Project description:This study used the mutants nrpe1-11 and ros1-4 to assess the impact of RNA-directed DNA methylation (RdDM) and ROS1 on the Arabidopsis thaliana (ecotype Col-0) methylome.
Project description:Whole genome shotgun bisulfite sequencing, small RNA sequencing and transcriptome sequencing of wildtype Arabidopsis plants (Col-0), and met1, drm1 drm2 cmt3, and ros1 dml2 dml3 null mutants using the Illumina Genetic Analyzer. A comparison was performed with regions of the genome containing cytosine DNA methylation identified by methylcytosine immunoprecipitation and whole-genome oligonucleotide tiling microarrays, for wildtype Col-0. Understanding the epigenetic regulatory mechanisms that mediate control of transcription at multiple levels is critical to understanding how plants develop and respond to their environment. We combined next-generation sequencing by synthesis (SBS) technology with novel methods for direct sequencing of the entire cytosine methylome (methylC-seq), transcriptome (RNA-seq), and the small RNA component of the transcriptome (smRNA-seq) to create a set of highly integrated epigenome maps for Arabidopsis thaliana, in conjunction with a set of informative mutants defective in DNA methyltransferase and DNA demethylase activity. At single-base resolution we discovered extensive, previously undetected, DNA methylation, identified the context and level of methylation at each site, and found that local composition has effects upon DNA methylation state. Deep sequencing of the smRNAome exposed a direct relationship between the location and abundance of smRNAs and DNA methylation, perturbation of smRNA biogenesis upon loss of CpG DNA methylation, and a tendency for smRNAs to direct strand-specific DNA methylation in the region of RNA-DNA homology. Finally, strand-specific RNA-seq revealed changes in the transcript abundance of hundreds of genes upon alteration of the DNA methylation state, and enabled the identification of numerous previously unidentified genes regulated by DNA methylation. Keywords: Whole genome shotgun bisulfite sequencing, small RNA sequencing, transcriptome sequencing, methylcytosine immunoprecipitation, whole-genome oligonucleotide tiling microarrays Whole genome shotgun bisulfite sequencing, small RNA sequencing and transcriptome sequencing of wildtype Arabidopsis plants (Col-0), and met1, drm1 drm2 cmt3, and ros1 dml2 dml3 null mutants using the Illumina Genetic Analyzer. A comparison was performed with regions of the genome containing cytosine DNA methylation identified by methylcytosine immunoprecipitation and whole-genome oligonucleotide tiling microarrays, for wildtype Col-0.
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:The aim of this study was to analyze the impact of autotetraploidy on gene expression in Arabidopsis thaliana by comparing diploid versus tetraploid transcriptomes. In particular, this included the comparison of the transcriptome of different tetraploid A. thaliana ecotypes (Col-0 vs. Ler-0). The study was extended to address further aspects. One was the comparison of the transcriptomes in subsequent generations. This intended to obtain information on the genome wide stability of autotetraploid gene expression. Another line of work compared the transcriptomes of different diploid vs. tetraploid tissues. This aimed to investigate whether particular gene groups are specifically affected during the development of A. thaliana autotetraploids. Samples 1-8: Arabidopsis thaliana Col-0 tetraploid transcriptome. Transcriptional profiling and comparison of diploid vs. tetraploid Col-0 seedlings. The experiment was carried out with pedigree of independently generated and assessed tetraploid Col-0 lines. Samples 9-12: Arabidopsis thaliana Ler-0 tetraploid transcriptome. Transcriptional profiling and comparison of diploid vs. tetraploid Ler-0 seedlings. The experiment was carried out with pedigree of independently generated and assessed tetraploid Ler-0 lines. Samples 13-24: Arabidopsis thaliana Col-0 tetraploid transcriptome. Transcriptional profiling and comparison of diploid vs. tetraploid Col-0 leaves (6th - 8th). The experiment was carried out with pedigree of independently generated and assessed tetraploid Col-0 lines. Samples 25-32: Arabidopsis thaliana Ler-0 tetraploid transcriptome. Transcriptional profiling and comparison of diploid vs. tetraploid Ler-0 leaves (6th - 8th). The experiment was carried out with pedigree of independently generated and assessed tetraploid Ler-0 lines. Samples 33-36: Arabidopsis thaliana Ler-0 tetraploid transcriptome. Transcriptional profiling and comparison of tetraploid vs. tetraploid Ler-0 seedlings from the second (F2) and third (F3) generation after induction, respectively. The experiment was carried out with pedigree of independently generated and assessed tetraploid Ler-0 lines. Samples 37-40: Arabidopsis thaliana Col-0 tetraploid transcriptome. Transcriptional profiling and comparison of tetraploid vs. tetraploid Col-0 seedlings from the second (F2) and third (F3) generation after induction, respectively. The experiment was carried out with pedigree of independently generated and assessed tetraploid Col-0 lines. Samples 41-44: Arabidopsis thaliana Col-0/Ler-0 diploid transcriptome. Transcriptional profiling and comparison of diploid Col-0 vs. diploid Ler-0 seedlings. The experiment was carried out with pedigree of esrablished lines. Samples 45-48: Arabidopsis thaliana Col-0/Ler-0 tetraploid transcriptome. Transcriptional profiling and comparison of tetraploid Col-0 vs tetraploid Ler-0 seedlings. The experiment was carried out with pedigree of independently generated and assessed tetraploid Col-0 and Ler-0 lines.
Project description:We analysed transcriptome changes in Arabidopsis Col-0 and ros1-4 mutant seeds (3 stages corresponding mature (mat), germination II (II) and germination IV (IV)
Project description:Using MethylC-Seq to provide single-base resolution of DNA methylation status in ros1-13 mutant Whole genome methylation maps of ros1-13 (with 35S-SUC2 transgene) was generated using BS-seq
Project description:This set consists of small RNAs sequenced from two replicates of wildtype and two replicates of RDR6-15 knockout Arabidopsis thaliana Col-0 leaf samples. RDR6 is required for the production of tasRNAs (trans-acting small RNAS) and so tags associated with the tasRNA loci should be severely down-regulated or absent in the knockout compared to wildtype. The set can thus be used as containing known true positives for testing differential expression detection methods.