Arabidopsis thaliana
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ABSTRACT:
OTHER RELATED OMICS DATASETS IN: GSE5254
PROVIDER: PRJNA87483 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Plants use light as a source of energy for photosynthesis and as a source of environmental information perceived by photoreceptors. Testing whether plants can complete their cycle if light provides energy but no information about the environment requires a plant devoid of phytochromes because all photosynthetically active wavelengths activate phytochromes. Producing such a quintuple mutant of Arabidopsis thaliana has been challenging, but we were able to obtain it in the flowering locus T (ft) mutant background. The quintuple phytochrome mutant does not germinate in the FT background, but it germinates to some extent in the ft background. If germination problems are bypassed by the addition of gibberellins, the seedlings of the quintuple phytochrome mutant exposed to red light produce chlorophyll, indicating that phytochromes are not the sole red-light photoreceptors, but they become developmentally arrested shortly after the cotyledon stage. Blue light bypasses this blockage, rejecting the long-standing idea that the blue-light receptors cryptochromes cannot operate without phytochromes. After growth under white light, returning the quintuple phytochrome mutant to red light resulted in rapid senescence of already expanded leaves and severely impaired expansion of new leaves. We conclude that Arabidopsis development is stalled at several points in the presence of light suitable for photosynthesis but providing no photomorphogenic signal.
| S-EPMC2842051 | 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
Project description:Higher plants produce four classes of tetrapyrroles, namely, chlorophyll (Chl), heme, siroheme, and phytochromobilin. In plants, tetrapyrroles play essential roles in a wide range of biological activities including photosynthesis, respiration and the assimilation of nitrogen/sulfur. All four classes of tetrapyrroles are derived from a common biosynthetic pathway that resides in the plastid. In this article, we present an overview of tetrapyrrole metabolism in Arabidopsis and other higher plants, and we describe all identified enzymatic steps involved in this metabolism. We also summarize recent findings on Chl biosynthesis and Chl breakdown. Recent advances in this field, in particular those on the genetic and biochemical analyses of novel enzymes, prompted us to redraw the tetrapyrrole metabolic pathways. In addition, we also summarize our current understanding on the regulatory mechanisms governing tetrapyrrole metabolism. The interactions of tetrapyrrole biosynthesis and other cellular processes including the plastid-to-nucleus signal transduction are discussed.
| S-EPMC3268503 | biostudies-literature
Project description:BACKGROUND:Long non-coding RNAs (lncRNAs) have emerged as new class of regulatory molecules in animals where they regulate gene expression at transcriptional and post-transcriptional level. Recent studies also identified lncRNAs in plant genomes, revealing a new level of transcriptional complexity in plants. Thousands of lncRNAs have been predicted in the Arabidopsis thaliana genome, but only a few have been studied in depth. RESULTS:Here we report the identification of Arabidopsis lncRNAs that are expressed during the vegetative stage of development in either the shoot apical meristem or in leaves. We found that hundreds of lncRNAs are expressed in these tissues, of which 50 show differential expression upon an increase in ambient temperature. One of these lncRNAs, FLINC, is down-regulated at higher ambient temperature and affects ambient temperature-mediated flowering in Arabidopsis. CONCLUSION:A number of ambient temperature responsive lncRNAs were identified with potential roles in the regulation of temperature-dependent developmental changes, such as the transition from the vegetative to the reproductive (flowering) phase. The challenge for the future is to characterize the biological function and molecular mode of action of the large number of ambient temperature-regulated lncRNAs that have been identified in this study.
| S-EPMC6045843 | biostudies-literature
Project description:Although plant development is highly reproducible, some stochasticity exists. This developmental stochasticity may be caused by noisy gene expression. Here we analyze the fluctuation of protein expression in Arabidopsis thaliana. Using the photoconvertible KikGR marker, we show that the protein expressions of individual cells fluctuate over time. A dual reporter system was used to study extrinsic and intrinsic noise of marker gene expression. We report that extrinsic noise is higher than intrinsic noise and that extrinsic noise in stomata is clearly lower in comparison to several other tissues/cell types. Finally, we show that cells are coupled with respect to stochastic protein expression in young leaves, hypocotyls and roots but not in mature leaves. Our data indicate that stochasticity of gene expression can vary between tissues/cell types and that it can be coupled in a non-cell-autonomous manner.
