This SuperSeries is composed of the SubSeries listed below.
The effects of EBV transformation on gene expression levels and methylation profiles.
Sex, Specimen part, Subject
View SamplesEpstein-Barr virus (EBV) transformed lymphoblastoid cell lines (LCLs) are a widely used renewable resource for functional genomic studies in humans. The ability to accumulate multidimensional data pertaining to the same individual cell lines, from complete genomic sequences to detailed gene regulatory profiles, further enhances the utility of LCLs as a model system. However, the extent to which LCLs are a faithful model system is relatively unknown. We have previously shown that gene expression profiles of newly established LCLs maintain a strong individual component. Here, we extend our study to investigate the effect of freeze-thaw cycles on gene expression patterns in mature LCLs, especially in the context of inter-individual variation in gene regulation. We found a profound difference in the gene expression profiles of newly established and mature LCLs. Once newly established LCLs undergo a freeze-thaw cycle, the individual specific gene expression signatures become much less pronounced as the gene regulatory programs in LCLs from different individuals converge to a more uniform profile, which reflects a mature transformed B cell phenotype. As expected, previously identified eQTLs are enriched among the relatively few genes whose regulations in mature LCLs maintain marked individual signatures. We thus conclude that findings and insight drawn from gene regulatory studies in mature LCLs are generally not affected by artificial nature of the LCL model system and are likely to faithfully reflect regulatory interactions in primary tissues. However, our data indicate that many aspects of primary B cell biology cannot be observed and studied in mature LCL cultures.
The effect of freeze-thaw cycles on gene expression levels in lymphoblastoid cell lines.
Sex, Specimen part
View SamplesEpstein-Barr virus (EBV)-transformed lymphoblastoid cell lines (LCLs) provide a conveniently accessible and renewable resource for functional studies in humans. The ability to accumulate multidimensional data pertaining to the same individual cell lines, from complete genomic sequences to detailed gene regulatory profiles, further enhances the utility of LCLs as a model system. A lingering concern, however, is that the changes associated with EBV transformation of LCLs reduce the usefulness of LCLs as a surrogate model for primary tissues. To evaluate the validity of this concern, we compared global gene expression profiles between CD20+ primary B cells and CD3+ primary T cells sampled from six individuals. Six independent replicates of transformed LCLs were derived from each sample.
The effects of EBV transformation on gene expression levels and methylation profiles.
Sex, Specimen part, Subject
View SamplesTranscriptom analysis of microdissect adrenal medulla after 8 weeks of cardiac pressure overload caused by transverse aortic constriction.
Chronic cardiac pressure overload induces adrenal medulla hypertrophy and increased catecholamine synthesis.
Sex
View SamplesThe use of low quality RNA samples in whole-genome gene expression profiling remains controversial. It is unclear if transcript degradation in low quality RNA samples occurs uniformly, in which case the effects of degradation can be normalized, or whether different transcripts are degraded at different rates, potentially biasing measurements of expression levels. This concern has rendered the use of low quality RNA samples in whole-genome expression profiling problematic. Yet, low quality samples are at times the sole means of addressing specific questions – e.g., samples collected in the course of fieldwork.
RNA-seq: impact of RNA degradation on transcript quantification.
No sample metadata fields
View SamplesElucidating the top of the mammary epithelial cell hierarchy is highly important for understanding its regeneration capabilities and identifying target cells for transformation. Aiming for enriched mammary epithelial stem cell population, CD200highCD200R1high epithelial cells were identified. These cells represent ~50% of the mammary repopulating units (MRUs, CD49fhigh CD24med ) and termed MRUCD200/CD200R1. Gene expression of these cells was compared to all other MRU cells, termed MRUnot CD200/CD200R1, as well as individual CD200+ population (MRU-CD200R1-) and CD200R1+ population (MRU-CD200-). Overall design: Gene expression from mammary epithelial cells carrying sorted by CD200, CD200R1 markers and MRU markers. Four populations were sequenced: MRU-positive CD200 positive and CD200R1 positive; MRU-positive and not CD200 positive CD200R1 positive; not MRU CD200 positive CD200R1 negative; not MRU CD200 negative CD200R1 positive. There are 5 replicates from 5 individual mice.
High Expression of CD200 and CD200R1 Distinguishes Stem and Progenitor Cell Populations within Mammary Repopulating Units.
Sex, Specimen part, Cell line, Subject
View SamplesmRNA expression differences between the liver and kidney of an adult male (homo sapien) were investigated using three technical replicates.
RNA-seq: an assessment of technical reproducibility and comparison with gene expression arrays.
No sample metadata fields
View SamplesA new method to measure elongation and intitiation rates Overall design: Reversal inhibition of transcription with DRB and tagging newly transcribed RNA with 4-thiouridine (4sU)
4sUDRB-seq: measuring genomewide transcriptional elongation rates and initiation frequencies within cells.
No sample metadata fields
View SamplesIdentification of genetic polymorphisms associated with inter-individual variation in immune response to Mycobacterium tuberculosis infection.
Deciphering the genetic architecture of variation in the immune response to Mycobacterium tuberculosis infection.
Sex
View SamplesCharacterization of genes associated with adipose tissue is key to understanding the pathogenesis of obesity and developing treatments for this disorder. Differential gene expression in the adipose tissue has been described in adulthood but none studies have been developed on childhood. The purpose of this study was to compare gene expression in omental adipose tissue from obese prepubertal and normal weight children. We selected 5 obese (BMI adjusted for age and sex z score >2) and 6 normal weight children. RNA was extracted from omental adipose tissue biopsies and cRNA was hybridizated on the human genome U133 Plus 2.0 Arrays (Affymetrix). Microarray experiments were performed for each sample, and selected group of gene expression values were confirmed with real-time RT-PCR in 10 obese and 10 normal weigth prepubertal children. 1276 genes were found to be differentially expressed at P<0.05. Of those differential genes, 201 were upregulated (Fc>2) and 42 were downregulated (Fc<-2). Genes involved in metabolic and signalling pathways were altered in childhood obesity.
Genome-wide expression in visceral adipose tissue from obese prepubertal children.
Sex, Age, Specimen part
View Samples