Phaeodactylum tricornutum
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ABSTRACT:
PROVIDER: PRJNA113287 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Diatoms, which are important planktons widespread in various aquatic environments, are believed to play a vital role in primary production as well as silica cycling. The genomes of the pennate diatom Phaeodactylum tricornutum and the centric diatom Thalassiosira pseudonana have been sequenced, revealing some characteristics of the diatomsâ mosaic genome as well as some features of their fatty acid metabolism and urea cycle, and indicating their unusual properties. To identify microRNAs (miRNAs) from P. tricornutum and to study their probable roles in nitrogen and silicon metabolism, we constructed and sequenced small RNA (sRNA) libraries from P. tricornutum under normal (PT1), nitrogen-limited (PT2) and silicon-limited (PT3) conditions. A total of 13 miRNAs were identified. They were probable P. tricornutum-specific novel miRNAs. These miRNAs were differentially expressed in PT1, PT2 and PT3, and their potential targets were involved in various processes. Our results indicated that P. tricornutum contained novel miRNAs that differed from miRNAs of other organisms and that they might play important regulator roles in P. tricornutum metabolism.
2011-08-08 | GSE29321 | GEO
Project description:Diatoms, which are important planktons widespread in various aquatic environments, are believed to play a vital role in primary production as well as silica cycling. The genomes of the pennate diatom Phaeodactylum tricornutum and the centric diatom Thalassiosira pseudonana have been sequenced, revealing some characteristics of the diatomsâ mosaic genome as well as some features of their fatty acid metabolism and urea cycle, and indicating their unusual properties. To identify microRNAs (miRNAs) from P. tricornutum and to study their probable roles in nitrogen and silicon metabolism, we constructed and sequenced small RNA (sRNA) libraries from P. tricornutum under normal (PT1), nitrogen-limited (PT2) and silicon-limited (PT3) conditions. A total of 13 miRNAs were identified. They were probable P. tricornutum-specific novel miRNAs. These miRNAs were differentially expressed in PT1, PT2 and PT3, and their potential targets were involved in various processes. Our results indicated that P. tricornutum contained novel miRNAs that differed from miRNAs of other organisms and that they might play important regulator roles in P. tricornutum metabolism. Constructing and sequencing small RNA (sRNA) libraries from P. tricornutum under normal (PT1), nitrogen-limited (PT2) and silicon-limited (PT3) conditions
2011-08-08 | E-GEOD-29321 | biostudies-arrayexpress
Project description:Diatoms are prominent marine microalgae, interesting not only from an ecological point of view, but also for their possible use for biotechnology applications. They can be cultivated in phototrophic conditions, using sunlight as the only energy source. Some diatoms, however, can also grow in mixotrophic mode, where both light and external reduced carbon contribute to biomass accumulation. In this study, we investigated the consequences of mixotrophy on the growth and metabolism of the pennate diatom Phaeodactylum tricornutum, using glycerol as a source of reduced carbon. Transcriptomic, metabolomic and physiological data indicate that glycerol affects the central-carbon, carbon-storage and lipid metabolism of the diatom. In particular, glycerol addition mimics some typical responses of nitrogen limitation on lipid metabolism at the level of TAG accumulation and fatty acid composition. However, this compound does not diminish photosynthetic activity and cell growth, at variance with nutrient limitation, revealing essential aspects of the metabolic flexibility of these microalgae and suggesting possible biotechnological applications of mixotrophy.
2017-03-31 | GSE91004 | GEO
Project description:Diatoms played an essential role in marine primary productivity. Polysaccharide chrysolaminarin and neutral lipid, mainly TAG, were necessary carbon fixation in diatom Phaeodactylum tricornutum. Our study speculated on the metabolism pathway of chrysolaminarin, fatty acid, fatty acid β-oxidation and TAG. Transcriptional levels coordinated with carbon fixation metabolism pathway were conjoint analysis in this study.
2022-08-03 | GSE210141 | GEO
Project description:Diatoms represent one of the largest groups of Stramenopiles. In the phytoplankton biodiversity, they dominate oceanic and freshwater ecosystems, and contribute significantly to biogeochemical cycles. They are primary producers at the base of food webs, capturing dissolved CO2, inorganic nitrogen, phosphorus, sulfur, etc., and are important carriers of carbon and silicon to the ocean interior. Whereas extensive studies of P. tricornutum response to a lack of nitrogen have been reported from transcriptomics to metabolomics and lipidomics, changes occurring at the proteome level are still missing. Here we aimed at providing a reference dataset, corresponding to the proteomic changes occurring when Phaeodactylum tricornutum cells were cultivated in either a nitrogen-rich or a nitrogen-poor medium.
2022-09-29 | PXD033328 | Pride
Project description:Photosynthetic diatoms are exposed to rapid and unpredictable changes in irradiance and spectral quality, and must be able to adapt their light harvesting systems to varying light conditions. Molecular mechanisms behind light acclimation in diatoms are largely unknown. We set out to investigate the mechanisms of high light acclimation in Phaeodactylum tricornutum using an integrated approach involving global transcriptional profiling, metabolite profiling and variable fluorescence technique. Algae cultures were acclimated to low light (LL), after which the cultures were transferred to high light (HL). Molecular, metabolic and physiological responses were studied at time points 0.5 h, 3 h, 6 h, 12 h, 24 h and 48 h after transfer to HL conditions. The integrated results indicate that the acclimation mechanisms in diatoms can be divided into an initial response phase (0.5 h), an intermediate acclimation phase (3-12 h) and a late acclimation phase (12-48 h). The initial phase is recognized by strong and rapid regulation of genes encoding proteins involved in photosynthesis, pigment metabolism and reactive oxygen species (ROS) scavenging systems. A significant increase in light protecting metabolites occur together with the induction of transcriptional processes involved in protection of cellular structures at this early phase. During the following phases, the metabolite profiling display a pronounced decrease in light harvesting pigments, whereas the variable fluorescence measurements show that the photosynthetic capacity increases strongly during the late acclimation phase. We show that P. tricornutum is capable of swift and efficient execution of photoprotective mechanisms, followed by changes in the composition of the photosynthetic machinery that enable the diatoms to utilize the excess energy available in HL. Central molecular players in light protection and acclimation to high irradiances have been identified.
