Project description:We report the application of methylacytosine immunoprecipetation combined with Illumina sequencing (MeDIP-seq) for high-throughput profiling of DNA methylation in rice embryo 3, 6, 9 DAP and endosperm 2, 3, 6, 9 DAP. A total number of 12-14 million of 2×49 bp paired-end reads was generated for each sample, and BOWTIE2 was used for read mapping. We generated genome-wide DNA methylation profiles of rice embryo and endosperm. This study provides a framework to systemically characterize the effect of DNA methylation in developing seeds and will help to illustrate the epigenetic regulation of rice seed development. Rice embryo and endosperm were selected for DNA extraction and methylacytosine immunoprecipetation combined with Illumina sequencing. We sought to obtain the genome-wide DNA methylation profilings of embryo at 3,6,9 days after pollination(DAP) and endosperm at 2,3,6,9 DAP. To that end, we hand-selected embryo at 3,6,9 DAP and endosperm at 2,3,6,9 DAP according to morphological criteria.
Project description:Epigenetic modification plays important roles in plant and animal development. DNA methylation can impact the transposable element (TE) silencing, gene imprinting and regulate gene expression.Through a genome-wide analysis, DNA methylation peaks were respectively characterized and mapped in maize embryo and endosperm genome. Distinct methylation level across maize embryo and endosperm was observed. The maize embryo genome contained more DNA methylation peaks than endosperm. However, the endosperm chloroplast genome contained more DNA methylation peaks to compare with the embryo chloroplast genome. DNA methylation regions were characterized and mapped in genome. More CG island (CGI) shore are methylated than CGI in maize suggested that DNA methylation level is not positively correlated with CpG density. The DNA methylation occurred more frequently in the promoter sequence and transcriptional termination region (TTR) than other regions of the genes. The result showed that 99% TEs we characterized are methylated in maize embryo, but some (34.8%) of them are not methylated in endosperm. Maize embryo and endosperm exhibit distinct pattern/level of methylation. The most differentially methylated two regions between embryo and endosperm are High CpG content promoters (HCPs) and high CpG content TTRs (HCTTRs). DNA methylation peaks distinction of mitochondria and chloroplast DNA were less than the nucleus DNA. Our results indicated that DNA methylation is associated with the gene silencing or gene activation in maize endosperm and embryo. Many genes involved in embryogenesis and seed development were found differentially methylated in embryo and endosperm. We found 17 endosperm-specific expressed imprinting genes were hypomethylated in endosperm and were hypermethylated in embryo. The expression of a maize DEMETER -like (DME-like) gene and MBD101 gene (MBD4 homolog) which direct bulk genome DNA demethylation were higher in endosperm than in embryo. These two genes may be associated with the distinct methylation level across maize embryo and endosperm.The methylomes of maize embryo and endosperm was obtained by MeDIP-seq method. The global mapping of maize embryo and endosperm methylation in this study broadened our knowledge of DNA methylation patterns in maize genome, and provided useful information for future studies on maize seed development and regulation of metabolic pathways in different seed tissues. Examination of DNA methylated modifications in 2 maize tissues.
Project description:We present genome-scale maps of DNA methylation in early human development and perform comparative analysis to mouse that confirm a conserved global erasure of the paternal genome. We find that while many global features of the early embryo are consistent between the two species, the target sequences in which DNA methylation is maintained are distinct. Repetitive elements show a broader range of class specific behaviors in the human embryo and a larger degree of methylation escape in human sperm. We identify thousands of differentially methylated regions (DMRs) that are likely of maternal origin and found that these gamete contributed DMRs are far more species-specific than expected given the conservation of canonical imprint control regions (ICRs). Finally, we extended our studies to the derivation of new human embryonic stem cell (ESC) lines and found notable divergences in DNA methylation signatures from those found in the human embryo and different mouse ESC derivation conditions. Comparison of DNA methylation patterns in human early development, human ESC derivation and mouse ESC derivation
Project description:DNA methylation data from common marmosets (Callithrix jacchus) profiled on the mammalian methylation array (HorvathMammalMethylChip40) which focuses on highly conserved CpGs across mammalian species. Rapamycin study in a subset of animals.
