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Saccharomyces cerevisiae
16 Downloadable Samples
Affymetrix Yeast Genome S98 Array (ygs98)
Description
Saccharomyces cerevisiae has become a popular host for production of non-native compounds. The metabolic pathways involved generally require a net input of energy. To maximize the ATP yield on sugar in S. cerevisiae, industrial cultivation is typically performed in aerobic, sugar-limited fed-batch reactors which, due to constraints in oxygen transfer and cooling capacities, have to be operated at low specific growth rates. Because intracellular levels of key metabolites and cellular energy status are growth-rate dependent, slow growth can significantly affect biomass-specific productivity. Using an engineered Saccharomyces cerevisiae strain expressing a heterologous pathway for resveratrol production as a model energy-requiring product, the impact of specific growth rate on yeast physiology and productivity was investigated in aerobic, glucose-limited chemostat cultures.
Publication Title
Growth-rate dependency of de novo resveratrol production in chemostat cultures of an engineered Saccharomyces cerevisiae strain.
Sample Metadata Fields
No sample metadata fields
View Samples- Saccharomyces cerevisiae
- 12 Downloadable Samples
- Affymetrix Yeast Genome S98 Array (ygs98)
Description
In contrast to batch cultivation, chemostat cultivation allows the identification of carbon source responses without interference by carbon-catabolite repression, accumulation of toxic products, and differences in specific growth rate. This study focuses on the yeast Saccharomyces cerevisiae, grown in aerobic, carbon-limited chemostat cultures. Genome-wide transcript levels and in vivo fluxes were compared for growth on two sugars, glucose and maltose, and for two C2-compounds, ethanol and acetate. In contrast to previous reports on batch cultures, few genes (180 genes) responded to changes of the carbon source by a changed transcript level. Very few transcript levels were changed when glucose as the growth-limiting nutrient was compared with maltose (33 transcripts), or when acetate was compared with ethanol (16 transcripts). Although metabolic flux analysis using a stoichiometric model revealed major changes in the central carbon metabolism, only 117 genes exhibited a significantly different transcript level when sugars and C2-compounds were provided as the growthlimiting nutrient. Despite the extensive knowledge on carbon source regulation in yeast, many of the carbon source-responsive genes encoded proteins with unknown or incompletely characterized biological functions. In silico promoter analysis of carbon source-responsive genes confirmed the involvement of several known transcriptional regulators and suggested the involvement of additional regulators. Transcripts involved in the glyoxylate cycle and gluconeogenesis showed a good correlation with in vivo fluxes. This correlation was, however, not observed for other important pathways, including the pentose-phosphate pathway, tricarboxylic acid cycle, and, in particular, glycolysis. These results indicate that in vivo fluxes in the central carbon metabolism of S. cerevisiae grown in steadystate, carbon-limited chemostat cultures are controlled to a large extent via post-transcriptional mechanisms.
Publication Title
Role of transcriptional regulation in controlling fluxes in central carbon metabolism of Saccharomyces cerevisiae. A chemostat culture study.
Sample Metadata Fields
No sample metadata fields
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
- 105 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Parkinsons disease (PD) progresses relentlessly and affects five million people worldwide. Laboratory tests for PD are critically needed for developing treatments designed to slow or prevent progression of the disease. We performed a transcriptome-wide scan in 105 individuals to interrogate the molecular processes perturbed in cellular blood of patients with early-stage PD. The molecular marker here identified is strongly associated with risk of PD in 66 samples of the training set (third tertile cross-validated odds ratio of 5.7 {P for trend 0.005}). It is further validated in 39 independent test samples (third tertile odds ratio of 5.1 {P for trend 0.04}). The genes differentially expressed in patients with PD, or Alzheimers or progressive supranuclear palsy offer unique insights into disease-linked processes detectable in peripheral blood. Combining gene expression scans in blood and linked clinical data will facilitate the rapid characterization of candidate biomarkers as demonstrated here with respect to PD.
