The metabolic syndrome (MetS) is a collection of co-occurring complex disorders including obesity, hypertension, dyslipidemia, and insulin resistance. The Lyon Hypertensive (LH) and Lyon Normotensive (LN) rats are models of MetS sensitivity and resistance, respectively. To identify genetic determinants and mechanisms underlying MetS, 169 rats from an F2 intercross between LH and LN were studied. Multi-dimensional data were obtained including genotypes of 1536 SNPs, 23 physiological traits including blood pressure, plasma lipid and leptin levels, and body weight/adiposity, and more than 150 billion nucleotides of RNA-seq reads from the livers of 36 F2 individuals, 6 LH and 6 LN individuals. We identified 17 pQTLs (physiological quantitative trait loci) and 1200 eQTLs (gene expression quantitative trait loci). Systems biology methods were applied to identify 18 candidate MetS genes, including genes (Prcp and Aqp11) previously shown to be MetS-related. We found an eQTL hotspot on RNO17, which was also located within pQTLs for MetS-related traits. The genes regulated by this eQTL hotspot were mainly in two co-expression network modules (a mitochondria related module and a gene regulation related module) and were predicted to causally affect many MetS-related traits. Multiple evidences strongly and consistently support RGD1562963, a gene regulated in cis by this eQTL hotspot and possibly related to RNA stability, as the eQTL driver gene directly affected by genetic variation between LH and LN rats; the expression of this gene is also correlated with MetS-related traits. Our study sheds light on the intricate pathogenesis of MetS and proved that systems biology with high-throughput sequencing is a powerful method to study the etiology of complicated diseases. Overall design: RNA-Seq of the liver of 6 LH (Lyon Hypertensive) rats and 6 LN (Lyon Normotensive) rats and 36 F2 rats.
Systems biology with high-throughput sequencing reveals genetic mechanisms underlying the metabolic syndrome in the Lyon hypertensive rat.
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View SamplesFour male SHR/Ola, BN and SHR-18 rats were fed a normal diet and sacrificed at 9 weeks of age. Four male SHR/Ola and SHR-18 rats at 8 weeks of age were fed 1% NaCl for one week and then sacrificed. Kidneys were removed and frozen in liquid nitrogen for all 20 animals. Total RNA was isolated, labelled cRNA was generated and hybridised to Affymetrix Rat RG-U34ABC arrays.
Dissection of chromosome 18 blood pressure and salt-sensitivity quantitative trait loci in the spontaneously hypertensive rat.
Sex, Age, Specimen part
View SamplesLeft ventricular mass (LVM) and cardiac gene expression are complex traits regulated by factors both intrinsic and extrinsic to the heart. To dissect the major determinants of LVM, we combined expression quantitative trait locus1 and quantitative trait transcript (QTT) analyses of the cardiac transcriptome in the rat. Using these methods and in vitro functional assays, we identified osteoglycin (Ogn) as a major candidate regulator of rat LVM, with increased Ogn protein expression associated with elevated LVM. We also applied genome-wide QTT analysis to the human heart and observed that, out of 22,000 transcripts, OGN transcript abundance had the highest correlation with LVM. We further confirmed a role for Ogn in the in vivo regulation of LVM in Ogn knockout mice. Taken together, these data implicate Ogn as a key regulator of LVM in rats, mice and humans, and suggest that Ogn modifies the hypertrophic response to extrinsic factors such as hypertension and aortic stenosis.
Integrated genomic approaches implicate osteoglycin (Ogn) in the regulation of left ventricular mass.
Sex, Age, Specimen part
View SamplesTh1 and Th2 cells arise from a common precursor cell in response to triggering through the TCR and cytokine receptors for IL-12 or IL-4. This leads to activation of complex signaling pathways, which are not known in detail. Disturbances in the balance between type 1 and type 2 responses can lead to certain immune-mediated diseases. Thus, it is important to understand how Th1 and Th2 cells are generated. To clarify the mechanisms as to how IL-12 and IL-4 induce Th1 and Th2 differentiation and how TGF-beta can inhibit this process, we have used oligonucleotide arrays to examine the early polarization of Th1 and Th2 cells in the presence and absence of TGF-beta after 0, 2, 6 and 48 hours of polarization.
