Marine sediment metagenome
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REPOSITORIES: ENA
Similar Datasets
Project description:Studies on temporal changes in the sediment oxygen consumption and bacterial community structure in a seasonally hypoxic enclosed bay, Omura Bay
| PRJDB7388 | ENA
Project description:This series compares the effects that two pharmacologically distinct ligands at the mitochondrial peripheral-type benzodiazepine receptor (Bzrp) has on gene expression in early mouse embryos cultured under different oxygen levels. Mouse embryos averaging 16-18 somite pairs were explanted on 9 d.p.c. and grown in culture under optimal oxygenation (21% oxygen, hyperbaric with respect to arterial blood = 80-100 mmHg). Most embryos (>90%) develop normally in over a 24h culture period. When embryos receive suboptimal oxygenation for 2.0h (5% oxygen, similar to venous blood = 38-40 mmHg) a high percentage of them (>60%) go on to develop abnormally or else fail. These hypoxic embryos are remediated with 5 uM PK11195 to ~25% malformation rate. Cultured embryos were exposed to different oxygen levels (5% or 21%) in the presence of the Bzrp ligands PK11195 (Bzrp antagonist) versus Ro5-4864 (Bzrp agonist). The sampling time was guided by p53 protein induction with hypoxia, and remediation with PK11195, at 4.0h of culture and exposures. Thus all measurements were on RNA from the prosencephalon collected 2.0h after start of the test period on 9 d.p.c. Keywords = peripheral benzodiazepine receptor Keywords = oxygen sensing Keywords = Bzrp ligands Keywords = PK11195 Keywords = Ro5-4864 Keywords = embryo Keywords = p53 protein induction
2010-06-09 | E-GEOD-1079 | biostudies-arrayexpress
Project description:The activation of the transcription factor Hypoxia-inducible factor-1 (HIF-1) plays an essential role in tumor development, tumor progression and resistance to chemo- and radiotherapy. In order to identify compounds targeting the HIF pathway, a small-molecule library was screened using a luciferase-driven HIF-1 reporter cell line under hypoxia. The high throughput screen led to the identification of a class of aminoalkyl-substituted compounds that inhibited hypoxia-induced HIF-1 target gene expression in human lung cancer cell lines at low nanomolar concentrations but did not affect expression levels of genes outside of the HIF-1 pathway. Lead structure BAY 87-2243 was found to inhibit HIF-1α protein accumulation under hypoxic conditions in NSCLC cell line H460 but had no effect on HIF-1α protein accumulation and HIF target gene expression in RCC4 cells lacking VHL activity or in H460 cells after inhibition of HIF prolyl hydroxylase activity. BAY 87-2243 had no effect on HIF-α-mRNA levels. Antitumor activity of BAY 87-2243 and suppression of HIF-1 target gene expression in vivo was demonstrated in a H460 xenograft model. BAY 87-2243 did not inhibit cell proliferation under standard conditions. However under glucose depletion, a condition favoring mitochondrial ATP generation as energy source, BAY 87-2243 inhibited cell proliferation in the nanomolar range. Further experiments revealed that BAY 87-2243 inhibits mitochondrial production of reactive oxygen species (ROS) by blocking complex I activity but has no effect on complex III activity. Lowering of mitochondrial ROS production to reduce hypoxia-induced HIF-1 activity in tumors might be an interesting therapeutic approach to overcome chemo- and radiotherapy-resistance of hypoxic tumors. We used microarrays to detail the global programme of gene expression that is induced in NSCLC cell line H460 upon hypoxia (16 h incubation at 1 % pO2) and evaluated a dose-dependent effect of our HIF-1-pathway inhibitor BAY 87-2243 on genes tthat are affected by hypoxia. Specificity of BAY 87-2243 for the suppression of HIF-1-mediated gene transcription on a genome-wide scale was evaluated by microarray hybridizations using Affymetrix GeneChip Human Gene 1.0 ST arrays. RNA from normoxic H460 cells and from hypoxic H460 cells incubated with 1, 10 and 100 nM BAY 87-2243 respectively was subjected to array hybridization. Of those 30 genes that were most strongly suppressed by 100 nM BAY 87-2243 in hypoxic H460 cells compared to DMSO-treated hypoxic H460 cells, virtually all of them are induced by prior hypoxia and most of these genes have been described in the literature as HIF-1 target genes
2012-12-08 | E-GEOD-42791 | biostudies-arrayexpress
Project description:This series compares the effects that two pharmacologically distinct ligands at the mitochondrial peripheral-type benzodiazepine receptor (Bzrp) has on gene expression in early mouse embryos cultured under different oxygen levels. Mouse embryos averaging 16-18 somite pairs were explanted on 9 d.p.c. and grown in culture under optimal oxygenation (21% oxygen, hyperbaric with respect to arterial blood = 80-100 mmHg). Most embryos (>90%) develop normally in over a 24h culture period. When embryos receive suboptimal oxygenation for 2.0h (5% oxygen, similar to venous blood = 38-40 mmHg) a high percentage of them (>60%) go on to develop abnormally or else fail. These hypoxic embryos are remediated with 5 uM PK11195 to ~25% malformation rate. Cultured embryos were exposed to different oxygen levels (5% or 21%) in the presence of the Bzrp ligands PK11195 (Bzrp antagonist) versus Ro5-4864 (Bzrp agonist). The sampling time was guided by p53 protein induction with hypoxia, and remediation with PK11195, at 4.0h of culture and exposures. Thus all measurements were on RNA from the prosencephalon collected 2.0h after start of the test period on 9 d.p.c. Keywords = peripheral benzodiazepine receptor Keywords = oxygen sensing Keywords = Bzrp ligands Keywords = PK11195 Keywords = Ro5-4864 Keywords = embryo Keywords = p53 protein induction Keywords: ordered