Publication Title
Molecular markers of early Parkinson's disease based on gene expression in blood.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 30 Downloadable Samples
IlluminaHiSeq2000
Description
Prostate cancer is the most commonly diagnosed and second-most lethal cancer among men in the United States. The vast majority of prostate cancer deaths are due to castration-resistant prostate cancer (CRPC) – the lethal form of the disease that has progressed despite therapies that interfere with activation of androgen receptor (AR) signaling. One emergent resistance mechanism to medical castration is synthesis of intratumoral androgens that activate the AR. This insight led to the development of the AR antagonist enzalutamide. However, resistance to enzalutamide invariably develops, and disease progression is nearly universal. One mechanism of resistance to enzalutamide is an F877L mutation in the AR ligand-binding domain that can convert enzalutamide to an agonist of AR activity. However, mechanisms that contribute to the agonist switch had not been fully clarified, and there were no therapies to block AR F877L. Using cell line models of castration-resistant prostate cancer (CRPC), we determined that cellular androgen content influences enzalutamide agonism of mutant F877L AR. Further, enzalutamide treatment of AR F877L-expressing cell lines recapitulated the effects of androgen activation of F877L AR or wild-type AR. Because the BET bromodomain inhibitor JQ-1 was previously shown to block androgen activation of wild-type AR, we tested JQ-1 in AR F877L-expressing CRPC models. We determined that JQ-1 suppressed androgen or enzalutamide activation of mutant F877L AR and suppressed growth of mutant F877L AR CRPC tumors in vivo, demonstrating a new strategy to treat tumors harboring this mutation. Overall design: RNA-seq profiles of prostate cancer cell lines to understand gene expression associated with enzalutamide treatment
Publication Title
Cellular androgen content influences enzalutamide agonism of F877L mutant androgen receptor.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 8 Downloadable Samples
- NextSeq 500
Description
Mucosa-associated invariant T (MAIT) cells are unconventional innate-like T cells that recognize microbial riboflavin metabolites presented by the MHC class I-like protein MR1. Human MAIT cells predominantly express the CD8a co-receptor (CD8+), with a smaller subset lacking both CD4 and CD8 (DN). However, it is unclear if these two MAIT cell sub-populations distinguished by CD8a represent functionally distinct subsets. To address this, we investigated the phenotypic, transcriptional, and functional differences between CD8+ and DN MAIT cells using human samples from peripheral blood, mucosal tissues, and fetal tissues. Overall design: We FACS sorted CD8+ and CD8- MAIT cells from human peripheral blood and performed bulk RNAseq on these cells
Publication Title
The CD4<sup>-</sup>CD8<sup>-</sup> MAIT cell subpopulation is a functionally distinct subset developmentally related to the main CD8<sup>+</sup> MAIT cell pool.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 7 Downloadable Samples
- Affymetrix Human Gene 2.0 ST Array (hugene20st)
Description
Computational identification of gene expression pathways in cysts alongside tubular organoids
Publication Title
Organoid cystogenesis reveals a critical role of microenvironment in human polycystic kidney disease.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 44 Downloadable Samples
- Illumina HiSeq 4000
Description
Adipocytes arise from commitment and differentiation of adipose precursors in white adipose tissue (WAT). In studying adipogenesis, precursor markers, including Pref-1 and PDGFRa, are used to isolate precursors from stromal vascular fraction of WAT, but the relationship among the markers is not known. Here, we used Pref-1 promoter-rtTA system in mice for labeling Pref-1+ cells and for inducible inactivation of Pref-1 target, Sox9. We show requirement of Sox9 for maintenance of Pref-1+ proliferative, early precursors. Upon Sox9 inactivation, these Pref-1+ cells become PDGFRa+ cells that express early adipogenic markers. Thus, we show for the first time that Pref-1+ cells precede PDGFRa+ cells in the adipogenic pathway and that Sox9 inactivation is required for WAT growth and expansion. Furthermore, we show that, in maintaining early adipose precursors, Sox9 activates Meis1 which prevents adipogenic differentiation. Our study also demonstrates the Pref-1 promoter-rtTA system for inducible gene inactivation in early adipose precursor population. Overall design: RNA-Sequencing for differentially expressed genes (more than 2-fold) between GFP+ (Pref-1+) ingWAT SVF cells from floxed and Sox9 PreASKO mice (n=6 pooled).
Publication Title
Sox9-Meis1 Inactivation Is Required for Adipogenesis, Advancing Pref-1<sup>+</sup> to PDGFRα<sup>+</sup> Cells.
Sample Metadata Fields
Sex, Age, Specimen part, Subject
View Samples- Mus musculus
- 2 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Sox9-Meis1 Inactivation Is Required for Adipogenesis, Advancing Pref-1<sup>+</sup> to PDGFRα<sup>+</sup> Cells.
Sample Metadata Fields
Sex, Age, Specimen part, Cell line
View Samples
GSE14566- Homo sapiens
- 2 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Nucleotides triphosphates are extracellular messengers binding to specific plasma membrane receptors (P2Rs) that modulate responses as different as proliferation, differentiation, migration or cell death on several cell types including hematopoietic stem cells. Little and controversial information is available on the role of extracellular nucleotides in human mesenchimal stem cells (hMSCs). In this study, we assessed whether P2Rs are expressed and functional in bone marrow-derived hMSCs. Our results demonstrated, at the mRNA and protein level, the expression of all P2X and P2Y receptor subtypes identified so far. P2R activation by their natural ligands adenosine triphosphate (ATP) and uridine triphosphate (UTP) induced in hMSCs, intracellular Ca2+ concentration changes, plasma membrane depolarization and permeabilization. hMSCs were resistant to the cytotoxic effects of high dose ATP despite the expression of permeabilizing P2Rs as demonstrated by the lack of morphological changes, significant release of intracellular markers of cell death or modification of the mitochondrial network. Gene expression profiling revealed the down-regulation of cell proliferation genes whereas genes involved in cell migration and cytokine production were strongly up-regulated by ATP. Functional studies confirmed the inhibitory activity of ATP on proliferation of hMSCs and clonogenic progenitors. Moreover, ATP exerted a chemotactic effect on hMSCs and increased their migration in response to the chemokine CXCL12. Finally, whereas ATP did not affect T-cell inhibitory activity of hMSCs, the nucleotide increased the production of pro-inflammatory cytokines by hMSCs. Thus, our data show that purinergic signaling modulates hMSC functions and point to a role for extracellular nucleotides on hMSCs biology.
Publication Title
Purinergic stimulation of human mesenchymal stem cells potentiates their chemotactic response to CXCL12 and increases the homing capacity and production of proinflammatory cytokines.
Sample Metadata Fields
No sample metadata fields
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