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GSE47983
Saccharomyces cerevisiae
12 Downloadable Samples
Affymetrix Yeast Genome S98 Array (ygs98)
Description
Cytosolic acetyl-coenzyme A is a precursor for many biotechnologically relevant compounds produced by Saccharomyces cerevisiae. In this yeast, cytosolic acetyl-CoA synthesis and growth strictly depend on expression of either the Acs1 or Acs2 isoenzyme of acetyl-CoA synthetase (ACS). Since hydrolysis of ATP to AMP and pyrophosphate in the ACS reaction constrains maximum yields of acetyl-CoA-derived products, this study explores replacement of ACS by two ATP-independent pathways for acetyl-CoA synthesis. After evaluating expression of different bacterial genes encoding acetylating acetaldehyde dehydrogenase (A-ALD) and pyruvate-formate lyase (PFL), acs1 acs2 S. cerevisiae strains were constructed in which A-ALD or PFL successfully replaced ACS. In A-ALD-dependent strains, aerobic growth rates of up to 0.27 h-1 were observed, while anaerobic growth rates of PFL-dependent S. cerevisiae (0.21 h-1) were stoichiometrically coupled to formate production. In glucose-limited chemostat cultures, intracellular metabolite analysis did not reveal major differences between A-ALD-dependent and reference strains. However, biomass yields on glucose of A-ALD- and PFL-dependent strains were lower than those of the reference strain. Transcriptome analysis suggested that reduced biomass yields were caused by acetaldehyde and formate in A-ALD- and PFL-dependent strains, respectively. Transcript profiles also indicated that a previously proposed role of Acs2 in histone acetylation is probably linked to cytosolic acetyl-CoA levels rather than to direct involvement of Acs2 in histone acetylation. While, for the first time, demonstrating that yeast ACS can be fully replaced by alternative reactions, this study demonstrates that further modifications are needed to achieve optimal in vivo efficiencies of the supply of acetyl-CoA as product precursor.
Publication Title
Replacement of the Saccharomyces cerevisiae acetyl-CoA synthetases by alternative pathways for cytosolic acetyl-CoA synthesis.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 6 Downloadable Samples
Illumina HiSeq 2500
Description
The energetic (ATP) cost of biochemical pathways critically determines the maximum yield of metabolites of vital or commercial relevance. Cytosolic acetyl-CoA is a key precursor for biosynthesis in eukaryotes and for many industrially relevant product pathways that have been introduced into Saccharomyces cerevisiae, such as isoprenoids or lipids. In this yeast, synthesis of cytosolic acetyl-CoA via acetyl-CoA synthetase (ACS) involves hydrolysis of ATP to AMP and pyrophosphate. Here, we demonstrate that expression and assembly in the yeast cytosol of a pyruvate dehydrogenase complex (PDH) from Enterococcus faecalis can fully replace the ACS-dependent pathway for cytosolic acetyl-CoA synthesis. In vivo activity of E. faecalis PDH required the simultaneous expression of E. faecalis genes encoding its E1a, E1ß, E2 and E3 subunits, as well as genes involved in lipoylation of E2 and addition of lipoate to growth media. A strain lacking ACS, that expressed these E. faecalis genes, grew at near-wild-type rates on glucose synthetic medium supplemented with lipoate, under aerobic and anaerobic conditions. A physiological comparison of the engineered strain and an isogenic Acs+ reference strain showed small differences in biomass yields and metabolic fluxes. Cellular fractionation and gel filtration studies revealed that the E. faecalis PDH subunits were assembled in the yeast cytosol, with a subunit ratio and enzyme activity similar to values reported for PDH purified from E. faecalis. This study indicates that cytosolic expression and assembly of PDH in eukaryotic industrial micro-organisms is a promising option for minimizing the energy costs of precursor supply in acetyl-CoA-dependent product pathways. Overall design: For both strains - mutant strain IMY104 and reference strain CEN.PK113-7D'' three independent chemostat cultures were performed. Each of the chemosta was sampled for transcriptome analysis. Samples were processed as described below.
Publication Title
Engineering acetyl coenzyme A supply: functional expression of a bacterial pyruvate dehydrogenase complex in the cytosol of Saccharomyces cerevisiae.
Sample Metadata Fields
Cell line, Subject
View Samples- Homo sapiens, Saccharomyces cerevisiae
- 2 Downloadable Samples
- Illumina HumanHT-12 V4.0 expression beadchip
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
The deafness gene DFNA5 induces programmed cell death through mitochondria and MAPK-related pathways.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 14 Downloadable Samples
- Affymetrix Human Genome U219 Array (hgu219)
Description
Adult-derived human liver stem/progenitor cells (ADHLSC) are obtained after primary culture of the liver parenchymal fraction. The cells are of fibroblastic morphology and exhibit a hepato-mesenchymal phenotype. Hepatic stellate cells (HSC) derived from the liver non-parenchymal fraction present a comparable morphology as ADHLSC. Because both ADHLSC and HSC are described as liver stem/progenitor cells, we strived to extensively compare both cell populations at different levels and to propose tools demonstrating their singularity.
