scholarly journals Epigenetic modification associated with climate regulates betulin biosynthesis in birch

2021 ◽  
Author(s):  
Jiang Wang ◽  
Bowei Chen ◽  
Shahid Ali ◽  
Tianxu Zhang ◽  
Yu Wang ◽  
...  
Keyword(s):  
Climate Change ◽  
Dna Methylation ◽  
Climatic Factors ◽  
Epigenetic Modification ◽  
Summer Precipitation ◽  
Dependent Manner ◽  
White Birch ◽  
Environmental Signals ◽  
Pentacyclic Triterpenoid

AbstractThe Betula genus contains pentacyclic triterpenoid betulin known for its environmental adaptation and medicinal properties. However, the mechanisms underlying betulin biosynthesis responding to climate change remain unclear. In this study, the role of epigenetic modification (DNA methylation) in betulin biosynthesis was examined and how climatic factors influence it. Whole-genome bisulfite sequencing was performed for greenhouse-grown Chinese white birch (Betula platyphylla Sukaczev) treated with DNA methylation inhibitor zebularine (ZEB) and a natural birch population in Northeast China. ZEB treatment significantly affected the CHH methylation level of transposable elements and betulin content in a hormesis dose-dependent manner. The methylation and expression of bHLH9, a key transcriptional factor controlling betulin biosynthesis, were also consistently affected by ZEB treatment as a hormetic dose–response. In the natural population, there was a positive correlation between promoter methylation of bHLH9 and summer precipitation, while winter temperature was negatively correlated. Thus climate-dependent methylation of bHLH9 regulates the expression of downstream genes involved in betulin biosynthesis. This study highlights the role of environmental signals to induce epigenetic changes that result in betulin production, possibly helping to develop resilient plants to combat ongoing climate change and enhance secondary metabolite production.

scholarly journals A meta-analysis of the literature on climate change and migration

2021 ◽  
pp. 1-52
Author(s):  
Michel Beine ◽  
Lionel Jeusette
Keyword(s):  
Climate Change ◽  
Climatic Factors ◽  
Human Mobility ◽  
Meta Analysis ◽  
Empirical Studies ◽  
Displacement Effect ◽  
Methodological Choices ◽  
Econometric Methods ◽  
And Migration

Abstract Recent surveys of the literature on climate change and migration emphasize the important diversity of outcomes and approaches of the empirical studies. In this paper, we conduct a meta-analysis in order to investigate the role of the methodological choices of these empirical studies in finding some particular results concerning the role of climatic factors as drivers of human mobility. We code 51 papers representative of the literature in terms of methodological approaches. This results in the coding of more than 85 variables capturing the methodology of the main dimensions of the analysis at the regression level. These dimensions include authors' reputation, type of mobility, measures of mobility, type of data, context of the study, econometric methods, and last but not least measures of the climatic factors. We look at the influence of these characteristics on the probability of finding any effect of climate change, a displacement effect, an increase in immobility, and evidence in favor of a direct vs. an indirect effect. Our results highlight the role of some important methodological choices, such as the frequency of the data on mobility, the level of development, the measures of human mobility and of the climatic factors as well as the econometric methodology.

scholarly journals DNA Methyltransferase 3A Is Involved in the Sustained Effects of Chronic Stress on Synaptic Functions and Behaviors

2020 ◽  
Author(s):  
Jing Wei ◽  
Jia Cheng ◽  
Nicholas J Waddell ◽  
Zi-Jun Wang ◽  
Xiaodong Pang ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Dna Methyltransferase ◽  
Epigenetic Modification ◽  
Substantial Reduction ◽  
Dna Methyltransferases ◽  
Male Rats ◽  
Neural Pathways ◽  
Dnmt Inhibitors ◽  
Synaptic Functions

Abstract Emerging evidence suggests that epigenetic mechanisms regulate aberrant gene transcription in stress-associated mental disorders. However, it remains to be elucidated about the role of DNA methylation and its catalyzing enzymes, DNA methyltransferases (DNMTs), in this process. Here, we found that male rats exposed to chronic (2-week) unpredictable stress exhibited a substantial reduction of Dnmt3a after stress cessation in the prefrontal cortex (PFC), a key target region of stress. Treatment of unstressed control rats with DNMT inhibitors recapitulated the effect of chronic unpredictable stress on decreased AMPAR expression and function in PFC. In contrast, overexpression of Dnmt3a in PFC of stressed animals prevented the loss of glutamatergic responses. Moreover, the stress-induced behavioral abnormalities, including the impaired recognition memory, heightened aggression, and hyperlocomotion, were partially attenuated by Dnmt3a expression in PFC of stressed animals. Finally, we found that there were genome-wide DNA methylation changes and transcriptome alterations in PFC of stressed rats, both of which were enriched at several neural pathways, including glutamatergic synapse and microtubule-associated protein kinase signaling. These results have therefore recognized the potential role of DNA epigenetic modification in stress-induced disturbance of synaptic functions and cognitive and emotional processes.