| S-EPMC5730595 | 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:Cytosine methylation of repetitive sequences is widespread in plant genomes, occurring in both symmetric (CpG and CpNpG) as well as asymmetric sequence contexts. We used the methylation-dependent restriction enzyme McrBC to profile methylated DNA using tiling microarrays of Arabidopsis Chromosome 4 in two distinct ecotypes, Columbia and Landsberg erecta. We also used comparative genome hybridization to profile copy number polymorphisms. Repeated sequences and transposable elements (TEs), especially long terminal repeat retrotransposons, are densely methylated, but one third of genes also have low but detectable methylation in their transcribed regions. While TEs are almost always methylated, genic methylation is highly polymorphic, with half of all methylated genes being methylated in only one of the two ecotypes. A survey of loci in 96 Arabidopsis accessions revealed a similar degree of methylation polymorphism. Within-gene methylation is heritable, but is lost at a high frequency in segregating F(2) families. Promoter methylation is rare, and gene expression is not generally affected by differences in DNA methylation. Small interfering RNA are preferentially associated with methylated TEs, but not with methylated genes, indicating that most genic methylation is not guided by small interfering RNA. This may account for the instability of gene methylation, if occasional failure of maintenance methylation cannot be restored by other means.
| S-EPMC1892575 | biostudies-literature
Project description:In the post-genomic era much effort has been put on the discovery of gene function using functional genomics. Despite the advances achieved by these technologies in the understanding of gene function at the genomic and proteomic level, there is still a big genotype-phenotype gap. Metabolic profiling has been used to analyze organisms that have already been characterized genetically. However, there is a small number of studies comparing the metabolic profile of different tissues of distinct accessions. Here, we report the detection of over 14,000 and 17,000 features in inflorescences and leaves, respectively, in two widely used Arabidopsis thaliana accessions. A predictive Random Forest Model was developed, which was able to reliably classify tissue type and accession of samples based on LC-MS profile. Thereby we demonstrate that the morphological differences among A. thaliana accessions are reflected also as distinct metabolic phenotypes within leaves and inflorescences.
| S-EPMC4444734 | biostudies-literature
Project description:Terpenes constitute the largest class of plant secondary (or specialized) metabolites, which are compounds of ecological function in plant defense or the attraction of beneficial organisms. Using biochemical and genetic approaches, nearly all Arabidopsis thaliana (Arabidopsis) enzymes of the core biosynthetic pathways producing the 5-carbon building blocks of terpenes have been characterized and closer insight has been gained into the transcriptional and posttranscriptional/translational mechanisms regulating these pathways. The biochemical function of most prenyltransferases, the downstream enzymes that condense the C(5)-precursors into central 10-, 15-, and 20-carbon prenyldiphosphate intermediates, has been described, although the function of several isoforms of C(20)-prenyltranferases is not well understood. Prenyl diphosphates are converted to a variety of C(10)-, C(15)-, and C(20)-terpene products by enzymes of the terpene synthase (TPS) family. Genomic organization of the 32 Arabidopsis TPS genes indicates a species-specific divergence of terpene synthases with tissue- and cell-type specific expression profiles that may have emerged under selection pressures by different organisms. Pseudogenization, differential expression, and subcellular segregation of TPS genes and enzymes contribute to the natural variation of terpene biosynthesis among Arabidopsis accessions (ecotypes) and species. Arabidopsis will remain an important model to investigate the metabolic organization and molecular regulatory networks of terpene specialized metabolism in relation to the biological activities of terpenes.
| S-EPMC3268506 | biostudies-literature
Project description:The epigenetic features of defined chromosomal domains condition their biochemical and functional properties. Therefore, there is considerable interest in studying the epigenetic marks present at relevant chromosomal loci. Telomeric regions, which include telomeres and subtelomeres, have been traditionally considered heterochromatic. However, whereas the heterochromatic nature of subtelomeres has been widely accepted, the epigenetic status of telomeres remains controversial. Here, we studied the epigenetic features of Arabidopsis (Arabidopsis thaliana) telomeres by analyzing multiple genome-wide ChIP-seq experiments. Our analyses revealed that Arabidopsis telomeres are not significantly enriched either in euchromatic marks like H3K4me2, H3K9ac, and H3K27me3 or in heterochromatic marks such as H3K27me1 and H3K9me2. Thus, telomeric regions in Arabidopsis have a bimodal chromatin organization with telomeres lacking significant levels of canonical euchromatic and heterochromatic marks followed by heterochromatic subtelomeres. Since heterochromatin is known to influence telomere function, the heterochromatic modifications present at Arabidopsis subtelomeres could play a relevant role in telomere biology.
| S-EPMC9806604 | biostudies-literature