Identification of novel genes regulated by IL-12, IL-4, or TGF-beta during the early polarization of CD4+ lymphocytes.
No sample metadata fields
View SamplesThe bovine chromaffin cell (BCC) is a unique modela highly homogeneous and accessible neuroendocrine cellin which to study gene regulation through first messenger-initiated signaling pathways that are specific to post-mitotic cells. BCCs were treated with tumor necrosis factor (TNF) or pituitary adenylate cyclase activating polypeptide (PACAP), two critical regulators of neural cell transcriptional programming during inflammation that act on TNFR2 and PAC1 receptors, respectively, in post-mitotic neuroendocrine cells. Transcripts which were significantly up regulated by either or both first messenger were identified from microarray analysis using two bovine oligonucleotide arrays (Affymetrix and Agilent) followed by statistical analysis with Partek Genomic suite. Microarray data were combined from the two arrays using qRT-PCR sampling validation, and the first-messenger transcriptome derived from TNF and PACAP signaling were compared. More than 90 percent of the genes up regulated either by TNF or PACAP were specific to a single first messenger. BioBase suite, DIRE and Opossum were used to identify common promoter/enhancer response elements that control the expression of TNF- or PACAP-stimulated genes. Bioinformatic analysis revealed that distinct groups of transcription factors control the expression of genes up regulated by either TNF or PACAP . Most of the genes up regulated by TNF contained response elements for members of the Rel transcription factor family, suggesting TNF-TNFR2 signaling mainly through the NF-kB signaling pathway. On the other hand, the PACAP regulated genes showed no enrichment for any single response element, containing instead response elements for combinations of transcription factors allowing activation through multiple signaling pathways, including cAMP, calcium and ERK, in neuroendocrine cells. Pharmacological strategies for mimicking neuroprotection by either PACAP or TNF in the context of CNS injury or degeneration in disease might focus on individual downstream gene activation pathways to achieve greater specificity in vivo.
Neuropeptides, growth factors, and cytokines: a cohort of informational molecules whose expression is up-regulated by the stress-associated slow transmitter PACAP in chromaffin cells.
Specimen part
View SamplesCharacterization of the underlying genetic defects in patients with a rare and peculiar phenotype is challenging. Here we have utilized whole genome expression profiling, and identified a homozygous germline mutation in the DDB2 gene in a patient with several facial tumors. The feasibility of using blood derived RNA, diminishing costs of the technology, and the limited number of samples needed provide this approach a powerful new tool that may substantially aid in such gene identification efforts.
Blood-derived gene-expression profiling in unravelling susceptibility to recessive disease.
No sample metadata fields
View SamplesThe aim of this study was to determine the changes in gene expression of rice root tips when they came in to contact with a hard layer (60% wax layer). Three categories of root tips were sampled; tips before the hard layer, tips that had come into contact with the hard layer and root tips which had buckled after coming into contact with the hard layer.
A bioinformatic and transcriptomic approach to identifying positional candidate genes without fine mapping: an example using rice root-growth QTLs.
No sample metadata fields
View SamplesAnalysis of T-cells lacking the proprotein convertase furin. Proprotein convertases promote the proteolytic maturation of proproteins. Furin is induced in activated T-cells. Results provide insight into the function of furin in T-cells.
Proprotein convertase FURIN regulates T cell receptor-induced transactivation.
Age, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Tissue-specific pioneer factors associate with androgen receptor cistromes and transcription programs.
Specimen part, Treatment
View SamplesWe report the in vivo androgen receptor (AR) binding sites in murine prostate, epididymis and kidney in response to physiological androgen testosterone using ChIP-sequencing and gene expression profiling by microarray. From AR cistrome analysis, we identified tissue-specific collaborating factors i.e. FoxA1 in prostate, Hnf4a in kidney and AP2a in epididymis and validated by ChIP-seq. The ChIP experiments have been performed using antibodies specific to AR, FoxA1, Hnf4a, AP-2a and IgG non-specific antibody as a negative control.
Tissue-specific pioneer factors associate with androgen receptor cistromes and transcription programs.
Specimen part
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