We present a new wholly defined Affymetrix spike-in dataset consisting of 18 microarrays. Over 5700 RNAs are spiked in at relative concentrations ranging from 1- to 4-fold, and the arrays from each condition are balanced with respect to both total RNA amount and degree of positive- versus negative-fold change. We use this new Platinum Spike dataset to evaluate microarray analysis routes and contrast the results to those achieved using our earlier Golden Spike dataset.
Preferred analysis methods for Affymetrix GeneChips. II. An expanded, balanced, wholly-defined spike-in dataset.
No sample metadata fields
View SamplesSkeletal muscles are formed in a variety of shapes and sizes, and this diversity impacts muscle function and disease susceptibility. To understand how muscle diversity is generated, we performed gene expression profiling of muscle subsets from Drosophila embryos. By comparing the transcriptional profiles of two muscle subsets, we identified a core group of founder cell-enriched genes. We screened mutant embryos for muscle defects and identified Sin3A and 10 other transcription and chromatin regulators as having novel functions in the Drosophila embryonic somatic musculature. Sin3A is required for the morphogenesis of a subset of muscles, and Sin3A mutants display muscle loss and misattachment. Additionally, misexpression of identity gene transcription factors in Sin3A heterozygous embryos leads to direct transformations of one muscle into another, while overexpression of Sin3A results in the reverse transformation. Our data implicate Sin3A as a key buffer controlling muscle responsiveness to transcription factors in the formation of muscle identity, thereby generating tissue diversity.
Whole-genome analysis of muscle founder cells implicates the chromatin regulator Sin3A in muscle identity.
Specimen part
View SamplesTo identify gene expression changes associated with Crtc1 deficiency, we performed genome-wide transcriptome profile analyses by using mouse cDNA microarrays in the cortex of Crtc1/ and WT female mice
Involvement of the agmatinergic system in the depressive-like phenotype of the Crtc1 knockout mouse model of depression.
Sex, Specimen part
View SamplesAn important but largely unmet challenge in understanding the mechanisms that govern formation of specific organs is to decipher the complex and dynamic genetic programs exhibited by the diversity of cell types within the tissue of interest. Here, we use an integrated genetic, genomic and computational strategy to comprehensively determine the molecular identities of distinct myoblast subpopulations within the Drosophila embryonic mesoderm at the time that cell fates are initially specified. A compendium of gene expression profiles was generated for primary mesodermal cells purified by flow cytometry from appropriately staged wild-type embryos and from twelve genotypes in which myogenesis was selectively and predictably perturbed. A statistical meta-analysis of these pooled datasetsbased on expected trends in gene expression and on the relative contribution of each genotype to the detection of known muscle genesprovisionally assigned hundreds of differentially expressed genes to particular myoblast subtypes. Whole embryo in situ hybridizations were then used to validate the majority of these predictions, thereby enabling true positive detection rates to be estimated for the microarray data. This combined analysis reveals that myoblasts exhibit much greater gene expression heterogeneity and overall complexity than was previously appreciated. Moreover, it implicates the involvement of large numbers of uncharacterized, differentially expressed genes in myogenic specification and subsequent morphogenesis. These findings also underscore a requirement for considerable regulatory specificity for generating diverse myoblast identities. Finally, to illustrate how the developmental functions of newly identified myoblast genes can be efficiently surveyed, a rapid RNA interference assay that can be scored in living embryos was developed and applied to selected genes. This integrated strategy for examining embryonic gene expression and function provides a substantially expanded framework for further studies of this model developmental system.
An integrated strategy for analyzing the unique developmental programs of different myoblast subtypes.
No sample metadata fields
View SamplesTwo-dimensional patterning of the follicular epithelium in Drosophila oogenesis is required for the formation of three-dimensional eggshell structures. Our analysis of a large number of published gene expression patterns in the follicle cells suggests that they follow a simple combinatorial code based on six spatial building blocks and the operations of union, difference, intersection, and addition. The building blocks are related to the distribution of inductive signals, provided by the highly conserved epidermal growth factor receptor and Decapentaplegic
A combinatorial code for pattern formation in Drosophila oogenesis.
