Ontology highlight
ABSTRACT:
PROVIDER: PRJDB10135 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Photoacclimation of unicellular algae allows for reversible changes in the number and/or effective absorption cross section of photosynthetic units on time scales of hours to days in response to changes in irradiance. The process involves an enigmatic signaling pathway from the plastid to the nucleus.Our results reveal, for the first time, a fundamental pathway of retrograde signal transduction in a eukaryotic photosynthetic alga.
2019-11-01 | GSE133301 | GEO
Project description:Complete plastid genomes of non-photosynthetic cryptomonads
| PRJDB6442 | ENA
Project description:Bigelowiella natans is a marine chlorarachniophyte whose plastid was acquired secondarily via endosymbiosis with a green alga. Integrating a photosynthetic endosymbiont within the host metabolism on route to plastid evolution would require the acquisition of strategies for coping with changes in light intensity and modifications of host genes to appropriately respond to changes in photosynthetic metabolism. To investigate the transcriptional response to light intensity in chlorarachniophytes, we conducted an RNA-seq experiment to identify differentially-expressed genes following four-hour shift to high or very-low light. A shift to high light altered the expression of over 2000 genes, many involved with photosynthesis, primary metabolism, and reactive-oxygen scavenging. These changes are related to an attempt to optimize photosynthesis and increase energy sinks for excess reductant, while minimizing photo-oxidative stress. A transfer to very-low light resulted in a lower photosynthetic performance and metabolic alteration, reflecting an energy-limited state. Genes located on the nucleomorph, the vestigial nucleus in the plastid, had few changes in expression in either light treatment, indicating this organelle has relinquished most transcriptional control to the nucleus. Overall, during plastid origin, both host and transferred endosymbiont genes evolved a harmonized transcriptional network to respond to a classic photosynthetic stress.
2019-01-01 | GSE115762 | GEO
Project description:Upon exposure to light, plant cells quickly acquire photosynthetic competence by converting pale etioplasts into green chloroplasts. This developmental transition involves the de novo biogenesis of the thylakoid system, and requires reprogramming of metabolism and gene expression. Etioplast-to-chloroplast differentiation involves massive changes in plastid ultrastructure, but how these changes are connected to specific changes in physiology, metabolism and expression of the plastid and nuclear genomes is poorly understood. Here a new experimental system in the dicotyledonous model plant tobacco (Nicotiana tabacum) that allows us to study the leaf de-etiolation process at the systems level. We have determined the accumulation kinetics of photosynthetic complexes, pigments, lipids and soluble metabolites, and recorded the dynamic changes in plastid ultrastructure and in the nuclear and plastid transcriptomes. Our data describe the greening process at high temporal resolution, resolve distinct genetic and metabolic phases during de-etiolation, and reveal numerous candidate genes that may be involved in light-induced chloroplast development and thylakoid biogenesis.
2019-03-09 | GSE128049 | GEO
Project description:Chloroplast function requires the coordinated action of nuclear- and chloroplast-derived proteins, including several hundred nuclear-encoded pentatricopeptide repeat (PPR) proteins that regulate plastid mRNA metabolism. Despite their large number and importance, regulatory mechanisms controlling PPR expression are poorly understood. Here we show that the Arabidopsis NOT4A ubiquitin-ligase positively regulates the expression of PROTON GRADIENT REGULATION 3 (PGR3), a PPR protein required for translating several thylakoid-localised photosynthetic components and ribosome subunits within chloroplasts. Loss of NOT4A function leads to a strong depletion of cytochrome b6f and NDH complexes, as well plastid 30S ribosomes, which reduces mRNA translation and negatively impacts photosynthetic capacity, causing pale-yellow and slow-growth phenotypes. Quantitative transcriptome and proteome analyses reveal that PGR3 is misregulated in not4a. We show that the molecular not4a defects mimic those of a pgr3 mutant, and that normal plastid function is restored through transgenic PGR3 expression. Our work identifies NOT4A as crucial for ensuring robust photosynthetic function during development and stress-response, through promoting PGR3 production and chloroplast translation.
2020-11-17 | GSE161571 | GEO
Project description:Unicellular eukaryotes and helminths Targeted loci environmental
| PRJNA495046 | ENA
Project description:The unicellular, free-living, nonphotosynthetic chlorophycean alga Polytomella parva, closely related to Chlamydomonas reinhardtii and Volvox carteri, contains colorless, starch-storing plastids. The P. parva plastids lack all light-dependent processes but maintain crucial metabolic pathways. The colorless alga also lacks a plastid genome, meaning no transcription or translation should occur inside the organelle. Here, using an algal fraction enriched in plastids as well as publicly available transcriptome data, we provide a proteomic characterization of the P. parva plastid, ultimately identifying several plastid proteins, both by mass spectrometry and bioinformatic analyses. Altogether these results led us to propose a plastid proteome for P. parva, i.e., a set of proteins that participate in carbohydrate metabolism; in the synthesis and degradation of starch, amino acids and lipids; in the biosynthesis of terpenoids and tetrapyrroles; in solute transport and protein translocation; and in redox homeostasis. This is the first detailed plastid proteome from a unicellular, free-living colorless alga.
2020-12-10 | PXD022051 | Pride
Project description:For establishing the photosynthetic apparatus plant cells must orchestrate the expression of genes encoded in both nucleus and chloroplast. Therefore a crosstalk between the two compartments is necessary. We employed a gene expression profiling approach in order to elucidate the changes in gene expression that occur at different stages of plastid development.
2020-02-07 | GSE144694 | GEO
Project description:For establishing the photosynthetic apparatus plant cells must orchestrate the expression of genes encoded in both nucleus and chloroplast. Therefore a crosstalk between the two compartments is necessary. We employed a gene expression profiling approach in order to elucidate the changes in gene expression that occur at different stages of plastid development.
2023-01-23 | GSE223240 | GEO
Project description:The plant plastid Clp machinery comprises a hetero-oligomeric ClpPRT proteolytic core, ATP-dependent ClpC,D chaperones and an adaptor protein, ClpS1. ClpS1 directs a subset of substrates to the Clp protease-chaperone complex for degradation, but substrate recognition and delivery mechanisms are unknown. Here we describe ClpF, a novel chloroplast adaptor. ClpF is only found in photosynthetic eukaryotes and contains uvr/C and YccV domains and an N-terminal domain conserved across ClpF homologs. We demonstrate that ClpF acts together with ClpS1 in substrate delivery to plastid ClpC chaperones. The molecular domain interactions of ClpF to ClpS1 and the ClpC chaperones were mapped, and in vivo interactions between ClpF and the Clp substrate glutamate t-RNA reductase (GluTR1) are demonstrated. Quantitative proteomics identified subtle molecular phenotype in a ClpF null mutant and we show that GluTR1 degradation is delayed in ClpF and ClpS1 Arabidopsis null mutants.
2019-04-09 | PXD002186 | Pride