2009-11-06 | GSE17237 | GEO
Project description:Photosynthetic diatoms are exposed to rapid and unpredictable changes in irradiance and spectral quality, and must be able to adapt their light harvesting systems to varying light conditions. Molecular mechanisms behind light acclimation in diatoms are largely unknown. We set out to investigate the mechanisms of high light acclimation in Phaeodactylum tricornutum using an integrated approach involving global transcriptional profiling, metabolite profiling and variable fluorescence technique. Algae cultures were acclimated to low light (LL), after which the cultures were transferred to high light (HL). Molecular, metabolic and physiological responses were studied at time points 0.5 h, 3 h, 6 h, 12 h, 24 h and 48 h after transfer to HL conditions. The integrated results indicate that the acclimation mechanisms in diatoms can be divided into an initial response phase (0.5 h), an intermediate acclimation phase (3-12 h) and a late acclimation phase (12-48 h). The initial phase is recognized by strong and rapid regulation of genes encoding proteins involved in photosynthesis, pigment metabolism and reactive oxygen species (ROS) scavenging systems. A significant increase in light protecting metabolites occur together with the induction of transcriptional processes involved in protection of cellular structures at this early phase. During the following phases, the metabolite profiling display a pronounced decrease in light harvesting pigments, whereas the variable fluorescence measurements show that the photosynthetic capacity increases strongly during the late acclimation phase. We show that P. tricornutum is capable of swift and efficient execution of photoprotective mechanisms, followed by changes in the composition of the photosynthetic machinery that enable the diatoms to utilize the excess energy available in HL. Central molecular players in light protection and acclimation to high irradiances have been identified. The experiment was designed as a time series, with diatom cultures were harvested at time points 0.5 h, 3 h, 6 h, 12 h, 24 h and 48 h after transfer to high light conditions. The reference samples were kept at low light and harvested in parallel with the treated samples. Three biological replicates were harvested for all samples.
2009-11-05 | E-GEOD-17237 | biostudies-arrayexpress
Project description:Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum.
| PRJNA356626 | ENA
Project description:Periodic light–dark cycles govern the timing of basic biological processes in organisms inhabiting land as well as the sea, where life evolved. Although prominent marine phytoplanktonic organisms such as diatoms show robust diel rhythms, the mechanisms regulating these processes are still obscure. By characterizing a Phaeodactylum tricornutum bHLH-PAS nuclear protein, hereby named RITMO1, we shed light on the regulation of the daily life of diatoms. Alteration of RITMO1 expression levels and timing by ectopic overexpression results in lines with deregulated diurnal gene expression profiles compared with the wild-type cells. Reduced gene expression oscillations are also observed in these lines in continuous darkness, showing that the regulation of rhythmicity by RITMO1 is not directly dependent on light inputs. We also describe strong diurnal rhythms of cellular fluorescence in wild-type cells, which persist in continuous light conditions, indicating the existence of an endogenous circadian clock in diatoms. The altered rhythmicity observed in RITMO1 overexpression lines in continuous light supports the involvement of this protein in circadian rhythm regulation. Phylogenetic analysis reveals a wide distribution of RITMO1-like proteins in the genomes of diatoms as well as in other marine algae, which may indicate a common function in these phototrophs. This study adds elements to our understanding of diatom biology and offers perspectives to elucidate timekeeping mechanisms in marine organisms belonging to a major, but under-investigated, branch of the tree of life.
2019-05-24 | GSE112267 | GEO
Project description:Periodic light–dark cycles govern the timing of basic biological processes in organisms inhabiting land as well as the sea, where life evolved. Although prominent marine phytoplanktonic organisms such as diatoms show robust diel rhythms, the mechanisms regulating these processes are still obscure. By characterizing a Phaeodactylum tricornutum bHLH-PAS nuclear protein, hereby named RITMO1, we shed light on the regulation of the daily life of diatoms. Alteration of RITMO1 expression levels and timing by ectopic overexpression results in lines with deregulated diurnal gene expression profiles compared with the wild-type cells. Reduced gene expression oscillations are also observed in these lines in continuous darkness, showing that the regulation of rhythmicity by RITMO1 is not directly dependent on light inputs. We also describe strong diurnal rhythms of cellular fluorescence in wild-type cells, which persist in continuous light conditions, indicating the existence of an endogenous circadian clock in diatoms. The altered rhythmicity observed in RITMO1 overexpression lines in continuous light supports the involvement of this protein in circadian rhythm regulation. Phylogenetic analysis reveals a wide distribution of RITMO1-like proteins in the genomes of diatoms as well as in other marine algae, which may indicate a common function in these phototrophs. This study adds elements to our understanding of diatom biology and offers perspectives to elucidate timekeeping mechanisms in marine organisms belonging to a major, but under-investigated, branch of the tree of life.
2019-05-24 | GSE112266 | GEO