ABSTRACT
Exercise is a major beneficial contributor to muscle metabolism, and health benefits acquired by exercise are a result of molecular shifts occurring across multiple molecular layers (i.e., epigenome, transcriptome, and proteome). Identifying robust, across-molecular level targets associated with exercise response, at both group and individual levels, is paramount to develop health guidelines and targeted health interventions. Sixteen, apparently healthy, moderately trained (VO2 max = 51.0 ± 10.6 mL min-1 kg-1 ) males (age range = 18-45 years) from the Gene SMART (Skeletal Muscle Adaptive Responses to Training) study completed a longitudinal study composed of 12-week high-intensity interval training (HIIT) intervention. Vastus lateralis muscle biopsies were collected at baseline and after 4, 8, and 12 weeks of HIIT. DNA methylation (~850 CpG sites) and proteomic (~3000 proteins) analyses were conducted at all time points. Mixed models were applied to estimate group and individual changes, and methylome and proteome integration was conducted using a holistic multilevel approach with the mixOmics package. A total of 461 proteins significantly changed over time (at 4, 8, and 12 weeks), whilst methylome overall shifted with training only one differentially methylated position (DMP) was significant (adj.p-value < .05). K-means analysis revealed cumulative protein changes by clusters of proteins that presented similar changes over time. Individual responses to training were observed in 101 proteins. Seven proteins had large effect-sizes >0.5, among them are two novel exercise-related proteins, LYRM7 and EPN1. Integration analysis showed bidirectional relationships between the methylome and proteome. We showed a significant influence of HIIT on the epigenome and more so on the proteome in human muscle, and uncovered groups of proteins clustering according to similar patterns across the exercise intervention. Individual responses to exercise were observed in the proteome with novel mitochondrial and metabolic proteins consistently changed across individuals. Future work is required to elucidate the role of these proteins in response to exercise.
Subject(s)
High-Intensity Interval Training , Proteome , Male , Humans , Infant , Epigenome , Longitudinal Studies , Proteomics , Muscle, Skeletal , Molecular Chaperones , Mitochondrial ProteinsABSTRACT
Salt is one of the most important environmental factors in crop growth and development. N6-methyladenosine (m6A) is an epigenetic modification that regulates plant-environment interaction at transcriptional and translational levels. Sugar beet is a salt-tolerant sugar-yielding crop, but how m6A modification affects its response to salt stress remains unknown. In this study, m6A-seq was used to explore the role of m6A modification in response to salt stress in sugar beet (Beta vulgaris). Transcriptome-wide m6A methylation profiles and physiological responses to high salinity were investigated in beet roots. After treatment with 300 mM NaCl, the activities of peroxidase and catalase, the root activity, and the contents of Na+, K+, and Ca2+ in the roots were significantly affected by salt stress. Compared with the control plants, 6904 differentially expressed genes (DEGs) and 566 differentially methylated peaks (DMPs) were identified. Association analysis revealed that 243 DEGs contained DMP, and 80% of these DEGs had expression patterns that were negatively correlated with the extent of m6A modification. Further analysis verified that m6A methylation may regulate the expression of some genes by controlling their mRNA stability. Functional analysis revealed that m6A modifications primarily affect the expression of genes involved in energy metabolism, transport, signal transduction, transcription factors, and cell wall organization. This study provides evidence that a post-transcriptional regulatory mechanism mediates gene expression during salt stress by affecting the stability of mRNA in the root.
