBH5).RNA sequencing analysis showed that Sal downregulated the Hippo signaling pathway.The m~6A reader YTH domain-containing family protein 2(YTHDF2)promoted the degradation of m~6A-containing Yes-associated protein 1(YAP1)mRNA,which is a downstream key effector in the Hippo signaling pathway.Additionally,downregulation of YAP1 promoted autophagy,indicating that the mutual regulation between YAP1 and autophagy can lead to neurotoxicity.These findings reveal the role of Sal on m~6A RNA methylation and suggest that Sal may act as an RNA methylation inducer mediating dopaminergic neuronal death through YAP1 and autophagy.Our results provide greater insights into the neurotoxic effects of catechol isoquinolines compared with other studies and may be a reference for assessing the involvement of RNA methylation in the pathogenesis of Parkinson's disease.
基金supported by the grant from the National Natural Science Foundation of China (No. 21210003)
文摘RNA methylation modifications have been found for decades of years, which occur at different RNA types of numerous species, and their distribution is species-specific. However, people rarely know their biological functions. There are several identified methylation modifications in eukaryotic messenger RNA （mRNA）, such as NT-methylguanosine （mVG） at the cap, Nr-methyl-2＇-O-methyladenosine （m6Am）, 2＇-O-methylation （Nm） within the cap and the internal positions, and internal N6-methyladenosine （m6A） and 5-methylcytosine （mSC）. Among them, mTG cap was studied more clearly and found to have vital roles in several important mRNA processes like mRNA translation, stability and nuclear export, m6A as the most abundant modification in mRNA was found in the 1970s and has been proposed to function in mRNA splicing, translation, stability, transport and so on. mrA has been discovered as the first RNA reversible modification which is demethylated directly by human fat mass and obesity associated protein （FRO） and its homolog protein, alkylation repair ho- molog 5 （ALKBH5）. b-TO has a special demethylation mechanism that demethylases m6A to A through two over-oxidative intermediate states： N6-hydroxymethyladenosine （hm6A） and Nr-formyladenosine （frA）. The two newly discovered m6A demethylases, bTO and ALKBH5, significantly control energy homeostasis and spermatogenesis, respectively, indicating that the dynamic and reversible mrA, analogous to DNA and histone modifications, plays broad roles in biological kingdoms and brings us an emerging field ＂RNA Epige- netics＂. 5-methylcytosine （5mC） as an epigenetic mark in DNA has been studied widely, but mSC in mRNA is seldom explored. The bisulfide sequencing showed mSC is another abundant modification in mRNA, suggesting that it might be another RNA epigenetic mark. This review focuses on the main methylation modifications in mRNA to describe their formation, distribution, function and demethylation from the current knowledge and to provide future 19erspectives on functional studies.
文摘Pancreatic cancer(PanCa)presents a catastrophic disease with poor overall survival at advanced stages,with immediate requirement of new and effective treatment options.Besides genetic mutations,epigenetic dysregulation of signaling pathway-associated enriched genes are considered as novel therapeutic target.Mechanisms beneath the deoxyribonucleic acid methylation and its utility in developing of epi-drugs in PanCa are under trails.Combinations of epigenetic medicines with conventional cytotoxic treatments or targeted therapy are promising options to improving the dismal response and survival rate of PanCa patients.Recent studies have identified potentially valid pathways that support the prediction that future PanCa clinical trials will include vigorous testing of epigenomic therapies.Epigenetics thus promises to generate a significant amount of new knowledge of biological and medical importance.Our review could identify various components of epigenetic mechanisms known to be involved in the initiation and development of pancreatic ductal adenocarcinoma and related precancerous lesions,and novel pharmacological strategies that target these components could potentially lead to breakthroughs.We aim to highlight the possibilities that exist and the potential therapeutic interventions.
基金Supported by the Medical Talents of Wuhan Health and Family Planning Commission,No.2017[51](to Yu J)the Medical Talents of Wuhan Hospital of Traditional Chinese and Western Medicine(to Yu J)+1 种基金the Hubei Natural Science Foundation,No.2023AFB1091Wuhan Medical Research Project,No.WX23A36(to Yu J).
文摘BACKGROUND Cholangiocarcinoma(CCA),also known as bile duct cancer,is a devastating malignancy primarily affecting the biliary tract.AIM To assess their performance in clinical diagnosis and monitoring of CCA,plasma methylation and circulating tumor cells were detected.METHODS Plasma samples were collected from Hubei Cancer Hospital(n=156).Plasma DNA was tested to detect SHOX2,HOXA9,SEPTIN9,and RASSF1A methylation using TaqMan PCR.Circulating tumor cells(CTCs)were detected in the peripheral blood of patients using the United States Food and Drug Administration-approved cell search system before and after clinical therapy.The CCA diagnostic value was estimated using the area under the curve.The independent prognosis risk factors for patients with CCA were estimated using Cox and logistic regression analyses.RESULTS The sensitivity and specificity of the four DNA plasma methylations exhibited 64.74%sensitivity and 93.88%specificity for detecting CCA.The receiver operating characteristic curve of the combined value for CCA diagnosis in plasma was 0.828±0.032.RASSF1A plasma methylation was related to the prognosis of patients with CCA.We determined the prognostic hazard ratio for CCA using CTC count,tumor stage,methylation,and carbohydrate antigen 19-9 levels as key factors.Our overall survival nomogram achieved a C-index of 0.705(0.605-0.805).CONCLUSION SHOX2,HOXA9,SEPTIN9,and RASSF1A plasma methylation demonstrated increased sensitivity for diagnosing CCA.RASSF1A plasma methylation and CTCs were valuable predictors to assess CCA prognosis and recurrence.
基金supported by the Natural Science Foundation of Guangdong Province(Grant Nos.2022A1515111141 and 2023A1515010786)。
文摘DNA methylation plays important roles in regulating gene expression during development.However,little is known about the influence of DNA methylation on secondary metabolism during leaf development in the tea plant(Camellia sinensis).In this study,we combined the methylome,transcriptome,and metabolome to investigate the dynamic changes in DNA methylation and its potential regulatory roles in secondary metabolite biosynthesis.In this study,the level of genomic DNA methylation increased as leaf development progressed from tender to old leaf.It additionally exhibited a similar distribution across the genomic background at the two distinct developmental stages studied.Notably,integrated analysis of transcriptomic and methylomic data showed that DNA hypermethylation primarily occurred in genes of the phenylpropanoid,flavonoid,and terpenoid biosynthesis pathways.The effect of methylation on transcription of these secondary metabolite biosynthesis genes was dependent on the location of methylation(i.e.,in the promoter,gene or intergenic regions)and the sequence context(i.e.,CpG,CHG,or CHH).Changes in the content of catechins and terpenoids were consistent with the changes in gene transcription and the methylation state of structural genes,such as serine carboxypeptidase-like acyltransferases 1A(SCPL1A),leucoanthocyanidin reductase(LAR),and nerolidol synthase(NES).Our study provides valuable information for dissecting the effects of DNA methylation on regulation of genes involved in secondary metabolism during tea leaf development.
