Using gene expression profiling we characterize the global effect of p53 on the TLR5-mediated transcription in MCF7 cells. We found that combined activation of p53 and TLR5 pathways synergistically increases expression of over 200 genes, mostly associated with immunity and inflammation. The synergy was observed in several human cancer cells and primary lymphocytes.
p53 amplifies Toll-like receptor 5 response in human primary and cancer cells through interaction with multiple signal transduction pathways.
Cell line
View SamplesDetermining mechanism-based biomarkers that distinguish adaptive and adverse cellular processes is critical to understanding the health effects of environmental exposures. Shifting from in vivo, low-throughput toxicity studies to high-throughput screening (HTS) paradigms and risk assessment based on in vitro and in silico testing requires utilizing toxicity pathway information to distinguish adverse outcomes from recoverable adaptive events. Little work has focused on oxidative stresses in human airway for the purposes of predicting adverse responses. We hypothesize that early gene expression-mediated molecular changes could be used to delineate adaptive and adverse responses to environmentally-based perturbations. Here, we examined cellular responses of the tracheobronchial airway to zinc (Zn) exposure, a model oxidant. Airway derived BEAS-2B cells exposed to 210 M Zn2+ elicited concentration- and time-dependent cytotoxicity. Normal, adaptive, and cytotoxic Zn2+ exposure conditions were determined with traditional apical endpoints, and differences in global gene expression around the tipping point of the responses were used to delineate underlying molecular mechanisms. Bioinformatic analyses of differentially expressed genes indicate early enrichment of stress signaling pathways, including those mediated by the transcription factors p53 and NRF2. After 4 h, 154 genes were differentially expressed (p <0.01) between the adaptive and cytotoxic Zn2+ concentrations. Nearly 40% of the biomarker genes were related to the p53 signaling pathway with 30 genes identified as likely direct targets using a database of p53 ChIP-seq studies. Despite similar p53 activation profiles, these data revealed widespread dampening of p53 and NRF2-related genes as early as 4 h after exposure at higher, unrecoverable Zn2+ exposures. Thus, in our model early increased activation of stress response pathways indicated a recoverable adaptive event. Overall, this study highlights the importance of characterizing molecular mechanisms around the tipping point of adverse responses to better inform HTS paradigms.
Developing a Gene Biomarker at the Tipping Point of Adaptive and Adverse Responses in Human Bronchial Epithelial Cells.
Cell line, Time
View SamplesInfectious laryngotracheitis (ILT) is an acute, contagious, upper respiratory disease, which is caused by gallid herpesvirus 1 (GaHV-1). Due to the mortality rates up to 70% depending on the virulence of the virus, it is of economic importance of the disease to explore the etiology of the ILT in the poultry industry. In this study, 15-day-old SPF white leghorn chickens were used to transcriptome analysis in chicken trachea immunized with infectious laryngotracheitis virus vaccine. In conclusion, chicken embryo origin (CEO) vaccine activation of the MHC-I and MHC-II pathways provides insight into the molecular mechanism of immune response in chickens, and holds potential for evaluation and design of new ILT vaccines in a manner adapted to the host immune response to the virus. Overall design: Ten vaccine inoculated birds were randomly divided in two groups. Each group represents one replication of five pooled tissues, for inoculated birds. Control group consists of five birds that received sterile vaccine diluent.
Transcriptome analysis reveals an activation of major histocompatibility complex 1 and 2 pathways in chicken trachea immunized with infectious laryngotracheitis virus vaccine.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Diverse stresses dramatically alter genome-wide p53 binding and transactivation landscape in human cancer cells.
Specimen part, Cell line, Treatment
View SamplesThe effects of diverse stresses on promoter selectivity and transcription regulation by the tumor suppressor p53 are poorly understood. We have taken a comprehensive approach to characterizing the human p53 network that includes p53 levels, binding, expression and chromatin changes under diverse stresses. Human osteosarcoma U2OS cells treated with anti-cancer drugs Doxorubicin or Nutlin-3 led to strikingly different p53 gene binding patterns based on ChIP-seq experiments. While two contiguous RRRCWWGYYY decamers is the consensus binding motif, p53 can bind a single decamer and function in vivo. Although the number of sites bound by p53 was 6-times greater for Nutlin-3 than Doxorubicin, expression changes induced by Nutlin-3 were much less dramatic compared to Doxorubicin. Unexpectedly, the solvent DMSO alone induced p53 binding to many sites common to Doxorubicin; however, this binding had no effect on target gene expression. Together, these data imply a two-stage mechanism for p53 transactivation where p53 binding only constitutes the first stage. Furthermore, both p53 binding and transactivation were associated with increased active histone modification H3K4me3. We discovered 149 putative new p53 target genes including several that are relevant to tumor suppression, revealing potential new targets for cancer therapy and expanding our understanding of the p53 regulatory network.
Diverse stresses dramatically alter genome-wide p53 binding and transactivation landscape in human cancer cells.