Subject(s)
Beta vulgaris , Beta vulgaris/metabolism , Epigenome , Salt Stress/genetics , Transcriptome , Sugars/metabolism , Gene Expression Regulation, Plant , Plant Roots/metabolism , Stress, Physiological/geneticsABSTRACT
BACKGROUND: Dietary intake of antioxidants such as vitamins C and E protect against oxidative stress, and may also be associated with altered DNA methylation patterns. METHODS: We meta-analysed epigenome-wide association study (EWAS) results from 11,866 participants across eight population-based cohorts to evaluate the association between self-reported dietary and supplemental intake of vitamins C and E with DNA methylation. EWAS were adjusted for age, sex, BMI, caloric intake, blood cell type proportion, smoking status, alcohol consumption, and technical covariates. Significant results of the meta-analysis were subsequently evaluated in gene set enrichment analysis (GSEA) and expression quantitative trait methylation (eQTM) analysis. RESULTS: In meta-analysis, methylation at 4,656 CpG sites was significantly associated with vitamin C intake at FDR ≤ 0.05. The most significant CpG sites associated with vitamin C (at FDR ≤ 0.01) were enriched for pathways associated with systems development and cell signalling in GSEA, and were associated with downstream expression of genes enriched in the immune response in eQTM analysis. Furthermore, methylation at 160 CpG sites was significantly associated with vitamin E intake at FDR ≤ 0.05, but GSEA and eQTM analysis of the top most significant CpG sites associated with vitamin E did not identify significant enrichment of any biological pathways investigated. CONCLUSIONS: We identified significant associations of many CpG sites with vitamin C and E intake, and our results suggest that vitamin C intake may be associated with systems development and the immune response.
Subject(s)
Ascorbic Acid , DNA Methylation , Humans , Epigenome , Vitamins/pharmacology , Vitamin E , Genome-Wide Association Study/methods , CpG Islands , Epigenesis, GeneticABSTRACT
The epitranscriptomic mark N6-methyladenosine (m6A), which is the predominant internal modification in RNA, is important for plant responses to diverse stresses. Multiple environmental stresses caused by the tea-withering process can greatly influence the accumulation of specialized metabolites and the formation of tea flavor. However, the effects of the m6A-mediated regulatory mechanism on flavor-related metabolic pathways in tea leaves remain relatively uncharacterized. We performed an integrated RNA methylome and transcriptome analysis to explore the m6A-mediated regulatory mechanism and its effects on flavonoid and terpenoid metabolism in tea (Camellia sinensis) leaves under solar-withering conditions. Dynamic changes in global m6A level in tea leaves were mainly controlled by two m6A erasers (CsALKBH4A and CsALKBH4B) during solar-withering treatments. Differentially methylated peak-associated genes following solar-withering treatments with different shading rates were assigned to terpenoid biosynthesis and spliceosome pathways. Further analyses indicated that CsALKBH4-driven RNA demethylation can directly affect the accumulation of volatile terpenoids by mediating the stability and abundance of terpenoid biosynthesis-related transcripts and also indirectly influence the flavonoid, catechin, and theaflavin contents by triggering alternative splicing-mediated regulation. Our findings revealed a novel layer of epitranscriptomic gene regulation in tea flavor-related metabolic pathways and established a link between the m6A-mediated regulatory mechanism and the formation of tea flavor under solar-withering conditions.
Subject(s)
Camellia sinensis , RNA , RNA/metabolism , Epigenome , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Leaves/genetics , Plant Leaves/metabolism , Camellia sinensis/genetics , Camellia sinensis/metabolism , Flavonoids , Terpenes/metabolism , Tea/metabolism , Gene Expression Regulation, PlantABSTRACT
PURPOSE: Examining epigenetic patterns is a crucial step in identifying molecular changes of disease pathophysiology, with DNA methylation as the most accessible epigenetic measure. Diet is suggested to affect metabolism and health via epigenetic modifications. Thus, our aim was to explore the association between food consumption and DNA methylation. METHODS: Epigenome-wide association studies were conducted in three cohorts: KORA FF4, TwinsUK, and Leiden Longevity Study, and 37 dietary exposures were evaluated. Food group definition was harmonized across the three cohorts. DNA methylation was measured using Infinium MethylationEPIC BeadChip in KORA and Infinium HumanMethylation450 BeadChip in the Leiden study and the TwinsUK study. Overall, data from 2293 middle-aged men and women were included. A fixed-effects meta-analysis pooled study-specific estimates. The significance threshold was set at 0.05 for false-discovery rate-adjusted p values per food group. RESULTS: We identified significant associations between the methylation level of CpG sites and the consumption of onions and garlic (2), nuts and seeds (18), milk (1), cream (11), plant oils (4), butter (13), and alcoholic beverages (27). The signals targeted genes of metabolic health relevance, for example, GLI1, RPTOR, and DIO1, among others. CONCLUSION: This EWAS is unique with its focus on food groups that are part of a Western diet. Significant findings were mostly related to food groups with a high-fat content.
