Maternal Nutrition Induces Pervasive Gene Expression Changes but no Detectable DNA Methylation Differences in the Liver of Adult Offspring
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: David Serre
PROVIDER: E-GEOD-52268 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Aims: Epidemiological and animal studies have shown that maternal diet can influence metabolism in adult offspring. However, the molecular mechanisms underlying these changes remain poorly understood. Here, we aim to explore phenotypes induced by maternal obesity in a mouse model and examine gene expression and epigenetic alterations in adulthood induced by maternal diet. Methods: We analyzed genetically identical male mice born from dams fed a high- or low-fat diet throughout pregnancy and until day 21 postpartum. After weaning, half of the males of each group were fed a high-fat diet, the other half a low-fat diet. We first characterized the genome-wide gene expression patterns of six tissues of adult offspring - liver, pancreas, white adipose, brain, muscle and heart [GSE40903] . We then measured DNA methylation patterns in liver at selected loci and throughout the genome. Results: Maternal diet had a significant effect on the body weight of the offspring when they are fed an obesogenic diet after weaning. Our analyses showed that maternal diet had a pervasive effect on gene expression, with a pronounced effect in liver where it affected many genes involved in inflammation, cholesterol synthesis and RXR activation. Maternal diet had no detectable effect on DNA methylation in the liver. Conclusions: Overall, our findings highlighted the persistent influence of maternal diet on adult tissue regulation and suggested that the transcriptional changes were unlikely to be caused by DNA methylation differences in adult liver. Methylation is compared between nine week old animals fed a common diet as adults, but derived from mothers fed different diets. Sequence of PCR amplification of bisulfite converted genomic DNA of numerous loci
2014-03-04 | E-GEOD-52267 | biostudies-arrayexpress
Project description:Aims: Epidemiological and animal studies have shown that maternal diet can influence metabolism in adult offspring. However, the molecular mechanisms underlying these changes remain poorly understood. Here, we aim to explore phenotypes induced by maternal obesity in a mouse model and examine gene expression and epigenetic alterations in adulthood induced by maternal diet. Methods: We analyzed genetically identical male mice born from dams fed a high- or low-fat diet throughout pregnancy and until day 21 postpartum. After weaning, half of the males of each group were fed a high-fat diet, the other half a low-fat diet. We first characterized the genome-wide gene expression patterns of six tissues of adult offspring - liver, pancreas, white adipose, brain, muscle and heart [GSE40903] . We then measured DNA methylation patterns in liver at selected loci and throughout the genome. Results: Maternal diet had a significant effect on the body weight of the offspring when they are fed an obesogenic diet after weaning. Our analyses showed that maternal diet had a pervasive effect on gene expression, with a pronounced effect in liver where it affected many genes involved in inflammation, cholesterol synthesis and RXR activation. Maternal diet had no detectable effect on DNA methylation in the liver. Conclusions: Overall, our findings highlighted the persistent influence of maternal diet on adult tissue regulation and suggested that the transcriptional changes were unlikely to be caused by DNA methylation differences in adult liver. Methylation is compared between nine week old animals fed a common diet as adults, but derived from mothers fed different diets.
2014-03-04 | E-GEOD-52266 | biostudies-arrayexpress
Project description:In plants, imprinted gene expression occurs in endosperm seed tissue and can be associated with differential DNA methylation between maternal and paternal alleles. Imprinting is theorized to have been selected for because of conflict between parental genomes in offspring, but most studies of imprinting have been conducted in Arabidopsis thaliana, an inbred primarily self-fertilizing species that should have limited parental conflict. We examined embryo and endosperm allele-specific expression and DNA methylation genome-wide in the wild outcrossing species Arabidopsis lyrata. Here we show that the majority of A. lyrata imprinted genes exhibit parentally-biased expression in A. thaliana, suggesting that there is evolutionary conservation in gene imprinting. Surprisingly, we discovered substantial interspecies differences in methylation features associated with paternally expressed imprinted genes (PEGs). Unlike A. thaliana, the maternal allele of many A. lyrata PEGs was hypermethylated in the CHG context. Increased maternal allele CHG methylation was associated with increased expression bias in favor of the paternal allele. We propose that CHG methylation maintains or reinforces repression of maternal alleles of PEGs. These data suggest that while the genes subject to imprinting are largely conserved, there is flexibility in the epigenetic mechanisms employed between closely related species to maintain monoallelic expression. This supports the idea that imprinting of specific genes is a functional phenomenon, and not simply a byproduct of seed epigenomic reprogramming. Examination of total gene expression, parent-of-origin specific allelic bias, or DNA methylation in embryo, endosperm, flower bud or seedcoat tissue from Arabidopsis lyrata accessions MN47 (MN), Karhumaki (Kar or KA), and crosses between them. High-throughput Illumina poly-A-selected mRNA-seq was used to identify imprinted genes in A. lyrata, and high-throughput Illumina whole genome bisulfite-sequencing was used to examine DNA methylation. mRNA-seq samples are designated MMxFF_T# where MM is the mother of the cross (either MN for MN47 or KA for Kar), FF is the father, T is the tissue (E for embryo, N for endosperm, S for seedcoat, b for buds), and # is the replicate numbers. Samples obtained from bisulfite sequencing follow the same naming but have suffix _BS and indicate cytosine methylation context (CpG, CHG, or CHH). For KAxMN bisulfite sequencing, additional files MMxFF_T#_BS_P_C.txt follow the same naming scheme but contain context-specific methylation data (C) from reads that mapped preferentially to one parent strain (P).
