Project description:Here we report genome-wide high resolution allele-specific maps of DNA methylation and histone H3 lysine 27 trimethylation (H3K27me3) in maize endosperm. To investigate the allele-specific DNA methylation pattern of maize endosperm on a genome-wide scale, we performed MethylC-seq for shoot, embryo, and endosperm tissue 12 d after pollination (DAP) of inbred B73, and the endosperm tissue 12 DAP of reciprocal crosses B73 Ã Mo17 (BM) and Mo17 Ã B73 (MB). We also performed additional RNA-seq for samples from 12-DAP and 10-DAP endosperm of both reciprocal crosses between inbreds B73 and Mo17
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:The goals of this study are to compare NGS-derived transcriptomes (RNA-Seq) derived from ded1-ref mutant and normal maize endosperm tissue. Homozygous ded1-ref mutants exhibit a seed defect. Maize Ded1 encodes a transcription factor. This study characterizes DEGs between ded1-ref and normal endosperm and serves to identify direct target genes together with DAP-seq data.
Project description:The goals of this study are to study the regulatory network of the two maize endosperm-specific transcription factors O2 and PBF by 16-DAP endosperm transcriptome profiling (RNA-seq) of their mutants and wild type. The results utilize the expression pattern of global genes regulated by PBF and O2 to elucidate their control for storage compounds synthesis in maize kernels.
Project description:The goals of this study are to study the regulatory network of the two maize endosperm-specific transcription factors O2 and PBF by 16-DAP endosperm transcriptome profiling (RNA-seq) of their mutants and wild type. The results utilize the expression pattern of global genes regulated by PBF and O2 to elucidate their control for storage compounds synthesis in maize kernels. The 16-DAP endosperm transcriptome of wild type (WT) and mutants including opaque2, PbfRNAi and PbfRNAi;o2 were generated by RNA-seq with three biological replicates per genotype on Illumina HiSeqTM2500.
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:Transcription factors (TFs) play an important role in maize endosperm development regulation. The temporal RNA-seq and co-expression network analysis of maize endosperm reveals a hiararchical regulatory network architechture modulating the endosperm development. In the network, NKD1 and NKD2 are central regulators, and GBF1, HSFTF10, NACTF49 and HB115 are secondary regulators downstream of NKD1 and 2. To further test the relationship between these TFs, a DNA affinity purification and sequencing (DAP-seq) assay was performed. The result shows that the assay on NKD1 and NKD2 called 1,951 and 56,855 peaks, and 93 and 1,692 peaks are located within 3 kb distance to transcription starting site (TSS), respectively. And assays on GBF1, HSFTF10, NACTF49 and HB115 called 15,543; 38,147; 7,388 and 936 peaks, respectively.
Project description:The cereal endosperm consists of starchy endosperm (ST) cells, which accumulate storage proteins and starch, the peripheral aleurone (AL) cells, which mobilize these storage compounds during germination, and transfer cells in contact with the maternal vascular tissues, and the embryo-surrounding region. We conducted RNA-sequencing and analyzed transcript profiles of AL and ST tissues at 18 and 22 days after pollination (DAP), when storage compounds such as proteins, starch, triacylglycerols, specialized metabolites, and minerals are actively synthesized in the maize endosperm. We combined published RNA-seq datasets from other kernel tissues at different developmental stages to analyze gene expression connected to synthesis and accumulation of storage compounds and metabolites. Using weighted correlation network analysis (WGCNA), we identified gene modules associated with metabolic pathways related to nutritional properties of the maize endosperm. We also provide information of novel marker genes specifically expressed in AL and ST, at either early or late developmental stages. This study is important for understanding maize endosperm development and for developing strategies to improve nutritional quality of maize kernels.
2017-05-02 | GSE95678 | GEO
Project description:Micro-endosperm high oil maize RNA-seq