We hypothesized that broad-scale expression profiling would provide insight into the regulatory pathways that control gene expression in response to stress, and potentially identify novel heat-responsive genes. HEp2 cells were heated at 37 to 43 C for 60 min to gauge the heat shock response, using as a proxy inducible HSP-70 quantified by western blot analysis. Based on these results, microarray experiments were conducted at 37, 40, 41, 42 and 43C (3 replicates/temperature x 5 groups = 15 U95Aver2 GeneChips). Using linear modeling, we compared the sets of microarrays at 40, 41, 42 and 43C with the 37C baseline temperature and took the union of the genes exhibiting differential gene expression signal to create two sets of heat shock response genes, each set reflecting either increased or decreased RNA abundance. Leveraging human and mouse orthologous alignments, we used the two lists of co-expressed genes to predict transcription factor binding sites in silico, including those for heat shock factor 1 (HSF1) and heat shock factor 2 (HSF2) transcription factors. We discovered HSF1 and HSF2 binding sites in 15 genes not previously associated with the heat shock response. We conclude that microarray experiments coupled with upstream promoter analysis can be used to identify novel genes that respond to heat shock. Additional experiments are required to validate these putative heat shock proteins and facilitate a deeper understanding of the mechanisms involved during the stress response.
Transcriptional profiles of human epithelial cells in response to heat: computational evidence for novel heat shock proteins.
No sample metadata fields
View Samplesgene expression profiles of leukocytes from blood (WBCs) and spleen harvested at an early (two hours) time point after injury or sham injury in mice subjected to trauma-hemorrhage, burn injury or lipopolysaccharide (LPS)-infusion at three experimental sites
Commonality and differences in leukocyte gene expression patterns among three models of inflammation and injury.
No sample metadata fields
View SamplesMonitoring genome-wide, cell-specific responses to human disease, although challenging, holds great promise for medicines future. Patients with injury severe enough to develop multiple organ dysfunction syndrome (MODS) are known to have multiple immune derangements, including T-cell apoptosis and anergy combined with depressed monocyte antigen presentation. Genome-wide expression analysis of highly-enriched circulating leukocyte subpopulations, combined with cell-specific pathway analyses, offers a previously unavailable opportunity to discover novel leukocyte regulatory networks in critically injured patients. Severe injury induced significant changes in the T-cell, monocyte, and total leukocyte transcriptome, with only 12% of these genomic changes common to all three cell populations. T-cell-specific pathway analyses identified increased gene expression of several novel inhibitory receptors (PD-1, CD152, NRP-1, Lag3), and concomitant decreases in stimulatory receptors (CD28, CD4, IL-2Ralpha). Functional analysis of T-cells and monocytes confirmed reduced T-cell proliferation and increased cell surface expression of negative signaling receptors paired with decreased monocyte costimulation ligands. Thus, genome-wide expression from highly-enriched cell populations combined with knowledge-based pathway analyses leads to the identification of novel regulatory networks differentially expressed in injured patients. Importantly, application of cell separation, genome-wide expression, and cell specific pathway analyses can be used to discover novel pathway alterations in human disease.
Cell-specific expression and pathway analyses reveal alterations in trauma-related human T cell and monocyte pathways.
No sample metadata fields
View SamplesPurpose: The ability to rationally manipulate the transcriptional states of cells would be of great use in medicine and bioengineering. We have developed a novel algorithm, NetSurgeon, which utilizes genome-wide gene regulatory networks to identify interventions that force a cell toward a desired expression state. Results: We used NetSurgeon to select transcription factor deletions aimed at improving ethanol production in S. cerevisiae cultures that are catabolizing xylose. We reasoned that interventions that move the transcriptional states of cells utilizing xylose toward the fermentative state typical of cells that are producing ethanol rapidly (while utilizing glucose) might improve xylose fermentation. Some of the interventions selected by NetSurgeon successfully promoted a fermentative transcriptional state in the absence of glucose, resulting in strains with a 2.7-fold increase in xylose import rates, a 4-fold improvement in xylose integration into central carbon metabolism, or a 1.3-fold increase in ethanol production rate. Conclusions: We conclude by presenting an integrated model of transcriptional regulation and metabolic flux that will enable future metabolic engineering efforts aimed at improving xylose fermentation to prioritize functional regulators of central carbon metabolism. Overall design: Mutant and wildtype S. cerevisiae cells were put into 48 hour aerobic batch fermentations of synthetic complete medium supplmented with 2% glucose and 5% xylose and culture samples were taken at 4 hours and 24 hours for transcriptional profiling performed by RNA-Seq analysis. In addition, wildtype S. cerevisiae cells were grown in various single carbon sources for 12 hours and culture samples were taken for transcriptional profiling performed by RNA-Seq analysis.
Model-based transcriptome engineering promotes a fermentative transcriptional state in yeast.
Subject
View SamplesWe report here the genes that are sequentially expressed in white blood cells from blood and spleen at 2 hours, 2 day,3 days, and 7 days after burn and sham injury or trauma-hemorrhage (T-H) and sham T-H. Includes WBC treated with LPS for 2 hours and 1 day.
Comparison of longitudinal leukocyte gene expression after burn injury or trauma-hemorrhage in mice.
