Background mutagenesis during prolonged exposure
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB34943 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Prolonged cultivation (>25 generations) of Saccharomyces cerevisiae in aerobic, maltose-limited chemostat cultures led to profound physiological changes. Maltose hypersensitivity was observed when cells from prolonged cultivations were suddenly exposed to excess maltose. This substrate hypersensitivity was evident from massive cell lysis and loss of viability. During prolonged cultivation at a fixed specific growth rate, the affinity for the growth-limiting nutrient (i.e., maltose) increased, as evident from a decreasing residual maltose concentration. Furthermore, the capacity of maltose-dependent proton uptake increased up to 2.5-fold during prolonged cultivation. Genome-wide transcriptome analysis showed that the increased maltose transport capacity was not primarily due to increased transcript levels of maltose-permease genes upon prolonged cultivation. We propose that selection for improved substrate affinity (ratio of maximum substrate consumption rate and substrate saturation constant) in maltose-limited cultures leads to selection for cells with an increased capacity for maltose uptake. At the same time, the accumulative nature of maltose-proton symport in S. cerevisiae leads to unrestricted uptake when maltose-adapted cells are exposed to a substrate excess. These changes were retained after isolation of individual cell lines from the chemostat cultures and nonselective cultivation, indicating that mutations were involved. The observed trade-off between substrate affinity and substrate tolerance may be relevant for metabolic engineering and strain selection for utilization of substrates that are taken up by proton symport. Experiment Overall Design: In a recent study (25) we analyzed glucose efflux upon exposure of S. cerevisiae to excess maltose, with yeast cells originating from âyoungâ chemostat cultures (<20 generations). In these experiments no cell lysis was observed upon exposure to excess maltose. However, in further work on this subject, we observed an apparent effect of chemostat culture age on transport capacity. The aim of the present study was to further investigate the effect of prolonged maltose-limited chemostat cultivation on the physiology of S. cerevisiae. To this end we monitored the affinity for maltose, genome-wide transcript levels, activities of key enzymes, and physiological responses to maltose excess during long-term cultivation in maltose-limited chemostat cultures. Experiment Overall Design: Jansen, M. L. A., J. H. de Winde, and J. T. Pronk. 2002. Hxt-carrier-mediated glucose efflux upon exposure of Saccharomyces cerevisiaeSaccharomyces cerevisiae to excess maltose. Appl. Environ. Microbiol. 68:4259-4265.
2008-06-16 | E-GEOD-8897 | biostudies-arrayexpress
Project description:Kaposi sarcoma-associated herpesvirus (KSHV) inflammatory cytokine syndrome (KICS) is a newly described chronic inflammatory disease condition caused by KSHV infection and is characterized by high KSHV viral load and sustained elevations of serum KSHV-encoded IL-6 (vIL-6) and human IL-6 (hIL-6). KICS has significant immortality and possesses greater risks of having other complications, which include malignancies. Although prolonged inflammatory vIL-6 exposure by persistent KSHV infection is expected to have key roles in subsequent disease development, the biological effects of prolonged vIL-6 exposure remain elusive. Using thiol(SH)-Linked Alkylation for the Metabolic Sequencing (SLAM-seq) and Cleavage Under Target & Release Using Nuclease (CUT&RUN) analysis, we studied the effect of prolonged vIL-6 exposure in chromatin landscape and resulting cytokine production. The studies showed that prolonged vIL-6 exposure increased Bromodomain containing 4 (BRD4) and histone H3 lysine 27 acetylation (H3K27Ac) co-occupancies on chromatin, and the recruitment sites were frequently co-localized with poised RNA polymerase II with associated enzymes. Increased BRD4 recruitment on promoters was associated with increased and prolonged p65 (RelA) binding after the LPS stimulation. The p65 binding resulted in quicker and sustained transcription bursts from the promoters; this mechanism increased total amounts of hIL-6 and IL-10 in tissue culture. Pretreatment with the BRD4 inhibitor, OTX015, eliminated the enhanced inflammatory cytokine production. These findings suggest that persistent vIL-6 exposure may establish a chromatin landscape favorable for the reactivation of inflammatory responses in monocytes. This epigenetic memory may explain the greater risk of chronic inflammatory disease development in KSHV-infected individuals.
2023-08-08 | GSE232843 | GEO
Project description:Kaposi sarcoma-associated herpesvirus (KSHV) inflammatory cytokine syndrome (KICS) is a newly described chronic inflammatory disease condition caused by KSHV infection and is characterized by high KSHV viral load and sustained elevations of serum KSHV-encoded IL-6 (vIL-6) and human IL-6 (hIL-6). KICS has significant immortality and possesses greater risks of having other complications, which include malignancies. Although prolonged inflammatory vIL-6 exposure by persistent KSHV infection is expected to have key roles in subsequent disease development, the biological effects of prolonged vIL-6 exposure remain elusive. Using thiol(SH)-Linked Alkylation for the Metabolic Sequencing (SLAM-seq) and Cleavage Under Target & Release Using Nuclease (CUT&RUN) analysis, we studied the effect of prolonged vIL-6 exposure in chromatin landscape and resulting cytokine production. The studies showed that prolonged vIL-6 exposure increased Bromodomain containing 4 (BRD4) and histone H3 lysine 27 acetylation (H3K27Ac) co-occupancies on chromatin, and the recruitment sites were frequently co-localized with poised RNA polymerase II with associated enzymes. Increased BRD4 recruitment on promoters was associated with increased and prolonged p65 (RelA) binding after the LPS stimulation. The p65 binding resulted in quicker and sustained transcription bursts from the promoters; this mechanism increased total amounts of hIL-6 and IL-10 in tissue culture. Pretreatment with the BRD4 inhibitor, OTX015, eliminated the enhanced inflammatory cytokine production. These findings suggest that persistent vIL-6 exposure may establish a chromatin landscape favorable for the reactivation of inflammatory responses in monocytes. This epigenetic memory may explain the greater risk of chronic inflammatory disease development in KSHV-infected individuals.