Subject(s)
Epigenome , Genome-Wide Association Study , Male , Middle Aged , Humans , Female , Epigenome/genetics , CpG Islands , Epigenesis, Genetic , DNA MethylationABSTRACT
Sorghum ("Jitian 3") is a salt-tolerant seed cultivar used regularly in marginal lands, such as those with saline soils. Herein, we examined the potential of employing gibberellic acid (GA3) as an inducer of sorghum development during salt stress. Thus far, there have been no reports on the signaling network involved in the GA3-mediated regulation of sorghum development. In this study, we demonstrated that the stimulating properties of 50 mg/L GA3 on sorghum development was far superior to other GA3 concentrations under a 150 mM NaCl salinity condition. Furthermore, using methylated RNA immunoprecipitation sequencing (MeRIP-seq), we established an m6A methylation (m6A-M) profile in sorghum following exposure to 50 mg/L GA3. Overall, 23,363 m6A peaks and 16,200 m6A genes were screened among the GA3-treated and control leaves. These identified peaks were shown to be primarily enriched in the coding, as were the 3'- and 5'-untranslated regions. In addition, we employed m6A and transcript expression cross-analysis to identify 70 genes with differential transcript expression and simultaneous m6A-M. Intriguingly, the principal gene, LOC8066282, which is associated with LOC8084853, was shown to be intricately linked to the phosphatidylinositol signaling, which in turn regulates sorghum development and response to salt stress. This investigation presents a novel RNA m6A-M profile in sorghum, which may facilitate new insights into the underlying signaling behind salt stress resistance. This work will also benefit future investigations on foreign GA3 administration of sorghum.
Subject(s)
Sorghum , Epigenome , Gene Expression Profiling , Phosphatidylinositols/metabolism , RNA/metabolism , Salt Stress/genetics , Sodium Chloride/metabolism , Sodium Chloride/pharmacology , Soil , Sorghum/metabolism , Transcriptome , Untranslated RegionsABSTRACT
DNA methylation is the most studied epigenetic mark in both plants and animals. The gold standard for assaying genome-wide DNA methylation at single-base resolution is whole-genome bisulfite sequencing (WGBS). Here, we describe an improved procedure for WGBS and original bioinformatic workflows applied to unravel tissue-specific variations of the methylome in relation to gene expression and accumulation of secondary metabolites in the medicinal plant Catharanthus roseus.
Subject(s)
Epigenome , High-Throughput Nucleotide Sequencing , Animals , DNA/genetics , DNA Methylation , Epigenomics/methods , High-Throughput Nucleotide Sequencing/methods , Organ Specificity/genetics , Sequence Analysis, DNA/methods , SulfitesABSTRACT
In this interview, Professor Peter W Laird speaks with Storm Johnson, Commissioning Editor for Epigenomics, on his work to date in the field of cancer epigenetics. Dr Peter W Laird is a Professor at Van Andel Institute (VAI) in Grand Rapids, Michigan. He earned his B.S. and M.S., Cum Laude, from the University of Leiden, The Netherlands. He trained for his PhD with Dr Piet Borst, The Netherlands Cancer Institute, and as a postdoc with Dr Anton Berns, The Netherlands Cancer Institute, and with Dr Rudolf Jaenisch, at the Whitehead Institute for Biomedical Research in Cambridge, MA, USA. He joined the faculty at the University of Southern California in 1996, where he served as the Founding Director of the USC Epigenome Center and also as the Leader of the Epigenetics and Regulation Program of the Norris Comprehensive Cancer Center. In 2014, he relocated to VAI to join Dr Peter Jones in building an internationally acclaimed research center focused on Epigenetics. Dr Laird published the first demonstration of the causal role for DNA methylation in oncogenesis (Cell, 1995) [1]. He served as the Principal Investigator for all DNA methylation data production for the Cancer Genome Atlas (TCGA) and led many TCGA analysis efforts. He has been awarded 10 patents related to DNA methylation technology by the United States Patent and Trademark Office, one of which is the basis for the first US FDA-approved blood-based DNA methylation assay for cancer (Epi proColon). His research findings include the report of a close link between DNA methylation and BRAF mutation in colorectal cancer (Nature Genetics, 2006) [2], the discovery that embryonic stem cell polycomb repressor targets are predisposed to abnormal DNA methylation in cancer (Nature Genetics, 2007) [3], the identification of a novel epigenetic subtype of glioma (G-CIMP), tightly associated with IDH1 mutation (Cancer Cell, 2010) [4], and the connection between nuclear architecture, late replication, and domains of epigenetic instability (Nature Genetics, 2011) [5], later showing a link with mitotic cell division, thus providing a mechanistic explanation for the loss of DNA methylation in aging and cancer first described four decades ago (Nature Genetics, 2018) [6].
