Project description:This SuperSeries is composed of the following subset Series: GSE20714: Broad epigenetic signature of maternal care in the brain of adult rats (DNA methylation and H3K9 acetylation profiles) GSE20717: Broad epigenetic signature of maternal care in the brain of adult rats (expression) Refer to individual Series
Project description:BackgroundMaternal care is associated with long-term effects on behavior and epigenetic programming of the NR3C1 (GLUCOCORTICOID RECEPTOR) gene in the hippocampus of both rats and humans. In the rat, these effects are reversed by cross-fostering, demonstrating that they are defined by epigenetic rather than genetic processes. However, epigenetic changes at a single gene promoter are unlikely to account for the range of outcomes and the persistent change in expression of hundreds of additional genes in adult rats in response to differences in maternal care.Methodology/principal findingsWe examine here using high-density oligonucleotide array the state of DNA methylation, histone acetylation and gene expression in a 7 million base pair region of chromosome 18 containing the NR3C1 gene in the hippocampus of adult rats. Natural variations in maternal care are associated with coordinate epigenetic changes spanning over a hundred kilobase pairs. The adult offspring of high compared to low maternal care mothers show epigenetic changes in promoters, exons, and gene ends associated with higher transcriptional activity across many genes within the locus examined. Other genes in this region remain unchanged, indicating a clustered yet specific and patterned response. Interestingly, the chromosomal region containing the protocadherin-?, -?, and -? (Pcdh) gene families implicated in synaptogenesis show the highest differential response to maternal care.Conclusions/significanceThe results suggest for the first time that the epigenetic response to maternal care is coordinated in clusters across broad genomic areas. The data indicate that the epigenetic response to maternal care involves not only single candidate gene promoters but includes transcriptional and intragenic sequences, as well as those residing distantly from transcription start sites. These epigenetic and transcriptional profiles constitute the first tiling microarray data set exploring the relationship between epigenetic modifications and RNA expression in both protein coding and non-coding regions across a chromosomal locus in the mammalian brain.
Project description:Maternal care is associated with long-term effects on behavior and epigenetic programming of the NR3C1 (GLUCOCORTICOID RECEPTOR) gene in the hippocampus of both rats and humans. However, epigenetic changes at a single gene promoter are unlikely to account for the range of responses to the early life environment and the persistent change in expression of hundreds of additional genes in adult rats in response to differences in maternal care. Here we show that natural variations in maternal care are associated with coordinate changes in DNA methylation, chromatin, and gene expression spanning over a hundred kilobase pairs in the hippocampus of adult rats. The offspring of high compared to low maternal care mothers show epigenetic changes in promoters, exons, and gene ends and higher transcriptional activity across many genes, suggesting that a broad epigenetic regulation of gene expression may form part of a coordinated response to early maternal care. We obtained hippocampal samples from adult offspring of rat mothers that differed in the frequency of pup licking/grooming in the first week of life, 4 from high frequency and 4 from low frequency mothers. Using custom-designed microarrays with probes tiling the 7 million base pair region of rat chromosome 18 centered at the NR3C1 gene at 100 bp spacing, we obtained transcription profiles by hybridizing cDNA to microarrays. Each profile was generated in duplicate.
Project description:Maternal care is associated with long-term effects on behavior and epigenetic programming of the NR3C1 (GLUCOCORTICOID RECEPTOR) gene in the hippocampus of both rats and humans. However, epigenetic changes at a single gene promoter are unlikely to account for the range of responses to the early life environment and the persistent change in expression of hundreds of additional genes in adult rats in response to differences in maternal care. Here we show that natural variations in maternal care are associated with coordinate changes in DNA methylation, chromatin, and gene expression spanning over a hundred kilobase pairs in the hippocampus of adult rats. The offspring of high compared to low maternal care mothers show epigenetic changes in promoters, exons, and gene ends and higher transcriptional activity across many genes, suggesting that a broad epigenetic regulation of gene expression may form part of a coordinated response to early maternal care.
Project description:Maternal care is associated with long-term effects on behavior and epigenetic programming of the NR3C1 (GLUCOCORTICOID RECEPTOR) gene in the hippocampus of both rats and humans. However, epigenetic changes at a single gene promoter are unlikely to account for the range of responses to the early life environment and the persistent change in expression of hundreds of additional genes in adult rats in response to differences in maternal care. Here we show that natural variations in maternal care are associated with coordinate changes in DNA methylation, chromatin, and gene expression spanning over a hundred kilobase pairs in the hippocampus of adult rats. The offspring of high compared to low maternal care mothers show epigenetic changes in promoters, exons, and gene ends and higher transcriptional activity across many genes, suggesting that a broad epigenetic regulation of gene expression may form part of a coordinated response to early maternal care.