Project description:We report the application of methylacytosine immunoprecipetation combined with Illumina sequencing (MeDIP-seq) for high-throughput profiling of DNA methylation in rice embryo 3, 6, 9 DAP and endosperm 2, 3, 6, 9 DAP. A total number of 12-14 million of 2×49 bp paired-end reads was generated for each sample, and BOWTIE2 was used for read mapping. We generated genome-wide DNA methylation profiles of rice embryo and endosperm. This study provides a framework to systemically characterize the effect of DNA methylation in developing seeds and will help to illustrate the epigenetic regulation of rice seed development.
Project description:Epigenetic modification plays important roles in plant and animal development. DNA methylation can impact the transposable element (TE) silencing, gene imprinting and regulate gene expression.Through a genome-wide analysis, DNA methylation peaks were respectively characterized and mapped in maize embryo and endosperm genome. Distinct methylation level across maize embryo and endosperm was observed. The maize embryo genome contained more DNA methylation peaks than endosperm. However, the endosperm chloroplast genome contained more DNA methylation peaks to compare with the embryo chloroplast genome. DNA methylation regions were characterized and mapped in genome. More CG island (CGI) shore are methylated than CGI in maize suggested that DNA methylation level is not positively correlated with CpG density. The DNA methylation occurred more frequently in the promoter sequence and transcriptional termination region (TTR) than other regions of the genes. The result showed that 99% TEs we characterized are methylated in maize embryo, but some (34.8%) of them are not methylated in endosperm. Maize embryo and endosperm exhibit distinct pattern/level of methylation. The most differentially methylated two regions between embryo and endosperm are High CpG content promoters (HCPs) and high CpG content TTRs (HCTTRs). DNA methylation peaks distinction of mitochondria and chloroplast DNA were less than the nucleus DNA. Our results indicated that DNA methylation is associated with the gene silencing or gene activation in maize endosperm and embryo. Many genes involved in embryogenesis and seed development were found differentially methylated in embryo and endosperm. We found 17 endosperm-specific expressed imprinting genes were hypomethylated in endosperm and were hypermethylated in embryo. The expression of a maize DEMETER -like (DME-like) gene and MBD101 gene (MBD4 homolog) which direct bulk genome DNA demethylation were higher in endosperm than in embryo. These two genes may be associated with the distinct methylation level across maize embryo and endosperm.The methylomes of maize embryo and endosperm was obtained by MeDIP-seq method. The global mapping of maize embryo and endosperm methylation in this study broadened our knowledge of DNA methylation patterns in maize genome, and provided useful information for future studies on maize seed development and regulation of metabolic pathways in different seed tissues.
Project description:DNA methylation is highly dynamic during mammalian embryogenesis. It is broadly accepted that the paternal genome is actively depleted of global cytosine methylation at fertilization, followed by passive depletion that reaches a minimum at the blastocyst stage. However, this model is based on limited data, and to date no base-resolution maps exist to support and refine it. Here, we generated genome-scale DNA methylation maps in mouse gametes and through post-implantation embryogenesis. We find that the oocyte already exhibits global hypomethylation, most prominently at specific subfamilies of LINE-1 and LTR-containing retro-elements, which are disparate between gametes and resolve to lower methylation values in zygote. Surprisingly, the oocyte contributes a unique set of Differentially Methylated Regions (DMRs), including many CpG Island promoter regions, that are maintained in the early embryo but are lost at the onset of embryonic specification and absent in somatic cells. In contrast, sperm contributed methylation includes retrotransposons that become completely methylated after the blastocyst stage. Our data provide a complete genome-scale, base-resolution timeline of DNA methylation in the pre-specified embryo, when this epigenetic modification is most dynamic and before returning to the canonical somatic pattern. Comparison of DNA methylation patterns in mouse gametes and through embryogenesis using Reduced Representation Bisulfite Sequencing (RRBS)
Project description:We present genome-scale maps of DNA methylation in early human development and perform comparative analysis to mouse that confirm a conserved global erasure of the paternal genome. We find that while many global features of the early embryo are consistent between the two species, the target sequences in which DNA methylation is maintained are distinct. Repetitive elements show a broader range of class specific behaviors in the human embryo and a larger degree of methylation escape in human sperm. We identify thousands of differentially methylated regions (DMRs) that are likely of maternal origin and found that these gamete contributed DMRs are far more species-specific than expected given the conservation of canonical imprint control regions (ICRs). Finally, we extended our studies to the derivation of new human embryonic stem cell (ESC) lines and found notable divergences in DNA methylation signatures from those found in the human embryo and different mouse ESC derivation conditions.