Subject(s)
Epigenomics , Neoplasms , DNA Methylation , Epigenesis, Genetic , Epigenome , Humans , Male , Neoplasms/genetics , United StatesABSTRACT
Coffee and tea are extensively consumed beverages worldwide which have received considerable attention regarding health. Intake of these beverages is consistently linked to, among others, reduced risk of diabetes and liver diseases; however, the mechanisms of action remain elusive. Epigenetics is suggested as a mechanism mediating the effects of dietary and lifestyle factors on disease onset. Here we report the results from epigenome-wide association studies (EWAS) on coffee and tea consumption in 15,789 participants of European and African-American ancestries from 15 cohorts. EWAS meta-analysis of coffee consumption reveals 11 CpGs surpassing the epigenome-wide significance threshold (P-value <1.1×10-7), which annotated to the AHRR, F2RL3, FLJ43663, HDAC4, GFI1 and PHGDH genes. Among them, cg14476101 is significantly associated with expression of the PHGDH and risk of fatty liver disease. Knockdown of PHGDH expression in liver cells shows a correlation with expression levels of genes associated with circulating lipids, suggesting a role of PHGDH in hepatic-lipid metabolism. EWAS meta-analysis on tea consumption reveals no significant association, only two CpGs annotated to CACNA1A and PRDM16 genes show suggestive association (P-value <5.0×10-6). These findings indicate that coffee-associated changes in DNA methylation levels may explain the mechanism of action of coffee consumption in conferring risk of diseases.
Subject(s)
Coffee/adverse effects , DNA Methylation , Epigenome , Tea/adverse effects , Adult , Aged , Aged, 80 and over , Cohort Studies , CpG Islands , Epigenesis, Genetic , Female , Gene Knockdown Techniques , Genome-Wide Association Study , Humans , Liver/enzymology , Male , Middle Aged , Phosphoglycerate Dehydrogenase/antagonists & inhibitors , Phosphoglycerate Dehydrogenase/genetics , Risk FactorsABSTRACT
BACKGROUND: Bee venom is a promising agent for cancer treatment due to its selective cytotoxic potential for cancer cells through apoptotic pathways. However, there is no evidence for changes in the epigenome and mitochondrial DNA copy numbers after bee venom application. The purpose of this study was to determine the impact of bee venom on cytosine modifications and mitochondrial DNA copy number variation. METHODS: A broad range of methods was applied to elucidate the impact of bee venom on neoplastic cells. These included MTT assay for detection of cytotoxicity, immunostaining of cytosine modifications and mitochondria, assessment of cellular morphology by flow cytometry, and quantification of mitochondrial DNA copy numbers using QPCR. RESULTS: Bee venom-induced cell death was selective for cancer cells, where it triggered a response characterized by alteration of cytosine modification. In contrast, normal cells were more resistant to DNA modifications. Furthermore, application of the venom resulted in variation of mitochondrial membrane permeability and mitochondrial DNA copy numbers, together with alterations in cell morphology, manifesting as reduced affected cell size. CONCLUSION: The study findings suggest that bee venom can be used as a selective DNA (de)methylating agent in cancer. Various agents (such as decitabine and 5-azacytidine) have been synthesized and developed for cancer treatment, and a range of syntheses and preparation and application methods have been described for these patented drugs. However, to the best of our knowledge, no previous research has investigated the use of bee venom or any component thereof for epigenetic therapy in cancer cells.
