Crystal cells are one of the 3 Drosophila blood cell lineages and represent less than 5% of the total hemocytes in wild type larvae. There development is notably controlled by mlf (myeloid leukemia factor), which regulate their number by stabilising the lineage-specific transcription factor Lozenge. To gain insight into the biology of this blood cell lineage and its regulation by mlf, we established the gene expression profile of the circulating crystal cells in wildtype and mlf mutant third instar larvae. This study provides a rich source of information to further characterise crystal cell function and regulation. In addition our data show that mlf is a major regulator of crystal cell gene expression programm and that mlf mutation leads to the accumulation of misdifferentiated crystal cells. Overall design: RNA expression profiles of sorted lz-GAL4,UAS-GFP+ circulating blood cells from wild type and mlf-/- third instar Drosophila larvae were generated by deep sequencing, in triplicate, using Illumina HiSeq2500 sequencing platform.
Control of RUNX-induced repression of Notch signaling by MLF and its partner DnaJ-1 during Drosophila hematopoiesis.
Specimen part, Subject
View SamplesHuman intervention study with two doses of iron (as ferrous gluconate via intestinal perfusion) to study the effect on genome-wide gene expression in the small intestine, in order to obtain detailed information about intestinal transcriptomics in vivo.
Gene expression in human small intestinal mucosa in vivo is mediated by iron-induced oxidative stress.
Sex, Disease, Disease stage, Subject
View SamplesWe report the differential gene expression differences between control and Ovol2-deficent newborn keratinocytes Overall design: Two control and two Ovol2-deficent samples were isolated
An Ovol2-Zeb1 transcriptional circuit regulates epithelial directional migration and proliferation.
Specimen part, Subject
View SamplesConsumption of resistant starch (RS) has been associated with various intestinal health benefits, but knowledge on its effects on global gene expression in the colon is limited. The main objective of the current study was to identify genes affected by RS in the proximal colon to infer which biologic pathways were modulated. Ten 17-wk-old male pigs, fitted with a cannula in the proximal colon for repeated collection of tissue biopsy samples and luminal content, were fed a digestible starch (DS) diet or a diet high in RS (34%) for 2 consecutive periods of 14 d in a crossover design. Analysis of the colonic transcriptome profiles revealed that, upon RS feeding, oxidative metabolic pathways, such as the tricarboxylic acid cycle and -oxidation, were induced, whereas many immune response pathways, including adaptive and innate immune system, as well as cell division were suppressed. The nuclear receptor peroxisome proliferator-activated receptor (PPARG) was identified as a potential key upstream regulator. RS significantly (P < 0.05) increased the relative abundance of several butyrate-producing microbial groups, including the butyrate producers Faecalibacterium prausnitzii and Megasphaera elsdenii, and reduced the abundance of potentially pathogenic members of the genus Leptospira and the phylum Proteobacteria. Concentrations in carotid plasma of the 3 main short-chain fatty acids acetate, propionate, and butyrate were significantly higher with RS consumption compared with DS consumption. Overall, this study provides novel insights on effects of RS in proximal colon and contributes to our understanding of a healthy diet.
Resistant starch induces catabolic but suppresses immune and cell division pathways and changes the microbiome in the proximal colon of male pigs.
Sex, Age, Specimen part
View SamplesBromodomain and extra terminal domain (BET) inhibition reduces occupancy of BET-family proteins at promoter and enhancer sites resulting in changes in the transcription of specific genes.
Inhibition of BET bromodomain-dependent XIAP and FLIP expression sensitizes KRAS-mutated NSCLC to pro-apoptotic agents.
