Metazoans utilize a handful of highly conserved signaling pathways to create a signaling backbone that governs all stages of development, by providing spatial and temporal cues that influence gene expression. How these few signals have such a versatile developmental action is of significance to evolution, development, and disease. Their versatility likely depends upon the larger-scale network they form through integration. Such integration is exemplified by cross-talk between the Notch and the Receptor Tyrosine Kinase (RTK) pathways. We examined the transcriptional output of Notch-RTK cross-talk during Drosophila development and present in vivo data that supports a role for selected mutually-regulated genes as potentially important nodal points for signal integration. We find the complex interplay between these pathways involves their mutual regulation of numerous core components of RTK signaling in addition to targets that include components of all the major signalling pathways (TGF-, Hh, Jak/Stat, Nuclear Receptor and Wnt). Interestingly, Notch-RTK integration did not lead to general antagonism of either pathway, as is commonly believed. Instead, integration had a combinatorial effect on specific cross-regulated targets, which unexpectedly included the majority of Ras-responsive genes, suggesting Notch can specify the response to Ras activation.
Nodal points and complexity of Notch-Ras signal integration.
No sample metadata fields
View Samples5 day RNAi treatment to knockdown Enigma, CG9006, a Drosophila mitochondrial protein with homology to acyl-CoA dehydrogenases.
Enigma, a mitochondrial protein affecting lifespan and oxidative stress response in Drosophila.
No sample metadata fields
View SamplesThe goal of this study was to determine how decreased mitochondrial citrate export influences gene expression in Drosophila larvae. RNA was isolated from Drosopohila sea mutants, which exhibiti decreased mitochondrial citrate transport activity, and a genetically-matched control strain during mid-L3 development. Overall design: Larvae were collected as described in Li, H., Tennessen, J. M. Preparation of Drosophila Larval Samples for Gas Chromatography-Mass Spectrometry (GC-MS)-based Metabolomics. J. Vis. Exp. (136), e57847, doi:10.3791/57847 (2018). RNA was purified from staged mid-L3 larvae using a RNeasy Mini Kit (Qiagen). Sequencing was performed using an Illumina NextSeq500 platform with 75 bp sequencing module generating 41 bp paired-end reads. After the sequencing run, demultiplexing was performed with bcl2fastq v2.20.0.422.
A <i>Drosophila</i> model of combined D-2- and L-2-hydroxyglutaric aciduria reveals a mechanism linking mitochondrial citrate export with oncometabolite accumulation.
Subject
View SamplesA fermentation strategies with phosphate feeding was applied to elongate transition inti phosphate limitation for an tryptophan overproducing E. coli strain
Phosphate limited fed-batch processes: impact on carbon usage and energy metabolism in Escherichia coli.
No sample metadata fields
View SamplesObstructive sleep apnea (OSA) has been linked to dysregulated metabolic states and treatment of sleep apnea may improve these conditions. Subcutaneous adipose tissue is a readily samplable fat depot that plays an important role in regulating metabolism. However, neither the pathophysiologic consequences of OSA nor the effects of continuous positive airway pressure (CPAP) in altering this compartment’s molecular pathways are understood. This study aimed to systematically identify subcutaneous adipose tissue transcriptional programs modulated in OSA and in response to its effective treatment with CPAP. Two subject groups were investigated: Study Group 1 was comprised of 10 OSA and 8 controls; Study Group 2 included 24 individuals with OSA studied at baseline and following CPAP. For each subject, genome-wide gene expression measurement of subcutaneous fat was performed. Differentially activated pathways elicited by OSA (Group 1) and in response to its treatment (Group 2) were determined using network and Gene Set Enrichment Analysis (GSEA). In Group 2, treatment of OSA with CPAP improved apnea hypopnea index, daytime sleepiness, and blood pressure, but not anthropometric measures. In Group 1, GSEA revealed many up-regulated gene sets in OSA subjects, most of which were involved in immuno-inflammatory (e.g., interferon-γ signaling), transcription, and metabolic processes such as adipogenesis. Unexpectedly, CPAP therapy in Group 2 subjects was also associated with up-regulation of several immune pathways as well as cholesterol biosynthesis. Collectively, our findings demonstrate that OSA alters distinct inflammatory and metabolic programs in subcutaneous fat, but these transcriptional signatures are not reversed with short-term effective therapy.
Obstructive sleep apnea and CPAP therapy alter distinct transcriptional programs in subcutaneous fat tissue.
Sex, Age
View SamplesSpheroids are 3D multi-cell aggregates formed in non-addherent culture conditions. In ovarian cancer (OC), they serve as a vehicle for cancer cell dissemination in the peritoneal cavity. We investigated genes and networks upregulated in three dimensional (3D) versus two-dimensional (2D) culture conditions by Affymetrix gene expression profiling and identified ALDH1A1, a cancer stem cell marker as being upregulated in OC spheroids. Network analysis confirmed ALDH1A1 upregulation in spheroids in direct connection with elements of the -catenin pathway. A parallel increase in the expression levels of -catenin and ALDH1A1 was demonstrated in spheroids vs. monolayers an in successive spheroid generations by using OC cell liness and primary OC cells. The percentage of Aldefluor positive cells was significantly higher in spheroids vs. monolayers in IGROV1, A2780, SKOV3, and primary OC cells. B-catenin knock-down decreased ALDH1A1 expression and chromatin immunoprecipitation demonstrated that -catenin directly binds to the ALDH1A1 promoter. Both siRNA mediated -catenin knock-down and a novel ALDH1A1 small molecule enzymatic inhibitor described here for the first time, decreased the number of OC spheroids (p<0.001) and cell viability. These data strongly support the role of -catenin regulated ALDH1A1 in the maintenance of OC spheroids and of a stem cell phenotype and propose new ALDH1A1 inhibitors targeting this cell population.
β-Catenin-regulated ALDH1A1 is a target in ovarian cancer spheroids.
Specimen part
View SamplesAffymetrix microarray data was generated from MCF7 breast cancer cells treated in vitro with siRNAs against 78 transcription factors and signalling molecules.
Cell cycle gene networks are associated with melanoma prognosis.
Cell line
View SamplesAffymetrix microarray data were generated from A375 melanoma cells treated in vitro with siRNAs against 45 transcription factors and signalling molecules.
Cell cycle gene networks are associated with melanoma prognosis.
Cell line
View SamplesIntragenic microRNAs (miRNAs), including both intronic and exonic miRNAs, accounting approximately 50% of total mammalian miRNAs. Previous studies showed that intragenic miRNAs are often co-expressed with their host genes, and thus it was believed that intragenic miRNAs and their host genes are derived from the same primary transcripts. However, we provide evidence to show here that the observations from previous studies might be biased due to the small number and the predominance of "broadly conserved" intronic miRNAs they studied.
Young intragenic miRNAs are less coexpressed with host genes than old ones: implications of miRNA-host gene coevolution.
Disease, Disease stage, Cell line
View SamplesGene expression signatures were measured in logarithmic growing cultures
Oncogenic BRAF regulates oxidative metabolism via PGC1α and MITF.
Specimen part
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