Subject(s)
Bee Venoms/pharmacology , DNA, Mitochondrial/drug effects , Epigenome/drug effects , Mitochondria/drug effects , Animals , Apitherapy , Cell Line, Tumor , Cell Shape , Cell Size , DNA Copy Number Variations/drug effects , Epigenesis, Genetic/drug effects , Epigenome/genetics , Hep G2 Cells , Humans , Mice , Mitochondria/genetics , Mitochondrial Membranes/drug effects , Mitochondrial Membranes/metabolism , NIH 3T3 Cells , Permeability/drug effectsABSTRACT
The societal burden of non-communicable disease is closely linked with environmental exposures and lifestyle behaviours, including the adherence to a poor maternal diet from the earliest preimplantation period of the life course onwards. Epigenetic variations caused by a compromised maternal nutritional status can affect embryonic development. This review summarises the main epigenetic modifications in mammals, especially DNA methylation, histone modifications, and ncRNA. These epigenetic changes can compromise the health of the offspring later in life. We discuss different types of nutritional stressors in human and animal models, such as maternal undernutrition, seasonal diets, low-protein diet, high-fat diet, and synthetic folic acid supplement use, and how these nutritional exposures epigenetically affect target genes and their outcomes. In addition, we review the concept of thrifty genes during the preimplantation period, and some examples that relate to epigenetic change and diet. Finally, we discuss different examples of maternal diets, their effect on outcomes, and their relationship with assisted reproductive technology (ART), including their implications on epigenetic modifications.
Subject(s)
Diet, High-Fat/adverse effects , Embryonic Development/genetics , Epigenesis, Genetic/genetics , Epigenome/genetics , Reproductive Techniques, Assisted/adverse effects , Uterus/physiology , Animals , DNA Methylation/genetics , Female , HumansABSTRACT
DNA methylation is an epigenetic event that plays critical roles in the pathogenesis, progression, and treatment of human diseases. In this study, we investigated the epigenetic mechanisms for Astragalus polysaccharide (APS)-improved osteoporosis in a rat model. The results showed that APS significantly changed the DNA methylome in colonic epithelia with great efficiency. Gene set enrichment analysis (GSEA) based on differentially methylated sites (DMSs) revealed that APS caused promoter DNA methylation changes of genes associated with calcium homeostasis, osteoclast/osteoblast balance, Wnt signaling, and hormone-related processes. Further analysis showed high consistency of APS-induced gene methylomic changes in colonic epithelia and its effects on diabetes, virus infection, and wound healing, which had been reported already. Moreover, we suggested new functions and the involved mechanisms of APS in heart disease, neurological disorder, reproductive problem, and olfactory dysfunction. In this study, we offered epigenetic mechanisms for APS-improved osteoporosis. More importantly, we proposed and proved a reliable method to explore the beneficial effects of bioactive polysaccharides by studying DNA methylation changes at nonfocal sites. We firmly believed the promising prospects of this method for its great efficiency, rapidness, and economy in exploring possible beneficial or therapeutic effects of functional macromolecules with one single experiment.
