Steroid Receptor Coactivator 1 is an Integrator of Glucose and NAD(+)/NADH Homeostasis
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE56843 | GEO | 2014/04/16
SECONDARY ACCESSION(S): PRJNA244751
REPOSITORIES: GEO
Similar Datasets
Project description:SRC-1 affects the expression of complex I of the mitochondrial electron transport chain, a set of enzymes responsible for the conversion of NADH to NAD(+). NAD(+) and NADH were subsequently identified as metabolites that underlie SRC-1's response to glucose deprivation. Knockdown of SRC-1 in glycolytic cancer cells abrogated their ability to grow in the absence of glucose consistent with SRC-1's role in promoting cellular adaptation to reduced glucose availability RNA profiling was used to examine the effects of SRC-1 perturbation on gene expression in the absence or presence of glucose.
2014-04-16 | E-GEOD-56843 | biostudies-arrayexpress
Project description:Knowledge about effects of cofactor perturbation on cellular metabolism is scarce with respect to Saccharopolyspora erythraea. The water-forming NADH oxidase (NOX) from Streptococcus pneumonia was expressed in S.erythraea E3, an important industrial strain for erythromycin production, at three different levels to investigate effects of intracellular redox status on secondary metabolism. NOX expression reduced the intracellular [NADH]/[NAD+] ratios significantly, although with a strong constitutive promoter NOX function was limited due to the shortage of oxygen. We demonstrated the negative correlation between [NADH]/[NAD+] ratios and biosynthesis of erythromycin in S.erythraea, but a positive correlation between the redox ratios and pigment production as well. We furthermore completed next-generation RNA sequencing of E3 and two NOX-expression strains. The transcription results showed that transfer processes of carbohydrates, DNA and chemical groups were altered resulting in metabolic shifts to supply more NADH for NOX fully functioning. Additionally, redox status affected transcription of several genes by allosteric effects on their transcription initiation. Specifically, transcriptional analysis along with enzymatic assay suggested that redox status influenced biosynthesis of erythromycin indirectly by allosteric effects on biosynthesis of the secondary messenger, c-di-GMP. The present work provides a basis for future cofactor manipulation in S.erythraea for further improvement of erythromycin production.
2020-08-04 | GSE144067 | GEO
Project description:When the yeast Saccharomyces cerevisiae is subjected to increasing glycolytic fluxes under aerobic conditions, there is a threshold value of the glucose uptake rate at which the metabolism shifts from being purely respiratory to mixed respiratory and fermentative. This shift is characterized by ethanol production, a phenomenon known as the Crabtree effect due to its analogy with lactate overflow in cancer cells. It is well known that at high glycolytic fluxes there is glucose repression of respiratory pathways resulting in a decrease in the respiratory capacity. Despite many years of detailed studies on this subject, it is not known whether the onset of the Crabtree effect (or overflow metabolism) is due to a limited respiratory capacity or caused by glucose-mediated repression of respiration. We addressed this issue by increasing respiration in S. cerevisiae by introducing a heterologous alternative oxidase, and observed reduced aerobic ethanol formation. In contrast, increasing non-respiratory NADH oxidation by overexpression of a water-forming NADH oxidase reduced aerobic glycerol formation. The metabolic response to elevated alternative oxidase occurred predominantly in the mitochondria, while NADH oxidase affected genes that catalyze cytosolic reactions. Moreover, NADH oxidase restored the deficiency of cytosolic NADH dehydrogenases in S. cerevisiae. These results indicate that NADH oxidase localizes in the cytosol, while alternative oxidase is directed to the mitochondria. The onset of aerobic ethanol formation is demonstrated to be a consequence of an imbalance in mitochondrial redox balancing. In addition to answering fundamental physiological questions, our findings are relevant for all biomass derived applications of S. cerevisiae. Experiment Overall Design: Heterologous gene expression in chemostats using Affymetrix Yeast Genome 2.0 arrays. Total RNA extraction and sample preparation, hybridization was done according to the manufacturer's protocol.
