Epigenetic Regulation of Verticillium dahliae Virulence: Does DNA Methylation Level Play A Role?

Verticillium dahliae is the etiological agent of Verticillium wilt of olive. The virulence of Defoliating V. dahliae isolates usually displays differences and high plasticity. This work studied whether an epigenetic mechanism was involved in this plasticity. An inverse correlation between virulence and DNA methylation of protein-coding genes was found. A set of 831 genes was selected for their highly consistent inverse methylation profile and virulence in the five studied isolates. Of these genes, ATP-synthesis was highly represented, which indicates that the more virulent D isolates are, the more energy requirements they may have. Furthermore, there were numerous genes in the protein biosynthesis process: genes coding for the chromatin structure, which suggests that epigenetic changes may also affect chromatin condensation; many transmembrane transporter genes, which is consistent with denser compounds, traffic through membranes in more virulent isolates; a fucose-specific lectin that may play a role in the attachment to plant cell walls during the host infection process; and pathogenic cutinases that facilitate plant invasion and sporulation genes for rapid spreading alongside plants. Our findings support the notion that differences in the virulence of the Defoliating V. dahliae isolates may be controlled, at least to some extent, by an epigenetic mechanism.

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A fungal milRNA mediates epigenetic repression of a virulence gene in Verticillium dahliae

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2018.0309 ◽

2019 ◽

Vol 374 (1767) ◽

pp. 20180309 ◽

Cited By ~ 7

Author(s):

Yun Jin ◽

Jian-Hua Zhao ◽

Pan Zhao ◽

Tao Zhang ◽

Sheng Wang ◽

...

Keyword(s):

Rna Polymerase Ii ◽

Verticillium Dahliae ◽

Transcriptional Repression ◽

Expression Patterns ◽

Virulence Gene ◽

Hypothetical Protein ◽

Epigenetic Mechanism ◽

Fungal Virulence ◽

Protein Coding ◽

Noncanonical Pathway

MiRNAs in animals and plants play crucial roles in diverse developmental processes under both normal and stress conditions. miRNA-like small RNAs (milRNAs) identified in some fungi remain functionally uncharacterized. Here, we identified a number of milRNAs in Verticillium dahliae , a soil-borne fungal pathogen responsible for devastating wilt diseases in many crops. Accumulation of a V. dahliae milRNA1, named VdmilR1, was detected by RNA gel blotting. We show that the precursor gene VdMILR1 is transcribed by RNA polymerase II and is able to produce the mature VdmilR1, in a process independent of V. dahliae DCL (Dicer-like) and AGO (Argonaute) proteins. We found that an RNaseIII domain-containing protein, VdR3, is essential for V. dahliae and participates in VdmilR1 biogenesis. VdmilR1 targets a hypothetical protein-coding gene, VdHy1 , at the 3′UTR for transcriptional repression through increased histone H3K9 methylation of VdHy1 . Pathogenicity analysis reveals that VdHy1 is essential for fungal virulence. Together with the time difference in the expression patterns of VdmilR1 and VdHy1 during fungal infection in cotton plants, our findings identify a novel milRNA, VdmilR1, in V. dahliae synthesized by a noncanonical pathway that plays a regulatory role in pathogenicity and uncover an epigenetic mechanism for VdmilR1 in regulating a virulence target gene. This article is part of the theme issue ‘Biotic signalling sheds light on smart pest management’.

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Salivary DNA Methylation as an Epigenetic Biomarker for Head and Neck Cancer. Part I: A Diagnostic Accuracy Meta-Analysis

Journal of Personalized Medicine ◽

10.3390/jpm11060568 ◽

2021 ◽

Vol 11 (6) ◽

pp. 568

Author(s):

Óscar Rapado-González ◽

Cristina Martínez-Reglero ◽

Ángel Salgado-Barreira ◽

Laura Muinelo-Romay ◽

Juan Muinelo-Lorenzo ◽

...