Subject(s)
Astragalus Plant/chemistry , Drugs, Chinese Herbal/administration & dosage , Osteoporosis/drug therapy , Polysaccharides/administration & dosage , Animals , Calcium/metabolism , DNA Methylation/drug effects , Disease Models, Animal , Drugs, Chinese Herbal/chemistry , Epigenesis, Genetic/drug effects , Epigenome/drug effects , Female , Humans , Osteoporosis/genetics , Osteoporosis/metabolism , Pilot Projects , Polysaccharides/chemistry , Rats , Rats, Sprague-DawleyABSTRACT
Ulcerative colitis (UC) is a prevalent relapsing-remitting inflammatory bowel disease whose pathogenetic mechanisms remain elusive. In the present study, colonic biopsies samples from three UC patients treated in the Traditional Chinese Medicine Hospital and three healthy controls were obtained. The genome-wide mRNA and lncRNA expression of the samples were profiled through Agilent gene expression microarray. Moreover, the genome-wide DNA methylation dataset of normal and UC colon tissues was also downloaded from GEO for a collaborative analysis. Differential expression of lncRNA (DELs) and mRNAs (DEMs) in UC samples compared with healthy samples were identified by using limma Bioconductor package. Differentially methylated promoters (DMPs) in UC samples compared with controls were obtained through comparing the average methylation level of CpGs located at promoters by using t-test. Functional enrichment analysis was performed by the DAVID. STRING database was applied to the construction of gene functional interaction network. As a result, 2090 DEMs and 1242 DELs were screened out in UC samples that were closely associated with processes related to complement and coagulation cascades, osteoclast differentiation vaccinia, and hemorrhagic diseases. A total of 90 DEMs and 72 DELs were retained for the construction of functional network for the promoters of their corresponding genes were identified as DMPs. S100A9, HECW2, SOD3 and HIX0114733 showed high interaction degrees in the functional network, and expression of S100A9 was confirmed to be significantly elevated in colon tissues of UC patients compared with that of controls by qRT-PCR that was consistent with gene microarray analysis. These indicate that S100A9 could potentially be used as predictive biomarkers in UC.
Subject(s)
Calgranulin B/genetics , Colitis, Ulcerative/genetics , DNA Methylation , Epigenome , Transcriptome , Calgranulin B/metabolism , Case-Control Studies , Colitis, Ulcerative/diagnosis , Colitis, Ulcerative/metabolism , Colon/metabolism , Colon/pathology , Gene Expression Profiling , Gene Regulatory Networks , Genetic Association Studies , Genetic Markers , Genetic Predisposition to Disease , Humans , Oligonucleotide Array Sequence Analysis , Phenotype , Protein Interaction Maps , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
Puberty is programmed through a multifactorial gene network which works to activate the pulsatile secretion of the gonadotropin releasing hormone (GnRH), and subsequently elevate circulating levels of the pituitary gonadotropins that stimulate gonadal activity. Although this developmental transition normally occurs at a limited age-range in individuals of the same genetic background and environment, pubertal onset can occur prematurely or be delayed following changes in ambient conditions, or due to genetic variations or mutations, many of which have remained elusive due to their location in distal regulatory elements. Growing evidence is pointing to a pivotal role for the epigenome in regulating key genes in the reproductive hypothalamus and pituitary at this time, which might mediate some of the plasticity of pubertal timing. This review will address epigenetic mechanisms which have been demonstrated in the KNDy neurons that increase the output of pulsatile GnRH, and those involved in activation of the GnRH gene and its receptor, and describes how GnRH utilizes epigenetic mechanisms to stimulate transcription of the pituitary gonadotropin genes in the context of the chromatin landscape.
Subject(s)
Epigenome/physiology , Hypothalamus/metabolism , Pituitary Gland/metabolism , Sexual Maturation/genetics , Animals , Epigenesis, Genetic/physiology , Female , Humans , Male , Neurons/metabolism , Puberty/genetics , Reproduction/geneticsABSTRACT
Catharanthus roseus produces a wide spectrum of monoterpene indole alkaloids (MIAs). MIA biosynthesis requires a tightly coordinated pathway involving more than 30 enzymatic steps that are spatio-temporally and environmentally regulated so that some MIAs specifically accumulate in restricted plant parts. The first regulatory layer involves a complex network of transcription factors from the basic Helix Loop Helix (bHLH) or AP2 families. In the present manuscript, we investigated whether an additional epigenetic layer could control the organ-, developmental- and environmental-specificity of MIA accumulation. We used Whole-Genome Bisulfite Sequencing (WGBS) together with RNA-seq to identify differentially methylated and expressed genes among nine samples reflecting different plant organs and experimental conditions. Tissue specific gene expression was associated with specific methylation signatures depending on cytosine contexts and gene parts. Some genes encoding key enzymatic steps from the MIA pathway were found to be simultaneously differentially expressed and methylated in agreement with the corresponding MIA accumulation. In addition, we found that transcription factors were strikingly concerned by DNA methylation variations. Altogether, our integrative analysis supports an epigenetic regulation of specialized metabolisms in plants and more likely targeting transcription factors which in turn may control the expression of enzyme-encoding genes.
