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GSE30697
Homo sapiens
94 Downloadable Samples
Illumina HumanHT-12 V3.0 expression beadchip
Description
Recent genome-wide association studies (GWAS) have identified a number of novel genetic associations with complex human diseases. In spite of these successes, results from GWAS generally explain only a small proportion of disease heritability, an observation termed the missing heritability problem. Several sources for the missing heritability have been proposed, including the contribution of many common variants with small individual effect sizes, which cannot be reliably found using the standard GWAS approach. The goal of our study was to explore a complementary approach, which combines GWAS results with functional data in order to identify novel genetic associations with small effect sizes. To do so, we conducted a GWAS for lymphocyte count, a physiologic quantitative trait associated with asthma, in 462 Hutterites. In parallel, we performed a genome-wide gene expression study in lymphoblastoid cell lines (LCLs) from 96 Hutterites. We found significant support for genetic associations using the GWAS data when we considered variants near the 193 genes whose expression levels across individuals were most correlated with lymphocyte counts. Interestingly, these variants are also enriched with signatures of an association with asthma susceptibility, an observation we were able to replicate. The associated loci include genes previously implicated in asthma susceptibility, as well as novel candidate genes enriched for functions related to T cell receptor signaling and ATP synthesis. Our results, therefore, establish a new set of asthma susceptibility candidate genes. More generally, our observations support the notion that many loci of small effects influence variation in lymphocyte count and asthma susceptibility.
Publication Title
The combination of a genome-wide association study of lymphocyte count and analysis of gene expression data reveals novel asthma candidate genes.
Sample Metadata Fields
Sex
View Samples- Mus musculus
- 21 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
During development of the central nervous system (CNS), cycling uncommitted progenitor cells give rise to a variety of distinct neuronal and glial cell types. As these different cell types are born, they progress from newly specified cells to fully differentiated neurons and glia. In order to define the developmental processes of individual cell types, single cell expression profiling was carried out on developing ganglion and amacrine cells of the murine retina. Individual cells from multiple developmental stages were isolated and profiled on Affymetrix oligonucleotide arrays. These experiments have yielded an expanded view of the processes underway in developing retinal ganglion and amacrine cells, as well as several hundred new marker genes for these cell types. In addition, this study has allowed for the definition of some of the molecular heterogeneity both between developing ganglion and amacrine cells and among subclasses of each cell type.
Publication Title
Molecular heterogeneity of developing retinal ganglion and amacrine cells revealed through single cell gene expression profiling.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 25 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Lymphangioleiomyomatosis (LAM) is characterized by cystic lung destruction caused by smooth, muscle-like LAM cells which have mutations in the tumor suppressor genes Tuberous Sclerosis Complex (TSC) 1 or 2, and the capacity to metastasize. Since chemokines and their receptors function in chemotaxis of metastatic cells, we hypothesized that LAM cells may be recruited by chemokine(s) in the lung. Quantification of 25 chemokines in bronchoalveolar lavage fluid from LAM patients and healthy volunteers revealed that concentrations of MCP-1/CCL2, GROa/CXCL1 and ENA-78/CXCL5 were significantly higher in samples from LAM patients than healthy volunteers. In this transcript analysis, expression of chemokine and chemokine receptor mRNA in LAM cells differed from those in melanoma and smooth muscle cells. Subsequent immunohistochemistry of lung sections from 30 LAM patients confirmed protein expression of chemokines and these receptors varied among LAM patient and differed from that seen in breast cancer and melanoma cells. . In vitro, MCP-1/CCL2 induced selective migration of cells showing loss of heterozygosity of TSC2 from a heterogeneous populations of cells grown from explanted LAM lungs. In addition, the frequencies of single-nucleotide polymorphisms in the MCP-1 gene promoter region differed significantly in LAM patients and healthy volunteers (p=0.018), and one polymorphism was associated significantly more frequently with the decline of lung function. These observations are consistent with the notion that chemokines such as MCP-1 may serve to specify site of LAM cell metastasis.
Publication Title
Chemokine-enhanced chemotaxis of lymphangioleiomyomatosis cells with mutations in the tumor suppressor TSC2 gene.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 11 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Patients with tuberous sclerosis complex (TSC) develop hamartomas containing biallelic inactivating mutations in either TSC1 or TSC2, resulting in mammalian target of rapamycin (mTOR) activation. Hamartomas overgrow epithelial and mesenchymal cells in TSC skin. The pathogenetic mechanisms for these changes had not been investigated, and the existence or location of cells with biallelic mutations (two-hit cells) that resulted in mTOR activation was unclear. We compared TSC skin hamartomas (facial angiofibromas and periungual fibromas) to normal-appearing skin of the same patient, and observed more proliferation and mTOR activation in hamartoma epidermis. Two-hit cells were not detected in the epidermis. Fibroblast-like cells in the dermis, however, exhibited allelic deletion of TSC2, in both touch preparations of fresh tumor samples and cells grown from TSC skin tumors, suggesting that increased epidermal proliferation and mTOR activation were not caused by second-hit mutations in the keratinocytes but by mesenchymal-epithelial interactions. Gene expression arrays, used to identify potential paracrine factors released by mesenchymal cells, revealed more epiregulin mRNA in fibroblast-like angiofibroma and periungual fibroma cells than in fibroblasts from normal-appearing skin of the same patient. Elevation of epiregulin mRNA was confirmed using real-time PCR, and increased amounts of epiregulin protein were demonstrated using immunoprecipitation and ELISA. Epiregulin stimulated keratinocyte proliferation and phosphorylation of ribosomal protein S6 in vitro. These results suggest that hamartomatous TSC skin tumors are induced by paracrine factors released by two-hit cells in the dermis, and that proliferation with mTOR activation of the overlying epidermis is an effect of epiregulin.
