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SRP035388
Drosophila melanogaster
6 Downloadable Samples
Illumina Genome Analyzer IIx
Description
Background: RNA-seq is revolutionizing the way we study transcriptomes. mRNA can be surveyed without prior knowledge of gene transcripts. Alternative splicing of transcript isoforms and the identification of previously unknown exons are being reported. Initial reports of differences in exon usage, and splicing between samples as well as quantitative differences among samples are beginning to surface. Biological variation has been reported to be larger than technical variation. In addition, technical variation has been reported to be in line with expectations due to random sampling. However, strategies for dealing with technical variation will differ depending on the magnitude. The size of technical variance, and the role of sampling are examined in this manuscript. Results: Independent Solexa/Illumina experiments containing technical replicates are analyzed. When coverage is low, large disagreements between technical replicates are apparent. Exon detection between technical replicates is highly variable when the coverage is less than 5 reads per nucleotide and estimates of gene expression are more likely to disagree when coverage is low. Although large disagreements in the estimates of expression are observed at all levels of coverage. Conclusions: Technical variability is too high to ignore. Technical variability results in inconsistent detection of exons at low levels of coverage. Further, the estimate of the relative abundance of a transcript can substantially disagree, even when coverage levels are high. This may be due to the low sampling fraction and if so, it will persist as an issue needing to be addressed in experimental design even as the next wave of technology produces larger numbers of reads. We provide practical recommendations for dealing with the technical variability, without dramatic cost increases. Overall design: Three independent samples of D. melanogaster female heads were collected with each sample representing a unique pool of biological material. Each sample was prepared according to manufacturer's instructions and then the same library was run on two lanes of a Solexa/Illumina flow cell, resulting in two technical replicates for each biological replicate, runs were 36 base-pair paired end.
Publication Title
A flexible Bayesian method for detecting allelic imbalance in RNA-seq data.
Sample Metadata Fields
Sex, Specimen part, Cell line, Subject
View Samples- Drosophila melanogaster
- 38 Downloadable Samples
- Illumina Genome Analyzer IIx
Description
Drosophila melanogaster adult males perform an elaborate courtship ritual to entice females to mate. fruitless (fru), a gene that is one of the key regulators of male courtship behavior, encodes multiple male-specific isoforms (FruM). These isoforms vary in their carboxy-terminal zinc finger domains, which are predicted to facilitate DNA binding. By over-expressing individual FruM isoforms in fru-expressing neurons in either males or females and assaying the global transcriptional response by RNA-sequencing, we show that three FruM isoforms have different regulatory activities that depend on the sex of the fly. We identified several sets of genes regulated downstream of FruM isoforms. Overall design: RNA seqeuncing was performed on mRNA derived from adult male or female heads, for a total of 39 samples. These samples included two wild type genotypes (Berlin and Canton-S), two transheterozygous mutants for fru P1 (Df(3R)P14/Df(3R)fru4-40 and fruw12/ Df(3R)ChaM5), and 3 overexpressing genotypes (fru P1-Gal4: UAS-FruMA, UAS-FruMB, UAS-FruMC). There were at least 3 replicates from biological samples for all sex by genotype combinations.
Publication Title
Sex Differences in Drosophila Somatic Gene Expression: Variation and Regulation by doublesex.
Sample Metadata Fields
Sex, Specimen part, Cell line, Subject
View Samples- Drosophila melanogaster
- 9 Downloadable Samples
- Illumina Genome Analyzer IIx
Description
The Drosophila sex determination hierarchy consists of a splicing cascade with sex-specific transcription directing somatic sexual dimorphism. Our understanding of this pathway, and many others, is incomplete. Here we pioneer an approach to expand our knowledge of gene regulatory networks (GRNs) by leveraging natural genetic variation. This approach is generalizable to any natural population, including humans. Two studies from Drosophila female head tissue were used – the DSPR collection (alleles from 15 natural variants) and F1-hybrid collection (alleles from heterozygotes of 75 isogenic lines crossed to w1118) – in a structural equation model (SEM) analysis. We expanded the sex hierarchy GRN by adding novel links among genes in the pathway and by adding novel genes to the pathway. A link from fruitless (fru) to Sex-lethal (Sxl) was found in both populations, which is supported by the presence of fru binding sites in the Sxl locus. The splicing factors male-specific lethal 2 and Rm62 were correctly identified as downstream targets of Sxl. There were 754 additional candidate genes for an expanded sex hierarchy GRN. These candidates were enriched for genes with sex-biased splicing and many components of the spliceosome were placed in the GRN. As with other population-genetic analyses, the number of alleles limits the number of observable interactions. Network expansion was only clear in the F1-hybrid population, which has an average of twice as many alleles as the DSPR population. Independent studies of doublesex and transformer mutants support many novel connections, including evidence for a link between the sex hierarchy and metabolism, with the inclusion of Insulin-like receptor in the sex hierarchy GRN. Overall design: RNA sequencing was performed on mRNA derived from adult male or female heads, for a total of 9 samples. These samples included females that produce the male isoform of dsx [w/+;DsxD/dsxm+r15 (XX)], and two dsx mutants: females [w/+; dsxm+r15/dsxd+r3 (XX)] and males [w;dsxm+r15/dsxd+r3 (XY)]. Two wild type genotypes (Berlin and Canton-S) were sequenced at the same time, but have previously been published as part of GSE50515. There were at least 3 replicates from biological samples.
Publication Title
Sex Differences in Drosophila Somatic Gene Expression: Variation and Regulation by doublesex.
