The cost of whole-genome bisulfite sequencing (WGBS) remains a bottleneck for many studies and it is therefore imperative to extract as much information as possible from a given dataset. This is ...particularly important because even at the recommend 30X coverage for reference methylomes, up to 50% of high-resolution features such as differentially methylated positions (DMPs) cannot be called with current methods as determined by saturation analysis. To address this limitation, we have developed a tool that dynamically segments WGBS methylomes into blocks of comethylation (COMETs) from which lost information can be recovered in the form of differentially methylated COMETs (DMCs). Using this tool, we demonstrate recovery of ∼30% of the lost DMP information content as DMCs even at very low (5X) coverage. This constitutes twice the amount that can be recovered using an existing method based on differentially methylated regions (DMRs). In addition, we explored the relationship between COMETs and haplotypes in lymphoblastoid cell lines of African and European origin. Using best fit analysis, we show COMETs to be correlated in a population-specific manner, suggesting that this type of dynamic segmentation may be useful for integrated (epi)genome-wide association studies in the future.
BAHD1 is a vertebrate protein that promotes heterochromatin formation and gene repression in association with several epigenetic regulators. However, its physiological roles remain unknown. Here, we ...demonstrate that ablation of the Bahd1 gene results in hypocholesterolemia, hypoglycemia and decreased body fat in mice. It also causes placental growth restriction with a drop of trophoblast glycogen cells, a reduction of fetal weight and a high neonatal mortality rate. By intersecting transcriptome data from murine Bahd1 knockout (KO) placentas at stages E16.5 and E18.5 of gestation, Bahd1-KO embryonic fibroblasts, and human cells stably expressing BAHD1, we also show that changes in BAHD1 levels alter expression of steroid/lipid metabolism genes. Biochemical analysis of the BAHD1-associated multiprotein complex identifies MIER proteins as novel partners of BAHD1 and suggests that BAHD1-MIER interaction forms a hub for histone deacetylases and methyltransferases, chromatin readers and transcription factors. We further show that overexpression of BAHD1 leads to an increase of MIER1 enrichment on the inactive X chromosome (Xi). In addition, BAHD1 and MIER1/3 repress expression of the steroid hormone receptor genes ESR1 and PGR, both playing important roles in placental development and energy metabolism. Moreover, modulation of BAHD1 expression in HEK293 cells triggers epigenetic changes at the ESR1 locus. Together, these results identify BAHD1 as a core component of a chromatin-repressive complex regulating placental morphogenesis and body fat storage and suggest that its dysfunction may contribute to several human diseases.
Phylogenetic analysis of the endo-beta-1,4-glucanase gene family of Arabidopsis and other plants revealed a clear distinction in three subfamilies (alpha, beta, and gamma). The alpha- and ...beta-subfamily contains proteins believed to be involved in a number of physiological roles such as elongation, ripening, and abscission. The gamma-subfamily is composed of proteins that are predicted to have a membrane-spanning domain and to be localized at the plasma membrane. Some of these proteins have been linked to cellulose biosynthesis by serving to hydrolyze a lipid-linked intermediate that acts as a primer for the elongation of beta-glucan chains during cellulose synthesis at the plasma membrane. Similar glucanases are important in cellulose biosynthesis in bacteria. Searches in the genomes of unrelated organisms that make cellulose, such as Ciona intestinalis and Dictyostelium discoideum, revealed the presence of membrane-linked endo-beta-1,4-glucanases and it is suggested that these might also have a role in cellulose synthesis. PUBLICATION ABSTRACT
Molecular analyses such as whole-genome sequencing have become routine and are expected to be transformational for future healthcare and lifestyle decisions. Population-wide implementation of such ...analyses is, however, not without challenges, and multiple studies are ongoing to identify what these are and explore how they can be addressed.
Defined as a research project, the Personal Genome Project UK (PGP-UK) is part of the global PGP network and focuses on open data sharing and citizen science to advance and accelerate personalized genomics and medicine.
Here we report our findings on using an open consent recruitment protocol, active participant involvement, open access release of personal genome, methylome and transcriptome data and associated analyses, including 47 new variants predicted to affect gene function and innovative reports based on the analysis of genetic and epigenetic variants. For this pilot study, we recruited 10 participants willing to actively engage as citizen scientists with the project. In addition, we introduce Genome Donation as a novel mechanism for openly sharing previously restricted data and discuss the first three donations received. Lastly, we present GenoME, a free, open-source educational app suitable for the lay public to allow exploration of personal genomes.
Our findings demonstrate that citizen science-based approaches like PGP-UK have an important role to play in the public awareness, acceptance and implementation of genomics and personalized medicine.
Abstract
Epigenetic research has brought several important technological achievements, including identifying epigenetic clocks and signatures, and developing epigenetic editing. The potential ...military applications of such technologies we discuss are stratifying soldiers’ health, exposure to trauma using epigenetic testing, information about biological clocks, confirming child soldiers’ minor status using epigenetic clocks, and inducing epigenetic modifications in soldiers. These uses could become a reality. This article presents a comprehensive literature review, and analysis by interdisciplinary experts of the scientific, legal, ethical, and societal issues surrounding epigenetics and the military. Notwithstanding the potential benefit from these applications, our findings indicate that the current lack of scientific validation for epigenetic technologies suggests a careful scientific review and the establishment of a robust governance framework before consideration for use in the military. In this article, we highlight general concerns about the application of epigenetic technologies in the military context, especially discrimination and data privacy issues if soldiers are used as research subjects. We also highlight the potential of epigenetic clocks to support child soldiers’ rights and ethical questions about using epigenetic engineering for soldiers’ enhancement and conclude with considerations for an ethical framework for epigenetic applications in the military, defense, and security contexts.