scholarly journals Tracing livelihood trajectories: Patterns of livelihood adaptations in rural communities in eastern Nepal

2019 ◽  
Vol 12 ◽  
pp. 57-80
Author(s):  
Phu Doma Lama ◽  
Per Becker ◽  
Johan Bergström
Keyword(s):  
Climate Change ◽  
Rural Communities ◽  
Climatic Factors ◽  
Sustainable Livelihood ◽  
Economic Changes ◽  
Mountain Communities ◽  
Rural Livelihood ◽  
Starting Point ◽  
Political Economic

Mountain communities are adapting their livelihoods to a complex combination of social, political and economic changes and associated risks. Despite recognition of adaption in response to multiple changes in sustainable livelihood and critical climate change literature, risks attributed to biophysical effects of climate change have increasingly assumed importance. Consequently, diversification is promoted as an adaptive approach to reduce such risks. However, understanding livelihood adaptation from the vantage point of climate change alone might lead to a limited understanding of non-climatic factors also shaping it. This paper proposes understanding adaptation through analysing long-term livelihood changes and using society rather than climate change as a conceptual starting point. It argues that such an approach has better potential to highlight a broader range of dynamic drivers operating over decades and to inform contextually grounded rural livelihood adaptation policies. Changes are traced in the overall livelihood trajectories among four rural communities in Nepal, in living memory, to understand the role of adaptation in shaping it. Qualitative life narratives were collected and complemented by key informant interviews, field observations and the analysis of official documents. The findings suggest that livelihoods have shifted not only from subsistence towards income generation but also from engagement in diverse livelihood sectors towards specialisation; the opposite of the advocated diversification. The role of political, economic, social and cultural processes within and outside the community has been prominent in shaping this trajectory.

scholarly journals DNA Methylation: A Promising Approach in Management of Alzheimer’s Disease and Other Neurodegenerative Disorders

Biology ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 90
Author(s):  
Gagandeep Kaur ◽  
Suraj Singh S. Rathod ◽  
Mohammed M. Ghoneim ◽  
Sultan Alshehri ◽  
Javed Ahmad ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Dna Methylation ◽  
Neurodegenerative Diseases ◽  
Epigenetic Modification ◽  
Research Area ◽  
Potential Biomarker ◽  
Novel Biomarkers ◽  
Different Populations

DNA methylation, in the mammalian genome, is an epigenetic modification that involves the transfer of a methyl group on the C5 position of cytosine to derive 5-methylcytosine. The role of DNA methylation in the development of the nervous system and the progression of neurodegenerative diseases such as Alzheimer’s disease has been an interesting research area. Furthermore, mutations altering DNA methylation affect neurodevelopmental functions and may cause the progression of several neurodegenerative diseases. Epigenetic modifications in neurodegenerative diseases are widely studied in different populations to uncover the plausible mechanisms contributing to the development and progression of the disease and detect novel biomarkers for early prognosis and future pharmacotherapeutic targets. In this manuscript, we summarize the association of DNA methylation with the pathogenesis of the most common neurodegenerative diseases, such as, Alzheimer’s disease, Parkinson’s disease, Huntington diseases, and amyotrophic lateral sclerosis, and discuss the potential of DNA methylation as a potential biomarker and therapeutic tool for neurogenerative diseases.

scholarly journals Lsh Is Essential for Maintaining Global DNA Methylation Levels in Amphibia and Fish and Interacts Directly with Dnmt1

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Donncha S. Dunican ◽  
Sari Pennings ◽  
Richard R. Meehan
Keyword(s):  
Dna Methylation ◽  
Dna Methyltransferase ◽  
Repetitive Sequences ◽  
Global Dna Methylation ◽  
Dependent Manner ◽  
Gene Promoters ◽  
Cpg Dinucleotides ◽  
Mouse Cells ◽  
Eukaryotic Genomes

Eukaryotic genomes are methylated at cytosine bases in the context of CpG dinucleotides, a pattern which is maintained through cell division by the DNA methyltransferase Dnmt1. Dramatic methylation losses are observed in plant and mouse cells lacking Lsh (lymphoid specific helicase), predominantly at repetitive sequences and gene promoters. However, the mechanism by which Lsh contributes to the maintenance of DNA methylation is unknown. Here we show that DNA methylation is lost in Lsh depleted frog and fish embryos, both of which exhibit developmental delay. Additionally, we show that both Lsh and Dnmt1 are associated with chromatin and that Lsh knockdown leads to a decreased Dnmt1-chromatin association. Coimmunoprecipitation experiments reveal that Lsh and Dnmt1 are found in the same protein complex, and pulldowns show this interaction is direct. Our data indicate that Lsh is usually diffuse in the nucleus but can be recruited to heterochromatin in a HP1α-dependent manner. These data together (a) show that the role of Lsh in DNA methylation is conserved in plants, amphibian, fish, and mice and (b) support a model in which Lsh contributes to Dnmt1 binding to chromatin, explaining how its loss can potentially lead to perturbations in DNA methylation maintenance.