Project description:Maternal care is associated with long-term effects on behavior and epigenetic programming of the NR3C1 (GLUCOCORTICOID RECEPTOR) gene in the hippocampus of both rats and humans. However, epigenetic changes at a single gene promoter are unlikely to account for the range of responses to the early life environment and the persistent change in expression of hundreds of additional genes in adult rats in response to differences in maternal care. Here we show that natural variations in maternal care are associated with coordinate changes in DNA methylation, chromatin, and gene expression spanning over a hundred kilobase pairs in the hippocampus of adult rats. The offspring of high compared to low maternal care mothers show epigenetic changes in promoters, exons, and gene ends and higher transcriptional activity across many genes, suggesting that a broad epigenetic regulation of gene expression may form part of a coordinated response to early maternal care. We obtained hippocampal samples from adult offspring of rat mothers that differed in the frequency of pup licking/grooming in the first week of life. Using custom-designed microarrays with probes tiling the 7 million base pair region of rat chromosome 18 centered at the NR3C1 gene at 100 bp spacing, we obtained DNA methylation and H3K9 acetylation profiles by ChIP-on-chip. Each profile was generated in triplicate, each type of profile from 3 high frequency and 3 low frequency mothers.
Project description:Epigenetic changes such as DNA cytosine methylation modulate gene function across brain and are implicated in the pathophysiology of neurodevelopmental disorders including schizophrenia and autism. Epigenetic changes can be caused by environmental exposures such as inflammation, and may at least partly explain why prenatal exposure to inflammation increase risk of neurodevelopmental disorders. We used an MIA mouse model to investigate the postnatal epigenetic changes associated with exposure to the viral analogue PolyI:C. The effect of dietary supplement with omega-3 polyunsaturated fatty acids (PUFA) on exposed mice was also examined. Methylation was estimated genome-wide across gene regulatory regions. Widespread epigenetic changes were observed following exposure to inflammation during prenatal life. The differentially methylated gene set was enriched for genes involved in nervous system development and function. Omega-3 intervention modified the epigenetic profile, including a number of genes which were affected by MIA. These experiments indicate that environmental and genetic risk factors modulate similar biological pathways that are associated with neurodevelopmental disorders.
Project description:BackgroundPreterm birth is a leading cause of perinatal mortality and long-term health consequences. Epigenetic mechanisms may have been at play in preterm birth survivors, and these could be persistent and detrimental to health later in life.MethodsWe performed a genome-wide DNA methylation profiling in adult twins of premature birth to identify genomic regions under differential epigenetic regulation in 144 twins with a median age of 33 years (age range 30-36).ResultsAssociation analysis detected three genomic regions annotated to the SDHAP3, TAGLN3 and GSTT1 genes on chromosomes 5, 3 and 22 (FWER: 0.01, 0.02 and 0.04) respectively. These genes display strong involvement in neurodevelopmental disorders, cancer susceptibility and premature delivery. The three identified significant regions were successfully replicated in an independent sample of twins of even older age (median age 66, range 56-80) with similar regulatory patterns and nominal p values < 5.05e-04. Biological pathway analysis detected five significantly enriched pathways all explicitly involved in immune responses.ConclusionWe have found novel evidence associating premature delivery with epigenetic modification of important genes/pathways and revealed that preterm birth, as an early life event, could be related to differential methylation regulation patterns observable in adults and even at high ages which could potentially mediate susceptibility to age-related diseases and adult health.
Project description:BACKGROUND: A low birth weight has been extensively related to poor adult health outcomes. Birth weight can be seen as a proxy for environmental conditions during prenatal development. Identical twin pairs discordant for birth weight provide an extraordinary model for investigating the association between birth weight and adult life health while controlling for not only genetics but also postnatal rearing environment. We performed an epigenome-wide profiling on blood samples from 150 pairs of adult monozygotic twins discordant for birth weight to look for molecular evidence of epigenetic signatures in association with birth weight discordance. RESULTS: Our association analysis revealed no CpG site with genome-wide statistical significance (FDR < 0.05) for either qualitative (larger or smaller) or quantitative discordance in birth weight. Even with selected samples of extremely birth weight discordant twin pairs, no significant site was found except for 3 CpGs that displayed age-dependent intra-pair differential methylation with FDRs 0.014 (cg26856578, p = 3.42e-08), 0.0256 (cg15122603, p = 1.25e-07) and 0.0258 (cg16636641, p = 2.05e-07). Among the three sites, intra-pair differential methylation increased with age for cg26856578 but decreased with age for cg15122603 and cg16636641. There was no genome-wide statistical significance for sex-dependent effects on intra-pair differential methylation in either the whole samples or the extremely discordant twins. CONCLUSIONS: Genome-wide DNA methylation profiling did not reveal epigenetic signatures of birth weight discordance although some sites displayed age-dependent intra-pair differential methylation in the extremely discordant twin pairs.