2016-09-01 | E-GEOD-76076 | biostudies-arrayexpress
Project description:In plants, RNA polymerase II (Pol II) transcription of inverted DNA repeats produces hairpin RNAs that are processed by several DICER-LIKE enzymes into siRNAs that are 21-24-nt in length. When targeted to transcriptional regulatory regions, the 24-nt size class can induce RNA-directed DNA methylation (RdDM) and transcriptional gene silencing (TGS). In a forward genetic screen to identify mutants defective in RdDM of a target enhancer leading to TGS of a downstream GFP reporter gene in Arabidopsis thaliana, we recovered a structurally mutated silencer locus, named SM-NM-^T35S, in which the 35S promoter driving transcription of an inverted repeat of target enhancer sequences had been specifically deleted. Although Pol II-dependent, hairpin-derived 21-24-nt siRNAs were no longer generated at the newly created SM-NM-^T35S locus, the GFP reporter gene was nevertheless still partially silenced. Silencing was associated with methylation in a short tandem repeat in the upstream target enhancer and with low levels of 24-nt tandem repeat siRNAs. Introducing an nrpd1 mutation into the SM-NM-^T35S line fully released GFP silencing and eliminated both the tandem repeat methylation and associated 24-nt siRNAs, demonstrating their dependence on Pol IV. Deletion of the 35S promoter thus revealed a Pol IV-dependent pathway of 24-nt siRNA biogenesis that was previously inhibited or masked by the Pol II-dependent pathway in wild-type plants. Both Pol II- and Pol IV-dependent siRNAs accrued predominantly from cytosine (C)-containing segments of the tandem repeat monomer, suggesting that the local base composition influenced siRNA accumulation. Preferential accumulation of siRNAs at C-containing sequences was also observed at an endogenous tandem repeat comprising discrete C-rich and AT-rich sections. Our studies illuminate the potential complexity of siRNA generation at repeat-containing loci and show that Pol IV can act in siRNA biogenesis in the absence of a conventional Pol II promoter. Examination of whole-genome DNA methylation status in transgenic T+S Arabidopsis plant
2013-05-30 | E-GEOD-47453 | biostudies-arrayexpress
Project description:Alternative splicing is prevalent in plants, but little is known about its regulation in the context of developmental and signaling pathways. We describe here a new factor that influences pre-mRNA splicing and is essential for embryonic development in Arabidopsis thaliana. This factor was retrieved in a genetic screen that identified mutants impaired in expression of an alternatively spliced GFP reporter gene. In addition to the known spliceosomal component PRP8, the screen retrieved a previously uncharacterized protein containing a Replication termination factor2 (Rtf2) domain defined by a C2HC2 zinc finger. The Rtf2 protein was discovered in fission yeast, where it stabilizes paused DNA replication forks by an unknown mechanism. When homozygous, a null mutation in Arabidopsis RTF2 (AtRTF2) is embryo-lethal, indicating that it encodes an essential protein. As revealed by quantitative RT-PCR, impaired expression of GFP in atrtf2 and prp8 mutants is attributable to inefficient splicing of the GFP pre-mRNA. A genome-wide analysis using RNA-seq demonstrated that 12% of total introns display a significant degree of retention in atrtf2 mutants. Intron-retaining transcripts are enriched from genes encoding proteins involved in signaling pathways and membrane transport. Affinity purification of AtRTF2 followed by mass spectrometry identified several known and predicted splicing proteins. In a yeast two-hybrid screen, AtRTF2 interacted with Exo70B1, a peripheral subunit of the exocyst, which is involved in vesicle trafficking. Considering these results and previous suggestions that Rtf2 constitutes an ubiquitin-related domain, we discuss possible roles of AtRTF2 in ubiquitin-based regulation of pre-mRNA splicing and membrane signaling to the spliceosome. Rtf2 is SDR1 (= AtRTF2) and was discovered in a genetic suppressor screen using the dms4 mutant. DMS4 was described in Kanno et al (2010) EMBO Rep. 11:65-71. Examination of whole-genome DNA methylation status in transgenic Arabidopsis plants
2014-11-14 | E-GEOD-63238 | biostudies-arrayexpress
Project description:Natural epigenetic variation provides a source for the generation of phenotypic diversity, but to understand its contribution to phenotypic diversity, its interaction with genetic variation requires further investigation. MethylC-seq from naturally-occurring Arabidopsis accessions
2013-03-05 | E-GEOD-43857 | biostudies-arrayexpress