Changes in Lake Area in the Inner Mongolian Plateau under Climate Change: The Role of the Atlantic Multidecadal Oscillation and Arctic Sea Ice

2020 ◽  
Vol 33 (4) ◽  
pp. 1335-1349
Author(s):  
Yong Liu ◽  
Huopo Chen ◽  
Guoqing Zhang ◽  
Jianqi Sun ◽  
Hua Li ◽  
...  
Keyword(s):  
Climate Change ◽  
Sea Ice ◽  
Summer Precipitation ◽  
Atlantic Multidecadal Oscillation ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Lake Area ◽  
Mongolian Plateau ◽  
Arctic Sea

AbstractThe lake area in the Inner Mongolian Plateau (IMP) has experienced a rapid reduction in recent decades. Previous studies have highlighted the important role of intensive human activities in IMP lake shrinkage. However, this study found that climate change–induced summer precipitation variations can exert great influences on the IMP lake area variations. The results suggest that the decadal shift in the IMP summer precipitation may be the predominant contributor to lake shrinkage. Further analysis reveals that the Atlantic multidecadal oscillation (AMO) and Arctic sea ice concentration (SIC) play important roles in the IMP summer precipitation variations. The AMO seems to provide beneficial large-scale circulation fields for the decadal variations in the IMP summer precipitation, and the Arctic SIC decline is favorable for weakening the IMP summer precipitation intensity after the late 1990s. Evidence indicates that the vorticity advection related to the Arctic SIC decline can result in the generation of Rossby wave resources in the midlatitudes. Then, the strengthened wave resources become favorable for enhancing the stationary wave propagation across Eurasia and inducing cyclonic circulation over the Mongolia–Baikal regions, which might bring more rainfall northward and weaken the IMP summer precipitation intensity. Consequently, due to the decreased rainfall and gradual warming after the late 1990s, the lake area in the IMP has experienced a downward trend in recent years.

scholarly journals Apple B-box factors regulate light-responsive anthocyanin biosynthesis genes

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Blue J. Plunkett ◽  
Rebecca Henry-Kirk ◽  
Adam Friend ◽  
Robert Diack ◽  
Susanne Helbig ◽  
...  
Keyword(s):  
Anthocyanin Biosynthesis ◽  
Dependent Manner ◽  
Fruit Colour ◽  
Temperature Dependent ◽  
Environmental Signals ◽  
Over Expression ◽  
Ethylene Content ◽  
Environmentally Responsive ◽  
Anthocyanin Biosynthetic Genes

AbstractEnvironmentally-responsive genes can affect fruit red colour via the activation of MYB transcription factors. The apple B-box (BBX) gene, BBX33/CONSTANS-like 11 (COL11) has been reported to influence apple red-skin colour in a light- and temperature-dependent manner. To further understand the role of apple BBX genes, other members of the BBX family were examined for effects on colour regulation. Expression of 23 BBX genes in apple skin was analysed during fruit development. We investigated the diurnal rhythm of expression of the BBX genes, the anthocyanin biosynthetic genes and a MYB activator, MYB10. Transactivation assays on the MYB10 promoter, showed that BBX proteins 1, 17, 15, 35, 51, and 54 were able to directly function as activators. Using truncated versions of the MYB10 promoter, a key region was identified for activation by BBX1. BBX1 enhanced the activation of MYB10 and MdbHLH3 on the promoter of the anthocyanin biosynthetic gene DFR. In transformed apple lines, over-expression of BBX1 reduced internal ethylene content and altered both cyanidin concentration and associated gene expression. We propose that, along with environmental signals, the control of MYB10 expression by BBXs in ‘Royal Gala’ fruit involves the integration of the expression of multiple BBXs to regulate fruit colour.

scholarly journals A role for LSH in facilitating DNA methylation by DNMT1 through enhancing UHRF1 chromatin association

2020 ◽  
Vol 48 (21) ◽  
pp. 12116-12134
Author(s):  
Mengmeng Han ◽  
Jialun Li ◽  
Yaqiang Cao ◽  
Yuanyong Huang ◽  
Wen Li ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Replication Fork ◽  
De Novo ◽  
Embryonic Stem ◽  
Dna Helicase ◽  
Dependent Manner ◽  
Essential Factor ◽  
Activity Dependent ◽  
Insight Into

