Project description:Using MethylC-Seq to provide single-base resolution of DNA methylation status in WT, nrpd1-3, nrpe1-11, ros1-4 single mutants and ros1-4nrpd1-3 double mutant
Project description:Arabidopsis ROS1 is the first genetically characterized DNA demethylase in eukaryotes. Dysfunction of ROS1 leads to increase in DNA methylation level at thousands of genomic loci. However, the features of ROS1 targets are not well understood. In this study, we identified and characterized ROS1 target loci in Arabidopsis Col-0 and C24 ecotypes. Most ROS1 targets are transposable elements (TEs) and intergenic regions. Compared to other TEs, ROS1-targeted TEs are closer to protein coding genes, suggesting a role for ROS1 in preventing the spreading of DNA methylation from highly methylated TEs to nearby genes. Interestingly, we found that unlike general TEs, ROS1 targets are associated with an enrichment of H3K18ac and H3K27me3, and depletion of H3K27me and H3K9me2. We investigated the antagonism between ROS1 and RNA-directed DNA methylation (RdDM) by identifying and characterizing thousands of genomic regions regulated by both ROS1 and RdDM. Unexpectedly, we uncovered thousands of previously unidentified RdDM targets by analyzing the DNA methylome of ros1/nrpd1 double mutant plants. In addition, we show that ROS1 also antagonizes RdDM-independent DNA methylation at more than a thousand genomic loci. Our results provide significant insights into the genome-wide effects of both ROS1-mediated active DNA demethylation and RNA-directed DNA methylation as well as their interaction in plants. Using small RNA-Seq(sRNA-Seq) to get small RNA profiling of WT, ros1-4, nrpd1 single mutants and ros1-4/nrpd1doubble mutant
Project description:Investigation of whole genome gene expression level changes in several Arabidopsis thaliana mutants (nrpd1, nrpe1, ros1 dml2 dml3) compared to wild-type Col-0. The mutants analyzed in this study are further described in Le et al. 'DNA demethylases target promoter transposable elements to positively regulate stress responsive genes in Arabidopsis' . Genome Biology (in press).
Project description:Investigation of whole genome gene expression level changes in several Arabidopsis thaliana mutants (nrpd1, nrpe1, ros1 dml2 dml3) compared to wild-type Col-0. The mutants analyzed in this study are further described in Le et al. 'DNA demethylases target promoter transposable elements to positively regulate stress responsive genes in Arabidopsis' . Genome Biology (in press). A twelve chip study using total RNA recovered from three week-old plants grown on Murashige Skoog sucrose agar. The number of biological replicates for each plant genotype were as follows: Col-0 (3 biological replicates), rdd (2), nrpd1 (2) and nrpe1 (2) respectively. Each array contains 60-mer probes targeting 39,042 genes (TAIR 9.0) with 4 probes per gene.
Project description:Using BS-Seq to provide single-base resolution of DNA methylation status in 35S-SUC2 WT and antisilencing mutants (arp6, pie1, h2a.z, idm1, and ros1)