Publication Title
Gene expression profiling and secretome analysis differentiate adult-derived human liver stem/progenitor cells and human hepatic stellate cells.
Sample Metadata Fields
Specimen part
View Samples- Saccharomyces cerevisiae
- 8 Downloadable Samples
- Affymetrix Yeast Genome S98 Array (ygs98)
Description
Metabolic fluxes may be regulated "hierarchically," e.g., by changes of gene expression that adjust enzyme capacities (V(max)) and/or "metabolically" by interactions of enzymes with substrates, products, or allosteric effectors. In the present study, a method is developed to dissect the hierarchical regulation into contributions by transcription, translation, protein degradation, and posttranslational modification. The method was applied to the regulation of fluxes through individual glycolytic enzymes when the yeast Saccharomyces cerevisiae was confronted with the absence of oxygen and the presence of benzoic acid depleting its ATP. Metabolic regulation largely contributed to the approximately 10-fold change in flux through the glycolytic enzymes. This contribution varied from 50 to 80%, depending on the glycolytic step and the cultivation condition tested. Within the 50-20% hierarchical regulation of fluxes, transcription played a minor role, whereas regulation of protein synthesis or degradation was the most important. These also contributed to 75-100% of the regulation of protein levels.
Publication Title
The fluxes through glycolytic enzymes in Saccharomyces cerevisiae are predominantly regulated at posttranscriptional levels.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 23 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Most cancer deaths are caused by metastases, which are the end-results of circulating tumor cells (CTC) that detach from the cancer primary and succeed to survive in distant organs. The aim of the present study was to develop a gene signature of CTC and to assess its prognostic relevance after surgery for pancreatic ductaladenocarcinoma (PDAC).
Publication Title
Pancreatic cancer circulating tumour cells express a cell motility gene signature that predicts survival after surgery.
Sample Metadata Fields
Sex, Age, Disease stage
View Samples- Homo sapiens
- 22 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Purpose: To explore the side population (SP) in pancreatic ductal adenocarcinoma (PDAC) for its gene expression profile and its association to cancer stem cells (CSC) and to evaluate the value of genes from its gene signature on patient survival.
Publication Title
Human pancreatic cancer contains a side population expressing cancer stem cell-associated and prognostic genes.
Sample Metadata Fields
Sex, Age, Specimen part, Disease stage
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U219 Array (hgu219)
Description
Primary Myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by hyperplastic megakaryopoiesis and myelofibrosis. Through a gene expression profile (GEP) study we recently highlighted the upregulationof miR-34a-5p in PMF versus healthy donor (HD) CD34+ hematopoietic progenitor cells (HPCs). To shed some light into the role of miR-34a-5p in PMF pathogenesis, here we unravelled the effects of the overexpression of miR-34a-5p in HPCs forcing its expression in HPCs.
Publication Title
Role of miR-34a-5p in Hematopoietic Progenitor Cells Proliferation and Fate Decision: Novel Insights into the Pathogenesis of Primary Myelofibrosis.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U219 Array (hgu219)
Description
As recently reported by our group, we performed miRNA and gene expression profiling of CD34+ hematopoietic stem/progenitor cells (HSPCs) isolated from 42 PMF patient samples compared with 31 healthy controls. Integrative analysis of these profiles by means of Ingenuity Pathway Analysis (IPA) allowed the identification of several aberrantly regulated miRNA-mRNA target pairs organized in interaction networks. In particular, our results highlighted the up-regulation of miR-494-3p in CD34+ cells from PMF patients (Norfo R et al, Blood, 2014). Interestingly, among the most upregulated miRNAs, miR-494-3p emerges as being associated to the highest number of downregulated target mRNAs. In order to understand the biological role of miR-494-3p during the hematopoietic commitment and differentiation, we overexpressed this miRNA in cord blood (CB) derived-CD34+ cells. Cells were electroporated with either miR-494-3p miRNA mimic (mimic miR-494) or a negative control mimic (mimic Neg CTR). qRT-PCR confirmed miR-494-3p overexpression 24h and 4 days after transfection (RQ SEM, 512.60 137.37, p<.01, and 20.63 3.03, p<.01, respectively).
Publication Title
miR-494-3p overexpression promotes megakaryocytopoiesis in primary myelofibrosis hematopoietic stem/progenitor cells by targeting SOCS6.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 22 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
In this study we conducted transcriptomics analyses of: (i) liver samples from patients suffering from acetaminophen-induced acute liver failure (n=3) and from healthy livers (n=2) and (ii) hepatic cell systems exposed to acetaminophen, including their respective vehicle controls. The investigated in vitro systems are: HepaRG cells, HepG2 cells and a novel human skinpostnatal stem cell-derived model i.e. human skin-precursors-derived hepatocyte-like cells (hSKP-HPC).
Publication Title
Gene expression data from acetaminophen-induced toxicity in human hepatic <i>in vitro</i> systems and clinical liver samples.
Sample Metadata Fields
Specimen part, Disease stage, Cell line
View Samples