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GSE18161
Homo sapiens
16 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Post-hybridization washing is an essential part of microarray experiments. Both, the quality of the experimental washing protocol and the adequate consideration of washing in intensity calibration ultimately affect the quality of the expression estimates extracted from the microarray intensities. We conducted experiments on GeneChip microarrays with altered protocols for washing, scanning and staining to study the probe-level intensity changes as a function of washing cycles. Particularly, three Affymetrix GeneChip HGU133plus2 arrays were hybridized and equilibrated for 16 hours in the hybridization oven. For one of the three arrays washing and staining was performed according to the manufacturers instructions. For another array the first scan was done immediately after low stringent wash and staining without intermitting stringent washing. Then, the array was stringently washed and scanned in alternating order three more times where each washing step consists of a definite number of washing cycles. The third array was low stringently washed followed by two stringent washing cycles and staining before the first scan. Subsequently it was analogously processed as array A. All three chips are repeatedly processed in a second series of alternating wash/scan-cycles which was performed using the same protocol for each chip as in the first series as described above. As in the first series the arrays were also stained a second time to compensate for any loss of bleached fluorescent dye. Analysis of the washing kinetics shows that the signal-to-noise ratio doubles roughly every ten stringent washing cycles. Washing can be characterized by time-dependent rate constants which reflect the heterogeneous character of target binding to microarray probes. We propose an empirical washing function which estimates the survival of probe bound targets. The washing function allows calibrating probe intensities for the effect of washing. On a relative scale, proper calibration for washing markedly increases expression measures especially in the limit of small and large values.
Publication Title
Washing scaling of GeneChip microarray expression.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 289 Downloadable Samples
Illumina HiSeq 2500
Description
Recent technological advances in single-cell genomics make it possible to analyze cellular heterogeneity of tumor samples. Here, we applied single-cell RNA-seq to measure the transcriptomes of 307 single cells cultured from three biopsies of three different patients with a BRAF/NRAS wild type, BRAF mutant/NRAS wild type and BRAF wild type/NRAS mutant melanoma metastasis, respectively. Analysis based on self-organizing maps identified sub-populations defined by multiple gene expression modules involved in proliferation, oxidative phosphorylation, pigmentation and cellular stroma. Gene expression modules had prognostic relevance when compared with gene expression data from published melanoma samples and patient survival data. We surveyed kinome expression patterns across sub-populations of the BRAF/NRAS wild type sample and found that CDK4 and CDK2 were consistently highly expressed in the majority of cells, suggesting that these kinases might be involved in melanoma progression. Treatment of cells with the CDK4 inhibitor palbociclib restricted cell proliferation to a similar, and in some cases greater, extent than MAPK inhibitors. Finally, we identified a low abundant sub-population in this sample that highly expressed a module containing ABC transporter ABCB5, surface markers CD271 and CD133, and multiple aldehyde dehydrogenases (ALDHs), as markers for melanoma stem or initiating cells. Patient-derived cultures of the BRAF mutant/NRAS wild type and BRAF wild type/NRAS mutant metastases showed more homogeneous single-cell gene expression patterns with gene expression modules for proliferation and ABC transporters. Taken together, our results describe an intertumor and intratumor heterogeneity in melanoma short-term cultures which might be relevant for patient survival, and suggest promising targets for new treatment approaches in melanoma therapy. Overall design: RNA-seq of 307 single cells cultured from three biopsies of three different patients with a BRAF/NRAS wild type, BRAF mutant/NRAS wild type and BRAF wild type/NRAS mutant melanoma metastasis, respectively.
Publication Title
Pseudotime Dynamics in Melanoma Single-Cell Transcriptomes Reveals Different Mechanisms of Tumor Progression.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 55 Downloadable Samples
Illumina HumanMethylation450 BeadChip (HumanMethylation450_15017482), Affymetrix Human Transcriptome Array 2.0 (hta20)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Epigenome-wide and transcriptome-wide analyses reveal gestational diabetes is associated with alterations in the human leukocyte antigen complex.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 55 Downloadable Samples
- Affymetrix Human Transcriptome Array 2.0 (hta20), Illumina HumanMethylation450 BeadChip (HumanMethylation450_15017482)
Description
Gestational diabetes mellitus (GDM) affects approximately 18% of pregnancies in the United States and increases the risk of adverse health outcomes in the offspring. These adult disease propensities may be set by anatomical and molecular alterations in the placenta associated with GDM. To assess the mechanistic aspects of fetal programming, we measured genome-wide methylation (Infinium HumanMethylation450 Beadchips) and expression (Affymetrix Transcriptome Microarrays) in placental tissue of 41 GDM cases and 41 matched pregnancies without maternal complications from the Harvard Epigenetic Birth Cohort. Specific transcriptional and epigenetic perturbations associated with GDM status included alterations in the major histocompatibility complex (MHC) region, which were validated in an independent cohort, the Rhode Island Child Health Study. Gene ontology enrichment among gene regulation influenced by GDM revealed an over-representation of immune response pathways among differential expression, reflecting these coordinated changes in the MHC region. Our study represents the largest investigation of transcriptomic and methylomic differences associated with GDM, providing comprehensive insight into the molecular basis of GDM induced fetal (re)programming.
