Project description:We analysed the effect of the deficiency Df(2R)ED3921 and Df(2R)ED50000 on gene expression in embryos (stage 0-11), and wing imaginal discs and brains from 3rd instar larvae. Df(2R)ED3921 and Df(2R)ED50000 were described in Ragab et al. (2005) Genetics 172:1069-1078 2005.
Project description:DNA methylation and histone H3 lysine 9 dimethylation (H3K9me2) are important epigenetic repression marks for silencing transposons in heterochromatin and regulating gene expression in plant development. However, the mechanistic relationship to other repressive marks, such as histone H3 lysine 27 trimethylation (H3K27me3), is unclear. OsFIE1 (Fertilization Independent Endosperm 1) encodes an Esc-like core component of the Polycomb repressive complex 2 (PRC2), which is involved in H3K27me3-mediated gene repression. Here, we identify a gain-of-function epi-allele (Epi-df) of rice OsFIE1; this allele exhibits a dwarf stature and various floral defects that are inherited in a dominant fashion. We found that Epi-df has no changes in its nucleotide sequence, but is hypo-methylated in the promoter and the 5' region of OsFIE1 and has reduced H3K9me2 and increased H3K4me3. In Epi-df, OsFIE1 was ectopically expressed and its imprinting status was disrupted. OsFIE1 interacted with rice E(z) homologs, consistent with its role in H3K27me3 repression. Ectopic expression of OsFIE1 in Epi-df resulted in alteration of H3K27me3 levels in hundreds of genes. Therefore, this work identifies a novel epi-allele involved in H3K27me3-mediated gene repression, that itself is highly regulated by histone H3K9me2, thereby shedding light on the link between two important epigenetic marks regulating rice development. We report the application of ChIP-Seq technology for high-throughput profiling of histone modifications in WT (wild type) and Epi-df (mutant). We demonstrate that the H3K27me3 status is perturbed at target genes and leads to mis-regulated expression in Epi-df.
Project description:DNA methylation and histone H3 lysine 9 dimethylation (H3K9me2) are important epigenetic repression marks for silencing transposons in heterochromatin and regulating gene expression in plant development. However, the mechanistic relationship to other repressive marks, such as histone H3 lysine 27 trimethylation (H3K27me3), is unclear. OsFIE1 (Fertilization Independent Endosperm 1) encodes an Esc-like core component of the Polycomb repressive complex 2 (PRC2), which is involved in H3K27me3-mediated gene repression. Here, we identify a gain-of-function epi-allele (Epi-df) of rice OsFIE1; this allele exhibits a dwarf stature and various floral defects that are inherited in a dominant fashion. We found that Epi-df has no changes in its nucleotide sequence, but is hypo-methylated in the promoter and the 5' region of OsFIE1 and has reduced H3K9me2 and increased H3K4me3. In Epi-df, OsFIE1 was ectopically expressed and its imprinting status was disrupted. OsFIE1 interacted with rice E(z) homologs, consistent with its role in H3K27me3 repression. Ectopic expression of OsFIE1 in Epi-df resulted in alteration of H3K27me3 levels in hundreds of genes. Therefore, this work identifies a novel epi-allele involved in H3K27me3-mediated gene repression, that itself is highly regulated by histone H3K9me2, thereby shedding light on the link between two important epigenetic marks regulating rice development.
Project description:We analysed the effect of the deficiency Df(2R)ED3921 and Df(2R)ED50000 on gene expression in embryos (stage 0-11), and wing imaginal discs and brains from 3rd instar larvae. Df(2R)ED3921 and Df(2R)ED50000 were described in Ragab et al. (2005) Genetics 172:1069-1078 2005. RNA from Df(2R)ED3921 and Df(2R)ED50000 embryos was compared to a pool of RNA extracted from wild-type embryos at the same stage. For each genotype, 4 independent biological replicates were performed (2 of these dyes swapped with respect to the other two). The same experimental protocol and genotypes were used for the analysis in dissected wing imaginal discs and brains from 3rd instar larvae.
Project description:We identified and characterized a rice epigenetic mutant Epi-df which exhibits a dwarf stature and various floral defects that are inherited in a dominant fashion. We demonstrated that Epi-df participates in Polycomb repressive complex 2 (PRC2) mediated gene silencing. Epigenetic mutations results in ectopic expression of Epi-df and pleiotropic developmental defects in mutant plants. Moreover, ectopic expression of Epi-df leads to mis-regulated H3K27me3 and changed expression of hundreds of genes involved in a wide range of biological processes. We used microarrays to identify differentially expressed genes in Epi-df.
Project description:Transcriptional profiling of chicken embryo fibroblast (CEF) cells comparing CEF derived immortal chicken embryo fibroblast cell line (DF-1). Goal was to determine differentially expressed genes of CEF which were changed responding DF-1.