Publication Title
Mesenchymal-epithelial interactions involving epiregulin in tuberous sclerosis complex hamartomas.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Determination of differential expression of genes in the thyroid of pendrin (Slc26a4) heterozygous and knockout mice at a time point corresponding to maximal thyroid gland activity, postnatal day 15 (P15).
Publication Title
Developmental delays consistent with cochlear hypothyroidism contribute to failure to develop hearing in mice lacking Slc26a4/pendrin expression.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 3 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Mesenchyme-derived cells in the human airway wall including airway smooth muscle cells, fibroblasts and myofibroblasts are known to play important roles in airway remodeling. The lack of specific phenotypic markers makes it difficult to define these cell populations in primary cultures. The objectives of this study were to evaluate reported markers and to identify novel markers to define these cell types.
Publication Title
Can lineage-specific markers be identified to characterize mesenchyme-derived cell populations in the human airways?
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 12 Downloadable Samples
Description
We report a novel technique, Affinity-seq, that for the first time identifies both the genome-wide binding sites of DNA-binding proteins and quantitates their relative affinities. We have applied this in vitro technique to PRDM9, the zinc-finger protein that activates genetic recombination, obtaining new information on the regulation of hotspots, whose locations and activities determine the recombination landscape. We identified 31,770 binding sites in the mouse genome for the PRDM9Dom2 variant. Comparing these results with hotspot usage in vivo, we find that less than half of potential PRDM9 binding sites are utilized in vivo. We show that hotspot usage is increased in actively transcribed genes and decreased in genomic regions containing H3K9me2/3 histone marks or bound to the nuclear lamina. These results show that a major factor determining whether a binding site will become an active hotspot and what its activity will be are constraints imposed by prior chromatin modifications on the ability of PRDM9 to bind to DNA in vivo. These constraints lead to the presence of long genomic regions depleted of recombination. Overall design: The terminal zinc finger domain of PRDM9Dom2 (PRDM9?ZnF1Dom2, 412–847 aa), the allele present in C57BL/6J (B6) mice was cloned and tagged with 6His-HALO and then expressed in E. coli. DNA sheared to 180–200 bp is provided in considerable excess to provide competition between DNA binding sites. Following binding, DNA–protein complexes are then isolated on streptavidin beads and the DNA extracted for deep sequencing. Two replicate Affinity-seq samples were sequenced at 100-bp reads using the Illumina HiSeq 2500. Alignments to the mm9 mouse genome were obtained utilizing BWA v1.2.3 with default parameters and reads which failed to align to unique positions in the genome were discarded. Peaks were called individually for the two replicates with MACS2 at a p value threshold of 0.01 utilizing a control dataset obtained by sequencing the input DNA and subsequently compared, leading ultimately to combining the two replicates for definitive analysis.
Publication Title
Affinity-seq detects genome-wide PRDM9 binding sites and reveals the impact of prior chromatin modifications on mammalian recombination hotspot usage.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 8 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Changes in the transcript profile due to ABCA1 expression in murine liver samples was evaluated in LDL receptor -/- genetic backgrounds.
Publication Title
ABCA1 overexpression in the liver of LDLr-KO mice leads to accumulation of pro-atherogenic lipoproteins and enhanced atherosclerosis.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Curcumin is a potent anti-inflammatory compound capable of preventing chemically induced colitis in mice.
Publication Title
Protective effects of dietary curcumin in mouse model of chemically induced colitis are strain dependent.
Sample Metadata Fields
Treatment
View Samples- Homo sapiens
- 44 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
We sought to ascertain the time-course of transcriptional events that occur in human skeletal muscle at the outset of resistance exercise (RE) training in RE nave individuals, and determine if the magnitude of any response was associated with exercise induced muscle damage. Sixteen RE nave males were recruited, 8 underwent 2 sessions of 5x30 maximum, isokinetic knee extensions (180.s-1) separated by 48 hrs. Muscle biopsies of the vastus lateralis were taken at baseline and 24 hrs after each exercise bout. Eight individuals acted as non-exercise controls with biopsies obtained at the same time intervals. Transcriptional changes were assessed by microarray, and binding of HSP27 and B-crystallin to insoluble proteins by immunohistochemistry as a measure of muscle damage. In control subjects, no probesets were significantly altered (FDR<0.05) and HSP27 and B-crystallin binding remained unchanged throughout the study. In exercised subjects, significant inter-subject variability following the initial bout of RE was observed in the muscle transcriptome, with greatest changes occurring when HSP27 and B-crystallin binding was elevated. Following the second bout of RE, the transcriptome response was more consistent among subjects revealing a cohort of probesets associated with immune activation, the suppression of oxidative metabolism and protein ubiquitination as differentially regulated. The results reveal that the initial transcriptional response to RE is highly variable in RE nave volunteers, is associated with muscle damage, and unlikely to reflect longer-term adaptations to RE training. These results highlight the importance of considering multiple time-points when determining the transcriptional response to RE and associated physiological adaptation.
Publication Title
Transient transcriptional events in human skeletal muscle at the outset of concentric resistance exercise training.
Sample Metadata Fields
Sex, Specimen part, Subject, Time
View Samples