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SRP065341
Caenorhabditis elegans
46 Downloadable Samples
Illumina HiSeq 2000
Description
Environmental stress-induced transgenerational epigenetic effects have been observed in various model organisms and human. The capacity and mechanism of such phenomena, particularly in animals, are poorly understood. In C. elegans, siRNA mediates transgenerational gene silencing through the germline nuclear RNAi pathway. At the organismal level, this pathway plays a transgenerational role in maintaining the germline immortality when C. elegans is under a mild heat stress. However, the underlying molecular mechanism is unknown. In this study, we performed a 12-generation temperature-shift experiment (15°C->23°C->15°C) using the wild type (N2) and a mutant strain that lacks the germline-specific nuclear AGO protein HRDE-1/WAGO-9. We found that the temperature-sensitive mortal germline (Mrt) phenotype of the hrde-1 mutant is reversible, indicating a transgenerational cumulative but also reversible nature of the underlying molecular cause. By taking the whole-genome RNA and chromatin profiling approaches, we revealed an epigenetic role of HRDE-1 in repressing heat stress-induced transcriptional activation of over 280 genes, predominantly in or near LTR retrotransposons. Strikingly, for some of these elements, the heat stress-induced transcription becomes progressively activated in the hrde-1 mutant over several generations under heat stress. Furthermore, the effect of heat stress-induced transcription activation is heritable for at least two generations after the heat stress. Interestingly, the siRNA expression of these genes tend to be heat-inducible in the wild type animals, but not in the hrde-1 mutant, suggesting a role of siRNAs in repressing heat-inducible elements. Our study revealed a novel phenomenon of transgenerational feed-forward transcriptional activation, which is normally repressed in the wild type C. elegans by the germline nuclear RNAi pathway. It also provides a new paradigm to study epigenetic circuitry that connects the environment and gene regulation in the germline. Overall design: In this study, we performed a 12-generation temperature-shift experiment (15°C->23°C->15°C) using the wild type and hrde-1 mutant. mRNA-seq, Pol II ChIP-seq, H3K9me3 ChIP-seq, and small RNA-seq analyses were performed for all or some of the generations. The effects of temperature change in whole-genome mRNA expression, siRNA expression, gene transcription, and H3K9me3 were investigated at the multigenerational time scale in both the WT and hrde-1 mutant animals.
Publication Title
A transgenerational role of the germline nuclear RNAi pathway in repressing heat stress-induced transcriptional activation in C. elegans.
Sample Metadata Fields
Subject
View Samples- Homo sapiens
- 13 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Comparison of human iPSC lines, ESC and fibroblasts to determine their expression patterns. All early passage female lines profiled expressed XIST RNA which is an indicator of an inactive X chromosome. Genes on the X-chromosome were also analyzed for overall levels of gene expression compared to human fibroblasts.
Publication Title
Female human iPSCs retain an inactive X chromosome.
Sample Metadata Fields
Specimen part
View Samples- Oryza sativa indica group
- 14 Downloadable Samples
- Affymetrix Rice Genome Array (rice)
Description
Detailed analysis of genome-wide transcriptome profiling in rice root is reported here, following Cr-plant interaction. Such studies are important for the identification of genes responsible for tolerance, accumulation and defense response in plants with respect to Cr stress. Rice root metabolome analysis was also carried out to relate differential transcriptome data to biological processes affected by Cr (VI) stress in rice.
Publication Title
Transcriptomic and metabolomic shifts in rice roots in response to Cr (VI) stress.
Sample Metadata Fields
Age, Specimen part, Treatment
View Samples- Oryza sativa indica group
- 18 Downloadable Samples
- Affymetrix Rice Genome Array (rice)
Description
Traditional rice varieties found in India have many desirable characteristics. Amongst them, their differential responses to abiotic and biotic stresses are of great agricultural importance. Drought or osmotic stress is one of the major abiotic stresses afflicting crop plants in India. Indigenous varieties like Dagad deshi have been found to be drought resistant and, thereby, are being studied in great detail by plant breeders and biotechnologists alike. In this study, we have analyzed the transciptomes of two contrasting cultivars, i.e. Dagad deshi (tolerant) and IR20 (susceptible), under control and stress conditions to elucidate the differences in their responses to drought stress using Affymetrix microarray platform.
