Project description:Plant genomes have undergone multiple rounds of whole genome duplication and polyploidy over time. As a result, many plant species, including Arabidopsis thaliana, have numerous retained duplicate blocks or syntenic regions within their genomes, resulting in the retention of paralogous genes. We deleted four large duplicated blocks, ranging from ~115 kb to ~684 kb using Staphylococcus aureus Cas9 (SaCas9) to explore the effects of knocking out these retained blocks in Arabidopsis. Deletions were subsequently verified using whole genome sequencing, which revealed that there were limited off-target effects. The number of deleted genes ranged from 16 to 60, and deleted transposable element (TE) genes ranged from 4 to 112 among the four deleted retained blocks. Two deletion lines showed distinct phenotypes resulting from the loss of many genes, while two other deletions displayed no obvious defects for flowering time or hypocotyl elongation. Moreover, RNA sequencing (RNA-seq) analysis of the deleted lines revealed that expression compensation was not a general response to the deleted regions. Thus, it is possible to obtain viable plants when deleting large genomic regions that may be redundant or regions that contain non-essential genes. These results demonstrate that large chromosomal deletions can be used as a tool for various genome engineering approaches, such as genome minimization in plants and allele replacement using homology-directed repair mechanisms and other precision editing methods. Targeted deletions of large chromosome fragments will be a valuable tool for research and biotechnology applications.
Project description:m6A profiling in two accessions of Arabidopsis thaliana (Can-0 and Hen-16) using the m6A-targeted antibody coupled with high-throughput sequencing m6A-seq in two accessions of Arabidopsis, two replicates for each sample
Project description:In chronic lymphocytic leukemia (CLL), 13q14 and 11q22-23 deletions are found in 2/3 of the cases. 11q22-23 deletions are associated with poor survival, whereas 13q14 deletions as single abnormality are often found in indolent disease forms. The molecular basis for this difference in prognosis is not known. ARHGAP20 encodes an evolutionarily conserved protein. In the zebra fish (Danio rerio) genome the syntenic regions of human chromosomal bands 13q14 and 11q22-23 are juxtaposed. The similar expression profiles of ARHGAP20 in 13q14 and 11q22-23 deleted CLL cases suggest a molecular connection and an intriguing mechanism of regulation.
Project description:We have implemented an integrated Systems Biology approach to analyze overall transcriptomic reprogramming and systems level defense responses in the model plant Arabidopsis thaliana during an insect (Brevicoryne brassicae) and a bacterial (Pseudomonas syringae pv. tomato strain DC3000) attack. The main aim of this study was to identify the attacker-specific and general defense response signatures in the model plant Arabidopsis thaliana while attacked by phloem feeding aphids or pathogenic bacteria. Defense responses and networks, unique and specific for aphid or Pseudomonas stresses were identified. Our analysis revealed a probable link between biotic stress and microRNAs in Arabidopsis and thus opened up a new direction to conduct large-scale targeted experiments to explore detailed regulatory links among them. The presented results provide a first comprehensive understanding of Arabidopsis - B. brassicae and Arabidopsis - P. syringae interactions at a systems biology level.
Project description:We have implemented an integrated Systems Biology approach to analyze overall transcriptomic reprogramming and systems level defense responses in the model plant Arabidopsis thaliana during an insect (Brevicoryne brassicae) and a bacterial (Pseudomonas syringae pv. tomato strain DC3000) attack. The main aim of this study was to identify the attacker-specific and general defense response signatures in the model plant Arabidopsis thaliana while attacked by phloem feeding aphids or pathogenic bacteria. Defense responses and networks, unique and specific for aphid or Pseudomonas stresses were identified. Our analysis revealed a probable link between biotic stress and microRNAs in Arabidopsis and thus opened up a new direction to conduct large-scale targeted experiments to explore detailed regulatory links among them. The presented results provide a first comprehensive understanding of Arabidopsis - B. brassicae and Arabidopsis - P. syringae interactions at a systems biology level.
Project description:Trimethylation of histone H3 lysine27 (H3K27me3) plays critical roles in regulating animal development, and in several cases, H3K27me3 is also required for the proper expression of developmentally important genes in plants. However, the extent to which H3K27me3 regulates plant genes on a genome-wide scale remains unknown. In addition, it is not clear whether the establishment and spreading of H3K27me3 occur through the same mechanisms in plants and animals. Here we identified regions containing H3K27me3 in the genome of the flowering plant Arabidopsis thaliana using a high-density whole-genome tiling microarray. The results suggest that H3K27me3 is a major silencing mechanism in plants that regulates an unexpectedly large number of genes in Arabidopsis (~4,400), and that the maintenance of H3K27me3 is largely independent of other epigenetic pathways such as DNA methylation or RNAi. Unlike in animals where H3K27m3 occupies large genomic regions, we found that H3K27m3 domains in Arabidopsis were largely restricted to the transcribed regions of single genes. Furthermore, unlike in animals systems, H3K27m3 domains were not preferentially associated with low nucleosome density regions. The results suggest that different mechanisms may underlie the establishment and spreading of H3K27me3 in plants and animals. Keywords: genomic
Project description:Trimethylation of histone H3 lysine27 (H3K27me3) plays critical roles in regulating animal development, and in several cases, H3K27me3 is also required for the proper expression of developmentally important genes in plants. However, the extent to which H3K27me3 regulates plant genes on a genome-wide scale remains unknown. In addition, it is not clear whether the establishment and spreading of H3K27me3 occur through the same mechanisms in plants and animals. Here we identified regions containing H3K27me3 in the genome of the flowering plant Arabidopsis thaliana using a high-density whole-genome tiling microarray. The results suggest that H3K27me3 is a major silencing mechanism in plants that regulates an unexpectedly large number of genes in Arabidopsis (~4,400), and that the maintenance of H3K27me3 is largely independent of other epigenetic pathways such as DNA methylation or RNAi. Unlike in animals where H3K27m3 occupies large genomic regions, we found that H3K27m3 domains in Arabidopsis were largely restricted to the transcribed regions of single genes. Furthermore, unlike in animals systems, H3K27m3 domains were not preferentially associated with low nucleosome density regions. The results suggest that different mechanisms may underlie the establishment and spreading of H3K27me3 in plants and animals. Keywords: ChIP-chip
Project description:Trimethylation of histone H3 lysine27 (H3K27me3) plays critical roles in regulating animal development, and in several cases, H3K27me3 is also required for the proper expression of developmentally important genes in plants. However, the extent to which H3K27me3 regulates plant genes on a genome-wide scale remains unknown. In addition, it is not clear whether the establishment and spreading of H3K27me3 occur through the same mechanisms in plants and animals. Here we identified regions containing H3K27me3 in the genome of the flowering plant Arabidopsis thaliana using a high-density whole-genome tiling microarray. The results suggest that H3K27me3 is a major silencing mechanism in plants that regulates an unexpectedly large number of genes in Arabidopsis (~4,400), and that the maintenance of H3K27me3 is largely independent of other epigenetic pathways such as DNA methylation or RNAi. Unlike in animals where H3K27m3 occupies large genomic regions, we found that H3K27m3 domains in Arabidopsis were largely restricted to the transcribed regions of single genes. Furthermore, unlike in animals systems, H3K27m3 domains were not preferentially associated with low nucleosome density regions. The results suggest that different mechanisms may underlie the establishment and spreading of H3K27me3 in plants and animals. Keywords: ChIP-chip