Abstract LSH, a SNF2 family DNA helicase, is a key regulator of DNA methylation in mammals. How LSH facilitates DNA methylation is not well defined. While previous studies with mouse embryonic stem cells (mESc) and fibroblasts (MEFs) derived from Lsh knockout mice have revealed a role of Lsh in de novo DNA methylation by Dnmt3a/3b, here we report that LSH contributes to DNA methylation in various cell lines primarily by promoting DNA methylation by DNMT1. We show that loss of LSH has a much bigger effect in DNA methylation than loss of DNMT3A and DNMT3B. Mechanistically, we demonstrate that LSH interacts with UHRF1 but not DNMT1 and facilitates UHRF1 chromatin association and UHRF1-catalyzed histone H3 ubiquitination in an ATPase activity-dependent manner, which in turn promotes DNMT1 recruitment to replication fork and DNA methylation. Notably, UHRF1 also enhances LSH association with the replication fork. Thus, our study identifies LSH as an essential factor for DNA methylation by DNMT1 and provides novel insight into how a feed-forward loop between LSH and UHRF1 facilitates DNMT1-mediated maintenance of DNA methylation in chromatin.

scholarly journals The Role of Host Cell DNA Methylation in the Immune Response to Bacterial Infection

2021 ◽  
Vol 12 ◽  
Author(s):  
Wanhai Qin ◽  
Brendon P. Scicluna ◽  
Tom van der Poll
Keyword(s):  
Dna Methylation ◽  
Immune Response ◽  
Bacterial Infection ◽  
Epigenetic Modification ◽  
Dna Methyltransferases ◽  
Host Cells ◽  
Regulate Gene Expression ◽  
Transcriptional Reprogramming ◽  
Methylation Patterns

Host cells undergo complex transcriptional reprogramming upon infection. Epigenetic changes play a key role in the immune response to bacteria, among which DNA modifications that include methylation have received much attention in recent years. The extent of DNA methylation is well known to regulate gene expression. Whilst historically DNA methylation was considered to be a stable epigenetic modification, accumulating evidence indicates that DNA methylation patterns can be altered rapidly upon exposure of cells to changing environments and pathogens. Furthermore, the action of proteins regulating DNA methylation, particularly DNA methyltransferases and ten-eleven translocation methylcytosine dioxygenases, may be modulated, at least in part, by bacteria. This review discusses the principles of DNA methylation, and recent insights about the regulation of host DNA methylation during bacterial infection.

scholarly journals Adiponectin Related Vascular and Cardiac Benefits in Obesity: Is There a Role for an Epigenetically Regulated Mechanism?

2021 ◽  
Vol 8 ◽  
Author(s):  
Rosaria Anna Fontanella ◽  
Lucia Scisciola ◽  
Maria Rosaria Rizzo ◽  
Surina Surina ◽  
Celestino Sardu ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Blood Cells ◽  
Epigenetic Modification ◽  
Surrogate Marker ◽  
Left Ventricular ◽  
Epigenetic Modifications ◽  
Left Ventricular Ejection ◽  
Ventricular Ejection Fraction ◽  
Plasma Mirna

In obesity, several epigenetic modifications, including histones remodeling, DNA methylation, and microRNAs, could accumulate and determine increased expression of inflammatory molecules, the adipokines, that in turn might induce or accelerate the onset and development of cardiovascular and metabolic disorders. In order to better clarify the potential epigenetic mechanisms underlying the modulation of the inflammatory response by adipokines, the DNA methylation profile in peripheral leukocytes of the promoter region of IL-6 and NF-kB genes and plasma miRNA-21 levels were evaluated in 356 healthy subjects, using quantitative pyrosequencing-based analysis, and correlated with plasma adiponectin levels, body fat content and the primary pro-inflammatory markers. In addition, correlation analysis of DNA methylation profiles and miRNA-21 plasma levels with intima-media thickness (IMT), a surrogate marker for early atherosclerosis, left ventricular mass (LVM), left ventricular ejection fraction (LVEF), and cardiac performance index (MPI) was also performed to evaluate any potential clinical implication in terms of cardiovascular outcome. Results achieved confirmed the role of epigenetics in the obesity-related cardiovascular complications and firstly supported the potential role of plasma miRNA-21 and IL-6 and NF-kB DNA methylation changes in nucleated blood cells as potential biomarkers for predicting cardiovascular risk in obesity. Furthermore, our results, showing a role of adiponectin in preventing epigenetic modification induced by increased adipose tissue content in obese subjects, provide new evidence of an additional mechanism underlying the anti-inflammatory properties and the cardiovascular benefits of adiponectin. The exact mechanisms underlying the obesity-related epigenetic modifications found in the blood cells and whether similar epigenetic changes reflect adipose and myocardial tissue modifications need to be further investigated in future experiments.

Sign in / Sign up

Export Citation Format

Share Document