Keyword(s):

Dna Methylation ◽

Head And Neck Cancer ◽

Diagnostic Accuracy ◽

Head And Neck ◽

Likelihood Ratio ◽

Neck Cancer ◽

Meta Analysis ◽

Positive Likelihood Ratio ◽

Epigenetic Mechanism ◽

Cochrane Library

DNA hypermethylation is an important epigenetic mechanism for gene expression inactivation in head and neck cancer (HNC). Saliva has emerged as a novel liquid biopsy representing a potential source of biomarkers. We performed a comprehensive meta-analysis to evaluate the overall diagnostic accuracy of salivary DNA methylation for detecting HNC. PubMed EMBASE, Web of Science, LILACS, and the Cochrane Library were searched. Study quality was assessed by the Quality Assessment for Studies of Diagnostic Accuracy-2, and sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (dOR), and their corresponding 95% confidence intervals (CIs) were calculated using a bivariate random-effect meta-analysis model. Meta-regression and subgroup analyses were performed to assess heterogeneity. Eighty-four study units from 18 articles with 8368 subjects were included. The pooled sensitivity and specificity of salivary DNA methylation were 0.39 and 0.87, respectively, while PLR and NLR were 3.68 and 0.63, respectively. The overall area under the curve (AUC) was 0.81 and the dOR was 8.34. The combination of methylated genes showed higher diagnostic accuracy (AUC, 0.92 and dOR, 36.97) than individual gene analysis (AUC, 0.77 and dOR, 6.02). These findings provide evidence regarding the potential clinical application of salivary DNA methylation for HNC diagnosis.

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Epigenome-wide associations between observed maternal sensitivity and offspring DNA methylation: a population-based prospective study in children

Psychological Medicine ◽

10.1017/s0033291720004353 ◽

2020 ◽

pp. 1-11

Author(s):

Lorenza Dall’ Aglio ◽

Jolien Rijlaarsdam ◽

Rosa H. Mulder ◽

Alexander Neumann ◽

Janine F. Felix ◽

...

Keyword(s):

Dna Methylation ◽

Stress Responses ◽

Association Studies ◽

Maternal Sensitivity ◽

Population Based ◽

Epigenetic Mechanism ◽

Developmental Problems ◽

Maternal Caregiving ◽

Typical Variation

Abstract Background Experimental work in animals has shown that DNA methylation (DNAm), an epigenetic mechanism regulating gene expression, is influenced by typical variation in maternal care. While emerging research in humans supports a similar association, studies to date have been limited to candidate gene and cross-sectional approaches, with a focus on extreme deviations in the caregiving environment. Methods Here, we explored the prospective association between typical variation in maternal sensitivity and offspring epigenome-wide DNAm, in a population-based cohort of children (N = 235). Maternal sensitivity was observed when children were 3- and 4-years-old. DNAm, quantified with the Infinium 450 K array, was extracted at age 6 (whole blood). The influence of methylation quantitative trait loci (mQTLs), DNAm at birth (cord blood), and confounders (socioeconomic status, maternal psychopathology) was considered in follow-up analyses. Results Genome-wide significant associations between maternal sensitivity and offspring DNAm were observed at 13 regions (p < 1.06 × 10−07), but not at single sites. Follow-up analyses indicated that associations at these regions were in part related to genetic factors, confounders, and baseline DNAm levels at birth, as evidenced by the presence of mQTLs at five regions and estimate attenuations. Robust associations with maternal sensitivity were found at four regions, annotated to ZBTB22, TAPBP, ZBTB12, and DOCK4. Conclusions These findings provide novel leads into the relationship between typical variation in maternal caregiving and offspring DNAm in humans, highlighting robust regions of associations, previously implicated in psychological and developmental problems, immune functioning, and stress responses.

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Impact of DNA methylation on 3D genome structure

Nature Communications ◽

10.1038/s41467-021-23142-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Diana Buitrago ◽

Mireia Labrador ◽

Juan Pablo Arcon ◽

Rafael Lema ◽

Oscar Flores ◽

...

Keyword(s):

Dna Methylation ◽

Chromatin Structure ◽

Chromatin Condensation ◽

Genome Structure ◽

Dna Methyltransferases ◽

Model System ◽

Structure And Function ◽

3D Genome ◽

Cellular Machinery ◽

And Function

AbstractDetermining the effect of DNA methylation on chromatin structure and function in higher organisms is challenging due to the extreme complexity of epigenetic regulation. We studied a simpler model system, budding yeast, that lacks DNA methylation machinery making it a perfect model system to study the intrinsic role of DNA methylation in chromatin structure and function. We expressed the murine DNA methyltransferases in Saccharomyces cerevisiae and analyzed the correlation between DNA methylation, nucleosome positioning, gene expression and 3D genome organization. Despite lacking the machinery for positioning and reading methylation marks, induced DNA methylation follows a conserved pattern with low methylation levels at the 5’ end of the gene increasing gradually toward the 3’ end, with concentration of methylated DNA in linkers and nucleosome free regions, and with actively expressed genes showing low and high levels of methylation at transcription start and terminating sites respectively, mimicking the patterns seen in mammals. We also see that DNA methylation increases chromatin condensation in peri-centromeric regions, decreases overall DNA flexibility, and favors the heterochromatin state. Taken together, these results demonstrate that methylation intrinsically modulates chromatin structure and function even in the absence of cellular machinery evolved to recognize and process the methylation signal.