Subject(s)
Catharanthus/growth & development , Catharanthus/genetics , Catharanthus/metabolism , DNA Methylation , Indole Alkaloids/metabolism , Catharanthus/cytology , Enzymes/genetics , Enzymes/metabolism , Epigenome , Gene Expression Regulation, Plant , Monoterpenes/metabolism , Photosynthesis/genetics , Plant Cells/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Medicinal/cytology , Plants, Medicinal/genetics , Plants, Medicinal/growth & development , Plants, Medicinal/metabolism , Signal Transduction , Transcription Factors/genetics , Transcription Factors/metabolism , Whole Genome SequencingABSTRACT
Kashin-Beck disease (KBD) is an endemic chronic osteochondropathy. The etiology of KBD remains unknown. In this study, we conducted an integrative analysis of genome-wide DNA methylation and mRNA expression profiles between KBD and normal controls to identify novel candidate genes and pathways for KBD. Articular cartilage samples from 17 grade III KBD patients and 17 healthy controls were used in this study. DNA methylation profiling of knee cartilage and mRNA expression profile data were obtained from our previous studies. InCroMAP was performed to integrative analysis of genome-wide DNA methylation profiles and mRNA expression profiles. Gene ontology (GO) enrichment analysis was conducted by online DAVID 6.7. The quantitative real-time polymerase chain reaction (qPCR), Western blot, immunohistochemistry (IHC), and lentiviral vector transfection were used to validate one of the identified pathways. We identified 298 common genes (such as COL4A1, HOXA13, TNFAIP6 and TGFBI), 36 GO terms (including collagen function, skeletal system development, growth factor), and 32 KEGG pathways associated with KBD (including Selenocompound metabolism pathway, PI3K-Akt signaling pathway, and TGF-beta signaling pathway). Our results suggest the dysfunction of many genes and pathways implicated in the pathogenesis of KBD, most importantly, both the integrative analysis and in vitro study in KBD cartilage highlighted the importance of selenocompound metabolism pathway in the pathogenesis of KBD for the first time.
Subject(s)
DNA Methylation , Epigenome , Kashin-Beck Disease/genetics , RNA, Messenger/genetics , Selenium/metabolism , Transcriptome , Adult , Aged , Cartilage, Articular/metabolism , Cartilage, Articular/pathology , Case-Control Studies , Cells, Cultured , Epigenomics , Female , Gene Expression Profiling , Gene Regulatory Networks , Humans , Kashin-Beck Disease/diagnosis , Kashin-Beck Disease/metabolism , Male , Middle Aged , RNA, Messenger/metabolismABSTRACT
KEY MESSAGE: Pollen abortion could be mainly attributed to abnormal meiosis in the mutant. Multiomics analysis uncovered significant epigenetic variations between the mutant and its wild type during the pollen abortion process. Male sterility caused by aborted pollen can result in seedless fruit. A seedless Ponkan mandarin mutant (bud sport) was used to compare the transcriptome, methylome, and metabolome with its progenitor to understand the mechanism of citrus pollen abortion. Cytological observations showed that the anther of the mutant could form microspore mother cells, although the microspores failed to develop fertile pollen at the anther dehiscence stage. Based on pollen phenotypic analysis, pollen abortion could be mainly attributed to abnormal meiosis in the mutant. A transcriptome analysis uncovered the molecular mechanisms underlying pollen abortion between the mutant and its wild type. A total of 5421 differentially expressed genes were identified, and some of these genes were involved in the meiosis, hormone biosynthesis and signaling, carbohydrate, and flavonoid pathways. A total of 50,845 differentially methylated regions corresponding to 15,426 differentially methylated genes in the genic region were found between the mutant and its wild type by the methylome analysis. The expression level of these genes was negatively correlated with their methylation level, especially in the promoter regions. In addition, 197 differential metabolites were identified between the mutant and its wild type based on the metabolome analysis. The transcription and metabolome analysis further indicated that the expression of genes in the flavonoid, carbohydrate, and hormone metabolic pathways was significantly modulated in the pollen of the mutant. These results indicated that demethylation may alleviate the silencing of carbohydrate genes in the mutant, resulting in excessive starch and sugar hydrolysis and thereby causing pollen abortion in the mutant.
