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: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. For genome-wide expression analysis of Epi-df, three replicates of WT and Epi-df samples (RNA from 3-week-old seedlings) were analyzed on Affymetrix Genechip® Rice Genome arrays by an Affymetrix service facility (CapitalBio Corporation) according to the manufacturer’s protocols. Genes showing a 2-fold change with a q-value ≤ 0.05 were considered to be differentially expressed.
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:To reveal the underlying molecular mechanism of jasmonate inhibits gibberellins signaling in rice, we performed transcriptional profiling of wild type nipponbare and mutant coi1-13 plants on a global scale using the Affymetrix GeneChip Rice Genome Array
Project description:To reveal the underlying molecular mechanism of Gif1 action in the control of grain filling and yield improvement, we performed transcriptional profiling of wild type Zhonghua11 and mutant gif1 plants in early filling stage on a global scale using the Affymetrix GeneChip Rice Genome Array Keywords: Filling stage
Project description:The goal of this work is to identify the gene regulatory hubs that control nitrogen-use in Oryza sativa, one of the most important crop plants, by using a combination of genomics, bioinformatics and systems biology approaches. Here, we evaluate the role of bZIP1, a transcription factor involved in light and nitrogen sensing, by exposing wild-type (WT) and bZIP1 T-DNA null mutant plants to a combinatorial space of N and L treatment conditions. We use ANOVA analysis combined with clustering and Boolean modeling, to evaluate the role of bZIP1 in mediating L and N signaling genome-wide. We also study the interspecies conservation, comparing rice with Arabidopsis thaliana nitrogen transcriptomes, to help identify conserved nitrogen regulation.