Specimen part, Cell line
View SamplesSince the first generation of induced Pluripotent Stem cells (iPSCs), several reprogramming systems have been used to study its molecular mechanisms. However, the system of choice largely affects the reprogramming efficiency, influencing our view on the mechanisms. Here we demonstrate that reprogramming triggered by less efficient polycistronic reprogramming cassettes not only highlights Mesenchymal-Epithelial Transition (MET) as a roadblock, but also faces more severe difficulties to attain a pluripotent state even post-MET. Also, in contrast to previous findings, more efficient cassettes can reprogram both wild type and Nanog-/- fibroblasts with comparable efficiencies, routes and kinetics, rebutting previous studies that Nanog is critical for iPSC generation. We revealed that the 9 amino acids in the N-terminus of Klf4 in polycistronic reprogramming cassettes are the dominant factor causing these critical differences. Our data establishes that some reprogramming roadblocks are system-dependent, highlighting the need to pursue mechanistic studies with close attention to the systems to better understand reprogramming. Overall design: The aim of the experiment is to compare the reprogramming pathways driven by two different polycistronic cassettes (MKOS and OKMS). We have isolated cells at intermediate stages of both MKOS and OKMS reprogramming and analysed their gene expression profiles. 2N- are CD44- ICAM1-, Nanog-GFP-, 3N- are CD44- ICAM1+, Nanog-GFP-, 3N+ are CD44- ICAM1+, Nanog-GFP+, all from day 10 of reprogramming. MKOS/OKMS iPSCs are established iPSC clones, TNG an Embryonic Stem Cell line carrying a Nanog-GFP reporter published in Chambers et al. Cell, 113, 643-655, from this line TNG MKOS and OKMS Embryonic Stem Cells were generated after targeting the Sp3 locus with the MKOS or the OKMS cassette respectively,E14 a reference Embryonic Stem Cell line and MEF are Mouse Embryonic Fibroblasts either wild type or generaterd from TNG MKOS or OKMS ESCs. D6 is the D6s4B5 iPSC line published in O''Malley et al. Nature, 499, 88-91.
Reprogramming Roadblocks Are System Dependent.
No sample metadata fields
View SamplesThe goal of the study is to identify p53 target genes specific to macrophages using the p53 stabilizer, Nutlin-3.
p53 and NF-κB coregulate proinflammatory gene responses in human macrophages.
Sex, Age, Specimen part, Disease, Treatment, Race, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Revealing a human p53 universe.
Specimen part, Subject
View SamplesGene expression analysis of the p53 response in PHA-stimulated human T-lymphocytes treated ex vivo with either Doxorubicin, Nutlin-3, or DMSO
Revealing a human p53 universe.
Specimen part, Subject
View SamplesWhile gene regulatory networks involved in cardiogenesis have been characterized, the role of bioenergetics remains less studied. Here we show that until midgestation, myocardial metabolism is compartmentalized, with a glycolytic signature restricted to compact myocardium contrasting with increased mitochondrial oxidative activity in the trabeculae. HIF1a regulation mirrors this pattern, with expression predominating in compact myocardium and scarce in trabeculae. By midgestation, the compact myocardium downregulates HIF1a and switches toward oxidative metabolism. Deletion of the E3 ubiquitin ligase Vhl results in HIF1a hyperactivation, disrupting metabolic compartmentalization and blocking the midgestational shift toward oxidative phosphorylation. Moreover, the altered glycolytic signature induced by HIF1 trabecular activation precludes regulation of genes essential for cardiac conduction system establishment. Our findings reveal VHL-HIF-mediated metabolic compartmentalization in the developing heart and the connection between metabolism and myocardial differentiation. These results highlight the importance of bioenergetics in ventricular myocardium specialization and its potential relevance to congenital heart disease. Overall design: RNA was isolated from individual E12.5 embryonic hearts after removal of the atria and valvular region. KOs and control littermates were matched by somite count, and a total number of 3 KOs and 3 controls from 3 independent litters were used. For RNA extraction, QIAzol Lysis Reagent (Qiagen; CA; USA) and the miRNeasy Mini Kit (Qiagen; CA; USA) were used. RNA was quantified and its purity checked with a NanoDrop ND-1000 spectophotometer (Thermo Scientific; MA; USA). RNA integrity was verified with an Agilent 2100 Bioanalyzer (Agilent Technologies; CA; USA). Index-tagged cDNA libraries were constructed from 500 ng of total RNA using the TruSeq RNA Sample Preparation v2 Kit (Illumina; CA; USA). Libraries were quantified by Quant-iTâ„¢ dsDNA HS assay in a Q-bit fluorometer (Life Technologies; CA; USA). Average library size and size distribution were determined by DNA 1000 assay in an Agilent 2100 Bioanalyzer. Libraries were normalized to 10nM using 10mM Tris-HCl, pH8.5 containing 0.1% Tween 20 and then applied to an Illumina flow cell for cluster generation (True Seq SR Cluster Kit V2 cBot) and sequencing-by-synthesis. Single reads of length 75bp were generated with the TruSeq SBS Kit v5 (Illumina; CA; USA) on the Genome Analyzer IIx platform, following the standard RNA sequencing protocol. Reads were further processed using the CASAVA package (Illumina; CA; USA) to split reads according to adapter indexes and produce fastq files.
Myocardial VHL-HIF Signaling Controls an Embryonic Metabolic Switch Essential for Cardiac Maturation.
Specimen part, Subject
View Samples