Publication Title
Epigenome-wide and transcriptome-wide analyses reveal gestational diabetes is associated with alterations in the human leukocyte antigen complex.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 16 Downloadable Samples
- Affymetrix Human Genome U219 Array (hgu219)
Description
The in-vitro analysis of the hypomethylation of the imprinting control region 1 (ICR1) within the IGF2/H19 locus is challenged by the mosaic distribution of the epimutation in tissues from children with Silver-Russell syndrome (SRS).
Publication Title
Decreased expression of cell proliferation-related genes in clonally derived skin fibroblasts from children with Silver-Russell syndrome is independent of the degree of 11p15 ICR1 hypomethylation.
Sample Metadata Fields
Specimen part, Disease
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Determining the spatial and temporal expression of genes involved in the ovulatory pathway is critical for the understanding of the role of each estrogen receptor in the modulation of folliculogenesis and ovulation. Estrogen receptor (ER) is highly expressed in ovarian granulosa cells and mice lacking ER (ERKO) are subfertile due to inefficient ovulation. Previous work has focused on isolated granulosa cells or cultured follicles and while informative, provides confounding results due to the heterogeneous cell types present including granulosa, theca and oocytes and exposure to in vitro conditions. Herein, we isolated preovulatory granulosa cells from WT and ER-null mice using laser capture microdissection to examine the genomic transcriptional response downstream of PMSG (mimicking FSH) and PMSG/hCG (mimicking LH) stimulation. This allows for a direct comparison of in vivo granulosa cells at the same stage of development from both WT and ER-null ovaries. ER-null granulosa cells showed altered expression of genes known to be regulated by FSH (Akap12 and Runx2) as well as not previously reported (Arnt2 and Pou5f1) in WT granulosa cells. Our analysis also identified 304 genes not previously associated with ER in granulosa cells. LH responsive genes including Abcb1b and Fam110c show reduced expression in ER-null granulosa cells; however novel genes including Rassf2 and Megf10 were also identified as being downstream of LH signaling in granulosa cells. Collectively, our data suggests that granulosa cells from ER-null ovaries may not be appropriately differentiated and are unable to respond properly to gonadotropin stimulation
Publication Title
The absence of ER-β results in altered gene expression in ovarian granulosa cells isolated from in vivo preovulatory follicles.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
One day before transfection, HeLa cells were seeded in 6-well culture plates (1.5 x 10e5 cells per well) or 10-cm culture dishes (4.3 x 10e5 cells per dish). siRNA duplex (at a final concentration in culture medium of 30 nM) was transfected with Lipofectamine 2000 (Invitrogen) according to the manufacturer's instructions. siRNA duplices specific for human hnRNP L, human hnRNP LL, and luciferase GL2 were from MWG Biotech (Ebersberg, Germany).
Publication Title
Diverse roles of hnRNP L in mammalian mRNA processing: a combined microarray and RNAi analysis.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 4 Downloadable Samples
- Illumina Genome Analyzer II
Description
To investigate whether U1C plays a role in splicing regulation in human system, we performed siRNA-mediated knockdown of U1C in HeLa cells and analyzed alternative splicing patterns by high-throughput RNA sequencing (RNAseq) Overall design: RNAseq performed with poly(A)+ selected total RNA from U1C-knockdown and control-treated HeLa cells
Publication Title
A novel intra-U1 snRNP cross-regulation mechanism: alternative splicing switch links U1C and U1-70K expression.