2008-06-14 | E-GEOD-6277 | biostudies-arrayexpress
Project description:When the yeast Saccharomyces cerevisiae is subjected to increasing glycolytic fluxes under aerobic conditions, there is a threshold value of the glucose uptake rate at which the metabolism shifts from being purely respiratory to mixed respiratory and fermentative. This shift is characterized by ethanol production, a phenomenon known as the Crabtree effect due to its analogy with lactate overflow in cancer cells. It is well known that at high glycolytic fluxes there is glucose repression of respiratory pathways resulting in a decrease in the respiratory capacity. Despite many years of detailed studies on this subject, it is not known whether the onset of the Crabtree effect (or overflow metabolism) is due to a limited respiratory capacity or caused by glucose-mediated repression of respiration. We addressed this issue by increasing respiration in S. cerevisiae by introducing a heterologous alternative oxidase, and observed reduced aerobic ethanol formation. In contrast, increasing non-respiratory NADH oxidation by overexpression of a water-forming NADH oxidase reduced aerobic glycerol formation. The metabolic response to elevated alternative oxidase occurred predominantly in the mitochondria, while NADH oxidase affected genes that catalyze cytosolic reactions. Moreover, NADH oxidase restored the deficiency of cytosolic NADH dehydrogenases in S. cerevisiae. These results indicate that NADH oxidase localizes in the cytosol, while alternative oxidase is directed to the mitochondria. The onset of aerobic ethanol formation is demonstrated to be a consequence of an imbalance in mitochondrial redox balancing. In addition to answering fundamental physiological questions, our findings are relevant for all biomass derived applications of S. cerevisiae. Keywords: Genetic Modification
2007-02-01 | GSE6277 | GEO
Project description:Human mesenchymal stem cells (hMSCs) promote endogenous tissue regeneration and have become a promising candidate for cell therapy. However, in vitro culture expansion of hMSCs induces a rapid decline of stem cell properties through replicative senescence. Here we characterize metabolic profiles of hMSCs during expansion. We show that alterations of cellular nicotinamide adenine dinucleotide (NAD+ /NADH) redox balance and activity of the Sirtuin (Sirt) family enzymes regulate cellular senescence of hMSCs. Treatment with NAD+ precursor nicotinamide increases the intracellular NAD+ level and re-balances the NAD+ /NADH ratio, with enhanced Sirt-1 activity in hMSCs at high passage, partially restores mitochondrial fitness and rejuvenates senescent hMSCs. By contrast, human fibroblasts exhibit limited senescence as their cellular NAD+ /NADH balance is comparatively stable during expansion. These results indicate a potential metabolic and redox connection to replicative senescence in adult stem cells and identify NAD+ as a metabolic regulator that distinguishes stem cells from mature cells. This study also suggests potential strategies to maintain cellular homeostasis of hMSCs in clinical applications.
2021-09-09 | PXD022395 | Pride
Project description:Physiological responses of Saccharopolyspora erythraea towards perturbation of intracellular NADH/NAD+
| PRJNA602682 | ENA
Project description:In mammals, circadian rhythms are entrained to the light cycle and drive daily oscillations in levels of NAD+ a co-substrate of the class III histone deacetylase SIRT1 that associates with clock transcription factors. While NAD+ also participates in redox reactions, the extent to which NAD(H) couples nutrient state with circadian transcriptional cycles remains unknown. Here we show that nocturnal animals subjected to time-restricted feeding of a calorie-restricted diet (TRF-CR) only during nighttime display reduced body temperature and elevated hepatic NADH during daytime. Genetic uncoupling of nutrient state from NADH redox state through transduction of the water-forming NADH oxidase from Lactobacillus brevis (LbNOX) increases daytime body temperature and blood and liver acyl-carnitines. LbNOX expression in TRF-CR mice induces oxidative gene networks controlled by BMAL1 and PPARa and suppresses amino acid catabolic pathways. Enzymatic analyses reveal that NADH inhibits SIRT1 in vitro, corresponding with reduced deacetylation of SIRT1 substrates during TRF-CR in vivo. Remarkably, Sirt1 liver nullizygous animals subjected to TRF-CR display persistent hypothermia even when NADH is oxidized by LbNOX. Our findings reveal that the hepatic NADH cycle links nutrient state to whole-body energetics through the rhythmic regulation of SIRT1.