Sample Metadata Fields
Sex, Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 15 Downloadable Samples
Affymetrix Human Genome U133A Array (hgu133a)
Description
Quiescent and dividing hemopoietic stem cells (HSC) display marked differences in their ability to move between the peripheral circulation and the bone marrow. Specifically, long-term engraftment potential predominantly resides in the quiescent HSC subfraction, and G-CSF mobilization results in the preferential accumulation of quiescent HSC in the periphery. In contrast, stem cells from chronic myeloid leukemia (CML) patients display a constitutive presence in the circulation. To understand the molecular basis for this, we have used microarray technology to analyze the transcriptional differences between dividing and quiescent, normal, and CML-derived CD34+ cells.
Publication Title
Transcriptional analysis of quiescent and proliferating CD34+ human hemopoietic cells from normal and chronic myeloid leukemia sources.
Sample Metadata Fields
Specimen part, Disease, Subject
View Samples- Homo sapiens
- 36 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [CDF: huex10stv2_67_020 (huex10st)
Description
Glucocorticoids (GCs) are a central component in treating childhood acute lymphoblastic leukemia (chALL). They mainly act via regulating gene transcription. However, control of mRNA translation by GC has never been assessed systematically. In our research, T- and precursor B-ALL cells were cultured with and without GC for 6 hours and subjected to translational profiling, a technique combining sucrose gradient fractionation and microarray analysis of mRNA in different fractions. Analysis of GC regulation in different pools revealed no significant differences in regulation of mRNA translation by GC, suggesting no evidence for translational regulation by GC.
Publication Title
Translational profiling in childhood acute lymphoblastic leukemia: no evidence for glucocorticoid regulation of mRNA translation.
Sample Metadata Fields
Cell line, Treatment
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Microarray studies revealed that as a first hit, SV40 T/t-antigen causes deregulation of 462 genes in mammary gland cells (ME-cells) of WAP-SVT/t transgenic animals. The majority of deregulated genes are cell-proliferation specific and Rb-E2F dependent, causing ME-cell proliferation and gland hyperplasia but not breast cancer formation. In the breast tumor cells, a further 207 genes are differentially expressed, most of them belonging to the cell communication category. In tissue culture, breast tumor cells frequently switch off WAP-SVT/t transgene expression and regain the morphology and growth characteristics of normal-ME-cells, although the tumor-revertant cells are aneuploid and only 114 genes regain the expression level of normal-ME-cells. The profile of retransformants shows that only 38 deregulated genes appear to be tumor-relevant and that none of them is considered to be a typical breast cancer gene.
Publication Title
Gene expression profiling: cell cycle deregulation and aneuploidy do not cause breast cancer formation in WAP-SVT/t transgenic animals.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 33 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Molecular Aging of Human Liver: An Epigenetic/Transcriptomic Signature.
Sample Metadata Fields
Sex, Age, Specimen part, Disease
View Samples- Homo sapiens
- 33 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Gene expression profiling of liver biopsies collected from 33 healthy liver donors ranging from 13 to 90 years old. The Affymetrix HG-U133 Plus 2.0 GeneChip platform was used to evaluate gene-expression.
Publication Title
Molecular Aging of Human Liver: An Epigenetic/Transcriptomic Signature.
Sample Metadata Fields
Sex, Age, Specimen part, Disease
View Samples- Homo sapiens
- 32 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [transcript (gene) version (huex10st)
Description
Alternative promoters (APs) occur in >30% protein-coding genes and contribute to proteome diversity. However, large-scale analyses of AP regulation are lacking, and little is known about their potential physiopathologic significance. To better understand the transcriptomic impact of estrogens, which play a major role in breast cancer, we analyzed gene and AP regulation by estradiol in MCF7 cells using pan-genomic exon arrays. We thereby identified novel estrogen-regulated genes, and determined the regulation of AP-encoded transcripts in 150 regulated genes. In <30% cases, APs were regulated in a similar manner by estradiol, while in >70% cases, they were regulated differentially. The patterns of AP regulation correlated with the patterns of estrogen receptor (ER) and CCCTC-binding factor (CTCF) binding sites at regulated gene loci. Interestingly, among genes with differentially regulated APs, we identified cases where estradiol regulated APs in an opposite manner, sometimes without affecting global gene expression levels. This promoter switch was mediated by the DDX5/DDX17 family of ER coregulators. Finally, genes with differentially regulated promoters were preferentially involved in specific processes (e.g., cell structure and motility, and cell cycle). We show in particular that isoforms encoded by the NET1 gene APs, which are inversely regulated by estradiol, play distinct roles in cell adhesion and cell cycle regulation, and that their expression is differentially associated with prognosis in ER+ breast cancer. Altogether, this study identifies the patterns of AP regulation in estrogen-regulated genes, demonstrates the contribution of AP-encoded isoforms to the estradiol-regulated transcriptome, as well as their physiopathologic significance in breast cancer.
Publication Title
Estrogen regulation and physiopathologic significance of alternative promoters in breast cancer.
Sample Metadata Fields
Disease, Disease stage, Cell line, Time
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Gene 2.1 ST Array (hugene21st)
Description
This study was designed to compare the global gene expression change induced by the circulating, prodomain bound forms of BMP9 and BMP10 (pro-BMP9 and pro-BMP10) in human pulmonary arterial endothelial cells (PAECs). This is different from many previous studies which used the growth factor domain of BMP9 and/or BMP10.
Publication Title
Molecular basis of ALK1-mediated signalling by BMP9/BMP10 and their prodomain-bound forms.
Sample Metadata Fields
Sex, Age
View Samples