Sample Metadata Fields
Cell line, Treatment, Subject
View Samples- Homo sapiens
- 5 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Endothelial cells comprise a key component of the inflammatory response. HUVEC (human umbilical vein endothelial cells) were stimulated with interleukin-1 for 0, 0.5, 1, 2.5 and 6 hours, and analyzed using Affymetrix U133A microarrays, in order to obtain a comprehensive overview of the immediate early to early gene expression profiles. HUVEC were isolated and cultured on gelatine-coated cell culture dishes in M199 medium supplemented with 20% FCS, antibiotics, ECGS (endothelial cell growth supplement) and Heparin as described by Zhang et al., Blood 1996;88:3880-3886. HUVEC were stimulated with 100 U/ml human IL-1 (Biosource) for various periods of time, and total RNA isolated using the RNeasy kit (Qiagen) according to the manufacturer's instructions. Hybridization to one set of human U133A GeneChips (Affymetrix, Santa Clara, CA) and scanning of the arrays was carried out according to manufacturers protocols (https://www.affymetrix.com). Briefly, 5 g of total RNA was used to generate double-stranded cDNA by reverse transcription using a cDNA synthesis kit (Superscript Choice System; Life Technologies, Inc., Rockville, MD) that uses an oligo(dT)24 primer containing a T7 RNA polymerase promoter 3' to the polyT (Geneset, La Jolla, CA), followed by second-strand synthesis. Labeled cRNA was prepared from the double-stranded cDNA by in vitro transcription using T7 RNA polymerase in the presence of biotin-11-CTP and biotin-16-UTP (Enzo, Farmington, NY). The labeled cRNA was purified over RNeasy columns (Qiagen, Valencia, CA). Fifteen g of cRNA was fragmented at 94C for 35 minutes in 40 mmol/L of Tris-acetate, pH 8.1, 100 mmol/L of potassium acetate, and 30 mmol/L of magnesium acetate. The cRNA was then used to prepare 300 l of hybridization cocktail (100 mmol/L MES, 1 mol/L NaCl, 20 mmol/L ethylenediaminetetraacetic acid, 0.01% Tween 20) containing 0.1 mg/ml of herring sperm DNA (Promega, Madison, WI) and 500 g/ml of acetylated bovine serum albumin (Life Technologies, Inc.). Before hybridization, the cocktails were heated to 94C for 5 minutes, equilibrated at 45C for 5 minutes, and then clarified by centrifugation (16,000 x g) at room temperature for 5 minutes. Aliquots of this hybridization cocktail containing 15 g of fragmented cRNA were hybridized to HU133A arrays (Affymetrix, Santa Clara, CA) at 45C for 16 hours in a rotisserie oven at 60 rpm. The arrays were washed using non-stringent buffer (6xSSPE: 0.9 M sodium chloride, 0.06 M sodium phosphate, 6 mM EDTA pH 7.4) at 25C, followed by stringent buffer (100 mmol/L MES, pH 6.7, 0.1 mol/L NaCl, 0.01% Tween 20) at 50C. The arrays were stained with streptavidin-phycoerythrin (Molecular Probes, Eugene, OR), washed with 6xSSPE, incubated with biotinylated anti-streptavidin IgG, stained again with streptavidin-phycoerythrin, and washed again with 6xSSPE. The arrays were scanned using the GeneArray scanner (Affymetrix). Image analysis was performed with GeneChip software (Affymetrix, MAS 5.0). Normalization was performed by global scaling, with the arrays scaled to an average intensity of 500.
Publication Title
Deciphering regulatory patterns of inflammatory gene expression from interleukin-1-stimulated human endothelial cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Drosophila melanogaster
- 4 Downloadable Samples
- Illumina HiSeq 2500, NextSeq 500
Description
Promoter-proximal pausing of RNA polymerase II (Pol II) is a widespread transcriptional regulatory step across metazoans. Here we find that the nuclear exon junction complex (pre-EJC) is a critical and conserved regulator of this process. Depletion of pre-EJC subunits leads to a global decrease in Pol II pausing and to premature entry into elongation. This effect occurs, at least in part, via non-canonical recruitment of pre-EJC components at promoters. Failure to recruit the pre-EJC at promoters results in increased binding of the positive transcription elongation complex (P-TEFb) and in enhanced Pol II release. Notably, restoring pausing is sufficient to rescue exon skipping and the photoreceptor differentiation defect associated with depletion of pre-EJC components in vivo. We propose that the pre-EJC serves as an early transcriptional checkpoint to prevent premature entry into elongation, ensuring proper recruitment of RNA processing components that are necessary for exon definition. Overall design: polyA mRNA -seq in conditions with the indicated knockdown treatments
Publication Title
Promoter-proximal pausing mediated by the exon junction complex regulates splicing.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples