Covariations in the nuclear chloroplast transcriptome reveal a regulatory master-switch.
Ontology highlight
ABSTRACT:
SUBMITTER: Richly E
PROVIDER: S-EPMC1319183 | biostudies-literature | 2003 May
REPOSITORIES: biostudies-literature
Publications
Covariations in the nuclear chloroplast transcriptome reveal a regulatory master-switch.
Richly Erik E Dietzmann Angela A Biehl Alexander A Kurth Joachim J Laloi Christophe C Apel Klaus K Salamini Francesco F Leister Dario D
EMBO reports 20030501 5
The evolution of the endosymbiotic progenitor into the chloroplast organelle was associated with the transfer of numerous chloroplast genes into the nucleus. Hence, inter-organellar signalling, and the co-ordinated expression of sets of nuclear genes, was set up to control the metabolic and developmental status of the chloroplast. Here, we show by the differential-expression analysis of 3,292 genes, that most of the 35 environmental and genetic conditions tested, including plastid signalling mut ...[more]
Similar Datasets
Project description:Cell differentiation is associated with the functional differentiation of the nucleus, in which alteration of the expression profiles of transcription factors occurs to destine cell fate. Nuclear transport machineries, such as importin-α, have also been reported as critical factors that induce cell differentiation. Using various fluorescence live cell imaging methods, including time-lapse imaging, FRAP analysis and live-cell imaging associated correlative light and electron microscopy (Live CLEM) of Tetrahymena, a unicellular ciliated protozoan, we have recently discovered that type switching of the NPC is the earliest detectable event of nuclear differentiation. Our studies suggest that this type switching of the NPC directs the fate of the nucleus to differentiate into either a macronucleus or a micronucleus. Our findings in this organism may provide new insights into the role of the NPC in controlling nuclear functions in general in eukaryotes, including controlling cell fate leading to cell differentiation in multicellular metazoa.
| S-EPMC4594561 | biostudies-other
Project description:Alga-derived lipids represent an attractive potential source of biofuels. However, lipid accumulation in algae is a stress response tightly coupled to growth arrest, thereby imposing a major limitation on productivity. To identify master regulators of lipid accumulation and decipher the regulation of lipid biosynthetic pathway, we performed an integrative chromatin signature and transcriptomic analysis in the alga Chlamydomonas reinhardtii. Genome-wide histone modification profiling revealed remarkable differences in functional chromatin states between algae and higher eukaryotes and uncovered regulatory components at the core of lipid accumulation pathways. We identified the transcription factor PSR1 as a pivotal master switch that triggers cytosolic lipid hyper-accumulation an order of magnitude higher than stress regimens have achieved. Dissection of the PSR1 target network corroborates its central role in coordinating multiple stress responses. The comprehensive maps of functional chromatin signatures in a major clade of eukaryotic life and the discovery of a central regulator of algal lipid metabolism will facilitate targeted engineering strategies in microalgae. 1. Genome-wide H3K4me3 time series profiling (at 0 hr, 10 min, 30 min, 1 hr, 2hr, 6 hr, 8 hr, 24 hr and 48 hr after nitrogen starvation) was performed to determine time point to capture maximal chromatin changes. 2. Genome-wide H3K4me3, H3K27ac, H3K9me3, H3K27me3, H3K36me3 and Pol II profiling were performed at 0 hr, 1 hr after nitrogen starvation and 1 hr after sulfur starvation to determine chromatin signatures. Genome-wide H3K4me2 profiling was performed at 0 hr before starvation. 3. Transcriptome time series profiling (at 0 hr, 10 min, 30 min, 1 hr, 2hr, 6 hr, 8 hr, 24 hr and 48 hr after nitrogen and sulfur starvation separately) for chromatin signature characterization and integrative analysis. 4. Genome-wide PSR1 binding profiling was performed with polyclonal antibody against PSR1 peptide A region and PSR1 peptide B region individually. (At 30 min and 1 hr after nitrogen starvation, and 1 hr, 2 hr and 6 hr after sulfur starvation.) Please note that the following reference genome and gene models used in these experiments are linked below; C.reinhardtii_v5.3_genomic_scaffold_plastids.fasta.gz reference_gene_model.gtf.gz These are based off Phytozome (http://www.phytozome.net/) which does not provide access to earlier version data.