Publication Title
Reference genes for accurate gene expression analyses across different tissues, developmental stages and genotypes in rice for drought tolerance.
Sample Metadata Fields
Specimen part, Time
View Samples- Homo sapiens
- 2 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Gene expression profiles were performed to compare the difference in sigmoid colon biopsies between from healthy control and patients with ulcerative colitis.
Publication Title
MicroRNAs are differentially expressed in ulcerative colitis and alter expression of macrophage inflammatory peptide-2 alpha.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 22 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
A gene expression signature characterizes expression data from breast cancer samples of patients with pathological complete response (pCR) or residual disease (RD) following the neoadjuvant trial.
Publication Title
A gene expression signature that predicts the therapeutic response of the basal-like breast cancer to neoadjuvant chemotherapy.
Sample Metadata Fields
Sex, Disease stage, Race
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Exon 1.0 ST Array [probe set (exon) version (huex10st)
Description
We are investigating the transcriptional response of changes in RNA steady-state levels between normal and DM1.
Publication Title
RNA steady-state defects in myotonic dystrophy are linked to nuclear exclusion of SHARP.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 13 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Profiling project of a panel of tubular adenoma and serrated adenoma patient material collected in the Academic Medical Center (AMC) in Amsterdam, The Netherlands. The aim of the study was to compare the expression profiles of different types of colon cancer precursor lesions (tubular versus serrated adenomas) and determine their correspondence with a set of colon cancer patient-derived profiles that have distinct clinical outcomes.
Publication Title
Poor-prognosis colon cancer is defined by a molecularly distinct subtype and develops from serrated precursor lesions.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 31 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Inflammation has pleiotropic effects on carcinogenesis and tumor progression. Signaling through the adaptor protein MyD88 promotes carcinogenesis in several chemically induced cancer models. Interestingly, we observed a protective role for MyD88 in the development of AOM/DSS colitis-associated cancer. The inability of Myd88-/- mice to heal ulcers generated upon injury creates an inflammatory environment that increases the frequency of mutations and results in a dramatic increase in adenoma formation and cancer progression. Susceptibility to colitis development and enhanced polyp formation were also observed in Il18-/- mice upon AOM/DSS treatment, suggesting that the phenotype of MyD88 knockouts is in part due to their inability to signal through the IL-18 receptor. This study revealed a previously unknown level of complexity surrounding MyD88 activities downstream of different receptors that differentially impact tissue homeostasis and carcinogenesis.
Publication Title
MyD88-mediated signaling prevents development of adenocarcinomas of the colon: role of interleukin 18.
Sample Metadata Fields
Specimen part, Disease, Disease stage
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Myeloid-derived cells comprising the tumor stroma represent a heterogeneous population of cells critical to the structure, function and growth of established cancers. We have recently found that engineering tumor-specific CD8+ T cells to secrete IL-12 (IL-12TD) can lead to striking improvements in T-cell activity against established melanomas in murine models. Surprisingly, IL-12-dependent enhancement of CD8+ T-cell anti-tumor function did not occur through direct ligation of receptors on lymphocytes or NK cells. Instead, IL-12 sensitized host bone marrow-derived tumor-stromal cells, partly through interferon-gamma, to indirectly enhance the effects of adoptively-transferred T cells. Direct presentation of antigen by tumor was not necessary, but MHC class I expression on endogenous cells was essential for IL-12 mediated anti-tumor enhancements. Upon successful treatment with IL-12TD cells, we observed the selective elimination of tumor-infiltrating CD11b+ F4/80+ macrophages, CD11b+/ClassII+/CD11c+ dendritic cells and CD11b+/Ly6C+/Ly6G- but not CD11b+/Ly6C+/Ly6G+ myeloid-derived suppressor cells within regressing lesions. These results are consistent with a model whereby IL-12 triggers the maturation of myeloid-derived cells into competent antigen cross-presenting cells. Licensed recognition of these antigens by effector T cells may in turn trigger the collapse of the tumor stroma and aid in the regression of large vascularized lesions.
Publication Title
IL-12 triggers a programmatic change in dysfunctional myeloid-derived cells within mouse tumors.
Sample Metadata Fields
Specimen part, Disease, Disease stage
View Samples