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The Heterochromatin Landscape in Migrating Cells and the Importance of H3K27me3 for Associated Transcriptome Alterations

Cells ◽

10.3390/cells7110205 ◽

2018 ◽

Vol 7 (11) ◽

pp. 205 ◽

Cited By ~ 8

Author(s):

Tamar Segal ◽

Mali Salmon-Divon ◽

Gabi Gerlitz

Keyword(s):

Transcriptome Analysis ◽

Transcriptional Repression ◽

Chromatin Condensation ◽

Opposite Pattern ◽

Protein Coding ◽

Epigenetic Markers ◽

Protein Coding Genes ◽

Global Increase ◽

General Signature ◽

Migrating Cells

H3K9me3, H3K27me3, and H4K20me1 are epigenetic markers associated with chromatin condensation and transcriptional repression. Previously, we found that migration of melanoma cells is associated with and dependent on global chromatin condensation that includes a global increase in these markers. Taken together with more recent reports by others suggests it is a general signature of migrating cells. Here, to learn about the function of these markers in migrating cells, we mapped them by ChIP-seq analysis. This analysis revealed that induction of migration leads to expansion of these markers along the genome and to an increased overlapping between them. Significantly, induction of migration led to a higher increase in H3K9me3 and H4K20me1 signals at repetitive elements than at protein-coding genes, while an opposite pattern was found for H3K27me3. Transcriptome analysis revealed 182 altered genes following induction of migration, of which 33% are dependent on H3K27me3 for these changes. H3K27me3 was also required to prevent changes in the expression of 501 other genes upon induction of migration. Taken together, our results suggest that heterochromatinization in migrating cells is global and not restricted to specific genomic loci and that H3K27me3 is a key component in executing a migration-specific transcriptional plan.

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Global DNA methylation was changed by a maternal high-lipid, high-energy diet during gestation and lactation in male adult mice liver

British Journal Of Nutrition ◽

10.1017/s0007114515000252 ◽

2015 ◽

Vol 113 (7) ◽

pp. 1032-1039 ◽

Cited By ~ 24

Author(s):

Huan-Ling Yu ◽

Shan Dong ◽

Li-Fang Gao ◽

Li Li ◽

Yuan-Di Xi ◽

...

Keyword(s):

Dna Methylation ◽

Maternal Diet ◽

High Energy ◽

Methylation Pattern ◽

Epigenetic Mechanism ◽

Chow Diet ◽

Mrna Levels ◽

Promoter Regions ◽

Male Adult ◽

High Lipid

An epigenetic mechanism has been suggested to explain the effects of the maternal diet on the development of disease in offspring. The present study aimed to observe the effects of a maternal high-lipid, high-energy (HLE) diet on the DNA methylation pattern of male offspring in mice. Female C57BL/6J mice were fed an HLE diet during gestation and lactation. The genomic DNA methylations at promoter sites of genes in the liver, mRNA and protein levels of selected genes related to lipid and glucose metabolism were measured by microarray, real-time PCR and Western blot. The results indicated that the percentage of methylated DNA in offspring from dams that were fed an HLE diet was significantly higher than that from dams that were fed a chow diet, and most of these genes were hypermethylated in promoter regions. The nuclear protein content and mRNA levels of hypermethylated genes, such as PPARγ and liver X receptor α (LXRα), were decreased significantly in offspring in the HLE group. The results suggested that the DNA methylation profile in adult offspring livers was changed by the maternal HLE diet during gestation and lactation.

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Methylome and transcriptome analyses of soybean response to bean pyralid larvae

BMC Genomics ◽

10.1186/s12864-021-08140-w ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Wei-Ying Zeng ◽

Yu-Rong Tan ◽

Sheng-Feng Long ◽

Zu-Dong Sun ◽

Zhen-Guang Lai ◽

...