2015-07-28 | E-GEOD-59629 | biostudies-arrayexpress
Project description:Leukocyte migration is controlled by a leading-edge chemosensory pathway that generates the regulatory lipid phosphatidylinositol-3,4,5-trisphosphate (PIP3), a growth signal, thereby driving leading-edge expansion up attractant gradients toward sites of infection, inflammation, or tissue damage. PIP3 also serves as an important growth signal in growing cells and oncogenesis. The kinases PDK1, AKT1 or PKB, and PKCα are key components of a plasma-membrane-based PIP3 and Ca2+ signaling circuit that regulates these processes. PDK1 and AKT1 are recruited to the membrane by PIP3, whereas PKCα is recruited to the membrane by Ca2+. All three of these master kinases phosphoregulate an array of protein targets. For example, PDK1 activates AKT1, PKCα, and other AGC kinases by phosphorylation at key sites. PDK1 is believed to form PDK1-AKT1 and PDK1-PKCα heterodimers stabilized by a PDK1-interacting fragment (PIF) interaction between the PDK1 PIF pocket and the PIF motif of the AGC binding partner. Here, we present the first, to our knowledge, single-molecule studies of full-length PDK1 and AKT1 on target membrane surfaces, as well as their interaction with full-length PKCα. These studies directly detect membrane-bound PDK1-AKT1 and PDK1-PKCα heterodimers stabilized by PIF interactions formed at physiological ligand concentrations. PKCα exhibits eightfold higher PDK1 affinity than AKT1 and can competitively displace AKT1 from PDK1-AKT1 heterodimers. Ensemble activity measurements under matched conditions reveal that PDK1 activates AKT1 via a cis mechanism by phosphorylating an AKT1 molecule in the same PDK1-AKT1 heterodimer, whereas PKCα acts as a competitive inhibitor of this phosphoactivation reaction by displacing AKT1 from PDK1. Overall, the findings provide insights into the binding and regulatory interactions of the three master kinases on their target membrane and suggest that a recently described tumor suppressor activity of PKC isoforms may arise from its ability to downregulate PDK1-AKT1 phosphoactivation in the PIP3-PDK1-AKT1-mTOR pathway linked to cell growth and oncogenesis.
| S-EPMC8715220 | biostudies-literature
Project description:Alga-derived lipids represent an attractive potential source of biofuels. However, lipid accumulation in algae is a stress response tightly coupled to growth arrest, thereby imposing a major limitation on productivity. To identify master regulators of lipid accumulation and decipher the regulation of lipid biosynthetic pathway, we performed an integrative chromatin signature and transcriptomic analysis in the alga Chlamydomonas reinhardtii. Genome-wide histone modification profiling revealed remarkable differences in functional chromatin states between algae and higher eukaryotes and uncovered regulatory components at the core of lipid accumulation pathways. We identified the transcription factor PSR1 as a pivotal master switch that triggers cytosolic lipid hyper-accumulation an order of magnitude higher than stress regimens have achieved. Dissection of the PSR1 target network corroborates its central role in coordinating multiple stress responses. The comprehensive maps of functional chromatin signatures in a major clade of eukaryotic life and the discovery of a central regulator of algal lipid metabolism will facilitate targeted engineering strategies in microalgae.