2004-03-11 | GSE1079 | GEO
Project description:The activation of the transcription factor Hypoxia-inducible factor-1 (HIF-1) plays an essential role in tumor development, tumor progression and resistance to chemo- and radiotherapy. In order to identify compounds targeting the HIF pathway, a small-molecule library was screened using a luciferase-driven HIF-1 reporter cell line under hypoxia. The high throughput screen led to the identification of a class of aminoalkyl-substituted compounds that inhibited hypoxia-induced HIF-1 target gene expression in human lung cancer cell lines at low nanomolar concentrations but did not affect expression levels of genes outside of the HIF-1 pathway. Lead structure BAY 87-2243 was found to inhibit HIF-1α protein accumulation under hypoxic conditions in NSCLC cell line H460 but had no effect on HIF-1α protein accumulation and HIF target gene expression in RCC4 cells lacking VHL activity or in H460 cells after inhibition of HIF prolyl hydroxylase activity. BAY 87-2243 had no effect on HIF-α-mRNA levels. Antitumor activity of BAY 87-2243 and suppression of HIF-1 target gene expression in vivo was demonstrated in a H460 xenograft model. BAY 87-2243 did not inhibit cell proliferation under standard conditions. However under glucose depletion, a condition favoring mitochondrial ATP generation as energy source, BAY 87-2243 inhibited cell proliferation in the nanomolar range. Further experiments revealed that BAY 87-2243 inhibits mitochondrial production of reactive oxygen species (ROS) by blocking complex I activity but has no effect on complex III activity. Lowering of mitochondrial ROS production to reduce hypoxia-induced HIF-1 activity in tumors might be an interesting therapeutic approach to overcome chemo- and radiotherapy-resistance of hypoxic tumors. We used microarrays to detail the global programme of gene expression that is induced in NSCLC cell line H460 upon hypoxia (16 h incubation at 1 % pO2) and evaluated a dose-dependent effect of our HIF-1-pathway inhibitor BAY 87-2243 on genes tthat are affected by hypoxia.
2012-12-08 | GSE42791 | GEO
Project description:Genomic response of cruician carp to anoxia treatmnet and re-oxygenation at two temperatures was measured using two channels microarray.
2014-06-01 | E-MTAB-2516 | biostudies-arrayexpress
Project description:We report the effect of oxygenation state in lactose grown escherichia coli producing recombinant proteins. To shed more light on the mechanistic correlation between the uptake of lactose and dissolved oxygen, a comprehensive study has been undertaken with the E. coli BL21 (DE3) strain. Differences in consumption pattern of lactose, metabolites, biomass and product formation due to aerobiosis have been investigated. Transcriptomic profiling of metabolic changes due to aerobic process and microaerobic process during protein formation phase has been studied and the results provide a deeper understanding of protein production in E. coli BL21 (DE3) strains with lactose based promoter expression systems.This study also provides a scientific understanding of escherichia coli metabolism upon oxygen fluctuations.
2020-05-18 | GSE135698 | GEO
Project description:Change in community structure of sulfate-reducing bacteria in seasonally hypoxic bay sediments
| PRJDB6712 | ENA
Project description:Despite anatomical similarities, there are differences in susceptibility to cardiovascular disease (CVD) between primates; humans are prone to myocardial ischemia, while chimpanzees are prone to myocardial fibrosis. Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) allow for direct inter-species comparisons of the gene regulatory response to CVD-relevant perturbations such as oxygen deprivation, a consequence of ischemia. To gain insight into the evolution of disease susceptibility, we characterized gene expression levels in iPSC-CMs in humans and chimpanzees, before and after hypoxia and re-oxygenation. The transcriptional response to hypoxia is generally conserved across species, yet we were able to identify hundreds of species-specific regulatory responses including in genes previously associated with CVD. The 1,920 genes that respond to hypoxia in both species are enriched for loss-of-function intolerant genes; but are depleted for expression quantitative trait loci and cardiovascular-related genes. Our results indicate that response to hypoxic stress is highly conserved in humans and chimpanzees.
2019-04-10 | GSE117192 | GEO
Project description:Myocardial infarctions are caused by coronary occlusions that deprive downstream myocardial tissue of oxygenated blood, leading to localized necrosis of cardiac myocytes. Hypoxic injury drives a remodeling process in which cardiac fibroblasts activate and synthesize matrix proteins to form a scar. During this process, cardiac cells are exposed to an oxygen gradient at the infarct border zone that transitions from 0% oxygen at the site of injury to 10% oxygen in healthy myocardium. However, the impact of any crosstalk between hypoxic cardiac fibroblasts and neighboring, normoxic (10% oxygen) cardiac cells is unexplored because conventional research tools cannot re-create spatially heterogeneous oxygen landscapes. Here, we used a microfluidic device to co-culture hypoxic cardiac fibroblasts with (1) normoxic cardiac fibroblasts or (2) normoxic human induced pluripotent stem cell (hiPSC)-derived cardiac myocytes. We then compared their transcriptome to the same cells cultured in uniform hypoxia or normoxia. These data contribute to more advanced understanding of how oxygen-dependent crosstalk between cardiac cells impacts the wound healing process post-myocardial infarction.
2024-06-30 | GSE254962 | GEO