2021-10-08 | GSE151281 | GEO
Project description:The rapidly growing family of coregulators of nuclear receptors includes coactivators that promote transcription and corepressors that harbor the opposing function. In recent years, coregulators have begun to emerge as important regulators of metabolic homeostasis, including the p160 Steroid Receptor Coactivator (SRC) family. Members of the SRC family have been ascribed important roles in control of gluconeogenesis in liver and fatty acid oxidation in skeletal muscle. To provide a deeper and more granular understanding of the metabolic impact of SRC family members, we have performed targeted metabolomics analysis of key metabolic byproducts of glucose, fatty acid, and amino acid metabolism in mice with global knockout of SRC-1, SRC-2, or SRC-3. We measured amino acids, acyl carnitines, and organic acids in five tissues with key metabolic functions (liver, heart, skeletal muscle, brain, plasma) isolated from SRC-1, -2, or -3 knockout mice and their wild-type littermates in the fed and fasted conditions, thereby unveiling unique metabolic functions of each SRC coactivator. Overall, we observed entire groups or subgroups of metabolites belonging to discrete metabolic pathways that were influenced in different tissues and/or feeding states due to ablation of individual SRC isoforms. Surprisingly, we identified very few metabolites that changed universally across the three SRC knockout models. These findings demonstrate that coactivator function has very limited redundancy even within the homologous SRC coactivator family. Furthermore, this work also demonstrates the use of metabolomics as a means for identifying novel metabolic regulatory functions of transcriptional coregulators.
2013-04-10 | MTBLS30 | MetaboLights
Project description:Previous findings have demonstrated that the NADH/NAD+ ratio has a strong impact on the glycolytic flux in C. glutamicum under anaerobic conditions in the absence of external electron acceptors. During an attempt to rewire anaerobic metabolism to achieve high yield formation of ethanol, we inactivated the malate dehydrogenase and lactate dehydrogenase in a C. glutamicum strain expressing pyruvate decarboxylase and alcohol dehydrogenase, to eliminate formation of the by-products succinate and lactate, respectively. This modification increased the yield of ethanol but had a negative effect on glycolysis, which we found to correlate with an elevated NADH/NAD+ ratio. The pyruvate dehydrogenase (PDH) of C. glutamicum is active under anaerobic conditions, and can potentially exacerbate the negative effect on glycolysis, due to NADH formation. To reduce PDH activity under anaerobic conditions, we decided to replace the gene encoding the E3 subunit of PDH with its Escherichia coli counterpart, as E. coli PDH has been reported to be functional under aerobic conditions only. The resultant strain JS133 produced far less acetate with a further increased ethanol production, however, the glycolytic flux was still low. After observing differences in glycolytic flux for JS133 on glucose and fructose, we speculated that the pentose phosphate pathway (PPP) might be involved in the reduced flux on glucose. To prove this, we deleted the zwf gene, encoding glucose-6-phosphate dehydrogenase, which is the entry point into PPP, and immediately observed a stimulating effect on glycolysis. Subsequent characterization revealed a direct correlation between the intracellular NADH/NAD+ and NADPH/NADP+ ratios under anoxic conditions. Based on these findings we managed to re-channel the metabolism of C. glutamicum successfully towards either to ethanol or D-lactate with 92% and 98% of the theoretical yield respectively, which is the highest yields for D-lactate production thus far reported in the literature.
2020-10-02 | GSE143977 | GEO
Project description:To study the overabundance of reducing equivalents, termed reductive stress, specifically for NADH reductive stress, we introduce a soluble transhydrogenase from E. coli (EcSTH) as a novel genetically encoded tool to promote NADH overproduction
2023-09-01 | GSE232115 | GEO