Specimen part, Cell line
View SamplesBackground Small colony variants (SCVs) are slow-growing bacteria, which often show increased resistance to antibiotics and cause latent or recurrent infections. It is therefore important to understand the mechanisms at the basis of this phenotypic switch. Methodology/Principal findings One SCV (termed PAO-SCV) was isolated, showing high resistance to gentamicin and to the cephalosporine cefotaxime. PAO-SCV was prone to reversion as evidenced by emergence of large colonies with a frequency of 10-5 on media without antibiotics while it was stably maintained in presence of gentamicin. PAO-SCV showed a delayed growth, defective motility, and strongly reduced levels of the quorum sensing Pseudomonas quinolone signal (PQS). Whole genome expression analysis further suggested a multi-layered antibiotic resistance mechanism, including simultaneous over-expression of two drug efflux pumps (MexAB-OprM, MexXY-OprM), the LPS modification operon arnBCADTEF, and the PhoP-PhoQ two-component system. Conversely, the genes for the synthesis of PQS were strongly down-regulated in PAOSCV. Finally, genomic analysis revealed the presence of mutations in phoP and phoQ genes as well as in the mexZ gene encoding a repressor of the mexXY and mexABoprM genes. Only one mutation occurred only in REV, at nucleotide 1020 of the tufA gene, a paralog of tufB, both encoding the elongation factor Tu, causing a change of the rarely used aspartic acid codon GAU to the more common GAC, possibly causing an increase of tufA mRNA translation. High expression of phoP and phoQ was confirmed for the SCV variant while the revertant showed expression levels reduced to wild-type levels. Conclusions By combining data coming from phenotypic, gene expression and proteome analysis, we could demonstrate that resistance to aminoglycosides in one SCV mutant is multifactorial including overexpression of efflux mechanisms, LPS modification and is accompanied by a drastic down-regulation of the Pseudomonas quinolone signal quorum sensing system.
Phenotypic and genome-wide analysis of an antibiotic-resistant small colony variant (SCV) of Pseudomonas aeruginosa.
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View SamplesAngiopoietin-like protein 4 (ANGPTL4, also referred to as Fiaf) has been proposed as circulating mediator between the gut microbiota and fat storage in adipose tissue. Very little is known about mechanisms of regulation of ANGPTL4 in the colon. Here we show that transcription and subsequent secretion of ANGPTL4 in human T84 and HT-29 colonocytes is highly induced by physiological concentrations of products of bacterial fermentation, the short chain fatty acids (SCFA). Induction of ANGPTL4 by SCFA cannot be mimicked by the histone deacetylase inhibitor Trichostatin A. SCFA induce ANGPTL4 by activating the nuclear receptor PPAR, as shown by use of PPAR antagonist, PPAR knock-down, and transactivation assay, which shows activation of PPAR but not PPAR and PPAR. At concentrations required for PPAR activation and ANGPTL4 induction in colonocytes, SCFA do not stimulate PPAR in mouse 3T3-L1 and human SGBS adipocytes, suggesting that SCFA act as selective PPAR modulators (SPPARM), which is supported by coactivator peptide recruitment assay and structural modelling. Consistent with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin was associated with induction of PPAR target genes and pathways in the colon, as shown by microarray and subsequent gene set enrichment analysis. It can be concluded that 1) SCFA potently stimulate ANGPTL4 synthesis in human colonocytes; 2) SCFA transactivate and bind to PPAR by serving as selective PPAR modulators. Our data point to activation of PPAR as a novel mechanism of gene regulation by SCFA in the colon.
Short-chain fatty acids stimulate angiopoietin-like 4 synthesis in human colon adenocarcinoma cells by activating peroxisome proliferator-activated receptor γ.
