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GSE36528
Drosophila melanogaster
11 Downloadable Samples
Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Insulators delimit independent transcriptional domains within genomes by constraining enhancer and silencer action. These transcriptional effects depend upon DNA recognition by insulator binding proteins that recruit partners that protect against inappropriate long range modulation of non-target promoters. Insulator binding proteins are broadly expressed during development, with largely constitutive binding to thousands of genomic sites. Yet, tissue-specific transcriptional changes result from the loss of individual insulator binding proteins. To understand the molecular basis for such effects, we are studying the classic Drosophila insulator protein Suppressor of Hairy-wing [Su(Hw)]. Genetic studies show that loss of this broadly expressed insulator protein prevents oocyte development. To determine the basis for the block in oogenesis, we coupled transcriptional analyses in su(Hw) mutant ovaries with genome-wide definition of Su(Hw) binding in this tissue. These studies identified 71 direct targets of Su(Hw) regulation, with nearly 70% of these genes showing increased RNA accumulation when Su(Hw) is lost. Surprisingly, derepressed Su(Hw) target genes correspond to genes normally highly expressed in neural tissues, suggesting that Su(Hw) has a critical role in silencing neural genes in the ovary. Support for this postulate was obtained by genetic studies. We found that oocyte production was restored in su(Hw) mutant females that carry a deletion of one allele of the elav family RNA binding protein 9 (Rbp9) gene. These su(Hw) null oocytes can be fertilized, with evidence that embryos lacking Su(Hw) show compromised development. Our studies extend the known transcriptional activities of Su(Hw), indicating that Su(Hw) can function as an insulator, activator and repressor, the latter function being essential for oogenesis. These findings highlight that insulator proteins are versatile transcriptional regulatory proteins, suggesting that tissue specific contributions to transcription result from direct regulation of individual genes.
Publication Title
The insulator protein Suppressor of Hairy-wing is an essential transcriptional repressor in the Drosophila ovary.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 12 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Suppressor of Hairy-wing [Su(Hw)] is a multi-zinc finger DNA binding factor required for gypsy insulator function and female germline development in Drosophila. The enhancer-blocking and barrier functions of the gypsy retrotransposon involve Su(Hw) binding to twelve clustered Su(Hw) binding sites (SBSs) and recruitment of the Centrosomal Protein of 190 kD (CP190) and Modifier of mdg4 67.2 kD isoform (Mod67.2) insulator proteins. In contrast, the Su(Hw) germline function involves binding to non-clustered genomic SBSs and does not require CP190 or Mod67.2. Here, we use genome-wide expression analyses in the ovary to identify the first Su(Hw) regulated target genes.
Publication Title
The insulator protein Suppressor of Hairy-wing is an essential transcriptional repressor in the Drosophila ovary.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 9 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The objective of this study was to understand the genetic mechanisms of Vitamin-A-Deficiency (VAD)-induced arrest of spermatogonial stem-cell differentiation. Vitamin A and its derivatives (the retinoids) participate in many physiological processes including vision, cellular differentiation and reproduction. VAD affects spermatogenesis, the subject of our present study. Spermatogenesis is a highly regulated process of differentiation and complex morphologic alterations that, in the postnatal testis, leads to the formation of sperm in the seminiferous epithelium. VAD causes early cessation of spermatogenesis, characterized by degeneration of meiotic germ cells, leading to seminiferous tubules containing mostly type A spermatogonia and Sertoli cells. In this study, we investigated the molecular basis of VAD on spermatogenesis in mice. We used adult Balb/C mice fed with a Control or VAD diet for an extended period of time (8-28 weeks) and selected two time points (18 and 25 weeks) for microarray analysis.