No sample metadata fields
View SamplesThe primary goal of toxicology and safety testing is to identify agents that have the potential to cause adverse effects in humans. Unfortunately, many of these tests have not changed significantly in the past 30 years and most are inefficient, costly, and rely heavily on the use of animals. The rodent cancer bioassay is one of these safety tests and was originally established as a screen to identify potential carcinogens that would be further analyzed in human epidemiological studies. Today, the rodent cancer bioassay has evolved into the primary means to determine the carcinogenic potential of a chemical and generate quantitative information on dose-response behavior in chemical risk assessments. Due to the resource-intensive nature of these studies, each bioassay costs $2 to $4 million and takes over three years to complete. Over the past 30 years, only 1,468 chemicals have been tested in a rodent cancer bioassay. By comparison, approximately 9,000 chemicals are used by industry in quantities greater than 10,000 lbs and nearly 90,000 chemicals have been inventoried by the U.S. Environmental Protection Agency as part of the Toxic Substances Control Act. Given the disparity between the number of chemicals tested in a rodent cancer bioassay and the number of chemicals used by industry, a more efficient and economical system of identifying chemical carcinogens needs to be developed.
Application of genomic biomarkers to predict increased lung tumor incidence in 2-year rodent cancer bioassays.
Sex, Age, Subject
View SamplesThe capacity of cancer cells to undergo epithelial mesenchymal trans-differentiation has been implicated as a factor driving metastasis, through the acquisition of enhanced migratory/invasive cell programs and the engagement of anti-apoptotic mechanisms promoting drug and radiation resistance. Our aim was to define molecular signaling changes associated with mesenchymal trans-differentiation in two KRas mutant NSCLC models. We focused on central transcription and epigenetic regulators predicted to be important for mesenchymal cell survival. Overall design: Haley, J.A., Haughney, E., Ullman, E., Bean, J., Haley, J.D.* and Fink, M.Y. (2014) 'Altered Transcriptional Control Networks with Trans-Differentiation of Isogenic Mutant KRas NSCLC Models' Front. Oncology, doi/10.3389/fonc.2014.00344.
Altered Transcriptional Control Networks with Trans-Differentiation of Isogenic Mutant-KRas NSCLC Models.
Treatment, Subject
View SamplesPolycomb repressive complex-2 (PRC2) is a group of proteins that play important role during development and in cell differentiation. PRC2 is a histone-modifying complex that catalyses methylation of lysine 27 of histone H3 (H3K27me3) at differentiation genes leading to their transcriptional repression. JARID2 is a co-factor of PRC2 and is important for targeting PRC2 to chromatin as well as modulating its activity. Here, we show that in many human cells, including human epidermal keratinocytes, JARID2 predominantly exists as a novel low molecular weight form, which lacks the N-terminal PRC2-interacting domain (?N-JARID2). We show that ?N-JARID2 is a cleaved product of full-length JARID2 spanning the C-terminal conserved region consisting of jumonji domains. JARID2 knockout in keratinocytes results in up-regulation of cell cycle genes and repression of many epidermal differentiation genes. Surprisingly, repression of epidermal differentiation genes in JARID2-null keratinocytes can be relieved by expression of ?N-JARID2 suggesting that this form promotes activation of these genes and has opposing function to that of PRC2 in regulation of differentiation. We propose that a switch from expression of full-length JARID2 to ?N-JARID2 is important for the up-regulation of genes during differentiation. Overall design: RNA-seq analysis of Wildtype and JARID2-null keratinocytes (HaCaTs) on day 0 and day 3 of calcium induced differentiation.
A novel form of JARID2 is required for differentiation in lineage-committed cells.
Specimen part, Cell line, Subject
View SamplesThe transcriptomes of FACS-sorted siglec-F+ alveolar macrophages and siglec-f- CD11b+ exudative macrophages from inducible airway GM-CSF over-expressing transgenic mice (DTGM) were compared to non-inducible littermate controls during influenza A virus infection. Overall design: Examination of effect of GM-CSF on airway macrophages during influenza A virus infection
GM-CSF overexpression after influenza a virus infection prevents mortality and moderates M1-like airway monocyte/macrophage polarization.
Sex, Specimen part, Cell line, Subject
View SamplesThese data provide scientific information to understand the mechanism of action of lapatinib resistance in HER2-positive patients and to test the combination of HER2-targeted agents and GSK1363089 (foretinib) in the clinic by using an acquired lapatinib-resistant cell line.
Novel mechanism of lapatinib resistance in HER2-positive breast tumor cells: activation of AXL.
Specimen part, Cell line, Treatment
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