2023-08-08 | GSE233323 | GEO
Project description:Kaposi sarcoma-associated herpesvirus (KSHV) inflammatory cytokine syndrome (KICS) is a newly described chronic inflammatory disease condition caused by KSHV infection and is characterized by high KSHV viral load and sustained elevations of serum KSHV-encoded IL-6 (vIL-6) and human IL-6 (hIL-6). KICS has significant immortality and possesses greater risks of having other complications, which include malignancies. Although prolonged inflammatory vIL-6 exposure by persistent KSHV infection is expected to have key roles in subsequent disease development, the biological effects of prolonged vIL-6 exposure remain elusive. Using thiol(SH)-Linked Alkylation for the Metabolic Sequencing (SLAM-seq) and Cleavage Under Target & Release Using Nuclease (CUT&RUN) analysis, we studied the effect of prolonged vIL-6 exposure in chromatin landscape and resulting cytokine production. The studies showed that prolonged vIL-6 exposure increased Bromodomain containing 4 (BRD4) and histone H3 lysine 27 acetylation (H3K27Ac) co-occupancies on chromatin, and the recruitment sites were frequently co-localized with poised RNA polymerase II with associated enzymes. Increased BRD4 recruitment on promoters was associated with increased and prolonged p65 (RelA) binding after the LPS stimulation. The p65 binding resulted in quicker and sustained transcription bursts from the promoters; this mechanism increased total amounts of hIL-6 and IL-10 in tissue culture. Pretreatment with the BRD4 inhibitor, OTX015, eliminated the enhanced inflammatory cytokine production. These findings suggest that persistent vIL-6 exposure may establish a chromatin landscape favorable for the reactivation of inflammatory responses in monocytes. This epigenetic memory may explain the greater risk of chronic inflammatory disease development in KSHV-infected individuals.
2023-08-08 | GSE233119 | GEO
Project description:Early biomarkers of renal damage due to prolonged exposure to embedded metal.
| PRJNA841636 | ENA
Project description:Background: Prolonged exposure to toxic heavy metals leads to deleterious health outcomes such as kidney injury and irreversible progression to chronic kidney disease. For example, veterans return from the battlefield with increasing amounts of retained metal fragments. Certain community water sources in the US are contaminated with varying levels of heavy metals, including uranium and lead. One of the key challenges is to detect damage to kidney tissue before glomerular filtration rate is affected. Methods: High-throughput transcriptomics (HTT) has recently been demonstrated have high sensitivity and specificity as a rapid and cost-effective assay for detecting tissue toxicity. To better understand the molecular signature of early kidney damage, we performed RNA-seq analysis on renal tissue using a rat model of soft tissue-embedded metal exposure. We them performed small RNA-seq analysis on serum samples from the same animals in an effort to identify miRNA biomarkers of kidney damage. Results: We found that metals, especially lead and depleted uranium, induces oxidative damage that mainly cause dysregulated mitochondrial gene expression. Utilizing publicly available single-cell RNA-seq datasets, we demonstrate that deep learning-based cell type decomposition effectively identified cells within the kidney that were affected by metal exposure. By combining random forest feature selection and statistical methods, we further identify miRNA-423 as a promising early systemic marker of kidney injury. Conclusion: Our data suggests that combining HTT and deep learning represents a promising approach for identifying cell injury in kidney tissue. We propose miRNA-423 as a potential serum biomarker for early detection of kidney injury.
2022-12-01 | GSE203624 | GEO
Project description:Effect of prolonged exposure to normoxia on miRNA expression of primary mouse chondrocytes
| PRJNA522876 | ENA
Project description:Prolonged pause during follicle growth contributes to offspring throughout reproductive lifespan
| PRJNA1135116 | ENA
Project description:Chromatin remodeler INO80 is essential for cocaine craving during prolonged withdrawal
| PRJNA489783 | ENA
Project description:The molecular mechanisms associated with spaceflight-induced biological adaptations that may affect many healthy tissue functions remain poorly understood. In this study, we analyzed temporal changes in the serum proteome of six astronauts during prolonged spaceflight missions using quantitative comprehensive proteome analysis performed with the data-independent acquisition method of mass spectrometry (DIA-MS). DIA-MS successfully identified 624 non-redundant proteins in sera and further quantitative analysis for each sampling point provided information on serum protein profiles closely related to several time points before (Pre-), during (In-), and after (Post-) spaceflight.
2024-01-22 | PXD044609 | JPOST Repository