Subject(s)
Citrus/metabolism , Epigenome , Metabolome , Plant Proteins/metabolism , Pollen/metabolism , Transcriptome , Citrus/cytology , Citrus/genetics , Citrus/growth & development , DNA Methylation , Gene Expression Profiling , Gene Expression Regulation, Plant , Genes, Plant , Genotype , Meiosis , Plant Growth Regulators/metabolism , Plant Infertility/genetics , Plant Infertility/physiology , Plant Proteins/genetics , Pollen/genetics , Sequence AnalysisABSTRACT
BACKGROUND: DNA methylation (DNAm) age constitutes a powerful tool to assess the molecular age and overall health status of biological samples. Recently, it has been shown that tissue-specific DNAm age predictors may present superior performance compared to the pan- or multi-tissue counterparts. The skin is the largest organ in the body and bears important roles, such as body temperature control, barrier function, and protection from external insults. As a consequence of the constant and intimate interaction between the skin and the environment, current DNAm estimators, routinely trained using internal tissues which are influenced by other stimuli, are mostly inadequate to accurately predict skin DNAm age. RESULTS: In the present study, we developed a highly accurate skin-specific DNAm age predictor, using DNAm data obtained from 508 human skin samples. Based on the analysis of 2,266 CpG sites, we accurately calculated the DNAm age of cultured skin cells and human skin biopsies. Age estimation was sensitive to the biological age of the donor, cell passage, skin disease status, as well as treatment with senotherapeutic drugs. CONCLUSIONS: This highly accurate skin-specific DNAm age predictor constitutes a holistic tool that will be of great use in the analysis of human skin health status/molecular aging, as well as in the analysis of the potential of established and novel compounds to alter DNAm age.
Subject(s)
DNA Methylation/genetics , Epigenome/genetics , Healthy Aging/genetics , Skin/metabolism , Adult , Aged , Aged, 80 and over , Aging/genetics , Algorithms , CpG Islands/genetics , Epigenomics/methods , Female , Fibroblasts/metabolism , Fibroblasts/pathology , Health Status , Humans , Machine Learning , Male , Middle Aged , Skin/pathologyABSTRACT
A majority of the cases of primary male infertility are idiopathic with the underlying molecular mechanisms contributing to the pathophysiology as yet unknown. Effects of the environment can alter the sperm epigenome thereby impacting male reproductive health. Epigenetic mechanisms are crucial to understanding health and disease, and methylome alterations are now known to have far-reaching clinical implications. Here, we report the results from our pilot study, a first of its kind analysis of the effect of the traditional practice of yoga on human sperm quality. We find marked improvement in sperm characteristics in patients of idiopathic male infertility following a supervised 21-day yoga regimen. Furthermore, next-generation sequencing-based methylome analysis reveals alterations in the sperm epigenome of these patients. We find that the practice of yoga is associated with DNA methylation changes at nearly 400 genes, 147 of which were hypermethylated while 229 were hypomethylated. These included promoters of several genes linked to maintenance of fertility and genomic integrity. This novel piece of work draws a direct link between positive lifestyle practices and male reproductive health.