Project description:Significant interest has been devoted to the isolation of human pluripotent stem cells displaying the naive state of mouse embryonic stem cells. However, to what extent naive human cells isolated in culture resemble pluripotent cells in vivo remains unclear. Here we present three lines of evidence indicating that naive pluripotent stem cells generated in the absence of transgenes share defining molecular signatures with the human pre-implantation embryo. First, a comprehensive analysis of the transposcriptome reveals that naive human cells have a retroelement expression profile of human cleavage stage embryos. Second, base-resolution mapping of the DNA methylome in naive human cells reveals a genome-wide reduction in CpG and non-CpG methylation levels. Third, female naive cells exhibit an X chromosome status that is similar to that of the human blastocyst. Our work demonstrates that pluripotent stem cells with epigenomic hallmarks of the early human embryo can be directly captured in vitro. Examine the methylomes of 6 naïve, 2 primed and 2 re-primed human embryonic stem cells
2016-07-18 | E-GEOD-75868 | biostudies-arrayexpress
Project description:Tet-mediated DNA oxidation is a new type of epigenetic modification in mammals and its role in the regulation of cell fate transition remains poorly understood. Here, we derive mouse embryonic fibroblasts (MEFs) deleted in all three Tet genes and examine their capability to be reprogrammed into iPS cells. We demonstrate that these Tet-deficient MEFs cannot be reprogrammed due to a blockage in the mesenchymal-to-epithelial transition (MET). Reprogramming of MEFs deficient in TDG is similarly blocked. The blockage is caused by impaired activation of crucial microRNAs, which depends on oxidative demethylation promoted by Tet and TDG. Reintroduction of either miR-200c or catalytically active Tet and TDG restores reprogramming to the respective knockout MEFs. Thus, oxidative demethylation is essential for somatic cell reprogramming. These findings provide mechanistic insights into the operation of epigenetic barriers in cell lineage conversion. Reduced Representation Bisulfite (RRBS, MspI,~75-400bp size fraction) and Tet-Assisted RRBS (TARRBS) of MEFs & reprogramming MEFs at Day 5
2014-02-19 | E-GEOD-52741 | biostudies-arrayexpress
Project description:To characterize the largely unknown functions of oxidised methylcytosines (oxi-mC; 5hmC/5fC/5caC) in DNA, several sequencing protocols have been recently developed. Quantitative analysis is complicated because DNA methylation modifications need to be deconvoluted from the data which is affected by several experimental parameters, including e.g. imperfect bisulphite conversion, oxidation efficiencies, various chemical labeling and protection steps, and sequencing errors. Here, we present a hierarchical generative model, Lux, for integrative analysis of any combination of BS-seq and âoxi-mCâ-seq (BS-seq/oxBS-seq/TAB-seq/fCAB-seq/CAB-seq/redBS-seq/MAB-seq) data. We show that Lux improves quantification and comparison of methylation levels over existing methods and that Lux can easily process any oxi-mC-seq data sets to quantify all cytosine modifications simultaneously together with their experimental parameters. Application of Lux to targeted data from Tet2 knockdown ESCs and T cells during development demonstrates DNA modification quantification at unprecedented detail, quantifies active demethylation pathway and reveals 5hmC localization in putative regulatory regions. Examine the distribution of C, 5mC, and 5hmC in ES and Tet2 knock-down cells within selected loci. Half of the samples are measured using the traditional bisulphite-seq protocol but the other half is measured using the oxidative bisulphite-seq protocol (oxBS-seq).
2016-07-03 | E-GEOD-68574 | biostudies-arrayexpress
Project description:DNA methylation is an epigenetic modification that differs between plant organs and tissues, but the extent of variation between cell types is not known. Here, we report single-base resolution whole genome DNA methylomes, mRNA transcriptomes, and small RNA transcriptomes for six cell populations covering the major cell types of the Arabidopsis root meristem. We identify widespread cell type specific patterns of DNA methylation, especially in the CHH sequence context. The genome of the columella root cap is the most highly methylated Arabidopsis cell characterized to date. It is hypermethylated within transposable elements, accompanied by increased abundance of transcripts encoding RNA-directed DNA methylation (RdDM) pathway components and 24 nt small RNAs. Absence of the nucleosome remodeler DECREASED DNA METHYLATION 1, required for maintenance of DNA methylation, and low abundance of histone transcripts involved in heterochromatin formation suggests a loss of heterochromatin may occur in the columella, thus allowing access of RdDM factors to the whole genome, and producing excess 24 nt small RNAs in this tissue. Together, these maps provide new insights into the epigenomic diversity that exists between distinct plant somatic cell types. MethylC-seq from six cell populations covering the major cell types of the Arabidopsis root meristem.
2016-03-31 | E-GEOD-79708 | biostudies-arrayexpress