Specimen part, Treatment, Time
View SamplesOligonucleotide and complementary DNA microarrays are being used to subclassify histologically similar tumours, monitor disease progress, and individualize treatment regimens. However, extracting new biological insight from high-throughput genomic studies of human diseases is a challenge, limited by difficulties in recognizing and evaluating relevant biological processes from huge quantities of experimental data. Here we present a structured network knowledge-base approach to analyse genome-wide transcriptional responses in the context of known functional interrelationships among proteins, small molecules and phenotypes. This approach was used to analyse changes in blood leukocyte gene expression patterns in human subjects receiving an inflammatory stimulus (bacterial endotoxin). We explore the known genome-wide interaction network to identify significant functional modules perturbed in response to this stimulus. Our analysis reveals that the human blood leukocyte response to acute systemic inflammation includes the transient dysregulation of leukocyte bioenergetics and modulation of translational machinery. These findings provide insight into the regulation of global leukocyte activities as they relate to innate immune system tolerance and increased susceptibility to infection in humans.
A network-based analysis of systemic inflammation in humans.
No sample metadata fields
View SamplesPurpose: To compare the transcriptome profiles (RNA-seq) of cultured human epididymis cells and tissue from the caput, corpus and cauda regions of the human epididymis. Methods: Human epididymis tissue was obtained with Institutional Review Board approval from 3 patients (UC05, UC06, UC09, range: 22 - 36 years) undergoing inguinal radical orchiectomy for a clinical diagnosis of testicular cancer. None of the epididymides had extension of the testicular cancer. The three anatomical regions: caput, corpus and cauda, were separated and segments of each snap frozen. Adult human epididymis epithelial (HEE) cultures were also established from tissue. RNA was extracted from both tissue and cultured HEE cells and RNA-seq libraries prepared (TruSeq RNA Sample Preparation Kit v2, Low-Throughput protocol, Illumina). Libraries were sequenced on Illumina HiSeq2500 machines. Data were analyzed using TopHat and Cufflinks. Results: Libraries generated ~19-39 million reads per library from the cells (95-99% mapping to the human genome) and ~14-39 million reads from the tissue samples (84-99% mapped). Raw reads were aligned to the genome with Tophat and gene expression values were processed using Cufflinks as Fragments Per Kilobase per Million mapped fragments (FPKM). FPKM values were subject to principle component analysis, which revealed that though caput, corpus and cauda cell samples respectively from UC05, UC06 and UC09 clustered together. RNA-seq data from the 3 biological replicas (UC05, UC06 and UC09) of caput, corpus and cauda were pooled for further analysis. Cufflinks was used to determine differentially expressed genes (DEGs) between caput, corpus and cauda cells, combined from the 3 donors. The gene expression profiles of corpus and cauda are remarkably similar and both differ from the caput to a similar degree. We identified ~40 genes differentially expressed between corpus and cauda and more than 1600 DEGs between caput and cauda. The DEGs for each comparison (caput and corpus/cauda) were analysed using a gene ontology process enrichment analysis (DAVID, Huang et al., NAR 2009;37:1-13, Huang et al., 2009 Nat Prot 4:44-57). Conclusions: Here we describe an in depth analysis of the gene expression repertoire of primary cultures of epithelial cells and intact tissues from each region of the adult human epididymis. These data will be valuable to decipher pathways of normal epididymis function and aspects of epididymis disease that cause male infertility. Overall design: RNA-seq was performed on libraries generated from caput, corpus and cauda-derived cultured cells (passage 2 or 3) from 3 donors and on caput, corpus and cauda tissue from 2 of the same donors. Donor age range: 22 - 36 years.
Expression profiles of human epididymis epithelial cells reveal the functional diversity of caput, corpus and cauda regions.
No sample metadata fields
View SamplesMYB-bHLH-TTG1 regulates Arabidopsis seed coat biosynthesis pathways directly and indirectly via multiple tiers of transcription factors
MYB-bHLH-TTG1 Regulates Arabidopsis Seed Coat Biosynthesis Pathways Directly and Indirectly via Multiple Tiers of Transcription Factors.
Specimen part
View SamplesHNF1a and HNF1ß recognize the same DNA consensus sequence in the genome, to which they bind as homodimers or heterodimers. Both factors share a high degree of homology their DNA binding and dimerization (N-terminus) regions but have a more divergent C-terminal transactivation domain. HNF1ß is essential for the generation of a functional male reproductive tract in mice and genital tract abnormalities are evident in humans with recessive mutations in HNF1ß. The functions of HNF1a and HNF1ß have been studied in epithelia from other several tissues (liver, kidney, intestine, and pancreas) but their role in the adult human epididymis epithelium (HEE) remains unexplored. We established that HNF1a/ß are expressed in caput HEE cells and are predicted to occupy cis-regulatory elements in these cells. To investigate the contribution of HNF1 in controlling gene expression in caput cells we performed siRNA-mediated depletion of HNF1a and HNF1ß together, followed by RNA-seq analysis. Three replicas of caput cells were transfected with the specific siRNAs or with a non-targeting control siRNA. RNA-seq after HNF1 depletion showed significant alterations in the expression of genes encoding ion channels and exchangers that are involved in controlling the luminal environment in the caput epididymis. Overall design: mRNA profiles from Caput HEE cells transfected with negative control (NC) or HNF1alpha and HNF1beta siRNA, in triplicate.
HNF1 regulates critical processes in the human epididymis epithelium.
No sample metadata fields
View SamplesPhysiological, anatomical, and clinical laboratory analytic scoring systems (APACHE, Injury Severity Score (ISS)) have been utilized, with limited success, to predict outcome following injury. We hypothesized that a peripheral blood leukocyte gene expression score could predict outcome, including multiple organ failure, following severe blunt trauma.
A genomic score prognostic of outcome in trauma patients.
Sex, Age
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