BAH domain-containing protein 1 (BAHD1) is involved in heterochromatin formation and gene repression in human cells. BAHD1 also localizes to the inactive X chromosome (Xi), but the functional ...significance of this targeting is unknown. So far, research on this protein has been hampered by its low endogenous abundance and its role in epigenetic regulation remains poorly explored. In this work, we used whole-genome bisulfite sequencing (BS-seq) to compare the DNA methylation profile of HEK293 cells expressing low levels of BAHD1 (HEK-CT) to that of isogenic cells stably overexpressing BAHD1 (HEK-BAHD1). We show that increasing BAHD1 levels induces de novo DNA methylation on autosomes and a marked hypomethylation on the X chromosome (chrX). We identified 91,358 regions that have different methylation patterns in HEK-BAHD1 compared to HEK-CT cells (termed "BAHD1-DMRs"), of which 83,850 mapped on autosomes and 7508 on the X chromosome (chrX). Autosomal BAHD1-DMRs were predominantly hypermethylated and located to satellites, interspersed repeats, and intergenic regions. In contrast, BAHD1-DMRs on chrX were mainly hypomethylated and located to gene bodies and enhancers. We further found that BAHD1-DMRs display a higher-order organization by being clustered within large chromosomal domains. Half of these "BAHD1-Associated differentially methylated Domains" (BADs) overlapped with lamina-associated domains (LADs). Based on these results, we propose that BAHD1-mediated heterochromatin formation is linked to DNA methylation and may play a role in the spatial architecture of the genome.
Phylogenetic analysis of the endo-beta-1,4-glucanase gene family of Arabidopsis and other plants revealed a clear distinction in three subfamilies (alpha, beta, and gamma). The alpha- and ...beta-subfamily contains proteins believed to be involved in a number of physiological roles such as elongation, ripening, and abscission. The gamma-subfamily is composed of proteins that are predicted to have a membrane-spanning domain and to be localized at the plasma membrane. Some of these proteins have been linked to cellulose biosynthesis by serving to hydrolyze a lipid-linked intermediate that acts as a primer for the elongation of beta-glucan chains during cellulose synthesis at the plasma membrane. Similar glucanases are important in cellulose biosynthesis in bacteria. Searches in the genomes of unrelated organisms that make cellulose, such as Ciona intestinalis and Dictyostelium discoideum, revealed the presence of membrane-linked endo-beta-1,4-glucanases and it is suggested that these might also have a role in cellulose synthesis.
The jasmonate (JA)-dependent signalling gene network in Arabidopsis thaliana differentially regulates responses to biotic (e.g. pathogens, wounding) and abiotic (e.g. drought) stress. In this study, ...three transcriptional networks using gene expression data (a large data set of microarray experiments) have been constructed in order to model the interactions between individual genes. The modelling procedures make use of gene co-expression signatures measured by partial correlation. This study presents the novel idea of integrating these signatures by generating edges between two genes in the network on the basis of profiles of partial correlations to a curated set of genes known to be involved in the response. The networks assess the interactions between regulators in the JA pathway and their cross-talk with other hormone-dependent pathways. The results confirm previously known relationships between genes based on experimental evidence and highlight additional connections to test experimentally. This method gives new insights for the discovery of novel genes in the transcriptional coordination of the JA signalling pathway.
BAH domain-containing protein 1 (BAHD1) is involved in heterochromatin formation and gene repression in human cells. BAHD1 also localizes to the inactive X chromosome (Xi), but the functional ...significance of this targeting is unknown. So far, research on this protein has been hampered by its low endogenous abundance and its role in epigenetic regulation remains poorly explored. In this work, we used whole-genome bisulfite sequencing (BS-seq) to compare the DNA methylation profile of HEK293 cells expressing low levels of BAHD1 (HEK-CT) to that of isogenic cells stably overexpressing BAHD1 (HEK-BAHD1). We show that increasing BAHD1 levels induces de novo DNA methylation on autosomes and a marked hypomethylation on the X chromosome (chrX). We identified 91,358 regions that have different methylation patterns in HEK-BAHD1 compared to HEK-CT cells (termed "BAHD1-DMRs"), of which 83,850 mapped on autosomes and 7508 on the X chromosome (chrX). Autosomal BAHD1-DMRs were predominantly hypermethylated and located to satellites, interspersed repeats, and intergenic regions. In contrast, BAHD1-DMRs on chrX were mainly hypomethylated and located to gene bodies and enhancers. We further found that BAHD1-DMRs display a higher-order organization by being clustered within large chromosomal domains. Half of these "BAHD1-Associated differentially methylated Domains" (BADs) overlapped with lamina-associated domains (LADs). Based on these results, we propose that BAHD1-mediated heterochromatin formation is linked to DNA methylation and may play a role in the spatial architecture of the genome.
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