2015-07-28 | GSE59629 | GEO
Project description:Single-cell RNA sequencing studies on gene co-expression patterns could yield important regulatory and functional insights, but have so far been limited by the confounding effects of differentiation and cell cycle. We apply a tailored experimental design that eliminates these confounders, and report thousands of intrinsically covarying gene pairs in mouse embryonic stem cells. These covariations form a network with biological properties, outlining known and novel gene interactions. We provide the first evidence that miRNAs naturally induce transcriptome-wide covariations and compare the relative importance of nuclear organization, transcriptional and post-transcriptional regulation in defining covariations. We find that nuclear organization has the greatest impact, and that genes encoding for physically interacting proteins specifically tend to covary, suggesting importance for protein complex formation. Our results lend support to the concept of post-transcriptional RNA operons, but we further present evidence that nuclear proximity of genes may provide substantial functional regulation in mammalian single cells.
| S-EPMC7595044 | biostudies-literature
Project description:In dicots, the key developmental process by which immature plastids differentiate into photosynthetically competent chloroplasts commences in the shoot apical meristem (SAM), within the shoot apex. Using laser-capture microdissection and single-cell RNA sequencing methodology, we studied the changes in the transcriptome along the chloroplast developmental pathway in the shoot apex of tomato seedlings. The analysis revealed the presence of transcripts for different chloroplast functions already in the stem cell-containing region of the SAM. Thereafter, an en masse up-regulation of genes encoding for various proteins occurs, including chloroplast ribosomal proteins and proteins involved in photosynthesis, photoprotection and detoxification of reactive oxygen species. The results highlight transcriptional events that operate during chloroplast biogenesis, leading to the rapid establishment of photosynthetic competence.
| S-EPMC5995843 | biostudies-literature
Project description:Jasmonate is an essential phytohormone involved in plant development and stress responses. Jasmonate perception occurs through the COI nuclear receptor allowing to target the JAZs repressors for degradation by the 26S proteasome. Consequently, repressed transcription factors are released and expression of JA-responsive genes is induced. In rice, three OsCOI genes have been identified, OsCOI1a and the closely related OsCOI1b homolog, and OsCOI2. While a role for OsCOI-1a and -1b genes was previously established in plant defense or leaf senescence, evidence for an important role of OsCOI2 in plant development, jasmonate-signaling and defence emerged only recently. To decipher the role of OsCOI2 in regulating jasmonate responses, we used rice mutant lines, edited both in the OsCOI1a and OsCOI1b genes, or in the OsCOI2 gene. Rice roots from WT and oscoi lines were treated by jasmonate to establish the molecular responses of each line, at the transcriptomic and metabolomic levels. RNA-seq data indicate that OsCOI2 is the main actor of the large transcriptional reprogramming observed after a JA challenge in rice roots. A series of transcription factors with an OsCOI2-dependent expression was identified, including transcription factors known to have a role in root development or stress response. An OsCOI2-dependent expression was detected for genes involved in specific processes or pathways such as photosynthesis, cell-growth and secondary metabolite biosynthesis (phenylpropanoids and diterpene phytoalexins). Functional redundancy between OsCOI1a/b and OsCOI2 can be shown for some genes, even if a lower response usually occurred in oscoi2 plants compared to oscoi1ab plants. Metabolic data revealed a shift from the primary metabolism to the secondary metabolism that is mainly OsCOI2-dependent. Differential accumulation of oryzalexins was also observed in oscoi lines.These data validate the major role of OsCOI2 in JA responses in rice roots. OsCOI2 is the major regulator of specialized metabolic pathways related to development and production of secondary metabolites. This study suggests that OsCOI2 controls the growth-defense trade-off in response to JA.