Keyword(s):

Dna Methylation ◽

Protein Biosynthesis ◽

Cell Structure ◽

Methylation Profile ◽

Primary Metabolism ◽

Global Methylation ◽

Genome Wide ◽

Differentially Methylated Genes ◽

Dna Methylation Profile ◽

Soybean Resistance

Abstract Background Bean pyralid is one of the major leaf-feeding insects that affect soybean crops. DNA methylation can control the networks of gene expressions, and it plays an important role in responses to biotic stress. However, at present the genome-wide DNA methylation profile of the soybean resistance to bean pyralid has not been reported so far. Results Using whole-genome bisulfite sequencing (WGBS) and RNA-sequencing (RNA-seq), we analyzed the highly resistant material (Gantai-2-2, HRK) and highly susceptible material (Wan82–178, HSK), under bean pyralid larvae feeding 0 h and 48 h, to clarify the molecular mechanism of the soybean resistance and explore its insect-resistant genes. We identified 2194, 6872, 39,704 and 40,018 differentially methylated regions (DMRs), as well as 497, 1594, 9596 and 9554 differentially methylated genes (DMGs) in the HRK0/HRK48, HSK0/HSK48, HSK0/HRK0 and HSK48/HRK48 comparisons, respectively. Through the analysis of global methylation and transcription, 265 differentially expressed genes (DEGs) were negatively correlated with DMGs, there were 34, 49, 141 and 116 negatively correlated genes in the HRK0/HRK48, HSK0/HSK48, HSK0/HRK0 and HSK48/HRK48, respectively. The MapMan cluster analysis showed that 114 negatively correlated genes were clustered in 24 pathways, such as protein biosynthesis and modification; primary metabolism; secondary metabolism; cell cycle, cell structure and component; RNA biosynthesis and processing, and so on. Moreover, CRK40; CRK62; STK; MAPK9; L-type lectin-domain containing receptor kinase VIII.2; CesA; CSI1; fimbrin-1; KIN-14B; KIN-14 N; KIN-4A; cytochrome P450 81E8; BEE1; ERF; bHLH25; bHLH79; GATA26, were likely regulatory genes involved in the soybean responses to bean pyralid larvae. Finally, 5 DMRs were further validated that the genome-wide DNA data were reliable through PS-PCR and 5 DEGs were confirmed the relationship between DNA methylation and gene expression by qRT-PCR. The results showed an excellent agreement with deep sequencing. Conclusions Genome-wide DNA methylation profile of soybean response to bean pyralid was obtained for the first time. Several specific DMGs which participated in protein kinase, cell and organelle, flavonoid biosynthesis and transcription factor were further identified to be likely associated with soybean response to bean pyralid. Our data will provide better understanding of DNA methylation alteration and their potential role in soybean insect resistance.

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Deciphering DNA Methylation in HIV Infection

Frontiers in Immunology ◽

10.3389/fimmu.2021.795121 ◽

2021 ◽

Vol 12 ◽

Author(s):

Thilona Arumugam ◽

Upasana Ramphal ◽

Theolan Adimulam ◽

Romona Chinniah ◽

Veron Ramsuran

Keyword(s):

Dna Methylation ◽

Hiv Infection ◽

Therapeutic Strategy ◽

New Drugs ◽

Sub Saharan Africa ◽

Epigenetic Mechanism ◽

People Living With Hiv ◽

Modifying Factors ◽

Autoimmune Conditions ◽

Sub Saharan

With approximately 38 million people living with HIV/AIDS globally, and a further 1.5 million new global infections per year, it is imperative that we advance our understanding of all factors contributing to HIV infection. While most studies have focused on the influence of host genetic factors on HIV pathogenesis, epigenetic factors are gaining attention. Epigenetics involves alterations in gene expression without altering the DNA sequence. DNA methylation is a critical epigenetic mechanism that influences both viral and host factors. This review has five focal points, which examines (i) fluctuations in the expression of methylation modifying factors upon HIV infection (ii) the effect of DNA methylation on HIV viral genes and (iii) host genome (iv) inferences from other infectious and non-communicable diseases, we provide a list of HIV-associated host genes that are regulated by methylation in other disease models (v) the potential of DNA methylation as an epi-therapeutic strategy and biomarker. DNA methylation has also been shown to serve as a robust therapeutic strategy and precision medicine biomarker against diseases such as cancer and autoimmune conditions. Despite new drugs being discovered for HIV, drug resistance is a problem in high disease burden settings such as Sub-Saharan Africa. Furthermore, genetic therapies that are under investigation are irreversible and may have off target effects. Alternative therapies that are nongenetic are essential. In this review, we discuss the potential role of DNA methylation as a novel therapeutic intervention against HIV.

