Similar Datasets
Project description:We present and propose the application of 5-Ethynyl uridine for metabolic labeling of RNAs in plants, which allows the isolation of neo-synthesized RNAs from intact plants. This system provides the possibility to investigate neo-synthesized RNAs from living plant cells. Neu-RNAseq can be applied for the detection of splicing variants, especially RNAs containing retained introns and alternative 5’ and 3’ splice sites. A subset of unspliced RNAs identified by Neu-Seq is subjected for elimination by the NMD pathway, but the majority of the RNA splicing variants detected in Neu-Seq libraries will be further processed into mature mRNAs.
2018-10-31 | GSE118458 | GEO
Project description:We provide evidence that 5-EU metabolic labeling of Arabidopsis RNAs can be used for pulse-chase experiments, which allowed us to determine Arabidopsis RNA half-lives genome-wide without chemical inhibition of transcription. Similar to BRIC-Seq, we performed 5-EU IP chase (ERIC)-Seq in seedlings of A. thaliana. Hierarchical clustering of gene expression values allowed us to define at least five clusters of mRNAs that exhibited distinct degradation kinetics. To determine the RNA half-lives of each group, we applied an exponential decay model and a locally weighted scatterplot smoothing (LOWESS) and calculated the time where the concentration was halved. It became obvious that the half-lives determined by ERIC-Seq are much shorter than the ones determined after treatment with cordycepin or actinomycin D, respectively. We found that genes belonging to cluster A exhibiting the shortest half-lives are enriched in genes transcribed into non-coding RNAs, stress-related genes, genes involved in hormonal pathways and the metabolism of polyamines, which are also involved in stress responses. On the contrary, genes from cluster E, which have the longest half-lives, are specifically enriched in genes responsible for mitochondrial and plastic functions as well as primary metabolism (such as the TCA cycle)
2018-10-31 | GSE118461 | GEO
Project description:Metabolic labeling of RNAs uncovers hidden features and dynamics of the Arabidopsis thaliana transcriptome
| PRJNA485744 | ENA
Project description:Metabolic labeling of RNAs uncovers hidden features and dynamics of the Arabidopsis thaliana transcriptome [ERIC]
| PRJNA485747 | ENA
Project description:Metabolic labeling of RNAs uncovers hidden features and dynamics of the Arabidopsis thaliana transcriptome [NEU]
| PRJNA485748 | ENA
Project description:Hints from animals point to the existence of two novel small RNA (sRNA) species surrounding the transcription start sites (TSSs) and the termini of the genes, respectively. In this study, we performed a comprehensive search for the two sRNA species named promoter-associated sRNAs (PASRs) and terminus-associated sRNAs (TASRs) in Arabidopsis. By using sRNA sequencing data from wild type plants and several mutants related to the sRNA biogenesis, Argonaute (AGO) 1- and AGO4-associated sRNA sequencing data, double-stranded RNA sequencing (dsRNA-seq) data, and DNA methylation profiling data, the biogenesis and action pathways of the PASRs and the TASRs were investigated. PASR and TASR peaks were identified on hundreds of the protein-coding genes. Deep analysis uncovered that some of the sRNA peaks were covered by dsRNA-seq reads, and these peaks were significantly repressed in specific mutants. Besides, certain PASRs and TASRs were preferentially recruited by AGO4, and site-specific DNA methylation signals encompassing the genomic loci of these sRNAs were also detected. Accordingly, we proposed a model that certain PASRs and TASRs were generated through a specific Pol IV-, RDR-, DCL-dependent pathway, and they were associated with AGO4 to perform site-specific DNA methylation on their host genes. The above results indicate the existence of PASRs and TASRs in plants. The proposed biogenesis pathway and action mode of the PASRs and TASRs could facilitate us to perform in-depth functional studies on these novel sRNA species.
| S-EPMC5207706 | biostudies-literature
Project description:Cellular RNA levels are determined by the interplay of RNA production, processing and degradation. However, because most studies of RNA regulation do not distinguish the separate contributions of these processes, little is known about how they are temporally integrated. Here we combine metabolic labeling of RNA at high temporal resolution with advanced RNA quantification and computational modeling to estimate RNA transcription and degradation rates during the response of mouse dendritic cells to lipopolysaccharide. We find that changes in transcription rates determine the majority of temporal changes in RNA levels, but that changes in degradation rates are important for shaping sharp 'peaked' responses. We used sequencing of the newly transcribed RNA population to estimate temporally constant RNA processing and degradation rates genome wide. Degradation rates vary significantly between genes and contribute to the observed differences in the dynamic response. Certain transcripts, including those encoding cytokines and transcription factors, mature faster. Our study provides a quantitative approach to study the integrative process of RNA regulation.
