Sugar responsive regulatory network that controls organismal carbohydrate, amino acid and lipid homeostasis
Ontology highlight
ABSTRACT:
ORGANISM(S): Drosophila melanogaster
PROVIDER: GSE70980 | GEO | 2015/09/30
SECONDARY ACCESSION(S): PRJNA290042
REPOSITORIES: GEO
Similar Datasets
Project description:Maintaining metabolic homeostasis in response to fluctuating nutrient intake requires intricate coordination between tissues of multicellular animals. The insulin/glucagon axis is well known to hormonally coordinate organism-wide carbohydrate metabolism. The ChREBP/Mondo-Mlx transcription factors regulate glycolytic and lipogenic genes locally in hepatocytes and adipocytes, but its role in systemic metabolic homeostasis has remained poorly understood. We demonstrate that Mondo-Mlx controls gene activity in several peripheral tissues of Drosophila melanogaster, where it regulates nutrient digestion and transport as well as carbohydrate, amino acid and lipid metabolism. In addition to directly regulating metabolic genes Mondo-Mlx controls a regulatory network composed of the Activin ligand Dawdle and GLI similar transcription factor Sugarbabe. Dawdle and Sugarbabe contribute to the regulation of a subset of Mondo-Mlx-dependent processes, including sugar-induced de novo synthesis of serine and fatty acids. In summary, our study establishes Mondo-Mlx sugar sensor as a master regulator of organismal metabolic homeostasis upon sugar feeding.
2015-09-30 | GSE70979 | GEO
Project description:Maintaining metabolic homeostasis in response to fluctuating nutrient intake requires intricate coordination between tissues of multicellular animals. The insulin/glucagon axis is well known to hormonally coordinate organism-wide carbohydrate metabolism. The ChREBP/Mondo-Mlx transcription factors regulate glycolytic and lipogenic genes locally in hepatocytes and adipocytes, but its role in systemic metabolic homeostasis has remained poorly understood. We demonstrate that Mondo-Mlx controls gene activity in several peripheral tissues of Drosophila melanogaster, where it regulates nutrient digestion and transport as well as carbohydrate, amino acid and lipid metabolism. In addition to directly regulating metabolic genes Mondo-Mlx controls a regulatory network composed of the Activin ligand Dawdle and GLI similar transcription factor Sugarbabe. Dawdle and Sugarbabe contribute to the regulation of a subset of Mondo-Mlx-dependent processes, including sugar-induced de novo synthesis of serine and fatty acids. In summary, our study establishes Mondo-Mlx sugar sensor as a master regulator of organismal metabolic homeostasis upon sugar feeding.
2015-09-30 | GSE70978 | GEO
Project description:Sugar responsive regulatory network that controls organismal carbohydrate, amino acid and lipid homeostasis
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Project description:Yarrowia lipolytica is a promising microbial cell factory for the production of lipids to be used as fuels and chemicals, but there are few studies on regulation of its metabolism. Here we performed the first integrated data analysis of Y. lipolytica grown in carbon and nitrogen limited chemostat cultures. We first reconstructed a genome-scale metabolic model and used this for integrative analysis of multilevel omics data. Metabolite profiling and lipidomics was used to quantify the cellular physiology, while regulatory changes were measured using RNAseq. Analysis of the data showed that lipid accumulation in Y. lipolytica does not involve transcriptional regulation of lipid metabolism but is associated with regulation of amino-acid biosynthesis, resulting in redirection of carbon flux during nitrogen limitation from amino acids to lipids. Lipid accumulation in Y. lipolytica at nitrogen limitation is similar to the overflow metabolism observed in many other microorganisms, e.g. ethanol production by Sacchromyces cerevisiae at nitrogen limitation.
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Project description:The nitrogen-metabolic phosphotransferase system, PTS(Ntr), consists of the enzymes I(Ntr), NPr and IIA(Ntr) that are encoded by ptsP, ptsO, and ptsN, respectively. Due to the proximity of ptsO and ptsN to rpoN, the PTS(Ntr) system has been postulated to be closely related with nitrogen metabolism. To define the correlation between PTS(Ntr) and nitrogen metabolism, we performed ligand fishing with EIIA(Ntr) as a bait and revealed that D-glucosamine-6-phosphate synthase (GlmS) directly interacted with EIIA(Ntr). GlmS, which converts D-fructose-6-phosphate (Fru6P) into D-glucosamine-6-phosphate (GlcN6P), is a key enzyme producing amino sugars through glutamine hydrolysis. Amino sugar is an essential structural building block for bacterial peptidoglycan and LPS. We further verified that EIIA(Ntr) inhibited GlmS activity by direct interaction in a phosphorylation-state-dependent manner. EIIA(Ntr) was dephosphorylated in response to excessive nitrogen sources and was rapidly degraded by Lon protease upon amino sugar depletion. The regulation of GlmS activity by EIIA(Ntr) and the modulation of glmS translation by RapZ suggest that the genes comprising the rpoN operon play a key role in maintaining amino sugar homeostasis in response to nitrogen availability and the amino sugar concentration in the bacterial cytoplasm.
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