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Creating and validating a DNA methylation-based proxy for Interleukin-6

10.1101/2020.07.20.20156935 ◽

2020 ◽

Cited By ~ 2

Author(s):

Anna J Stevenson ◽

Danni A Gadd ◽

Robert Francis Hillary ◽

Daniel L. McCartney ◽

Archie Campbell ◽

...

Keyword(s):

Dna Methylation ◽

Cognitive Functioning ◽

Cognitive Ability ◽

Chronic Inflammation ◽

Interleukin 6 ◽

Epigenetic Mechanism ◽

Inverse Association ◽

Age Related ◽

Independent Test ◽

Methylation Score

Chronic inflammation is a pervasive feature of ageing and may be linked to age-related cognitive decline. However, population studies evaluating its relationship with cognitive functioning have produced heterogeneous results. A potential reason for this is the variability of inflammatory mediators which could lead to misclassifications of individuals' persisting levels of inflammation. The epigenetic mechanism DNA methylation has shown utility in indexing environmental exposures and could potentially be leveraged to provide proxy signatures of chronic inflammation. We conducted an elastic net regression of interleukin-6 (IL-6) in a cohort of 895 older adults (mean age: 69 years) to develop a DNA methylation-based predictor. The predictor was tested in an independent cohort (n=7,028 [417 with measured IL-6], mean age: 51 years).We examined the association between the DNA methylation IL-6 score and serum IL-6, its association with age and established correlates of circulating IL-6, and with cognitive ability. A weighted score from 12 DNA methylation sites optimally predicted IL-6 (independent test set R2=5.1%). In the independent test cohort, both measured IL-6, and the DNA methylation proxy, increased as a function of age (serum IL-6: n=417, β=0.02, SE=0.004 p=1.3x10-7; DNAm IL-6 score: n=7,028, β=0.02, SE=0.0009, p<2x10-16). Serum IL-6 was not found to associate with cognitive ability (n=417, β=-0.06, SE=0.05, p=0.19); however, an inverse association was identified between the DNA methylation score and cognitive functioning (n=7,028, β=-0.14, SE=0.02, pFDR=1.5x10-14). These results suggest DNA methylation-based predictors can be used as proxies for inflammatory markers, potentially allowing for reliable insights into the relationship between chronic inflammation and pertinent health outcomes.

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DNA methylation regulates transcriptional homeostasis of algal endosymbiosis in the coral modelAiptasia

10.1101/213066 ◽

2017 ◽

Cited By ~ 3

Author(s):

Yong Li ◽

Yi Jin Liew ◽

Guoxin Cui ◽

Maha J Cziesielski ◽

Noura Zahran ◽

...

Keyword(s):

Dna Methylation ◽

Molecular Mechanisms ◽

Model System ◽

Epigenetic Mechanism ◽

Symbiotic Relationship ◽

Epigenetic Mechanisms ◽

Genome Wide ◽

Spurious Transcription ◽

Coral Reef Ecosystems

The symbiotic relationship between cnidarians and dinoflagellates is the cornerstone of coral reef ecosystems. Although research is focusing on the molecular mechanisms underlying this symbiosis, the role of epigenetic mechanisms, which have been implicated in transcriptional regulation and acclimation to environmental change, is unknown. To assess the role of DNA methylation in the cnidarian-dinoflagellate symbiosis, we analyzed genome-wide CpG methylation, histone associations, and transcriptomic states of symbiotic and aposymbiotic anemones in the model systemAiptasia. We find methylated genes are marked by histone H3K36me3 and show significant reduction of spurious transcription and transcriptional noise, revealing a role of DNA methylation in the maintenance of transcriptional homeostasis. Changes in DNA methylation and expression show enrichment for symbiosis-related processes such as immunity, apoptosis, phagocytosis recognition and phagosome formation, and unveil intricate interactions between the underlying pathways. Our results demonstrate that DNA methylation provides an epigenetic mechanism of transcriptional homeostasis during symbiosis.

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