Sex, Age, Specimen part
View SamplesAngiopoietin-like protein 4 (ANGPTL4, also referred to as Fiaf) has been proposed as a circulating mediator between the gut microbiota and fat storage in adipose tissue. Very little is known about the mechanisms of regulation of ANGPTL4 in the colon. Here we show that transcription and subsequent secretion of ANGPTL4 in human T84 and HT-29 colonocytes is highly induced by physiological concentrations of products of bacterial fermentation, the short-chain fatty acids. Short-chain fatty acids induce ANGPTL4 by activating the nuclear receptor PPAR, as shown by microarray, transactivation assays, coactivator peptide recruitment assay, and use of PPAR antagonist. At concentrations required for PPAR activation and ANGPTL4 induction in colonocytes, SCFA do not stimulate PPAR in mouse 3T3-L1 and human SGBS adipocytes, suggesting that SCFA act as selective PPAR modulators (SPPARM), which is supported by coactivator peptide recruitment assay and structural modelling. It can be concluded that 1) SCFA potently stimulate ANGPTL4 synthesis in human colonocytes, and 2) SCFA transactivate and bind to PPAR by serving as selective PPAR modulators. Our data point to activation of PPAR as a novel mechanism of gene regulation by SCFA in the colon.
Short-chain fatty acids stimulate angiopoietin-like 4 synthesis in human colon adenocarcinoma cells by activating peroxisome proliferator-activated receptor γ.
Specimen part, Cell line, Treatment
View SamplesCaenorhabditis elegans is a major eukaryotic experimental system employed to unravel a broad range of cellular and biological processes. Despite the many advantages of C. elegans, biochemical approaches to study tissue-specific gene expression in postembryonic stages are challenging. Here we report a novel experimental approach that enables the efficient determination of tissue-enriched transcriptomes by rapidly releasing nuclei from major tissues of postembryonic animals followed by fluorescence-activated nuclei sorting (FANS). Furthermore, we developed and applied a deep sequencing method, named 3'end-seq, which is designed to examine gene expression and identify 3' ends of transcripts using a small quantity of input RNA. In agreement with intestinal specific gene expression, promoter elements of highly expressed genes are enriched for GATA elements and their functional properties are associated with processes that are characteristic for the intestine. In addition, we systematically mapped pre-mRNA cleavage and polyadenylation sites, or polyA sites, including >3,000 sites that have previously not been identified. The analysis of nuclear mRNA revealed widespread alternative polyA site use in intestinally expressed genes. We describe several novel approaches that will be of significance to the analysis of tissue specific gene expression using small quantity RNA samples from C. elegans and beyond. Overall design: 3'end-seq of transcriptomes for input and sorted nuclei
Analysis of C. elegans intestinal gene expression and polyadenylation by fluorescence-activated nuclei sorting and 3'-end-seq.
Specimen part, Cell line, Subject
View SamplesWe used transgenic mouse embryos that are deficient in the two enzymatically active RNA editing enzymes ADAR1 and ADAR2 to compare relative frequencies but also sequence composition of mature miRNAs in these genetically modified backgrounds to wild-type mice by Illumina next gen sequencing. Deficiency of ADAR2 leads to a reproducible change in abundance of specific miRNAs and their predicted targets. Changes in miRNA abundance seem unrelated to editing events. Additional deletion of ADAR1 has surprisingly little impact on the mature miRNA repertoire, indicating that miRNA expression is primarily dependent on ADAR2. A to G transitions reflecting A to I editing events can be detected at few sites and at low frequency during the early embryonic stage investigated. Again, most editing events are ADAR2 dependent with only few editing sites being specifically edited by ADAR1. Besides known editing events in miRNAs a few novel, previously unknown editing events were identified. Some editing events are located to the seed region of miRNAs opening the possibility that editing leads to their retargeting. Overall design: GSM852140-8: sequencing of mature miRNAs of wt, ADAR2-/- and ADAR1-/-/ADAR2-/- female mouse embryos at E11.5 GSM863778-81: Gene expression was measured in wiltype, ADAR2-/- and ADAR1-/-/ADAR2-/- E11.5 whole female mouse embryos using Agilent Whole Mouse Genome Oligo Microarrays 8x60K.
Adenosine deaminases that act on RNA induce reproducible changes in abundance and sequence of embryonic miRNAs.
Sex, Specimen part, Cell line, Subject
View Samples