2024-09-17 | GSE262371 | GEO
Project description:Type 2 diabetes (T2D) is a long-term metabolic disorder disease characterized by high blood sugar and relative lack of insulin. Previous studies have demonstrated that Dendrobium has potent glucose-lowing effects and may serve as add-ons or alternatives to classic medications for T2D prevention and treatment, but the underlying molecular mechanisms were still unclear. We performed biochemical and transcriptional profiling (RNA sequencing [RNA-seq] and microRNA sequencing [miRNA-seq]) analyses on the pancreas and liver of Dendrobium fimbriatum extract (DFE)-fed diabetic rats and control animals. Our sequencing and experimental data indicated that DFE significantly alleviated diabetes symptoms through inhibiting inflammation and preventing islet cell apoptosis in diabetic pancreas. Transcription factors in Stat/nuclear factor κB (NF-κB)/Irf families combined with miR-148a/375/9a served as key regulators in the inflammation and apoptosis pathways under DFE administration. Meanwhile, DFE improved the energy metabolism, lipid transport, and oxidoreductase activity in the liver, and thus decreased lipid accumulation and lipotoxicity-induced hepatocyte apoptosis. Our findings revealed that DFE may serve as a potential therapeutic agent to prevent T2D, and also showed the combination of transcriptome profiling and regulatory network analysis could act as an effective approach for investigating potential molecular mechanisms of traditional Chinese medicine on diseases.
| S-EPMC6909217 | biostudies-literature
Project description:The master regulator p53 tumor-suppressor protein through coordination of several downstream target genes and upstream transcription factors controls many pathways important for tumor suppression. While it has been reported that some of the p53's functions are microRNA-mediated, it is not known as to how many other microRNAs might contribute to the p53-mediated tumorigenesis.Here, we use bioinformatics-based integrative approach to identify and prioritize putative p53-regulated miRNAs, and unravel the miRNA-based microregulation of the p53 master regulatory network. Specifically, we identify putative microRNA regulators of a) transcription factors that are upstream or downstream to p53 and b) p53 interactants. The putative p53-miRs and their targets are prioritized using current knowledge of cancer biology and literature-reported cancer-miRNAs.Our predicted p53-miRNA-gene networks strongly suggest that coordinated transcriptional and p53-miR mediated networks could be integral to tumorigenesis and the underlying processes and pathways.
| S-EPMC2289817 | biostudies-other
Project description:Pupal color polyphenism in Papilio butterflies, including green, intermediate, or brown, is an excellent study system for understanding phenotypic plasticity. Previous studies suggested that development of brown pupae may be controlled by a hormone called pupal-cuticle-melanizing-hormone (PCMH) which is synthesized and secreted from brain-suboesophageal ganglion and prothoracic ganglion complexes (Br-SG-TG1) during the pre-pupa stage. However, detailed molecular mechanisms of neuroendocrine regulation in pupal color development remain unknown. In this study, we integrated the expression profiles of transcriptome and proteome at pre-pupa stages [2 h after gut purge (T1) and 3 h after forming the garter around the body (T2)] and pigmentation stages [10 h after ecdysis (T3) and 24 h after ecdysis (T4)] to identify important genes and pathways underlying the development of green and brown pupa in the swallowtail butterfly Papilio xuthus. Combined comparisons of each developmental stage and each tissue under green and brown conditions, a total of 1042 differentially expressed genes (DEGs) and 430 different abundance proteins (DAPs) were identified. Weighted gene co-expression network analysis (WGCNA) and enrichment analysis indicate that these DEGs were mainly related to oxidation-reduction, structural constituent of cuticle, and pigment binding. Soft clustering by Mfuzz and enrichment analysis indicate that these DAPs are mainly involved in tyrosine metabolism, insect hormone biosynthesis, and melanogenesis. By homologous alignment, we further identified those genes encoding neuropeptides (51), GPCRs (116), G-proteins (8), cuticular proteins (226), chitinases (16), and chitin deacetylases (8) in the whole genome of P. xuthus and analyzed their expression profiles. Although we identified no gene satisfying with hypothesized expression profile of PCMH, we found some genes in the neuropeptide cascade showed differentially expressed under two pupal color conditions. We also found that Toll signaling pathway genes, juvenile hormone (JH) related genes, and multiple cuticular proteins play important roles in the formation of selective pupal colors during the prepupal-pupal transition. Our data also suggest that both green and brown pupa include complex pigment system that is regulated by genes involved in black, blue, and yellow pigments. Our results provide important insights into the evolution of pupal protective colors among swallowtail butterflies.
| S-EPMC8852814 | biostudies-literature