Publication Title
Long-term vitamin A deficiency induces alteration of adult mouse spermatogenesis and spermatogonial differentiation: direct effect on spermatogonial gene expression and indirect effects via somatic cells.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 59 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Autism spectrum disorder (ASD) is an early onset neurodevelopmental disorder, which is characterized by disturbances of brain function and behavioral deficits in core areas of impaired reciprocal socialization, impairment in communication skills, and repetitive or restrictive interests and behaviors. ASD is known to have a significant genetic risk, but the underlying genetic variation can be attributed to hundreds of genes. The molecular and pathophysiologic basis of ASD remains elusive because of its genetic heterogeneity and complexity, its high comorbidity with other diseases, and the paucity of brain tissue for study. The invasive nature of collecting primary neuronal tissue from patients might be circumvented through reprogramming peripheral cells to induced pluripotent stem cells (iPSCs), which are able to generate live neurons carrying the genetic variants of disease. This breakthrough allows us to access the cellular and molecular phenotypes of patients with intrinsic autism, that is patients without known genetic disorders or identifiable syndromes or malformations. To do this, we studied a relatively homogeneous patient population of boys with intrinsic autism by excluding patients with known genetic disease or recognizable phenotypes or syndromes, as well as those with profound mental retardation or primary seizure disorders. We generated iPSCs from patients with intrinsic autism, their unaffected male siblings and age-, and sex-matched unaffected controls. And these stem cells were subsequently differentiated into electrophysiologically active neurons. The expression profile for autistic and their unaffected siblings' iPSC-derived neurons were compared. A distinct expression profile was found between autism and sib control. The significantly differentially expressed genes (> 2-fold, FDR < 0.05) in autistic iPSC-derived neurons were significantly enriched for processes related to synaptic transmission, such as neuroactive ligand-receptor signaling and extracellular matrix interactions (FDR < 0.05), and were significantly enriched for genes previously associated with ASD (p < 0.05). Our findings suggest approaches such as iPSC-derived neurons will be an important method to obtain tissue for study that appropriately recapitulates the complex dynamics of an autistic neural cell.
Publication Title
Idiopathic Autism: Cellular and Molecular Phenotypes in Pluripotent Stem Cell-Derived Neurons.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 8 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Expression profiling of mouse ing2 -/- testis vs WT reveals gene expression differences consistent with spermatogenic arrest and infertility. Ing2 is indispensable for male germ cell development in mice. While mice deficient for Ing2 were born and grew without apparent abnormalities, male, but not female, were infertile, consistent with the highest expression of Ing2 in testes in wild-type mice and in humans. Histological and DNA content analyses in Ing2-/- testes revealed a spermatogenesis arrest at meiotic phase and enhanced apoptosis associated with increased p53, resulting in a decline in mature spermatozoa, which became more severe in older age. HDAC1 accumulation and core histone deacetylation at pachytene stage were impaired in Ing2-/- testes, suggesting that the recruitment of HDAC1 by Ing2 plays a critical role in spermatogenesis. This study establishes Ing2 as a novel mammalian regulator of spermatocyte differentiation, which coordinates spermatogenesis stage-specific histone modifications. This study has implications in understanding human male infertility.
Publication Title
Targeted disruption of Ing2 results in defective spermatogenesis and development of soft-tissue sarcomas.
Sample Metadata Fields
Sex, Specimen part
View Samples- Rattus norvegicus
- 18 Downloadable Samples
- Affymetrix Rat Expression 230A Array (rae230a)
Description
During neurogenesis, expression of the basic Helix-Loop-Helix NeuroD6/Nex1/MATH-2 transcription factor parallels neuronal differentiation, while maintaining the differentiated state in the mature nervous system. To further dissect NeuroD6 differentiation properties, we previously generated a NeuroD6-overexpressing stable PC12 cell line, PC12-ND6, which displays a neuronal phenotype characterized by spontaneous neuritogenesis, accelerated NGF-induced differentiation, and increased regenerative capacity. Furthermore, we reported that NeuroD6 promotes long-term neuronal survival upon oxidative stress triggered by serum deprivation. In this study, we identified the NeuroD6-mediated transcriptional regulatory pathways linking neuronal differentiation to survival, by conducting a genome-wide microarray analysis using PC12-ND6 cells and serum deprivation as a stress paradigm. Through a series of filtering steps and a gene-ontology analysis, we found that NeuroD6 promotes distinct but overlapping gene networks, consistent with the differentiation, regeneration, and survival properties of PC12-ND6 cells. Using a gene set enrichment analysis, we provide the first evidence of a compelling link between NeuroD6 and a set of heat shock proteins in the absence of stress, which may be instrumental to confer stress tolerance to PC12-ND6 cells. Immunocytochemistry results showed that HSP27 and HSP70 interact with cytoskeletal elements, consistent with their roles in neuritogenesis and preserving cellular integrity. HSP70 also colocalizes with mitochondria located in the soma, growing neurites and growth cones of PC12-ND6 cells prior to and upon stress stimulus, consistent with its neuroprotective functions. Collectively, our findings support the notion that NeuroD6 links neuronal differentiation to survival via the network of molecular chaperones and endows the cells with increased stress tolerance.