| S-EPMC3114636 | biostudies-literature
Project description:Telomere function is influenced by chromatin structure and organization, which usually involves epigenetic modifications. We describe here the chromatin structure of Arabidopsis thaliana telomeres. Based on the study of six different epigenetic marks we show that Arabidopsis telomeres exhibit euchromatic features. In contrast, subtelomeric regions and telomeric sequences present at interstitial chromosomal loci are heterochromatic. Histone methyltransferases and the chromatin remodeling protein DDM1 control subtelomeric heterochromatin formation. Whereas histone methyltransferases are required for histone H3K9(2Me) and non-CpG DNA methylation, DDM1 directs CpG methylation but not H3K9(2Me) or non-CpG methylation. These results argue that both kinds of proteins participate in different pathways to reinforce subtelomeric heterochromatin formation.
| S-EPMC3064777 | biostudies-literature
Project description:BACKGROUND: Oomycetes are a group of filamentous microorganisms that includes both animal and plant pathogens and causes major agricultural losses. Phytophthora species can infect most crops and plants from natural ecosystems. Despite their tremendous economic and ecologic importance, few effective methods exist for limiting the damage caused by these species. New solutions are required, and their development will require improvements in our understanding of the molecular events governing infection by these pathogens. In this study, we characterized the genetic program activated during penetration of the plant by the soil-borne pathogen Phytophthora parasitica. RESULTS: Using all the P. parasitica sequences available in public databases, we generated a custom oligo-array and performed a transcriptomic analysis of the early events of Arabidopsis thaliana infection. We characterized biological stages, ranging from the appressorium-mediated penetration of the pathogen into the roots to the occurrence of first dead cells in the plant. We identified a series of sequences that were transiently modulated during host penetration. Surprisingly, we observed an overall down regulation of genes encoding proteins involved in lipid and sugar metabolism, and an upregulation of functions controlling the transport of amino acids. We also showed that different groups of genes were expressed by P. parasitica during host penetration and the subsequent necrotrophic phase. Differential expression patterns were particularly marked for cell wall-degrading enzymes and other proteins involved in pathogenicity, including RXLR effectors. By transforming P. parasitica with a transcriptional fusion with GFP, we showed that an RXLR-ecoding gene was expressed in the appressorium and infectious hyphae during infection of the first plant cell. CONCLUSION: We have characterized the genetic program activated during the initial invasion of plant cells by P. parasitica. We showed that a specific set of proteins, including effectors, was mobilized for penetration and to facilitate infection. Our detection of the expression of an RXLR encoding gene by the appressorium and infection hyphae highlights a role of this structure in the manipulation of the host cells.
| S-EPMC4111850 | biostudies-literature
Project description:The nucleus is a definitive feature of eukaryotic cells, comprising twin bilamellar membranes, the inner and outer nuclear membranes, which separate the nucleoplasmic and cytoplasmic compartments. Nuclear pores, complex macromolecular assemblies that connect the two membranes, mediate communication between these compartments. To explore the morphology, topology, and dynamics of nuclei within living plant cells, we have developed a novel method of confocal laser scanning fluorescence microscopy under time-lapse conditions. This is used for the examination of the transgenic expression in Arabidopsis thaliana of a chimeric protein, comprising the GFP (Green-Fluorescent Protein of Aequorea victoria) translationally fused to an effective nuclear localization signal (NLS) and to beta-glucuronidase (GUS) from E. coli. This large protein is targeted to the nucleus and accumulates exclusively within the nucleoplasm. This article provides online access to movies that illustrate the remarkable and unusual properties displayed by the nuclei, including polymorphic shape changes and rapid, long-distance, intracellular movement. Movement is mediated by actin but not by tubulin; it therefore appears distinct from mechanisms of nuclear positioning and migration that have been reported for eukaryotes. The GFP-based assay is simple and of general applicability. It will be interesting to establish whether the novel type of dynamic behavior reported here, for higher plants, is observed in other eukaryotic organisms.
| S-EPMC14952 | biostudies-literature