Publication Title
NeuroD6 genomic signature bridging neuronal differentiation to survival via the molecular chaperone network.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 48 Downloadable Samples
- Illumina HumanHT-12 V4.0 expression beadchip
Description
Glucocorticoids (GCs) are steroid hormones widely used as pharmaceutical interventions, which act mainly by regulating gene expression levels. A large fraction of patients (~30%), especially those of African descent, show a weak response to treatment. To interrogate the contribution of variable transcriptional response to inter-ethnic differences, we measured in vitro lymphocyte GC sensitivity (LGS) and transcriptome-wide response to GCs in peripheral blood mononuclear cells (PBMCs) from African-American and European-American healthy donors. We found that transcriptional response after 8hrs treatment was significantly correlated with variation in LGS within and between populations. We found that NFKB1, a gene previously found to predict LGS within populations, was more strongly downregulated in European-Americans on average. NFKB1 could not completely explain population differences, however, and we found an additional 177 genes with population differences in the average log2 fold change (FDR<0.05), most of which also showed a weaker transcriptional response in AfricanAmericans. These results suggest that inter-ethnic differences in GC sensitivity reflect variation in transcriptional response at many genes, including regulators with large effects (e.g. NFKB1) and numerous other genes with smaller effects.
Publication Title
Inter-ethnic differences in lymphocyte sensitivity to glucocorticoids reflect variation in transcriptional response.
Sample Metadata Fields
Sex, Age, Specimen part, Treatment
View Samples- Homo sapiens
- 72 Downloadable Samples
- Illumina HumanHT-12 V4.0 expression beadchip
Description
Glucocorticoids (GC) and 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3) are steroid hormones with anti-inflammatory properties with enhanced effects when combined. We previously showed that transcriptional response to GCs was correlated with inter-individual and inter-ethnic cellular response. Here, we profiled cellular and transcriptional responses to 1,25(OH)2 D3 from the same donors. We studied cellular response to combined treatment with GCs and 1,25(OH)2 D3 in a subset of individuals least responsive to GCs. We found that combination treatment had significantly greater inhibition of proliferation than with either steroid hormone alone. Overlapping differentially expressed (DE) genes between the two hormones were enriched for adaptive and innate immune processes. Non-overlapping differentially expressed genes with 1,25(OH)2 D3 treatment were enriched for pathways involving the electron transport chain, while with GC treatment, non-overlapping genes were enriched for RNA-related processes. These results suggest that 1,25(OH)2 D3 enhances GC anti-inflammatory properties through a number of shared and non-shared transcriptionally-mediated pathways.
Publication Title
Comparison of cellular and transcriptional responses to 1,25-dihydroxyvitamin d3 and glucocorticoids in peripheral blood mononuclear cells.
Sample Metadata Fields
Sex, Age, Specimen part, Treatment
View Samples- Mus musculus
- 46 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
ZnO nanoparticles can elicit a range of perturbed cell responses in vitro. Exposure to topically applied sunscreens containing ZnO particles may or may not elicit a biological effect in mice.
Publication Title
Dermal absorption and short-term biological impact in hairless mice from sunscreens containing zinc oxide nano- or larger particles.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus, Homo sapiens
- 9 Downloadable Samples
Affymetrix Human Genome U133A 2.0 Array (hgu133a2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Identical gene regulation patterns of T3 and selective thyroid hormone receptor modulator GC-1.
Sample Metadata Fields
Sex, Age, Specimen part, Cell line
View Samples